Device structure and its manufacturing method

Abstract

A device structure comprising a multilayer having a substrate and a component portion disposed on the substrate, and a sealing layer sealing the component portion, wherein the sealing layer has a structure in which organic sealing layers and inorganic sealing layers are sequentially stacked relative to the component portion, the inorganic sealing layer comprising silicon nitride, the organic sealing layer comprising a thermoplastic elastomer, and the residual film rate of the organic sealing layer being 90% or more in a dibutyl ether dissolution test. Preferably, the sealing layer comprises a first sealing layer disposed on the component portion, two or more second sealing layers disposed on the first sealing layer, and two or more third sealing layers, and has a structure in which the second sealing layers and the third sealing layers are alternately stacked, wherein the second sealing layer is the aforementioned inorganic sealing layer, and the third sealing layer is the aforementioned organic sealing layer.

Description

[Technical Field]

[0001] This invention relates to a device structure and its manufacturing method. [Previous Technology]

[0002] In devices such as organic electroluminescent devices and flexible touch sensors, it is sometimes required to include structural elements that inhibit the penetration of moisture into the device. For example, an organic electroluminescent device may include a substrate such as a glass plate and an element portion comprising an electrode layer and a light-emitting layer disposed on the substrate. The materials contained in the element portion may deteriorate due to the penetration of moisture. Therefore, in order to inhibit the penetration of moisture into the element portion, a sealing layer is sometimes formed to seal the element portion.

[0003] In many devices, the sealing layer includes an organic sealing layer formed of organic materials and an inorganic sealing layer formed of inorganic materials (Patent Document 1). In the past, organic sealing layers were generally formed under atmospheric pressure. Furthermore, inorganic sealing layers were mostly formed in a vacuum environment by methods such as CVD (Chemical Vapor Deposition).

[0004] However, in the vacuum environment process described in Patent Document 1, the inorganic sealing layer formation apparatus becomes larger and more complex, resulting in high costs. In particular, in processes such as plasma CVD using plasma, plasma dust and other particles are generated, which may cause deterioration of the component.

[0005] Against this background, there is a need for the development of a technology that can form an inorganic sealing layer under atmospheric pressure. In order to meet this need, methods for forming an inorganic sealing layer containing silicon nitride using polysilazane compounds under atmospheric pressure have been developed in recent years (Patent Document 2 and Non-Patent Document 1).

[0006] 『Patent Documents』 《Patent Document 1》: Japanese Patent Publication No. 2018-147812 《Patent Document 2》: Japanese Patent Publication No. 2015-202620

[0007] 《Non-Patent Literature》《Non-Patent Literature 1》: Lina Sun, Kaho Uemura, Tatsuhiro Takahashi, Tsukasa Yoshida, Yoshiyuki Suzuri, "Interfacial Engineering in Solution Processing of Silicon-Based Hybrid Multilayer for High Performance Thin Film Encapsulation" ACS Appl. Mater. Interfaces, 11, 43425-43432 (2019) [Summary of the Invention]

[0008] The sealing layer comprising both inorganic and organic sealing layers containing silicon nitride requires improved sealing performance under high temperature and high humidity conditions. This invention was made in view of the above-mentioned situation, with the aim of providing a device structure comprising silicon nitride and possessing good sealing performance under high temperature and high humidity conditions, and a manufacturing method for easily forming the aforementioned device structure.

[0009] As a result of dedicated research to solve the aforementioned problems, the inventors have obtained the following insights. When using a liquid composition containing a polysilazane compound to form an inorganic sealing layer, dibutyl ether is a suitable solvent due to its minimal impact on the polysilazane compound. However, dibutyl ether is known to easily damage organic sealing layers containing thermoplastic elastomers. Regarding this problem, the inventors have observed, through irradiating the organic sealing layer with vacuum ultraviolet light, that the dibutyl ether tolerance of the organic sealing layer can be improved. The present invention is based on this insight and includes the following.

[0010] [1] A device structure comprising a multilayer having a substrate and an element portion disposed on the substrate, and a sealing layer sealing the element portion, wherein the sealing layer has a structure in which an organic sealing layer and an inorganic sealing layer are sequentially stacked relative to the element portion, the inorganic sealing layer comprising silicon nitride, the organic sealing layer comprising a thermoplastic elastomer, and in a dissolution test for dibutyl ether, the residual film rate of the organic sealing layer is 90% or more.

[0011] [2] The device structure described in [1] includes a first sealing layer disposed on the aforementioned element portion and two or more second sealing layers and two or more third sealing layers disposed on the aforementioned first sealing layer, and has a structure in which the aforementioned second sealing layer and the aforementioned third sealing layer are stacked alternately, wherein the aforementioned second sealing layer is the aforementioned inorganic sealing layer and the aforementioned third sealing layer is the aforementioned organic sealing layer.

[0012] [3]The device structure as described in [1] or [2], wherein the aforementioned first sealing layer is the aforementioned organic sealing layer or a polysiloxane sealing layer containing polysiloxane.

[0013] [4]The device structure described in any one of[1] to[3], wherein the aforementioned thermoplastic elastic system is selected from one or more of the group consisting of hydrogenated aromatic ethylene compound-conjugated diene block copolymer and hydrogenated aromatic ethylene compound-conjugated diene block copolymer modified by silicon-containing polar groups.

[0014] [5] The device structure described in [4] has a structure in which both non-aromatic carbon-carbon unsaturated bonds and aromatic carbon-carbon unsaturated bonds are hydrogenated.

[0015] [6] The device structure described in any one of [1] to [5], wherein the aforementioned organic sealing layer comprises one or more of the group consisting of a moisture absorber and an ultraviolet absorber.

[0016] [7]The device structure described in any of[1] to[6], wherein the thickness of each structural layer included in the aforementioned sealing layer is 300 nm or less.

[0017] [8]The device structure described in any of[1] to[7], wherein the aforementioned element part is an organic electroluminescent element part.

[0018] [9] A method for manufacturing a device structure, comprising a step (a) of preparing a multilayer having a substrate and a component portion disposed on the substrate and a step (b) of forming a sealing layer that seals the component portion, wherein the step (b) of forming the sealing layer comprises a step (b1) of forming an organic sealing layer and a step (b2) of forming an inorganic sealing layer after step (b1), wherein the step (b1) comprises a step (b1-1) of forming an organic intermediate layer containing a thermoplastic elastomer and a step (b1-2) of irradiating the organic intermediate layer with vacuum ultraviolet light, and wherein the step (b2) comprises a step (b2-1) of forming an intermediate layer using a liquid composition containing a polysilazane compound and a solvent and a step (b2-2) of irradiating the intermediate layer with ultraviolet light to obtain an inorganic sealing layer containing silicon nitride.

[0019]

[10] The method for manufacturing a device structure as described in [9], wherein the liquid composition of the aforementioned step (b) contains dibutyl ether as the aforementioned solvent.

[0020]

[11] The method for manufacturing a device structure as described in [9] or

[10] , wherein the aforementioned step (b1-2) includes a step (b1-2-1) of irradiating the aforementioned organic intermediate layer with vacuum ultraviolet light in an inert gas environment and a step (b1-2-2) of irradiating the aforementioned organic intermediate layer after the aforementioned step (b1-2-1) with vacuum ultraviolet light in a mixed gas environment of inert gas and oxygen.

[0021]

[12] A method for manufacturing a device structure as described in any of [9] to

[11] , wherein the aforementioned step (b) includes a step (b3) of forming a first sealing layer, a step (b4) of forming a second sealing layer as an inorganic sealing layer disposed on the aforementioned first sealing layer, and a step (b5) of forming a third sealing layer as an organic sealing layer disposed on the aforementioned second sealing layer, and includes a step of performing the aforementioned step (b4) and the aforementioned step (b5) at least twice, wherein the aforementioned step (b4) is the aforementioned step (b2), and the aforementioned step (b5) is the aforementioned step (b1).

[0022]

[13] The method for manufacturing a device structure as described in

[12] , wherein the aforementioned step (b3) is the aforementioned step (b1), which is the step of forming the aforementioned first sealing layer as the aforementioned organic sealing layer.

[0023] According to the present invention, a device structure comprising silicon nitride and having a sealing layer with good sealing performance in high temperature and high humidity environments can be provided, as well as a manufacturing method for easily forming the aforementioned device structure.

Implementation Method

[0032] The following discloses embodiments and examples to describe the present invention in detail. However, the present invention is not limited to the embodiments and examples disclosed below, and may be implemented in any way without departing from the scope of this application and its equivalents.

[0033] In the following description, unless otherwise noted, "(meth)acrylamide" is a term that includes "acrylamide", "methacrylamide" and combinations thereof. For example, "(meth)acrylate" includes alkyl acrylate, alkyl methacrylate or mixtures thereof.

[0034] In the following description, the term "solvent" is used to refer not only to the medium in the solution, but also to the dispersion medium in which the solid is dispersed.

[0035] [I. Device Structure]

[0036] A device structure system related to one embodiment of the present invention includes a multilayer having a substrate and an element part disposed on the substrate, and a sealing layer sealing the element part, wherein the sealing layer has a structure in which an organic sealing layer and an inorganic sealing layer are stacked sequentially relative to the element part, the inorganic sealing layer includes silicon nitride, the organic sealing layer includes a thermoplastic elastomer, and in a dissolution test for dibutyl ether, the residual film rate of the organic sealing layer is 90% or more.

[0037] Figure 1 is a cross-sectional schematic diagram illustrating a device structure related to one embodiment of the present invention. The device structure 10 includes a multilayer 100 having a substrate 110 and a component portion 120 disposed on the substrate 110, and a sealing layer 200 sealing the component portion 120. The sealing layer 200 has a structure in which an organic sealing layer 210 and an inorganic sealing layer 220 are sequentially stacked relative to the component portion 120. The inorganic sealing layer 220 contains silicon nitride. The organic sealing layer 210 contains a thermoplastic elastomer, and the residual film rate of the organic sealing layer 210 in the dissolution test for dibutyl ether is 90% or more.

[0038] In the device structure 10 shown in FIG1, the following example is disclosed: the sealing layer 200 includes a first sealing layer 201 disposed on the component portion 120, a second sealing layer 202 and a third sealing layer 203 disposed on the first sealing layer 201, and has a structure in which the second sealing layer 202 and the third sealing layer 203 are alternately stacked. The second sealing layer 202 is an inorganic sealing layer 220, and the third sealing layer 203 is an organic sealing layer 210. Furthermore, an example is disclosed where the first sealing layer 201 is a polysiloxane sealing layer 230.

[0039] Here, dibutyl ether is a good solvent for polysilazane compounds because it has low reactivity to polysilazane compounds in the method of forming an inorganic sealing layer using polysilazane compounds. On the other hand, dibutyl ether can sometimes dissolve thermoplastic elastomers. Therefore, when an inorganic sealing layer is stacked on an organic sealing layer to form a sealing layer, the organic sealing layer may deteriorate due to dibutyl ether when a liquid composition containing polysilazane compounds and dibutyl ether is coated on the organic sealing layer, and sometimes the sealing layer as a whole cannot obtain sufficient sealing performance. In contrast, the device structure related to this embodiment has a high residual film rate of the organic sealing layer in the dibutyl ether dissolution test, and therefore the dibutyl ether tolerance of the organic sealing layer is high. Therefore, when the aforementioned liquid composition is coated on the organic sealing layer, the deterioration of the organic sealing layer due to dibutyl ether can also be suppressed. Therefore, since organic and inorganic sealing layers can be stacked in good condition, the sealing performance can be optimized in high temperature and high humidity environments.

[0040] [1. Covering material]

[0041] The coating 10 includes a substrate and an element portion formed on the substrate.

[0042] The substrate 110 may be appropriately selected from those that constitute the device structure. Examples of substrate 110 include: glass plate, resin plate, and resin film. The substrate may have only one layer or multiple layers. For example, a substrate 110 comprising a resin film and a barrier layer disposed on its surface may also be used.

[0043] The component section 120 may be appropriately composed of materials that constitute a device structure. Typically, the component section 120 includes one or more conductive layers. The term "conductive layer" refers to various layers that function by the movement of electrons within the layer. Accordingly, for example, the term "conductive layer" may include not only highly conductive layers such as metals, but also thin organic layers with relatively low conductivity, such as light-emitting layers. In the device structure related to this embodiment, a sealing layer is typically formed to suppress deterioration caused by moisture in the conductive layer.

[0044] Examples of conductor layers include: electrode layers constituting organic electroluminescent elements, light-emitting layers, and combinations thereof; and patterned wiring constituting a touch panel; etc. The conductor layer may also be configured to occupy a wide area on the substrate 110. Furthermore, the conductor layer may be configured to have any surface shape, such as strip, line, rectangle, or dot, similar to the wiring and other structures on the substrate 110.

[0045] The number of conductor layers provided in the element section 120 may be 1 or more. When the element section 120 has 2 or more layers, these layers may be arranged side by side without overlapping, or some or all of these layers may overlap.

[0046] The element section 120 may also include components other than the conductor layer inside or on its surface. Examples of such components include components that maintain the mechanical structure of the element section 120. Specific examples of such components include components of display elements such as liquid crystal cells and organic light-emitting elements.

[0047] FIG. 1 illustrates an organic electroluminescent element portion having a first electrode layer 121, a light-emitting layer 122, and a second electrode layer 123 sequentially in the thickness direction, as an example of element portion 120. The first electrode layer 121, the light-emitting layer 122, and the second electrode layer 123 are all conductive layers. Typically, light is generated by applying a voltage to the first electrode layer 121 and the second electrode layer 123. Examples of materials for the light-emitting layer 122 include polystyrene-based, polyurethane-based, and polyvinylcarbazole-based materials. Furthermore, the light-emitting layer 122 may also be a stack of multiple layers with different light-emitting colors or a mixed layer doped with a pigment different from the color of a certain pigment layer. Moreover, element portion 120 may also include functional layers such as a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, an equipotential surface formation layer, and a charge generation layer (not shown in the figure).

[0048] For example, the multilayer 100 can be manufactured by a manufacturing method that includes forming the element portion 120 on the substrate 110. Examples of methods for forming the element portion 120 include methods such as sputtering and vapor deposition to form a conductor layer on the substrate 110.

[0049] [2. Sealing layer]

[0050] The sealing layer 200 has a structure in which an organic sealing layer 210 and an inorganic sealing layer 220 are sequentially stacked relative to the component portion 120. The sealing layer 200 is a layer body provided in a manner that seals at least a portion of the component portion 120, and is preferably provided in a manner that seals all or most of the component portion 120. In this embodiment, an example is disclosed in which the sealing portion is formed in a manner that seals the entire portion of the surface of the substrate 110 that is not in contact with the component portion.

[0051] [2.1. Layer structure of the sealing layer]

[0052] In the sealing layer, the organic sealing layer and the inorganic sealing layer are typically stacked directly without any other layers between them. In the case of a multilayer structure in which two or more organic sealing layers and two or more inorganic sealing layers are alternately stacked, the multilayer structure includes at least one organic sealing layer and one inorganic sealing layer directly stacked. In this embodiment, it is preferable that the organic sealing layer and the inorganic sealing layer included in the multilayer structure are each directly stacked.

[0053] In the case of a multilayer structure with two or more organic sealing layers and two or more inorganic sealing layers stacked alternately, the number of organic sealing layers and inorganic sealing layers can also be the same. Although not shown in the figure, there can be one more organic sealing layer than inorganic sealing layer, or one less organic sealing layer than inorganic sealing layer. The number of organic sealing layers is preferably two or more, three or more, and ten or less. The number of inorganic sealing layers is preferably two or more, three or more, and ten or less.

[0054] The specific layer structure of the sealing layer should be appropriately selected according to the device structure. For example, as shown in FIG1, the sealing layer 200 may be arranged with the first sealing layer 201, the second sealing layer 202, and the third sealing layer 203 stacked sequentially relative to the component portion 120. In this case, the sealing layer 200 may have, for example, the second sealing layer 202 as an inorganic sealing layer 220 and the third sealing layer 203 as an organic sealing layer 210. When the second sealing layer 202 is an inorganic sealing layer 220 and the third sealing layer 203 is an organic sealing layer 210, it is preferable to have two or more layers of the second sealing layer 202 and two or more layers of the third sealing layer 203, and to have the second sealing layer 202 and the third sealing layer 203 stacked alternately. This is because it can improve the sealing performance of the sealing layer 200.

[0055] As shown in Figure 1, when the sealing layer has a structure in which a first sealing layer, a second sealing layer, and a third sealing layer are sequentially stacked relative to the component, the first sealing layer can be made, for example, an organic sealing layer. Furthermore, the first sealing layer can be made, for example, a polysiloxane sealing layer. Since inorganic sealing layers containing silicon nitride tend to experience increased stress under high temperature and high humidity conditions, they are prone to cracking. Therefore, when the second sealing layer is an inorganic sealing layer, using an organic sealing layer or a polysiloxane sealing layer as the first sealing layer can absorb the stress of the inorganic sealing layer to suppress cracking. Since the first sealing layer can directly seal the component, it is preferable to select a material that considers the impact on the component during the formation of the first sealing layer, depending on the type of component.

[0056] In addition to the layer structure described above, the layer structure that can be adopted as the sealing layer may include, for example, a two-layer structure in which an organic sealing layer and an inorganic sealing layer are stacked sequentially relative to the component part, and a three-layer structure in which an organic sealing layer, an inorganic sealing layer and an organic sealing layer are stacked sequentially relative to the component part.

[0057] [2.2. Organic sealing layer]

[0058] The organic sealing layer comprises a layer of thermoplastic elastomer. Furthermore, the organic sealing layer exhibits a residual film rate of 90% or more in a dissolution test for dibutyl ether.

[0059] The residual film rate of the organic sealing layer in the dibutyl ether dissolution test was obtained by the following measurement method. First, the organic sealing layer was exposed on the surface of the device structure and immersed in dibutyl ether for 60 seconds. Then, it was allowed to air dry. The thickness of the organic sealing layer before immersion in dibutyl ether was defined as T1, and the thickness of the organic sealing layer after immersion in dibutyl ether and air drying was defined as T2. The ratio of T2 to thickness T1 was defined as the residual film rate.

[0060] The residual film rate of the organic sealing layer is 90% or more, preferably 95% or more, better than 98%, and ideally 100%.

[0061] The organic sealing layer is formed on the side closer to the component portion than the inorganic sealing layer. Since the organic sealing layer has high tolerance to dibutyl ether, damage to the organic sealing layer can be suppressed when using a liquid composition containing a polysilazane compound and dibutyl ether to form the inorganic sealing layer. Furthermore, the organic sealing layer can be formed directly on the surface of the component portion, or it can be formed on the surface of the component portion through intermediaries of other layers. When the organic sealing layer is formed directly on the surface of the component portion, it can directly seal the component portion. Here, the term "direct" for sealing the component portion using the layer means that there are no other layers between this layer and the component portion.

[0062] [2.2.1. Material of organic sealing layer]

[0063] (Thermoplastic elastomer)

[0064] A thermoplastic elastomer is a material that exhibits the properties of rubber at room temperature and becomes plasticizable and processable at high temperatures. Such thermoplastic elastomers are characterized by their resistance to elongation and fracture under small loads. Specifically, thermoplastic elastomers exhibit a Young's coefficient of 0.001–1 GPa and an elongation at break (elongation at break) of 100–1000% at 23°C. Furthermore, in a high temperature range above 40°C and below 200°C, the storage elasticity coefficient of thermoplastic elastomers decreases sharply, and the loss tangent (tanδ) (loss elasticity coefficient / storage elasticity coefficient) exhibits a peak or exceeds 1, resulting in softening. The Young's coefficient and elongation at break are measured according to JIS K7113. The loss tangent (tanδ) is measured using a commercially available dynamic viscoelasticity measuring device.

[0065] Thermoplastic elastomers generally do not contain residual solvent, or if they do, the amount is small. Accordingly, thermoplastic elastomers have the advantages of low gas release and the ability to be sealed without simple processes such as cross-linking treatment.

[0066] Polymers may be used as thermoplastic elastomers. Examples of polymers that may be used as thermoplastic elastomers include: ethylene-propylene copolymers and other ethylene-α-olefin copolymers; ethylene-α-olefin-polyene copolymers; copolymers of ethylene and unsaturated carboxylic acid esters such as ethylene-methyl methacrylate copolymers and ethylene-butyl acrylate copolymers; copolymers of ethylene and fatty acid vinyl esters such as ethylene-vinyl acetate copolymers; polymers of alkyl acrylates such as ethyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, and dodecyl acrylate; and diene copolymers such as polybutadiene, polyisoprene, acrylonitrile-butadiene copolymers, butadiene-isoprene copolymers, butadiene-(meth)acrylate alkyl ester copolymers, butadiene-(meth)acrylate alkyl ester-acrylonitrile copolymers, and butadiene-(meth)acrylate alkyl ester-acrylonitrile-styrene copolymers. Butene-isoprene copolymers; styrene-butadiene random copolymers, styrene-isoprene random copolymers, styrene-butadiene block copolymers, styrene-butadiene-styrene block copolymers, styrene-isoprene block copolymers, styrene-isoprene-styrene block copolymers, and other aromatic ethylene compound-conjugated diene copolymers; hydrogenated styrene-butadiene random copolymers, hydrogenated styrene-isoprene random copolymers, hydrogenated styrene-butadiene block copolymers, hydrogenated styrene-butadiene-styrene block copolymers, hydrogenated styrene-isoprene block copolymers, hydrogenated styrene-isoprene-styrene block copolymers, and other hydrogenated aromatic ethylene compound-conjugated diene copolymers; low-crystallinity polybutadiene; styrene-grafted ethylene-propylene elastomers; thermoplastic polyester elastomers; ethylene-based ionomers. Thermoplastic elastomers can be used alone or in any ratio of two or more.

[0067] As a thermoplastic elastomer, hydrogenated aromatic ethylene compound-conjugated diene block copolymers are preferred to achieve the desired effects of the present invention. The term "hydrogenated aromatic ethylene compound-conjugated diene block copolymer" refers to a hydrogenated form of an aromatic ethylene compound-conjugated diene block copolymer. That is, a hydrogenated aromatic ethylene compound-conjugated diene block copolymer represents a polymer having a structure obtained by partially or completely hydrogenating one or more of the non-aromatic carbon-carbon unsaturated bonds, aromatic carbon-carbon bonds, or both of these in the aromatic ethylene compound-conjugated diene block copolymer. However, the aforementioned hydrogenated form is not limited by its manufacturing method.

[0068] As aromatic ethylene compounds, styrene and its derivatives, and ethylenenaphthalene and its derivatives are preferred. In terms of ease of industrial acquisition, styrene is particularly preferred. On the other hand, as conjugated dienes, chain-like conjugated dienes (straight-chain conjugated dienes, branched-chain conjugated dienes) are preferred. Good examples of conjugated dienes include: 1,3-butadiene, isoprene (2-methyl-1,3-butadiene), 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. Among these, 1,3-butadiene and isoprene are particularly preferred in terms of ease of industrial acquisition.

[0069] When the mass fraction of the fully aromatic ethylene monomer unit in the total aromatic ethylene compound-conjugated diene block copolymer is defined as wA, and the mass fraction of the fully conjugated diene monomer unit in the total aromatic ethylene compound-conjugated diene block copolymer is defined as wB, the ratio of wA to wB (wA / wB) is preferably within a specific range. Specifically, the aforementioned ratio (wA / wB) is preferably 20 / 80 or higher, more preferably 30 / 70 or higher, and preferably 60 / 40 or lower, and more preferably 55 / 45 or lower. When the aforementioned ratio wA / wB is above the lower limit of the aforementioned range, the heat resistance of the organic sealing layer can be improved. Furthermore, when it is below the upper limit, the flexibility of the organic sealing layer can be improved. Moreover, when the aforementioned ratio (wA / wB) is within the aforementioned range, since the organic sealing layer can expand the temperature range in which it possesses rubber elasticity, the temperature range in which the device structure possesses flexibility can be expanded.

[0070] As an aromatic ethylene compound-conjugated diene block copolymer, polymers selected from the following are preferred: styrene-butadiene block copolymers, styrene-butadiene-styrene block copolymers, styrene-isoprene block copolymers, styrene-isoprene-styrene block copolymers, and mixtures thereof. More specific examples of such polymers include those described in Japanese Patent Publication No. H2-133406, Japanese Patent Publication No. H2-305814, Japanese Patent Publication No. H3-72512, Japanese Patent Publication No. H3-74409, and International Patent Publication No. 2015 / 099079.

[0071] The hydrogenation rate of the hydrogenated aromatic ethylene compound-conjugated diene block copolymer is preferably above 90%, more preferably above 97%, and especially preferably above 99%. The higher the hydrogenation rate, the better the heat resistance and light resistance of the organic sealing layer can be optimized. The hydrogenation rate of the hydride can be determined by measurement using 1H-NMR.

[0072] The hydrogenation rate of the non-aromatic carbon-carbon unsaturated bonds in the hydrogenated aromatic ethylene compound-conjugated diene block copolymer is preferably above 95%, and more preferably above 99%. A high hydrogenation rate of the non-aromatic carbon-carbon unsaturated bonds can further improve the light resistance and oxidation resistance of the organic sealing layer.

[0073] The hydrogenation rate of the aromatic carbon-carbon unsaturated bonds in the hydrogenated aromatic ethylene compound-conjugated diene block copolymer is preferably 90% or higher, more preferably 93% or higher, and especially preferably 95% or higher. With a high hydrogenation rate of the aromatic carbon-carbon unsaturated bonds, the glass transition temperature of the hydride increases, effectively improving the heat resistance of the organic sealing layer. Furthermore, the photoelasticity coefficient of the organic sealing layer can be reduced to decrease the delay in manifestation.

[0074] Hydrogenated aromatic ethylene compounds-conjugated diene block copolymers are preferably those having a structure that hydrogenates both non-aromatic carbon-carbon unsaturated bonds and aromatic carbon-carbon unsaturated bonds.

[0075] A preferred block configuration for hydrogenated aromatic ethylene compound-conjugated diene block copolymers is a triblock copolymer in which a block [A] of the aromatic ethylene polymer hydride is bonded to both ends of a block [B] of the conjugated diene polymer hydride; a pentablock copolymer in which a polymer block [B] is bonded to both ends of a polymer block [A]; and furthermore, a polymer block [A] is bonded to the other ends of each of the two polymer blocks [B]. In particular, the [A]-[B]-[A] triblock copolymer is preferred because it is easy to manufacture and its properties as a thermoplastic elastomer can be made within the desired range.

[0076] Hydrogenated aromatic ethylene compounds-conjugated diene block copolymers can be manufactured using, for example, the methods described in International Patent Publication No. 2015 / 099079 and Japanese Patent Publication No. 2016-204217.

[0077] Furthermore, polymers having silicon-containing polar groups can also be used as thermoplastic elastomers. Examples of such polymers include modified versions of polymers with silicon-containing polar groups, which are used as thermoplastic elastomers. When a polymer having silicon-containing polar groups is used as the thermoplastic elastomer, the adhesion between the organic sealing layer and other components can be improved.

[0078] Hereinafter, the polymer used in the reaction to obtain the aforementioned modified product is sometimes appropriately referred to as the "pre-reaction polymer". The aforementioned modified product may have a structure, for example, obtained by graft polymerization of the pre-reaction polymer with a compound having a silicon-containing polar group as a monomer. However, the modified product is not limited by its manufacturing method.

[0079] Alkoxysilicon groups are preferred as the polar groups containing silicon atoms. Examples of compounds containing alkoxysilane as a silicon-containing polar group include: vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, dimethoxymethylvinylsilane, diethoxymethylvinylsilane, p-styryltrimethoxysilane, p-styryltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-propenyloxypropyltrimethoxysilane, 3-propenyloxypropyltriethoxysilane, and 2-norphene-5-yltrimethoxysilane, etc., which are vinyl unsaturated silane compounds.

[0080] By reacting a pre-reaction polymer with a compound containing a silicon-atom polar group, the silicon-atom polar group can be introduced into the pre-reaction polymer to obtain a modified product containing a silicon-atom polar group. When an alkoxysilicon group is introduced as the silicon-atom polar group, the amount of alkoxysilicon group introduced relative to 100 parts by weight of the pre-reaction polymer is preferably 0.1 parts by weight or more, more preferably 0.2 parts by weight or more, more preferably 0.3 parts by weight or more, and preferably 10 parts by weight or less, more preferably 5 parts by weight or less, and more preferably 3 parts by weight or less. When the amount of alkoxysilicon group introduced falls within the aforementioned range, high bonding strength can be maintained because the degree of crosslinking between alkoxysilicon groups due to water decomposition can be suppressed from becoming excessively high. Examples of alkoxysilyl-containing substances and modification methods used for introducing alkoxysilyl groups include those described in International Patent Publication No. 2015 / 099079.

[0081] The amount of polar group introduced can be measured by 1H-NMR spectroscopy. Furthermore, when measuring the amount of polar group introduced, if the amount introduced is low, the number of times the measurement is accumulated can be increased.

[0082] Among the thermoplastic elastomers described above, from the viewpoint of significantly achieving the desired effects of the present invention, it is preferable to select one or more from the group consisting of modified products of hydrogenated aromatic ethylene compounds-conjugated diene block copolymers and those modified by silicon-containing polar groups. Among these, modified products of hydrogenated aromatic ethylene compounds-conjugated diene block copolymers by silicon-containing polar groups are particularly preferred.

[0083] Among the modified products of hydrogenated aromatic ethylene compounds-conjugated diene block copolymers due to the introduction of silicon-containing polar groups, it is preferable to introduce alkoxysilane groups as silicon-containing polar groups. Generally, sometimes alkoxysilane groups are introduced as polar groups into pre-reaction polymers such as hydrogenated aromatic ethylene compounds-conjugated diene block copolymers, which is called silane modification. When silane modification is performed, the alkoxysilane groups can be directly bonded to the pre-reaction polymer, or they can be bonded through intermediary divalent organic groups such as alkyl groups. The polymers obtained by silane modification of the pre-reaction polymer are also called "silane modified products".

[0084] Accordingly, as a modified product of hydrogenated aromatic ethylene compound-conjugated diene block copolymer due to the presence of silicon-containing polar groups, a silane-modified product of hydrogenated aromatic ethylene compound-conjugated diene block copolymer is preferred. Among these, a silane-modified product selected from the group consisting of a silane-modified product of hydrogenated styrene-butadiene block copolymer, a silane-modified product of hydrogenated styrene-butadiene-styrene block copolymer, a silane-modified product of hydrogenated styrene-isoprene block copolymer, and a silane-modified product of hydrogenated styrene-isoprene-styrene block copolymer is particularly preferred.

[0085] The weight-average molecular weight (Mw) of the thermoplastic elastomer is not particularly limited, but is preferably 20,000 or more, more preferably 30,000 or more, more preferably 35,000 or more, and preferably 200,000 or less, more preferably 100,000 or less, and more preferably 70,000 or less. The weight-average molecular weight of the thermoplastic elastomer can be measured in the form of a polystyrene equivalent by gel permeation chromatography using tetrahydrofuran as the solvent. Furthermore, the molecular weight distribution (Mw / Mn) of the thermoplastic elastomer is preferably 4 or less, more preferably 3 or less, more preferably 2 or less, and preferably 1 or more. When the weight-average molecular weight Mw and the molecular weight distribution Mw / Mn of the thermoplastic elastomer are within the aforementioned ranges, the mechanical strength and heat resistance of the organic sealing layer can be improved.

[0086] The glass transition temperature of thermoplastic elastomers is not particularly limited, but is preferably above 40°C, more preferably above 70°C, and preferably below 200°C, more preferably below 180°C, and even more preferably below 160°C. Furthermore, when using thermoplastic elastomers containing block copolymers, the glass transition temperature can be adjusted by changing the weight ratio of the respective polymer blocks, thereby achieving a balance between the adhesiveness and flexibility of the organic sealing layer. The glass transition temperature of the resin can be measured using a differential scanning calorimeter (DSC) at a temperature increase of 10°C / minute.

[0087] (Any ingredient)

[0088] In addition to thermoplastic elastomers, the organic sealing layer may also contain any other components. Examples of such components include: hygroscopic particles and ultraviolet absorbers.

[0089] Hygroscopic particles are defined as particles with a high rate of weight change when left to stand at 20°C and 90% RH for 24 hours. The specific range of the aforementioned rate of weight change is typically 3% or more, preferably 10% or more, and more preferably 15% or more. There is no particular upper limit to the rate of weight change, but it may be, for example, below 100%. Hygroscopic particles with such high hygroscopicity can absorb a large amount of moisture in a small amount, thus effectively inhibiting moisture from permeating the sealing layer. As a result, the rubber-like properties of the thermoplastic elastomer are not hindered, which is advantageous.

[0090] The weight change rate of the hygroscopic particles can be calculated by the following formula (K1). In the following formula (K1), W1 represents the weight of the particles before they are placed in an environment of 20°C and 90%RH, and W2 represents the weight of the particles after they are placed in an environment of 20°C and 90%RH for 24 hours.

[0091] Weight change rate (%) = ((W2-W1) / W1) × 100 (K1)

[0092] Examples of materials contained in hygroscopic particles include: alkaline hygroscopic materials and acidic hygroscopic materials. Examples of alkaline hygroscopic materials include: compounds containing alkali metals, alkaline earth metals, and aluminum (oxides, hydroxides, salts, etc.) but not silicon (e.g., barium oxide, magnesium oxide, calcium oxide, strontium oxide, aluminum hydroxide, hydrotalcite, etc.); organometallic compounds as described in Japanese Patent Publication No. 2005-298598; clay containing metal oxides; etc. Furthermore, examples of acidic hygroscopic materials include: inorganic compounds containing silicon (e.g., silicone, nanoporous silica, zeolite).

[0093] The material used as the hygroscopic particle is preferably one or more substances selected from the group consisting of zeolite and hydrotalcite. Zeolite generally has a particularly high hygroscopic capacity. Specifically, zeolite can easily achieve a high weight change rate of 10% to 30% when left to stand at 20°C and 90%RH for 24 hours. Furthermore, since zeolite releases water through drying, it can be reused. The hygroscopic particle material can be used alone or in any combination of two or more types.

[0094] The primary particle diameter of hygroscopic particles is preferably 30 nm or more, more preferably 40 nm or more, and preferably 150 nm or less, with 80 nm or less being particularly desirable. The primary particle diameter of hygroscopic particles refers to the number-average particle diameter of the primary particles. The primary particle diameter of hygroscopic particles can be measured using a particle diameter measurement device employing dynamic light scattering in a dispersion of a solvent. If dynamic light scattering cannot be used to measure the primary particle diameter of hygroscopic particles, it can be measured using an electron microscope. Specifically, it can be measured using the following method: By observing 50 primary particles using an electron microscope, the sum of the minor and major axes of each particle is calculated, and the sum is divided by 2 to measure the particle diameter of each particle. The arithmetic mean of the particle diameters of the 50 primary particles measured in this manner is defined as the primary particle diameter. By observing the particle size using an electron microscope, particles can also be observed in the cross-section of the organic sealing layer.

[0095] The hygroscopic particles have a refractive index of 1.2 or higher and 3.0 or lower at a measurement wavelength of 589 nm. When using hygroscopic particles with this refractive index, the haze of the organic sealing layer can be reduced to achieve a sealing layer with excellent transparency.

[0096] The proportion of hygroscopic particles in the organic sealing layer is not particularly limited and can be adjusted within a range to obtain the desired properties. Specifically, the proportion of hygroscopic particles in the organic sealing layer is preferably 5% by weight or more, more preferably 10% by weight or more, and preferably 60% by weight or less, 40% by weight or less, and 30% by weight or less. When the proportion of hygroscopic particles is at or above the aforementioned lower limit, the water penetration inhibition effect of the organic sealing layer can be improved. Furthermore, when the proportion of hygroscopic particles is at or below the aforementioned upper limit, the transparency of the organic sealing layer can be improved.

[0097] Examples of ultraviolet absorbers include: benzotriazole ultraviolet absorbers, triterpenoid ultraviolet absorbers, diphenyl ketone ultraviolet absorbers, acrylonitrile ultraviolet absorbers, salicylate ultraviolet absorbers, cyanoacrylate ultraviolet absorbers, methylimine ultraviolet absorbers, indole ultraviolet absorbers, naphthalenedimethylimine ultraviolet absorbers, phthalocyanine ultraviolet absorbers, and other organic ultraviolet absorbers. In this embodiment, it is preferable to include one or more absorbers selected from the group consisting of benzotriazole ultraviolet absorbers and triterpenoid ultraviolet absorbers.

[0098] Benzotriazole-based ultraviolet absorbers contain a benzotriazole structure within their molecules. Examples of benzotriazole-based ultraviolet absorbers include: 2,2′-methylenebis[6-(2H-benzotriazole-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol], 2-(2H-benzotriazole-2-yl)-p-cresol, and 2-(5-chloro-2H-benzotriazole-2-yl)-6-tert-butyl-4-methylphenol. Examples of commercially available benzotriazole-based ultraviolet absorbers include: ADK STAB LA-31, ADK STAB LA-32, and ADK STAB LA-36 manufactured by ADEKA.

[0099] Tris(t)-based ultraviolet absorbers contain a tris(t) structure within their molecules. Preferably, compounds containing a 1,3,5-tris(t) structure within their molecules are tris(t)-based ultraviolet absorbers. Examples of tris(t)-based ultraviolet absorbers include: 2,4,6-tris(2-hydroxy-3-methyl-4-hexyloxyphenyl)-1,3,5-tris(t), 2-(4,6-diphenyl-1,3,5-tris(t)-2-yl)-5-(2-(2-ethylhexyloxy)ethoxy)phenol, and 2,4-diphenyl-6-(2-hydroxy-4-hexyloxyphenyl)-1,3,5-tris(t)-. Examples of commercially available triadic ultraviolet absorbers include "ADK STAB LA-F70" and "ADK STAB LA-46" manufactured by ADEKA Corporation, and "Tinuvin 1577" manufactured by BASF Japan Corporation. Another specific example of an ultraviolet absorber is the ultraviolet absorber described in Japanese Patent Publication No. 2017-154401.

[0100] Any components that may be included as a resin composition, in addition to the aforementioned hygroscopic particles and ultraviolet absorbers, may include, for example, dispersants, plasticizers, light stabilizers, antioxidants, lubricants, inorganic fillers, etc. The type, characteristics, and amount of such components may be as described, for example, in International Patent Publication No. 2019 / 220896.

[0101] Any ingredient may be used alone or in any ratio of two or more.

[0102] [2.2.2. Properties of the organic sealing layer]

[0103] The thickness of the organic sealing layer is preferably 1 nm or more, more preferably 10 nm or more, more preferably 80 nm or more, and preferably 300 nm or less, more preferably 200 μm or less, and especially preferably 150 μm or less. When the thickness of the organic sealing layer is at or above the aforementioned lower limit, the penetration of moisture can be effectively suppressed. Furthermore, when the thickness of the organic sealing layer is below the aforementioned upper limit, the thickness of the device structure can be reduced. Here, the thickness of the organic sealing layer refers to the thickness of each individual organic sealing layer.

[0104] The haze of the organic sealing layer is preferably below 0.5%, more preferably below 0.15%, and especially preferably below 0.05%. When the haze is below the above range, the transparency of the organic sealing layer is improved, making it suitable for use in device structures such as organic electroluminescent devices and flexible touch sensors where light transmission is required. The haze can be measured using a turbidimeter.

[0105] [2.3. Inorganic sealing layer]

[0106] The inorganic sealing layer is a layer containing silicon nitride. In addition to silicon nitride, the inorganic sealing layer may also contain, for example, silicon oxide and silicon oxynitride.

[0107] This inorganic sealing layer may be formed using a polysilazane compound. More specifically, it may be formed using the forming method described in the section [II. Method for Manufacturing Device Structure] below.

[0108] The thickness of the inorganic sealing layer is preferably 1 nm or more, more preferably 10 nm or more, and preferably 300 nm or less, more preferably 200 nm or less, and especially preferably 150 nm or less. When the thickness of the inorganic sealing layer is above or below the aforementioned lower limit, the penetration of moisture can be effectively suppressed. Furthermore, when the thickness of the inorganic sealing layer is below or below the aforementioned upper limit, the thickness of the device structure can be reduced. Here, the thickness of the inorganic sealing layer refers to the thickness of each individual inorganic sealing layer.

[0109] [2.4. Polysiloxane sealing layer]

[0110] In addition to the aforementioned organic and inorganic sealing layers, the sealing layer related to this embodiment may also include, for example, a polysiloxane sealing layer. The polysiloxane sealing layer, for example, comprises a compound whose main skeleton is a silicate formed by Si-O bonds with high bond energy; more specifically, it comprises an organic polysiloxane. Examples of organic polysiloxanes include, for instance, dimethyl polysiloxane. Furthermore, the polysiloxane sealing layer is preferably made of polysiloxane rubber (polysiloxane elastomer). The thickness of the polysiloxane sealing layer is preferably 1 nm or more, more preferably 10 nm or more, more preferably 80 nm or more, and preferably 300 nm or less, and more preferably 200 nm or less.

[0111] [2.5. Sealing layer]

[0112] The overall thickness of the sealing layer can be appropriately adjusted within the range where the sealing layer, as a device structure, can achieve the desired sealing performance. The overall thickness of the sealing layer is preferably 0.7 μm or more, more preferably 1 μm or more, and preferably 10 μm or less, and more preferably 5 μm or less. The sealing layer of this embodiment, by having a structure with the aforementioned organic and inorganic sealing layers stacked together, can achieve good sealing performance with a thin thickness.

[0113] The thickness of each structural layer constituting the sealing layer is preferably 300 nm or less, and preferably 200 nm or less. Furthermore, the lower limit of the thickness of each structural layer is set to, for example, 1 nm or more.

[0114] [3. Device Structure]

[0115] As described in the above-described embodiment, the device structure 10, which includes an organic electroluminescent element as an element part 120, can be used, for example, as a display device, a lighting device, or other device. However, the device structure is not limited to such devices. The device structure can include a wide range of devices including the element part and assemblies that form part of such devices. Among them, since the sealing layer of the device structure described above has excellent transparency, it is preferable to use various optical devices and assemblies that form part of the optical devices as the device structure. Examples of optical devices include: liquid crystal display devices, touch panels, and display devices and organic electroluminescent devices that serve as light source devices. In particular, it is preferable to use the device structure as a flexible optical device by utilizing the excellent characteristics of the so-called flexible organic electroluminescent element.

[0116] [II. Manufacturing method of device structure]

[0117] A method for manufacturing a device structure related to one embodiment of the present invention includes a step (a) of preparing a multilayer having a substrate and a component portion disposed on the substrate, and a step (b) of forming a sealing layer that seals the component portion. The step (b) of forming the sealing layer includes a step (b1) of forming an organic sealing layer and a step (b2) of forming an inorganic sealing layer after step (b1). The step (b1) includes a step (b1-1) of forming an organic intermediate layer containing a thermoplastic elastomer and a step (b1-2) of irradiating the organic intermediate layer with vacuum ultraviolet light. The step (b2) includes a step (b2-1) of forming an intermediate layer using a liquid composition containing a polysilazane compound and a solvent and a step (b2-2) of irradiating the intermediate layer with ultraviolet light to obtain an inorganic sealing layer containing silicon nitride.

[0118] Figures 2 to 6 are cross-sectional views illustrating a method for manufacturing a device structure related to one embodiment of the present invention. Figures 2 to 6 show an example where, in step (b) of forming the sealing layer 200, a sealing layer 200 is formed relative to the element portion 120, consisting of a first sealing layer 201, a second sealing layer 202, a third sealing layer 203, and another second sealing layer 202 and a third sealing layer 203 stacked sequentially. In this example, the manufacturing method of the device structure 10, as shown in Figure 2, involves preparing a multilayer 100 comprising a substrate 110 and an element portion 120 disposed on the substrate 110 (step (a)). Next, as shown in Figure 3, a first sealing layer 201 is formed relative to the element portion 120 (step (b3)). Figure 3 shows an example of forming a polysiloxane sealing layer 230 as the first sealing layer 201. Next, as shown in FIG4, a second sealing layer 202, serving as an inorganic sealing layer 220, is formed on the first sealing layer 201 (step (b4)). Next, as shown in FIG5, a third sealing layer 203, serving as an organic sealing layer 210, is formed on the second sealing layer 202 (step (b5)). Next, as shown in FIG6, the sealing layer 200 is formed by further repeating the aforementioned steps (b4) and (b5).

[0119] In step (b1) of the manufacturing method of the device structure related to this embodiment, the resistance of the polysilazane compound to the solvent is improved by irradiating the organic intermediate layer with vacuum ultraviolet light. Therefore, when an inorganic sealing layer is formed on the organic sealing layer, the deterioration of the organic sealing layer caused by the solvent of the polysilazane compound can be suppressed, and a sealing layer with good sealing performance can be formed.

[0120] The inventors speculate the following reasons for the improvement of the solvent resistance of polysilazane compounds by irradiating the organic sealing layer with vacuum ultraviolet light. However, the scope of the present invention is not limited by the following mechanism.

[0121] It can be inferred that when a liquid composition containing a polysilazane compound and a solvent is applied to an organic sealing layer, damage may occur due to the solvent penetrating into the organic sealing layer. In contrast, it can be inferred that by irradiating the organic sealing layer with vacuum ultraviolet light, the surface of the organic sealing layer will be densified, making it less permeable to the solvent, thereby suppressing damage.

[0122] [1. Process (a): Preparation of the coating material]

[0123] Step (a) is the step of preparing the coating. The coating may be prepared by manufacturing it in-house or by purchasing it from another party. The coating is defined as being the same as the content described in the above-mentioned item

I. Device Structure

[0124] [2. Process (b): Formation of the sealing layer]

[0125] Step (b) of forming the sealing layer includes step (b1) of forming an organic sealing layer and step (b2) of forming an inorganic sealing layer after step (b1). Step (b) includes at least steps (b1) and (b2) performed sequentially. Since the sealing layer preferably has a structure in which two or more organic sealing layers and two or more inorganic sealing layers are stacked alternately, it is preferable that steps (b1) and (b2) are repeated two or more times. In this case, steps (b1) and (b2) can be repeated sequentially, or steps (b2) and (b1) can be repeated sequentially.

[0126] [2.1. Process (b1): Formation of organic sealing layer]

[0127] The process of forming the organic sealing layer includes the process of forming an organic intermediate layer containing a thermoplastic elastomer (b1-1) and the process of irradiating the aforementioned organic intermediate layer with vacuum ultraviolet light to obtain the aforementioned organic sealing layer (b1-2).

[0128] [2.1.1. Process (b1-1): Formation of the organic intermediate layer]

[0129] Step (b1-1) is the process of forming an organic intermediate layer containing a thermoplastic elastomer. The organic intermediate layer is a layer containing a resin composition of thermoplastic elastomer, which is obtained in the stage prior to vacuum ultraviolet irradiation.

[0130] The method for forming the organic intermediate layer is preferably a process in which a layer of resin composition comprising a thermoplastic elastomer and a solvent is formed, and then the layer of resin composition is dried to obtain the organic intermediate layer. In order to distinguish it from the solvent used in the formation of the inorganic sealing layer, the solvent contained in the resin composition is sometimes referred to as the "first solvent".

[0131] The resin composition includes a thermoplastic elastomer and a first solvent. It is preferred that the resin composition includes any component. The thermoplastic elastomer and any component are defined as being identical to those described in the items [I. Device Structure] [2. Sealing Layer] [2.2. Organic Sealing Layer] above.

[0132] The first solvent may be a solvent capable of dissolving or dispersing the thermoplastic elastomer. Furthermore, the first solvent may be used alone or in combination of two or more. Since the component being sealed generally has low moisture resistance, a non-aqueous solvent is preferred as the first solvent. Moreover, from the viewpoint of suppressing damage to the component and effectively suppressing moisture penetration, a non-polar solvent is preferred as the first solvent.

[0133] As non-polar solvents, examples include: cyclohexane, methylcyclohexane, ethylcyclohexane, hexane, toluene, benzene, xylene, decahydronaphthalene, tetrahydronaphthalene, trimethylbenzene, cyclooctane, cyclodecane, octane (e.g., n-octane), dodecane, tridecane, tetradecane, and cyclododecane, etc.

[0134] The total amount of the first solvent is set at 100% by weight. The amount of non-polar solvent is preferably 95% by weight or more, preferably 99% by weight or more, and even more preferably 99.9% by weight or more. Ideally, it is 100% by weight.

[0135] The first solvent is preferably a high-boiling-point solvent. The boiling point of the high-boiling-point solvent at 1 atm (1.01325 × 10⁵ Pa) is preferably 90°C or higher, more preferably 100°C or higher, even more preferably 125°C or higher, even more preferably 150°C or higher, and especially preferably 175°C or higher. When the first solvent contains a high-boiling-point solvent, uneven surface formation of the organic sealing layer obtained by drying the organic intermediate layer, which is a layer of resin composition containing the first solvent, can be suppressed, resulting in a smooth surface. Furthermore, nozzle clogging during coating of the resin composition using inkjet printing can generally be suppressed. The upper limit of the boiling point of the high-boiling-point solvent at 1 atm is preferably 300°C or lower, and more preferably 250°C or lower. When the boiling point of the high-boiling-point solvent is below the upper limit of the aforementioned range, the drying of the organic intermediate layer can be easily performed.

[0136] Relative to the total amount of the first solvent (100% by weight), the amount of high-boiling-point solvent is preferably 10% by weight or more, preferably 25% by weight or more, preferably 50% by weight or more, preferably 70% by weight or more, especially preferably 80% by weight or more, and usually less than 100% by weight.

[0137] The resin composition is preferably a liquid composition. By using a liquid resin composition, an organic intermediate layer can be easily formed by coating. The viscosity of this liquid resin composition is preferably 1 cP or more, more preferably 2 cP or more, especially 3 cP or more, and preferably 5000 cP or less, more preferably 1000 cP or less, even better 500 cP or less, even better 50 cP or less, even better 30 cP or less, and especially better 20 cP or less. When the viscosity of the resin composition is above or below the lower limit of the aforementioned range, the thickness of the organic intermediate layer can be easily adjusted, and an organic sealing layer with the desired thickness can be easily formed. Furthermore, when the viscosity of the resin composition is below or above the upper limit of the aforementioned range, the formation of the organic intermediate layer by coating can be easily performed. In particular, when the viscosity is 50 cP or less, the organic intermediate layer can be formed by inkjet printing. Viscosity was measured using a tuning fork vibratory viscometer (e.g., the SV-10 tuning fork vibratory viscometer manufactured by A&D Corporation) at a measurement temperature of 25℃±2℃.

[0138] The proportion of solid components contained in the resin composition is not particularly limited, but it is preferable to adjust the viscosity and other properties to fit within a desired range. Specifically, the amount of solid components in 100% by weight of the total resin composition is preferably 1% by weight or more, more preferably 3% by weight or more, more preferably 40% by weight or less, more preferably 30% by weight or less, and even more preferably 20% by weight or less.

[0139] As a method for forming the organic intermediate layer, it is preferable to coat the resin composition by preparing the aforementioned resin composition comprising a thermoplastic elastomer and a first solvent. In this way, the organic intermediate layer can be easily formed.

[0140] Examples of coating methods include: curtain coating, extrusion coating, roller coating, spin coating, dip coating, bar coating, spray coating, slant coating, printing coating, rotary gravure coating, die coating, gap coating, and impregnation. Among these, screen printing and inkjet printing are preferred, with inkjet printing being particularly preferred.

[0141] When a resin composition layer contains a first solvent, the resin composition is coated and then dried to remove the first solvent. Examples of drying methods for the resin composition layer include natural drying, heat drying, reduced pressure drying, and reduced pressure heat drying. In cases where natural drying is achieved simply by placing the layer at room temperature for a short time, specific drying operations become unnecessary. However, since the resin composition layer may typically contain a large amount of the first solvent, it is preferable to promote drying through operations such as heating or reducing pressure. By drying the resin composition layer, the first solvent can be removed from the resin composition layer to obtain an organic intermediate layer formed from the solid components of the resin composition.

[0142] [2.1.2. Process (b1-2): Vacuum ultraviolet irradiation]

[0143] Step (b1-2) is the process of irradiating the aforementioned organic intermediate layer with vacuum ultraviolet light to obtain the aforementioned organic sealing layer. By performing step (b1-2), the dibutyl ether tolerance of the organic sealing layer can be improved.

[0144] As vacuum ultraviolet light, light with a wavelength of 100 nm to 200 nm must be used. Examples of vacuum ultraviolet light sources include rare gas excimer lamps. Among them, Xe excimer lamps have excellent luminous efficiency because they emit ultraviolet light with a short wavelength of 172 nm in a single wavelength.

[0145] The irradiation conditions for vacuum ultraviolet light can be appropriately adjusted within the range where the desired organic sealing layer can be obtained. In this embodiment, it is preferable to set the irradiation conditions to include the following steps: step (b1-2-1) of irradiating the aforementioned organic intermediate layer with vacuum ultraviolet light in an inert gas environment, and step (b1-2-2) of irradiating the aforementioned organic intermediate layer after step (b1-2-1) with vacuum ultraviolet light in a mixed gas environment of inert gas and oxygen. When irradiating with vacuum ultraviolet light in an inert gas environment, the surface of the organic sealing layer can be given solvent resistance, but on the other hand, there is a tendency to reduce the wettability of the solvent, and there is a tendency to make it easier to repel liquid components. Therefore, it is preferable to irradiate with vacuum ultraviolet light in an inert gas environment to give solvent resistance, and then irradiate with vacuum ultraviolet light in a mixed gas environment of inert gas and oxygen to modify a portion of the surface of the organic sealing layer, so as to improve the coating properties of the solvent.

[0146] The "inert gas environment" in process (b1-2-1) includes not only an inert gas environment but also a gas environment containing inert gas and trace amounts of oxygen. Specifically, the oxygen concentration in the aforementioned gas environment under the inert gas environment is preferably 500 ppm or higher, more preferably 1000 ppm or higher, more preferably 10000 ppm or lower, and more preferably 5000 ppm or lower. The aforementioned unit "ppm" refers to a quality standard.

[0147] Examples of inert gases include nitrogen, helium, neon, and argon, with nitrogen being preferred. Furthermore, one inert gas can be used alone, or two or more can be used in combination. For example, when using inert gases, ultraviolet irradiation can be performed in the treatment chamber where the inert gas is supplied and discharged. In this case, the flow rates of oxygen and inert gas introduced into the treatment chamber can be adjusted to regulate the oxygen concentration in the gaseous environment.

[0148] The intensity of vacuum ultraviolet irradiation in an inert gas environment can be appropriately adjusted within the range from which the desired organic sealing layer can be obtained. If a specific range is specified, an irradiation intensity of 30 mW / cm² or higher is preferred, 40 mW / cm² or higher is more preferred, 50 mW / cm² or higher is even more preferred, and 100 mW / cm² or lower is preferred, 80 mW / cm² or lower is more preferred, and 60 mW / cm² or lower is even more preferred.

[0149] The irradiation time of vacuum ultraviolet light in an inert gas environment can be appropriately adjusted within the range where the desired organic sealing layer can be obtained. If a specific range is specified, an irradiation time of 100 seconds or more is preferred, 150 seconds or more is even more preferred, 300 seconds or less is preferred, and 250 seconds or less is even more preferred.

[0150] The "mixed gas environment of inert gas and oxygen" in process (b1-2-2) refers to a gas environment containing both inert gas and oxygen. The oxygen concentration can be adjusted to the extent that it changes the wettability of the solvent on the surface of the organic sealing layer. Specifically, an oxygen concentration of 1% or more is preferred, 3% or more is preferable, and 20% or less is preferred, with 10% or less being preferable. The aforementioned unit "%" refers to quality standards.

[0151] Furthermore, the intensity of vacuum ultraviolet irradiation in a mixed gas environment of inert gas and oxygen can be appropriately adjusted within the range from which the desired organic sealing layer can be obtained. If a specific range is disclosed, an irradiation intensity of 30 mW / cm² or higher is preferred, 40 mW / cm² or higher is more preferred, 50 mW / cm² or higher is even more preferred, and 100 mW / cm² or lower is preferred, 80 mW / cm² or lower is more preferred, and 60 mW / cm² or lower is even more preferred.

[0152] The irradiation time of vacuum ultraviolet light in a mixed gas environment of inert gas and oxygen can be appropriately adjusted within the range in which the desired organic sealing layer can be obtained. If a specific range is to be disclosed, 100 seconds or more is preferred, 150 seconds or more is even more preferred, 300 seconds or less is preferred, and 250 seconds or less is even more preferred.

[0153] The irradiation conditions, such as the intensity and duration of vacuum ultraviolet irradiation in process (b1-2), can be adjusted, for example, by the reduction in the intensity of the C-H stretching peak in the FT-IR spectrum of the organic intermediate layer (organic sealing layer) before and after vacuum ultraviolet irradiation. Specifically, it is preferable to set the irradiation conditions such that when the intensity of the C-H stretching peak in the FT-IR spectrum of the organic intermediate layer before vacuum ultraviolet irradiation is set to I1 and the intensity of the C-H stretching peak in the FT-IR spectrum of the organic intermediate layer after vacuum ultraviolet irradiation is set to I2, the ratio of I2 to I1 (I2 / I1) is 50% or less. Furthermore, it is preferable to set the I2 / I1 ratio to be 20% or more. This is because when I2 / I1 is within the above range, it is easy to obtain an organic sealing layer with good dibutyl ether tolerance. The C-H stretching peak in the FT-IR spectrum can be observed in the range of, for example, 2960 cm⁻¹ to 2850 cm⁻¹.

[0154] [2.2. Process (b2): Formation of inorganic sealing layer]

[0155] The step (b2) of forming the inorganic sealing layer includes a step (b2-1) of forming an intermediate layer using a liquid composition containing a polysilazane compound and a solvent, and a step (b2-2) of irradiating the aforementioned intermediate layer with ultraviolet light to obtain an inorganic sealing layer containing silicon nitride. Since the inorganic sealing layer is formed on the organic sealing layer, it can indirectly seal the component. In the case where the sealing layer has two or more inorganic sealing layers, for example, the inorganic sealing layer can also be formed directly on the component.

[0156] [2.2.1. Process (b2-1): Formation of intermediate layer]

[0157] Step (b2) includes a step (b2-1) of forming an intermediate layer using a liquid composition containing a polysilazane compound and a solvent. The intermediate layer is a layer containing a polysilazane compound.

[0158] The formation of the aforementioned intermediate layer containing a polysilazane compound is preferably carried out by a method including coating a liquid composition containing a polysilazane compound and a solvent. According to this method, the intermediate layer can be easily formed.

[0159] A polysilazane compound is a polymer having a silicon-nitrogen bond. As the polysilazane compound, for example, a polysilazane compound that can be used as a precursor of ceramics such as SiO2, Si3N4, and an intermediate solid solution SiOxNy of both can also be used.

[0160] As a good polysilazane compound, for example, a compound containing a repeating unit represented by the following formula (1) can be cited.

[0161] [Chemical formula 1]

[0162] In formula (1), R1, R2, and R3 each independently represent one or more groups selected from the group consisting of a hydrogen atom and a monovalent organic group. As the monovalent organic group, examples include aliphatic hydrocarbon groups such as alkyl and alkenyl; alicyclic hydrocarbon groups such as cycloalkyl; aromatic hydrocarbon groups such as aryl; alkylsilyl; alkylamino; alkoxy; etc. As the polysilazane compound represented by formula (1), those described in Japanese Patent Laid-Open No. H8-112879 can also be used.

[0163] Among them, from the viewpoint of obtaining an inorganic sealing layer with excellent sealing ability, R1, R2, and R3 are preferably hydrogen atoms. A polysilazane compound in which any one of R1, R2, and R3 in the repeating unit is a hydrogen atom is sometimes referred to as a perhydro polysilazane. The number average molecular weight (Mn) of the perhydro polysilazane, for example, can be about 600 to 2000 (in terms of polystyrene).

[0164] As another good polysilazane compound, examples include: alkoxysilane addition polysilazane obtained by reacting alkoxysilane with a polysilazane compound containing repeating units as shown in formula (1) (Japanese Patent Publication No. H5-238827); 2,3-epoxypropanol addition polysilazane obtained by reacting 2,3-epoxypropanol (Japanese Patent Publication No. H6-122852); and alcohol addition polysilazane obtained by reacting an alcohol (Japanese Patent Publication No. H6-122852). Japanese Patent Publication No. H6-240208, a metal carboxylate addition polysilazane obtained by reacting a metal carboxylate (Japanese Patent Publication No. H6-299118), an acetyl acetone addition polysilazane obtained by reacting a metal-containing acetone complex (Japanese Patent Publication No. H6-306329), and a metal microparticle-added polysilazane obtained by adding metal microparticles (Japanese Patent Publication No. H7-196986), etc.

[0165] A single polysilazane compound may be used alone, or two or more may be used in combination. For example, a combination of perhydropolysilazane and an organopolysilazane in which one of the hydrogen atoms of the Si atom of the perhydropolysilazane is partially substituted with an organic group such as an alkyl group may be used. When perhydropolysilazane and organopolysilazane are used in combination, cracking can be suppressed because the toughness of the second sealing layer can be improved. In particular, when methyl-substituted organopolysilazane is used in combination with perhydropolysilazane, the toughness can be significantly improved.

[0166] Furthermore, perhydropolysilazane may be used alone as the polysilazane compound. Inorganic sealing layers formed using only perhydropolysilazane are particularly prone to cracking. In this embodiment, even when an inorganic sealing layer that is prone to cracking is formed, cracking can be suppressed by combining it with an organic sealing layer.

[0167] Polysilazane compounds are generally available as liquid or solid compounds. Such polysilazane compounds may also be commercially available.

[0168] The liquid composition typically contains a solvent. To distinguish it from the first solvent used in the formation of the organic intermediate layer, the solvent used in the formation of the intermediate layer is sometimes referred to as the "second solvent." As the second solvent, a solvent containing dibutyl ether is preferred. The content of dibutyl ether in the second solvent is preferably 50% by weight or more, more preferably 70% by weight or more, and even more preferably 90% by weight or more. In step (b1), by irradiating with vacuum ultraviolet light, the dibutyl ether tolerance of the organic sealing layer can be improved, because by using dibutyl ether as the second solvent, the effects caused by this embodiment can be highly utilized.

[0169] Furthermore, as the second solvent, a solvent in which the residual film rate of the organic sealing layer in the dissolution test of the second solvent is 90% or more may also be used. In order to select the second solvent, in this embodiment, a step (b2-3) may also be included to select a second solvent in which the residual film rate of the aforementioned organic sealing layer is 90% or more in the dissolution test of the second solvent. In the selection of the second solvent, for example, a sample with an organic sealing layer formed is prepared on a support substrate such as a silicon substrate under the same conditions as in step (b1), and after being irradiated with vacuum ultraviolet light, the sample is immersed in the second solvent and dried under the same conditions as in the dissolution test of the aforementioned dibutyl ether. The residual film rate is calculated from the thickness of the organic sealing layer before and after immersion, and a solvent with a residual film rate of 90% or more can be selected as the second solvent. The conditions for irradiation with vacuum ultraviolet light are, for example, irradiation with vacuum ultraviolet light (VUV (172 nm)) for 3 minutes at a temperature of 23-25°C and a humidity of 50-60%, in an inert gas environment (e.g., nitrogen environment), and an illuminance of 30 mW / cm2.

[0170] Examples of a second solvent include: hydrocarbon solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons; halogenated hydrocarbon solvents; and ether solvents such as aliphatic ether solvents and alicyclic ether solvents. Specific examples include: hydrocarbon solvents such as pentane, hexane, cyclohexane, toluene, xylene, solvesse, and turpentine; halogenated hydrocarbon solvents such as dichloromethane and trichloroethane; and ether solvents such as dibutyl ether, dioxane, and tetrahydrofuran. A single second solvent can be used, or two or more solvents can be used in any ratio.

[0171] The amount of the second solvent in the liquid composition is preferably adjusted in such a way that the concentration of the polysilazane compound in the liquid composition is contained within an appropriate range. Specifically, the amount of the polysilazane compound relative to 100% by weight of the total liquid composition is preferably 0.2% to 35% by weight.

[0172] The liquid composition may also contain any components other than the polysilazane compound and the second solvent.

[0173] There are no particular limitations on the coating method for the liquid composition. As an example of the coating method, the same method as that used for coating resin compositions used in the formation of organic intermediate layers can also be used. By this coating, an intermediate layer of liquid composition can be formed under atmospheric pressure.

[0174] Since the intermediate layer contains the second solvent, step (b2-1) may also include step (b2-4) of drying the intermediate layer. Drying may also be performed simultaneously with step (b2-2), but it is preferable to perform it before step (b2-2). Through drying, the second solvent can be removed from the intermediate layer.

[0175] The drying of the intermediate layer is preferably carried out in a gaseous environment with a low oxygen concentration. Specifically, the oxygen concentration of the aforementioned gaseous environment is preferably 10% or less, and more preferably 5% or less. By carrying out drying in such a gaseous environment with a low oxygen concentration, the introduction of oxygen into the intermediate layer can be suppressed. Accordingly, since the absorption of ultraviolet light irradiated in process (b2-2) by oxygen can be suppressed, the reaction of the polysilazane compound can proceed stably.

[0176] From the perspective of drying in a low-oxygen-concentration gas environment, the drying of the intermediate layer is preferably carried out in an inert gas environment. Examples of inert gases include nitrogen, helium, neon, and argon, with nitrogen being the most preferred. Furthermore, one inert gas can be used alone, or two or more can be used in combination. For example, when using an inert gas, drying can be carried out in a drying chamber that supplies and discharges the inert gas. Heating can also be performed during drying.

[0177] [2.2.2. Process (b2-2): Irradiation of the intermediate layer by ultraviolet light]

[0178] Step (b2) includes step (b2-2) of irradiating the intermediate layer with ultraviolet light after obtaining the intermediate layer in step (b2-1). By irradiating the intermediate layer with ultraviolet light, the polysilazane compound contained in the intermediate layer reacts to obtain an inorganic sealing layer containing silicon nitride.

[0179] As ultraviolet light, light with a wavelength of 1 nm to 380 nm may be used. Among them, vacuum ultraviolet light with a wavelength of 100 nm to 200 nm is preferred. By irradiating with vacuum ultraviolet light, the modification reaction of polysilazane compounds can be carried out in a short time, thus suppressing damage to the component and organic sealing layer caused by ultraviolet light. The light source for vacuum ultraviolet light shall be the same as that described in the aforementioned item [2.1.2. Process (b1-2): Irradiation with vacuum ultraviolet light].

[0180] The intensity of ultraviolet (UV) irradiation can be appropriately adjusted within a range from which the desired inorganic sealing layer can be obtained. Specifically, an irradiation intensity of 10 mW / cm² or higher is preferred, 100 mW / cm² or higher is more preferred, and 300 mW / cm² or lower is preferred, with 200 mW / cm² or lower being more desirable. Step (b2-2) preferably includes at least one UV irradiation at the maximum irradiation intensity of 100 mW / cm² to 200 mW / cm². Under this intensity of UV irradiation, the modification reaction of the polysilazane compound can be carried out in a short time, or damage to the component and organic sealing layer caused by UV irradiation can be suppressed.

[0181] The irradiation time of ultraviolet light can be appropriately adjusted within the range where the desired inorganic sealing layer can be obtained. Specifically, an irradiation time of 0.1 seconds or more is preferred, 0.5 seconds or more is even better, and 10 minutes or less is preferable, 3 minutes or less is preferable, and 1 minute or less is even more preferable. Under such irradiation time, the modification reaction of the polysilazane compound can be fully carried out to reduce inconsistencies in sealing performance, or to suppress damage to the component and organic sealing layer caused by ultraviolet light.

[0182] The aforementioned ultraviolet irradiation is preferably carried out in a gaseous environment with low oxygen concentration. Specifically, the oxygen concentration of the aforementioned gaseous environment is preferably 500 ppm or higher, more preferably 1000 ppm or higher, and preferably 10000 ppm or lower, and more preferably 5000 ppm or lower. The aforementioned unit "ppm" refers to a mass standard. When the oxygen concentration of the gaseous environment irradiating ultraviolet light is within the aforementioned range, the modification reaction of the polysilazane compound can be effectively promoted, and the sealing ability of the obtained inorganic sealing layer can be optimized.

[0183] From the perspective of performing ultraviolet irradiation in a gas environment with low oxygen concentration, it is preferable to perform ultraviolet irradiation of the intermediate layer in an inert gas environment. The type of inert gas and the ultraviolet irradiation conditions in an inert gas environment can be defined as the same as those described in the aforementioned item [2.1.2. Process (b1-2): Vacuum ultraviolet irradiation].

[0184] [2.3. Process (c): Formation of polysiloxane sealing layer]

[0185] In this embodiment, a step of forming a polysiloxane sealing layer may also be included. As a method for forming the polysiloxane sealing layer, an example is the method of irradiating the layer with ultraviolet light after forming a layer containing a polysilazane compound. For example, the ultraviolet irradiation conditions may be set to be the same as the ultraviolet irradiation conditions for the intermediate layer described in [2.2.2. Step (b2-2): Irradiation of the intermediate layer with ultraviolet light].

[0186] [3. Variations]

[0187] If the manufacturing method of the device structure related to this embodiment has a process in which process (b1) and process (b2) are performed sequentially in process (b), then the number of repetitions and the number of processes for process (b1) and process (b2) are not limited, and can be appropriately adjusted to match the desired layer structure of the sealing layer.

[0188] As such a process, examples include the aforementioned process (b), which includes a process (b3) for forming a first sealing layer, a process (b4) for forming a second sealing layer as an inorganic sealing layer disposed on the aforementioned first sealing layer, and a process (b5) for forming a third sealing layer as an organic sealing layer disposed on the aforementioned second sealing layer, and includes a process of performing the aforementioned process (b4) and the aforementioned process (b5) at least twice, wherein the aforementioned process (b4) is the aforementioned process (b2) and the aforementioned process (b5) is the aforementioned process (b1).

[0189] When forming two or more organic sealing layers and two or more inorganic sealing layers, process (b1) and process (b2) can be performed the same number of times, process (b1) can be more than process (b2), or process (b1) can be less than process (b2).

[0190] In Figures 2 to 6 described above, although an example of forming a polysiloxane sealing layer as the first sealing layer has been shown, an organic sealing layer may also be formed as the first sealing layer.

[0191] Furthermore, although not shown in the figure, for example, an inorganic sealing layer can be formed after an organic sealing layer is formed on the component part to form a two-layer sealing layer.

[0192] For example, the manufacturing method of the device structure may also include a step of forming an arbitrary layer. Accordingly, the manufacturing method of the device structure may also include a step of forming an arbitrary layer between the element portion and the sealing layer. Furthermore, the manufacturing method of the device structure may also include a step of forming an arbitrary layer covering the sealing portion. To give a specific example, in the case of a display device in which the device structure system includes an organic electroluminescent element portion, the manufacturing method of this device structure may also include a step of providing a layer of a circular polarizing plate on the sealing layer as needed using an intermediate adhesive.

[0193] In the manufacturing method described above, either the step (b1) of forming the organic sealing layer 210 or the step (b2) of forming the inorganic sealing layer 220 can be performed under atmospheric pressure. Accordingly, since large and complex manufacturing equipment is not required, the device structure 10 can be manufactured at low cost. Furthermore, especially when the organic intermediate layer and intermediate body layer are formed by coating, since the layer can be formed in a wet process, the deterioration of the component caused by particles such as plasma dust can be suppressed.

[0194] 『Example』

[0195] The following embodiments are disclosed to specifically illustrate the present invention. However, the present invention is not limited to the embodiments disclosed below, and may be implemented in any way without departing from the scope of the claims and their equivalents.

[0196] In the following description, the terms "%" and "parts" are by weight unless otherwise noted. Furthermore, the operations described below are performed at normal temperature and pressure unless otherwise noted.

[0197] [Evaluation Method]

[0198] [Young's coefficient, tensile elongation and tanδ of resin]

[0199] The Young's coefficient and elongation at 23°C were measured in accordance with JIS K7113. The loss tangent (tanδ) of the resin at temperatures above 40°C and below 200°C was measured using a Hitachi Advanced Technology Corporation DMS6100 dynamic viscoelasticity measuring device after the resin was made into a film and cut into test pieces with a width of 10 mm and a length of 20 mm.

[0200] [Evaluation of sealing performance under high temperature and high humidity environment]

[0201] The aforementioned device structure was left to stand in a test environment of 60°C and 90%RH. After 0 hours, 24.5 hours, 138 hours, 210 hours, and 284.5 hours, the luminescent surface was observed using a microscope to observe the presence or absence of the color-changing portion. Furthermore, the shrinkage was measured after 0 hours, 24.5 hours, 138 hours, 210 hours, 284.5 hours, and 500 hours. Shrinkage is defined as the length of the non-luminescent portion measured from the end of the initial luminescent portion after a specified time.

[0202] [Manufacturing Example 1: Manufacturing of modified products of hydrogenated aromatic ethylene compounds-conjugated diene block copolymers due to silicon-containing polar groups]

[0203] (P1-1. Preparation of hydrogenated block copolymer)

[0204] Using styrene as an aromatic ethylene compound and isoprene as a chain conjugated diene compound, a hydrogenated block copolymer (hydrogenated block copolymer) having a triblock structure in which polymer blocks [A] are bonded to both ends of polymer blocks [B] is manufactured through the following process.

[0205] In a reactor equipped with a stirring device and thoroughly nitrogen-purified internally, 256 parts of dehydrated cyclohexane, 25.0 parts of dehydrated styrene, and 0.615 parts of di-n-butyl ether were placed in the reactor. While stirring at 60°C, 1.35 parts of n-butyllithium (15% cyclohexane solution) were added to initiate polymerization. The reaction was then carried out at 60°C for 60 minutes with continued stirring. The polymerization conversion rate at this point was 99.5% (polymerization conversion rate was measured by gas chromatography. The same applies below).

[0206] Next, 50.0 parts of dehydrated isoprene were added, and the mixture was stirred continuously at the same temperature for 30 minutes. The polymerization conversion rate at this point was 99%.

[0207] After that, 25.0 parts of dehydrated styrene were added, and the mixture was stirred at the same temperature for 60 minutes. At this point, the polymerization conversion rate was almost 100%.

[0208] Subsequently, 0.5 parts of isopropanol were added to the reaction solution to stop the reaction and obtain a solution (i) containing the block copolymer.

[0209] The weight-average molecular weight (Mw) of the block copolymer in the obtained solution (i) was 44,900, and the molecular weight distribution (Mw / Mn) was 1.03 (measured by gel permeation chromatography using tetrahydrofuran as the solvent, converted to polystyrene values. The same applies below).

[0210] Next, solution (i) was transferred to a pressure reactor equipped with a stirring device. 4.0 parts of a silica-alumina supported nickel catalyst (E22U, nickel loading 60%; manufactured by Nichih Chemical Co., Ltd.) and 350 parts of dehydrated cyclohexane were added to solution (i) as hydrogenation catalysts and mixed. The reactor was purged with hydrogen, and hydrogen was supplied while the solution was stirred. The hydrogenation reaction was carried out for 6 hours at a temperature of 170°C and a pressure of 4.5 MPa, thereby hydrogenating the block copolymer to obtain a solution (iii) containing hydride (ii) of the block copolymer. The weight-average molecular weight (Mw) of hydride (ii) in solution (iii) was 45,100, and the molecular weight distribution (Mw / Mn) was 1.04.

[0211] After the hydrogenation reaction is completed, solution (iii) is filtered to remove the hydrogenation catalyst. Then, 1.0 part of xylene solution containing 0.1 part of 6-[3-(3-tert-butyl-4-hydroxy-5-methylphenyl)propoxy]-2,4,8,10-tetra(tert-butyl)diphenyl[d,f][1,3,2]phosphine dioxane (SUMILIZER GP, manufactured by Sumitomo Chemical Co., Ltd., hereinafter referred to as "antioxidant A") is added to the filtered solution (iii) and dissolved to obtain solution (iv).

[0212] Subsequently, the solution (iv) was filtered using a Zeta Plus (registered trademark) filter 30H (manufactured by CUNO Corporation, pore size 0.5 μm to 1 μm), and further filtered sequentially using another metal fiber filter (pore size 0.4 μm, manufactured by NICHIDAI Corporation) to remove minute solid components. From the filtered solution (iv), cyclohexane, xylene, and other volatile components that serve as solvents were removed using a cylindrical concentrator (product name "KONTRO", manufactured by Hitachi, Ltd.) at a temperature of 260°C and a pressure of 0.001 MPa or less. Then, the solid components were extruded into strands in a molten state from a mold directly connected to the aforementioned concentrator and cooled, and then cut into granules (v) containing the hydride of the block copolymer and antioxidant A using a granulator. The obtained particles (v) contain hydrides of block copolymers (hydrogenated block copolymers) with a weight-average molecular weight (Mw) of 45,000 and a molecular weight distribution (Mw / Mn) of 1.08. Furthermore, the hydrogenation rate, as measured by 1H-NMR, is 99.9%.

[0213] (P1-2. Manufacturing of silane-modified hydrogenated block copolymers)

[0214] For 100 parts of granules (v) obtained in the aforementioned process (P1-1), 2.0 parts of vinyltrimethoxysilane and 0.2 parts of di(tributyl) peroxide were added to obtain a mixture. This mixture was kneaded using a biaxial extruder at a barrel temperature of 210°C and a residence time of 80 to 90 seconds. The kneaded mixture was extruded and cut by a granulator to obtain granules (vi) of the silane-modified hydrogenated block copolymer. Film-shaped test pieces were made from these granules (vi), and the glass transition temperature Tg was evaluated using a dynamic viscoelasticity measuring device with a tanδ peak value, which was 124°C. Furthermore, the peak value of tanδ for this granule (vi) between 40°C and 200°C was 1.3. The Young's coefficient of this granule (vi) at 23°C was 0.5 GPa, and the elongation at break was 550%. Furthermore, the refractive index (n1) of this particle (vi) measured by Abbe refractometer is 1.50.

[0215] [Manufacturing Example 2: Manufacturing of a resin composition for forming an organic sealing layer]

[0216] (P2-1. Preparation of hygroscopic particle dispersion)

[0217] Using a bead mill, 10 g of zeolite particles with a primary particle size of 50 nm (refractive index 1.5), 4 g of a dispersant with alkaline adsorption groups (containing hydroxycarboxylic acid ester, trade name "DISPERBYK108", manufactured by BYK-Chemie), and 46 g of cyclohexane were mixed and dispersed. A 17% zeolite dispersion 1 was prepared by this operation.

[0218] (P2-2. Preparation of polymer solution)

[0219] 28 g of the granules (vi) obtained in Manufacturing Example 1 and 12 g of plasticizer (a plasticizer containing an aliphatic hydrocarbon polymer, product name "Nippon Oil Polybutene LV-100", manufactured by Nippon Oil Co., Ltd., refractive index 1.50, quantity average molecular weight 500) were mixed with 60 g of cyclohexane and dissolved. A polymer solution 1 with a solid content of 40% was prepared by this operation.

[0220] (P2-3. Manufacturing of resin composition)

[0221] 60 g of the zeolite dispersion 1 obtained in the aforementioned step (P2-1) and 100 g of the polymer solution 1 obtained in the aforementioned step (P2-2) were mixed to obtain a resin solution 1 as a resin component. The viscosity of the obtained resin solution 1 was measured. Viscosity was measured using a tuning fork type vibratory viscometer "SV-10" manufactured by A&D Corporation. The measurement was performed by filling the container with the resin solution 1 between the liquid level and the baseline of the sample container, and placing the vibrator in the resin solution to the specified position. This measurement was conducted at an environment of 25°C ± 2°C. The resulting viscosity of the resin solution 1 was 400 cP.

[0222] [Manufacturing Example 3: Manufacturing of Liquid Components of Polysiloxane Sealing Layer (PDMS Layer)]

[0223] A solution of X-34-4184-A, X-34-4184-B and D5 KF-995 manufactured by Shin-Etsu Chemical Co., Ltd. was mixed in a weight ratio of X-34-4184-A:X-34-4184-B:D5 KF-995 = 1:1:16 to prepare a liquid composition for PDMS layer.

[0224] [Manufacturing Example 4: Preparation of Liquid Composition for Inorganic Sealing Layers]

[0225] PHPS X-45-850 (20 wt% dibutyl ether solution) manufactured by Shin-Etsu Chemical Co., Ltd. and dibutyl ether (DBE) were mixed in a weight ratio of PHPS X-45-850:DBE = 1:1 to prepare a liquid composition.

[0226] [Manufacturing Example 5: Manufacturing of a multilayer material having an organic electroluminescent element portion]

[0227] Prepare a glass substrate with a length of 40 mm and a width of 40 mm. Sequentially form a transparent electrode layer with a thickness of 100 nm, a hole transport layer with a thickness of 10 nm, a yellow light-emitting layer with a thickness of 20 nm, an electron transport layer with a thickness of 15 nm, an electron injection layer with a thickness of 1 nm, and a reflective electrode layer with a thickness of 100 nm on the glass substrate.

[0228] From the hole transport layer to the electron transport layer, all are formed of organic materials. The materials used to form each layer from the transparent electrode layer to the reflective electrode layer are as follows: • Transparent electrode layer: Indium tin oxide (ITO) • Hole transport layer: 4,4′-bis(N-naphthyl-N-phenylamino)biphenyl (α-NPD) • Yellow luminescent layer: α-NPD with 1.5% by weight of red fluorene • Electron transport layer: BCP (Byrholine derivative) • Electron injection layer: Lithium fluoride (LiF) • Reflective electrode layer: Al

[0229] The transparent electrode layer is formed by reactive sputtering using an ITO target.

[0230] Furthermore, the formation of the hole transport layer to the reflective electrode layer is carried out by placing a substrate with a transparent electrode layer already formed in a vacuum evaporation apparatus, and then sequentially evaporating the materials from the hole transport layer to the reflective electrode layer by resistance heating.

[0231] Through the above operations, a multilayer material is obtained having a glass substrate and an organic electroluminescent element having a transparent electrode layer, a hole transport layer, a yellow light-emitting layer, an electron transport layer, an electron injection layer and a reflective electrode layer in sequence.

[0232] [Example]

[0233] The liquid composition used for the PDMS layer obtained in Manufacturing Example 3 was coated and dried by spin coating (conditions: 1 mL drop volume, 6000 rpm, 30 seconds) using a method that covers the organic electroluminescent element portion of the coating prepared in Manufacturing Example 5. Then, the PDMS layer was cured by UV (365 nm) irradiation at 12 mW / cm² for 200 seconds. Afterwards, the PDMS layer was irradiated with VUV (172 nm) at 55 mW / cm² for 130 seconds in an N₂ gas environment. Through the above procedures, a PDMS layer (first sealing layer) with a thickness of approximately 170 nm was obtained.

[0234] Next, the liquid composition used to manufacture the inorganic sealing layer of Example 4 was coated by spin coating (conditions: 1 mL drop, 6000 rpm, 30 seconds) and dried. Then, it was irradiated with VUV (172 nm) at 55 mW / cm2 for 220 seconds in an N2 atmosphere. Through the above procedure, an inorganic sealing layer (second sealing layer) with a thickness of 130 nm was obtained. This process is consistent with process (b2).

[0235] Next, the resin composition obtained in Manufacturing Example 2 is coated by spin coating (conditions: 1 mL drop volume, 6000 rpm, 60 seconds) and dried to form an organic intermediate layer. Subsequently, the organic intermediate layer is irradiated with VUV (172 nm) at 55 mW / cm² for 220 seconds in an N₂ atmosphere. Afterward, oxygen is introduced into the system until the O₂ concentration reaches 5%, and VUV (172 nm) is irradiated with VUV (172 nm) at 55 mW / cm² for 220 seconds in a mixed N₂ and O₂ atmosphere. Through the following procedure, an organic sealing layer (third sealing layer) with a thickness of 100 nm is obtained. This process is consistent with process (b1).

[0236] Next, repeat steps (b2) and (b1) to create the sealing layer with a 7-layer structure shown in Figure 1. The device structure is obtained through the above procedures.

[0237] Furthermore, the resin composition obtained in Manufacturing Example 2 was coated onto a silicon substrate to form an organic sealing layer, similar to the third sealing layer. Under a nitrogen atmosphere, the sample was irradiated with VUV (172 nm) at an illuminance of 30 mW / cm² for 3 minutes at 23°C–25°C and 50%–60% humidity to obtain a sample. The thickness T1 of the obtained sample's organic sealing layer was measured, and the sample was then immersed in dibutyl ether for 60 seconds and allowed to air dry. The thickness T2 of the organic sealing layer in the air-dried sample was measured. The residual film rate of the organic sealing layer in the dibutyl ether dissolution test was calculated from the measured values ​​of T1 and T2, and the result was 97%.

[0238] [Comparative Example]

[0239] In a comparative embodiment, a PDMS layer and an inorganic sealing layer are fabricated on the organic electroluminescent element portion of the coated material. Next, by repeating the same procedure as the first PDMS layer, a third PDMS layer is formed on the second inorganic sealing layer. Then, by repeating the same procedure as the second inorganic sealing layer and the first PDMS layer, the inorganic sealing layer and the PDMS layer are further stacked alternately in pairs to fabricate a sealing layer with a 7-layer structure. The device structure is obtained through the above procedures.

[0240] [Result]

[0241] Figure 7 shows photographs of the luminescent surface in the evaluation of sealing performance under high temperature and high humidity conditions, and Figure 8 shows a graph of the change in shrinkage value relative to time. As shown in Figures 7 and 8, in the embodiments including the organic sealing layer and the inorganic sealing layer related to this embodiment, no discoloration was observed on the luminescent surface after 284.5 hours, and the change in shrinkage was also small, confirming its good sealing performance. On the other hand, in the comparative example, an increase in discoloration points was gradually observed starting after 138 hours, and an increase in shrinkage was also observed.

[0242] [Reference Example]

[0243] The resin composition obtained in Manufacturing Example 2 was coated onto a silicon substrate and heated at 100°C for 1 minute to form an organic layer with a thickness of 120 nm. Under a nitrogen atmosphere, the organic layer was irradiated with VUV (172 nm) at an illuminance of 30 mW / cm². The FT-IR spectra before and after irradiation were measured, confirming that the peak intensity at 2925 cm⁻¹ decreased before and after VUV irradiation. Furthermore, by investigating the correlation between the ratio of I2 to I1 when the irradiation time was adjusted and the peak intensity before VUV irradiation was defined as I1 and the peak intensity after irradiation as I2, and the residual film rate in the dibutyl ether dissolution test, it was confirmed that the residual film rate of the organic layer with an I2 / I1 ratio of 50% or less was 90% or more. In the FT-IR spectrum, the peak at 2925 cm⁻¹ originates from the C-H stretching vibration.

[0244] In the reference example, the VUV irradiation time and residual film yield are as follows: • Irradiation time 1 minute, residual film yield 80% • Irradiation time 3 minutes, residual film yield 97% • Irradiation time 5 minutes, residual film yield 100% [Simplified Explanation of the Diagram]

[0024] 〈Figure 1〉: Figure 1 is a schematic cross-sectional view of a device structure related to one embodiment of the present invention.

[0025] 〈Fig. 2〉: Fig. 2 is a cross-sectional schematic diagram of the preparation of a multilayer material in step (a) of the manufacturing method of a device structure related to one embodiment of the present invention.

[0026] 〈Fig. 3〉: Fig. 3 is a cross-sectional schematic diagram showing the state in step (b) of the manufacturing method of the device structure related to one embodiment of the present invention, in which a first sealing layer for sealing the component part is formed on the cover.

[0027] 〈Fig. 4〉: Fig. 4 is a cross-sectional schematic diagram showing the state in which a second sealing layer as an inorganic sealing layer is formed on a cover in step (b) of a method for manufacturing a device structure related to one embodiment of the present invention.

[0028] 〈Fig. 5〉: Fig. 5 is a cross-sectional schematic diagram showing the state in which a third sealing layer as an organic sealing layer is formed on a coating in step (b) of a method for manufacturing a device structure related to one embodiment of the present invention.

[0029] 〈Fig. 6〉: Fig. 6 is a cross-sectional schematic diagram showing a second sealing layer as an inorganic sealing layer and a third sealing layer as an organic sealing layer being alternately formed on a coating in step (b) of a method for manufacturing a device structure related to one embodiment of the present invention.

[0030] 〈Fig. 7〉: Fig. 7 is a table showing the results of microscopic observation of the embodiments and comparative examples.

[0031] 〈Figure 8〉: Figure 8 is a graph illustrating the changes in shrinkage of the embodiment and the comparative example.

Claims

1. A device structure comprising a multilayer having a substrate and an element portion disposed on the substrate, and a sealing layer sealing the element portion, wherein the sealing layer has a structure in which an organic sealing layer and an inorganic sealing layer are sequentially stacked relative to the element portion, the organic sealing layer being formed directly or through other layers on the surface of the element portion, the inorganic sealing layer being stacked on the organic sealing layer, the inorganic sealing layer comprising silicon nitride, the organic sealing layer comprising a thermoplastic elastomer, and in a dissolution test for dibutyl ether, the residual film rate of the organic sealing layer being 90% or more, the thermoplastic elastomer being a modified product of a hydrogenated aromatic ethylene compound-conjugated diene block copolymer caused by silicon-containing polar groups.

2. The device structure as described in claim 1, wherein the aforementioned sealing layer includes a first sealing layer disposed on the aforementioned component portion and two or more second sealing layers and two or more third sealing layers disposed on the aforementioned first sealing layer, and has a structure in which the aforementioned second sealing layer and the aforementioned third sealing layer are stacked alternately, wherein the aforementioned second sealing layer is the aforementioned inorganic sealing layer and the aforementioned third sealing layer is the aforementioned organic sealing layer.

3. The device structure as described in claim 2, wherein the aforementioned first sealing layer is the aforementioned organic sealing layer or a polysiloxane sealing layer comprising polysiloxane.

4. The device structure as claimed in claim 1 or 2, wherein the aforementioned hydrogenated aromatic ethylene compound-conjugated diene block copolymer has a structure in which both non-aromatic carbon-carbon unsaturated bonds and aromatic carbon-carbon unsaturated bonds are hydrogenated.

5. The device structure as claimed in claim 1 or 2, wherein the aforementioned organic sealing layer comprises one or more of the group consisting of hygroscopic particles and ultraviolet absorbers.

6. The device structure as described in claim 1 or 2, wherein the thickness of each structural layer included in the aforementioned sealing layer is less than 300 nm.

7. The device structure as described in claim 1 or 2, wherein the aforementioned element portion is an organic electroluminescent element portion.

8. A method for manufacturing a device structure, comprising a step (a) of preparing a multilayer having a substrate and a component portion disposed on the substrate, and a step (b) of forming a sealing layer sealing the component portion, wherein the step (b) of forming the sealing layer includes a step (b1) of forming an organic sealing layer and a step (b2) of forming an inorganic sealing layer after step (b1), wherein the step (b1) includes a step (b1-1) of forming an organic intermediate layer including a thermoplastic elastomer and a step (b1-2) of irradiating the organic intermediate layer with vacuum ultraviolet light to obtain the organic sealing layer. Step (b2) includes step (b2-1) of forming an intermediate layer using a liquid composition containing a polysilazane compound and a solvent, and step (b2-2) of irradiating the aforementioned intermediate layer with ultraviolet light to obtain an inorganic sealing layer containing silicon nitride; in the aforementioned step (b2-1), the aforementioned liquid composition contains dibutyl ether as the aforementioned solvent, and in step (b1-2), the aforementioned organic sealing layer is obtained. In the dissolution test of the aforementioned dibutyl ether, the residual film rate of the aforementioned organic sealing layer is more than 90%, and the aforementioned thermoplastic elastic system hydrogenated aromatic ethylene compound-conjugated diene block copolymer is modified by silicon-containing polar groups.

9. A method for manufacturing a device structure as claimed in claim 8, wherein the aforementioned step (b1-2) includes a step (b1-2-1) of irradiating the aforementioned organic intermediate layer with vacuum ultraviolet light in an inert gas environment and a step (b1-2-2) of irradiating the aforementioned organic intermediate layer after the aforementioned step (b1-2-1) with vacuum ultraviolet light in a mixed gas environment of inert gas and oxygen.

10. A method for manufacturing a device structure as claimed in claim 8 or 9, wherein the aforementioned step (b) comprises: a step (b3) of forming a first sealing layer, a step (b4) of forming a second sealing layer as an inorganic sealing layer disposed on the aforementioned first sealing layer, and a step (b5) of forming a third sealing layer as an organic sealing layer disposed on the aforementioned second sealing layer, and includes a step of performing the aforementioned step (b4) and the aforementioned step (b5) at least twice, wherein the aforementioned step (b4) is the aforementioned step (b2), and the aforementioned step (b5) is the aforementioned step (b1).

11. The method for manufacturing the device structure as claimed in claim 10, wherein the aforementioned step (b3) is the aforementioned step (b1), which is the step of forming the aforementioned first sealing layer as the aforementioned organic sealing layer.

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