JP2020053310A - Uv curable resin composition, manufacturing method of organic el element, and organic el element - Google Patents

Abstract

To provide a UV curable resin composition capable of preventing moisture from entering the organic EL element, which may be used for creating a sealing material to seal organic EL elements.SOLUTION: The UV curable resin composition contains an acrylic compound (A) and a light polymerization initiator (B). The acrylic compound (A) has a structure represented by the formula CH=CR-COO- (R-O)-CO-CR=CHand contains an acrylic compound (A1) of a boiling point of 270°C or higher. Each of Rand Ris hydrogen or a methyl group, n is an integer of 1 or more, and Ris an alkylene group having 3 or more carbon atoms. The percentage of the acrylic compound (A1) to the acrylic compound (A) is 50 mass% or more. The acrylic compound (A) does not include a compound having a boiling point of 260°C or lower, or the ratio of the compound having a boiling point of 260°C or lower in the acrylic compound (A) is 10 mass% or less.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an ultraviolet curable resin composition, a method for manufacturing an organic EL light emitting device, and an organic EL light emitting device. More specifically, the present invention relates to an ultraviolet curable resin composition for sealing an organic EL element, The present invention relates to a method for manufacturing an organic EL light-emitting device to be used, and an organic EL light-emitting device including the sealing material.

  Organic EL light-emitting devices are applied to lighting applications, display applications, and the like, and are expected to spread in the future.

  Among the organic EL light-emitting devices, a device called a top emission type has, for example, an organic EL element arranged on a support substrate, a transparent substrate arranged so as to face the support substrate, and a transparent substrate between the support substrate and the transparent substrate. It is configured by filling a suitable sealing material. In this case, light emitted from the organic EL element can be emitted outside through the sealing material and the transparent substrate.

  The sealing material suppresses the intrusion of moisture into the organic EL element, thereby suppressing the generation and growth of dark spots in the organic EL element. The dark spot is a portion that does not emit light and is generated when the organic EL element is deteriorated by moisture.

  The sealing material is made of a material containing an organic resin selected from, for example, an epoxy resin or an acrylic resin (see Patent Document 1). In particular, when an acrylic resin is used, the sealing material can be manufactured by curing the material by ultraviolet irradiation or the like, and thus the sealing material can be manufactured without applying a heat load to the organic EL element.

Japanese Patent No. 5581332

  Even when the organic EL element is covered with the encapsulant, there is a case where the penetration of moisture into the organic EL element cannot be sufficiently suppressed.

  An object of the present invention is to provide an ultraviolet curable resin composition which can be used for producing a sealing material for encapsulating an organic EL element and which can prevent moisture from penetrating into the organic EL element, and this ultraviolet curable resin composition And a method of manufacturing an organic EL light emitting device using the same, and an organic EL light emitting device provided with a sealing material made of a cured product of the ultraviolet curable resin composition.

The ultraviolet-curable resin composition according to one embodiment of the present invention is for sealing an organic EL, contains an acrylic compound (A) and a photopolymerization initiator (B), and the acrylic compound (A) has the following formula: An acrylic compound (A1) having a structure shown in (1) and having a boiling point of 270 ° C. or higher,
^{_{CH 2 = CR 1 -COO- (R}} 3 -O) n -CO-CR 2 = CH 2 ... (1)
In the formula (1), each of R ¹ and R ² is hydrogen or a methyl group, n is an integer of 1 or more, R ³ is an alkylene group having 3 or more carbon atoms, and when n is 2 or more, A plurality of R ³ may be the same or different from each other,
The percentage of the acrylic compound (A1) to the acrylic compound (A) is 50% by mass or more, and the acrylic compound (A) does not contain a compound having a boiling point of 260 ° C. or less, or has a boiling point in the acrylic compound (A). The proportion of the compound at 260 ° C. or lower is 10% by mass or lower.

  A method for manufacturing an organic EL light-emitting device according to one embodiment of the present invention is a method for manufacturing an organic EL light-emitting device including an organic EL element and a sealing material covering the organic EL element. Forming an encapsulant by molding an object by an inkjet method, and then irradiating the ultraviolet-curable resin composition with ultraviolet light to cure it.

  An organic EL light emitting device according to one embodiment of the present invention includes an organic EL element and a sealing material covering the organic EL element, and the sealing material is a cured product of the ultraviolet curable resin composition.

  One embodiment of the present invention has an advantage in that when it is used for manufacturing a sealing material for sealing an organic EL element, moisture does not easily enter the organic EL element.

1 is a schematic cross-sectional view illustrating a first example of an organic EL light emitting device according to an embodiment of the present invention. FIG. 4 is a schematic sectional view showing a second example of the organic EL light emitting device according to the embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described.

The ultraviolet curable resin composition for encapsulating an organic EL element (hereinafter, also referred to as composition (X)) according to the present embodiment contains an acrylic compound (A) and a photopolymerization initiator (B). The acrylic compound (A) has the structure represented by the following formula (1) and contains an acrylic compound (A1) having a boiling point of 270 ° C. or higher.
^{_{CH 2 = CR 1 -COO- (R}} 3 -O) n -CO-CR 2 = CH 2 ... (1)
In the formula (1), each of R ¹ and R ² is hydrogen or a methyl group, n is an integer of 1 or more, R ³ is an alkylene group having 3 or more carbon atoms, and when n is 2 or more, A plurality of R ³ may be the same or different.

  The percentage of the acrylic compound (A1) to the acrylic compound (A) is 50% by mass or more. The acrylic compound (A) does not contain a compound having a boiling point of 260 ° C. or less, or the proportion of the compound having a boiling point of 260 ° C. or less in the acrylic compound (A) is 10% by mass or less.

  From the composition (X), the sealing material 5 of the organic EL light emitting device 1 can be produced (see FIG. 1). Outgassing due to the acrylic compound (A1) hardly occurs from the sealing material 5. For this reason, it is possible to make it difficult to form a gap due to outgas in the organic EL light emitting device 1. Therefore, it is difficult for moisture to enter the organic EL element through the gap. Further, the acrylic compound (A1) does not easily increase the affinity of the sealing material 5 with water, so that it is difficult for moisture to enter the organic EL element through the sealing material 5. For this reason, it is difficult for moisture to enter the organic EL element.

  The glass transition temperature of the cured product of the composition (X) is preferably 80 ° C. or higher. That is, the composition (X) preferably has a property of being cured to have a glass transition temperature of 80 ° C. or higher when cured. In this case, the cured product can have good heat resistance. Therefore, for example, when a process involving an increase in temperature is performed on the cured product, the cured product is less likely to deteriorate. For this reason, for example, when the passivation layer 6 is formed by an evaporation method such as a plasma CVD method over the sealing material 5 made of the composition (X), the sealing material 5 is heated even if the sealing material 5 is heated. Hard to deteriorate. The glass transition temperature of the cured product is more preferably 90 ° C. or higher, and further preferably 100 ° C. or higher. The glass transition temperature of this cured product can be achieved by the composition of the composition (X) described in detail below.

  The viscosity at 25 ° C. of the composition (X) is preferably from 1 mPa · s to 30 mPa · s. In this case, the composition (X) can be easily molded at a room temperature by a method such as a casting method, and the composition (X) can also be molded by an inkjet method. The viscosity is more preferably 25 mPa · s or less, further preferably 20 mPa · s or less, and particularly preferably 15 mPa · s or less. It is also preferable that this viscosity is 5 mPa · s or more.

  It is also preferable that the viscosity at 40 ° C. of the composition (X) is from 1 mPa · s to 30 mPa · s. In this case, even if the viscosity of the composition (X) at room temperature is any value, it is possible to lower the viscosity by slightly heating the composition (X). Therefore, when heated, the composition (X) can be easily formed by a method such as a casting method, and the composition (X) can be formed by an ink jet method. Further, since the viscosity of the composition (X) can be reduced without greatly heating the composition (X), the composition of the composition (X) is less likely to change due to volatilization of components in the composition (X). The viscosity is more preferably 25 mPa · s or less, further preferably 20 mPa · s or less, and particularly preferably 15 mPa · s or less. It is also preferable that this viscosity is 5 mPa · s or more.

The viscosity of the composition (X) is measured using a rheometer at a shear rate of 100 s ^-1 . As the rheometer, for example, model number DHR-2 manufactured by Anton Paar Japan can be used.

  Such a low viscosity at 25 ° C. or 40 ° C. of the composition (X) can be achieved by the composition of the composition (X) described in detail below.

  When the thickness of the cured product of the composition (X) is 10 μm, the total light transmittance is preferably 90% or more. In this case, when the cured product is applied to the sealing material 5 in the organic EL light emitting device 1, the extraction efficiency of light that passes through the sealing material 5 and is emitted to the outside can be particularly improved. The light transmittance of such a cured product can also be achieved by the composition of the composition (X) described in detail below.

  Hereinafter, the present embodiment will be described in more detail.

1. First, the structure of the organic EL light emitting device will be described. The organic EL light emitting device 1 includes an organic EL element 4 and a sealing material 5 that covers the organic EL element 4. The sealing material 5 may cover the organic EL element 4 in a state of being in direct contact with the organic EL element 4, or may be configured to cover the organic EL element 4 with any layer interposed between the sealing material 5 and the organic EL element 4. May be covered. Note that EL is an abbreviation for electroluminescence. Further, the organic EL element 4 is also called an organic light emitting diode.

  A first example of the structure of the organic EL light emitting device 1 will be described with reference to FIG. This organic EL light emitting device 1 is a top emission type. The organic EL light emitting device 1 includes a support substrate 2, a transparent substrate 3 facing the support substrate 2 at an interval, an organic EL element 4 on a surface of the support substrate 2 facing the transparent substrate 3, and the support substrate 2. A sealing material 5 is provided between the transparent substrate 3 and the transparent substrate 3. In the first example, the organic EL light emitting device 1 includes a passivation layer 6 that covers the surface of the support substrate 2 facing the transparent substrate 3 and the organic EL element 4. That is, the passivation layer 6 is interposed between the organic EL element 4 and the sealing material 5 covering the organic EL element 4.

  The support substrate 2 is made of, for example, a resin material, but is not limited to this. The transparent substrate 3 is made of a light-transmitting material. The transparent substrate 3 is, for example, a glass substrate or a transparent resin substrate. The organic EL element 4 includes, for example, a pair of electrodes and an organic light emitting layer between the electrodes. The organic light emitting layer includes, for example, a hole injection layer, a hole transport layer, an organic light emitting layer, and an electron transport layer, and these layers are stacked in the order described above. Although only one organic EL element 4 is shown in FIG. 1, the organic EL light emitting device 1 includes a plurality of organic EL elements 4, and the plurality of organic EL elements 4 form an array on the support substrate 2. It may be configured. The passivation layer 6 is preferably made of silicon nitride or silicon oxide.

  A second example of the structure of the organic EL light emitting device 1 will be described with reference to FIG. Elements common to those in the first example shown in FIG. 1 are denoted by the same reference numerals as in FIG. 1, and detailed description will be omitted as appropriate. The organic EL light emitting device 1 shown in FIG. 2 is also a top emission type. The organic EL light emitting device 1 includes a support substrate 2, a transparent substrate 3 facing the support substrate 2 at an interval, an organic EL element 4 on a surface of the support substrate 2 facing the transparent substrate 3, and an organic EL element 4. Is provided.

  As in the case of the first example, the organic EL element 4 includes, for example, a pair of electrodes 41 and 43 and an organic light emitting layer 42 between the electrodes 41 and 43. The organic light emitting layer 42 includes, for example, a hole injecting layer 421, a hole transporting layer 422, an organic light emitting layer 423, and an electron transporting layer 424, and these layers are stacked in the order described above.

  The organic EL device 1 includes a plurality of organic EL elements 4, and the plurality of organic EL elements 4 form an array 9 (hereinafter, referred to as an element array 9) on the support substrate 2. The element array 9 also includes the partition wall 7. The partition 7 is on the support substrate 2 and partitions between two adjacent organic EL elements 4. The partition 7 is produced by, for example, molding a photosensitive resin material by a photolithography method. The element array 9 also includes connection wirings 8 for electrically connecting the electrodes 43 and the electron transport layers 424 of the adjacent organic EL elements 4. The connection wiring 8 is provided on the partition wall 7.

  The organic EL light emitting device 1 also includes a passivation layer 6 that covers the organic EL element 4. The passivation layer 6 is preferably made of silicon nitride or silicon oxide. Passivation layer 6 includes a first passivation layer 61 and a second passivation layer 62. The first passivation layer 61 covers the organic EL element 4 by covering the element array 9 in a state of being in direct contact with the element array 9. The second passivation layer 62 is disposed at a position opposite to the element array 9 with respect to the first passivation layer 61, and a space is provided between the second passivation layer 62 and the first passivation layer 61. ing. The sealing material 5 is filled between the first passivation layer 61 and the second passivation layer 62. That is, the first passivation layer 61 is interposed between the organic EL element 4 and the sealing material 5 covering the organic EL element 4.

  Further, a second sealing material 52 is filled between the second passivation layer 62 and the transparent substrate 3. The second sealing material 52 is made of, for example, a transparent resin material. The material of the second sealing material 52 is not particularly limited. The material of the second sealing material 52 may be the same as or different from that of the sealing material 5.

  The sealing material 5 in the organic EL light emitting device 1 having the structure exemplified above can be made from the ultraviolet curable resin composition according to the present embodiment. That is, the ultraviolet curable resin composition is used for producing the sealing material 5 for the organic EL element 4. In other words, the ultraviolet curable resin composition is preferably a composition for producing a sealing material, a composition for sealing an organic EL element, or a composition for producing an organic EL light emitting device.

2. UV-curable resin composition The UV-curable resin composition (hereinafter, also referred to as composition (X)) according to the present embodiment will be described.

  As described above, the composition (X) contains the acrylic compound (A) and the photopolymerization initiator (B). When the composition (X) is irradiated with ultraviolet rays, a photoradical polymerization reaction is initiated by the photopolymerization initiator (B) to cure the acrylic compound (A), whereby a cured product can be produced. The components of the composition (X) are described in more detail below.

  As described above, the composition (X) contains the acrylic compound (A). The acrylic compound (A) has one or more (meth) acryloyl groups in one molecule. It should be noted that “(meth) acryl” is at least one of “acryl” and “methacryl”.

  The viscosity at 25 ° C. of the entire acrylic compound (A) is preferably 50 mPa · s or less. In this case, the acrylic compound (A) can make the composition (X) particularly low in viscosity. The viscosity of the entire acrylic compound (A) is more preferably 30 mPa · s or less, further preferably 25 mPa · s or less, and particularly preferably 20 mPa · s or less. Further, the viscosity of the entire acrylic compound (A) is, for example, 3 mPa · s or more.

  It is also preferable that the viscosity at 40 ° C. of the entire acrylic compound (A) is 50 mPa · s or less. In this case, the acrylic compound (A) can particularly lower the viscosity of the composition (X) when heated. The viscosity of the entire acrylic compound (A) is more preferably 30 mPa · s or less, more preferably 25 mPa · s or less, and particularly preferably 20 mPa · s or less. The viscosity of the entire acrylic compound (A) is, for example, 3 mPa · s or more.

  The compound which the acrylic compound (A) may contain will be described.

  As described above, the acrylic compound (A) has the structure represented by the formula (1) and contains the acrylic compound (A1) having a boiling point of 270 ° C. or higher. In other words, the acrylic compound (A) contains the acrylic compound (A1), and the acrylic compound (A1) is at least a compound having a boiling point of 270 ° C. or higher in the group consisting of compounds having a structure represented by the formula (1). Consists of only one compound.

  Since the boiling point of the acrylic compound (A1) is 270 ° C. or higher, the acrylic compound (A1) volatilizes from the composition (X) during storage of the composition (X) and when the composition (X) is heated. Hateful. Therefore, the storage stability of the composition (X) is not easily impaired. Further, even if the acrylic compound (A1) remains unreacted in the cured product of the composition (X) and the sealing material 5, outgas due to the acrylic compound (A1) from the cured product and the sealing material 5 Is unlikely to occur. For this reason, voids due to outgas hardly occur in the organic EL light emitting device 1. If there is a gap in the organic EL light emitting device 1, moisture may reach the organic EL element 4 through the gap. However, if there is little gap, moisture does not easily reach the organic EL element 4. 4 is hardly deteriorated by moisture. The boiling point is a boiling point under normal pressure obtained by converting the boiling point under reduced pressure, and can be determined, for example, by the method shown in Science of Petroleum, Vol. II. P.1281 (1938). More preferably, the boiling point of the acrylic compound (A1) is 280 ° C. or higher.

Further, since the acrylic compound (A1) has a structure represented by the formula (1), and particularly, the carbon number of R ^{3 in} the formula (1) is 3 or more, the acrylic compound (A1) It is difficult to increase the affinity with water. For this reason, it is difficult for moisture to enter the organic EL element through the sealing material 5. The carbon number of R ³ is, for example, 3 or more and 15 or less. Further, the acrylic compound (A1) has a structure represented by the formula (1), and particularly has two (meth) acryloyl groups in one molecule, so that the glass transition temperature of the cured product can be increased. Therefore, the heat resistance of the cured product and the sealing material 5 can be increased. Further, n in the formula (1) is, for example, an integer of 1 or more and 12 or less.

  The percentage of the acrylic compound (A1) to the acrylic compound (A) is 50% by mass or more. Therefore, the storage stability of the composition (X) is effectively enhanced, the generation of outgas from the sealing material 5 is effectively reduced, and the affinity of the sealing material 5 for water is not particularly increased. . Further, the percentage of the acrylic compound (A1) to the acrylic compound (A) is, for example, 100% by mass or less, or 95% by mass or less, and preferably 80% by mass or less.

  The viscosity at 25 ° C. of the acrylic compound (A1) is preferably 25 mPa · s or less. In this case, the acrylic compound (A1) can lower the viscosity of the composition (X). The viscosity at 25 ° C. of the acrylic compound (A1) is more preferably 25 mPa · s or less, further preferably 20 mPa · s or less, and particularly preferably 15 mPa · s or less. The viscosity of the acrylic compound (A1) at 25 ° C. is, for example, 1 mPa · s or more, preferably 3 mPa · s or more, more preferably 5 mPa · s or more.

  The acrylic compound (A1) comprises, for example, di (meth) acrylate of alkylene glycol, di (meth) acrylate of polyalkylene glycol, and di (meth) acrylate of alkylene oxide-modified alkylene glycol. It contains at least one compound selected from the group.

The di (meth) acrylate of alkylene glycol is a compound in which n is 1 in the formula (1). In this case, the carbon number of R ³ in the formula (1) is preferably 4 to 12. R ³ may be linear or branched. Particularly, di (meth) acrylate of alkylene glycol is 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, 1,9- Nonanediol diacrylate, 1,10-decanediol diacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9 It preferably contains at least one compound selected from the group consisting of -nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, and 1,12-dodecanediol dimethacrylate. In addition, di (meth) acrylic acid esters of alkylene glycols are available from Sartomer Co., Ltd., product number SR213, Osaka Organic Chemical Industry Co., Ltd. product number SR195, Sartomer Co., Ltd. product number SR212, Sartomer Co., Ltd. product number SR247, Kyoei Chemical Co., Ltd. Light Acrylate NP-A, Sartomer's part number SR238NS, Osaka Organic Chemical Industry's part number V230, Daicel's part number HDDA, Kyoei Chemical Industry's part number 1,6HX-A, Osaka Organic Chemical Industry V260, Kyoei Chemical Industry Co., Ltd., 1,9-ND-A, Shin Nakamura Chemical Co., Ltd. product number A-NOD-A, Sartomer Co., Ltd. product number CD595, Sartomer Co., Ltd. product number SR214NS, Shin Nakamura Part number BD manufactured by Chemical Industry, part number SR297 manufactured by Sartomer, part number SR248 manufactured by Sartomer, Kyoei Chemical Trade name light ester NP, Sartomer product number SR239NS, Kyoei Chemical Co. product name light ester 1,6HX, Shinnakamura Chemical Co., product number HD-N, Kyoei Chemical Co. product name light ester It consists of 1,9ND, product number NOD-N manufactured by Shin-Nakamura Chemical Co., Ltd., product name light ester 1,10DC manufactured by Kyoei Chemical Industry Co., Ltd., product number DOD-N manufactured by Shin-Nakamura Chemical Co., Ltd., and product number SR262 manufactured by Sartomer. It preferably contains at least one compound selected from the group.

The di (meth) acrylate of polyalkylene glycol is a compound in which n is 2 or more in the formula (1). n is, for example, 2 to 10, preferably 2 to 7, more preferably 2 to 6, and also preferably 2 to 3. R ³ has, for example, 2 to 5 carbon atoms. The greater the number of carbon atoms, the higher the hydrophobicity of the cured product and the sealing material 5, and the more difficult it is for the sealing material 5 to transmit moisture. The di (meth) acrylates of polyalkylene glycols are especially diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, hexaethylene glycol dimethacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate. It is preferable to contain at least one compound selected from the group consisting of acrylate, tripropylene glycol dimethacrylate and tritetramethylene glycol diacrylate. The di (meth) acrylic acid esters of polyalkylene glycols are, in particular, part number SR230 manufactured by Sartomer, part number SR508NS manufactured by Sartomer, part number DPGDA manufactured by Daicel, part number SR306NS manufactured by Sartomer, and part number TPGDA manufactured by Daicel. Product number V310HP manufactured by Osaka Organic Chemical Industry Co., Ltd., product number APG200 manufactured by Shin-Nakamura Chemical Co., Ltd., product name light acrylate PTMGA-250 manufactured by Kyoei Chemical Industry Co., Ltd., product number SR231NS manufactured by Sartomer, product name light manufactured by Kyoei Chemical Industry Co., Ltd. Ester 2EG, Sartomer product number SR205NS, Kyoei Chemicals Co., Ltd. product light ester 3EG, Sartomer product number SR210NS, Kyoei Chemicals product name Light Ester 4EG, Mitsubishi Chemical product name Acryester HX and new Nakamura Chemical Preferably contains at least one compound selected from the group consisting of Gosha made part 3PG.

  The di (meth) acrylate of alkylene oxide-modified alkylene glycol contains, for example, propylene oxide-modified neopentyl glycol. The di (meth) acrylate of alkylene oxide-modified alkylene glycol contains, for example, product number EBECRYL145 manufactured by Daicel Corporation.

  The percentage of the component having a boiling point of 270 ° C. or higher in the acrylic compound (A) is preferably 80% by mass or more. When the acrylic compound (A) further contains a compound other than the acrylic compound (A1), in the acrylic compound (A), in all components including the acrylic compound (A) and the compound other than the acrylic compound (A1), Preferably, the percentage of components having a boiling point of 270 ° C. or higher is 80% by mass or more. In this case, the storage stability of the composition (X) is not particularly impaired, and outgassing from the cured product and the sealing material 5 is particularly unlikely to occur. More preferably, the percentage of the component having a boiling point of 280 ° C. or more in the acrylic compound (A) is 80% by mass or more.

  Compounds other than the acrylic compound (A1) that the acrylic compound (A) may contain will be described.

  The acrylic compound (A) may further contain a polyfunctional acrylic compound (A2) other than the acrylic compound (A1). The polyfunctional acrylic compound (A2) can increase the glass transition temperature of the cured product, and therefore can enhance the heat resistance of the cured product and the sealing material 5. The polyfunctional acrylic compound (A2) contains, for example, polyethylene glycol di (meth) acrylate.

  The polyfunctional acrylic compound (A2) preferably contains a compound (A21) having three or more (meth) acryloyl groups in one molecule. That is, the acrylic compound (A) preferably contains the compound (A21). In this case, the compound (A21) can contain, for example, at least one selected from the group consisting of trimethylolpropane triacrylate and trimethylolpropane trimethacrylate. When the acrylic compound (A) contains the compound (A21), the compound (A21) can particularly increase the glass transition temperature of the cured product, and therefore, particularly enhances the heat resistance of the cured product and the sealing material 5. Can be.

  When the acrylic compound (A) contains the compound (A21), the percentage of the compound (A21) to the acrylic compound (A) is preferably more than 0% by mass and 25% by mass or less. More preferably, the percentage of the component (A3) is 10% by mass or more. In this case, the glass transition temperature of the cured product can be particularly increased. When the content of the compound (A21) is 25% by mass or less, the viscosity of the composition (X) due to the compound (A21) does not easily increase. When the percentage of the compound (A21) is at most 20% by mass, the viscosity of the composition (X) will not particularly increase.

  The acrylic compound (A) may further contain a monofunctional acrylic compound (A3) having only one (meth) acryloyl group in one molecule. The monofunctional acrylic compound (A3) can suppress shrinkage of the composition (X) during curing. Further, the monofunctional acrylic compound (A3) can contribute to a reduction in the viscosity of the composition (X). When the acrylic compound (A) contains the monofunctional acrylic compound (A3), the percentage of the monofunctional acrylic compound (A3) to the total amount of the acrylic compound (A) is preferably more than 0% by mass and 70% by mass or less. . When the percentage of the monofunctional acrylic compound (A3) is more than 0% by mass, shrinkage of the composition (X) during curing can be suppressed by the monofunctional acrylic compound (A3). More preferably, the percentage of the monofunctional acrylic compound (A3) is 5% by mass or more. When the percentage of the monofunctional acrylic compound (A3) is 70% by mass or less, outgas due to the monofunctional acrylic compound (A3) hardly occurs from the composition (X) and the cured product. Further, when the amount of the monofunctional acrylic compound (A3) is 70% by mass or less, the amount of the polyfunctional component in the acrylic compound (A) can be ensured, so that the cured product and the encapsulant 5 Can be particularly improved in heat resistance. The monofunctional acrylic compound (A3) preferably has a percentage of 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less.

  Monofunctional acrylic compounds (A3) include, for example, isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate, 4-tert-butylcyclohexyl (meth) Acrylate, dicyclopentenyloxyethyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl ( (Meth) acrylate, isooctyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, methoxytriethylene glycol (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate Relate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxydixylethyl (meth) acrylate, ethyldiglycol (meth) acrylate, cyclic trimethylolpropane formalmono (meth) acrylate Imide (meth) acrylate, isoamyl (meth) acrylate, ethoxylated succinic acid (meth) acrylate, trifluoroethyl (meth) acrylate, ω-carboxypolycaprolactone mono (meth) acrylate, cyclohexyl (meth) acrylate, 2- ( 2-ethoxyethoxy) ethyl (meth) acrylate, stearyl (meth) acrylate, diethylene glycol monobutyl ether (meth) acrylate, lauri (Meth) acrylate, isodecyl (meth) acrylate, isooctyl (meth) acrylate, octyl / decyl (meth) acrylate, tridecyl (meth) acrylate, caprolactone (meth) acrylate, ethoxylated (4) nonylphenol (meth) acrylate, methoxy Polyethylene glycol (350) mono (meth) acrylate, methoxy polyethylene glycol (550) mono (meth) acrylate, phenoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tetrahydrofurfuryl (meth) ) Acrylate, benzyl (meth) acrylate, methylphenoxyethyl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate , Tribromophenyl (meth) acrylate, ethoxylated tribromophenyl (meth) acrylate, 2-phenoxyethyl (meth) acrylate, ethylene oxide adduct of 2-phenoxyethyl (meth) acrylate, 2-phenoxyethyl (meth) Propylene oxide adduct of acrylate, phenoxydiethylene glycol (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 3-methacryloyloxymethylcyclohexene oxide, and 3- (meth) acryloyloxymethylcyclohexene oxide Contains at least one compound selected.

  The monofunctional acrylic compound (A3) preferably contains a compound having an alicyclic structure. Compounds having an alicyclic structure include, for example, cyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, caprolactone-modified tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, It contains at least one compound selected from the group consisting of cyclopentenyloxyethyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate and 4-tert-butylcyclohexyl (meth) acrylate.

  It is also preferable that the monofunctional acrylic compound (A3) contains a compound (A31) represented by the following formula (10). In this case, the viscosity of the composition (X) is easily reduced, and adhesion to a member made of an inorganic material such as the passivation layer 6 is easily imparted to the sealing material 5 made of the composition (X). In addition, the compound (A31) has a property of hardly volatilizing though having a low viscosity. Therefore, even when the composition (X) is stored, the composition (X) is less likely to change in composition due to volatilization of the monofunctional acrylic compound (A3).

In the formula (10), R ⁰ is H or a methyl group. X is a single bond or a divalent hydrocarbon group. Each of the R ¹ R ¹¹ is H, alkyl or -R ¹² -OH, R ¹² is at least one of R ¹¹ from it and R ¹ is an alkylene group which is an alkyl group or -R ¹² -OH. R ¹ to R ¹¹ are not chemically bonded to each other.

  When X is a divalent hydrocarbon group, X preferably has 1 to 5 carbon atoms, and more preferably 1 to 3 carbon atoms. The divalent hydrocarbon group is, for example, a methylene group, an ethylene group or a propylene group. It is particularly preferable that X is a single bond or a methylene group. In this case, there is an advantage that the compound (A31) has a small molecular weight and a low viscosity.

When at least one of R ¹ to R ¹¹ is an alkyl group, the alkyl group preferably has 1 to 8 carbon atoms. The alkyl group is, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group or an octyl group. The alkyl group may be linear or branched. That is, for example, when the alkyl group is a butyl group, the butyl group may be a t-butyl group, an n-butyl group, or a sec-butyl group. When the alkyl group is a hexyl group, the hexyl group may be a t-hexyl group, an n-hexyl group, or a sec-hexyl group. When the alkyl group is an octyl group, the octyl group may be, for example, a t-octyl group. It is particularly preferred if the alkyl group is a methyl group or a t-butyl group. In this case, there is an advantage that the compound (A31) has a small molecular weight and a low viscosity.

In the formula (10), it is preferable that an alkyl group or —R ¹² —OH is connected to only the 4-position of the cyclohexane ring. That is, among R ¹ to R ¹¹ , it is preferable that at least one of R ⁶ and R ⁷ is an alkyl group or —R ¹² —OH, and the rest are each H. It is particularly preferred that, of R ¹ to R ¹¹ , only R ⁶ is an alkyl group or —R ¹² —OH, and the rest are each H. In this case, the compound represented by the formula (10) can have good reactivity, and particularly easily gives the sealing material 5 adhesion to a member made of an inorganic material. This is because that has a conformation of the cyclohexane ring is boat-shaped in the compound represented by the formula (10), and bulky alkyl group or -R ¹² -OH at the 4-position is easily located pseudo equatorial position it is conceivable that. It is considered that when the compound represented by the formula (10) has such a structure, the reactivity of the (meth) acryloyl group in the compound represented by the formula (10) is increased. When the compound represented by the formula (10) has such a structure, the compound represented by the formula (10) can increase the free volume in the sealing material 5. Therefore, it is considered that the interface free energy between the sealing material 5 and the member made of the inorganic material tends to be small, and therefore, the adhesion between the sealing material 5 and the member made of the inorganic material tends to be high. The higher the bulk alkyl group or -R ¹² -OH, alkyl or -R ¹² -OH is likely located in pseudo equatorial position. From this point of view, it is preferable that preferably larger the number of carbon atoms in the alkyl group or -R ¹² -OH, also an alkyl group or -R ¹² -OH and a branch. For example it is preferable alkyl group or -R ¹² -OH is a t- butyl group.

In the formula (10), it is also preferable that an alkyl group or —R ¹² —OH is connected only to each of the 3- and 5-positions of the cyclohexane ring. That is, among R ¹ to R ¹¹ , at least one of R ⁴ and R ⁵ is an alkyl group or —R ¹² —OH, and at least one of R ⁸ and R ⁹ is an alkyl group or —R ¹² —OH, It is preferred that each of the remaining is H. From R ¹ of R ^11, only one of R ⁴ and R ⁵ is an alkyl or -R ¹² -OH, at least one of R ⁸ and R ⁹ is an alkyl or -R ¹² -OH, the remaining More preferably, each is H. Of R ¹ to R ¹¹ , at least one of R ⁴ and R ⁵ is an alkyl group or —R ¹² —OH, only one of R ⁸ and R ⁹ is an alkyl group or —R ¹² —OH, and the remaining More preferably, each is H. Also in this case, the compound represented by the formula (10) can have good reactivity, and particularly easily gives the sealing material 5 adhesion to a member made of an inorganic material. This is cyclohexane ring in the compound represented by the formula (10) has a conformation of a boat-type, and 3- and 5-position bulky alkyl group or -R ¹² -OH in each are located in pseudo equatorial position It is thought that it is easy. For this, as in the case where only the 4-position of the cyclohexane ring is an alkyl group or -R ¹² -OH connected, reactive (meth) acryloyl group in the compound represented by the formula (10) is increased, and It is considered that the adhesion between the sealing material 5 and the member made of the inorganic material is likely to be high. The higher the bulk alkyl group or -R ¹² -OH, alkyl or -R ¹² -OH is likely located in pseudo equatorial position. From this point of view, it is preferable that preferably larger the number of carbon atoms in the alkyl group or -R ¹² -OH, also an alkyl group or -R ¹² -OH and a branch. For example it is preferable alkyl group or -R ¹² -OH is a t- butyl group.

When at least one of R ¹ to R ¹¹ is —R ¹² —OH, the carbon number of R ¹² is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. R ¹² is, for example, a methylene group, an ethylene group or a propylene group. It is particularly preferred if R ¹² is a methylene group. In this case, there is an advantage that the compound (A31) has a small molecular weight and a low viscosity.

In the formula (10), it is particularly preferable that each of R ¹ to R ¹¹ is H or an alkyl group and at least one of R ¹ to R ¹¹ is an alkyl group. In this case, the compound represented by the formula (10) can have a particularly low viscosity, so that the composition (X) can have a particularly low viscosity. Therefore, the composition (X) is particularly easily formed by the ink jet method.

  The compound (A31) preferably contains at least one compound selected from the group consisting of a compound represented by the following formula (11), a compound represented by the following formula (12), and a compound represented by the following formula (13).

  It is particularly preferable that the monofunctional acrylic compound (A3) contains at least one of the compound represented by the formula (11) and the compound represented by the formula (12). In this case, the viscosity of the composition (X) is particularly easily reduced, the glass transition temperature of the sealing material 5 is particularly easily increased, and the adhesion between the sealing material 5 and a member made of an inorganic material is particularly easily increased. Further, since the compound represented by the formula (11) and the compound represented by the formula (12) are hard to volatilize, the storage stability of the composition (X) is easily improved.

  The monofunctional acrylic compound (A3) also preferably contains a compound having a cyclic ether structure. The number of ring members of the cyclic ether structure in the compound having a cyclic ether structure is preferably 3 or more, more preferably 3 or more and 4 or less. The number of carbon atoms contained in the cyclic ether structure is preferably 2 or more and 9 or less, more preferably 2 or more and 6 or less. The compound having a cyclic ether structure contains, for example, at least one compound selected from the group consisting of 3-methacryloyloxymethylcyclohexene oxide and 3-acryloyloxymethylcyclohexene oxide.

  The monofunctional acrylic compound (A3) preferably contains at least one compound having a viscosity at 25 ° C. of 20 mPa · s or less. In this case, the viscosity of the composition (X) can be reduced.

  The monofunctional acrylic compound (A3) preferably contains at least one compound having a glass transition temperature of 80 ° C or higher. In this case, the cured product of the composition (X) may have a high glass transition temperature. The monofunctional acrylic compound (A3) more preferably contains at least one compound having a glass transition temperature of 90 ° C. or more, and more preferably contains at least one compound having a glass transition temperature of 100 ° C. or more.

  The monofunctional acrylic compound (A3) preferably contains at least one compound having a boiling point of 200 ° C. or higher. In this case, the monofunctional acrylic compound (A3) hardly lowers the storage stability of the composition (X). It is more preferable that the monofunctional acrylic compound (A3) contains at least one compound having a boiling point of 250 ° C. or higher.

  It is particularly preferable that the monofunctional acrylic compound (A3) contains at least one compound having a viscosity at 25 ° C. of 20 mPa · s or less and a glass transition temperature of 80 ° C. or more. It is also preferable that the monofunctional acrylic compound (A3) contains at least one compound having a viscosity at 25 ° C of 20 mPa · s or less and a boiling point of 200 ° C or more. It is also preferable that the monofunctional acrylic compound (A3) contains at least one compound having a glass transition temperature of 80 ° C or higher and a boiling point of 200 ° C or higher. If the monofunctional acrylic compound (A3) contains at least one compound having a viscosity at 25 ° C. of 20 mPa · s or less, a glass transition temperature of 80 ° C. or more, and a boiling point of 200 ° C. or more, Particularly preferred.

  Particularly, the monofunctional acrylic compound (A3) includes isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate and 4-tert-butylcyclohexyl (meth) acrylate It is preferable to contain at least one compound selected from the group consisting of Isobornyl (meth) acrylate, dicyclopentanyl (meth) acrylate, 3,3,5-trimethylcyclohexyl (meth) acrylate and 4-tert-butylcyclohexyl (meth) acrylate have high glass transition temperatures, low viscosities and Since it has a high boiling point, the properties of the composition (X), the curing agent, and the sealing material 5 can be particularly enhanced.

  The acrylic compound (A) is selected from the group consisting of a compound (A41) having silicon in the molecular skeleton, a compound (A42) having phosphorus in the molecular skeleton, and a compound (A43) having nitrogen in the molecular skeleton. It is preferable to further contain at least one compound. In this case, the adhesion between the cured product and the sealing material 5 and the member made of the inorganic material is improved. For this reason, a gap is hardly generated between the sealing material 5 and the passivation layer 6, and it is difficult for moisture to enter the organic EL element 4 through the gap.

  Note that the compound (A41), the compound (A42) and the compound (A43) are defined by the types of atoms in the molecular skeleton. Therefore, the compound included in each of the polyfunctional acrylic compound (A2) and the monofunctional acrylic compound (A3) overlaps with the compound included in each of the compound (A41), the compound (A42), and the compound (A43). sell.

  The compound (A41) is, for example, 3- (trimethoxysilyl) propyl acrylate (for example, product number KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd.) and a (meth) acryl group-containing alkoxysilane oligomer (for example, product number KR-513 manufactured by Shin-Etsu Chemical Co., Ltd.) )) And at least one compound selected from the group consisting of: However, since the boiling point of 3- (trimethoxysilyl) propyl acrylate is 260 ° C., when the acrylic compound (A) contains 3- (trimethoxysilyl) propyl acrylate, the acrylic acid to the acrylic compound (A) is used. The percentage of 3- (trimethoxysilyl) propyl must be less than 10% by weight.

  Compound (A42) includes, for example, acid phosphooxy (meth) acrylate such as acid phosphooxypolyoxypropylene glycol monomethacrylate.

  The compound (A43) includes, for example, at least one compound selected from the group consisting of acryloylmorpholine, diethylacrylamide, dimethylaminopropylacrylamide, and pentamethylpiperidyl methacrylate.

  When the acrylic compound (A) contains at least one compound selected from the group consisting of the compound (A41), the compound (A42) and the compound (A43), the compound (A41) and the compound (A42) with respect to the acrylic compound (A) ) And the compound (A43) are preferably at least 0.5% by mass and at most 20% by mass, more preferably at least 1% by mass and at most 15% by mass.

  The composition (X) may further contain a radical polymerizable compound (E) other than the acrylic compound (A). The radical polymerizable compound (E) includes a polyfunctional radical polymerizable compound (E1) having two or more radical polymerizable functional groups in one molecule and a monofunctional compound having only one radical polymerizable functional group in one molecule. Any one or both of the radically polymerizable compound (E2) can be contained. The amount of the radical polymerizable compound (E) based on the total amount of the acrylic compound (A) and the radical polymerizable compound (E) is, for example, 10% by mass or less. The polyfunctional radical polymerizable compound (E1) is, for example, a group consisting of an aromatic urethane oligomer, an aliphatic urethane oligomer, an epoxy acrylate oligomer, a polyester acrylate oligomer and other special oligomers having two or more ethylenic double bonds in one molecule. And at least one compound selected from the group consisting of: The monofunctional radically polymerizable compound (E2) includes, for example, N-vinylformamide, vinylcaprolactam, vinylpyrrolidone, phenylglycidyl ether, p-tert-butylphenylglycidylether, butylglycidylether, 2-ethylhexylglycidylether, allylglycidylether, 1,2-butylene oxide, 1,3-butadiene monoxide, 1,2-epoxide decane, epichlorohydrin, 1,2-epoxydecane, styrene oxide, cyclohexene oxide, 3-vinylcyclohexene oxide, 4-vinylcyclohexene It contains at least one compound selected from the group consisting of oxide, N-vinylpyrrolidone and N-vinylcaprolactam.

  The photopolymerization initiator (B) is not particularly limited as long as it is a compound that generates a radical species when irradiated with ultraviolet rays. Examples of the photopolymerization initiator (B) include aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazole compounds , A ketoxime ester compound, a borate compound, an azinium compound, a metallocene compound, an active ester compound, a compound having a carbon-halogen bond, and an alkylamine compound. The amount of the photopolymerization initiator (B) is, for example, 1 part by weight or more and 10 parts by weight or less based on 100 parts by weight of the composition (X).

  The photopolymerization initiator (B) may contain a sensitizer as a part of the photopolymerization initiator (B). The sensitizer can promote the radical generation reaction of the photopolymerization initiator (B), improve the reactivity of radical polymerization, and increase the crosslink density. The sensitizer is, for example, 9,10-dibutoxyanthracene, 9-hydroxymethylanthracene, thioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, anthraquinone, 1,2- Dihydroxyanthraquinone, 2-ethylanthraquinone, 1,4-diethoxynaphthalene, p-dimethylaminoacetophenone, p-diethylaminoacetophenone, p-dimethylaminobenzophenone, p-diethylaminobenzophenone, 4,4′-bis (dimethylamino) benzophenone, At least one selected from the group consisting of 4,4'-bis (diethylamino) benzophenone, p-dimethylaminobenzaldehyde, and p-diethylaminobenzaldehyde It may contain one compound.

  The content of the sensitizer in the composition (X) is, for example, 0.1 part by mass or more and 5 parts by mass or less, preferably 0.1 part by mass, based on 100 parts by mass of the solid content of the composition (X). To 3 parts by mass. When the content of the sensitizer is in such a range, the composition (X) can be cured in the air, and the composition (X) needs to be cured under an inert atmosphere such as a nitrogen atmosphere. Disappears.

  The composition (X) may contain a polymerization accelerator in addition to the photopolymerization initiator (B). Examples of the polymerization accelerator include, for example, ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, and butoxy p-dimethylaminobenzoate. Contains amine compounds such as ethyl.

  The composition (X) may further contain a moisture absorbent (D). When the composition (X) contains the hygroscopic agent (D), the cured product of the composition (X) and the sealing material 5 can have a hygroscopic property. For this reason, the sealing material 5 can make it more difficult for moisture to enter the organic EL element 4 in the organic EL light emitting device 1. The average particle size of the moisture absorbent (D) is preferably 200 nm or less. In this case, the cured product can have high transparency.

  The hygroscopic agent (D) is preferably inorganic particles having hygroscopicity, and for example, contains at least one component selected from the group consisting of zeolite particles, silica gel particles, calcium chloride particles, and titanium oxide nanotube particles. Is preferred. It is particularly preferred that the desiccant (D) contains zeolite particles.

  The zeolite particles having an average particle size of 200 nm or less can be produced by, for example, grinding a general industrial zeolite. In producing the zeolite particles, the zeolite may be pulverized and then crystallized by hydrothermal synthesis or the like. In this case, the zeolite particles can have particularly high hygroscopicity. Examples of such a method for producing zeolite particles are disclosed in JP-A-2006-69266, JP-A-2013-049602, and the like.

  When the composition (X) contains the moisture absorbent (D), the ratio of the moisture absorbent (D) to the total amount of the composition (X) is preferably from 1% by mass to 20% by mass. When the proportion of the moisture absorbent (D) is 1% by mass or more, the cured product can have particularly high moisture absorbency. When the proportion of the moisture absorbent (D) is 20% by mass or less, the viscosity of the composition (X) can be particularly reduced, and the composition (X) has a sufficiently low viscosity that can be applied by an inkjet method. Can also. The proportion of the moisture absorbent (D) is more preferably 3% by mass or more, particularly preferably 5% by mass or more. The proportion of the moisture absorbent (D) is more preferably 15% by mass or less, particularly preferably 13% by mass or less.

  When the composition (X) contains a moisture absorbent (D), the composition (X) preferably further contains a dispersant (E). In this case, the dispersant (E) can improve the dispersibility of the moisture absorbent (D) in the composition (X). For this reason, in the composition (X), an increase in viscosity and a decrease in storage stability due to the moisture absorbent (D) hardly occur.

  The dispersant (E) is a surfactant that can be adsorbed on the particles. The dispersant (E) has an adsorptive group (generally also referred to as an anchor) that can be adsorbed on particles, and a molecular skeleton (generally also referred to as a tail) that is adsorbed to the particles by the adsorption group being adsorbed on the particles. The dispersant (E) includes, for example, an acrylic dispersant having a tail having an acrylic molecular chain, a urethane dispersant having a tail having a urethane molecular chain, and a polyester dispersant having a tail having a polyester molecular chain. The composition contains at least one component selected from the group consisting of the agent and the agent. The adsorbing group contains, for example, at least one of a basic polar functional group and an acidic polar functional group. The basic polar functional group includes, for example, at least one group selected from the group consisting of an amino group, an imino group, an amide group, an imide group, and a nitrogen-containing heterocyclic group. The acidic polar functional group includes, for example, at least one group selected from the group consisting of a carboxyl group and a phosphate group. The dispersant (E) is, for example, at least one compound selected from the group consisting of Solsperse series manufactured by Japan Louvre Resol Co., DISPERBYK series manufactured by Big Chemie Japan Co., Ltd., and Azispar series manufactured by Ajinomoto Fine Techno Co., Ltd. Can be contained.

  When the composition (X) contains the hygroscopic agent (D), the amount of the dispersant (E) based on the hygroscopic agent (D) is preferably 5 parts by mass or more and 60 parts by mass or less. When the amount of the dispersant (E) is 5 parts by mass or more, the function of the dispersant (E) can be effectively exhibited, and when the amount is 60 parts by mass or less, the dispersant (E) in the sealing material 5 Free molecules can inhibit the adhesion between the sealing material 5 and the member made of an inorganic material. Further, the amount of the dispersant (D) is more preferably 15 parts by mass or more, more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 30 parts by mass or less. preferable.

  It is preferable that the composition (X) does not contain a solvent. In this case, when preparing a cured product from the composition (X), there is no need to dry the composition (X) to volatilize the solvent. Further, the storage stability of the composition (X) is further increased.

  The composition (X) can be prepared by mixing the above components. The composition (X) is preferably liquid at 25 ° C.

3. Method for Manufacturing Sealing Material and Method for Manufacturing Organic EL Light Emitting Device A method for manufacturing the sealing material 5 using the composition (X) and a method for manufacturing the organic EL light emitting device 1 will be described.

  In the present embodiment, it is preferable to form the sealing material 5 by molding the composition (X) by an inkjet method and then irradiating the composition (X) with ultraviolet rays to cure the composition (X). In the present embodiment, the composition (X) can be applied and molded by an inkjet method.

  In applying the composition (X) by the inkjet method, when the composition (X) has a sufficiently low viscosity at room temperature, for example, when the viscosity at 25 ° C. is 30 mPa · s or less, particularly 15 mPa · s or less. Can be formed by applying the composition (X) by an inkjet method without heating.

  When the composition (X) has a property of being reduced in viscosity by being heated, the composition (X) may be heated and then applied to the composition (X) by an ink-jet method to form the composition. When the viscosity at 40 ° C. of the composition (X) is 30 mPa · s or less, particularly 15 mPa · s or less, the viscosity can be reduced by only slightly heating the composition (X). The composition (X) can be discharged by an inkjet method. The heating temperature of the composition (X) is, for example, 20 ° C or higher and 50 ° C or lower.

  More specifically, for example, first, the support substrate 2 is prepared. A partition 7 is formed on one surface of the support substrate 2 by photolithography using, for example, a photosensitive resin material. Subsequently, a plurality of organic EL elements 4 are provided on one surface of the support substrate 2. The organic EL element 4 can be manufactured by an appropriate method such as an evaporation method and a coating method. In particular, it is preferable to manufacture the organic EL element 4 by a coating method such as an ink jet method. Thereby, the element array 9 is manufactured on the support substrate 2.

  Next, a first passivation layer 61 is provided on the element array 9. The first passivation layer 61 can be manufactured by an evaporation method such as a plasma CVD method.

  Next, the composition (X) is formed on the first passivation layer 61 by, for example, an inkjet method to form a coating film. If the inkjet method is applied to both the formation of the organic EL element 4 and the application of the composition (X), the manufacturing efficiency of the organic EL light emitting device 1 can be particularly improved. Subsequently, the coating film is cured by irradiating the coating material with ultraviolet rays to produce the sealing material 5. The thickness of the sealing material 5 is, for example, not less than 5 μm and not more than 50 μm.

  Next, a second passivation layer 62 is provided on the sealing material 5. The second passivation layer 62 can be manufactured by an evaporation method such as a plasma CVD method.

  Next, an ultraviolet curable resin material is provided on one surface of the support substrate 2 so as to cover the second passivation layer 62, and then the transparent substrate 3 is overlaid on the resin material. The transparent substrate 3 is, for example, a glass substrate or a transparent resin substrate.

  Next, ultraviolet light is applied to the transparent substrate 3 from the outside. The ultraviolet light passes through the transparent substrate 3 and reaches the ultraviolet-curable resin material. Thereby, the ultraviolet curable resin material is cured, and the second sealing material 52 is manufactured.

1. Preparation of Compositions The compositions of Examples and Comparative Examples were prepared by mixing the components shown in the following table.

The details of the components shown in the table are as follows. The viscosity of each of the following components is a value measured using a rheometer (manufactured by Anton Paar Japan, Model No. DHR-2) at a temperature of 25 ° C. and a shear rate of 1000 s ⁻¹ .

(1) Acrylic compound / KBM5103: 3- (trimethoxysilyl) propyl acrylate which is a monofunctional acrylic compound having a silicon atom, product number KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd., viscosity 4 mPa · s, refractive index 1.427, Boiling point 260 ° C.
KR513: an acryl group-containing alkoxysilane oligomer that is a trifunctional or higher acryl compound having a silicon atom, a viscosity of 50 mPa · s, a refractive index of 1.427, and a boiling point of 300 ° C. or higher.
-Light ester P-2M: 2-metacloyloxyethyl acid phosphate, manufactured by Kyoeisha Chemical Co., Ltd., product name light ester P-2M, viscosity 800 mPa-s, refractive index 1.4673, boiling point 300 ° C or higher.
ACMO: acryloylmorpholine, manufactured by KJ Chemical, viscosity 12 mPa · s, glass transition temperature 145 ° C.
3PG: Trifunctional (propylene glycol) dimethacrylate, a bifunctional acrylic compound, manufactured by Shin-Nakamura Chemical Co., Ltd., product number 3PG, viscosity 13 mPa · s, glass transition temperature -8 ° C, refractive index 1.450, boiling point 400 ° C.
APG200: Trifunctional (propylene glycol) diacrylate which is a bifunctional acrylic compound, manufactured by Shin-Nakamura Chemical Co., Ltd., viscosity: 12 mPa · s, glass transition temperature: 55 to 62 ° C, refractive index: 1.449, boiling point: 295 ° C.
SR297: 1,3-butylene glycol dimethacrylate, a bifunctional acrylic compound, manufactured by Sartomer, product number SR297, viscosity 7 mPa · s, glass transition temperature 85 ° C, refractive index 1.449, boiling point 290 ° C.
EBECRYL 145: propylene oxide-modified neopentyl glycol diacrylate, a bifunctional acrylic compound, manufactured by Daicel Ornex, product number EBECRYL 145, viscosity 20 mPa · s, glass transition temperature 60 ° C., refractive index 1.459, boiling point 408 ° C.
-BD: 1,4-butanediol dimethacrylate which is a bifunctional acrylic compound, manufactured by Shin-Nakamura Chemical Co., Ltd., viscosity: 7 mPa · s, glass transition temperature: 55 ° C, refractive index: 1.456, boiling point: 280 ° C.
SR351S: trimethylolpropane triacrylate, a trifunctional acrylic compound, viscosity: 106 mPa · s, glass transition temperature: 62 ° C, refractive index: 1.472, boiling point: 300 ° C or higher, manufactured by Sartomer, part number SR351S.
-SR350NS: trimethylolpropane trimethacrylate, which is a trifunctional acrylic compound, having a viscosity of 44 mPas, a glass transition temperature of 27 ° C, a refractive index of 1.470, a boiling point of 300 ° C or higher, and a product of Sartomer, part number SR350NS.
SR295NS: Pentaerythritol tetraacrylate which is a tetrafunctional acrylic compound, viscosity 342 mPa · s, glass transition temperature 103 ° C, refractive index 1.485, boiling point 300 ° C or higher, manufactured by Sartomer, product number SR295NS.
SR210NS: polyethylene glycol 200 dimethacrylate, viscosity 15 mPa · s, glass transition temperature -9 ° C, refractive index 1.460, boiling point 350 ° C, manufactured by Sartomer, product number SR210NS.
VEEA: 2- (2-vinyloxyethoxy) ethyl acrylate which is a bifunctional radical polymerizable compound, viscosity 4 mPa · s, glass transition temperature 40 ° C, boiling point 260 ° C, manufactured by Nippon Shokubai.
-IBXA: isobornyl acrylate which is a monofunctional acrylic compound, glass transition temperature 97 ° C, viscosity 8 mPa · s, boiling point 260 ° C, manufactured by Osaka Organic Chemical Company.
FA-513AS: dicyclopentanyl acrylate which is a monofunctional acrylic compound, glass transition temperature 120, viscosity 13 mPa · s, boiling point 275 ° C, manufactured by Hitachi Chemical Co., Ltd., product number FA-513AS.

(2) Photopolymerization initiator Irgacure 184: 1-hydroxy-cyclohexyl-phenyl-ketone, manufactured by BASF, trade name Irgacure 184.
-IrgacureTPO: 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by BASF, trade name IrgacureTPO.

2. Evaluation Test The following evaluation tests were performed on the examples and comparative examples. The results are shown in the table.

(1) Transmittance The composition was applied to form a coating film, and the coating film was formed using an LED-UV irradiator (having a peak wavelength of 365 nm) manufactured by Panasonic Electric Works under the conditions of about 50 mW / cm ² . A film having a thickness of 10 μm was produced by irradiating with ultraviolet light for 30 seconds and curing the film. The total light transmittance of this film according to JIS K7361-1 was measured.

(2) Adhesion after moisture absorption A silicon nitride film having a thickness of 1 μm was formed on each surface of two quartz glass pieces (size: 76 mm × 52 mm × 1 mm) by a plasma CVD method to obtain two substrates. The composition was applied on the surface of the silicon nitride film of one substrate to form a coating film having a thickness of 200 μm, and the silicon nitride film of the other substrate was overlaid on the coating film. Subsequently, the coating film was cured by irradiating ultraviolet rays for 30 seconds at about 50 mW / cm ² using an LED-UV irradiator (having a peak wavelength of 365 nm) manufactured by Panasonic Electric Works, Ltd. Thus, a test piece was obtained.

After exposing this test piece to an atmosphere of 85 ° C. and 85 RH, the state of the interface between the coating film and the silicon nitride film was confirmed with a microscope. The results were evaluated as follows. In this test, the higher the adhesion between the coating film and the silicon nitride film and the more the coating film is less likely to absorb moisture, the more difficult it is for the coating film to peel off from the silicon nitride film.
A: Even after exposure to the atmosphere for 96 hours, a portion of the coating film having an area of 50% or more was in close contact with the silicon nitride film.
B: Even if exposed to the atmosphere for 48 hours, 50% or more of the coating does not peel off from the silicon nitride film, and after 96 hours, 50% or more of the coating peels off from the silicon nitride film. Was.
C: Even if exposed to the above atmosphere for 24 hours, a portion having an area of 50% or more of the coating does not peel off from the silicon nitride film, and if exposed for 48 hours, a portion having an area of 50% or more of the coating peels from the silicon nitride film. Was.
D: When exposed to the atmosphere for 24 hours, a portion of the coating film having an area of 50% or more was peeled off from the silicon nitride film.

(3) Volatility The composition was allowed to stand in an argon atmosphere at 20 ° C. (dew point temperature −70 ° C.) for 24 hours. The rate of weight loss of the resulting composition was determined. The case where the weight loss amount was 0.5% or less was evaluated as "A", the case where the weight loss amount was 0.5 to 1% as "B", and the case where the weight loss amount was 1% or more as "C".

(4) Viscosity The viscosity of the composition was measured using a rheometer (manufactured by Anton Paar Japan, model number DHR-2) at a temperature of 25 ° C. and a shear rate of 1000 s ⁻¹ .

(5) Ink jetting property The composition is put into a cartridge of an ink jet printer (manufactured by Ricoh, Model MH2420), and after confirming that the composition in the cartridge can be discharged from a nozzle of the ink jet printer, the composition is discharged from the nozzle. The test pattern was printed continuously. As a result, "A" indicates that the composition could be ejected for one hour and the ejection operation was stable, "B" indicates that the composition could be ejected for one hour but the ejection operation was intermittently unstable, One hour before the start of the discharge, the nozzle was clogged and the composition could not be discharged.

(6) Glass transition temperature The composition was applied to form a coating film, and the coating film was applied to a condition of about 50 mW / cm ² using an LED-UV irradiator (peak wavelength 365 nm) manufactured by Panasonic Electric Works, Ltd. For 30 seconds to produce a film having a thickness of 200 μm. The glass transition temperature of a sample cut out of this film was measured using a viscoelasticity measuring device (manufactured by Hitachi High-Tech Science Corporation, model number DMA7100).

(7) Outgas Evaluation Outgas when the cured product of the composition was heated was sampled by a headspace method and measured by gas chromatography. 100 mg of the composition was placed in a vial for headspace, and the composition was irradiated with ultraviolet rays using an LED-UV irradiator (peak wavelength: 365 nm) manufactured by Panasonic Electric Works Co., Ltd. under the conditions of an integrated light amount of 1500 mJ / cm ² . After curing, the vial was sealed and heated at 80 ° C. for 30 minutes, and then the gas phase in the vial was introduced into a gas chromatograph for analysis. As a result, the case where the generated gas was 300 ppm or less was evaluated as “A”, the case where it was more than 300 ppm and less than 500 ppm was evaluated as “B”, and the case where the generated gas was 500 ppm or more was evaluated as “C”.

Claims (10)

It contains an acrylic compound (A) and a photopolymerization initiator (B),
The acrylic compound (A) has a structure represented by the following formula (1) and contains an acrylic compound (A1) having a boiling point of 270 ° C. or higher,
^{_{CH 2 = CR 1 -COO- (R}} 3 -O) n -CO-CR 2 = CH 2 ... (1)
In the formula (1), each of R ¹ and R ² is hydrogen or a methyl group, n is an integer of 1 or more, R ³ is an alkylene group having 3 or more carbon atoms, and when n is 2 or more, A plurality of R ³ may be the same or different from each other,
A percentage of the acrylic compound (A1) to the acrylic compound (A) is 50% by mass or more;
The acrylic compound (A) does not contain a compound having a boiling point of 260 ° C. or less, or the proportion of the compound having a boiling point of 260 ° C. or less in the acrylic compound (A) is 10% by mass or less.
An ultraviolet curable resin composition for sealing an organic EL element. The viscosity at 25 ° C. of the acrylic compound (A1) is 25 mPa · s or less;
The ultraviolet-curable resin composition according to claim 1. Molded by the inkjet method,
The ultraviolet curable resin composition according to claim 1. The acrylic compound (A) further contains a compound (A21) having three or more (meth) acryloyl groups in one molecule.
The ultraviolet-curable resin composition according to any one of claims 1 to 3. The glass transition temperature of the cured product is 80 ° C. or higher,
The ultraviolet-curable resin composition according to claim 1. The acrylic compound (A) is selected from the group consisting of a compound (A41) having silicon in the molecular skeleton, a compound (A42) having phosphorus in the molecular skeleton, and a compound (A43) having nitrogen in the molecular skeleton. Further containing at least one compound,
The ultraviolet curable resin composition according to any one of claims 1 to 5. In the acrylic compound (A), a percentage of a component having a boiling point of 270 ° C. or more is 80% by mass or more.
The ultraviolet-curable resin composition according to any one of claims 1 to 6. A method for manufacturing an organic EL light emitting device including an organic EL element and a sealing material covering the organic EL element,
After molding the ultraviolet-curable resin composition according to any one of claims 1 to 7 by an ink-jet method, the sealing material is cured by irradiating the ultraviolet-curable resin composition with ultraviolet rays and curing the ultraviolet-curable resin composition. Including making
A method for manufacturing an organic EL light emitting device. After heating the ultraviolet-curable resin composition, the ultraviolet-curable resin composition is molded by an inkjet method,
A method for manufacturing the organic EL light emitting device according to claim 8. An organic EL device, comprising a sealing material covering the organic EL device, wherein the sealing material is a cured product of the ultraviolet-curable resin composition according to any one of claims 1 to 7,
Organic EL light emitting device.