Sealing layer forming sheet and member sealed with multiple light emitting elements

Abstract

The present application provides a sealing layer forming sheet and a member having multiple light emitting elements sealed therein, which has excellent resistance to migration and invisibility of the boundary. The sealing layer forming sheet of the present disclosure is a sealing layer forming sheet (1) for embedding light emitting elements (7) for a display using multiple light emitting elements (7) as light sources, and covering the multiple light emitting elements (7), and the sealing layer forming sheet (1) is sequentially provided with a first film (2), a sealing layer precursor (a), and a second film (5), the sealing layer precursor (a) has a water vapor permeability of less than 100 [g / (m 2 ·24 hours)], a moisture absorption rate of 1.5% or less by mass, and a refractive index of 1.51 ± 0.03 for a colorless resin composition layer (3) for embedding and a refractive index of 1.53 ± 0.03 for a water vapor barrier layer (4).

Description

Technical Field

[0001] This disclosure relates to a sealing layer forming sheet and a component sealing multiple light-emitting elements. More specifically, it relates to a sealing layer forming sheet suitable for sealing multiple microLED elements, and a component sealing multiple microLED elements. Background Technology

[0002] In recent years, there has been active development regarding displays, with the goal of further increasing performance, using various light-emitting elements.

[0003] Specifically, the study investigated various display specifications, including backlit displays using liquid crystals or quantum dots, displays using self-emissive elements such as mini / micro light-emitting diodes (LEDs) or organic electroluminescence (EL), plasma displays, and electrophoretic displays. The research covered a wide range of applications, from large displays exceeding 40 or 50 units (such as signage or televisions) to smaller applications such as tablets, personal computers, smartphones, and wearable devices. In particular, the development of LED-based displays has progressed significantly, with sealing sheets for sealing multiple LED elements proposed and described in Patent Documents 1 through 4 (e.g., Japanese Patent Application Laid-Open No. 2023-12051, International Publication No. 2021 / 200035, International Publication No. 2021 / 245830, and International Publication No. 2022 / 145399). Summary of the Invention

[0004] [The problem the invention aims to solve]

[0005] In recent years, with the miniaturization of LED components, especially micro-sized LED components, if the spacing or distance between LED components becomes narrower, there is a problem that the finer and denser circuits are prone to corrosion due to water vapor or ion precipitation (hereinafter also referred to as migration).

[0006] In addition, since a display is formed by assembling and arranging a large number of components that are sealed with multiple light-emitting elements, there is a problem that the boundaries between the components can be seen, which reduces the display performance of the display.

[0007] This disclosure is made in view of the aforementioned problems, and its objective is to provide a sealing layer forming sheet for sealing micro-LED elements, which has excellent embeddability and water vapor barrier properties, excellent invisibility of the boundary between layers in a colorless sealing layer, and excellent invisibility of the boundary between the transparent substrate and the colorless sealing layer when the colorless sealing layer is stacked directly above a transparent substrate, and a component of a sealing layer having excellent migration resistance and excellent invisibility of the boundary.

[0008] [Technical means to solve the problem]

[0009] The inventors and others have conducted intensive research and have found that microLED components that solve the aforementioned problems can be manufactured with high quality and efficiency using the sealing layer forming sheet shown below, thereby completing the present disclosure as described below [1] to [7].

[0010] [1]: A sealing layer forming sheet for burying the light-emitting elements of a display that uses multiple light-emitting elements as light sources between each other, and covering the side of the surface from which the light of the multiple light-emitting elements is emitted.

[0011] The sealing layer forming sheet is sequentially configured with a first membrane 2, a sealing layer precursor α, and a second membrane 5.

[0012] The water vapor permeability of the sealing layer precursor α is less than 100 g / (m 2 [24 hours], moisture absorption rate is less than 1.5% by mass.

[0013] The sealing layer precursor α has a refractive index of 1.51 ± 0.03 and a water vapor permeability of 100 g / (m 2 • 24 hours) or more of colorless resin composition layer 3 for embedding, and a refractive index of 1.53 ± 0.03 and a water vapor transmission rate of less than 100 g / (m 2 Water vapor barrier layer 4 (24 hours)

[0014] [2]: The sealing layer forming sheet according to [1], wherein the water vapor barrier layer 4 is a thermoplastic olefin film.

[0015] [3]: The sealing layer forming sheet according to [1] or [2], wherein the tensile storage elastic modulus E'3 (100) of the colorless resin composition layer 3 for embedding at 100°C, the tensile storage elastic modulus E'4 (100) of the water vapor barrier layer 4, and the tensile storage elastic modulus E'5 (100) of the second film 5 satisfy the following relationship.

[0016] E'4(100) / E'3(100) is between 100 and 1000, and

[0017] E'5(100) / E'4(100) is 0.5 to 3.

[0018] [4]: A sheet for forming a sealing layer according to any one of [1] to [3], wherein the total light transmittance of the sealing layer precursor α is 85% or more.

[0019] [5]: A component sealed with a plurality of light-emitting elements, having a substrate and a plurality of light-emitting elements spaced apart and mounted on the substrate.

[0020] At least a portion of the depth direction of the gaps between the light-emitting elements is composed of a refractive index of 1.51 ± 0.03 and a water vapor transmittance of 100 g / (m²). 2 The hardened material 3' of the colorless resin composition layer 3 for embedding (24 hours or more) is embedded.

[0021] One side emitting light from multiple light-emitting elements is sequentially embedded with a hardened layer 3' of a colorless resin composition layer 3 and a layer with a refractive index of 1.53 ± 0.03 and a water vapor transmittance of less than 100 g / (m²). 2 Water vapor barrier layer 4 covering (24 hours)

[0022] [6]: The component sealed with a plurality of light-emitting elements according to [5], wherein at least a portion of the depth direction of the gaps between the light-emitting elements and / or at least a portion of the bottom surface of the gaps are embedded by a hardened layer 9' of the colored resin composition 9 for embedding, and the remaining portions of the gaps between the light-emitting elements are embedded by a hardened layer 3' of the colorless resin composition layer 3 for embedding.

[0023] [7]: A component sealed with multiple light-emitting elements according to [5] or [6], wherein the water vapor barrier layer 4 is a thermoplastic olefin film.

[0024] [The effects of the invention]

[0025] The present disclosure provides the following excellent effects: it provides a sealing layer forming sheet for sealing microLED elements, which has excellent embeddability and water vapor barrier properties, excellent invisibility of the boundary between layers in the colorless sealing layer, and excellent invisibility of the boundary between the transparent substrate and the colorless sealing layer when the colorless sealing layer is stacked directly above a transparent substrate, and a component of a sealing layer with excellent migration resistance and excellent invisibility of the boundary can be provided. Attached Figure Description

[0026] Figure 1 (1) Figure 1 (2) is a schematic cross-sectional view of the sealing layer forming sheet of this disclosure.

[0027] Figure 2(1)~ Figure 2 (5) is a schematic cross-sectional view for illustrating the gap state of the light-emitting elements in a component of the present disclosure that is sealed with multiple light-emitting elements.

[0028] Figure 3 (1) Figure 3 (2) is a schematic cross-sectional view used to illustrate the thickness of each layer in the component of the present disclosure that is sealed with multiple light-emitting elements.

[0029] Figure 4 (I-1) Figure 4 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0030] Figure 5 (I-1) Figure 5 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0031] Figure 6 (I-1) Figure 6 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0032] Figure 7 (I-1) Figure 7 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0033] Figure 8 (I-1) Figure 8 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0034] Figure 9 (I-1) Figure 9 (VII) is a schematic cross-sectional view illustrating the process of manufacturing a component of the present disclosure that is sealed with multiple light-emitting elements by using a sealing layer forming sheet of the present disclosure to seal multiple light-emitting elements.

[0035] Figure 10 (1-a)~ Figure 10(3-d) is a schematic cross-sectional view used to illustrate the process of preparing sealing objects β2 and β3.

[0036] Figure 11 (1) Figure 11 (2) is a schematic diagram used to illustrate the evaluation of the invisibility of the boundary portion, etc. of the LED sealing member model in the embodiment.

[0037] Explanation of icon numbers

[0038] 1: Sheet for forming sealing layer

[0039] 2: First membrane

[0040] 3: Colorless resin composition layer for embedding

[0041] 3': Cured product of the colorless resin composition layer for embedding

[0042] 4: Water vapor barrier layer

[0043] 5: Second membrane

[0044] 6: Substrate

[0045] 7: Light-emitting element

[0046] 8: A component sealed with multiple light-emitting elements

[0047] 9: Colored resin composition for embedding

[0048] 9': Cured product of colored resin composition for embedding

[0049] 11: Peel-off membrane

[0050] T1, T2: Thickness

[0051] α: Precursor to sealing layer

[0052] β1, β2, β3: Sealed objects Detailed Implementation

[0053] The present disclosure will now be described in detail. Furthermore, the embodiments described below are examples of the present disclosure. The present disclosure is not limited to the following embodiments, and also includes variations implemented within the scope of the present disclosure.

[0054] In this specification, the numerical range specified by “~” includes the values ​​stated before and after “~” as the lower and upper limits. (Meth)acrylic acid refers to acrylic acid and / or methacrylic acid. Furthermore, unless otherwise specified, each ingredient appearing in this specification may be used independently or in combination with two or more ingredients. In addition, when two or more ingredients are used together, the total content value is used.

[0055] • [Sealing layer forming sheet]

[0056] The sealing layer forming sheet 1 disclosed herein is a sheet for forming a sealing member for a display. More specifically, the sealing layer forming sheet 1 is a sheet for forming a sealing layer that fills the space between light-emitting elements in a display that uses multiple light-emitting elements as a light source, and covers the side of the surface from which light is emitted from the multiple light-emitting elements. Here, the side that emits light has the same meaning as the side where the light-emitting elements are disposed. That is, the sealing layer forming sheet 1 is a sheet for covering at least a portion of the substrate and the light-emitting elements.

[0057] A sealed light-emitting component (hereinafter referred to as a "component") is a component having at least a substrate, light-emitting elements, and a sealing layer, wherein multiple light-emitting elements (such as micro LED elements) are disposed on a substrate and these light-emitting elements are sealed by a sealing layer.

[0058] like Figure 1 As shown in (1), the sealing layer forming sheet 1 is sequentially provided with a first film 2, a sealing layer precursor α, and a second film 5. The sealing layer precursor α has an embedding colorless resin composition layer 3 and a water vapor barrier layer 4.

[0059] ·<Seal Precursor α>

[0060] Importantly, the water vapor permeability of the sealing layer precursor α is less than 100 g / (m 2 The moisture absorption rate is less than 1.5% by mass (24 hours). The water vapor permeability is preferably 70 g / (m²). 2 ·24 hours) or less, more preferably 50 [g / (m 2 ·24 hours) or less, and more preferably 30 [g / (m 2 ·24 hours) or less, particularly preferably 10 [g / (m 2 • 24 hours or less. The moisture absorption rate is preferably 1% by mass or less, more preferably 0.8% by mass or less. Water vapor permeability refers to the speed at which water vapor moves, while moisture absorption rate refers to the ability to store water vapor. By minimizing water vapor permeability or moisture absorption rate, water vapor is less likely to pass through or be contained, thus improving the migration resistance of the sealed component. Improved migration resistance further expands the possibilities for using displays in high-temperature and high-humidity environments.

[0061] Water vapor transmission rate refers to the measurement using a Labthink water vapor transmission rate measuring device: C390H (based on International Standardization Organization (ISO) 15106-2 and American Society for Testing and Materials (ASTM) F1249), with a transmission area of ​​5 cm². 2 Under the conditions of 40℃ × 90% RH, the values ​​obtained after approximately 24 hours are [g / (m 2 • 24 hours). In addition, the measured value remained unchanged, but the surface in contact with water vapor during the measurement was taken as the surface of the colorless resin composition layer.

[0062] Regarding moisture absorption rate, 10cm 2 After measuring the mass of the sample in an environment of 23°C and 50%RH, the sample was left to stand for 24 hours in an environment of 40°C and 90%RH to absorb moisture. Then, the sample was returned to an environment of 23°C and 50%RH and the mass of the sample was measured within 1 hour. The rate of change of mass calculated based on the following formula was taken as the moisture absorption rate.

[0063] Moisture absorption rate (%) = [(Value after moisture absorption ÷ Value before moisture absorption) - 1] × 100

[0064] The thickness of the sealing layer precursor α is preferably 10 μm to 100 μm, more preferably 12 μm to 50 μm, and particularly preferably 15 μm to 30 μm. A thickness of 10 μm or more improves water vapor barrier properties, while a thickness of 100 μm or less maintains a high level of transparency. By setting the thickness within this particularly preferred range, a display can be obtained that simultaneously achieves a high level of water vapor barrier properties, improved transparency, and excellent color rendering and display performance.

[0065] • <Insertion layer 3: Colorless resin composition for embedding>

[0066] The colorless resin composition layer 3 (hereinafter sometimes simply referred to as the colorless resin composition layer, colorless resin composition layer, or resin composition layer) is used to seal the light-emitting element mounted on the substrate, and importantly, its refractive index is 1.51 ± 0.03, preferably with the refractive index difference from that of the substrate on which the light-emitting element is mounted being as small as possible. The substrate will be described later.

[0067] Furthermore, regarding the display performance of the display, it is important that the colorless resin composition layer 3 for embedding is colorless, or more precisely, colorless and transparent. Specifically, regarding colorlessness, it is important that the b value in the Lab value is 1.5 or less, preferably 1.0 or less. Furthermore, regarding transparency, it is important that the haze is 3.0% or less, preferably 1.0% or less.

[0068] Furthermore, the colorless resin composition layer 3 for embedding is also expected to have excellent water vapor barrier properties. However, it is difficult to balance embedding properties and water vapor barrier properties. In terms of water vapor permeability, compared to the water vapor barrier layer 4 described later, the water vapor permeability is 100 [g / (m 2 (24 hours) or more.

[0069] Furthermore, it is important that the colorless resin composition layer is hydrophobic, and the moisture absorption rate, measured using the same method as the sealing layer precursor α, is preferably 1.5% or less, more preferably 1.0% or less. When the moisture absorption rate exceeds 1.5%, even if water vapor permeability is low and water vapor is difficult to pass through, water vapor is easily absorbed, and the hardened colorless resin composition layer after sealing also easily absorbs water vapor. The hardened colorless resin composition layer is sandwiched between the substrate and the water vapor barrier layer as described later, but it is also important to minimize water vapor absorption during the period before sandwiching. Additionally, it is important to suppress / prevent water vapor absorption from the end face after sandwiching. Due to the absorbed moisture, the hardened colorless resin composition layer is prone to whitening at the interface with the substrate or LED elements, or migration (ion deposition or circuit corrosion) mediated by water. Even a small amount of whitening of the hardened material can significantly impair display performance, especially for transparent displays, which is a fatal flaw. By ensuring that the moisture absorption rate of the colorless resin composition layer is 1.0% or less, the possibility of using the display in high-temperature and high-humidity environments is further expanded.

[0070] From the viewpoint of embeddability, the thickness of the colorless resin composition layer is preferably 5 μm to 50 μm, more preferably 10 μm to 40 μm, and even more preferably 15 μm to 30 μm.

[0071] By setting the thickness of the colorless resin composition layer to 5μm to 50μm, the pressure applied to the colorless resin composition layer 3 for embedding is appropriately dispersed and sufficiently homogenized during the pressing process, thereby improving embedding performance.

[0072] Furthermore, by setting the pressure to 5μm to 50μm, the pressure transmission applied to the colorless resin composition layer during the pressing process described later is controlled, resulting in uniform flow of the colorless resin composition layer and thus good embedding properties.

[0073] The colorless resin composition layer comprises at least a resin (A) and an initiator (C).

[0074] Resin (A) is a substance that functions as an adhesive, bonding and fixing objects together. The colorless resin composition layer 3 for embedding is... Figure 4 In processes (IV) to (V), it contacts the top surface of the microLED element and is embedded along the shape of the sealing object β1. Figure 4 In process (VI), the hardened material 3' of the colorless resin composition layer 3, through curing, functions to fix the hardened material 3' embedded in the colorless resin composition layer 3 to the sealing object β1. Figure 5 (I-1) Figure 8 The same applies to case (VII), in Figure 9 (I-1) Figure 9 In case (VII), the same applies except that there is no process of embedding the colorless resin composition layer along the shape of the sealing object β3.

[0075] Regarding the glass transition point of the colorless resin composition layer, the peak temperature of the loss tangent obtained by dynamic viscoelasticity measurement (tanδ peak temperature) is the temperature at which the tanδ curve reaches its maximum. When there are two or more peaks, it indicates the peak temperature on the lowest temperature side. The tanδ peak temperature is preferably 25℃ to 100℃, more preferably 40℃ to 80℃, and even more preferably 50℃ to 70℃.

[0076] Since the tanδ peak temperature is within the range described above, Figure 4 Although it comes into contact with the sealing object β1 in process (IV), it does not adhere firmly, thus making it easy to remove any misalignment or trapped air. Furthermore, since the preferred range is higher than the operating temperature of the LED (40°C), the resin is less prone to degradation and therefore less likely to yellow.

[0077] Furthermore, the peak tanδ temperature of the colorless resin composition layer can be adjusted according to the type or composition of resin (A). When resin (A) is a (meth)acrylic resin, the peak tanδ temperature can be increased by increasing the content of acrylic monomers that form a homopolymer with a high glass transition temperature (Tg). Conversely, if a decrease in the peak tanδ temperature is desired, the adjustment can be made in the opposite manner. The glass transition temperature (Tg) of the homopolymer in this disclosure can be the value described in Polymer Handbook, 1999, Fourth Edition.

[0078] The loss tangent (tanδ) is the ratio of loss modulus to storage modulus obtained by dynamic viscoelasticity measurement in a tensile mode at a frequency of 10 Hz and a temperature range of -50℃ to 150℃.

[0079] The dynamic viscoelasticity and loss tangent (tanδ) in this disclosure are determined by the method described in the examples below. Furthermore, when the colorless resin composition layer 3 for embedding contains either an initiator (C) or a crosslinking agent, the polymerization / crosslinking reaction is incomplete during the measurement. Additionally, the measurement is preferably performed on a sheet with a thickness of 50 μm or more. If the sheet does not meet this requirement, two sets of sealing sheets without a first film can be prepared. The colorless resin composition layer 3 for embedding is then laminated together using a laminator to create a laminate of a second film / colorless resin composition layer 3 for embedding / second film. The second film on one side of the laminate is then peeled off, and the colorless resin composition layer 3 for embedding of the sealing sheet is repeatedly laminated until a thickness of 50 μm or more is achieved, after which the dynamic viscoelasticity is measured.

[0080] Resin (A) requires excellent embedding properties and transparency for sealing, and various resins can be selected.

[0081] Examples include: (meth)acrylic resin, polyurethane resin or polyurethane urea resin, etc., urethane resin, epoxy resin, maleic acid resin, styrene-maleic acid copolymer, polystyrene resin, polybutadiene resin, polyester resin, condensation polyester resin, addition polyester resin, melamine resin, polycarbonate resin, oxetane resin, phenoxy resin, polyimide resin, polyamide-imide resin, alkyd resin, amino resin, polyamide resin, polylactic acid resin, oxazoline resin, benzoxazine resin, silicone resin, fluororesin, butyral resin, chlorinated polyethylene, chlorinated polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polyvinyl acetate, vinyl resins, rubber resins, cyclized rubber resins, cellulose resins, polyethylene (high-density polyethylene (HDPE), low-density polyethylene (LDPE)), etc. Preferred resins are (meth)acrylic resins, urethane resins, and epoxy resins with excellent embedding properties and transparency, and more preferably (meth)acrylic resins that are not prone to yellowing due to heat or light. Resin (A) may be used alone or in combination of two or more.

[0082] The weight average molecular weight (Mw) of resin (A) is preferably between 10,000 and 1,000,000. More preferably between 30,000 and 300,000, and even more preferably between 50,000 and 150,000. By setting the weight average molecular weight (Mw) of resin (A) to below 1,000,000, it is less prone to gelation and less likely to impair transparency. By setting it to 10,000 or above, the coating strength is improved, and the embedding properties are excellent. By being in a more preferred range, it is less prone to deterioration and yellowing due to heat or light, the moisture absorption rate is reduced, and the quality of the manufactured display is improved.

[0083] Furthermore, the weight-average molecular weight (Mw) is a converted value of polystyrene determined by gel permeation chromatography (GPC). The weight-average molecular weight (Mw) in this disclosure is a value determined by the method described in the examples below.

[0084] Resin (A) is preferably a free radical polymerizable functional group having one or more ions or free radicals generated by heat or light that can be used for polymerization / crosslinking reactions. Examples of free radical polymerizable functional groups include (meth)acryloyl, N-vinyl, vinyl ether, allyl, and unsaturated carboxylic acid groups. The functional group can be appropriately selected based on the reactivity of resin (A) with each other or with the initiator (C) and crosslinking agent described later, and can also be a self-crosslinking functional group.

[0085] [(Meth)acrylic resin]

[0086] (Meth)acrylic resin is a (meth)acrylic copolymer obtained by copolymerizing a monomer containing (meth)acrylic ester monomers, and is a polymer having structural units based on 2 to 20,000 monomers. Suitable examples of (meth)acrylic ester monomers include alkyl (meth)acrylic ester monomers. When a functional group suitable for polymerization / crosslinking reactions is introduced, the (meth)acrylic resin is preferably a (meth)acrylic copolymer obtained by copolymerizing a functionalized monomer with a (meth)acrylic ester monomer.

[0087] (Meth)acrylate alkyl ester monomers are compounds formed by esterifying (meth)acrylic acid and introducing an alkyl or cycloalkyl group. The alkyl or cycloalkyl group can be any of a straight-chain, branched-chain, or cyclic saturated aliphatic hydrocarbon group. From the viewpoint of obtaining excellent hydrophobicity, the straight-chain alkyl group preferably has 4 or more carbon atoms. Specific examples include: methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, etc. The following are examples of methacrylates: isodecyl acrylate, undecyl acrylate, dodecyl acrylate, tridecyl acrylate, tetradecyl acrylate, pentadecyl acrylate, hexadecyl acrylate, heptadecanyl acrylate, octadecyl acrylate, nonadecanyl acrylate, eicosyl acrylate, lauryl acrylate, cyclohexyl acrylate, 4-butylcyclohexyl(meth)acrylate, isobornyl acrylate, etc. Especially preferred is n-butyl acrylate, which exhibits excellent hydrophobicity, a good balance between flexibility and rigidity, and excellent embedding and transparency.

[0088] From the viewpoint of adhesion, the (meth)acrylic resin is preferably a structural unit containing 1% to 100% by mass of a (meth)acrylic alkyl ester monomer derived therefrom, more preferably 20% to 99.5% by mass, and even more preferably 80% to 99% by mass.

[0089] (Meth)acrylic resins are preferably structural units and / or unsaturated bonds derived from monomers containing functional groups.

[0090] Examples of functionalized monomers include carboxyl-containing monomers, hydroxyl-containing monomers, epoxy-containing monomers, and amino-containing monomers. By including functionalized monomers, the cohesiveness of resin (A) or its adhesion to a substrate or circuit is improved. Furthermore, the functional groups of the used functionalized monomers can be used to introduce unsaturated bonds that enable free radical polymerization. Hydroxyl-containing and amino-containing monomers, due to their high hydrophilicity, easily compromise hydrophobicity. Epoxy-containing and carboxyl-containing monomers are preferred as they do not easily affect the hydrophobicity of the colorless resin composition layer.

[0091] Examples of carboxyl-containing monomers include: (meth)acrylic acid, β-carboxyethyl (meth)acrylic acid, p-carboxybenzyl (meth)acrylic acid, carboxypentyl (meth)acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, citraconic acid, and isocrotonic acid. Of these, (meth)acrylic acid is preferred from the viewpoint of adhesion.

[0092] Unsaturated bonds with free radical polymerization can also be introduced by reacting glycidyl methacrylate and other substances with the carboxyl groups in (meth)acrylic resins.

[0093] Examples of hydroxyl-containing monomers include: 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 2-hydroxybutyl methacrylate, 3-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 6-hydroxyhexyl methacrylate, 8-hydroxyoctyl methacrylate, 10-hydroxydecyl methacrylate, 12-hydroxylaurate methacrylate, and (4-hydroxymethylcyclohexyl)meth(meth)acrylate. Among these, 4-hydroxybutyl methacrylate and 2-hydroxyethyl methacrylate are more preferred from the viewpoint of adhesion.

[0094] Unsaturated bonds with free radical polymerization properties can also be introduced by reacting compounds with isocyanate and (meth)acryloyl groups with hydroxyl groups in (meth)acrylic resins.

[0095] Examples of amino-containing monomers include: (meth)acrylate monomethylaminoethyl ester, (meth)acrylate monoethylaminoethyl ester, (meth)acrylate monomethylaminopropyl ester, (meth)acrylate monoethylaminopropyl ester, and other (meth)acrylate monoalkylamino esters.

[0096] For the purpose of introducing unsaturated bonds into (meth)acrylic resins, monomers containing epoxy groups may also be used.

[0097] Examples of epoxy-containing monomers include glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, 3,4-epoxycyclohexyl methyl (meth)acrylate, and 6-methyl-3,4-epoxycyclohexyl methyl (meth)acrylate. Of these, glycidyl (meth)acrylate is preferred from a reactivity point of view.

[0098] After obtaining the (meth)acrylic resin, it is preferable to react the epoxy group derived from an epoxy-containing monomer with the carboxyl group of a carboxyl-containing monomer such as (meth)acrylic acid to introduce unsaturated bonds such as (meth)acryloyl groups into the (meth)acrylic resin. In this case, it is preferable that the number of epoxy groups before the introduction of unsaturated bonds is one or less in a molecule, and that no epoxy groups remain in the resin after the introduction of unsaturated bonds.

[0099] The structural units of (meth)acrylic resin are determined by the proportions of the monomers blended during the manufacture of (meth)acrylic resin. Specifically, when the total amount of the constituent monomers is set to 100% by mass, the structural units derived from functionalized monomers are preferably 0.1% to 20% by mass. A content of 0.1% or more by mass provides cohesive strength, while a content of 20% or less by mass inhibits resin gelation.

[0100] Monomers containing functional groups can be mainly categorized as either carboxyl-containing monomers or hydroxyl-containing monomers. When the functional group-containing monomer is a carboxyl-containing monomer, the preferred concentration is 0.1% to 10% by mass. When the functional group-containing monomer is a hydroxyl-containing monomer, the preferred concentration is 0.1% to 20% by mass. By being within these ranges, resin gelation is suppressed, while cohesion is improved.

[0101] The total amount of structural units derived from functionalized monomers is within the range of 0.1% to 20% by mass, and preferably includes both carboxyl-containing monomers and hydroxyl-containing monomers.

[0102] (Meth)acrylic resins may also contain structural units derived from other monomers capable of copolymerizing with alkyl (meth)acrylates and functionalized monomers. Examples include monomers having alkylene oxides and other vinyl monomers. Examples include methoxyethyl acrylate, methoxydiethylene glycol acrylate, vinyl acetate, vinyl crotonate, and styrene. The structural units derived from these other monomers are preferably 0.1% to 20% by mass in 100% by mass of the (meth)acrylic resin.

[0103] (Meth)acrylic resin can be obtained by polymerizing a mixture of acrylic monomers. A polymerization initiator may be used during polymerization as needed. The content of the polymerization initiator is set to, for example, 0.01% to 10% by mass relative to 100% by mass of the monomer mixture. The polymerization method is not limited. For example, polymerization can be carried out by solution polymerization, bulk polymerization, emulsion polymerization, or suspension polymerization; solution polymerization is particularly preferred in terms of ease of polymerization control. Examples of solvents used in solution polymerization include: acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl acetate, ethyl acetate, butyl acetate, toluene, xylene, anisole, cyclohexanone, and isopropanol. The polymerization temperature can be set to, for example, around 60°C to 120°C, and the polymerization time can be set to around 2 hours to 12 hours.

[0104] The polymerization initiator used in the polymerization of (meth)acrylic resin is preferably a free radical polymerization initiator. Peroxides and azo compounds are suitable as free radical polymerization initiators.

[0105] [Initiator (C)]

[0106] As described above, the resin composition layer contains an initiator (C), which can be either a thermal polymerization initiator or a photopolymerization initiator. From the viewpoint that it is less likely to cause defects due to insufficient irradiation on substrates with complex shapes, a thermal polymerization initiator is preferred. Furthermore, as... Figure 4 As shown in process (VI), by applying pressure and heat simultaneously for hardening, warping or lifting caused by hardening shrinkage can be reduced to a minimum, and thermal polymerization initiators are efficient in this respect. Furthermore, photopolymerization initiators can also crack under heat, but they tend to yellow easily. On the other hand, thermal polymerization initiators are less prone to yellowing due to cracking residue, and are therefore more preferable.

[0107] In this embodiment, a thermal cationic polymerization initiator or a thermal free radical polymerization initiator can be used as the thermal polymerization initiator. Since the colorless resin composition layer exhibits good storage stability and rapid hardening after cracking, thus increasing production speed, a thermal free radical polymerization initiator is preferred.

[0108] Thermal cationic polymerization initiators have the function of generating ions through heat. Examples of cationic initiators include: sulfonium cations, quaternary ammonium cations, and monazine cations. Examples of anionic initiators include: antimony hexafluoride anion, phosphorus hexafluoride anion, tetra(pentafluorophenyl)borate anion, and trifluoromethanesulfonic acid.

[0109] Thermal free radical polymerization initiators have the function of generating free radicals through heat. Examples of thermal free radical polymerization initiators include organic peroxide polymerization initiators and azo thermal polymerization initiators. From the viewpoint of preventing yellowing, organic peroxide polymerization initiators are preferred.

[0110] Examples of organic peroxide polymerization initiators include: diacetyl peroxide, di-tert-butyl peroxide, di-tert-hexyl peroxide, diisopropylbenzene peroxide, tert-butylisopropylbenzene peroxide, α,α'-bis(tert-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexyn-3,2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, 1,3-bis(tert-butylperoxyisopropyl)hexane, (2-ethylhexanoyl)(tert-butyl)peroxide, and other dialkyl peroxides.

[0111] Dipropionyl peroxide, tert-butyl peroxyacetic acid ester, tert-butyl peroxybenzoate, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, bis(3,5,5-trimethylhexanoyl)peroxide, 1,1,3,3-tetramethylbutyl peroxyneodecanate, α-isopropylphenyl peroxyneodecanate, tert-butyl peroxyneodecanate, tert-hexyl peroxyneodecanate, tert-butyl peroxyneoheptanoate, tert-hexyl peroxypentanoate, tert-butyl peroxypentanoate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, tert-pentyl peroxy-2-ethylhexanoate, tert-butyl peroxy-2-ethylhexanoate Peroxide esters include tert-butyl peroxide isobutyrate, di-tert-butyl peroxide hexahydroterephthalate, 1,1,3,3-tetramethylbutyl peroxide-3,5,5-trimethylhexanoate, tert-amyl peroxide-3,5,5-trimethylhexanoate, tert-butyl peroxide-3,5,5-trimethylhexanoate, dibutyl peroxide trimethyl adipate, 2,5-dimethyl-2,5-di-ethylhexanoyl peroxide hexane, tert-hexyl peroxide-2-ethylhexanoate, tert-hexyl peroxide isopropyl monocarbonate, tert-butyl peroxide lauryl ester, tert-butyl peroxide isopropyl monocarbonate, and tert-butyl peroxide-2-ethylhexyl monocarbonate.

[0112] Ketone peroxides such as methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, tert-butyl benzoate, neopentyl tert-butyl peroxide;

[0113] 2,2-bis(tert-butylperoxy)butane, 2,2-bis(4,4-di-tert-butylperoxycyclohexyl)propane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-butylperoxy)cyclohexane-1,1-bis(tert-hexylperoxy)cyclohexane, 4,4-bis(tert-butylperoxy)valerate butyl valerate and other peroxide ketals;

[0114] Hydroperoxides such as tert-butyl hydroperoxide, cumene hydroperoxide, diisopropylbenzene hydroperoxide, 2,5-dimethylcyclohexane-2,5-dihydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, and p-methane hydroperoxide.

[0115] Diacyl peroxide, didecyl peroxide, dilauryl peroxide, diisobutyryl peroxide, bis-3,5,5-trimethylhexanol peroxide, m-toluylbenzoyl peroxide, succinic acid peroxide, 2,4-dichlorobenzoyl peroxide, and other diacyl peroxides.

[0116] Dicarbon peroxides such as bis(tert-butylcyclohexyl)peroxide, diisopropyl peroxide, di-n-propyl peroxide, di(2-ethoxyethyl)peroxide, tert-butyl peroxide isopropyl carbonate, di-2-ethylhexyl peroxide, di-sec-butyl peroxide, di-3-methoxybutyl peroxide, di-2-ethylhexyl peroxide, tert-amyl peroxide isopropyl carbonate, tert-butyl peroxide-2-ethylhexyl carbonate, and 6-bis(tert-butylperoxycarboxyoxy)hexane are available, but are not limited to these. From the viewpoint of preserving stability, dialkyl peroxides are preferred, and di-tert-butyl peroxide is more preferred.

[0117] From the viewpoint of preserving stability, 2,2'-azobispropionamide is preferred as an initiator for azo thermal polymerization, and more preferably 2,2'-azobis(N-butyl-2-methylpropionamide).

[0118] The preferred 10-hour half-life temperature for the thermal free radical polymerization initiator is 60°C to 180°C, more preferably 70°C to 140°C, and even more preferably 80°C to 120°C. Setting the temperature above 60°C improves the storage stability of the colorless resin composition layer, while setting it below 180°C reduces the storage stability of the colorless resin composition layer. Figure 4 In processes such as (IV), warping caused by the different shrinkage rates of the substrate or sealing layer precursor α is reduced.

[0119] The 10-hour half-life temperature is the temperature at which the thermal polymerization initiator, through thermal decomposition, reduces to half its initial mass after 10 hours. Specifically, a thermal polymerization initiator solution is prepared using an inert solvent and sealed in a nitrogen-purged glass tube containing the free radicals of the initiator. This solution is then immersed in a thermostat set at a predetermined temperature for 10 hours to allow for thermal decomposition, and the amount of remaining initiator is measured. This series of operations is performed at several temperature points, and the half-life can be determined from the resulting linear curve.

[0120] The content of the thermal free radical polymerization initiator relative to 100 parts by weight of resin (A) is preferably 0.01 to 20 parts by weight, more preferably 0.05 to 10 parts by weight, and even more preferably 0.1 to 5 parts by weight. By setting the content to the above, the adhesion can be suitably adjusted.

[0121] Examples of photopolymerization initiators include: triazine-based photopolymerization initiators, borate ester-based photopolymerization initiators, carbazole-based photopolymerization initiators, acetophenone-based photopolymerization initiators, and oxime ester-based photopolymerization initiators. Acetophenone-based and oxime ester-based photopolymerization initiators exhibit less yellowing during the heat aging process and are therefore preferred.

[0122] From the viewpoint of preventing yellowing, the content of photopolymerization initiator is preferably 0.5 to 10 parts by mass relative to 100 parts by mass of resin (A), and more preferably 0.5 to 5 parts by mass.

[0123] [Other ingredients]

[0124] The colorless resin composition layer may also contain other components without prejudice to the purpose of this disclosure. For example, refractive index modifiers, crosslinking agents, monomers, surface conditioning additives, curing accelerators, curing delay agents, softeners, antistatic agents, lubricants, anti-blocking agents, adhesion improvers, etc., may be added. As refractive index modifiers, examples include urethane (meth)acrylates or inorganic fillers.

[0125] Compared to (meth)acrylic resins, urethane (meth)acrylates have a higher refractive index and are more compatible, making it easier to adjust the refractive index of the colorless resin composition layer for embedding while maintaining transparency.

[0126] Carbamate (meth)acrylates are products of the reaction between compounds having isocyanate groups and (meth)acrylates having hydroxyl groups, with (meth)acryloyl groups at the end of the molecule.

[0127] As a compound having an isocyanate group, it is preferable to use a polyfunctional compound having an isocyanate group to react a (meth)acrylate having one hydroxyl group, or to use a monofunctional compound having an isocyanate group to react a (meth)acrylate having multiple hydroxyl groups to obtain a carbamate (meth)acrylate having multiple (meth)acryloyl groups.

[0128] Large-sized urethane (meth)acrylates can be obtained by reacting isocyanate-based prepolymers, which are produced by reacting various diols or diamines with compounds with low molecular weight and isocyanate groups, with hydroxyl-containing (meth)acrylates.

[0129] Examples of diols include those with a straight-chain aliphatic structure or those with a branched-chain aliphatic structure. Examples of diamines include those with alicyclic structures, as well as those with a similar straight-chain aliphatic structure or those with a branched-chain aliphatic structure.

[0130] Carbamate (meth)acrylates with multiple (meth)acryloyl groups are rapidly cured by peroxides or ultraviolet light through unsaturated carbon bonds derived from (meth)acrylates. The resulting cured products exhibit high crosslinking density, excellent chemical resistance, and transparency.

[0131] The urethane (meth)acrylate is preferably a molecule having three or more double-bonded functional groups.

[0132] The weight average molecular weight (Mw) of the urethane (meth)acrylate is preferably 300 to 4000. With a Mw of 4000 or less, a colorless resin composition layer with excellent transparency and good compatibility with (meth)acrylate resins can be obtained. With a Mw of 300 or more, exudation from the colorless resin composition layer is prevented.

[0133] When the total amount of urethane (meth)acrylate added relative to (meth)acrylate resin is set to 100% by mass, it is preferably (meth)acrylate resin / urethane (meth)acrylate = 95% / 5% to 60% / 40%, more preferably 90% / 10% to 80% / 20%. By having urethane (meth)acrylate account for 5% or more by mass, it is easier to adjust in the direction of increasing the refractive index of the cured product, and by having 40% or less by mass, the exudation of urethane (meth)acrylate is suppressed.

[0134] Examples of inorganic fillers with a refractive index of 1.55 or higher include: borosilicate glass, alumina, magnesium hydroxide, barium sulfate, calcium carbonate, titanium dioxide, zinc oxide, antimony trioxide, magnesium oxide, zirconium oxide, talc, kaolinite, mica, alkali magnesium carbonate, sericite, montmorillonite, kaolin, bentonite, boron nitride, aluminum nitride, and titanium nitride. Among these, titanium dioxide, alumina, and zirconium oxide are preferred from the perspective of easily adjusting the refractive index while maintaining transparency.

[0135] Furthermore, when the refractive index of resin (A) is high, components with low refractive index can be added to adjust the refractive index of the colorless resin composition layer for embedding.

[0136] During hot pressing or heat aging in the pressing process, the crosslinking agent undergoes a crosslinking reaction with the reactive functional groups of the resin (A), thereby improving the cohesiveness and adhesion of the resin composition layer. The crosslinking agent has multiple functional groups capable of reacting with the functional groups of the resin (A). Examples of crosslinking agents include known compounds such as silane coupling agents, compounds containing anhydride groups, imidazole compounds, isocyanate compounds, aziridine compounds, and amine compounds. Isocyanate compounds, aziridine compounds, and imidazole compounds are preferred for improving adhesion to circuits or substrates. Silane coupling agents that improve adhesion to glass, such as glass substrates, are particularly preferred.

[0137] Examples of aziridine compounds include: trimethylolpropane tris[3-(aziridine-1-yl)propionate], tetramethylolmethane-tri-β-aziridine propionate, N,N'-diphenylmethane-4,4'-bis(1-aziridine carboxylamide), N,N'-hexamethylene-1,6-bis(1-aziridine carboxylamide), tris-2,4,6-(1-aziridine)-1,3,5-triazine, and 4,4'-bis(ethyleneiminocarbonylamino)diphenylmethane.

[0138] Isocyanate compounds are isocyanates having two or more isocyanate groups. Isocyanate compounds are preferably, for example, isocyanate monomers such as aromatic polyisocyanates, aliphatic polyisocyanates, aromatic aliphatic polyisocyanates, and alicyclic polyisocyanates, as well as their biuret forms, urate forms, and adducts.

[0139] From the viewpoint of forming a fully cross-linked structure, isocyanate compounds are preferably trifunctional isocyanate compounds.

[0140] Silane coupling agents are compounds in which hydrolyzable groups such as methoxy and ethoxy groups are bonded to Si atoms via alkylene groups.

[0141] Examples of silane coupling agents include: 3-(meth)acryloyloxypropyltrimethoxysilane, 3-(meth)acryloyloxypropyltriethoxysilane, 3-(meth)acryloyloxypropyltripropoxysilane, 3-(meth)acryloyloxypropyltributoxysilane, 3-(meth)acryloyloxypropylmethyldimethoxysilane, 3-(meth)acryloyloxypropylmethyldiethoxysilane, and other alkoxysilane compounds containing (meth)acryloyloxy groups;

[0142] Vinyltrimethoxysilane, vinyltriethoxysilane, vinyltriisopropoxysilane, vinyltributoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane, and other alkoxysilane compounds containing vinyl groups;

[0143] 3-Aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltripropoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropylmethyldiethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldiethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane and other alkoxysilane compounds containing an amino group;

[0144] Alkoxysilane compounds containing a thiol group, such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropyltripropoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 3-mercaptopropylmethyldiethoxysilane.

[0145] Alkoxysilane compounds having one epoxy group, such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyltripropoxysilane, 3-glycidoxypropyltributoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane.

[0146] Tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetrabutoxysilane, and other tetraalkoxysilane compounds;

[0147] 3-Chloropropyltrimethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, n-decyltrimethoxysilane, n-decyltriethoxysilane, styryltrimethoxysilane, phenyltrimethoxysilane, diphenyldimethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylene)propylamine, 1,3,5-tris(3-trimethoxysilylpropyl)isocyanurate, 3-isocyanate-propyltrimethoxysilane, 3-isocyanate-propyltriethoxysilane, hexamethyldisilazane, and silicone resins containing alkoxysilyl groups within the molecule, etc.

[0148] When the functional groups are the same as those of resin (A), the cohesiveness and adhesion are improved by adopting a cross-linking structure. Therefore, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, vinyltrimethoxysilane, and vinyltriethoxysilane are preferred.

[0149] The content of crosslinking agent is preferably 0.01 to 10 parts by weight relative to 100 parts by weight of resin (A). By setting this content, the cohesive strength is improved, and the adhesion to various sealing objects is enhanced.

[0150] · <Water vapor barrier layer 4>

[0151] Next, the water vapor barrier layer 4, which together with the colorless resin composition layer 3 for embedding, constitutes the sealing layer precursor α, will be described.

[0152] The water vapor barrier layer is configured to suppress ion deposition or circuit corrosion caused by water vapor. Importantly, it has low water vapor permeability and, importantly, low moisture absorption.

[0153] That is, importantly, the water vapor permeability is less than 100 g / (m 2·24 hours)], preferably 70 [g / (m 2 ·24 hours) or less, more preferably 50 [g / (m 2 ·24 hours) or less, and more preferably 30 [g / (m 2 ·24 hours) or less, particularly preferably 10 [g / (m 2 (24 hours) or less.

[0154] Furthermore, the moisture absorption rate of the water vapor barrier layer 4 is preferably 1.5% by mass or less, more preferably 1% by mass or less, and even more preferably 0.8% by mass or less.

[0155] Importantly, the refractive index of the water vapor barrier layer 4 is 1.53 ± 0.03, and preferably the difference between it and the refractive index of the substrate on which the light-emitting element is mounted is as small as possible. The substrate will be described later.

[0156] Furthermore, regarding the display performance of the display, it is important that the water vapor blocking layer and the colorless resin composition layer 3 for embedding are both colorless, or more precisely, colorless and transparent. Specifically, regarding colorlessness, it is important that the b value in the Lab value is 1.5 or less, preferably 1.0 or less. Furthermore, regarding transparency, it is important that the haze is 3.0% or less, preferably 1.0% or less.

[0157] Furthermore, as Figure 4 (I-1) Figure 9 As shown in (VII), a molding process is performed when manufacturing a sealing member to seal a light-emitting element mounted on a substrate. Therefore, it is also required that the water vapor barrier layer 4 suppresses pressure unevenness during insertion, and that the colorless resin composition layer does not overflow from the target area during insertion. In addition, when manufacturing a member sealing a light-emitting element, a cleaning process using organic solvents or the like is sometimes performed. Therefore, from the viewpoint of protecting the colorless resin composition layer or its hardened form from damage during these processes, the water vapor barrier layer is also required to have low shrinkage and chemical resistance.

[0158] To satisfy certain requirements for rigidity, flexibility, and chemical resistance, the water vapor barrier layer 4 is preferably a thermoplastic resin film. Examples of thermoplastic resin films include polyester films, polyolefin films, polyvinyl chloride films, polyurethane films, nylon films, acrylic films, triacetyl cellulose films, etc., and films having a metal oxide film such as alumina can also be included.

[0159] Examples of polyester films include polyethylene terephthalate (PET) films, polybutylene terephthalate (PET) films, and polyethylene naphthalate (PET) films. Examples of polyolefin films include polypropylene (PP) films, polyethylene (PE) films, and cycloolefin-based films. Among cycloolefin-based films, in addition to cycloolefin (cycloolefin polymer (COP)) films, films formed by molding cycloolefin copolymers (COC) or cycloolefin block copolymers (CBC) can also be included.

[0160] In terms of high transparency and low thermal shrinkage, transparent polyimide, polyethylene terephthalate, and polyethylene naphthalate are preferred. From the viewpoint of water vapor barrier properties, polyethylene terephthalate film with metal oxide film is preferred. In particular, cycloolefin film with a small difference in refractive index from alkali-free glass, which is important for the substrate on which the light-emitting element is placed, is preferred.

[0161] The thickness of the water vapor barrier layer is preferably 5 μm to 50 μm, more preferably 8 μm to 40 μm, and even more preferably 10 μm to 20 μm. A thickness of 5 μm or more improves water vapor barrier performance and ensures stable embedding. A thickness of 50 μm or less improves transparency. Since the display is preferably thinner, the thickness of the water vapor barrier layer being within a more preferred range allows for a high level of achievement of the desired objective. Furthermore, within a more preferred range, when embedding the colorless resin composition layer into the gap of the light-emitting element, unevenness is less likely to occur on the surface of the water vapor barrier layer, further improving the water vapor barrier performance after sealing.

[0162] · <First Membrane 2>, <Second Membrane 5>

[0163] like Figure 1 (1) Figure 1 As shown in (2), the sealing layer precursor α is sandwiched between the first membrane 2 and the second membrane 5. The first membrane 2 and the second membrane 5 are used to form the sealing layer sheet as shown in (2). Figure 4 (I-1) Figure 8 As shown in (VII), the multiple light-emitting elements 7 placed on the substrate are peeled off during the sealing process.

[0164] ·[First Membrane 2]

[0165] The first membrane 2 is not particularly limited, and examples include: polyester membrane, polyolefin membrane, polyvinyl chloride membrane, polyurethane membrane, nylon membrane, acrylic membrane, triacetyl cellulose membrane, etc.

[0166] Examples of polyester films include polyethylene terephthalate (PET) films, polybutylene terephthalate (PET) films, and polyethylene naphthalate (PET) films. Examples of polyolefin films include polypropylene (PP) films, polyethylene (PE) films, and cycloolefin (COO) films. From a processing point of view, polyester films or polyolefin films are preferred.

[0167] The first membrane 2 has a release layer on the surface facing the colorless resin composition layer 3 for embedding. The release layer is preferably formed by coating the membrane with a release agent such as silicone resin, alkyd resin, fluororesin, or melamine resin; from the viewpoint of treatment (preventing unintended separation), a release layer using silicone resin is more preferred. The peel force of the first membrane 2 is preferably 0.1 gf / 20 mm to 3 gf / 20 mm, more preferably 0.3 gf / 20 mm to 2 gf / 20 mm, and even more preferably 0.5 gf / 20 mm to 1 gf / 20 mm.

[0168] The peel force of the first film 2 can be adjusted through the demolding treatment of the release layer. For example, it can be adjusted by the type of release agent, the amount of release agent applied, and the surface roughness of the release layer. To reduce the peel force, it is effective to increase the surface roughness and the amount of release agent applied; to increase the peel force, the opposite adjustment is sufficient.

[0169] The peel force of the first film 2 can be measured, for example, by attaching the second film 5 of the sealing layer forming sheet to a stainless steel (steel use stainless, SUS) plate, and peeling the first film 2 from the colorless resin composition layer 3 for embedding at a peel angle of 180° and a peel speed of 300 mm / min in an environment of 23°C and 50% relative humidity.

[0170] In addition to the release layer, the first membrane 2 may also have a functional layer. Examples of functional layers include an antistatic layer and an anti-adhesion layer.

[0171] The thickness of the first film 2 is preferably 2 μm to 250 μm, more preferably 10 μm to 100 μm, and even more preferably 20 μm to 60 μm. When the first film 2 is provided with a release layer or a functional layer, the thickness includes both the release layer and the functional layer. By setting it to the aforementioned range, the fluctuations of the first film 2 can be controlled to transfer to the colorless resin composition layer, thereby forming a uniform colorless resin composition layer.

[0172] like Figure 1As shown in (1), the first film 2 is preferably directly laminated with the colorless resin composition layer 3 for embedding. When the first film 2 is directly laminated with the colorless resin composition layer 3 for embedding, the surface roughness Ra of the surface of the first film 2 in contact with the colorless resin composition layer 3 for embedding is preferably 0.02 μm or more. The surface roughness of the surface of the first film 2 in contact with the colorless resin composition layer 3 for embedding is transferred to the surface of the colorless resin composition layer 3 for embedding. Therefore, by using the first film 2 with such a surface roughness, in Figure 4 During the process shown in (IV), the colorless resin composition layer 3 for embedding is less likely to be excessively adsorbed onto the surface of the light-emitting element, making it easier to correct the placement position of the sealing layer forming sheet 1. Furthermore, by using the colorless resin composition layer 3 for embedding with a surface roughness Ra of 0.02 μm or higher, Figure 4 of (V), Figure 5 During the process shown in (V-2), air is less likely to remain at the interface between the substrate, the light-emitting element, and the colored resin composition layer and the colorless resin composition layer, resulting in a good appearance. Specifically, in terms of suppressing / preventing adhesion and suppressing / preventing air entrainment, the surface roughness Ra of the first film 2 and the embedding colorless resin composition layer 3 in contact with the first film 2 is preferably 0.02 μm or more, more preferably 0.1 μm or more, and even more preferably 0.5 μm or more. In terms of minimizing the impact of unevenness on the water vapor barrier layer 4, the upper limit of the surface roughness is preferably 20% or less of the thickness of the embedding colorless resin composition layer 3.

[0173] Furthermore, the cut-off level difference Rδc of the profile curve of the surface of the first film 2 in contact with the colorless resin composition layer 3 for embedding is preferably 0.05 μm or more, more preferably 0.1 μm or more, and even more preferably 0.5 μm or more. Additionally, the cut-off level difference Rδc of the profile curve is preferably 20 μm or less, more preferably 10 μm or less, and even more preferably 6 μm or less. By transferring the embossing of the first film 2 to the colorless resin composition layer 3 for embedding, the colorless resin composition layer 3 for embedding does not immediately form a tight seal with the LED element or substrate, allowing for correction of positional misalignment, thus facilitating the removal of voids during embedding in a vacuum environment. Within the preferred range, excellent correction of positional misalignment occurs while sliding on the surface of the object being sealed, and excellent removal of voids.

[0174] ·[Second membrane 5]

[0175] The second membrane 5 is in Figure 4 (V)~ Figure 4 (VI) Figure 5 (V-2) Figure 5During the pressing or hardening (heating or ultraviolet (UV) irradiation) processes shown in (VI), the layer functions as a buffer layer to support the water vapor barrier layer and suppress pressure deviations or mold marks. For more reliable support of the water vapor barrier layer, a micro-adhesive layer is preferably present on the surface in contact with the water vapor barrier layer.

[0176] The substrate of the second membrane 5 is not particularly limited, and examples include polyester membrane, polyolefin membrane, polyvinyl chloride membrane, polyurethane membrane, nylon membrane, acrylic membrane, triacetyl cellulose membrane, etc.

[0177] Examples of polyester films include polyethylene terephthalate (PET) films, polybutylene terephthalate (PET) films, and polyethylene naphthalate (PET) films. Examples of polyolefin films include polypropylene (PP) films, polyethylene (PE) films, and cycloolefin (CO) films. From a processing point of view, polyimide films, polyester films, or polyolefin films are preferred, and further considering heat resistance, polyimide films, polyethylene naphthalate (PET) films, and polyethylene terephthalate (PET) films are more preferred.

[0178] The micro-adhesive layer disposed on the surface of the second membrane 5 can be formed using various adhesives. Examples of adhesives include acrylic, urethane, silicone, elastic, and ester-based adhesives. From the viewpoint of heat resistance, acrylic, urethane, and silicone adhesives are preferred; furthermore, from the viewpoint of low impurity content, acrylic or urethane adhesives are preferred. The thickness of the micro-adhesive layer of the second membrane 5 is preferably 1 μm to 50 μm, more preferably 2 μm to 20 μm, and particularly preferably 3 μm to 10 μm. A thickness of 1 μm or more provides good adhesion, while a thickness of 50 μm or less prevents the micro-adhesive layer from overflowing from the end of the second membrane 5 during embedding.

[0179] The adhesion force to the water vapor barrier layer is preferably 1gf / 25mm to 300gf / 25mm, more preferably 2gf / 25mm to 200gf / 25mm, and even more preferably 3gf / 25mm to 100gf / 25mm.

[0180] The adhesion of the second film 5 to the water vapor barrier layer 4 can be adjusted according to the type of adhesive, the coating amount, and the surface roughness. For example, increasing the surface roughness to reduce adhesion and increasing the coating amount to increase adhesion are effective treatments. The adhesion to the water vapor barrier layer 4 can be measured by fixing the surface of the colorless resin composition layer 3 for embedding the sealing sheet onto an SUS plate, and peeling the second film 5 at a peel angle of 180° and a peel speed of 300 mm / min in an environment of 23°C and 50% relative humidity.

[0181] The thickness of the second film 5 is preferably 12 μm to 188 μm, more preferably 12 μm to 100 μm, and even more preferably 20 μm to 60 μm. By setting it to the range described above, the pressure transmission applied to the colorless resin composition layer during the pressing process is controlled, the colorless resin composition layer flows uniformly, thereby achieving good embedding properties.

[0182] The tensile storage modulus E'(100) of each of the colorless resin composition layer 3, the water vapor barrier layer 4, and the second film 5 at 100°C preferably satisfies the following relationship.

[0183] E'4(100) / E'3(100) is between 100 and 1000, and

[0184] E'5(100) / E'4(100) is 0.5 to 3.

[0185] E'3(100) represents the tensile storage elastic modulus of the colorless resin composition layer 3 for embedding at 100°C, E'4(100) represents the tensile storage elastic modulus of the water vapor barrier layer 4 at 100°C, and E'5(100) represents the tensile storage elastic modulus of the second film 5 at 100°C.

[0186] E'4(100) / E'3(100) is preferably 100 to 1000, more preferably 200 to 800, and even more preferably 400 to 700. With this relationship between E'4(100) and E'3(100), the embedding performance of the object to be sealed is excellent, and the unevenness of the object originating from the light-emitting element does not affect the surface of the water vapor barrier layer. With a value of 100 or higher, the water vapor barrier layer 4, being sufficiently rigid compared to the colorless resin composition layer 3 for embedding, can uniformly and sufficiently press the colorless resin composition layer 3 into the recess of the object to be sealed. With a value of 1000 or lower, the water vapor barrier layer 4 is not too rigid, preventing pressure deviations caused by the unevenness of the object to affect the water vapor barrier layer 4, and thus forming an uneven pattern on the surface of the water vapor barrier layer 4. Furthermore, E'5(100) / E'4(100) is preferably 0.5 to 3, and even more preferably 1.1 to 2.0. By maintaining this relationship between E'5 (100) and E'4 (100), it prevents the formation of an uneven pattern on the surface of the water vapor barrier layer 4 that corresponds to the unevenness of the object being sealed. In a more preferred range, since the second film 5 is equal to or slightly harder than the water vapor barrier layer 4, the second film 5 can further assist in the embedding of the resin composition layer 3 for embedding. Each tensile storage modulus is obtained by measuring the dynamic viscoelasticity using a dynamic viscoelasticity measuring device DVA-200 / L2 (manufactured by IT Measurement Control Co., Ltd.), at a frequency of 10 Hz, a measurement temperature range of -50°C to 150°C, a heating rate of 5°C / min, and in tensile mode, and reading the storage modulus at 100°C.

[0187] The sealing layer forming sheet 1 can be obtained, for example, as follows: A coating liquid for forming an embedding colorless resin composition layer is applied to one side of the first film 2 and dried to form an embedding colorless resin composition layer 3. Additionally, a water vapor barrier layer 4 is laminated on one side of the second film 5. Then, the embedding colorless resin composition layer 3 and the water vapor barrier layer 4 are laminated together.

[0188] Alternatively, a coating solution for forming an embedding colorless resin composition layer is applied to one side of the first film 2 and dried to form an embedding colorless resin composition layer 3. Then, a water vapor barrier layer 4 is laminated onto the embedding colorless resin composition layer 3. Next, a second film 5 is laminated onto the water vapor barrier layer 4.

[0189] Alternatively, a water vapor barrier layer 4 is laminated on one of the surfaces of the second membrane 5. Then, a coating liquid for forming an embedding colorless resin composition layer is applied to the water vapor barrier layer 4 and allowed to dry, forming an embedding colorless resin composition layer 3. Finally, the first membrane 2 is laminated on the embedding colorless resin composition layer 3.

[0190] The coating method for forming the colorless resin composition layer for embedding can be any known method, such as roller coating, corner roller coating, die lip coating, die coating, reverse coating, screen printing, gravure coating, etc. After coating, it can be dried using a hot air oven, infrared heater, etc.

[0191] After manufacturing the sealing layer forming sheet 1, or simultaneously manufacturing the sealing layer forming sheet 1, it is wound into a roll on a core to obtain a rolled sealing layer forming sheet. The winding length can be designed according to the application. From the viewpoint of improving productivity, it is preferably 30m or more, and more preferably 100m or more. From the viewpoint of manufacturing yield, the winding length is preferably set to 10,000m or less. In terms of ease of winding when rolled into a roll, the thickness of the sealing layer forming sheet is preferably 60μm to 200μm.

[0192] As a method for forming a roll-shaped sealing layer sheet 1, the winding method can be used to form a roll-shaped sealing layer sheet 1. Figure 1 The sheet shown in (1) is wound with the first film 2 as the core side, or as shown in (1). Figure 1 As shown in (2), with the first film 2 overlapping on the surface of the second film 5 that is not in contact with the water vapor barrier layer 4, the embedded colorless resin composition layer 3 is wound as the core side.

[0193] In the latter case, after the second turn, the first film 2 is in contact with the colorless resin composition layer 3 for embedding. When using the roll-shaped sealing layer forming sheet 1, if the roll is unrolled, the first film 2 can be peeled off immediately, exposing the colorless resin composition layer 3 for embedding. Therefore, it is preferable in terms of improving the productivity of the component 8 that seals the light-emitting element 7.

[0194] Furthermore, the latter roll-shaped sealing layer forming sheet 1 can also be obtained by: stacking the first film 2 and the second film 5, stacking the water vapor barrier layer 4 on the other side of the second film 5, applying the coating liquid for forming the embedding colorless resin composition layer on the other side of the water vapor barrier layer 4 and drying it to form the embedding colorless resin composition layer, and then winding the embedding colorless resin composition layer 3 as the inside.

[0195] • [A component 8 sealed with multiple light-emitting elements]

[0196] Next, the component 8 (hereinafter also referred to as the sealing component or simply the component) which is sealed with multiple light-emitting elements will be described.

[0197] As described above, the sealing component 8 of this disclosure, which seals a plurality of light-emitting elements, includes a substrate 6, a plurality of light-emitting elements 7 spaced apart and mounted on the substrate 6, and a sealing layer. In the component 8 sealing the plurality of light-emitting elements, at least a portion of the depth direction of the gaps between the light-emitting elements 7 is composed of a material with a refractive index of 1.51 ± 0.03 and a water vapor transmission rate of 100 g / (m²). 2 The hardened layer 3' of the colorless resin composition layer 3 for embedding is embedded for 24 hours or more. The side that emits light from multiple light-emitting elements 7 (the side where the light-emitting elements 7 are formed) is sequentially embedded with the hardened layer 3' of the colorless resin composition layer 3 and the layer with a refractive index of 1.53 ± 0.03 and a water vapor transmittance of less than 100 g / (m 2 Water vapor barrier layer 4 covering (24 hours)

[0198] In addition, the sealing component 8 containing multiple light-emitting elements can be configured such that at least a portion of the depth direction of the gaps between the light-emitting elements 7 and / or at least a portion of the bottom surface of each gap is embedded in a hardened layer 9' of a colored resin composition, and the remaining portions of the gaps between the light-emitting elements 7 are embedded in a hardened layer 3' of a colorless resin composition layer 3.

[0199] Various configurations of the gaps between the light-emitting elements 7 in the sealed component 8 containing multiple light-emitting elements are shown. Figure 2 (1)~ Figure 2 (5) Figure 2(1) is a component in which the gap of the light-emitting element 7 does not have a hardened part 9' of the embedded colored resin composition 9, and represents a form in which the gap is embedded by the hardened part 3' of the embedded colorless resin composition layer 3, and the hardened part 3' of the embedded colorless resin composition layer 3 is covered by the water vapor barrier layer 4.

[0200] Figure 2 (2) Figure 2 (5) indicates that at least a portion of the gap in the light-emitting element 7 has a hardened layer 9' of the embedded colored resin composition 9, i.e., a reflective layer or a color mixing prevention layer, which enhances luminance. The luminance-enhancing layer is disposed on a side surface other than the display side (light emitting surface, the upper surface side in the figure) of the light-emitting element 7 or on the bottom surface of the gap, and there are no limitations on its placement method. Alternatively, it can be as follows: Figure 2 (2) The hardened material 9' of the colored resin composition 9 is embedded in such a way that it does not completely cover the side of the light-emitting element 7; or as Figure 2 (3) The hardened portion 9' of the embedded colored resin composition, used to fill the gaps of the light-emitting element, covers the side of the light-emitting element 7, and the surface of the hardened portion 9' of the embedded colored resin composition 9 in the gap has irregularities formed by an etching process, etc.; or as Figure 2 As in (4), the substrate, with a thin layer of hardened material 9' of colored resin composition 9 covering the sides of the light-emitting element 7 and the bottom of the gap, is embedded, while having a deep space in the depth direction in the middle of the gap; or as Figure 2 In step (5), the hardened portion 9' of the embedded colored resin composition 9 is disposed in the gap without being in contact with the light-emitting element 7. Depending on the presence or absence of the hardened portion 9' of the embedded colored resin composition 9 and its shape, the shape of the object to be embedded by the embedded colorless resin composition layer 3 can vary. However, the interface between the hardened portion 3' of the embedded colorless resin composition layer 3 and the water vapor barrier layer 4 stacked on the hardened portion 3' of the embedded colorless resin composition layer 3, and the surface of the water vapor barrier layer 4, are preferably as parallel as possible to the surface of the substrate 6 on which the light-emitting element 7 is placed, regardless of the shape of the gap to be sealed, and the surface of the water vapor barrier layer 4 is preferably as smooth as possible.

[0201] ·<Substrate 6>

[0202] The material of the substrate 6 on which the light-emitting element 7 is mounted is not particularly limited, and examples include: acrylic, urethane, polycarbonate, epoxy resin, polyimide, glass, glass epoxy resin, paper, cloth, aluminum, ceramic, or polyethylene terephthalate. It can also be extended to applications in transparent displays; from the viewpoints of cost, durability, and transparency, glass is preferred, especially the material containing electrode portions.

[0203] To prevent corrosion of the light-emitting element by ionic components, alkali-free glass is preferred as the glass.

[0204] Furthermore, the refractive index of the glass substrate is preferably 1.49 to 1.59, more preferably 1.50 to 1.55. The refractive index can be adjusted, for example, by adjusting the ratio of silicon oxide, aluminum oxide, and boron oxide; generally, increasing the ratio of boron oxide increases the refractive index. Besides adding boron oxide, the refractive index can also be increased by adding alkaline earth oxides.

[0205] ·<Light-emitting element 7>

[0206] As the light-emitting element 7 mounted on the substrate 6, LED elements can be listed, and micro LED elements are suitable.

[0207] The preferred size of the microLED element is a thickness of less than 100 μm and an area of ​​40,000 μm when viewed from above. 2 The following size is more preferably a thickness of 50 μm or less and an area of ​​10,000 μm when viewed from above. 2 The following dimensions are preferred: a thickness of 20 μm or less and an area of ​​2,500 μm when viewed from above. 2 The following sizes are used to form a display that uses multiple optical semiconductor elements as a light source by mounting multiple LED elements on a substrate on which wiring or circuitry is formed.

[0208] The spacing between the microLED elements mounted on the substrate is, for example, 10 μm to 5,000 μm. When red, green, and blue microLED elements are grouped together and mounted as a pixel on the substrate, the spacing between the pixels is, for example, 10 μm to 2,000 μm, preferably 20 μm to 1,800 μm, more preferably 500 μm to 1,500 μm. The spacing between the microLED elements in a pixel is, for example, 10 μm to 200 μm, preferably 10 μm to 100 μm, more preferably 20 μm to 60 μm.

[0209] There is no particular limitation on the number of microLED elements. In display applications, the number of microLED elements used is determined by the display size or pixel count. Furthermore, there is no particular limitation on the emitted color of microLED elements; examples include red, green, blue, white, and yellow. MicroLEDs are formed from LED elements such as GaAs, GaP, AlGaInP, and InGaN, a sealing resin for sealing them, a packaging substrate, electrodes, etc., and operate at temperatures ranging from 25°C to 60°C.

[0210] • <Curing of layer 3 of colorless resin composition for embedding>

[0211] The hardened portion 3' of the colorless resin composition layer 3 is required to seamlessly embed the LED element and the substrate, the LED element and the substrate, and the luminance enhancement layer, and is required to have high transparency and water vapor barrier properties. The refractive index of the hardened portion of the colorless resin composition layer is substantially the same as that of the colorless resin composition layer, i.e., 1.51 ± 0.03. Furthermore, the difference between the refractive index of the hardened portion of the resin composition layer and the refractive index of the substrate on which the light-emitting element is mounted is preferably as small as possible.

[0212] If used Figure 3 To explain (1), the thickness T1 of the hardened layer 3' of the colorless resin composition layer 3 for embedding between the top surface of the light-emitting element 7 and the lower surface of the water vapor blocking layer 4 is preferably 5 μm to 30 μm, more preferably 7 μm to 25 μm, and particularly preferably 10 μm to 20 μm. When T1 is 30 μm or less, transparency is improved. When T1 is 5 μm or more, the uneven shape generated by the top surface of the light-emitting element 7 and the bottom surface of the gap between the light-emitting elements 7 is less likely to affect the surface of the water vapor blocking layer 4, thus improving water vapor blocking performance. By being within a more preferred range, the aforementioned objective can be achieved to a high degree.

[0213] In such Figure 3 When the hardened portion 9' of the embedded colored resin composition 9, as shown in (2), fills a portion of the gaps between the light-emitting elements 7, the thickness T1 of the hardened portion 3' of the embedded colorless resin composition layer 3 between the top surface of the light-emitting element 7 and the lower surface of the water vapor barrier layer 4 is preferably within the range described above. Furthermore, Figure 2 (3)~ Figure 2 The same applies to case (5).

[0214] · <Water vapor barrier layer 4>

[0215] like Figure 3 (1) Figure 3 As shown in (2), the thickness T2 of the water vapor barrier layer 4 in the component 8 which is sealed with multiple light-emitting elements is as described above.

[0216] Furthermore, the combined thickness of the hardened portion 3' of the colorless resin composition layer 3 and the water vapor barrier layer 4 is preferably 5 μm to 50 μm, more preferably 7 μm to 30 μm, and even more preferably 10 μm to 15 μm. By falling within the more preferred range, water vapor barrier properties and transparency are maintained at a high level while sealing the LED elements and substrate in the component, and the required thinness of the display is met.

[0217] • <Curing of colored resin composition 9 for embedding 9>

[0218] As for the colored resin composition 9 for embedding, similarly to the colorless resin composition layer 3 for embedding, a composition can be formed into a sheet by applying a coating liquid containing at least resin (A) and initiator (C), further containing a black or white pigment, and then drying it. Representative black pigments include carbon black, and representative white pigments include titanium oxide and zinc oxide.

[0219] based on Figure 10 (1-a)~ Figure 10 (3-d) describes various methods for forming a hardened material 9' of an embedded colored resin composition 9 between light-emitting elements 7.

[0220] For example, such as Figure 10 (1-a) Figure 10 As shown in (1-b), a sheet of colored resin composition 9 for embedding, which has a sufficient thickness compared to the height of the light-emitting element 7, is embedded and sealed to an object β1 by pressing or other methods (see reference). Figure 4 After the light-emitting element 7 in (I-1) is placed in the gap, as Figure 10 As shown in (1-c), it hardens.

[0221] Subsequently, the hardened portion 9' of the embedded colored resin composition 9 is removed by laser etching, chemical etching, or grinding until it reaches the same height as the light-emitting element 7, thereby obtaining... Figure 10 The sealed object β3 shown in (1-d) (refer to) Figure 9 (I-1) Figure 9 (VII)).

[0222] Furthermore, by thinning or excavating the hardened portion 9' of the colored resin composition 9 within the gaps of the light-emitting element 7, a result such as... can be obtained. Figure 10 (1-e) or Figure 10 The sealed object β2 shown in (1-f) (refer to) Figure 5 (I-1) Figure 6 (VII)).

[0223] Laser etching offers superior processing precision, while chemical etching boasts excellent productivity. For micro-LED components requiring fine fabrication, laser etching is the preferred option.

[0224] Or, such as Figure 10 As shown in (2-a), by placing a sheet of embedded colored resin composition 9, which is relatively thin compared to the height of the light-emitting element 7, on the upper surface of the light-emitting element 7, and using vacuum forming methods such as three-dimensional overlay method (TOM) molding, it is possible to achieve the following: Figure 10As in (2-b), the embedded colored resin composition 9 is disposed along the surfaces of the light-emitting element 7 and the substrate 6. Figure 10 The hardened form 9' of the embedded colored resin composition 9 can be obtained as in (2-c), and can be prepared by laser etching, chemical etching, or grinding, etc. Figure 10 (2-d) or Figure 10 The sealed object β2 shown in (2-d') (refer to) Figure 7 (I-1) Figure 7 (VII)).

[0225] In addition, such as Figure 8 (I-1) Figure 8 The hardened part 9' of the embedded colored resin composition 9, as shown in (VII), is located in the gap of the light-emitting element 7 but hardly contacts the side of the light-emitting element 7. The sealing object β2 can be obtained, for example, by laser stripping.

[0226] That is, such as Figure 10 As shown in (3-a), a colored resin composition 9 for embedding of the desired size is placed or formed on the release film 11 at a position corresponding to the gap of the light-emitting element 7. Next, as shown in (3-a), Figure 10 After the colored resin composition 9 for embedding is brought into contact with the substrate 6 in the gap of the light-emitting element 7 as shown in (3-b), a laser is irradiated from behind the release film (above in the figure), as shown. Figure 10 The colored resin composition 9 for embedding is detached from the release film as shown in (3-c). Then, a hardened form 9' of the colored resin composition 9 for embedding is obtained, thereby preparing a product as shown in (3-c). Figure 10 The sealed object β2 is shown in (3-d).

[0227] The component 8, which is sealed with multiple light-emitting elements 7, can be formed by various methods.

[0228] For example, preparing as Figure 4 As shown in (I-1), a sealed object β1 is provided on a substrate 6 with a plurality of light-emitting elements 7 (e.g., micro LED elements) spaced apart at a predetermined interval.

[0229] In addition, preparations such as Figure 4 The sealing layer forming sheet 1 is as shown in (II). Figure 4 As shown in (III), the first film 2 is peeled off from the sealing layer forming sheet 1, exposing the colorless resin composition layer 3 for embedding. The peeling method for peeling off the first film 2 from the sealing layer forming sheet 1 is not particularly limited. For example, the sealing layer forming sheet 1 in roll shape can be prepared and the sealing layer forming sheet 1 can be pulled out by roll-to-roll, while only the first film 2 is rolled up and peeled off.

[0230] Then, as Figure 4As shown in (IV), the exposed colorless resin composition layer 3 for embedding is placed such that it directly covers the upper surface of the light-emitting element 7 in the sealed object β1. In step (IV), in order to prevent gaps from forming at the contact surface between the upper surface of the light-emitting element 7 and the colorless resin composition layer 3 for embedding, and also to prevent gaps from forming between the light-emitting elements 7 in the next step, it is preferable to set the process to a vacuum or reduced pressure state. In addition, in order to improve the fluidity of the colorless resin composition layer in the next step, it is preferable to preheat it in step (IV). The heating temperature is preferably at least 10°C higher than the Tg of the resin composition, more preferably at least 30°C higher. That is, the heating temperature is based on the Tg of the resin composition described later, preferably 30°C to 200°C, more preferably 40°C to 150°C, more preferably 50°C to 130°C, and particularly preferably 60°C to 110°C.

[0231] Then, as Figure 4 As shown in (V), the colorless resin composition layer 3 for embedding is flowed by pressing and filled into the spaces between the light-emitting elements 7. It can also be filled around the light-emitting elements 7. During pressing, in order to improve the flowability of the colorless resin composition layer 3 for embedding, heating is preferable. However, if the temperature is too high, the colorless resin composition layer 3 for embedding will harden, which will hinder the filling. Therefore, a temperature lower than the next step (VI), i.e., a temperature similar to that of step (IV), is preferred. From the viewpoint of the filling properties of the colorless resin composition layer 3 for embedding, the heating temperature is preferably 30°C to 200°C, more preferably 40°C to 150°C, and even more preferably 50°C to 130°C, and particularly preferably 60°C to 110°C.

[0232] like Figure 4 As shown in (VI), to harden the filled, colorless resin composition layer 3 for embedding, active energy rays such as ultraviolet light or electron beams, or heat, can be used. Heating-based hardening, which minimizes uneven or insufficient irradiation, is particularly preferred. The heating temperature is preferably a temperature that allows for rapid hardening and also suppresses shrinkage of the water vapor barrier layer 4, preferably 60°C to 250°C, more preferably 70°C to 200°C, further preferably 80°C to 150°C, and most preferably 90°C to 120°C. When hardening the colorless resin composition layer 3 for embedding, hardening can be carried out under pressure as in step (V), or it can be carried out without special pressure.

[0233] By hardening the colorless resin composition layer filled between or around the light-emitting elements 7, and then embedding the hardened part 3' of the colorless resin composition layer 3 and the water vapor barrier layer 4 to seal the sealing object β1, a component 8 sealed with multiple light-emitting elements 7 can be obtained.

[0234] Alternatively, the sealing object β2 can be prepared by embedding at least a portion of the depth direction of the gaps between the light-emitting elements 7 in the sealing object β1 and / or at least a portion of the bottom surface of the gaps using the method described above. Figure 10 (1-a)~ Figure 10 (3-d)), used with Figure 4 (I-1) Figure 4 In the same case as (VII), a sealing layer forming sheet 1 is prepared separately, such as Figure 5 (I-1) Figure 8 As shown in (VII), the object β2 is sealed by embedding the hardened layer 3' of the colorless resin composition layer 3 and the water vapor barrier layer 4, thereby obtaining a component 8 sealed with multiple light-emitting elements.

[0235] Furthermore, the sealing object β3 can also be prepared by embedding the hardened part 9' of the colored resin composition 9 into the gaps between the light-emitting elements 7 in the sealing object β1, up to the height of the light-emitting elements 7, using the method described above. Figure 10 (1-a)~ Figure 10 (3-d)), used with Figure 4 (I-1) Figure 4 In the same case as (VII), a sealing layer forming sheet 1 is prepared separately, such as Figure 9 (I-1) Figure 9 As shown in (VII), the object β3 is sealed by embedding the hardened layer 3' of the colorless resin composition layer 3 and the water vapor barrier layer 4, thereby obtaining a component 8 sealed with multiple light-emitting elements 7.

[0236] [Example]

[0237] The present disclosure is described in detail below through examples and comparative examples, but the present disclosure is not particularly limited to the examples. In addition, unless otherwise specified, "parts" and "%" in the following description refer to "parts by mass" and "% by mass", respectively.

[0238] 1. Raw materials and properties of the resin composition layer

[0239] • [Preparation of a solution of resin (A)]

[0240] Manufacturing Example 1 [Manufacturing Example of (Meth)acrylic Resin (α-1) Solution]

[0241] A reaction vessel (hereinafter simply referred to as the "reaction vessel") including a stirrer, thermometer, reflux cooling tube, dropping device, and nitrogen inlet tube was loaded with 80 parts ethyl acetate, 25 parts methyl methacrylate, 73 parts n-butyl methacrylate, 2 parts acrylic acid, and 0.1 parts 2,2'-azobisisobutyronitrile (2,2'-Azobisisobutyronitrile) as an initiator. The atmosphere inside the reaction vessel was purged with nitrogen. Then, under a nitrogen atmosphere, the mixture was heated to 65°C with stirring. After polymerization at this temperature for 4 hours, glycidyl methacrylate, in an amount equivalent to half the carboxyl group of the acrylic acid, was added, and the mixture was stirred at 60°C for 24 hours. After the reaction was completed, the mixture was cooled and diluted with ethyl acetate to obtain a solution of (meth)acrylic resin (α-1) with a weight average molecular weight (Mw) of 100,000, a glass transition temperature (Tg) of 50°C, and a solids content of 50%.

[0242] In addition, the weight-average molecular weight (Mw), Tg, refractive index, water vapor transmission rate, moisture absorption rate, and elastic modulus at 100°C are determined by the methods described later.

[0243] Manufacturing Example 2 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-2)]

[0244] The amount of 2,2'-azobisisobutyronitrile was changed to 0.3 parts. Otherwise, polymerization was carried out in the same manner as in Manufacturing Example 1. After polymerization, glycidyl methacrylate was reacted with the carboxyl group of acrylic acid in the same manner as in Manufacturing Example 1 to produce a solution of (meth)acrylic resin (α-2) with a weight average molecular weight (Mw) of 50,000, a Tg of 46°C, and a solid content of 50%.

[0245] Manufacturing Example 3 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-3)]

[0246] The amount of 2,2'-azobisisobutyronitrile was changed to 0.05 parts. Otherwise, polymerization was carried out in the same manner as in Manufacturing Example 1. After polymerization, glycidyl methacrylate was reacted with the carboxyl group of acrylic acid in the same manner as in Manufacturing Example 1 to produce a solution of (meth)acrylic resin (α-3) with a weight average molecular weight (Mw) of 220,000, a Tg of 52°C, and a solid content of 50%.

[0247] Manufacturing Example 4 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-4)]

[0248] The monomer formulation was set to 30 parts methyl methacrylate, 64 parts n-butyl methacrylate, and 6 parts acrylic acid. The initiator was changed to 0.05 parts 2,2'-azobisisobutyronitrile. Otherwise, polymerization was carried out in the same manner as in Manufacturing Example 1. After polymerization, half of the glycidyl methacrylate was reacted with respect to the carboxyl group of acrylic acid in the same manner as in Manufacturing Example 1 to produce a solution of (meth)acrylic resin (α-4) with a weight average molecular weight (Mw) of 220,000, a Tg of 55°C, and a solid content of 50%.

[0249] Manufacturing Example 5 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-5)]

[0250] The monomer formulation was set to 25 parts methyl methacrylate, 68 parts n-butyl methacrylate, 2 parts acrylic acid, and 5 parts 2-(dimethylamino)ethyl acrylate. The initiator was changed to 0.15 parts 2,2'-azobisisobutyronitrile. Otherwise, polymerization was carried out in the same manner as in Manufacturing Example 1. After polymerization, half of the glycidyl methacrylate was reacted with respect to the carboxyl group of acrylic acid in the same manner as in Manufacturing Example 1 to produce a solution of (meth)acrylic resin (α-5) with a weight average molecular weight (Mw) of 110,000, a Tg of 47°C, and a solid content of 50%.

[0251] Manufacturing Example 6 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-6)]

[0252] After polymerization, glycidyl methacrylate does not react with the carboxyl group. Otherwise, polymerization is carried out in the same manner as in Manufacturing Example 1 to obtain a solution of (meth)acrylic resin (α-6) with a weight average molecular weight (Mw) of 100,000, a Tg of 48°C, and a solid content of 50%.

[0253] Manufacturing Example 7 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-7)]

[0254] The monomer was prepared in the same manner as in Manufacturing Example 1. The monomer was prepared in the same manner as in Manufacturing Example 1. After polymerization, glycidyl methacrylate was reacted with the carboxyl group of acrylic acid in the same manner as in Manufacturing Example 1 to obtain a solution of (meth)acrylic resin (α-7) with a weight average molecular weight (Mw) of 200,000, a Tg of -17°C, and a solid content of 50%.

[0255] Manufacturing Example 8 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-8)]

[0256] A reaction vessel (hereinafter simply referred to as the "reaction vessel") comprising a stirrer, thermometer, reflux cooling tube, dropping device, and nitrogen inlet tube was loaded with 80 parts ethyl acetate, 22 parts n-butyl acrylate, 76 parts n-butyl methacrylate, 2 parts acrylic acid, and 0.1 parts 2,2'-azobisisobutyronitrile (2,2'-azobisisobutyronitrile) as an initiator. The atmosphere inside the reaction vessel was purged with nitrogen. The vessel was then heated to 65°C under a nitrogen atmosphere with stirring and the reaction was initiated. Glycidyl methacrylate, equivalent to half the number of carboxyl groups of acrylic acid, was then added using the same method as in the preparation of (meth)acrylic resin (α-1), and the reaction was carried out at 65°C for 4 hours. After the reaction was completed, the vessel was cooled and diluted with ethyl acetate to obtain a solution of (meth)acrylic resin (α-8) with a weight average molecular weight (Mw) of 200,000, a Tg of 10°C, and a solid content of 50%.

[0257] Manufacturing Example 9 [Manufacturing Example of a Solution of (Meth)acrylic Resin (α-9)]

[0258] The monomers were prepared in the following proportions: 25 parts methyl methacrylate, 58 parts n-butyl methacrylate, 15 parts N-vinyl-2-pyrrolidone (hereinafter also referred to as NVP), 2 parts acrylic acid, and 0.1 parts 2,2'-azobisisobutyronitrile (2,2'-azobisisobutyronitrile). Otherwise, the reaction was initiated by heating to 65°C under a nitrogen atmosphere with stirring, as in Manufacturing Example 1. The reaction solution was then allowed to react at 65°C for 4 hours. After the reaction was stopped and cooled, it was diluted with ethyl acetate to obtain a solution of (meth)acrylic resin (α-9) with a weight average molecular weight (Mw) of 100,000, a Tg of 46°C, and a solid content of 50%.

[0259] • [Other transparent resin solutions]

[0260] •β-1 Polyester resin (VYLON 200, Mw: 20,000, Tg: 67℃) was mixed with toluene at a ratio of 1:1 to obtain a polyester resin solution with a solid content of 50%.

[0261] • β-2 polyurethane resin (POLISIC UP, Mw: 60000, Tg: 20℃, manufactured by Sanyo Chemical Co., Ltd.)

[0262] • β-3 was dissolved in a rubber-based resin (styrene-ethylene-propylene polymer: SEPTON 2063, Mw: 120,000, Tg: 65°C, manufactured by Kuraray Corporation) by adding toluene, dissolving it at 60°C using a disperser, and then returning to room temperature to obtain a rubber-based resin solution with a solid content of 20%. Furthermore, the Mw or Tg of the resin was determined in the same manner as in the case of resin (α-1).

[0263] • [Initiator (C)]

[0264] • C-1: Di-tert-butyl peroxide (10-hour half-life temperature: 123℃)

[0265] C-2: 1,1-Di(tert-butylperoxide)cyclohexane (10-hour half-life temperature: 84℃)

[0266] • [hardener]

[0267] •C-3: Polyisocyanate (manufactured by Asahi Kasei, Durnate TPA100, hexamethylene diisocyanate (HDI) urea ester, 100% solids)

[0268] [Other Additives U]

[0269] [Example of manufacturing dispersion (U-1)]

[0270] 95 parts of alumina AKP-G07 manufactured by Sumitomo Chemical (manufactured by Mitsubishi Chemical Corporation), 10 parts of resin (α-1) solution with 50% solids content, and 400 parts of methyl ethyl ketone as solvent were mixed and pre-dispersed using a disperser. Then, a formal dispersion was carried out for 2 hours using a 0.6L Dieno mill filled with 1800g of zirconia beads with a diameter of 0.3mm. After removing the zirconia beads, a dispersion of alumina with 20% solids content (U-1) was obtained.

[0271] (U-2) Carbamate acrylate oligomer Mw: 1500 6 functional

[0272] • (U-3) Carbamate acrylate oligomer Mw: 3000 3 functional

[0273] • (U-4) Ethyleneimine (P1000, manufactured by Japan Catalyst)

[0274] (U-5)N-Vinyl-2-pyrrolidone (manufactured by Tokyo Chemical Industry)

[0275] [Weight-average molecular weight (Mw)]

[0276] The weight-average molecular weight (Mw) of resin (A) and the like was calculated by using the GPC "LC-GPC system" manufactured by Shimadzu Corporation and converting it with polystyrene, whose molecular weight is known, as a standard substance.

[0277] Device Name: Shimadzu Corporation, LC-GPC System "Prominence"

[0278] The tubing is made by connecting four GMHXL tubings manufactured by Tosoh and one HXL-H tubing manufactured by Tosoh.

[0279] Mobile phase solvent: Tetrahydrofuran

[0280] Flow rate: 1.0 mL / min

[0281] Column temperature: 40℃

[0282] [Glass transition temperature (Tg: the temperature at which tanδ reaches its maximum value)]

[0283] The resin solutions obtained in each manufacturing example were coated onto the release surface of the release film and dried at 100°C for 2 minutes to prepare resin sheets with a thickness of 50 μm. The obtained sheets were cut into 0.5 cm × 2 cm pieces, and the release film was peeled off as samples for measurement. Dynamic viscoelasticity was measured using a DVA-200 / L2 dynamic viscoelasticity measuring device (manufactured by IT Measurement & Control Co., Ltd.) at a frequency of 10 Hz, a measurement temperature range of -50°C to 150°C, a heating rate of 5°C / min, and in tensile mode. The stored elastic modulus, loss elastic modulus, and loss tangent (tanδ) were plotted. The peak temperature (maximum tanδ) of the loss tangent (tanδ) was read from the obtained curves.

[0284] 2. Manufacturing and properties of the colorless resin composition layer [CR] for embedding

[0285] [CR-1]~[CR-5]

[0286] As shown in Table 1, 0.3 parts of initiator C-1 were added to 200 parts of a solution of resin (α-1) to resin (α-5) with a solid content of 50%, and then methyl ethyl ketone was added with a solid content of 40%. The resulting solution was applied to the release treatment surface of the first film FA-1, which was cut into 15 cm squares, using a dressing applicator. The solution was then treated in a drying oven at 80°C for 5 minutes to remove the solvent, thereby obtaining colorless resin composition layers [CR-1] to [CR-5] with a thickness of 10 μm. The determination of the Tg or refractive index of the resin composition layers will be described later. The formulations in the table are expressed in terms of solid content.

[0287] [CR-6]

[0288] As shown in Table 1, 200 parts of a solution of resin (α-6) with 50% solid content and 1 part of curing agent C-3 were used. Otherwise, a 10 μm thick colorless resin composition layer [CR-6] for embedding was formed on the first film FA-1 in the same manner as the resin composition layer [CR-1].

[0289] [CR-7]~[CR-25], [CR-101]~[CR-107]

[0290] According to the formulations shown in Tables 2 to 4 (expressed as solid components), colorless resin composition layers for embedding are formed respectively.

[0291] Table 1. Colorless resin composition layers for embedding

[0292]

[0293]

[0294]

[0295]

[0296] [Glass transition temperature (Tg: the temperature at which tanδ reaches its maximum value)]

[0297] Each layer of the resin composition for embedding is peeled off from the first membrane FA-1, and the Tg of the resin composition layer is measured in the same manner as in the case of resin (α-1).

[0298] [thickness]

[0299] The overall thickness of the first film FA-1 and each colorless resin composition layer for embedding disposed on the first film FA-1 was measured using a thickness gauge (manufactured by Mitutoyo, measuring part size: 10mm, measuring force: 1.0N). The thickness of each colorless resin composition layer for embedding was obtained by subtracting the thickness of the first film FA-1 from the measured value.

[0300] [Refractive Index]

[0301] The following values ​​are used as the refractive index, which are obtained by measuring the surface of each embedding resin composition layer disposed on the first film FA-1 using a prism coupler (Metricon 2010M) at 25°C and 50% RH at a measurement wavelength of 594 nm.

[0302] Water vapor transmission rate

[0303] <Colorless resin composition layer for embedding>

[0304] The colorless resin composition layer for embedding is difficult to separate, so the water vapor permeability is determined as follows. That is, for the entire first film FA-1 and each colorless resin composition layer provided on the first film FA-1, a water vapor permeability measuring device: C390H manufactured by Labthink is used. The surface in contact with water vapor during the measurement is set to the surface of the colorless resin composition layer side. At a permeation area of 5 cm 2 under the measurement conditions of 40 °C and 90% RH, the value P [g / (m 2 ·day)] of the water vapor permeability 24 hours after the start of the measurement is read. In addition, for the first film FA-1, the value P2 [g / (m 2 ·day)] of the water vapor permeability is measured under the same conditions. The value P3 [g / (m 2 ·day)] of the water vapor permeability of the colorless resin composition layer is calculated according to the following formula.

[0305] P3 = |P × P2| / |P2 - P|

[0306] [Moisture absorption rate]

[0307] Each resin composition layer for embedding is cut into a square with a side length of 5 cm together with the first film FA-1. The first film FA-1 side is placed on a stainless steel plate and left standing at 80 °C for 120 minutes. Then, it is taken out to an environment of 23 °C and 50% RH. After 15 minutes, the mass is measured in this environment. Then, it is left standing in an environment of 40 °C and 90% RH for 24 hours for moisture absorption, and then taken out to an environment of 23 °C and 50% RH. After 15 minutes, the mass is measured in this environment. According to the mass change before and after moisture absorption, the moisture absorption rate is calculated based on the following formula. In addition, when measuring the mass, the value rounded to the third decimal place after rounding the fourth decimal place is recorded.

[0308] Moisture absorption rate (%) = [(mass after moisture absorption ÷ mass before moisture absorption) - 1] × 100

[0309] [Elastic modulus at 100 °C (Pa)]

[0310] When measuring the Tg of the resin composition layer, the value at 100 °C of the storage elastic modulus plotted is read as the elastic modulus at 100 °C.

[0311] [b value]

[0312] Each resin composition layer for embedding is peeled off from the first film FA-1 and laminated onto a glass plate. Together with the glass plate, it is measured in transmission mode using a color difference meter (ZE6000 manufactured by Nippon Denshoku Industries Co., Ltd., light source: D60), and the b value is read.

[0313] [Haze]

[0314] Each resin composition layer for embedding was peeled from the first film FA-1 and laminated onto a glass plate at room temperature. The glass plate and the layer together were then measured and evaluated using a haze meter (NDH8000 manufactured by Nippon Lighting Co., Ltd., light source: D60). Furthermore, since the b-value and haze of the glass plate itself are extremely small, the values ​​obtained by measuring the glass plate together were used as the values ​​of each resin composition layer for embedding.

[0315] 3. Determination and physical properties of the water vapor barrier layer

[0316] <Water vapor barrier layer SB>

[0317] <SB-1~SB-6>

[0318] Cycloolefin resin was fed into a plastomill manufactured by Toyo Seiki, which has a 25mm wide T-die with a fish-mouth shape at the front end, at a barrel temperature of 230°C. Under the conditions of T-die temperature of 220°C, ejection rate of 10g / min, T-die clearance of 30μm, and winding speed of 2m / min, a cycloolefin film with a thickness of 7μm and a width of 20cm was obtained.

[0319] Furthermore, two widths are cut relative to the flow direction of the membrane (longitudinal direction (Machine Direction, MD)) and perpendicular to it (transverse direction (TD)) to obtain a 15cm square cycloolefin membrane with a thickness of 7μm: SB-1.

[0320] Under the same temperature and ejection conditions, the winding speed was slowed down and the gap of the T-die was widened to obtain cycloolefin films with thicknesses of 10 μm: SB-2, 13 μm: SB-3, 20 μm: SB-4, 30 μm: SB-5, and 50 μm: SB-6.

[0321] <SB-7>, <SB-101~SB-103>

[0322] For 100g of urethane acrylate (Mw: 2000, 10 functional), 1g of initiator ESACURE ONE (manufactured by DKSH) and 50g of methyl ethyl ketone were mixed using a disperser to prepare a coating solution.

[0323] The coating solution was applied to the release membrane using a dressing applicator to achieve a dry thickness of 30 μm. It was then dried at 80°C for 3 minutes using a high-pressure mercury lamp at 80 W / cm². 2The power was used to harden it, resulting in a 30 μm thick urethane acrylate hardened film on the release film: SB-7.

[0324] In addition, by changing the number of the dressing device during application, hardened films of urethane acrylate with thicknesses of 20 μm: SB-101, 15 μm: SB-102, and 10 μm: SB-103 were obtained.

[0325] ·SB-104: Biaxially oriented polypropylene (OPP) film, 20μm thick (manufactured by Naniwa Paper Industry, OPP sheet)

[0326] ·SB-105: Polyethylene terephthalate (PET) film, 12μm thick

[0327] ·SB-106: Alumina vapor-deposited PET film, 12μm thick (Barrialox manufactured by Toray Industries)

[0328] Under the same apparatus and conditions as in the case of the resin composition layer for embedding, the refractive index, water vapor transmission, moisture absorption, b-value, and HAZE were measured.

[0329] In addition, for SB-1 to SB-7, the release film was peeled off, and the water vapor barrier layer was separated and measured. The refractive index and water vapor transmittance of each water vapor barrier layer are shown in Table 5.

[0330] Table 5. Water vapor barrier layer

[0331]

[0332] 4. Fabrication and physical properties of the sealing layer sheet

[0333] [First film FA]

[0334] • FA-1 Kobatech RF 40TLGN (manufactured by Kobayashi Corporation), thickness 40μm, Ra: 0.14μm, Rδc: 0.21μm

[0335] • FA-2 Kobatech RF 40TLSN (manufactured by Kobayashi), thickness 40μm, Ra: 0.31μm, Rδc: 0.50μm

[0336] • FA-3 Kobatech RF 40TLMN (manufactured by Kobayashi Corporation), thickness 40μm, Ra: 1.10μm, Rδc: 1.52μm

[0337] • FA-4 Cosmopeel E7002 (manufactured by Toyobo Co., Ltd.), thickness 50μm, Ra: 0.01μm, Rδc: 0.03μm

[0338] • FA-5PG7H (manufactured by Contract Resin Industries), thickness 50μm, Ra: 2.73μm, Rδc: 4.41μm

[0339] <Surface roughness Ra, cut-off level difference Rδc of profile curve>

[0340] The surface roughness Ra of the first membrane is obtained by arithmetically averaging the absolute values ​​of the deviations between the centerline of the extracted portion and the roughness curve, taken from a portion of the roughness curve along its centerline. The cut-off level difference Rδc of the profile curve is the horizontal difference in the height direction within the roughness curve that coincides with any two load length rates, defined as 25% and 75%.

[0341] Specifically, the roughness curve is calculated as follows: Measurement data is acquired using a laser microscope (Keyence VK-X100). This data is then input into analysis software (the analysis application "VK-H1XA" equipped with the Japanese Industrial Standards (JIS) B0601:2013 surface property measurement module "VK-H1XR", both manufactured by Keyence), and JIS B0601:2013 surface property measurement is performed. To derive the roughness curve from the measured profile curve obtained through the measurement, a λc profile curve filter to remove short wavelengths such as noise and a λs profile curve filter to remove long wavelengths such as fluctuations are used. Depending on the surface condition to be measured, in the surface roughness measurement of analytical applications, any one of the following can be selected to measure the surface roughness Ra and the cut-off level difference Rδc of the profile curve: λs profile curve filter set to 2.5 μm, λc profile curve filter set to 0.8 mm, λs profile curve filter set to 8 μm, λc profile curve filter set to 2.5 mm, or λs profile curve filter set to 25 μm, λc profile curve filter set to 8 mm.

[0342] [Second Membrane FB]

[0343] • FB-1 is a micro-adhesive film (60μm thick, LE951 manufactured by Toyo Chemical) with an acrylic micro-adhesive layer on one side of a polyester film. Its elastic modulus at 100°C is 1.2 × 10⁻⁶. 9 Pa

[0344] • FB-2 polyester film (50μm thickness, manufactured by Toray, Lumirror #50), elastic modulus at 100°C: 9.8 × 10⁻⁶ 8 Pa

[0345] • FB-3 is a micro-adhesive film (50 μm thick, manufactured by Sun A. Kaken, PAC3-50) with an elastic micro-adhesive layer on one side of a polyethylene film. Its elastic modulus at 100°C is 1.9 × 10⁻⁶. 7 Pa

[0346] • FB-4 is a micro-adhesive film (50 μm thick, manufactured by NIPPA, OPP-SD3) with a silicone-based micro-adhesive layer on one side of a polypropylene membrane. Its elastic modulus at 100°C is 2.1 × 10⁻⁶. 8 Pa

[0347] [Example 1]

[0348] A 10 μm thick colorless resin composition layer CR-1 for embedding is formed on the first membrane FA-1. Then, the colorless resin composition layer CR-1 and the water vapor barrier layer SB-2 are laminated at 80°C to obtain a sealing layer precursor. Next, the water vapor barrier layer SB-2 and the micro-adhesive layer side of the second membrane FB-1 are laminated at room temperature to obtain a sealing layer forming sheet SH-1.

[0349] The first film FA-1 and the second film FB-1 are peeled off from the sealing layer forming sheet SH-1. Under the specified apparatus and conditions, the HAZE, b-value, water vapor transmission rate, and moisture absorption rate of the sealing layer precursor are determined. Furthermore, when determining the moisture absorption rate, the water vapor barrier layer is brought into contact with the stainless steel plate. Additionally, the total light transmittance is measured and evaluated using a haze meter (NDH8000 manufactured by Nippon Lighting Industry Co., Ltd., light source: D60) in the same manner as the HAZE.

[0350] [Examples 2-25], [Comparative Examples 101-107]

[0351] As shown in Tables 6 to 8, the colorless resin composition layer for embedding is set to any one of CR-7 to CR-25, CR-101 to CR-107, and the water vapor barrier layer is set to SB-1 or SB-2. Otherwise, the sealing layer forming sheets are obtained in the same manner as in Example 1.

[0352] [Examples 26 to 29]

[0353] When forming the colorless resin composition layer CR-1 for embedding, FA-2 to FA-5 are used instead of the first film FA-1, and SB-1 is used as the water vapor barrier layer. Otherwise, the sealing layer forming sheet is obtained in the same manner as in Example 1.

[0354] [Examples 30-32]

[0355] An embedding colorless resin composition layer CR-1 is formed on the first membrane FA-1, SB-1 is used as a water vapor barrier layer, and FB-2 to FB-4 are used instead of FB-1 as a second membrane. Otherwise, a sealing layer forming sheet is obtained in the same manner as in Example 1.

[0356] [Examples 33-38], [Comparative Examples 107-112]

[0357] An embedding colorless resin composition layer CR-1 is formed on the first membrane FA-1. SB-3 to SB-7 and SB-101 to SB-106 are used instead of SB-2 as water vapor barrier layers. FB-1 is used as the second membrane. Otherwise, sealing layer forming sheets are obtained in the same manner as in Example 1.

[0358] [Comparative Examples 113-115]

[0359] Comparative Example 113 is a sealing layer forming sheet with a laminated structure of first membrane FA-1 / embedded colorless resin composition layer CR-1 / second membrane FB-2 without a water vapor barrier layer; Comparative Example 114 is a sealing layer forming sheet with a laminated structure of first membrane FA-1 / embedded colorless resin composition layer CR-1 / water vapor barrier layer SB-1 without a second membrane; Comparative Example 115 is a sealing layer forming sheet with a laminated structure of first membrane FA-1 / water vapor barrier layer SB-1 / second membrane FB-2 without an embedded colorless resin composition layer.

[0360] [evaluate]

[0361] For the sealing layer forming sheets obtained in each embodiment and comparative example, various properties were evaluated according to the following methods.

[0362] <Experimental substrate>

[0363] A 25mm x 25mm glass plate (Corning EAGLE XG alkali-free glass, refractive index: 1.50) has 10 roughly parallel grooves, each 100μm wide and 5μm deep, spaced 100μm apart, etched approximately in the center of one of its faces (see reference). Figure 11 (1)).

[0364] <LED Sealing Component Model>

[0365] Peel off the first film from the sealing layer forming sheet to expose the colorless resin composition layer for embedding, and place the colorless resin composition layer for embedding on the surface of the test substrate where the uneven portion is formed.

[0366] A 50 μm thick TPX (OPULENT X-44B, Tohcello, Mitsui Chemicals) and a 2.0 mm thick vinyl chloride membrane (Celeb T, Okamoto, Inc.) were sequentially placed on the second membrane as a buffer material, and pressed for 20 minutes at 5 MPa and 100°C. After pressing, the second membrane and buffer material were peeled off, and the mixture was left to stand at 150°C for 2 hours to harden the colorless resin composition layer used for embedding, resulting in a 25 mm square LED sealing component model.

[0367] Furthermore, since Comparative Example 115 does not have an embedding resin composition layer, the water vapor barrier layer is not in close contact with the test substrate, so it is impossible to fabricate an LED sealing component model.

[0368] [Embeddedness Evaluation]

[0369] From the water vapor barrier layer side, under a coaxial light source and at 100x magnification, ten grooves in the approximate central part of a 25mm square LED sealing component model were observed using a microscope. The embedding performance was evaluated based on the presence and number of voids smaller than 10μm caused by poor embedding. Furthermore, even a single void with a maximum diameter of 10μm or more was considered a fatal "float."

[0370] S: There are no gaps or "floats"; the entire recess is embedded.

[0371] A: There are 1 to 5 gaps, and there is no "floating".

[0372] B: There are 6 to 10 gaps, and no "floating".

[0373] C: There are more than 10 gaps, but no "floating".

[0374] D: There is more than one "floating" point.

[0375] Furthermore, since the second film was not laminated in Comparative Example 114, the melon peel reticulate marks caused by the shrinkage differences of each layer (the resin composition layer for embedding, the water vapor barrier layer, and the buffer material) during embedding appeared on the entire surface of the water vapor barrier layer, so no further evaluation was conducted.

[0376] [Evaluation of the smoothness of the top surface]

[0377] The top surface of the LED sealing component model, i.e., the surface of the water vapor barrier layer, was observed at 100x magnification using a laser microscope (Keyence VK-X3000) over a range of 5mm x 7mm. The line roughness of the observed image was measured at three arbitrary locations within a length of approximately 1mm in the direction orthogonal to the groove on the test substrate, and the average height was calculated. Furthermore, irregularities caused by foreign matter or other irregularities at 100μm intervals corresponding to the groove were excluded.

[0378] S: Average height is below 1.0μm

[0379] A: Average height is above 1.1μm, and unevenness is below 2.0μm.

[0380] B: Average height is above 2.1μm, and unevenness is below 3.0μm.

[0381] C: Average height is above 3.1μm, and unevenness is below 4.0μm.

[0382] D: Average height is above 4.1μm

[0383] [Migration Resistance]

[0384] The sealing layer forming sheet is cut into a size of 2.5cm in length and 4cm in width, and then the first film is peeled off to expose the colorless resin composition layer for embedding. This layer is then placed on an evaluation substrate on which comb-shaped electrodes (material: silver-plated copper foil, pattern spacing: 50μm, line width / line space (L / S) = 25μm / 25μm, length 2.5cm × width 5cm) are formed on a polyimide film.

[0385] A 50 μm thick TPX (OPULENT X-44B, Tohcello, Mitsui Chemicals) and a 2.0 mm thick vinyl chloride membrane (Celeb T, Okamoto, Inc.) were sequentially placed on the second membrane as a buffer material, and pressed at 5 MPa and 100°C for 20 minutes. After pressing, the second membrane and buffer material were peeled off, and the membrane was left to stand at 150°C for 2 hours to harden the colorless resin composition layer used for embedding, thus creating a test piece for evaluating migration resistance.

[0386] After applying a voltage of 30V or 50V to the test piece for 1,000 hours at 85°C and 85%RH, the surface resistance was measured at room temperature (23°C) using a resistivity meter (Hiresta UX) with the probe touching the water vapor barrier surface of the sealing layer. The number of leakage contacts during the 1,000 hours was then confirmed. Furthermore, a "leakage contact" refers to an insulation breakdown caused by a short circuit, resulting in a momentary drop in resistance and the flow of current. The absence of leakage contacts indicates that the insulation has not deteriorated.

[0387] S: Resistance value is 1×10 8 Ω or higher, and there is no leakage contact.

[0388] A: Resistance value is less than 1×10 8 Ω and is 1×10 7 Ω or higher, and there is no leakage contact.

[0389] B: Resistance value is less than 1×10 8 Ω and is 1×10 7 Ω or higher, and leakage contact once.

[0390] C: Resistance value is less than 1×10 7 Ω and is 1×10 6 The current is above Ω and there are fewer than three leakage contacts.

[0391] D: Resistance value is less than 1×10 6 Ω or more than four leakage contacts.

[0392] The evaluation under the 30V application condition envisions the use of displays in a wide range of regions, including temperate, subarctic, frigid, and arid zones. The evaluation under the 50V application pressure condition further envisions the use of displays in tropical regions. In either case, S is best suited for forming high-power large displays of 50 inches or more, A is suitable for forming large displays, B can be used for forming general-purpose displays of less than 50 inches, C is limited to forming small displays of less than 10 inches, and D is unsuitable.

[0393] [Resistance to yellowing]

[0394] Using a colorimeter CR-300 (manufactured by Konica Minolta), and following the method described in JIS-Z8722, the b* values ​​(measured from the water vapor barrier layer side) of the LED sealing component model were calculated before and after a heating test at 110°C for 500 hours, expressed in L*a*b* colorimeters. The difference Δb* value was used to evaluate the resistance to yellowing.

[0395] Furthermore, measurements were conducted under transmission conditions when the total light transmittance of the LED sealing component model was above 70%, and under reflection conditions when the total light transmittance was below 70%.

[0396] Δb* value = b* value after heating test - b* value before heating test

[0397] S: Δb* value is less than 0.3.

[0398] A: The value of Δb* is greater than 0.3 and less than 0.5.

[0399] B: The value of Δb* is greater than 0.5 and less than 1.0.

[0400] C: Δb* value is greater than 1.0 and less than 1.5.

[0401] D: Δb* value is 1.5 or higher.

[0402] S is suitable for use with transparent displays, A is suitable for use with displays other than transparent displays, B can be used in a general form, C can be used in a limited way, and D cannot be used.

[0403] [Invisibility of boundary areas, etc.]

[0404] Prepare four LED sealing component models. Mark a white X mark in the center of the bottom surface of a black plastic shell (a SEKISEI Gran storage case) with a depth of 23mm × length of 146mm × width of 70mm. Inside the shell, as shown... Figure 11 As shown in (1), the model is arranged with two pieces closely joined in each direction, in a position where each side of the model is as parallel as possible to each side of the shell. At this time, the intersection of the four pieces of the model is set at the position marked by the white mark. Figure 11 (1) is a top view (schematic) with four of the models arranged on the housing.

[0405] Next, silicone oil (Shin-Etsu Silicone X-48-1800, refractive index 1.51) is injected until it exceeds 3mm to 5mm relative to the top surface of the model, impregnating the entire model.

[0406] Under fluorescent light, such as Figure 11 As shown in (2), from the center of the short side of the shell, at an angle of 45° and 50 cm away from the white mark, three random people peered at the model from the short side of the shell to confirm whether the boundaries between the models or the surrounding area of ​​the model were visible, and evaluated as follows. The lowest evaluation among the three people was used.

[0407] S: I don't know if a four-piece model exists.

[0408] A: It can be seen that the boundary lines of the four models are parallel to the short side of the shell. Apart from this, the existence of the four models is unknown.

[0409] B: Among the boundary lines of the four models, the boundary lines parallel to the long and short sides of the shell are visible in a cross shape.

[0410] C: Not only can the cross-shaped dividing line be seen, but the outer perimeter of the four models can also be seen.

[0411] D: The cross-shaped boundary line and the outer perimeter of the four models are visible, as are the upper surfaces of the four models.

[0412] S is suitable for use in transparent displays; A is suitable for limited use in transparent displays; B is suitable for use in high-definition colored displays; C is suitable for use in general colored displays; D is not suitable for use.

[0413]

[0414]

[0415]

[0416]

[0417]

[0418] Table 11. Sheets for forming sealing layers

[0419]

Claims

1. A sealing layer forming sheet for burying the light-emitting elements of a display that uses multiple light-emitting elements as light sources between each other, and covering the side of the surface from which the light of the multiple light-emitting elements is emitted. The sealing layer forming sheet is sequentially provided with a first film (2), a sealing layer precursor (α), and a second film (5). The water vapor permeability of the sealing layer precursor (α) is less than 100 g / (m 2 [24 hours], moisture absorption rate is less than 1.5% by mass. The sealing layer precursor (α) has a refractive index of 1.51 ± 0.03 and a water vapor permeability of 100 g / (m 2 • 24 hours) or more of colorless resin composition layer (3) for embedding, and a refractive index of 1.53 ± 0.03 and a water vapor transmission of less than 100 g / (m 2 Water vapor barrier layer (4) for 24 hours.

2. The sheet for forming a sealing layer according to claim 1, wherein, The water vapor barrier layer (4) is a thermoplastic olefin film.

3. The sheet for forming a sealing layer according to claim 1, wherein, The tensile storage modulus E'3 of the colorless resin composition layer (3) for embedding at 100°C (100) The tensile storage elastic modulus E'4 of the water vapor barrier layer (4) (100) The tensile storage elastic modulus E'5 of the second membrane (5) (100) The following relationship must be satisfied. E'4 (100) / E'3 (100) The range is 100 to 1000, and E'5 (100) / E'4 (100) It ranges from 0.5 to 3.

4. The sheet for forming a sealing layer according to claim 1, wherein, The total light transmittance of the sealing layer precursor (α) is above 85%.

5. A component sealed with a plurality of light-emitting elements, comprising a substrate and a plurality of light-emitting elements spaced apart and mounted on the substrate. At least a portion of the depth direction of the gaps between the light-emitting elements is composed of a refractive index of 1.51 ± 0.03 and a water vapor transmittance of 100 g / (m²). 2 • The hardened material (3') of the colorless resin composition layer (3) for embedding (24 hours) or above is embedded. The side emitting light from multiple light-emitting elements is sequentially coated with the hardened material (3') of the colorless resin composition layer (3) and a material with a refractive index of 1.53 ± 0.03 and a water vapor transmittance of less than 100 g / (m 2 Water vapor barrier layer (4) covering (24 hours)].

6. The component sealed with a plurality of light-emitting elements according to claim 5, wherein, At least a portion of the depth direction of the gaps between the light-emitting elements and / or at least a portion of the bottom surface of the gaps are embedded by a hardened portion (9') of a colored resin composition layer (9) for embedding, and the remaining portions of the gaps between the light-emitting elements are embedded by a hardened portion (3') of a colorless resin composition layer (3) for embedding.

7. The component sealed with a plurality of light-emitting elements according to claim 5, wherein, The water vapor barrier layer (4) is a thermoplastic olefin film.

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