TWI600702B - Sheet-like epoxy resin composition for face sealing organic el component, method of manufacturing organic el device using the same,organic el device, organic el display panel and organic el lighting - Google Patents

Description

Sheet-like epoxy resin composition for surface sealing of organic EL element, method for producing organic EL device using the same, organic EL device, organic EL display panel, and organic EL illumination

The present invention relates to a sheet-like epoxy resin composition, a method for producing an organic electroluminescence (EL) device using the same, an organic EL device, and an organic EL display panel.

Among optical devices, optical semiconductors, particularly organic EL elements, are expected to be applied to illumination devices or next-generation displays because of their excellent low power consumption, high viewing angle, and polarization characteristics. However, an optical semiconductor typified by an organic EL element has a problem of being easily deteriorated by moisture or oxygen in the atmosphere. Therefore, the organic EL element is used by sealing with a sealing member, and a sealing material for producing a sealing member having a lower moisture permeability is highly desired.

As a sealing material for an optical element or an electronic component, a composition including an epoxy resin containing a fluorene skeleton, a curing agent, a curing accelerator, a coupling agent, and the like is proposed (for example) For example, refer to Patent Document 1). The cured product of the composition containing the epoxy resin of the first skeleton has high moisture resistance, and can effectively suppress deterioration of the organic EL element. However, when the element is sealed, the composition needs to be heated and melted, and further injection molding is performed. Therefore, there is a problem that the sealing step is complicated.

On the other hand, a sheet-like sealing composition containing a low molecular weight epoxy resin, a high molecular weight epoxy resin, a latent imidazole compound, and a decane coupling agent is also proposed (for example, refer to Patent Document 2 and Patent Document 3). The sheet-like sealing composition is thermocompression-bonded to the element and transferred, and the element can be sealed (face-sealed) only by heat-hardening the epoxy resin.

However, as a sealant of a photo sensor or a light-emitting diode (LED), a compound containing Zn(C _n H _2n+1 COO) ₂ and an imidazole compound are proposed. An epoxy resin composition as a curing accelerator (for example, Patent Document 4). In addition, as a powder coating material, a composition including a metal complex in which an amine compound and a carboxylate are respectively disposed on a metal ion such as zinc is proposed (for example, Patent Document 5). Further, as a curing accelerator for an epoxy resin, a specific metal complex is proposed (for example, Non-Patent Document 1).

Prior art literature

Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2005-41925

Patent Document 2: Japanese Patent Laid-Open Publication No. 2006-179318

Patent Document 3: Japanese Patent Laid-Open Publication No. 2007-112956

Patent Document 4: Japanese Patent Laid-Open No. Hei 10-45879

Patent Document 5: International Publication No. 2006/022899

Non-patent literature

Non-Patent Document 1: International Polymer (Polymer International), Vol. 58, No. 9, 2009, 976-988

However, the conventional sheet-like sealing composition described in Patent Document 2, Patent Document 3, and the like contains a component having a relatively high molecular weight in many cases in order to maintain a sheet shape. Therefore, when the epoxy resin is cured while the sheet-like sealing composition is being stored, the molecular weight of the epoxy resin contained in the composition is rapidly increased. When the molecular weight of the epoxy resin is too large, the flexibility of the sheet-like sealing composition is lowered. Therefore, when the sheet-like sealing composition is used to seal an optical semiconductor such as an organic EL element, the semiconductor may not be sufficiently covered. The case where the sealing becomes insufficient.

Further, the composition of Patent Document 4 may have insufficient curability. The composition of Patent Document 5 can be relatively improved in storage stability, but has high viscosity, and therefore it is considered to be unsuitable as a sealant. Non-Patent Document 1 merely indicates that a specific metal complex is combined with a low molecular weight epoxy resin, and does not mean a combination with a high molecular weight epoxy resin.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a sheet-like epoxy resin composition which has high storage stability and maintains sufficient curability.

The present inventors have found that by combining an epoxy resin having a relatively high molecular weight for maintaining a sheet shape and a metal complex having a specific structure, it can be solved. The subject.

[1] A sheet-like epoxy resin composition comprising: an epoxy resin (A) having two or more epoxy groups in one molecule, and having a weight average molecular weight of from 2 × 10 ³ to 1 × 10 ⁵ ; And a metal complex (B) containing at least one metal ion selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr, and capable of forming a complex with the metal ion and not A tertiary amine having an NH bond and an anionic ligand having a molecular weight of 17 to 200.

[2] The sheet-like epoxy resin composition according to the above [1], wherein a valence of the anionic ligand is less than a valence of the metal ion, and a radius of the anionic ligand is 2.0 Å or more .

[3] The sheet-like epoxy resin composition according to the above [1] or [2] wherein the tertiary amine is a compound represented by any one of the following formulas (1) to (6) :

(In the formula (1), R ₁ represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and R ₂ , R ₃ and R ₄ each independently represent a hydrogen group, An aliphatic hydrocarbon group having 1 to 17 carbon atoms, a hydroxyl group, an aryl group-containing group or a cyanoethyl group)

(In the formula (2), RB1, RB3, RB4, and RB5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group, or a cyanoethyl group. ; RB2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and a plurality of groups selected from the group consisting of RB1, RB2, RB3, RB4, and RB5 may mutually Linking to form an alicyclic ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from oxygen, nitrogen, and sulfur)

[Chemical 3]

(In the formula (3), RC1, RC3, RC4 and RC5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. ; RC2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and a plurality of groups selected from RC1, RC2, RC3, RC4, and RC5 may mutually Linking to form an alicyclic ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from oxygen, nitrogen, and sulfur)

(In the general formula (4), RE1, RE2, RE3, RE4, and RE5 each independently represent a hydrogen group and have a carbon number of 1 ~17 may contain a hetero atom-containing aliphatic hydrocarbon group, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; a plurality of groups selected from the group consisting of RE1, RE2, RE3, RE4, and RE5 may be bonded to each other to form an alicyclic group. a ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from the group consisting of oxygen, nitrogen, and sulfur)

(In the formula (5), RF1, RF2, RF3, RF4, RF5, RF6, and RF7 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 and a hetero atom, a hydroxyl group, and an aryl group-containing group. a group or a cyanoethyl group; a plurality of groups selected from the group consisting of RF1, RF2, RF3, RF4, RF5, RF6, and RF7 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a compound selected from the group consisting of oxygen, nitrogen, and sulfur. Heteroatom of hetero atom)

[Chemical 6]

(In the formula (6), RG1, RG2, RG3, and RG4 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. A plurality of groups selected from the group consisting of RG1, RG2, RG3, and RG4 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

[4] The sheet-like epoxy resin composition according to any one of [1] to [3] wherein the anionic ligand is a group having two or more selected from the group consisting of O, S, and P. The group may be bonded to the atom of the above metal ion, and may be located in the above metal ion to form a 3 to 7 member ring.

[5] The sheet-like epoxy resin composition according to the above [3], wherein the tertiary amine is a compound represented by any one of the formula (1) to the formula (3), and the anionic property The ligand is an anion of a carboxylate compound represented by the following formula (7A) or a carboxylate compound represented by the following formula (7B): [Chem. 7]

(In the formula (7A), RD1 is a hydrogen group, and RD2 is a hydrogen group or a hydrocarbon group having 1 to 10 carbon atoms or a hydroxyl group)

(In the formula (7B), RD2 is a hydrogen group or a hydrocarbon group having 1 to 10 carbon atoms or a hydroxyl group).

[6] The sheet-like epoxy resin composition according to any one of the above [1] to [5] wherein the above-mentioned sheet-like epoxy resin composition is in CDCl ₃ at 25 ° C, 270 MH chemical shifts in the ¹ H NMR chemical shift derived from a tertiary amine, in CDCl ₃ alone is moved above the peak at 0.05ppm 25 ℃, the chemical shift of ¹ H NMR at 270MHz with respect to the tertiary amine.

[7] The sheet-like epoxy resin composition according to any one of the above [1] to [6] wherein The molar ratio of the above tertiary amine to the above metal ion is from 0.5 to 6.0.

[8] The sheet-like epoxy resin composition according to the above [5], wherein the above carboxylate compound is selected from the group consisting of 2-ethylhexanoic acid, formic acid, acetic acid, butyric acid, 2-ethylbutyric acid, 2 At least one compound of a group consisting of 2-dimethylbutyric acid, 3-methylbutyric acid, 2,2-dimethylpropionic acid, benzoic acid, and naphthenic acid.

[9] The sheet-like epoxy resin composition according to any one of [1] to [8] wherein the tertiary amine is selected from 1,8-diazabicyclo[5,4,0] Undec-7-ene, 1-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-isobutyl-2-methylimidazole, 1-butyl At least one compound of the group consisting of imidazole and 1,5-diazabicyclo[4,3,0]non-5-ene.

[10] The sheet-like epoxy resin composition according to any one of the above [1] to [9] wherein the above-mentioned sheet-like epoxy resin composition has an equivalent functional group/epoxy group equivalent of a tertiary amine The above metal complex (B) is contained in a range of from 0.008 to 0.3.

[11] The sheet-like epoxy resin composition according to any one of [1] to [10] wherein the content of the epoxy resin (A) is 55 with respect to the sheet-like epoxy resin composition. Mass %~95% by mass.

[12] A sheet for sealing, comprising a layer comprising the sheet-like epoxy resin composition according to any one of the above [1] to [11].

[13] The sheet for sealing according to the above [12], wherein the layer containing the sheet-like epoxy resin composition has a light transmittance of 90% or more at a thickness of 40 μm and a wavelength of 550 nm.

[14] The sheet for sealing according to the above [12] or [13], wherein the sheet is contained therein At least one surface of the layer of the epoxy resin composition further has a protective film.

[15] The sheet for sealing according to any one of [12] to [14] which is used for surface sealing of an optical semiconductor.

[16] The sheet for sealing according to any one of [12] to [14] which is used for surface sealing of an organic EL element.

[17] The sheet for sealing according to any one of the above [12] to [14] wherein the layer containing the sheet-like epoxy resin composition has a water content of 0.1% by mass or less.

[18] A method of producing an organic EL device, comprising: a step of preparing a substrate on which an organic EL device is formed; and the sheet-like epoxy resin composition according to any one of the above [1] to [11] a step of covering the organic EL element; and a step of sealing the organic EL element by a cured product of the layer containing the sheet-like epoxy resin composition.

[19] An organic EL device comprising: an organic EL device; and a cured layer of the sheet-like epoxy resin composition according to any one of the above [1] to [11], which is the same as the above organic EL device Contact and the surface sealing of the above organic EL element.

[20] An organic EL device comprising: an organic EL device; and a cured layer of a sheet-like epoxy resin composition, wherein the cured layer of the sheet-like epoxy resin composition is surface-sealed by the organic EL device In the spectrum measured by X-ray photoelectric spectrophotometry (XPS), one or more kinds selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr are detected. a peak of a metal atom and a peak derived from a nitrogen atom, and the detected molar ratio of the above metal atom to the nitrogen atom is the above metal atom: the above nitrogen atom =1: 0.5 to 1:6.0, and the content of the above metal atom is from 0.5% by mass to 15% by mass.

[21] An organic EL display panel comprising the organic EL device according to [19] above.

[22] An organic EL illumination having the organic EL device according to [19] above.

The sheet-like epoxy resin composition of the present invention is excellent in hardenability and storage stability. Therefore, even after the composition is held for a predetermined period of time, the sealing conditions of the optical semiconductor such as the organic EL element can be made constant to some extent, and the manufacturing efficiency of the optical semiconductor can be improved. Further, since the cured product of the sheet-like epoxy resin composition of the present invention has high transparency, it can also be applied to an apparatus comprising a light-emitting transmission sealing layer of an organic EL element.

10, 10'‧‧‧Seal film

12‧‧‧Base film

14‧‧‧ gas barrier

16‧‧‧layer containing a sheet of epoxy resin composition

18‧‧‧Protective film

20‧‧‧Organic EL device

22‧‧‧Display substrate

24‧‧‧Organic EL components

26‧‧‧ facing substrate (transparent substrate)

28‧‧‧ Sealing members

30‧‧‧Cathode reflective electrode layer

32‧‧‧Organic EL layer

34‧‧‧Anode transparent electrode layer

Fig. 1 is a cross-sectional view showing an example of a sheet-like epoxy resin composition of the present invention.

Fig. 2 is a cross-sectional view showing an example of a sheet-like epoxy resin composition of the present invention.

3 is a cross-sectional view showing an example of an organic EL device of the present invention.

1. Sheet epoxy resin composition

The sheet-like epoxy resin composition of the present invention contains at least a high molecular weight epoxy resin (A) and a metal complex (B). The sheet-like epoxy resin composition may further contain, as needed, a low molecular weight epoxy resin (C), a decane coupling agent (D) having an epoxy group or a functional group reactive with an epoxy group, a solvent (E), And at least one of the other ingredients More than one species.

The sheet-like epoxy resin composition of the present invention is preferably thermosetting. The thermosetting hardening accelerator is less likely to decompose at the time of curing than the photocurable hardening accelerator. Further, it is difficult for the decomposition product of the thermosetting hardening accelerator to deteriorate the optical element, and it is also difficult to impair the transparency of the cured product of the composition. The metal complex (B) which functions as a hardening accelerator in the present invention not only has these characteristics, but also is stable at room temperature, so that it does not undergo a hardening reaction during storage, but is intended to be reacted. The hardening reaction is easy at the temperature. Therefore, the sheet-like epoxy resin composition of the present invention, although containing a high molecular weight epoxy resin (A), inhibits the hardening reaction at the time of storage of the epoxy resin, and exhibits good storage stability, and when used. Shows sufficient hardenability.

The sheet-like epoxy resin composition of the present invention can be used as a sheet for sealing (sheet for face sealing), a sheet for transparent coating, a sheet for transparent filling, etc., and is preferably used as a sheet for sealing (sheet for surface sealing) ). Hereinafter, an example in which the sheet-like epoxy resin composition of the present invention is used as a sheet for sealing (sheet for surface sealing) will be described. In addition, the transparent filler is, for example, a material that requires transparency between a substrate such as a touch panel and an image display device such as a liquid crystal panel.

<High molecular weight epoxy resin (A)>

The high molecular weight epoxy resin (A) contained in the sheet-like epoxy resin composition of the present invention is an epoxy resin having two or more epoxy groups in one molecule, and may have a molecular weight distribution or may have no molecular weight distribution. . The high molecular weight epoxy resin (A) in the present invention is an epoxy resin having a weight average molecular weight of 2 × 10 ³ to 1 × 10 ⁵ , preferably a weight average molecular weight of 3 × 10 ³ to 8 × 10 ⁴ , more It is preferably 4×10 ³ ~ 6×10 ⁴ epoxy resin.

The above weight average molecular weight can be measured by gel permeation chromatography (GPC) using polystyrene as a standard substance under the following conditions.

Device: SHODEX manufacturing, GPC-101

Developing solvent: tetrahydrofuran

Standard polystyrene: PS-1 (molecular weight 580~7,500,000) manufactured by VARIAN, PS-2 manufactured by Varian (molecular weight 580~377,400)

The epoxy equivalent of the high molecular weight epoxy resin (A) is preferably from 500 g/eq to 1 × 10 ⁴ g in terms of a viewpoint that the crosslinking density of the cured product of the sheet-like epoxy resin composition is constant or more. /eq, more preferably 600g/eq~9000g/eq.

The high molecular weight epoxy resin (A) is preferably a resin containing a bisphenol skeleton in the main chain from the viewpoint of lowering the moisture permeability of the cured product of the sheet-like epoxy resin composition. The high molecular weight epoxy resin (A) is particularly preferably a resin containing bisphenol and epichlorohydrin as a monomer component, and particularly preferably an oligomer having bisphenol and epichlorohydrin as a monomer component.

All of the monomer components constituting the high molecular weight epoxy resin (A) may be bisphenol and epichlorohydrin; and a part of the monomer components constituting the epoxy resin may be components other than bisphenol or epichlorohydrin (total Monomer component). Examples of the comonomer component include: a dihydric or higher polyhydric alcohol (e.g., a binary phenol or a diol, etc.). When a part of the monomer component is a component other than bisphenol or epichlorohydrin (co-monomer component), the molecular weight tends to be in a desired range.

Preferable examples of the high molecular weight epoxy resin (A) include a resin having a repeating structural unit represented by the following formula (11).

In the above formula (11), X represents a single bond, a methylene group, an isopropylidene group, -S- or -SO ₂ -. The structural unit in which X of the formula (11) is a methylene group is a bisphenol F type structural unit; and the structural unit in which X is an isopropylidene group is a bisphenol A type structural unit.

In the above formula (11), R ₁ each independently represents an alkyl group having 1 to 5 carbon atoms, preferably a methyl group. P is a substitution number of the substituent R ₁ and is an integer of 0 to 4. From the viewpoint of heat resistance or low moisture permeability, P is preferably 0.

In the above formula (11), n is a repeating number of the structural unit represented by the formula (11), and is an integer of 2 or more.

The oligomer of the high molecular weight epoxy resin (A) may include a "bisphenol F type repeating structural unit" in which X in the above formula (11) is a methylene group, and the above formula (11) X is a bisphenol A type repeating structural unit of isopropylidene. If the oligomer contains a bisphenol A type repeating structural unit, the viscosity of the sheet-like epoxy resin composition is easily improved. On the other hand, if the oligomer contains a bisphenol F-type repeating structural unit, the steric hindrance of the oligomer tends to be small. Therefore, multiple phenyl groups are easily aligned, On the other hand, the moisture permeability of the cured product of the sheet-like epoxy resin composition is liable to lower.

The number (F) of "bisphenol F type repeating structural unit" contained in one molecule is relative to the number (A) of "bisphenol A type repeating structural unit" contained in one molecule of the above oligomer The ratio of the total number (F) of the "bisphenol F type repeating structural unit": {(F / (A + F)) × 100} is preferably 50% or more, more preferably 55% or more. When a large amount of "bisphenol F type repeating structural unit" is contained, the moisture permeability of the cured product of the sheet-like epoxy resin composition is sufficiently lowered.

The content of the high molecular weight epoxy resin (A) is preferably 100% based on 100 parts by mass of the total of the metal complex (B), the low molecular weight epoxy resin (C), and the decane coupling agent (D) described below. The mass parts are -2000 parts by mass, more preferably 210 parts by mass to 2000 parts by mass, and particularly preferably from 250 parts by mass to 1200 parts by mass. When the content ratio of the high molecular weight epoxy resin (A) is not more than a certain value, the fluidity of the sheet-like epoxy resin composition is hardly impaired when it is pressure-bonded to a member to be sealed such as a photo-semiconductor, and it is easy to seal. In addition, when the content ratio of the high molecular weight epoxy resin (A) is at least a certain value, the shape retainability of the sheet-like epoxy resin composition or the moisture resistance of the cured product is also likely to be good.

The content of the high molecular weight epoxy resin (A) in the sheet-like epoxy resin composition containing the low molecular weight epoxy resin (C) described later is 100 parts by mass of the low molecular weight epoxy resin (C). Preferably, it is 100 parts by mass to 1500 parts by mass, more preferably 120 parts by mass to 1200 parts by mass, and particularly preferably 150 parts by mass to 1000 parts by mass. When the content ratio of the high molecular weight epoxy resin (A) is 1,500 parts by mass or less, the composition of the sheet-like epoxy resin composition is thermocompression bonded to the material to be sealed. The liquidity is easy to improve. On the other hand, when the content ratio of the high molecular weight epoxy resin (A) is 100 parts by mass or more, the shape stability of the sheet-like epoxy resin composition is likely to be improved. Further, there is a tendency that the moisture permeability of the cured product is also lowered.

The content of the high molecular weight epoxy resin (A) is preferably from 55% by mass to 95% by mass, and more preferably from 55% by mass to 92% by mass based on the total amount of the sheet-like epoxy resin composition.

The high molecular weight epoxy resin (A) may be used alone or in combination of two or more. For example, a high molecular weight epoxy resin (A-1) having a weight average molecular weight of 1 × 10 ⁴ or less and a high molecular weight epoxy resin (A-2) having a weight average molecular weight of more than 1 × 10 ⁴ can be combined. The mass ratio of the epoxy resin (A-1) to the epoxy resin (A-2) can be set to (A-1)/(A-2)=10/90 to 90/10, preferably 10/90~. 40/60.

<Metal Complex (B)>

The metal complex (B) contained in the sheet-like epoxy resin composition of the present invention functions as a curing accelerator for an epoxy resin.

The metal ion in the metal complex (B) may be a metal ion selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr. From the viewpoint of improving the transparency of the cured product of the sheet-like epoxy resin composition, Zn is preferable. Further, when the metal complex (B) contains two or more kinds of metal ions, at least one of the metal ions may be a metal ion selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr.

In order to reduce the reactivity of the tertiary amine under storage conditions, the tertiary amine in the metal complex (B) preferably forms a complex with the metal ion and does not have an N-H bond. Further, the tertiary amine in the metal complex (B) preferably has a molecular weight of 65 to 300. The reason is that if the molecular weight of the tertiary amine is too large, the solubility of the metal complex (B) in the sheet-like epoxy resin composition may be lowered or the catalytic activity may be lowered.

The tertiary amine in the metal complex (B) is preferably a compound represented by any one of the following formulas (1) to (6). It is considered that these compounds concentrate on the conjugated electron cloud on the nitrogen atom constituting the ring, and it is easy to form a complex compound with the metal ion stably. Further, the cured layer of the sheet-like epoxy resin composition containing these compounds has a small decrease in transparency and a haze increase even when subjected to plasma treatment, and has good plasma resistance or weather resistance. Propensity.

The metal complex (B) is stabilized by forming a tertiary amine which is highly reactive and causes a cured product of the resin composition to form a complex, and thus it is difficult to color the sheet-like epoxy resin composition or the cured product thereof. . Therefore, the sheet-like epoxy resin composition of the present invention can be preferably used for the purpose of requiring transparency to a cured product, such as a face sealing material of a top emission type organic EL element.

[化10]

In the formula (1), R ₂ , R ₃ and R ₄ each independently represent a hydrogen group, an aliphatic hydrocarbon group having 1 to 17 carbon atoms, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the group containing an aryl group include an aryl group such as a phenyl group or a naphthyl group; and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11.

R ₁ is a substituent other than a hydrogen atom (aliphatic hydrocarbon group, aryl group, hydroxyl group or cyanoethyl group). The reason is that when R ₁ is a hydrogen atom, the sealing layer containing the cured product of the sheet-like epoxy resin composition is reduced in transparency due to exposure to plasma or the like, as compared with the case where R ₁ is another substituent. Happening.

Specific examples of the amine compound represented by the formula (1) include the following 1-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, and 1-isobutyl-2. -methylimidazole, 1-butylimidazole, 1-benzyl-2-phenylimidazole, 2-phenyl-4-methylimidazole, and the like.

In the general formula (2), RB1, RB3, RB4, and RB5 are each independently represented. A hydrogen group or an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. RB2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. A plurality of groups appropriately selected from RB1, RB2, RB3, RB4, and RB5 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the aryl group-containing group include an aryl group such as a phenyl group, a naphthyl group, and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11. Specific examples of the amine compound represented by the formula (2) include the following 1,8-diazabicyclo[5,4,0]undec-7-ene.

In the formula (3), RC1, RC3, RC4 and RC5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. RC2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. A plurality of groups appropriately selected from RC1, RC2, RC3, RC4, and RC5 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the aryl group-containing group include an aryl group such as a phenyl group, a naphthyl group, and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11.

Specific examples of the amine compound represented by the formula (3) include the following 1,5-diazabicyclo[4,3,0]non-5-ene.

In the formula (4), RE1, RE2, RE3, RE4, and RE5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyano group. base. A plurality of groups selected from the group consisting of RE1, RE2, RE3, RE4, and RE5 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the aryl group-containing group include an aryl group such as a phenyl group, a naphthyl group, and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11.

Specific examples of the amine compound represented by the formula (4) include the compounds represented by the following formula (4-1).

[Chemistry 14]

In the formula (4-1), R represents a hydrogen group, -CH ₃ or -OCH ₃ .

In the formula (5), RF1, RF2, RF3, RF4, RF5, RF6, and RF7 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 and a hetero atom, a hydroxyl group, and an aryl group-containing group. Or cyanoethyl. A plurality of groups selected from the group consisting of RF1, RF2, RF3, RF4, RF5, RF6, and RF7 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the group containing an aryl group include an aryl group such as a phenyl group or a naphthyl group; and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11. Specific examples of the amine compound represented by the formula (5) include the compounds represented by the following formula (5-1).

In the formula (5-1), R independently represents a hydrogen group, -CH ₃ or -OCH ₃ .

In the formula (6), RG1, RG2, RG3, and RG4 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group, or a cyanoethyl group. A plurality of groups selected from the group consisting of RG1, RG2, RG3, and RG4 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur.

The aliphatic hydrocarbon group having 1 to 17 carbon atoms is preferably an alkyl group having 1 to 6 carbon atoms. Examples of the aryl group-containing group include an aryl group such as a phenyl group, a naphthyl group, and an arylalkyl group such as a benzyl group. The constituent carbon group of the aryl group-containing group is preferably in the range of 6 to 11.

Specific examples of the amine compound represented by the formula (6) include the following compounds represented by the following formula (6-1).

In the tertiary amine, for example, the pKa of the compound represented by the formula (4) is about 5, and the compound represented by the formula (1) has a pKa of about 7, and is a compound represented by the formula (2). One of the diazabicycloundecenes has a pKa of about 12. That is, the compound represented by the formula (1) or the formula (2) tends to exhibit high basicity as compared with the compound represented by the formula (4). That is, the alkalinity is high and the ring is In view of the fact that the curing activity of the oxygen resin is good, the tertiary amine in the metal complex (B) is preferably a compound represented by any one of the formulae (1) to (3).

The tertiary amine which forms a complex with the metal ion may be one type or two or more types. That is, the metal complex (B) may be a multinuclear complex compound in which a plurality of metal ions are used as a central metal.

The molar ratio of the tertiary amine to the metal ion in the metal complex (B) is preferably from 0.5 to 6.0, more preferably from 0.6 to 2.0. When the molar ratio is 0.5 or more, the amount of the tertiary amine to be contained in the metal complex (B) is large, and the hardenability of the sheet-like epoxy resin composition tends to be good. On the other hand, when the molar ratio is 6.0 or less, since the tertiary amine which is contained in the metal complex (B) is small, the storage stability of the sheet-like epoxy resin composition is good. When the molar ratio is within the above range, the balance between the hardenability and the storage stability is good.

The anionic ligand in the metal complex (B) is an acidic group having an atom selected from the group consisting of O, S, P, and halogen, and is coordinately bonded or ionically bonded to the metal ion. Compound.

The valence of the anionic ligand is preferably less than the valence of the metal ion. The reason is that an anionic ligand having a valence of less than a metal ion can be bonded to two or more metal ions to stabilize the metal complex (B).

The molecular weight of the anionic ligand is preferably from 17 to 200. When the molecular weight of the anionic ligand is 17 or more, the coordination bond distance between the metal ion and the tertiary amine is likely to be small as described later, and thus the hardening property of the metal complex (B) is hard to be affected. damage. On the other hand, if the molecular weight of the anionic ligand is 200 Hereinafter, the anionic ligand is not excessively large, and therefore does not significantly interfere with the coordination of the tertiary amine with the metal ion due to its steric hindrance. As a result, it is considered that the stability of the metal complex (B) under storage conditions is hard to be impaired.

The radius of the anionic ligand is preferably 2.0 Å or more, more preferably 2.4 Å or more. The reason is that it contributes to the hardening promoting property of the metal complex (B). For example, when two anionic ligands are coordinated to a metal ion, if the tertiary amine is further coordinated to the metal ion, one of the anionic ligands is bonded to the metal ion and the other is anionic. The angle formed by the bond between the seat and the metal ion is reduced and stabilized. It is considered that if the radius of the anionic ligand is 2.0 Å or more, the angle between the bonds is difficult to be reduced, and thus the coordination bonding distance between the metal ion and the tertiary amine tends to be small. As a result, it is considered that the hardening accelerating property of the metal complex (B) is hard to be impaired. When the hardening accelerating property of the metal complex (B) is hard to be damaged, the degree of hardening of the surface of the cured product is likely to be high. When the degree of hardening of the surface of the cured product is high, when a passivation layer or the like is formed on the surface of the cured product, the smoothness of the surface of the cured product is hard to be damaged. Therefore, it is considered that the external haze of the cured product is hard to rise, and the transparency is hard to be damaged.

On the other hand, the upper limit of the radius of the anionic ligand can be set to about 200 Å. It is considered that if the radius of the anionic ligand is 200 Å or less, the size of the anionic ligand does not significantly hinder the coordination of the tertiary amine with the metal ion due to its steric hindrance. As a result, it is considered that the stability of the metal complex (B) under storage conditions is hard to be impaired.

The radius of the anionic ligand can be found in the anionic ligand After the connolly volume, it is calculated as the radius at which the connolly volume is assumed to be the volume of the sphere. The connolly volume of the anionic ligand can be calculated after optimizing the structure of the anionic ligand, for example, using a Material Studio 6.0 Dmol3 to optimize the structure. Optimization of the structure of the anionic ligand can be carried out by MM2 (Molecular Mechanics Calculation) or PBE/DNP4.4. Thus, after optimizing the structure of the anionic ligand, the connolly radius was set to 1.0 Å to obtain a connolly volume.

For example, a case of calculating the radius of the acetate ion will be described. When the connolly volume of the acetate ion was determined by the above method, it was 54.8 Å. When the volume is assumed to be the volume of the sphere and the radius of the sphere is determined, it is about 2.36 Å, and this is taken as the radius of the acetate ion (coordination).

On the other hand, the radius of chloride ions or sulfate ions can be set as the ionic radius described in the second edition of the Chemical Handbook, edited by the Chemical Society of Japan (by Shannon and Pruitt). Prewitt)).

More preferably, the valence of the anionic ligand is less than the valence of the metal ion, and the radius of the anionic ligand is 2.0 Å or more (preferably 2.4 A or more).

The anionic ligand may be a carboxylate compound, a 1,3-dicarbonyl compound, a dithiocarboxylic acid or a carboxylate anion thereof, a sulfuric acid or a carboxylate anion thereof, a thioketonecarboxylic acid or a carboxylate thereof An anion, a 1,3-dithiocarbonyl compound, a nitrate ion, a halogen ion, or the like.

The carboxylate compound is preferably a compound represented by the following formula (7A), or An anion of a carboxylate compound represented by the following formula (7B).

In the formula (7A), RD1 represents a hydrogen group; and RD2 represents a hydrogen group, a hydrocarbon group having 1 to 10 carbon atoms or a hydroxyl group. In the formula (7B), RD2 represents a hydrogen group, a hydrocarbon group having 1 to 10 carbon atoms or a hydroxyl group. The hydrocarbon group having 1 to 10 carbon atoms may be an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms, and preferably a linear or branched alkyl group having 1 to 7 carbon atoms. In many cases, in the compound represented by the formula (7A), the hydroxyl group represented by -ORD1 is coordinated to the metal ion; and in the anion of the carboxylate compound represented by the formula (7B), O ^{- is} coordinated to the metal ion.

Examples of the anion of the carboxylate compound represented by the formula (7A) and the carboxylate compound represented by the formula (7B) include an alkylcarboxylic acid having 1 to 10 carbon atoms or a carboxy group thereof. An acid salt anion, an aryl carboxylic acid having 7 to 10 carbon atoms or a carboxylate anion thereof.

Examples of the alkyl carboxylic acid having 1 to 10 carbon atoms include formic acid (see the following formula (7A-1)), acetic acid (see the following formula (7A-2)), butyric acid, 2-ethylbutyric acid, 2,2-dimethylbutyric acid, 2-ethylhexanoic acid (refer to the following formula (7A-3)), 3-methylbutyric acid, 2,2-dimethylpropionic acid, etc., particularly preferably formic acid , acetic acid, 2-ethylhexanoic acid.

Examples of the arylcarboxylic acid having 7 to 10 carbon atoms include benzoic acid, naphthenic acid and the like.

The 1,3-dicarbonyl compound is preferably a compound represented by the formula (8).

R ₅ -(C=O)-CH=C(O)-R ₆ (8)

In the formula (8), R ₅ and R ₆ each independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms. The alkyl group having 1 to 10 carbon atoms may be a methyl group or an ethyl group. The aryl group having 6 to 10 carbon atoms may be a phenyl group or a naphthyl group. Examples of the 1,3-dicarbonyl compound include acetoacetate and the like.

Examples of the dithiocarboxylic acid or its carboxylate anion include an alkyl disulfide carboxylic acid having 1 to 10 carbon atoms or a disulfide carboxylate anion thereof, an aryl dithiocarboxylic acid having 7 to 15 carbon atoms or the like. A thiocarboxylate anion or the like.

Examples of the alkyl disulfidecarboxylic acid having 1 to 10 carbon atoms include dithioformic acid, dithioacetic acid, dithiopropionic acid, dithio-2-ethylhexanoic acid and the like.

Examples of the sulfuric acid or a carboxylate anion thereof include an alkylthiocarboxylic acid having 1 to 10 carbon atoms or an alkylthiocarboxylate anion thereof, an arylsulfuric acid having 7 to 15 carbon atoms or an arylsulfide thereof. Carboxylate anion and the like.

Examples of the alkylthiocarboxylic acid having 1 to 10 carbon atoms include sulfuric acid, sulfur-2-ethylhexanoic acid and the like.

[Chem. 21]

Examples of the thioketone carboxylic acid or a carboxylate anion thereof include an alkylthioketonecarboxylic acid having 1 to 10 carbon atoms or an alkylthioketone carboxylate anion thereof, and an arylthioketonecarboxylic acid having 7 to 15 carbon atoms or Its arylthione carboxylate anion and the like.

Examples of the alkylthioketonecarboxylic acid having 1 to 10 carbon atoms include thioket acetic acid, thioketone-2-ethylhexanoic acid and the like.

The 1,3-dithiocarbonyl compound is preferably a compound represented by the formula (9).

R ₇ -(C=S)-CH=C(S)-R ₈ (9)

In the formula (9), R ₇ and R ₈ each independently represent an alkyl group having 1 to 10 carbon atoms or an aryl group having 6 to 10 carbon atoms. The alkyl group having 1 to 10 carbon atoms may be a methyl group or an ethyl group. The aryl group having 6 to 10 carbon atoms may be a phenyl group or a naphthyl group. Examples of nitrate ions include NO ₃ ^- . Examples of the halogen ion include Br ^- and the like.

The number of atoms (the atoms which can be bonded to metal ions) selected from O, S, P, and halogen contained in the anionic ligand may be one or two or more. An anionic ligand containing two or more atoms bondable to a metal ion may be bonded to a metal ion via one atom, or may be bonded via two or more atoms. In order to form a ring with a metal ion, the metal complex (B) is easily stabilized electronically, and the hardening promoting property of the metal complex (B) is favorably maintained, and it is preferred that the anionic ligand is contained. The number of atoms bonded by metal ions is two or more.

An anionic ligand comprising two or more atoms which are bondable to a metal ion preferably forms a 3 to 7 membered ring with the metal ion. Preferable examples of such an anionic ligand include the carboxylate compound represented by the above formula (7A). The carboxylate compound represented by the formula (7A) can be bonded to a metal ion via any one of an oxygen atom constituting a carbonyl group or an oxygen atom adjacent to a carbonyl group.

Preferably, the metal complex (B) is coordinated to the metal ion respectively. A compound obtained by a tertiary amine represented by any one of the formulae (1) to (3) and a carboxylate compound represented by the above formula (7A).

The tertiary amine to be bonded to the metal ion may be any one of the following general formulae (1) to (3), or two or more kinds thereof.

In order to maintain the storage stability of the sheet-like epoxy resin composition of the present invention and to cure at a temperature at which deterioration of the organic EL element can be suppressed, the metal complex (B) is preferably of the formula (1) to The two kinds of amine compounds shown in (3) are mixed with the anion of two kinds of carboxylate compounds represented by the formula (7A) or two kinds of carboxylate compounds represented by the formula (7B). The complex. Specifically, a metal complex represented by the following formula (10) is preferred.

In the formula (10), Me represents -CH ₃ , Et represents -C ₂ H ₅ , and Bu represents -C ₄ H ₉ .

The sheet-like epoxy resin composition of the present invention contains a high molecular weight epoxy resin (A). When the high molecular weight epoxy resin (A) is hardened during storage, the flexibility of the sheet-like epoxy resin composition is easily impaired, so the metal complex (B) Requirement: The epoxy resin such as the high molecular weight epoxy resin (A) is not hardened during storage; that is, the sheet-like epoxy resin composition is required to have storage stability. On the other hand, when a sheet-like epoxy resin composition is used, the metal complex (B) is required to function as a curing accelerator for the epoxy resin. Two kinds of amine compounds represented by any one of the general formulae (1) to (3), two kinds of carboxylate compounds represented by the formula (7A), or two kinds of compounds represented by the formula (7B) The anion of the carboxylate compound, which is a complex of the metal ion, which is a complex of the metal ion, can improve the storage stability of the sheet-like epoxy resin composition and can be exhibited well in use. It is preferable as a function of a hardening accelerator.

In order to be easily dissolved in an epoxy resin or the like, the metal complex (B) is preferably close to the polarities. Further, in order to be easily dissolved in an epoxy resin or the like, the tertiary amine in the metal complex (B) is also preferably close to the polarities.

Whether a tertiary amine complexes formed with metal ions, can be by chemical shift of ¹ H NMR of the metal complex (B), tertiary amines, tertiary amine alone with the ¹ H NMR chemical shift Confirm by comparison. I.e., ¹ H NMR of a tertiary amine metal complex (B) in (CDCl ₃ In, 25 ℃, 270MHz) chemical shift with respect to the tertiary amine separate ¹ H NMR (CDCl ₃ In, 25 ℃, 270MHz The chemical shift is shifted by 0.05 ppm or more, preferably 0.1 ppm or more, and more preferably 0.4 ppm or more. By including the above peak, it is confirmed that the tertiary amine forms a complex with the metal ion. The upper limit of the amount of movement of the peak is not particularly limited, but is usually about 1 ppm, and more generally, it is 0.7 ppm.

Whether the tertiary amine in the sheet-like epoxy resin composition forms a complex with the metal ion (whether the sheet-like epoxy resin composition contains the metal complex (B)), or by the sheet-like epoxy resin The chemical shift of the ¹ H NMR of the composition derived from the chemical shift of the tertiary amine was confirmed in comparison with the chemical shift of the ¹ H NMR of the tertiary amine alone. In this case, similarly to the above, it is preferred to include a chemical shift of the tertiary amine from the chemical shift of the ¹ H NMR (CDCl ₃ , 25 ° C, 270 MHz) of the sheet-like epoxy resin composition relative to the third The monoamine is shifted by a chemical shift of ¹ H NMR (CDCl ₃ , 25 ° C, 270 MHz) to a peak of 0.05 ppm or more, preferably 0.1 ppm or more, more preferably 0.4 ppm or more. The upper limit of the amount of movement of the peak is also the same as described above, and may be about 1 ppm, preferably about 0.7 ppm.

Or whether the tertiary amine in the sheet-like epoxy resin composition forms a complex with the metal ion (whether the sheet-like epoxy resin composition contains the metal complex (B)), or by the pair of ring-shaped rings The chemical shift of ¹ H NMR of the oxy-resin composition was confirmed by comparison with the chemical shift of the metal complex (B) by ¹ H NMR alone. For example, if the chemical shift of the ¹ H NMR of the metal complex (B) is the same as the chemical shift of the metal complex (B) in the ¹ H NMR chemical shift, the sheet-like epoxy resin composition can be judged. Contains a metal complex (B).

It is considered that the peak shifted in ¹ H NMR is derived from a hydrogen atom whose electron state changes due to the coordination of the tertiary amine with the metal ion. It is considered that such a hydrogen atom is usually a hydrogen atom existing in the periphery of a conjugated system containing a nitrogen atom. For example, when the tertiary amine is an imidazole compound represented by the formula (1), the peak of movement in ¹ H NMR is mostly attributed to a hydrogen atom at the 4-position or the 5-position.

Around the hydrogen atoms present around the conjugated system containing a nitrogen atom The tertiary amine which does not have a bulky group is expected to be easily coordinated to the metal ion because the nitrogen atom contained in the conjugated system is easily accessible to the metal ion.

The content of the metal complex (B) in the sheet-like epoxy resin composition, the ring of the active functional group (tribasic amine group) of the metal complex (B) / the sheet-like epoxy resin composition The equivalent ratio of the oxy group is preferably from 0.003 to 0.3, more preferably from 0.008 to 0.3. From the viewpoint of improving the hardenability of the sheet-like epoxy resin composition, the above equivalent ratio is particularly preferably from 0.01 to 0.152. The metal complex (B) may contain only one metal complex or a combination of two or more metal complexes.

<Low molecular weight epoxy resin (C)>

The sheet-like epoxy resin composition of the present invention preferably further comprises a low molecular weight epoxy resin (C). The low molecular weight epoxy resin (C) is an epoxy resin having a weight average molecular weight of 100 to 1200, preferably an epoxy resin having a weight average molecular weight of 200 to 1100. The weight average molecular weight can be measured in the same manner as described above. The low molecular weight epoxy resin (C) having a weight average molecular weight of the above-mentioned range can sufficiently improve the fluidity of the sheet-like epoxy resin composition when the sheet-like epoxy resin composition is pressure-bonded, and can also be sufficiently improved. The adhesion of the sheet-like epoxy resin composition to the material to be crimped.

The epoxy equivalent of the low molecular weight epoxy resin (C) is preferably from 80 g/eq to 300 g/eq, more preferably from 90 g/eq to 200 g/eq.

The low molecular weight epoxy resin (C) is preferably a phenol type epoxy resin, more preferably a phenol type epoxy compound having a valence of 2 or more, or an oligomer containing a phenol derivative and epichlorohydrin as a monomer component.

Examples of the phenolic epoxy compound having a valence of 2 or more include a bisphenol epoxy compound, a phenol novolac epoxy compound, and a cresol novolak epoxy compound. Examples of the bisphenol type epoxy compound include a compound represented by the following formula (12). The following general formula (12) in the X-, R ₁ and P may be of the general formula described above with high molecular weight epoxy resin (A) shown in X (11) is the same as R ₁ and P.

Examples of the phenol derivative containing an oligomer of a phenol derivative and epichlorohydrin as a monomer component include bisphenol, hydrogenated bisphenol, phenol novolak, cresol novolac, and the like.

Preferable examples of the low molecular weight epoxy resin (C) include a bisphenol type epoxy compound or an oligomer in which bisphenol and epichlorohydrin are used as a monomer component. The low molecular weight epoxy resin (C) is more preferably an oligomer having a repeating number n of 2 to 4 in the above formula (11). Such an oligomer has high affinity with the high molecular weight epoxy resin (A).

Further, the repeating structural unit contained in the low molecular weight epoxy resin (C) may be the same as or different from the repeating structural unit contained in the high molecular weight epoxy resin (A).

Relative to the high molecular weight epoxy resin (A), the metal complex (B), and The total content of the decane coupling agent (D) is 100 parts by mass, and the content of the low molecular weight epoxy resin (C) is 1 part by mass to 100 parts by mass, preferably 5 parts by mass to 50 parts by mass. When the content ratio of the low molecular weight epoxy resin (C) is in the above range, the fluidity of the composition during thermocompression bonding of the sheet-like epoxy resin composition is sufficiently improved. Moreover, the sheet-like epoxy resin composition is sufficiently hardened.

<decane coupling agent (D)>

The sheet-like epoxy resin composition of the present invention may further comprise: 1) a decane coupling agent having an epoxy group, or 2) a decane coupling agent having a functional group reactive with an epoxy group. The reaction with an epoxy group means an addition reaction with an epoxy group. For example, when the sheet-like epoxy resin composition for sealing an organic EL element contains the decane coupling agent (D), the adhesion between the sheet-like epoxy resin composition and the substrate of the organic EL element is improved.

Further, a decane coupling agent having an epoxy group or a functional group reactive with an epoxy group is allowed to react with the epoxy resin in the sheet-like epoxy resin composition. Therefore, it is also preferable from the viewpoint that it is difficult to leave a low molecular weight component in the cured product of the sheet-like epoxy resin composition.

1) The decane coupling agent having an epoxy group is a decane coupling agent containing an epoxy group such as a glycidyl group, and examples thereof include γ-glycidoxypropyltrimethoxydecane and β-(3,4-epoxy). Cyclohexyl)ethyltrimethoxydecane, and the like.

2) A functional group reactive with an epoxy group includes, in addition to an amine group such as a primary amino group or a secondary amino group; a carboxyl group or the like, a group which can be converted into a functional group reactive with an epoxy group (for example, A) Acrylhydrazine, isocyanate, etc.). Examples of the decane coupling agent having such a functional group reactive with an epoxy group include: N-2-(aminoethyl)-3- Aminopropylmethyldimethoxydecane, N-2-(aminoethyl)-3-aminopropylmethyltrimethoxydecane, and the like.

The sheet-like epoxy resin composition of the present invention may further contain another decane coupling agent together with the above decane coupling agent. Examples of other decane coupling agents include vinyltriethoxydecane, vinyltrimethoxydecane, and the like. These decane coupling agents may be used alone or in combination of two or more.

The molecular weight of the decane coupling agent is preferably from 80 to 800. The content of the decane coupling agent is preferably from 0.05 part by mass to 30 parts by mass, more preferably from 0.1 part by mass to 20 parts by mass, even more preferably from 0.3 part by mass to 10 parts by mass per 100 parts by mass of the sheet-like epoxy resin composition. .

<Solvent (E)>

The sheet-like epoxy resin composition of the present invention may further contain a solvent (E) for uniformly mixing the above components (A) to (D). The solvent (E) particularly has a function of easily dispersing or dissolving the high molecular weight epoxy resin (A) uniformly.

The solvent (E) may be various organic solvents. Examples thereof include aromatic solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone; ether, dibutyl ether, tetrahydrofuran, dioxane, and ethylene glycol monoalkyl ether. Ethers such as ethylene glycol dialkyl ether and propylene glycol dialkyl ether; aprotic polar solvents such as N-methylpyrrolidone, dimethylimidazolidinone and dimethylformaldehyde; esters such as ethyl acetate and butyl acetate Wait. In particular, in terms of easily dissolving the high molecular weight epoxy resin (A), a ketone solvent (solvent having a ketone group) such as methyl ethyl ketone is preferred.

Solvent (E) with respect to the sheet-like epoxy resin composition of the present invention as a whole The content is preferably 50,000 ppm by mass or less, more preferably 30,000 ppm by mass or less. If the content of the solvent (E) in the sheet-like epoxy resin composition is large, there is a possibility that the solvent (E) may affect the material to be sealed. The content of the solvent (E) in the sheet-like epoxy resin composition can be measured, for example, by using an infrared ray (IR) absorption spectrum measuring apparatus (FT/IR-4100, manufactured by JASCO Corporation).

For example, when Methyl Ethyl Ketone (MEK) is contained as the solvent (E), the content of the solvent (E) can be determined by the following method.

1) A standard sample (sheet epoxy resin composition) for quantifying the amount of solvent by gas chromatography/mass spectrometry (GC-MS) is prepared in advance, and IR absorption spectrum is applied to the standard sample. Determination. The IR absorption spectrum of the standard sample, the MEK calculated C = O absorption peak (about 1710cm ^-1) with respect to the intensity ratio of the epoxy resin C = C absorption peak (about 1609cm ^-1) is.

2) Then, the measurement sample (sheet epoxy resin composition) was subjected to IR absorption spectrometry, and the C=O absorption peak (about 1710 cm ^-1 ) of MEK was calculated relative to the C=C absorption peak of the epoxy resin (about 1609 cm). ^-1 ) intensity ratio.

3) Calculate the ratio of the peak intensity ratio of the measured sample to the peak intensity ratio of the standard sample, and calculate the amount of the solvent contained in the measured sample.

<Other optional ingredients (F)>

The sheet-like epoxy resin composition of the present invention may further contain an optional component such as another resin component, a filler, a modifier, or a stabilizer, within a range not greatly impairing the effects of the invention. Examples of other resin components are: polyamine, polyamidoximine, polyurethane, polybutadiene, polychloroprene, polyether, polyester, styrene-butyl An ene-styrene block copolymer, a petroleum resin, a xylene resin, a ketone resin, a cellulose resin, a fluorine-based oligomer, a fluorene-based oligomer, a polysulfide-based oligomer, or the like. These may be included in only one type, and may also include a plurality of types.

Examples of the filler include glass beads, styrene polymer particles, methacrylate polymer particles, ethylene polymer particles, and propylene polymer particles. Fillers can comprise a plurality of types.

Examples of the modifier include a polymerization initiator, an ageing agent, a leveling agent, a wettability improver, a surfactant, a plasticizer, and the like. These can be used in combination. Examples of stabilizers include: ultraviolet absorbers, preservatives, and antibacterial agents. The modifier can comprise a plurality of types.

The sheet-like epoxy resin composition of the present invention can be produced by any method as long as the effects of the present invention are not impaired. The sheet-like epoxy resin composition of the present invention can be obtained, for example, by the following steps: 1) a step of preparing the component (A) to the component (E), and 2) dissolving the component (A) to the component (D) in the component (E). The step of obtaining a varnish of the resin composition at 30 ° C or lower, 3) the step of applying the varnish of the resin composition to a sheet form, and 4) drying the resin composition applied in a sheet form. A step of.

In the step of 2), the component (A) to the component (E) may be mixed at once, or the component (A) may be dissolved and mixed in the component (E), and the other component may be added and mixed. Examples of the mixing method include a method of charging the components into a flask for stirring, a method of kneading by three rolls, and the like.

The varnish of the resin composition obtained in the step of 2) is viscous at 25 ° C The degree is preferably 0.01 Pa. s~100Pa. s. When the viscosity of the varnish of the resin composition is in the above range, the coating property of the varnish of the resin composition in the step 3) is improved, and the sheet can be easily formed. The above viscosity is a value measured at 25 ° C by an E-type viscometer (RC-500 manufactured by Toki Sangyo Co., Ltd.). The viscosity of the varnish of the resin composition can be adjusted by the amount of the component (E) or the like.

The coating method in the step of 3) is not particularly limited, and examples thereof include a method using screen printing, a dispenser, and various coating rolls. Further, the type of the substrate is not particularly limited, and for example, a known release film or the like can be used. Further, the coating thickness of the mixture is appropriately selected depending on the film thickness of the target sheet-like epoxy resin composition. For example, the film thickness of the sheet-like epoxy resin composition after drying is set to, for example, 1 μm to 100 μm.

The drying temperature and the drying time in the step of 4) are such that the high molecular weight epoxy resin (A) or the low molecular weight epoxy resin (C) contained in the above resin composition is not cured, and the solvent (E) can be used. The temperature or time until the desired amount or less is removed by drying. The drying temperature is, for example, 20 ° C to 70 ° C, and the drying time is, for example, about 10 minutes to 3 hours. Specifically, it is preferred that the coating film is dried in an inert gas atmosphere such as a nitrogen atmosphere at 30 to 60 ° C for about 10 minutes, and then further dried under vacuum for about 2 hours. Thus, by further vacuum drying, the solvent or moisture contained in the sheet can be removed at a relatively low drying temperature. The drying method is not particularly limited, and examples thereof include hot air drying, vacuum drying, and the like.

<Physical properties of sheet-like epoxy resin composition>

(thickness)

The thickness of the sheet-like epoxy resin composition of the present invention also depends on its use, for example When used as a sealing material for an optical semiconductor device, the thickness is, for example, preferably from 1 μm to 100 μm, more preferably from 10 μm to 30 μm, still more preferably from 20 μm to 30 μm.

(water content)

The water content of the sheet-like epoxy resin composition of the present invention is preferably 0.1% by mass or less, and more preferably 0.06% by mass or less, from the viewpoint of suppressing the influence of moisture on the material to be sealed. The reason is that when the optical semiconductor such as an organic EL element is sealed by the sheet-like epoxy resin composition of the present invention, deterioration of the photo-semiconductor due to moisture is suppressed.

The moisture content of the sheet-like epoxy resin composition is, for example, about 0.1 g of a sample piece of a sheet-like epoxy resin composition, and the moisture generated by heating to 150 ° C is measured by a Karl Fischer moisture meter. The amount was determined (solid gasification method).

(melting point)

The sheet-like epoxy resin composition of the present invention preferably has a moderate fluidity at a thermocompression bonding temperature. When the sheet-like epoxy resin composition of the present invention is sealed with an optical semiconductor such as an organic EL element, the sheet-like epoxy resin composition is heated and fluidized, and the organic EL is smoothly filled. The unevenness of the surface of the photo-semiconductor such as an element excludes the gap.

The fluidity at the time of thermocompression bonding of the sheet-like epoxy resin composition can be judged by the melting point. The melting point is a temperature at which fluidity is exhibited when the sheet-like epoxy resin composition is heated, and is preferably 30 ° C to 100 ° C, more preferably 40 ° C to 80 ° C.

When the melting point is less than 30 ° C, when the thermal transfer (thermocompression bonding) or thermal curing is performed and the sealing is performed, the fluidity of the sheet-like epoxy resin composition is excessively large, and sag is likely to occur, and it is difficult to manage the cured product. The case of film thickness. On the other hand, if melting When the point exceeds 100 ° C, the workability at the time of thermal transfer is deteriorated. Therefore, a gap is easily formed between the sheet-like epoxy resin composition and the material to be sealed, or the sealing material (for example, an organic EL element) is adversely affected by heating. On the other hand, when the melting point is 30° C. to 100° C., it is possible to suppress formation of a gap between the sheet-like epoxy resin composition and the element, and to obtain good adhesion.

When the melting point of the sheet-like epoxy resin composition fluctuates greatly during storage, the temperature or pressure at the time of sealing the photo-semiconductor or the like using the sheet-like epoxy resin composition must be largely changed depending on the fluctuation. On the other hand, in the sheet-like epoxy resin composition of the present invention in which the melting point does not largely fluctuate during storage, the conditions for sealing the optical semiconductor or the like can be made constant, so that the efficiency of the sealing step of the optical semiconductor or the like can be improved. Further, when the melting point can be maintained at a somewhat low temperature, the adhesion to the element or the substrate is improved, and the water vapor barrier property at the bonding interface is hard to be lowered. For example, after the sheet-like epoxy resin composition is produced, the amount of change in the melting point after storage for 7 days at 23 ° C and 60 RH% is preferably 5 ° C or lower, more preferably 1 ° C or lower.

The melting point can be measured by pressing a sheet-like epoxy resin composition (thickness: 15 μm) onto a glass plate placed on a hot plate and then starting to melt the resin composition. Specifically, the sheet-like epoxy resin composition was cut into a strip test piece having a length of about 40 mm and a width of about 5 mm. After the sheet-like epoxy resin composition of the test piece was adhered to a glass plate placed on a hot plate and heated, the test piece was slowly peeled off from the glass plate in a 180-degree direction. Starting from the set temperature of the heating plate at 35 ° C, the test piece is re-prepared for every 1 ° C increase in temperature, and the operation is repeated to maximize the adhesive peeling property of the sheet-like epoxy resin composition at the time of peeling. The temperature is taken as the melting point.

(hardenability)

The curing speed of the sheet-like epoxy resin composition of the present invention is preferably a somewhat high curing rate. The reason is that the workability when bonding with the material to be sealed is improved. The so-called rapid hardening means, for example, hardening within 120 minutes under heating conditions (80 ° C to 100 ° C).

Whether or not the sheet-like epoxy resin composition is hardened can be judged by finger contact to confirm whether or not the sheet-like epoxy resin composition has been hardened and gelled on a hot plate. Further, whether or not the sheet-like epoxy resin composition is cured is also determined based on the conversion ratio of the epoxy group. The conversion ratio of the epoxy group can be determined by measuring the IR spectrum of the sheet-like epoxy resin composition before the curing reaction and the curing reaction, and determining the rate of reduction of the epoxy group in the IR spectrum. The hardenability of the sheet-like epoxy resin composition can be controlled by adjusting the amount of the hardening accelerator.

(transparency)

When the sheet-like epoxy resin composition of the present invention is used for a sealing material of an optical semiconductor such as an organic EL device, etc., from the viewpoint of light output from the organic EL panel, transparency may be required for the sealing member. Therefore, the light transmittance of the sheet-like epoxy resin composition and the cured product thereof at a thickness of 40 μm and a wavelength of 550 nm is preferably 90% or more, and more preferably 93% or more.

The light transmittance of the cured product of the sheet-like epoxy resin composition can be measured by the following procedure.

1) Forming a sheet-like epoxy resin composition having a dry thickness of 40 μm on a glass plate (S9213 manufactured by Songlang Glass, thickness 1.2mm, 76mm × 52mm). The sheet-like epoxy resin composition on the glass plate was heated in an oven at 100 ° C for 2 hours to prepare a cured product.

2) The transmittance of the glass plate on which the cured product of the sheet-like epoxy resin composition was formed at a wavelength of 550 nm was measured using an ultraviolet-visible spectrophotometer (Shimadzu Corporation UV-2550). In the measurement, the transmittance of the glass plate alone was taken as a baseline.

The light transmittance of the sheet-like epoxy resin composition (before curing) can be measured in the same manner except that the sheet-like epoxy resin composition of the above 1) is not cured.

(the moisture permeability of the hardened material)

When the sheet-like epoxy resin composition of the present invention is used as a sealing material for an optical semiconductor such as an organic EL device, it is preferably a cured product in order to suppress deterioration of the optical semiconductor device such as an organic EL device due to moisture. Low moisture permeability. Therefore, the moisture permeability of the cured product of the sheet-like epoxy resin composition of the present invention is preferably 60 g/m ² . Below 24h, more preferably 30g/m ² . Below 24h. The moisture permeability can be determined by measuring a cured product of a sheet-like epoxy resin composition of 100 μm under conditions of 60° C. and 90% RH in accordance with JIS Z0208.

(Tg of hardened material)

The cured product of the sheet-like epoxy resin composition of the present invention preferably has a Tg of 80 ° C or higher. The Tg of the cured product can be measured by using a Thermomechanical Analyzer (TMA) (TMA/SS6000 manufactured by Seiko Instruments Co., Ltd.) at a temperature rising rate of 5 ° C /min, and It is obtained from its inflection point.

(XPS characteristics of hardened materials)

The cured product of the sheet-like epoxy resin composition of the present invention is detected in a spectrum measured by X-ray photoelectron spectroscopy (XPS) from a source selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr. The peak of one or more kinds of metal atoms of the composition group and the peak derived from the nitrogen atom are preferably metal atoms of the detected metal atom and nitrogen atom: nitrogen atom = 1:0.5 to 1:6.0. The molar ratio of the nitrogen atom to the metal atom of 1 mole may depend on the content of the tertiary amine relative to the metal ion in the metal complex (B). Further, the metal atom is preferably Zn, and the content thereof is preferably from 0.5% by mass to 15% by mass in the cured product.

The XPS measurement can be carried out using AXIS-NOVA (manufactured by KRATOS). The light source was set to monochromatize Al Kα; the diameter of the measurement area was set to 100 μm.

2. Sealing sheet

The sheet for sealing of the present invention contains a layer containing the sheet-like epoxy resin composition of the present invention. For example, the sheet for sealing of the present invention may comprise a base film, a layer comprising the sheet-like epoxy resin composition of the present invention formed on the base film, and a sheet-like epoxy resin composition formed as needed. Protective film on it.

As described above, the water content of the layer containing the sheet-like epoxy resin composition is preferably 0.1% by mass or less, and more preferably 0.06% by mass or less, from the viewpoint of suppressing the influence of moisture on the material to be sealed. In particular, the organic EL element is easily deteriorated by moisture. Therefore, when the organic EL element is sealed by the sheet for sealing, it is preferred to reduce the water content as much as possible. Example of moisture content of a layer containing a sheet-like epoxy resin composition for a sheet for sealing The sheet for sealing can be lowered by heat drying or the like under vacuum.

When the sheet-like epoxy resin composition is used for a sealing material or the like of an optical semiconductor device such as an organic EL device, transparency may be required for the sealing member from the viewpoint of light output property of the organic EL panel. Therefore, the light transmittance of the layer containing the sheet-like epoxy resin composition at a thickness of 40 μm and a wavelength of 550 nm is preferably 90% or more, and more preferably 93% or more.

The melting point, solvent content and thickness of the layer containing the sheet-like epoxy resin composition may also be as described above.

Examples of the base film or the protective film include a known release film, preferably a film having moisture barrier properties or gas barrier properties, and more preferably polyethylene terephthalate. The thickness of the base film is also dependent on the material of the film, and is about 50 μm, for example, in terms of the followability to the material to be sealed such as the organic EL element.

The protective film is preferably laminated on the layer containing the sheet-like epoxy resin composition of the present invention. The laminate is preferably carried out, for example, at a temperature of about 60 ° C using a laminator. The thickness of the protective film is, for example, about 20 μm.

The sheet for sealing of the present invention may further contain a gas barrier layer as needed. The gas barrier layer may be a layer that suppresses moisture or gas that deteriorates the organic EL element, such as moisture in the outside air, from passing through the organic EL panel. Such a gas barrier layer may be disposed at any position other than the surface in contact with the organic EL element, but is preferably disposed between the base film and the layer containing the sheet-like epoxy resin composition of the present invention.

The material constituting the gas barrier layer is not particularly limited. Examples of materials constituting the gas barrier layer include: Al, Cr, Ni, Cu, Zn, Si, Fe, Ti, Ag, Au, Co; oxides of the metals; nitrides of the metals; nitrogen oxides of the metals, and the like. The gas barrier layer may contain one metal material or two or more metal materials. Further, the gas barrier layer may also contain a resin material.

For example, the gas barrier layer for the sheet for sealing of the sealing of the organic EL element of the bottom emission type is preferably a layer having a high light reflectance, and for example, a layer containing Al, Cu or the like is preferable. On the other hand, the gas barrier layer for the sealing sheet for sealing of the organic EL element of the top emission type is preferably a layer having a high light transmittance, and may be, for example, polyethylene terephthalate (Polyethylene Terephthalate). PET), polycarbonate (Polycarbonate, PC) and the like. The thickness of the gas barrier layer may be from about 10 μm to about 3000 μm.

The sheet for sealing having a gas barrier layer can be produced by forming a gas barrier layer on a base film and then forming a layer containing the sheet-like epoxy resin composition of the present invention. The method for forming the gas barrier layer is not particularly limited, and includes, as a dry process, various physical vapor deposition (PVD) methods such as vacuum evaporation, sputtering, ion plating, and plasma chemistry. A CVD method such as a chemical vapor deposition (CVD), as a wet process, includes a plating method, a coating method, and the like.

FIG. 1 is a view showing a preferred example of the configuration of a sheet for sealing. As shown in FIG. 1, the sheet 10 for sealing has a base film 12, a layer 16 including a sheet-like epoxy resin composition disposed on the base film 12, and a sheet-like epoxy resin composition. The protective film 18 on the layer 16.

Fig. 2 is a view showing another preferred example of the structure of the sheet for sealing. figure 2 The sealing sheet can be constructed in the same manner as in Fig. 1 except that the gas barrier layer 14 is further contained. In other words, the sheet for sealing 10' includes a gas barrier layer 14 formed on the base film 12, a layer 16 including a sheet-like epoxy resin composition disposed on the gas barrier layer 14, and a sheet-like ring disposed thereon. A protective film 18 on the layer 16 of the oxy-resin composition.

In the sealing sheet 10 and the sheet 10 for sealing, for example, after the protective film 18 is peeled off, the exposed layer 16 including the sheet-like epoxy resin composition and the display substrate on which the optical semiconductor device such as the organic EL element is disposed can be used. The way the contact is configured is used.

In order to maintain the water content of the layer containing the sheet-like epoxy resin composition at a constant level or less, the sheet for sealing of the present invention is preferably stored together with a desiccant such as silicone.

3. Use of sealing sheet

The sheet for sealing of the present invention is used as a sealing member by hardening a layer containing a sheet-like epoxy resin composition. The material to be sealed which is the object to be sealed is not particularly limited, and is preferably an optical semiconductor device, for example. Examples of the optical semiconductor device include an organic EL display panel having an organic EL device or an organic EL illumination; a liquid crystal display, an LED, and the like. Hereinafter, an example in which the sheet for sealing of the present invention is used for sealing an organic EL element of an organic EL device will be described.

The organic EL device of the present invention comprises an organic EL device and a cured layer of the sheet-like epoxy resin composition of the present invention which is in contact with and sealed with the organic EL device.

Specifically, the organic EL device of the present invention includes a substrate (display substrate) on which an organic EL element is disposed, an opposite substrate that is paired with the display substrate, and a configuration A sealing member that seals the organic EL element between the display substrate and the opposite substrate. The sealing member may be a cured layer of the sheet-like epoxy resin composition of the present invention. As described above, a member in which a sealing member is filled in all or a part of a space formed between the organic EL element and the sealing substrate is referred to as a face-sealed organic EL device.

The adhesive force of the sealing member containing the cured product of the sheet-like epoxy resin composition of the present invention and the material to be sealed is preferably 300 gf / 15 mm or more.

The adhesion of the cured product to the counter substrate (glass substrate) as the material to be sealed can be measured by the following method.

1) A sheet-like epoxy resin composition (thickness: about 15 μm) was formed on the aluminum foil side of a film (product name: ALPET) obtained by laminating an aluminum foil and PET, and dried. Using a roll laminator (manufactured by MCK Co., Ltd., MRK-650Y type), the glass substrate (glass according to JIS R3202, 100 mm × 25 mm × 2 mm) was at a speed of 0.3 m/min and the cylinder pressurization pressure was Under the condition of heating at 0.2 MPa and a roll temperature of about 90 ° C, the sheet-like epoxy resin composition was thermocompression bonded to obtain a laminate.

2) The obtained laminate was heated at 80 ° C for 30 minutes in an oven to harden the sheet-like epoxy resin composition.

3) Then, the laminate was cut into a width of 15 mm, and the glass substrate and the sheet-like epoxy resin were measured by a peeling tester (device name: STROGRAPH ES, manufactured by Toyo Seiki Seisakusho Co., Ltd., range: 50 mm/min.). 90 degree peel strength of the cured product of the composition. In the present invention, the 90-degree peel strength is used as the adhesion.

3 is a view schematically showing a top emission structure and a surface-sealed organic EL A cross-sectional view of the device. As shown in FIG. 3, the organic EL device 20 is sequentially laminated with a display substrate 22, an organic EL element 24, and an opposite substrate (transparent substrate) 26, and a periphery of the organic EL element 24 and an opposite substrate (transparent substrate) 26 The sealing member 28 is filled between. In the organic EL device of the present invention, the sealing member 28 in Fig. 3 serves as a cured product of the sheet-like epoxy resin composition of the present invention.

The display substrate 22 and the counter substrate 26 are generally a glass substrate or a resin film, and a glass substrate or a transparent resin film which is transparent to at least one of the display substrate 22 and the counter substrate 26 (here, the counter substrate 26). Examples of such a transparent resin film include an aromatic polyester resin such as polyethylene terephthalate or the like.

The organic EL element 24 laminates the cathode reflective electrode layer 30 (including aluminum or silver), the organic EL layer 32, and the anode transparent electrode layer 34 (including indium tin oxide (ITO) or indium zinc oxide from the display substrate 22 side. (Indium Zinc Oxide, IZO), etc.). The cathode reflective electrode layer 30, the organic EL layer 32, and the anode transparent electrode layer 34 can be formed by vacuum deposition, sputtering, or the like.

The organic EL device using the cured product of the sheet-like epoxy resin composition of the present invention as a sealing member can be produced by any method. For example, the organic EL device of the present invention can be produced by the steps of: preparing a substrate on which an organic EL element is formed; thermocompression bonding the sheet-like epoxy resin composition of the present invention to the substrate or the like, and including the present invention The step of covering the organic EL element with the layer of the sheet-like epoxy resin composition of the invention; the step of hardening the layer containing the sheet-like epoxy resin composition by thermocompression bonding, and sealing the surface of the organic EL element.

Specifically, it is manufactured through the following steps: 1) Obtaining an organic configuration a display substrate 22 of the EL element 24, a layer including the layer of the sheet-like epoxy resin composition of the present invention, and a laminate of the opposite substrate (transparent substrate) 26; 2) a sheet-like epoxy comprising the obtained laminate The step of thermocompression bonding the layer of the resin composition; 3) the step of hardening the thermocompression-bonded layer containing the sheet-like epoxy resin composition. Each step may be carried out according to a known method.

In the step of 1), after the sheet-like epoxy resin composition is placed (or transferred) on the display substrate 22 on which the organic EL element 24 is disposed, it can be on the layer containing the sheet-like epoxy resin composition. A laminated body (method of (i)) is obtained by superposing the opposing substrate (transparent substrate) 26 as a pair.

In this case, a layer containing a sheet-like epoxy resin composition in which the protective film of the sealing sheet having a protective film is peeled off and exposed is placed on the organic EL element, and then the substrate film is peeled off and transferred; The layer containing the sheet-like epoxy resin composition of the sheet for sealing without a protective film is directly placed on the organic EL element by a roll bonding machine or the like.

Alternatively, a layer including the sheet-like epoxy resin composition of the present invention is placed on the counter substrate 26 in advance; and it is bonded to the display substrate 22 on which the organic EL element 24 is formed to obtain a laminate (( Ii) method). This method is effective, for example, in the case where the substrate (or the base film) of the sheet for sealing is not peeled off, and is directly incorporated into the organic EL device together with the layer containing the sheet-like epoxy resin composition.

In the step of 2), the layer containing the sheet-like epoxy resin composition is thermocompression bonded at 50 ° C to 110 ° C by using a vacuum laminator device, and the organic EL element is composed of a sheet-like epoxy resin. Thermocompression bonding of the layers of the object, and display substrate 22 The counter substrate 26 is thermocompression bonded. In this case, it is preferred to heat the organic EL element side to 50 to 110 ° C in advance, and to bond the organic EL element to the sheet-like epoxy resin composition.

In the step of 3), for example, the layer containing the sheet-like epoxy resin composition is completely cured at a curing temperature of 80 ° C to 100 ° C. The heat curing is preferably carried out at a temperature of from 80 ° C to 100 ° C for about 0.1 hours to 2 hours. In addition, the reason why the temperature at the time of heat curing is 100 ° C or less is that the organic EL element is not damaged.

Further, in order to reduce the moisture permeability to the organic EL element, a passivation layer is formed on the layer containing the sheet-like epoxy resin composition of the present invention or a cured product thereof, which is also a preferred embodiment.

The passivation layer is preferably an inorganic compound layer formed into a film in a plasma environment. The film formation in a plasma environment is, for example, a film formed by a plasma CVD method, but is not particularly limited, and can be formed by a sputtering method or a vapor deposition method. The material of the passivation layer is preferably a transparent inorganic compound, and examples thereof include cerium nitride, cerium oxide, SiONF, and SiON, but are not particularly limited. The thickness of the passivation layer is preferably from 0.1 μm to 5 μm. The passivation layer may be formed in contact with the cured layer of the sheet-like epoxy resin composition of the present invention.

In the sheet-like epoxy resin composition of the present invention, deterioration of an optical semiconductor such as an organic EL element tends to be less likely to occur. The reason is not necessarily clear, but it is presumed as follows. In other words, when the tertiary amine contained in the composition is in a state of being easily moved, the tertiary amine interacts with the metal constituting the charge transport layer or the light-emitting layer of the organic EL element, and the state of the organic EL element is changed, which is easy. Deterioration of the components. On the other hand, the tertiary amine contained in the sheet-like epoxy resin composition of the present invention forms a complex with a metal ion in advance, and thus the peripheral volume of the tertiary amine becomes large. Therefore speculated that tertiary amines and organic The interaction between the charge transport layer or the light-emitting layer of the EL element is hard to occur, and deterioration of the organic EL element or the like can be suppressed.

Whether or not deterioration of such a component occurs can be evaluated by the following method. That is, an organic EL device was produced by a vapor deposition method. After the composition of the present invention was pressure-bonded to the produced member, it was thermally hardened to seal the element, and Sample 1 was obtained. On the other hand, the sample 2 was obtained by sealing (sealed) the periphery of the produced member in the same manner by the composition of the present invention in such a manner as not to come into contact with the member. Further, the initial luminescence characteristics, lifetime, and reliability of Sample 1 and Sample 2 were measured, and the two were compared. If there is no difference in the evaluation results of the two, it can be judged that there is no deterioration of the element due to the interaction between the sheet-like epoxy resin composition and the element. Specifically, it can also be evaluated by the same method as the deterioration test method described in International Publication No. 2010/035502.

Example

High molecular weight epoxy resin (A)

<bisphenol F type epoxy resin>

jER4005 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 7582, epoxy equivalent is 1070g/eq

jER4010 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 39102, epoxy equivalent is 4400g/eq

<Bisphenol A/bisphenol F type epoxy resin>

jER4275 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 58287, epoxy equivalent is 9200 g/eq, (number of bisphenol F type structural units in one molecule): (Number of bisphenol A type structural units in one molecule) = 75:25

<phenoxy epoxy resin>

jER1256 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 58688, epoxy equivalent is 8500g/eq

Metal complex (B)

<Synthesis of Metal Complex (B-1)>

768.19 g (2.18 mol) of bis(2-ethylhexanoic acid) zinc was placed in a 5 L flask, and 1500 g of isopropyl alcohol was added thereto, and the mixture was stirred at about 150 rpm under normal temperature and normal pressure. Then, after confirming that the bis(2-ethylhexanoate)zinc was completely dissolved, 1,2-DMZ (1,2-dimethylimidazole) 210 g (2.18 mol) was added, and stirring was continued. Then, 1,2-DMZ 42 g (0.44 mol) was further added, and stirring was continued. Then, the stirring was stopped, and the resulting solution was transferred to a 3 L flask, and isopropyl alcohol was distilled off by evaporation to obtain a liquid metal complex (B-1). The molar ratio of the tertiary amine to the metal ion is 1.2.

The ¹ H NMR of the obtained metal complex (B-1) was measured.

_{^{1 H NMR (270MHz, CDCl 3}} ): δ 0.82 (t, J = 6.8Hz, 12H), 1.18-1.23 (m, 8H), 1.30-1.57 (m, 8H), 2.22 (td, J = 6.9Hz, 3.0 Hz, 2H), 2.51 (s, 3.7H), 3.57 (s, 3.7H), 6.76 (s, 1.2H), 7.06 (s, 1.2H).

Then, ¹ H NMR of 1,2-DMZ (1,2-dimethylimidazole) was measured.

¹ H NMR (270 MHz, CDCl ₃ ): δ 2.34 (s, 3H), 3.54 (s, 3H), 6.76 (s, 1H), 6.85 (s, 1H).

Based on the comparison of the ¹ H NMR shift of the metal complex (B-1) with the ¹ H NMR shift of 1,2-DMZ (1,2-dimethylimidazole), the peak of the hydrogen atom belonging to the 5-position is presumed. (6.85 → 7.06) move. In the following formula, the position of the hydrogen atom attributed to the peak of the movement confirmed is indicated by ○.

<Synthesis of Metal Complex (B-2)>

The tertiary amine was changed to 1B2PZ (1-benzyl-2-phenylimidazole), and the bis(2-ethylhexanoate) zinc or the third was changed in such a manner that the molar ratio of the tertiary amine to the metal ion was 0.2. In addition to the amount of the amine substituted, the liquid metal complex (B-2) was obtained in the same manner as the synthesis of the metal complex (B-1).

The ¹ H NMR of the obtained metal complex (B-2) was measured.

¹ H NMR (270 MHz, CDCl ₃ ): δ 0.82 (t, J = 7.8 Hz, 12H), 1.15-1.25 (m, 8H), 1.29-1.61 (m, 8H), 2.23 (td, J = 8.4, 5.7 Hz, 2H), 5.14 (s, 0.4H), 7.01 (d, J = 1.4 Hz, 0.2H), 7.07 (dd, J = 6.5, 1.6 Hz, 0.4H), 7.27 (d, J = 3.8 Hz, 0.2H), 7.33-7.45 (m, 1.2H), 7.58-7.61 (m, 2H).

Then, ¹ H NMR of 1B2PZ (1-benzyl-2-phenylimidazole) was measured.

_{^{1 H NMR (270MHz, CDCl 3}} ): δ 5.18 (s, 2H), 6.93 (d, J = 3.2Hz, 1H), 7.03 (dd, J = 3.2,1.4Hz, 2H), 7.18 (d, J = 3.8 Hz, 1H), 7.23 - 7.41 (m, 6H), 7.51 - 7.58 (m, 2H).

Based on the comparison of the ¹ H NMR shift of the metal complex (B-2) with the ¹ H NMR shift of 1B2PZ (1-benzyl-2-phenylimidazole), the peak of the hydrogen atom attributable to the 5-position was presumed (7.18). →7.27), the hydrogen atom of the phenyl group (7.23-7.41→7.33-7.45), and the hydrogen atom of the phenyl group (7.51-7.58→7.58-7.61) move. In the following formula, the position of the hydrogen atom attributed to the peak of the movement confirmed is indicated by ○.

<Synthesis of Metal Complex (B-3)>

The tertiary amine was changed to 1BMI12 (1-isobutyl-2-methylimidazole), and the bis(2-ethylhexanoate) zinc was changed in such a manner that the molar ratio of the tertiary amine to the metal ion was 0.8. A liquid metal complex (B-3) was obtained in the same manner as the metal complex (B-1) except for the amount of the tertiary amine to be charged.

The ¹ H NMR of the obtained metal complex (B-3) was measured.

¹ H NMR (270 MHz, CDCl ₃ ): δ 0.83 (t, J = 7.0 Hz, 12H), 0.91 (t, J = 4.1 Hz, 3H), 0.94 (d, J = 6.5 Hz, 3H), 1.18-1.26 (m, 8H), 1.26-1.58 (m, 8H), 2.03 (qt, J = 13.5, 0.5 Hz, 1H), 2.23 (td, J = 4.8 Hz, 1.9 Hz, 2H), 2.50 (s, 3H) , 3.63 (d, 7.3 Hz, 2H), 6.74 (d, J = 9.7 Hz, 1H), 7.10 (d, J = 1.4 Hz, 1H).

Then, ¹ H NMR of 1BMI12 (1-isobutyl-2-methylimidazole) was measured.

¹ H NMR (270 MHz, CDCl ₃ , standard substance tetramethyl decane (TMS)): δ 0.90 (t, J = 4.1 Hz, 3H), 0.91 (d, J = 6.5 Hz, 3H), 1.97 (qt, J =13.5, 0.5 Hz, 1H), 2.35 (s, 3H), 3.61 (d, J = 7.3 Hz, 2H), 6.77 (d, J = 1.4 Hz, 1H), 6.87 (d, J = 1.4 Hz, 1H) ).

Based on the comparison of the ¹ H NMR shift of the metal complex (B-3) with the ¹ H NMR shift of 1BMI12 (1-isobutyl-2-methylimidazole), the hydrogen atom belonging to the methyl group at the 2-position was presumed. The peak value (2.35 → 2.50) shifts with the peak value (6.87 → 7.10) of the hydrogen atom belonging to the 5-position. In the following formula, the position of the hydrogen atom attributed to the peak of the movement confirmed is indicated by ○.

<Synthesis of Metal Complex (B-4)>

The tertiary amine was changed to 1MI (1-methylimidazole), and the amount of bis(2-ethylhexanoate) zinc or tertiary amine was changed in such a manner that the molar ratio of the tertiary amine to the metal ion was 2.0. Other than this, a liquid metal complex (B-4) was obtained in the same manner as the metal complex (B-1).

The ¹ H NMR of the obtained metal complex (B-4) was measured.

_{^{1 H NMR (270MHz, CDCl 3}} ): δ 0.89 (t, J = 7.6Hz, 12H), 1.22-1.30 (m, 8H), 1.42-1.67 (m, 8H), 2.32 (td, J = 6.9Hz, 3.0 Hz, 2H), 3.69 (s, 6H), 6.84 (s, 2H), 7.37 (s, 2H), 8.15 (s, 2H).

Then, ¹ H NMR of 1MI (1-methylimidazole) was measured.

_{^{1 H NMR (270MHz, CDCl 3}} , standard substance TMS): δ 3.66 (s, 3H), 6.87 (s, 1H), 7.02 (s, 1H), 7.40 (s, 1H).

According to the comparison of the ¹ H NMR shift of the metal complex (B-4) with the ¹ H NMR shift of 1MI (1-methylimidazole), it is presumed that the peak of the hydrogen atom belonging to the 2-position (7.40→8.15) and the attribution The peak of the hydrogen atom at the 4-position (7.02 → 7.37) moves. In the following formula, the position of the hydrogen atom attributed to the peak of the movement confirmed is indicated by ○.

<Synthesis of Metal Complex (B-5)>

61.5 g (0.20 mol) of zinc benzoate was placed in a 1 L flask, and 160 g of isopropyl alcohol was added thereto, and the mixture was stirred at about 150 rpm under normal temperature and normal pressure. Then, after confirming that zinc benzoate was completely dissolved, 19.2 g (0.20 mol) of 1,2-DMZ (1,2-dimethylimidazole) was added, and stirring was continued. Then, the stirring was stopped, and the resulting solution was transferred to a 1 L flask, and isopropanol was distilled off by evaporation to obtain a liquid metal complex (B-5). The molar ratio of the tertiary amine to the metal ion is 1.0.

The ¹ H NMR of the obtained metal complex (B-5) was measured.

¹ H NMR (270MHz, CDCl ₃ , standard material TMS): δ 2.51 (s, 3H), 3.72 (s, 3H), 6.87 (s, 1H), 6.97 (s, 1H), 7.66-7.79 (m, 6H) ), 8.21 (d, J = 0.5 Hz, 4H).

¹ H NMR Comparative displaced metal complex according to (B-5) ¹ H NMR displacement of 1,2-DMZ (1,2- dimethylimidazole), the apparent peak attributable to four hydrogen atoms and The peaks of the hydrogen atoms belonging to the 5-position shift only the amounts shown in Table 1, respectively.

<Synthesis of Metal Complex (B-6)>

Into a 1 L flask, 52.7 g (0.20 mol) of zinc acetonate zinc was added, and 160 g of isopropyl alcohol was added thereto, and the mixture was stirred at about 150 rpm under normal temperature and normal pressure. Then, after confirming that the zinc benzoate was completely dissolved, 19.2 g (0.20 mol) of 1,2-DMZ (1,2-dimethylimidazole) was added, and stirring was continued. Then, the stirring was stopped, and the resulting solution was transferred to a 1 L flask, and isopropyl alcohol was distilled off by evaporation to obtain a liquid metal complex (B-6). The molar ratio of the tertiary amine to the metal ion is 1.0.

The ¹ H NMR of the obtained metal complex (B-6) was measured.

_{^{1 H NMR (270MHz, CDCl 3}} , standard substance TMS): δ 2.24 (s, 6H), 2.27 (s, 6H), 2.51 (s, 3H), 3.72 (s, 3H), 6.19 (s, 2H), 6.87(s,1H), 6.97(s,1H).

According to the comparison of the ¹ H NMR shift of the metal complex (B-6) with the ¹ H NMR shift of 1,2-DMZ (1,2-dimethylimidazole), the peak value of the hydrogen atom belonging to the 4-position is known. The peaks of the hydrogen atoms belonging to the 5-position shift only the amounts shown in Table 1, respectively.

The composition of the obtained metal complex (B-1) to metal complex (B-6) and the peak shift amount of ¹ H NMR are summarized in Table 1. The numerical values of the metal ion, the anionic ligand, and the tertiary amine in the column of the metal complex (B) in the table indicate the mass ratio.

Low molecular weight epoxy resin (C)

<bisphenol F type epoxy resin>

YL983U (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 398, epoxy equivalent is 170g/eq

jER807 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 229, epoxy equivalent is 175 g/eq

<Bisphenol A (Ethylene Oxide (EO) Addition) Type Epoxy Resin>

BEO-60E (manufactured by Nippon Chemical Co., Ltd.): weight average molecular weight is 876, epoxy equivalent is 385 g/eq

<Aminophenol type epoxy resin>

jER630 (manufactured by Mitsubishi Chemical Corporation): weight average molecular weight is 124, epoxy equivalent is 97.5g/eq

EXA-835LV (Dainippon Ink and Chemicals, DIC): weight average molecular weight of 210, epoxy equivalent of 165 g/eq

Decane coupling agent (D)

KBM-403 (3-glycidoxypropyltrimethoxydecane molecular weight 236) (manufactured by Shin-Etsu Chemical Co., Ltd.)

Solvent (E)

MEK (methyl ethyl ketone)

<hardening accelerator>

FUJICURE 7000 (T & K TOKA), (imidazole liquid hardener)

2PZ-CNS-PW (manufactured by Shikoku Chemical Industry Co., Ltd.) (1-cyanoethyl-2-phenylimidazolium trimellitate)

2E4MZ (manufactured by Shikoku Chemical Industry Co., Ltd.) (2-ethyl-4-methylimidazole)

1,2-DMZ (1,2-dimethylimidazole)

1B2PZ (1-benzyl-2-phenylimidazole)

1BMI12 (1-isobutyl-2-methylimidazole)

<Other ingredients>

Zinc octoate 22% (manufactured by Dainippon Ink Chemical Industry Co., Ltd.) (zinc 2-ethylhexanoate, (C ₇ H ₁₅ COO) ₂ Zn)

[Example 1]

20 parts by mass of jER4005, 40 parts by mass of jER4010, and 40 parts by mass of jER630 were placed in a flask, and 200 parts by mass of methyl ethyl ketone was added thereto, followed by stirring and dissolving at room temperature. Into this solution, 3 parts by mass of the metal complex (B-1) and 1 part by mass of KBM-403 were added, and the mixture was stirred at room temperature to prepare a varnish of the epoxy resin composition.

Using a coater, on a substrate film (PET film G2 (manufactured by Teijin Dupont Films Co., Ltd.) having a thickness of 38 μm), The prepared varnish was applied by an applicator in such a manner that the thickness after drying was about 15 μm. The film was held in an inert oven (30 ° C) for 10 minutes, and then held in a vacuum oven (40 ° C) for 2 hours, and the MEK in the varnish coating film was removed by drying to form on the substrate film. A layer comprising a sheet of epoxy resin composition. Then, on the layer containing the sheet-like epoxy resin composition, a release-treated PET film (Purex A31 manufactured by DuPont Teijin Film Co., Ltd.) was thermocompression-bonded as a protective film to obtain a sheet for sealing. Moreover, the protective film is appropriately peeled off, and the surface of the layer containing the sheet-like epoxy resin composition is exposed and used.

[Example 2 to Example 7 and Comparative Example 1 to Comparative Example 6]

A varnish of an epoxy resin composition was prepared in the same manner as in Example 1 in the same manner as in Example 1 by coating and drying to obtain a sheet-like epoxy resin. A sheet for sealing the layer of the composition.

[Comparative Example 7]

(1) 40 parts by weight of EXA-835LV and 20 parts by weight of 2PZ-CNS-PW were uniformly dispersed and mixed using a three roll.

(2) 60 parts by weight of jER1256 and 200 parts by weight of MEK were placed in the flask, and stirred and dissolved at room temperature.

(3) The varnish of the epoxy resin composition was prepared by mixing (1) with (2) and 1 part by weight of KBM-403, and stirring at room temperature.

The prepared varnish was applied and dried in the same manner as in Example 1 to obtain a sheet for sealing having a layer containing a sheet-like epoxy resin composition.

The inclusions obtained in the examples and comparative examples were determined by the Karl Fischer method. The moisture content of the layer of the sheet-like epoxy resin composition was such that the water content of the layer containing the sheet-like epoxy resin composition of Examples 1 to 7 and Comparative Examples 1 to 6 was 0.1% by weight or less. The layer containing the sheet-like epoxy resin composition of Comparative Example 7 had a water content of 0.25% by weight.

Then, the transparency, the hardenability, and the melting point of the layer containing the sheet-like epoxy resin composition obtained in the examples and the comparative examples were evaluated by the following methods. The evaluation results are shown in Tables 2 and 3.

(1) Transparency (visual evaluation)

Using a varnish of the epoxy resin composition prepared in the examples or the comparative examples, a release film having a dry thickness of about 40 μm was applied on a release-treated PET film (Purex A53, 38 μm manufactured by DuPont Teijin Film Co., Ltd.). The coating was dried at 40 ° C for 2 hours under vacuum, and a solid-shaped layer containing a sheet-like epoxy resin composition was formed on the release-treated PET film at room temperature (about 25 ° C). Then, on the layer containing the sheet-like epoxy resin composition, a release-treated PET film (Purex A31 manufactured by DuPont Teijin Film Co., Ltd.) was thermocompression-bonded as a protective film to obtain a sheet for sealing.

The release-treated PET was peeled off from the obtained sheet for sealing, and a sheet-like epoxy resin composition was transferred onto a glass plate (S9213 manufactured by Loongson Glass, thickness: 1.2 mm, 76 mm × 52 mm). The sheet-like epoxy resin composition transferred onto the glass plate was heated in an oven at 100 ° C for 2 hours to form a cured product. The glass plate before the transfer is compared with the transparency of the glass plate in which the cured product of the sheet-like epoxy resin composition is laminated, and if the transparency is the same by visual observation, it is evaluated as ○, if the transparency is used When it is visually lowered, it is evaluated as ×.

(2) Transparency (light transmittance measurement)

The sheet for sealing produced in the same manner as the evaluation of the transparency of the above (1) was peeled off from the release-treated PET, and transferred on a glass plate (S9213 manufactured by Songlang Glass, thickness: 1.2 mm, 76 mm × 52 mm). A layer comprising a sheet of epoxy resin composition. The layer containing the sheet-like epoxy resin composition transferred onto the glass plate was heated in an oven at 100 ° C for 2 hours to obtain a cured product. The light transmittance of the sheet-like epoxy resin composition on the glass plate at a wavelength of 550 nm before and after curing was measured using an ultraviolet-visible spectrophotometer (Shimadzu Corporation UV-2550). Further, the light transmittance of the glass plate used when transferring the layer containing the sheet-like epoxy resin composition was taken as a baseline. When the light transmittance at a wavelength of 550 nm was 90% or more, it was evaluated as ○, and when it was less than 90%, it was evaluated as ×.

(3) Sturability

A varnish of the epoxy resin compositions obtained in the examples and the comparative examples was applied to the base film A53 (manufactured by DuPont Teijin Film Co., Ltd., thickness: 38 μm) so as to have a dry thickness of 15 μm by an applicator. The film was held in a inert oven (30 ° C) for 10 minutes. Then, it was kept in a vacuum oven (40 ° C) for 2 hours, and MEK in the varnish coating film was dried and removed, and a sheet for sealing having a layer containing a sheet-like epoxy resin composition formed on the substrate film was obtained.

Then, the layer containing the sheet-like epoxy resin composition of the sheet for sealing is thermocompression-bonded to a NaCl plate heated to about 45° C. on a hot plate, and after cooling to room temperature, the base film is peeled off, and the inclusion is included. The layer of the sheet-like epoxy resin composition was transferred to a NaCl plate. Coating additional NaCl on the transferred layer comprising the sheet-like epoxy resin composition The plate was used as a sample for IR absorption spectroscopy. At this time, as a spacer between two NaCl plates, an aluminum foil having a thickness of 11 μm was used.

As an IR absorption spectrum measuring apparatus, the IR absorption spectrum of the layer containing the sheet-like epoxy resin composition of the following three types was measured using the FT/IR-4100 by the Japan Seiko Co., Ltd., respectively.

(i) a sheet-like epoxy resin composition immediately after being sandwiched by a NaCl plate

(ii) a sheet-like epoxy resin composition after heating at 100 ° C for 2 hours in an oven

(iii) After the end, the sheet-like epoxy resin composition further heated in an oven at 150 ° C for 2 hours

Then, the hardenability (hardening rate) of the layer containing the sheet-like epoxy resin composition in the state of (ii) was calculated from the IR absorption spectrum of the above three states. In the calculation, the state of the above (i) was set to a curing rate of 0%, and the state of (iii) was set to a curing rate of 100%. Specifically, the hardening rate in the state of (ii) is calculated by the following procedure.

1) With the heat hardening reaction of the epoxy resin, the oxolane is reduced. Specific strength characteristics dioxolan Accordingly, respectively (i), (ii), (iii) , the computing the characteristic absorption of the benzene ring (about 1609cm ^-1) to internal standard absorption (about 910cm ^-1) of .

2) Then, the ratio of the amount of change in the specific strength from (i) to (ii) with respect to the amount of change in the specific strength from (i) to (iii) is calculated as the hardening rate in the state of (ii).

(4) Melting point

The sheet for sealing obtained in the examples or the comparative examples was dried, and cut into a strip having a length of about 40 mm and a width of about 5 mm to obtain a short strip test piece. After the layer containing the sheet-like epoxy resin composition of the test piece was adhered to a glass plate placed on a hot plate and heated, the test piece was slowly peeled off from the glass plate in a 180-degree direction. Starting from the set temperature of the heating plate at 35 ° C, the strip test piece was re-prepared for every 1 ° C set temperature, and the operation was repeated to maximize the adhesive peelability of the layer containing the sheet-like epoxy resin composition at the time of peeling. The temperature is taken as the melting point.

The melting point of the layer containing the sheet-like epoxy resin composition after storage for 7 days at 23 ° C and 60 RH% or after 14 days of storage was also measured in the same manner as above.

Regarding the hardenability of the layer containing the sheet-like epoxy resin composition, the larger the numerical values of Tables 2 and 3, the higher the curability. The melting point of the layer containing the sheet-like epoxy resin composition before hardening is less the change by storage, and it shows that the hardening by storage does not progress.

Comparing Examples 1 to 7 with Comparative Examples 1 to 7, it can be seen that in Examples 1 to 7, the layer containing the sheet-like epoxy resin composition has high hardenability immediately after production. In addition, even if it is stored at room temperature for 0 days to 14 days, the layer containing the sheet-like epoxy resin composition before the curing has little variation in the melting point, and therefore both the curability and the storage stability are excellent.

On the other hand, in Comparative Example 1 and Comparative Example 3 to Comparative Example 6, the layer containing the sheet-like epoxy resin composition had high hardenability immediately after production, but when it was stored at normal temperature, the melting point was greatly increased. The storage stability is lower than that of the embodiment. In addition, in Comparative Example 2 and Comparative Example 7, even if it was stored at normal temperature, the melting point did not change much, and therefore the storage stability was high, but the hardenability was low.

The present application claims priority based on Japanese Patent Application No. 2012-279261, filed on Dec. 21, 2012. The contents described in the specification and drawings of the application are all incorporated in the specification of the present application.

[Industrial availability]

The sheet-like epoxy resin composition of the present invention is excellent in hardenability and storage stability. Therefore, when the sheet-like epoxy resin composition of the present invention is used for, for example, sealing of an optical semiconductor, the production efficiency and the like of the optical semiconductor device can be improved.

10‧‧‧Seal film

12‧‧‧Base film

16‧‧‧layer containing a sheet of epoxy resin composition

18‧‧‧Protective film

Claims (17)

A sheet-like epoxy resin composition for surface sealing of an organic EL device, comprising: an epoxy resin (A) having two or more epoxy groups in one molecule and having a weight average molecular weight of 2 × 10 ³ ~1×10 ⁵ ; and a metal complex (B) containing one or more metal ions selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr; a tertiary amine which forms a complex and does not have an NH bond; and an anionic ligand selected from the group consisting of 2-ethylhexanoic acid, benzoic acid and acetamidine. The sheet-like epoxy resin composition for surface sealing of the organic EL device according to the first aspect of the invention, wherein the tertiary amine is any one of the following general formulae (1) to (6) Compound shown: (In the formula (1), R ₁ represents an aliphatic hydrocarbon group having 1 to 17 carbon atoms, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and R ₂ , R ₃ and R ₄ each independently represent a hydrogen group, An aliphatic hydrocarbon group having 1 to 17 carbon atoms, a hydroxyl group, an aryl group-containing group or a cyanoethyl group) (In the formula (2), RB1, RB3, RB4, and RB5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group, or a cyanoethyl group. ; RB2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and a plurality of groups selected from the group consisting of RB1, RB2, RB3, RB4, and RB5 may mutually Linking to form an alicyclic ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from oxygen, nitrogen, and sulfur) (In the formula (3), RC1, RC3, RC4 and RC5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. ; RC2 represents an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group; and a plurality of groups selected from RC1, RC2, RC3, RC4, and RC5 may mutually Linking to form an alicyclic ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from oxygen, nitrogen, and sulfur) (In the formula (4), RE1, RE2, RE3, RE4, and RE5 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyano group. Ethyl; a plurality of groups selected from the group consisting of RE1, RE2, RE3, RE4, and RE5 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a heterocyclic ring containing a hetero atom selected from oxygen, nitrogen, and sulfur) (In the formula (5), RF1, RF2, RF3, RF4, RF5, RF6, and RF7 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 and a hetero atom, a hydroxyl group, and an aryl group-containing group. a group or a cyanoethyl group; a plurality of groups selected from the group consisting of RF1, RF2, RF3, RF4, RF5, RF6, and RF7 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a compound selected from the group consisting of oxygen, nitrogen, and sulfur. Heteroatom of hetero atom) (In the formula (6), RG1, RG2, RG3, and RG4 each independently represent a hydrogen group, an aliphatic hydrocarbon group having a carbon number of 1 to 17 which may contain a hetero atom, a hydroxyl group, an aryl group-containing group or a cyanoethyl group. A plurality of groups selected from the group consisting of RG1, RG2, RG3, and RG4 may be bonded to each other to form an alicyclic ring, an aromatic ring, or a hetero ring containing a hetero atom selected from oxygen, nitrogen, and sulfur. A sheet-like epoxy resin composition for surface sealing of an organic EL device according to claim 1, which comprises: the above-mentioned sheet-like epoxy resin composition in CDCl ₃ at 25 ° C and 270 MHz chemical shifts in the ¹ H NMR chemical shift derived from a tertiary amine, a single peak is moved more than 0.05ppm and in CDCl ₃ at 25 ℃, the chemical shift of ¹ H NMR 270MHz with respect to the time of a tertiary amine. The sheet-like epoxy resin composition for surface sealing of the organic EL device according to the first aspect of the invention, wherein the tertiary amine has a molar ratio of 0.5 to 6.0 with respect to the metal ion. A sheet-like epoxy resin composition for surface sealing of an organic EL device according to claim 1, wherein the tertiary amine is selected from the group consisting of 1,8-diazabicyclo[5,4,0] Monocarb-7-ene, 1-methylimidazole, 1,2-dimethylimidazole, 1-benzyl-2-methylimidazole, 1-isobutyl-2-methylimidazole, 1-butylimidazole And at least one compound of the group consisting of 1,5-diazabicyclo[4,3,0]non-5-ene. A sheet-like epoxy resin composition for surface sealing of an organic EL device according to claim 1, wherein the above-mentioned sheet-like epoxy resin composition is in the above three stages. The above metal complex (B) is contained in the range of the equivalent functional ratio of the functional group/epoxy group of the amine of from 0.008 to 0.3. The sheet-like epoxy resin composition for surface sealing of the organic EL device according to the above aspect of the invention, wherein the content of the epoxy resin (A) is 55 mass with respect to the sheet-like epoxy resin composition. %~95% by mass. A sheet for sealing comprising a layer of a sheet-like epoxy resin composition for surface sealing of an organic EL element according to claim 1 of the patent application. The sheet for sealing according to the eighth aspect of the invention, wherein the layer of the sheet-like epoxy resin composition for surface sealing comprising the organic EL element has a light transmittance of 90 at a thickness of 40 μm and a wavelength of 550 nm. %the above. The sheet for sealing according to the invention of claim 8, wherein the protective sheet is further provided on at least one surface of the layer of the sheet-like epoxy resin composition for surface sealing of the organic EL element. The sheet for sealing according to claim 8, which is used for face sealing of an organic EL element. The sheet for sealing according to the invention of claim 8, wherein the layer containing the sheet-like epoxy resin composition for surface sealing of the organic EL element has a water content of 0.1% by mass or less. A method of producing an organic EL device, comprising: a step of preparing a substrate on which an organic EL element is formed; and a sheet-like epoxy resin composition for surface sealing comprising the organic EL element according to claim 1 of claim 1; a layer covering the above organic EL element; The organic EL device is surface-sealed by the cured product of the layer of the sheet-like epoxy resin composition for surface sealing of the organic EL device. An organic EL device comprising: an organic EL device; and a cured layer of a sheet-like epoxy resin composition for surface sealing of the organic EL device according to claim 1, which is in contact with the organic EL device And the above-mentioned organic EL element is surface-sealed. An organic EL device comprising: an organic EL device; and a cured layer of a sheet-like epoxy resin composition for surface sealing of the organic EL device according to claim 1, wherein the organic EL device is subjected to the organic EL device Surface sealing, in the spectrum measured by X-ray photoelectron spectroscopy (XPS), one or more metal atoms derived from a group selected from the group consisting of Zn, Bi, Ca, Al, Cd, La, and Zr are detected. a peak value and a peak derived from a nitrogen atom, wherein the detected molar ratio of the metal atom to the nitrogen atom is the metal atom: the nitrogen atom = 1:0.5 to 1:6.0, and the content of the metal atom is 0.5% by mass to 15% by mass. An organic EL display panel having the organic EL device as described in claim 14. An organic EL illumination having the organic EL device as described in claim 14 of the patent application.