Integrated encapsulating sheet, light emitting type electronic component and producing method of the same

Abstract

To provide an integrated type sealing sheet capable of, while securing blackness, and holding light-shielding performance between light-emitting elements, preventing brightness loss and color irregularity of a display, a light-emitting type electronic component using the sheet and a producing method of the same.SOLUTION: The present invention relates to an integrated sealing sheet 1 for pressure bonding to a surface where multiple light-emitting elements 21, 22, and 23 are arranged on a substrate 20 of the substrate 2 with an element on which multiple light-emitting elements 21, 22, 23 are arranged, which includes a black-curable resin layer 10 that blocks light between the multiple light-emitting elements 21, 22, and 23, a transparent curable resin layer 11 that has higher light permeability than the black-curable resin layer 10, and a substrate layer 12 that supports the black-curable resin layer 10 and the transparent curable resin layer 11, stacked in this order. The total light transmittance of the black-curable resin layer 10 in its cured state is 1-20%.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an integrated encapsulating sheet, a light-emitting electronic component, and a method for manufacturing the same. [Background technology]

[0002] In recent years, displays using extremely small light-emitting diodes known as mini-LEDs or micro-LEDs have been attracting attention. There are two main methods known for using such extremely small light-emitting diodes in displays. One is to arrange a large number of light-emitting diodes on a substrate to form a backlight for an LCD and locally control the brightness of the backlight. The other is to have light-emitting diodes of each color (red, green, and blue) emit light and send that color's light to the viewer's eyes on a pixel-by-pixel basis.

[0003] Light-emitting diodes such as mini-LEDs or micro-LEDs are generally arranged on a substrate. When multiple light-emitting diodes (referred to as light-emitting elements) are arranged on a substrate, it is necessary to provide light shielding between adjacent light-emitting elements. As a method for providing light shielding between multiple light-emitting elements using a resin with a light-shielding function, for example, a method using a dry film is known (see Patent Document 1). A dry film is a film obtained by applying a light-shielding resin composition to a protective film and drying it.

[0004] When a dry film is pressed onto a substrate over multiple light-emitting elements, a light-shielding resin layer is formed not only in the gaps between the light-emitting elements but also on the upper surfaces (light-emitting surfaces) of the light-emitting elements. Under such circumstances, the resin layer may block light from reaching the viewer of the display. To prevent this, the above-mentioned conventional technology employs a method in which the light-emitting surface of the light-emitting element is etched using a plasma treatment or other etching method to remove the resin layer on the light-emitting surface, and then the removed surface is covered with a light-transmitting sealant. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-22562 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the above-mentioned conventional techniques require a long time for the etching process, which increases manufacturing costs. Furthermore, it is difficult to completely remove the resin layer on the light-emitting surface of the light-emitting element, making it difficult to completely prevent the diffusion of light that should reach the viewer side of the display. Furthermore, the etching process requires a step of laminating a highly transparent sealing film, which increases the number of manufacturing processes.

[0007] In view of the above problems, prior to the present invention, the present inventors developed an integrated encapsulating sheet in which one or more curable resin layers are formed on one surface of a film substrate. The inventors discovered that by press-bonding the integrated encapsulating sheet to a light-emitting element so that the curable resin layer side faces the light-emitting surface of the light-emitting element and curing the curable resin layer, it is possible to reduce light diffusion between light-emitting elements and realize a structure that does not block light emitted from the light-emitting element.

[0008] The all-in-one encapsulating sheet developed prior to the present invention as described above also has further improvements. The all-in-one encapsulating sheet has a configuration in which a light-shielding layer is filled between light-emitting elements by press-bonding, and a transparent layer can cover the light-emitting elements. However, multiple light-emitting elements on a substrate generally have different heights and inclinations, making it difficult to fill the light-emitting elements without leaving any light-shielding layer on the top surfaces. In particular, the light-shielding layer is likely to remain on light-emitting elements with low heights, resulting in differences in the degree of light-shielding layer remaining between light-emitting elements. If the light-shielding layer remains on the top surfaces of the light-emitting elements, this may result in a decrease in the brightness of the light-emitting elements. In this case, the light-shielding layer, if cured as is, may cause color unevenness and brightness loss when the display emits light.

[0009] Therefore, the present invention aims to provide an integrated encapsulating sheet that can ensure blackness, maintain light-shielding performance between light-emitting elements, and prevent brightness loss and color unevenness in the display, as well as a light-emitting electronic component using the sheet and a method for manufacturing the same. [Means for solving the problem]

[0010] (1) An integrated encapsulating sheet according to one embodiment for achieving the above object comprises: An integrated encapsulating sheet to be pressure-bonded to a surface of an element-mounted substrate on which a plurality of light-emitting elements are arranged, the surface comprising: a black cured resin layer that shields light between the plurality of light-emitting elements, a transparent cured resin layer that has higher light transmittance than the black cured resin layer, and a base layer that supports the black cured resin layer and the transparent cured resin layer, stacked in this order; The black curable resin layer has a total light transmittance of 1 to 20% in a cured state. (2) In the all-in-one encapsulating sheet according to another embodiment, preferably, the black curable resin layer may have a total light transmittance of 1 to 10% in a cured state. (3) In the all-in-one encapsulating sheet according to another embodiment, preferably, the black curable resin layer in a cured state may have a total light transmittance of 2.35% or more and less than 5%. (4) In the all-in-one encapsulating sheet according to another embodiment, preferably, the transparent curable resin layer may have a total light transmittance of 70 to 99% in a cured state. (5) In the all-in-one encapsulating sheet according to another embodiment, preferably, the storage modulus at 100°C of the transparent curable resin layer may be larger than the storage modulus at 100°C of the black curable resin layer. (6) In the integrated encapsulating sheet according to another embodiment, preferably, the storage modulus of the transparent curable resin layer at 100°C is 1.0 × 10 7 It may be less than Pa. (7) In the integrated encapsulating sheet according to another embodiment, preferably, the black curable resin layer has a storage modulus at 100°C of 1.0 × 10 5It may be less than Pa. (8) In the integrated encapsulating sheet according to another embodiment, preferably, the black curable resin layer and the transparent curable resin layer contain a curable resin composition, and the curable resin composition may contain an epoxy resin. (9) In the all-in-one encapsulating sheet according to another embodiment, the transparent curable resin layer may preferably contain an epoxy resin having a weight average molecular weight of 10,000 or more. (10) In the one-piece encapsulating sheet according to another embodiment, preferably, the black curable resin layer may contain an elastomer. (11) In the all-in-one encapsulating sheet according to another embodiment, preferably, the base material layer may further include a hard coat layer on a surface opposite to the surface in contact with the transparent curable resin layer. (12) To achieve the above object, a light-emitting electronic component according to one embodiment comprises: an element-mounted substrate having a plurality of light-emitting elements arranged on the substrate; an integrated encapsulating cured sheet that is pressure-bonded to a surface of the element-mounted substrate on which the plurality of light-emitting elements are arranged, the integrated encapsulating cured sheet is made up of a black resin layer that shields light between the plurality of light-emitting elements, a transparent resin layer that has higher light transmittance than the black resin layer, and a base layer that supports the black resin layer and the transparent resin layer, laminated in this order from the side that contacts the element-mounted substrate; The black resin layer has a total light transmittance of 1 to 20%. (13) In another embodiment of the light-emitting electronic component, preferably, the thickness of the transparent resin layer is 0.1 to 5.0 times the height of the plurality of light-emitting elements; The thickness of the black resin layer may be 0.1 to 0.9 times the height of the plurality of light emitting elements. (14) In order to achieve the above object, a method for manufacturing a light-emitting electronic component according to one embodiment includes the steps of: A step of arranging any one of the integrated encapsulating sheets described above on a surface of an element-mounted substrate on which a plurality of light-emitting elements are arranged; filling the black cured resin layer and at least a portion of the transparent cured resin layer between the plurality of light-emitting elements; and curing the black curable resin layer and the transparent curable resin layer. [Effects of the Invention]

[0011] The present invention provides an integrated encapsulating sheet that can prevent brightness loss and color unevenness of a display while ensuring blackness and maintaining light-shielding performance between light-emitting elements, a light-emitting electronic component using the sheet, and a method for manufacturing the same. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 shows a cross-sectional view of an integrated encapsulating sheet according to one embodiment when cut in the thickness direction. [Figure 2] FIG. 2 shows a cross-sectional view seen in the same manner as FIG. 1 when the integrated encapsulating sheet of FIG. 1 is arranged so that the black curable resin layer thereof is in contact with the top surface of the light emitting element of the element-mounted substrate. [Figure 3] FIG. 3 shows a cross-sectional view, seen from the same perspective as FIG. 1, of a state in which the integrated encapsulating sheet has been pressure-bonded to the element-mounted substrate, proceeding from the stage shown in FIG. 2 up to the state in which the black curable resin layer and the transparent curable resin layer shown in FIG. 1 are embedded between the light-emitting elements. [Figure 4] FIG. 4 shows a cross-sectional view similar to FIG. 1, showing a state after the stage shown in FIG. 3, in which the protective sheet on the base layer has been peeled off and a curing treatment has been carried out. [Figure 5] FIG. 5 shows a cross-sectional view taken in the same direction as FIG. 1 of an integrated encapsulating sheet according to another embodiment. [Figure 6] FIG. 6 shows a cross-sectional view taken in the same direction as FIG. 1 of a light-emitting electronic component according to another embodiment manufactured using the integrated encapsulating sheet of FIG. DETAILED DESCRIPTION OF THE INVENTION

[0013] Next, embodiments of the present invention will be described with reference to the drawings. Note that the embodiments described below do not limit the invention according to the claims, and not all of the elements and combinations thereof described in the embodiments are necessarily essential to the solution of the present invention. In this application, "main component" means a component that accounts for 50% by mass or more of the total solid content of the entire composition. In this application, "total resin solid content" means the total solid mass of the resin and elastomer, and if a curing agent is blended in addition to the elastomer, it also includes the solid mass of the curing agent. A numerical range expressed by "to" means a numerical range with the numbers before and after "to" as the lower and upper limits.

[0014] (First embodiment) Fig. 1 shows a cross-sectional view of an integrated encapsulating sheet according to one embodiment when cut in the thickness direction. Fig. 2 shows a cross-sectional view, as seen from Fig. 1, of the integrated encapsulating sheet of Fig. 1 when the black curable resin layer is placed in contact with the top surface of the light-emitting element of the element-mounted substrate. Fig. 3 shows a cross-sectional view, as seen from Fig. 1, of a state in which the integrated encapsulating sheet has been pressure-bonded to the element-mounted substrate up to a state in which the black curable resin layer and the transparent curable resin layer of Fig. 1 are embedded between the light-emitting elements, proceeding from the stage of Fig. 2. Fig. 4 shows a cross-sectional view, as seen from Fig. 1, of a state in which the protective sheet on the base material layer has been peeled off and a curing treatment has been performed, proceeding further from the stage of Fig. 3.

[0015] 1. Integrated encapsulating sheet The integrated encapsulating sheet 1 according to the present embodiment is an integrated encapsulating sheet 1 to be pressure-bonded to a surface of an element-mounted substrate 2 on which a plurality of light-emitting elements 21, 22, and 23 are arranged, the surface being formed by pressure bonding the light-emitting elements 21, 22, and 23 to the surface of the element-mounted substrate 2, in which the light-emitting elements 21, 22, and 23 are arranged. The integrated encapsulating sheet 1 includes a black cured resin layer 10 that blocks light from passing between the light-emitting elements 21, 22, and 23, a transparent cured resin layer 11 that has higher light transmittance than the black cured resin layer 10, and a base material layer 12 that supports the black cured resin layer 10 and the transparent cured resin layer 11, laminated in this order. In the present application, the phrase "laminated in this order" does not necessarily mean that the integrated encapsulating sheet 1 has these layers laminated continuously without any intervening layers, and various functional layers may be provided between the layers. The functional layer may be any of the layers described below or any other known functional layer. Furthermore, when the functional layer is laminated on the integrated encapsulating sheet 1, the functional layer may be a cured layer or an uncured layer.

[0016] The integrated encapsulating sheet 1 is in a state before a curing process of an integrated encapsulating cured sheet 3 provided in a light-emitting electronic component 5, which will be described later. The integrated encapsulating sheet 1 is a laminate in which at least a black curable resin layer 10, a transparent curable resin layer 11, and a base material layer 12 are laminated in this order. In the arrangement process and the filling process, which will be described later, the surface of the integrated encapsulating sheet 1 on the black curable resin layer 10 side is pressure-bonded to a plurality of light-emitting elements 21, 22, and 23. In addition, the black curable resin layer 10 and the transparent curable resin layer 11 are in an uncured state until a curing process, which will be described later, is performed. That is, the black curable resin layer 10 and the transparent curable resin layer 11 are cured in the curing process to become a black resin layer 30 and a transparent resin layer 31.

[0017] In the present application, "light transmittance" refers to light transmittance measured by various known methods, such as total light transmittance measured using a haze meter in accordance with JIS K 7361-1. In the present application, the total light transmittance of the black curable resin layer 10 and the transparent curable resin layer 11 in their cured states, as described below, is a value obtained as follows. For example, in the case of the total light transmittance of the black curable resin layer 10 in its cured state, first, the total light transmittance of the protective sheet 13 alone, as described below, is measured using a haze meter (e.g., NDH5000 manufactured by Nippon Denshoku Industries Co., Ltd.) in accordance with JIS K 7361-1. Next, a laminate sheet is prepared in which the cured black curable resin layer 10 (i.e., the black resin layer 30) is laminated on the protective sheet 13, and the total light transmittance of the laminate sheet is measured in the same manner. From the total light transmittance of the obtained laminate sheet, a value excluding the influence of the protective sheet 13 is calculated, and this value is defined as the total light transmittance of the black curable resin layer 10 in its cured state. In addition, the total light transmittance of the transparent curable resin layer 11 in a cured state can be obtained in a similar manner by changing the black curable resin layer 10 and the protective sheet 13 to the transparent curable resin layer 11 and the substrate layer 12 described below, respectively.

[0018] (L* value of integrated encapsulant sheet) The L* value of the one-piece encapsulant sheet 1 is measured from the side of the base material layer 12 (or the hard coat layer 15, described later, when the hard coat layer 15 is provided) in accordance with JIS Z 8781-4, using a light source D65, a field of view of 2°, a reflection method, and an SCE method. The L* value is preferably less than 30, more preferably less than 26, even more preferably less than 24, and particularly preferably less than 23. The measurement of the L* value is performed on a standard white calibration plate. Since the light transmittance of the black curable resin layer 10 in the one-piece encapsulant sheet 1 is low, there is almost no influence of the standard white calibration plate. When the L* value is less than the upper limit, the blackness when the display is turned off can be increased. The measurement of the L* value is preferably performed in a state where the sheet is not arranged or filled on the element-mounted substrate 2.

[0019] For ease of handling, the integrated encapsulating sheet 1 may further include a protective sheet on the outer surface of either or both of the black curable resin layer 10 and the substrate layer 12. FIG. 1 shows an example of the integrated encapsulating sheet 1 in which protective sheets 13, 14 are provided on the outer surfaces of both the black curable resin layer 10 and the substrate layer 12. More specifically, the integrated encapsulating sheet 1 has a structure in which the protective sheet 14, the substrate layer 12, the transparent curable resin layer 11, the black curable resin layer 10, and the protective sheet 13 are laminated in this order. Each layer constituting the integrated encapsulating sheet 1 will be described below.

[0020] (1) Black curable resin layer The black curable resin layer 10 is a layer for blocking light between the light-emitting elements 21, 22, and 23. It also serves to improve the contrast of the display. The black curable resin layer 10 is also a layer for sufficiently filling the spaces between the multiple light-emitting elements 21, 22, and 23 arranged on the element-mounted substrate 2 by a method such as thermocompression bonding in the arrangement step and filling step, and is also a layer for preventing poor appearance due to expansion of unfilled gaps in the curing step such as thermal curing, and damage to the light-emitting elements 21, 22, and 23 due to external factors in subsequent steps.

[0021] [Black pigment or black dye] To enhance light-blocking properties, the black curable resin layer 10 may contain a black pigment or black dye as a colorant, preferably a black pigment. The black pigment may preferably contain carbon black, titanium oxide, iron oxide, or the like, more preferably carbon black. These colorants are contained in the curable resin composition described below.

[0022] As the carbon black, one or more types of known carbon black such as gas black, channel black, furnace black, thermal black, and lamp black can be used. Resin-coated carbon black may also be used. Furthermore, carbon nanofibers and carbon nanotubes may also be used.

[0023] Among the above carbon blacks, gas black is preferred because it has many surface functional groups and high dispersibility, and therefore exhibits sufficient light-blocking properties even when added in a small amount. Furthermore, when the black curable resin layer 10 contains a modified elastomer having functional groups reactive with epoxy resins, the dispersibility is further enhanced due to the interaction between the surface functional groups of the gas black and the functional groups of the modified elastomer having functional groups reactive with epoxy resins, thereby ensuring good light-blocking properties and coating liquid stability.

[0024] The amount of carbon black blended is preferably 0.05 to 15 mass %, more preferably 0.1 to 5 mass %, and even more preferably 0.3 to 1.25 mass %, relative to 100 mass % of the total resin solids content of the black curable resin layer 10. When the amount of carbon black blended is equal to or greater than the above lower limit, sufficient light-blocking properties can be obtained. When the amount of carbon black blended is equal to or less than the above upper limit, the thixotropy of the black curable resin layer 10 can be reduced, and the fluidity of the black curable resin layer 10 during thermocompression bonding can be increased. This allows the black curable resin layer 10 to sufficiently fill the spaces between the multiple light emitting elements 21, 22, and 23 of the element-mounted substrate 2.

[0025] [L*a*b* value] The L*a*b* values of the black curable resin layer 10 in a cured state, as measured in accordance with JIS Z 8781-4:2013 using a D65 light source, a 2° field of view, a reflection method, and the SCE method, are preferably L*: 0 to 30, a*: -10 to 10, and b*: -20 to 20, and more preferably L*: 1.5 to 30, a*: -5 to 5, and b*: -15 to 15. The L*a*b* values are measured using a standard white calibration plate. Because the light transmittance of the black curable resin layer 10 is low, the influence of the standard white calibration plate is minimal. By ensuring that the L*a*b* values in the cured state are within the preferred range, the black curable resin layer 10 can, after curing, shield light from the light-emitting elements 21, 22, and 23, thereby further improving the contrast of the display. The same indices apply to the uncured black curable resin layer 10.

[0026] [Total light transmittance] The total light transmittance of the black curable resin layer 10 in a cured state is lower than the total light transmittance of the transparent curable resin layer 11 (described later) in a cured state. Specifically, the total light transmittance of the black curable resin layer 10 in a cured state is adjusted to 1 to 20%, preferably 1 to 10%, more preferably 1.5 to 5%, even more preferably 2 to 5%, and particularly preferably 2.35% or more and less than 5%. A total light transmittance of 20% or less ensures concealment after curing. A total light transmittance of 10% or less allows the black curable resin layer 10 to achieve light shielding between the light-emitting elements 21, 22, and 23 after curing. This light shielding prevents interference between the light-emitting elements, thereby reducing color unevenness during display emission. A total light transmittance of 5% or less ensures high levels of blackness when the display is not emitting light and reduces color unevenness during emission. Furthermore, since the lower limit of the total light transmittance is 1% or more, even if the black curable resin layer 10 remains on the top surfaces of the multiple light-emitting elements 21, 22, and 23 during the filling and curing process, the light-blocking performance between the light-emitting elements 21, 22, and 23 is maintained and the light-emitting elements 21, 22, and 23 do not interfere with light emission toward the viewer. Consequently, color unevenness and brightness loss can be suppressed when the display emits light. The total light transmittance of the black curable resin layer 10 in a cured state can be changed mainly by the presence or absence of a black pigment or black dye, or the amount of black pigment or black dye added. It can also be changed by the thickness of the black curable resin layer 10 and the type of resin composition.

[0027] [Storage modulus] The storage modulus of the black curable resin layer 10 in an uncured state is preferably smaller than the storage modulus of the transparent curable resin layer 11 in an uncured state. The storage modulus of the black curable resin layer 10 in an uncured state at 100° C. is preferably 1.0×10 5 Pa or less, and more preferably 1.0×10 1 ~1.0×10 5 Pa, and even more preferably 1.0×10 2 ~5.0×10 4 It is Pa.

[0028] Since the storage modulus of the black curable resin layer 10 is equal to or less than the preferred upper limit at 100°C, the black curable resin layer 10 exhibits sufficient fluidity when pressed onto the element-mounted substrate 2, and can follow the unevenness of the element-mounted substrate 2 caused by the plurality of light-emitting elements 21, 22, 23, and sufficiently fill the spaces between the plurality of light-emitting elements 21, 22, 23.

[0029] When the storage modulus of the black curable resin layer 10 is equal to or greater than the preferred lower limit at 100°C, uneven pressure during thermocompression bonding of the black curable resin layer 10 can be prevented, and a uniform degree of blackness can be maintained even if the black curable resin layer 10 remains on the top surfaces of multiple light-emitting elements 21, 22, and 23 during the filling and curing process due to differences in the height or inclination of the light-emitting elements. In addition, outflow of the resin outside a predetermined range can be prevented, ensuring a film thickness after compression bonding.

[0030] The storage modulus of the black curable resin layer 10 in an uncured state at 150° C. is preferably 5.0×10 5 Pa or less, and more preferably 5.0 × 10 2 ~5.0×10 5 Pa, and even more preferably 1.0×10 3 ~1.0×10 5 It is Pa.

[0031] When the storage modulus of the black curable resin layer 10 at 150° C. is equal to or less than the preferred upper limit, cracks due to cure shrinkage during thermal curing are less likely to occur.

[0032] When the storage modulus of the black curable resin layer 10 is equal to or greater than the preferred lower limit at 150° C., flow during thermal curing can be suppressed, and poor appearance after curing, such as repellency, can be suppressed.

[0033] [Curable resin composition] The black curable resin layer 10 includes a curable resin composition. An example of the curable resin composition is a curable resin composition containing at least one resin selected from epoxy resin, acrylic resin, polyester resin, polyurethane resin, and silicone resin, and a curing agent. Among the above curable resin compositions, an epoxy resin composition that can be cured at low temperatures and has excellent heat resistance and reliability is preferred. In this specification, an epoxy resin composition refers to a composition containing an epoxy resin as a main component, or a composition containing an epoxy resin and a curing agent as main components.

[0034] When the black curable resin layer 10 contains an epoxy resin composition, it may contain a curing agent for epoxy resins other than the modified elastomer having a functional group reactive with an epoxy group. Examples of other curing agents include known curing agents such as phenol-based curing agents, acid anhydride-based curing agents, and amine-based curing agents. Two or more of the other curing agents may be used in combination.

[0035] (epoxy resin) In this application, an epoxy resin is a compound having an epoxy group in the molecule. The epoxy resin used in the present invention is preferably one having two or more epoxy groups in one molecule. This is because a crosslinked structure is formed by reaction with a modified resin having a functional group reactive with the epoxy group, and the cured product can exhibit high heat resistance. Furthermore, when an epoxy resin having two or more epoxy groups is used, the degree of crosslinking with a curing agent having a functional group reactive with the epoxy group is sufficient, and sufficient heat resistance can be obtained in the cured product.

[0036] Examples of epoxy resins include bifunctional epoxy resins having two epoxy groups per molecule, multifunctional epoxy resins having three or more epoxy groups per molecule, and high-molecular-weight epoxy resins having a weight-average molecular weight of 10,000 or more. These may also be hydrogenated epoxy resins. In this application, epoxy resins having a weight-average molecular weight of 10,000 or more are not classified as bifunctional or multifunctional epoxy resins, but as high-molecular-weight epoxy resins, regardless of the number of epoxy groups per molecule. The weight-average molecular weight of an epoxy resin is the molecular weight in terms of polystyrene measured by gel permeation chromatography.

[0037] Examples of epoxy resins include bisphenol-based epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, or phenoxy resins obtained by polymerizing these resins, and hydrogenated versions of these resins; novolac type epoxy resins such as phenol novolac epoxy resin, o-cresol novolac epoxy resin, bisphenol A novolac epoxy resin, xylene structure-containing novolac epoxy resin, and naphthol novolac type epoxy resin; glycidyl ester-based epoxy resins such as phthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-hydroxybenzoic acid glycidyl ester, tetrahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, and trimellitic acid triglycidyl ester; ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycidyl ether-based epoxy resins such as glycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tetraglycidyl ether, tetraphenylglycidyl ether ethane, triphenylglycidyl ether ethane, polyglycidyl ether of sorbitol, and polyglycidyl ether of polyglycerol; glycidylamine-based epoxy resins such as triglycidyl isocyanurate and tetraglycidyldiaminodiphenylmethane; linear aliphatic epoxy resins such as epoxidized polybutadiene and epoxidized soybean oil; and special skeleton epoxy resins such as brominated bisphenol A-type epoxy resins, phosphorus-containing epoxy resins, fluorine-containing epoxy resins, dicyclopentadiene skeleton-containing epoxy resins, naphthalene skeleton-containing epoxy resins, anthracene-type epoxy resins, tertiary butylcatechol-type epoxy resins, triphenylmethane-type epoxy resins, tetraphenylethane-type epoxy resins, biphenyl-type epoxy resins, and bisphenol S-type epoxy resins, but are not limited to these.

[0038] Examples of high molecular weight epoxy resins that can be used include phenoxy resin, epoxy-modified polybutadiene, copolymers of glycidyl methacrylate and methyl methacrylate, modified polymers obtained by epoxy-modifying other resins, etc. These epoxy resins may be used alone or in combination of two or more.

[0039] Among the above epoxy resins, polyfunctional epoxy resins are preferred as the epoxy resin used in the black curable resin layer 10 from the viewpoint of increasing the crosslink density after curing. Among polyfunctional epoxy resins, novolac-type epoxy resins are particularly preferred for the following reasons. Novolac-type epoxy resins are epoxy resins that can be appropriately introduced with a flexible skeleton, allowing for adjustment of flexibility and softening point. This makes the cured product less susceptible to brittle fracture, improving the performance stability of the cured product of the epoxy resin composition over long-term use and increasing the crosslink density. Additionally, the heat resistance of the cured product is also improved.

[0040] Specific examples of novolac-type epoxy resins include "YX7700" manufactured by Mitsubishi Chemical Corporation, "NC7000L", "XD1000", and "EOCN-1020" manufactured by Nippon Kayaku Co., Ltd., "ESN485" manufactured by Nippon Steel Chemical & Material Co., Ltd., and "N-660", "N-690", "N-695", and "HP-7200H" manufactured by DIC Corporation.

[0041] The blending amount of the polyfunctional epoxy resin in the black curing resin layer 10 is preferably 10 to 99 mass%, more preferably 40 to 95 mass%, and even more preferably 60 to 90 mass%, relative to 100 mass% of the total resin solid content of the black curing resin layer 10. When the blending amount is equal to or greater than the lower limit, the crosslinking density can be increased, thereby imparting chemical resistance and heat resistance. When the blending amount is equal to or less than the upper limit, the storage modulus during thermocompression bonding can be adjusted, thereby ensuring the fluidity of the black curing resin layer 10.

[0042] The black curable resin layer 10 preferably does not contain a high-molecular-weight epoxy resin. This makes it easier to ensure sufficient fluidity of the black curable resin layer 10 during thermocompression bonding. When the black curable resin layer 10 contains a high-molecular-weight epoxy resin, the blending amount of the high-molecular-weight epoxy resin is preferably less than 50% by mass, more preferably less than 30% by mass, and even more preferably less than 10% by mass, relative to 100% by mass of the total resin solid content of the black curable resin layer 10.

[0043] From the viewpoint of ensuring sufficient fluidity during thermocompression bonding, the black curable resin layer 10 preferably contains an epoxy resin having a softening point or melting point of 100° C. or less. From the viewpoint of handleability and heat resistance of the cured product, the black curable resin layer 10 more preferably contains an epoxy resin having a softening point or melting point of 40 to 95° C. By containing an epoxy resin having a softening point or melting point within the above range, it becomes easier to control the storage modulus of the black curable resin layer 10.

[0044] The total amount of epoxy resin in the black curing resin layer 10 is preferably 10 to 100% by mass, more preferably 20 to 99% by mass, and even more preferably 35 to 95% by mass, relative to 100% by mass of the total resin solids content of the black curing resin layer 10. Within this range, it is easy to control the storage modulus of the black curing resin layer 10, and appropriate fluidity during thermocompression bonding can be ensured. Furthermore, when the amount is equal to or greater than the above lower limit, the heat resistance of the black curing resin layer 10 after curing can be improved.

[0045] (Elastomer) The black curable resin layer 10 preferably contains an elastomer in addition to a resin such as an epoxy resin. The inclusion of an elastomer facilitates control of the storage modulus of the black curable resin layer 10, i.e., control of the fluidity. This prevents uneven pressure during thermocompression bonding of the black curable resin layer 10, and maintains a uniform blackness even when the black curable resin layer 10 remains on the top surfaces of multiple light-emitting elements 21, 22, and 23 during the filling and curing process due to differences in the height or inclination of the light-emitting elements.

[0046] As the elastomer, a thermosetting elastomer, commonly called "rubber," is preferred because it provides excellent heat resistance. Examples of thermosetting elastomers include acrylonitrile butadiene rubber (NBR), which is a random copolymer of butadiene and acrylonitrile, acrylic rubber, styrene butadiene rubber, vinyl acetate resin, and silicone resin. Among these, NBR is preferred. NBR has good compatibility with epoxy resins, making it easy to control the fluidity of the black curable resin layer 10 at around 100°C, resulting in good adhesion between the black curable resin layer 10 and the transparent curable resin layer 11 and the element-mounted substrate 2.

[0047] The weight-average molecular weight of the elastomer is preferably 100,000 to 1,000,000, more preferably 120,000 to 500,000, and even more preferably 150,000 to 300,000. When the weight-average molecular weight of the elastomer is within the above range, the storage modulus of the black curable resin layer 10 can be easily controlled, and fluidity during thermocompression bonding can be ensured. When the weight-average molecular weight of the elastomer is equal to or less than the above upper limit, compatibility between the elastomer and the epoxy resin is improved, and fluidity during thermal curing of the black curable resin layer 10 can be more effectively controlled.

[0048] In particular, when the black curable resin layer 10 contains an epoxy resin composition, it preferably contains a modified elastomer having a functional group reactive with an epoxy group. The modified elastomer having a functional group reactive with an epoxy group also functions as a curing agent for the epoxy resin. Furthermore, because the modified elastomer can react and bond with the epoxy resin, the heat resistance and thermal shock resistance of the cured black curable resin layer 10 are improved. Furthermore, the difference in polarity between the functional group reactive with the epoxy resin and the resin skeleton favorably affects dispersibility, resulting in good dispersibility when carbon black is added to the black curable resin layer 10.

[0049] Examples of functional groups that can react with epoxy groups include acid groups such as carboxy groups, sulfo groups, nitro groups, and phosphate groups, as well as their acid anhydride groups, hydroxyl groups, and amino groups. Among these, acid groups and acid anhydride groups are preferred because they allow curing at low temperatures and ensure a long usable time. For the same reasons, carboxy groups and carboxylic acid anhydride groups are particularly preferred.

[0050] That is, when the black curable resin layer 10 contains an epoxy resin composition, it preferably contains an acid-modified elastomer having an acid group or an acid anhydride group, more preferably contains an acid-modified elastomer having a carboxy group, and even more preferably contains modified NBR having a carboxy group.

[0051] The modified NBR having a carboxy group is preferably a carboxylated acrylonitrile rubber into which acrylic acid, methacrylic acid, maleic anhydride, etc. have been introduced. Commercially available carboxylated acrylonitrile rubbers include "NX775" and "1072CGJ" manufactured by Zeon Corporation. Two or more modified elastomers having a functional group reactive with an epoxy group may be used in combination.

[0052] The amount of elastomer in the black curable resin layer 10 is preferably 0.01 to 90% by mass, more preferably 1 to 80% by mass, and even more preferably 5 to 65% by mass, relative to 100% by mass of the total resin solids content of the black curable resin layer 10. Within this range, the storage modulus of the black curable resin layer 10 can be easily controlled, ensuring appropriate fluidity of the black curable resin layer 10 during thermocompression bonding. Ensuring this fluidity prevents uneven pressure during thermocompression bonding of the black curable resin layer 10. Even if the black curable resin layer 10 remains on the top surfaces of multiple light-emitting elements 21, 22, and 23 during the filling and curing process due to differences in the height or inclination of the light-emitting elements, uniform blackness can be maintained. Furthermore, when the amount is equal to or greater than the above lower limit, the dispersibility of carbon black in the epoxy resin composition is improved. Furthermore, the film-forming properties of the epoxy resin composition are improved, narrowing the film thickness distribution when the epoxy resin composition is applied to form a film.

[0053] (hardening agent) When the black curable resin layer 10 contains an epoxy resin composition, it may contain a curing agent for epoxy resins other than the modified elastomer having a functional group reactive with an epoxy group. Examples of the other curing agent include known curing agents such as phenol-based curing agents, acid anhydride-based curing agents, and amine-based curing agents. Two or more of the other curing agents may be used in combination.

[0054] (curing catalyst) When the black curable resin layer 10 contains an epoxy resin composition, it may contain a curing catalyst that promotes the curing reaction of the epoxy resin. Examples of curing catalysts include imidazole-based, tertiary amine-based, and phosphorus compound-based catalysts. Among these, imidazole-based catalysts are preferred because they are compatible with epoxy resins and less likely to cause yellowing. Among imidazole-based curing catalysts, those containing a cyanoethyl group are particularly preferred because they are easily soluble in epoxy resins. The blending amount of the curing catalyst is preferably 0.01 to 5 mass%, more preferably 0.05 to 4 mass%, and even more preferably 0.1 to 3 mass%, relative to 100 mass% of the total resin solids content of the black curable resin layer 10. Within the above ranges, the curing of the black curable resin layer 10 can be sufficiently promoted, ensuring the usable life of the integrated encapsulating sheet 1. Two or more curing catalysts may be used in combination.

[0055] (Other ingredients) The black curable resin layer 10 may contain an inorganic filler to improve flame retardancy and heat resistance and to adjust the refractive index. If necessary, the black curable resin layer 10 may further contain a resin other than the epoxy resin and elastomer, a thickener, a defoaming agent and / or a leveling agent, an adhesion imparting agent such as a coupling agent, and a flame retardant.

[0056] (2)Transparent curable resin layer The transparent curable resin layer 11 is a layer for, during pressure bonding, sufficiently pressing the black curable resin layer 10 into spaces between the plurality of light-emitting elements 21, 22, and 23 arranged on the element-mounted substrate 2. The transparent curable resin layer 11 is formed between the black curable resin layer 10 and a base layer 12 described below.

[0057] [Total light transmittance] The total light transmittance of the transparent curable resin layer 11 in a cured state is higher than the total light transmittance of the black curable resin layer 10 in a cured state. The total light transmittance of the transparent curable resin layer 11 in a cured state is not particularly limited, and is preferably adjusted to be 50 to 99%, more preferably 60 to 99%, and even more preferably 70 to 99%.

[0058] [Storage modulus] The storage modulus of the transparent curable resin layer 11 in an uncured state is preferably greater than that of the black curable resin layer 10. Similarly, at 100°C and 150°C, the storage modulus of the transparent curable resin layer 11 is preferably greater than that of the black curable resin layer 10.

[0059] The storage elastic modulus of the transparent curable resin layer 11 is preferably greater than that of the black curable resin layer 10 at 100 to 150°C. When the storage elastic modulus of the transparent curable resin layer 11 is greater than that of the black curable resin layer 10 at 100°C and 150°C, the storage elastic modulus of the transparent curable resin layer 11 is usually greater than that of the black curable resin layer 10 over the entire temperature range of 100 to 150°C.

[0060] The storage modulus of the transparent curable resin layer 11 at 100° C. is preferably 1.0×10 3 ~1.0×10 7 Pa, and more preferably 5.0×10 3 ~6.0×10 5 It is Pa.

[0061] When the storage modulus of the transparent curable resin layer 11 is equal to or less than the preferred upper limit at 100°C, appropriate flexibility is obtained that does not hinder the flow of the black curable resin layer 10 when it is pressure-bonded to the element-mounted substrate 2. In addition, the spaces between the plurality of light-emitting elements 21, 22, and 23 can be sufficiently filled.

[0062] When the storage modulus of the transparent curable resin layer 11 is equal to or greater than the preferred lower limit at 100°C, the fluidity of the transparent curable resin layer 11 is suppressed, and the black curable resin layer 10 is pressed uniformly, thereby maintaining a uniform film thickness of the black curable resin layer 10. As a result, even if the black curable resin layer 10 remains on the top surfaces of the plurality of light-emitting elements 21, 22, and 23 during the filling and curing process due to differences in the height or inclination of the light-emitting elements, a uniform degree of blackness can be maintained.

[0063] The storage modulus of the transparent curable resin layer 11 at 150° C. is preferably 1.0×10 4 Pa or more, more preferably 1.0×10 4 ~5.0×10 7 Pa, and even more preferably 1.0×10 5 ~5.0×10 6 It is Pa.

[0064] When the storage modulus of the transparent curable resin layer 11 at 150° C. is equal to or less than the preferred upper limit, cracks due to cure shrinkage during thermal curing are less likely to occur.

[0065] When the storage modulus of the transparent curable resin layer 11 at 150° C. is equal to or greater than the preferred lower limit, flow and generation of bubbles and the like during thermal curing of the transparent curable resin layer 11 can be suppressed.

[0066] The storage elastic modulus of the transparent curable resin layer 11 at 100°C is preferably 10 to 1,000 times, and more preferably 30 to 500 times, the storage elastic modulus of the black curable resin layer 10. The storage elastic modulus of the transparent curable resin layer 11 at 150°C is preferably 5 to 10,000 times, and more preferably 10 to 1,000 times, the storage elastic modulus of the black curable resin layer 10. When the storage elastic modulus of the transparent curable resin layer 11 is higher than that of the black curable resin layer 10 at 100°C and 150°C, the storage elastic modulus of the transparent curable resin layer 11 is usually higher than that of the black curable resin layer 10 over the entire temperature range from 100 to 150°C.

[0067] [Curable resin composition] The transparent curable resin layer 11 contains a curable resin composition. As with the black curable resin layer 10, the curable resin composition can be, for example, a curable resin composition containing at least one resin selected from epoxy resin, acrylic resin, polyester resin, polyurethane resin, and silicone resin, and a curing agent. Among these, an epoxy resin composition is preferred because it can be cured at low temperature and has excellent heat resistance and reliability.

[0068] (epoxy resin) Examples of epoxy resins used in the transparent curable resin layer 11 include the same types as those used in the black curable resin layer 10. From the viewpoint of being able to impart an appropriate viscosity during compression bonding to the transparent curable resin layer 11, the transparent curable resin layer 11 preferably contains a high-molecular-weight epoxy resin having a weight-average molecular weight of 10,000 to 100,000. Furthermore, from the viewpoint of having good compatibility with other resin components and being able to dissolve without mixing with a high-boiling-point solvent that may remain in the integrated encapsulating sheet 1 even after drying, the transparent curable resin layer 11 more preferably contains a high-molecular-weight epoxy resin having a weight-average molecular weight of 10,000 to 35,000.

[0069] The transparent curable resin layer 11 contains a high-molecular-weight epoxy resin with a weight-average molecular weight of 10,000 to 100,000, and thus has an appropriate viscosity when heated. Therefore, the storage modulus of the transparent curable resin layer 11 at 100 to 150°C can be adjusted to a preferred range. The high-molecular-weight epoxy resin is preferably a phenoxy resin because of its good compatibility with other epoxy resins.

[0070] Phenoxy resin has a relatively large molecular weight among epoxy resins and has an appropriate viscosity when heated. Therefore, the storage modulus of the transparent curable resin layer 11 containing phenoxy resin can be adjusted within a preferred range within a temperature range of 100 to 150°C. Furthermore, unlike other thermoplastic resins such as polyester, phenoxy resin can be cured as an epoxy resin. Therefore, phenoxy resin increases crosslink density and does not impair the heat resistance of the cured product or the reliability of its performance over long periods of use. From the viewpoint of ensuring a storage modulus sufficient to compress the black curable resin layer 10 during thermocompression bonding, the glass transition temperature of the phenoxy resin used in the transparent curable resin layer 11 is preferably 100°C or higher.

[0071] Specific examples of phenoxy resins include "1256," "YX7200," "YX8100," and "YX7180" manufactured by Mitsubishi Chemical Corporation, "YP-50," "YP-50S," and "YP-70" manufactured by Nippon Steel Chemical & Material Co., Ltd., and "N-690," "H-157," and "EXA-192" manufactured by DIC Corporation.

[0072] The blending amount of the high molecular weight epoxy resin in the transparent curable resin layer 11 is preferably 30 to 80 mass %, more preferably 40 to 70 mass %, and even more preferably 45 to 60 mass %, relative to 100 mass % of the total resin solid content of the transparent curable resin layer 11. The same is true for the preferred blending amount of the phenoxy resin in the transparent curable resin layer 11.

[0073] When the blending amount is within the above range, it becomes easy to control the storage modulus. This ensures a storage modulus sufficient to compress the transparent curable resin layer 11 during thermocompression bonding. Furthermore, flow during thermal curing can be suppressed, and poor appearance after curing, such as repellency, can be suppressed. Furthermore, problems are less likely to occur when etching is performed in a subsequent process. Furthermore, toughness is improved, and crack-like defects are less likely to occur during thermocompression bonding. Furthermore, when the blending amount is equal to or less than the above upper limit, the crosslink density of the transparent curable resin layer 11 in the cured state can be increased, and heat resistance and chemical resistance can be improved.

[0074] Furthermore, the epoxy resin used in the transparent curable resin layer 11 preferably contains a multifunctional epoxy resin. The multifunctional epoxy resin increases the crosslink density, thereby further improving the stability of the performance of the cured product of the epoxy resin composition over long-term use and improving heat resistance. Furthermore, the viscosity of the multifunctional epoxy resin is lower than that of the phenoxy resin in the range of 100 to 150°C. Therefore, by combining the multifunctional epoxy resin with the phenoxy resin, the storage modulus of the transparent curable resin layer 11 can be adjusted.

[0075] Specific examples of polyfunctional epoxy resins include "YX7700," "157S70," and "1032S60" manufactured by Mitsubishi Chemical Corporation, "NC7000L," "XD1000," and "EOCN-1020" manufactured by Nippon Kayaku Co., Ltd., "ESN485" manufactured by Nippon Steel Chemical & Material Co., Ltd., and "N-660," "N-690," "N-695," and "HP-7200H" manufactured by DIC Corporation.

[0076] The blending amount of the polyfunctional epoxy resin in the transparent curable resin layer 11 is preferably 90% by mass or less, more preferably 10 to 80% by mass, and even more preferably 25 to 60% by mass, relative to 100% by mass of the total resin solid content of the transparent curable resin layer 11. Within the above ranges, the storage modulus of the transparent curable resin layer 11 during thermocompression bonding can be controlled, and heat resistance and chemical resistance can be imparted in the cured state.

[0077] From the viewpoint of ensuring sufficient fluidity during thermocompression bonding, the transparent curable resin layer 11 preferably contains an epoxy resin having a softening point or melting point of 120° C. or less, and from the viewpoint of handleability and heat resistance of the cured product, more preferably contains an epoxy resin having a softening point or melting point of 50 to 105° C. By containing an epoxy resin having a softening point or melting point within the above range, it becomes possible to control the storage modulus.

[0078] The total amount of epoxy resin in the transparent curable resin layer 11 is preferably 10 to 100% by mass, more preferably 30 to 99% by mass, and even more preferably 50 to 95% by mass, relative to 100% by mass of the total resin solids content of the transparent curable resin layer 11. Within this range, control of the storage modulus is easy. This ensures a storage modulus sufficient to compress the black curable resin layer 10 during thermocompression bonding. Furthermore, within this range, flow during thermal curing can be suppressed, and poor appearance after curing, such as repellency, can be suppressed. Furthermore, problems are less likely to occur when etching is performed in a subsequent step. Furthermore, if the amount is equal to or greater than the lower limit, heat resistance in the cured state is improved.

[0079] (Elastomer) The transparent curable resin layer 11 preferably contains an elastomer in addition to a resin such as an epoxy resin. The inclusion of an elastomer makes it easier to control the storage modulus. Examples of elastomers include the same types as those used for the black curable resin layer 10. Among them, NBR is preferred for the following reasons: NBR has good compatibility with epoxy resins. Furthermore, it can increase the storage modulus of the transparent curable resin layer 11 at around 150°C, thereby improving the adhesion between the transparent curable resin layer 11 and the black curable resin layer 10. The preferred weight-average molecular weight of the elastomer is the same as that of the black curable resin layer 10.

[0080] In particular, when the transparent curable resin layer 11 contains an epoxy resin composition, it preferably contains a modified elastomer having a functional group capable of reacting with an epoxy group. The modified elastomer also functions as a curing agent for the epoxy resin. Furthermore, because it reacts with and bonds to the epoxy resin, it improves heat resistance and reliability against thermal shock. Furthermore, the difference in polarity between the functional group and the resin backbone favorably affects dispersibility. This allows for favorable dispersibility when carbon black is incorporated into the transparent curable resin layer 11.

[0081] Examples of functional groups capable of reacting with an epoxy group include the same types as those of the black curable resin layer 10. Among them, an acid group or an acid anhydride group is preferred, and a carboxy group or a carboxylic acid anhydride group is particularly preferred, because they can be cured at low temperatures and ensure a long usable time.

[0082] When the transparent curable resin layer 11 contains an epoxy resin composition, it particularly preferably contains modified NBR having a carboxy group. Examples of modified NBR having a carboxy group include the same types as those used for the black curable resin layer 10. Two or more types of modified elastomers having a functional group reactive with an epoxy group may be used in combination.

[0083] The amount of elastomer in the transparent curable resin layer 11 is preferably 0 to 50% by mass, more preferably 1 to 50% by mass, and even more preferably 5 to 50% by mass, relative to 100% by mass of the total resin solids content of the transparent curable resin layer 11. Within this range, the storage modulus can be controlled. Furthermore, when the amount is equal to or less than the upper limit, a storage modulus sufficient to compress the black curable resin layer 10 during thermocompression bonding can be ensured. Furthermore, flow during thermal curing can be suppressed, and poor appearance after curing, such as repellency, can be suppressed. Furthermore, problems are less likely to occur when etching is performed in a subsequent process. Furthermore, when the amount is equal to or greater than the lower limit, the dispersibility of carbon black is improved. Furthermore, film-formability is improved, and the film thickness distribution can be narrowed when the epoxy resin composition is applied to form a film.

[0084] (hardening agent) When the transparent curable resin layer 11 contains an epoxy resin composition, it may contain, in addition to the modified elastomer having a functional group reactive with an epoxy group, other curing agents for epoxy resins. Examples of other curing agents include the same curing agents as those used in the black curable resin layer 10. Two or more types of other curing agents may be used in combination.

[0085] (curing catalyst) When the transparent curable resin layer 11 contains an epoxy resin composition, it may contain a curing catalyst that accelerates the curing reaction of the epoxy resin. Examples of the curing catalyst include the same curing catalysts as those used for the black curable resin layer 10, and preferred embodiments are also the same.

[0086] The blending amount of the curing catalyst is preferably 0.01 to 5 mass%, more preferably 0.05 to 4 mass%, and even more preferably 0.1 to 3 mass%, relative to 100 mass% of the total resin solid content of the transparent curable resin layer 11. Within the above range, curing can be sufficiently promoted, and the usable life of the integrated encapsulating sheet 1 can be ensured. Two or more types of curing catalysts may be used in combination.

[0087] (Other ingredients) The transparent curable resin layer 11 may contain a black pigment or black dye to suppress uneven light emission and uneven color.

[0088] When the transparent curable resin layer 11 contains carbon black, the amount of carbon black is preferably less than 5% by mass, more preferably 1% by mass or less, and even more preferably 0.1% by mass or less, relative to 100% by mass of the total resin solids. The transparent curable resin layer 11 may further contain, as necessary, a resin other than the epoxy resin and elastomer, a thickener, a defoamer and / or leveling agent, an adhesion promoter such as a coupling agent, and a flame retardant.

[0089] [Film thickness] The thickness of the transparent curable resin layer 11 is not particularly limited, but is preferably 10 to 250 μm, more preferably 20 to 225 μm, and even more preferably 25 to 150 μm.

[0090] (3) Base material layer The base layer 12 is a layer for protecting the plurality of light-emitting elements 21, 22, 23 from external physical impacts, humidity, moisture, etc. The base layer 12 also supports the black curable resin layer 10 and the transparent curable resin layer 11, and also serves as a base for forming layers such as the black curable resin layer 10, the transparent curable resin layer 11, and the hard coat layer 15 described below. The base layer 12 is a cured layer.

[0091] [Total light transmittance] The total light transmittance of the base layer 12 can be measured using a haze meter or the like in accordance with JIS K 7361-1. The total light transmittance of the base layer 12 is adjusted to be preferably 30 to 99%, more preferably 35 to 95%, and even more preferably 40 to 95%. When the total light transmittance of the base layer 12 is equal to or greater than the lower limit, light is not prevented from reaching the viewer's side.

[0092] [Storage modulus] The storage modulus of the base layer 12 at 60° C. is preferably 7×10 8 ~2×10 10 Pa, and more preferably 1×10 9 ~1×10 10 Pa, and even more preferably 2×10 9 ~6×10 9 Pa. When the storage modulus of the base layer 12 at 60° C. is equal to or less than the preferred upper limit, cracking of the base layer 12 can be reduced.

[0093] [resin] The substrate layer 12 may be composed of a thermoplastic resin or a thermosetting resin. Examples of resins that may be used for the substrate layer 12 include polyethylene terephthalate resin, polybutylene terephthalate resin, polyethylene 2,6-naphthalate resin, polyamide resin, polycarbonate resin, polycarbonate copolymer resin, triacetyl cellulose resin, polymethylpentene resin, phenoxy resin, syndiotactic polystyrene resin, and polyimide resin. In terms of heat resistance, weather resistance, availability, cost, and other factors, the substrate layer 12 preferably contains at least one resin selected from polyethylene terephthalate resin, polyethylene 2,6-naphthalate resin, polycarbonate resin, polycarbonate copolymer resin, and polyamide resin. The inclusion of these resins can prevent deformation during pressure bonding. The substrate layer 12 may also contain a black pigment or black dye to suppress uneven light emission and color.

[0094] [Film thickness] The thickness of the base material layer 12 is preferably 10 to 250 μm, more preferably 20 to 225 μm, and even more preferably 25 to 150 μm. When the thickness of the base material layer 12 is equal to or greater than the preferred lower limit, it is possible to suppress the occurrence of wrinkles when the integrated encapsulating sheet 1 is thermocompression bonded to the plurality of light emitting elements 21, 22, and 23, and also to improve the handleability. When the thickness of the base material layer 12 is equal to or less than the preferred upper limit, it is possible to improve the visibility and reduce the cost.

[0095] (4) Protective sheet The protective sheets 13 and 14 have a role of protecting the integrated encapsulating sheet 1. When the integrated encapsulating sheet 1 is formed, the protective sheet 13 can also be used as a sheet to which a coating liquid of a curable resin composition is applied.

[0096] The protective sheets 13 and 14 may be sheets made of thermoplastic resins such as polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyimide, polyamide-imide, polyethylene, polytetrafluoroethylene, polypropylene, and polystyrene, or surface-treated paper.

[0097] Among these, polyester sheets are preferred from the viewpoints of heat resistance, mechanical strength, ease of handling, etc. The thickness of the protective sheets 13, 14 is not particularly limited and may be selected appropriately depending on the application within the range of approximately 10 to 150 μm. The surface of the protective sheet 13 on which the black curable resin layer 10 is to be provided may be subjected to a release treatment.

[0098] 2. Manufacturing method of integrated encapsulating sheet To obtain the integrated encapsulating sheet 1, first, a protective sheet 13 is prepared by applying a coating liquid of a curable resin composition for the black curable resin layer 10 to the protective sheet 13 and drying the same (A), and a substrate layer 12 is prepared by applying a coating liquid of a curable resin composition for the transparent curable resin layer 11 to the substrate layer 12 and drying the same (B).

[0099] Thereafter, the above-mentioned (A) and (B) are laminated together so that the transparent curable resin layer 11 and the black curable resin layer 10 are in contact with each other, thereby obtaining a laminate in which the black curable resin layer 10, the transparent curable resin layer 11, and the base layer 12 are laminated in this order on the protective sheet 13. A protective sheet 14 may be laminated on the outer surface of the base layer 12, if necessary.

[0100] The coating liquid of the curable resin composition for the black curable resin layer 10 and / or the coating liquid of the curable resin composition for the transparent curable resin layer 11 preferably contains an organic solvent in an amount sufficient to achieve a viscosity that allows for smooth application. The organic solvent is not particularly limited, but examples thereof include ketones, aromatic hydrocarbons, glycol ethers, glycol ether acetates, esters, alcohols, aliphatic hydrocarbons, and petroleum-based solvents. Specific examples include ketones such as methyl ethyl ketone, cyclohexanone, methyl butyl ketone, and methyl isobutyl ketone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; ethyl acetate, butyl acetate, isobutyl acetate, ethylene glycol monomethyl ether, dipropylene glycol diethyl ether, and triethylene glycol monoethyl ether; and ethyl acetate, butyl acetate, isobutyl acetate, and ethyl acetate. Examples of suitable solvents include esters such as propylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, propylene glycol methyl ether acetate, propylene glycol ethyl ether acetate, and propylene glycol butyl ether acetate; alcohols such as ethanol, propanol, 2-methoxypropanol, n-butanol, isobutyl alcohol, isopentyl alcohol, ethylene glycol, and propylene glycol; aliphatic hydrocarbons such as octane and decane; petroleum solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha, as well as N,N-dimethylformamide (DMF), tetrachloroethylene, and turpentine. When incorporating carbon black into the coating liquid, carbon black powder may be added to the coating liquid, or a liquid in which carbon black has been previously dispersed (carbon black dispersion) may be added.

[0101] Examples of methods for applying the curable resin composition include methods using various coaters such as a die coater, gravure coater, roll coater, curtain flow coater, spin coater, bar coater, reverse coater, kiss coater, fountain coater, rod coater, air doctor coater, knife coater, blade coater, cast coater, screen coater, etc. The drying temperature is preferably 60 to 160°C, more preferably 80 to 130°C, and even more preferably 90 to 120°C.

[0102] The temperature during lamination is preferably 20 to 120°C, more preferably 30 to 100°C, and even more preferably 40 to 80°C. By setting the temperature at or above the preferred lower limit, it is possible to ensure adhesion between the black curable resin layer 10 and the transparent curable resin layer 11 that allows handling even in uncured states. Furthermore, by setting the temperature at or below the preferred upper limit, it is possible to prevent air bubbles from being trapped between the black curable resin layer 10 and the transparent curable resin layer 11 and the occurrence of wrinkles in the layers 10 and 11. Lamination can be performed using, for example, a roll laminator, a press, a vacuum press, or the like.

[0103] 3. Substrate with elements As shown in Fig. 2, the element-mounted substrate 2 has a plurality of light-emitting elements 21, 22, and 23 arranged on a substrate 20. Fig. 2 and other figures schematically show a portion where three light-emitting elements (light-emitting element 21, light-emitting element 22, and light-emitting element 23) are arranged.

[0104] There is no limitation on the material of the substrate 20, but known printed circuit boards can be suitably used, such as glass epoxy boards, fluororesin boards, ceramic boards, and glass boards.

[0105] The light-emitting elements 21, 22, and 23 are typically light-emitting diodes. This embodiment is particularly suitable for extremely small light-emitting elements 21, 22, and 23. For example, light-emitting diodes with a height of 1000 nm to 200 μm and a side length of 0.001 to 0.5 mm can be used. The element-mounted substrate 20 for obtaining mini LEDs or micro LEDs can use light-emitting diodes of three colors (R, G, and B) or blue light-emitting diodes as the light-emitting elements 21, 22, and 23. In this application, the "height of the light-emitting element" refers to the height of the light-emitting elements 21, 22, and 23 from the bottom surface that contacts the substrate 20 to the top surface. The heights of the multiple light-emitting elements 21, 22, and 23 on the substrate 20 do not all need to be the same; they may differ individually within the range of the machining accuracy of the element-mounted substrate 2.

[0106] 4. Light-emitting electronic components and manufacturing methods thereof The light-emitting electronic component 5 of this embodiment comprises an element-mounted substrate 2 having a plurality of light-emitting elements 21, 22, 23 arranged on a substrate 20, and an integrated encapsulating cured sheet 3 pressed against the surface of the element-mounted substrate 2 on which the plurality of light-emitting elements 21, 22, 23 are arranged.

[0107] The integrated encapsulating cured sheet 3 is formed by laminating, in this order from the side in contact with the element-mounted substrate 2, a black resin layer 30 that shields the spaces between the plurality of light-emitting elements 21, 22, and 23 and has a total light transmittance of 1 to 20%; a transparent resin layer 31 that has higher light transmittance than the black resin layer 30; and a base layer 12 that supports the black resin layer 30 and the transparent resin layer 31. The black resin layer 30 and the transparent resin layer 31 are cured layers obtained by thermally curing the black curable resin layer 10 and the transparent curable resin layer 11, respectively. That is, the integrated encapsulating cured sheet 3 is the sheet obtained by curing the black curable resin layer 10 and the transparent curable resin layer 11 of the integrated encapsulating sheet 1. Like the above-described integrated encapsulating sheet 1, the integrated encapsulating cured sheet 3 is not limited to an embodiment in which these layers are laminated continuously without any intervening layers, and various functional layers in a cured state may be provided between the layers.

[0108] The thickness of the transparent resin layer 31 is not particularly limited, but is preferably 0.1 to 5.0 times the height of the plurality of light-emitting elements 21, 22, and 23. The thickness of the black resin layer 30 is not particularly limited, but is preferably 0.1 to 0.9 times the height of the plurality of light-emitting elements 21, 22, and 23.

[0109] The total light transmittance of the black resin layer 30 is lower than that of the transparent resin layer 31. Specifically, the total light transmittance of the black resin layer 30 is 1 to 20%, preferably 1 to 10%, more preferably 1.5 to 5%, even more preferably 2 to 5%, and particularly preferably 2.35% or more and less than 5%. A total light transmittance of 20% or less ensures concealment. A total light transmittance of 10% or less allows the black resin layer 30 to block light between the light-emitting elements 21, 22, and 23, preventing interference between the light-emitting elements and thereby suppressing color unevenness during light emission of the display. A total light transmittance of 5% or less allows a high level of blackness to be maintained when the display is not emitting light and a high level of color unevenness to be suppressed during light emission. Furthermore, since the lower limit of the total light transmittance is 1% or more, even if the black resin layer 30 remains on the top surfaces of the plurality of light emitting elements 21, 22, 23, the light blocking performance between the light emitting elements 21, 22, 23 is maintained and the light emitting elements 21, 22, 23 are not prevented from emitting light toward the viewer. Consequently, color unevenness and brightness loss can be suppressed when the display emits light.

[0110] (Luminance transmittance) In the present application, the "luminance transmittance" refers to the transmittance calculated from the luminance of the light-emitting elements 21, 22, and 23 on the element-mounted substrate 2 before and after pressure-bonding of the cured sheet for integral encapsulation 3. Specifically, the luminance of the light-emitting elements 21, 22, and 23 on the element-mounted substrate 2 when lit (hereinafter also referred to as "pre-mounting luminance") before pressure-bonding of the cured sheet for integral encapsulation 3, and the luminance of the light-emitting electronic component 5 when lit (hereinafter also referred to as "post-mounting luminance") are measured. Then, the luminance transmittance is calculated by substituting each measured value into the following formula (I). That is, the luminance transmittance is calculated by dividing the value of the post-mounting luminance by the value of the pre-mounting luminance. The luminance transmittance is preferably 65% or more, more preferably 70 to 90%, and even more preferably 75 to 85%. Luminance transmittance (%) = (luminance after mounting / luminance before mounting) × 100 (I)

[0111] (brightness variation coefficient) In the present application, the "brightness variation coefficient" is determined by measuring the above-mentioned post-mounting brightness on the element-mounted substrate 2 for the plurality of light-emitting elements 21, 22, and 23, calculating the average value and standard deviation of those values, and substituting them into the following formula (II). That is, it is calculated by dividing the standard deviation by the average value. The variation coefficient is preferably 20% or less, more preferably 15% or less, even more preferably less than 13%, and particularly preferably less than 10%. A value of the variation coefficient equal to or less than the above upper limit indicates little brightness unevenness. Coefficient of variation of brightness (%) = (standard deviation of brightness after mounting / average brightness after mounting) x 100 (II)

[0112] The method for manufacturing a light-emitting electronic component according to the present embodiment includes the steps of: placing the black curable resin layer 10 side of the integrated encapsulating sheet 1 on the surface of the element-mounted substrate 2, on which the plurality of light-emitting elements 21, 22, 23 are arranged, and starting pressure bonding (hereinafter referred to as the placing step); continuing pressure bonding to fill the spaces between the plurality of light-emitting elements 21, 22, 23 with at least a portion of the black curable resin layer 10 and the transparent curable resin layer 11 (hereinafter referred to as the filling step); and curing the filled black curable resin layer 10 and the transparent curable resin layer 11 (hereinafter referred to as the curing step). Hereinafter, a method for manufacturing a light-emitting electronic component according to an embodiment (also simply referred to as the "manufacturing method according to an embodiment") will be described with reference to FIGS. 2 to 4.

[0113] (i) Placement process In the manufacturing method of this embodiment, first, as shown in Fig. 2, the protective sheet 13 is peeled off from the integrated encapsulating sheet 1 to expose the black curable resin layer 10. Thereafter, the black curable resin layer 10 is brought into contact with the surface of the element-mounted substrate 2 on which the light emitting elements 21, 22, and 23 are arranged, and pressure bonding of the integrated encapsulating sheet 1 is started.

[0114] Before compression bonding, the thickness of the black curable resin layer 10 is preferably 10 to 95% of the height of the light emitting elements 21, 22, 23. The lower limit is more preferably 15% or more, and even more preferably 30% or more. The upper limit is more preferably 85% or less, and even more preferably 75% or less.

[0115] When the thickness of the black curable resin layer 10 is 10% or more of the height of the light-emitting elements 21, 22, and 23, the black curable resin layer 10 has sufficient light-shielding function between the light-emitting elements 21, 22, and 23. Furthermore, when the black curable resin layer 10 has a relatively low storage modulus and high fluidity, the resin can be sufficiently filled between the light-emitting elements 21, 22, and 23. When the thickness of the black curable resin layer 10 is 15% or more of the height of the light-emitting elements 21, 22, and 23, crack-like defects are less likely to occur on the surface even when the fluidity of the transparent curable resin layer 11 is relatively low. When the thickness of the black curable resin layer 10 is 30% or more of the height of the light-emitting elements 21, 22, and 23, the black curable resin layer 10, which has a light-shielding function, can be appropriately filled between the light-emitting elements 21, 22, and 23.

[0116] If the thickness of the black curable resin layer 10 is 95% or less of the height of the light emitting elements 21, 22, and 23, leakage of the black curable resin layer 10 to the outside during thermocompression bonding can be prevented, and light from the light emitting elements 21, 22, and 23 is less likely to be hindered from reaching the viewer. If the thickness of the black curable resin layer 10 is 85% or less of the height of the light emitting elements 21, 22, and 23, fluctuations in the film thickness of the black curable resin layer 10 that flows after pressing are less likely to occur, and variations in black shading are less likely to occur. If the thickness of the black curable resin layer 10 is 75% or less of the height of the light emitting elements 21, 22, and 23, the black curable resin layer 10, which has a light-blocking function, can be appropriately filled between the light emitting elements 21, 22, and 23.

[0117] The thickness of the transparent curable resin layer 11 before compression bonding is preferably 10 to 500% of the height of the light emitting elements 21, 22, 23. The lower limit is more preferably 20% or more, and even more preferably 30% or more. The upper limit is more preferably 200% or less, and even more preferably 150% or less.

[0118] When the thickness of the transparent curable resin layer 11 is 10% or more of the height of the light-emitting elements 21, 22, and 23, the transparent curable resin layer 11 easily functions as a sealing layer covering the light-emitting elements 21, 22, and 23. Furthermore, when the storage modulus of the transparent curable resin layer 11 is relatively high and the fluidity of the transparent curable resin layer 11 is suppressed, the transparent curable resin layer 11 can be prevented from flowing together with the black curable resin layer 10 during thermal curing, making it less likely for poor appearance to occur on the surface. When the thickness of the transparent curable resin layer 11 is 20% or more of the height of the light-emitting elements 21, 22, and 23, the range in which the transparent curable resin layer 11 can flow is sufficient, making it less likely for crack-like defects to occur on the surface. When the thickness of the transparent curable resin layer 11 is 30% or more of the height of the light-emitting elements 21, 22, and 23, the transparent curable resin layer 11 easily functions as a sealing layer covering the light-emitting elements 21, 22, and 23. Furthermore, when the storage modulus of the transparent curable resin layer 11 is relatively high and the fluidity of the layer 11 is suppressed, the transparent curable resin layer 11 can sufficiently press into the black curable resin layer 10.

[0119] The total thickness of the black curable resin layer 10 and the transparent curable resin layer 11 before compression bonding is preferably 110 to 550% of the height of the light emitting elements 21, 22, and 23. When the total thickness is equal to or greater than the above-mentioned lower limit value with respect to the height of the light emitting elements 21, 22, and 23, a part of the integrated encapsulating sheet 1 can be sufficiently embedded between the light emitting elements 21, 22, and 23. When the total thickness is equal to or less than the above-mentioned upper limit value with respect to the height of the light emitting elements 21, 22, and 23, thickness unevenness is unlikely to occur during compression bonding, and poor appearance is unlikely to occur on the surface.

[0120] The ratio of the thickness of the black curable resin layer 10 before compression bonding to the total thickness of the transparent curable resin layer 11 and the black curable resin layer 10 before compression bonding is preferably 10 to 90%, more preferably 15 to 70%. If this thickness ratio is equal to or greater than the above-mentioned lower limit, the degree of blackness can be increased and the contrast of the display can be sufficiently improved. If this thickness ratio is equal to or less than the above-mentioned upper limit, the black curable resin layer 10 is less likely to remain on the light-emitting elements 21, 22, and 23 during compression bonding, and brightness can be sufficiently improved.

[0121] (ii) Filling process Next, pressure bonding is continued to embed at least a part of the black curable resin layer 10 and the transparent curable resin layer 11 of the integrated encapsulating sheet 1 between the light emitting elements 21, 22, and 23 as shown in FIG. 3. At this time, the black curable resin layer 10 and the transparent curable resin layer 11 are filled between the plurality of light emitting elements 21, 22, and 23. At this time, if the storage modulus of the black curable resin layer 10 is relatively low and the fluidity of the layer 10 is ensured, the black curable resin layer 10 will easily follow the unevenness of the light emitting elements 21, 22, and 23 and fill between the light emitting elements 21, 22, and 23.

[0122] The temperature in the thermocompression bonding is preferably 80 to 120°C, more preferably 90 to 110°C. By setting the temperature to 80°C or higher, the fluidity of the black curing resin layer 10 of the integrated encapsulating sheet 1 is easily ensured. Furthermore, by setting the temperature to 120°C or lower, the light emitting elements 21, 22, and 23 are less likely to be damaged. By setting the temperature to 90 to 110°C, the fluidity of the black curing resin layer 10 can be controlled more precisely, and the occurrence of unevenness and crack-like defects can be suppressed.

[0123] The pressure in the thermocompression bonding is 0.05 to 5.0 MPa, preferably 0.05 to 1.0 MPa, and more preferably 0.1 to 0.5 MPa. By setting the pressure to a preferred lower limit or higher, the black curable resin layer 10 can be sufficiently filled between the light emitting elements 21, 22, and 23. By setting the pressure to a preferred upper limit or lower, damage to the light emitting elements 21, 22, and 23 is reduced. The thermocompression bonding is preferably performed using a vacuum press capable of molding in a vacuum state. This makes it easier to avoid defects caused by air being mixed into the resulting light-emitting electronic component 5.

[0124] (iii) Curing process After the pressure-bonding, as shown in FIG. 4, the protective sheet 14 is peeled off and then thermally cured, so that the black curable resin layer 10 and the transparent curable resin layer 11 of the integrated encapsulating sheet 1 become a black resin layer 30 (a cured layer of the black curable resin layer 10) and a transparent resin layer 31 (a cured layer of the transparent curable resin layer 11), thereby obtaining a light-emitting electronic component 5.

[0125] The curing temperature is preferably 100 to 160°C, and more preferably 110 to 150°C. By setting the curing temperature to 100°C or higher, the black curable resin layer 10 and the transparent curable resin layer 11 of the integrated encapsulating sheet 1 can be reliably cured. By setting the curing temperature to 110°C or higher, the curing time of the black curable resin layer 10 and the transparent curable resin layer 11 can be shortened. Furthermore, by setting the curing temperature to the above upper limit temperature or lower, the light emitting elements 21, 22, and 23 are less likely to be damaged.

[0126] The curing time varies depending on the curing temperature, but is preferably 30 to 360 minutes, more preferably 45 to 180 minutes. If the storage modulus of the transparent curable resin layer 11 is relatively high and the fluidity of the layer 11 is suppressed at the curing temperature, poor appearance of the black curable resin layer 10 and the transparent curable resin layer 11 after curing can be suppressed.

[0127] 2 to 4 , a light-emitting electronic component 5 is obtained in which the integrated encapsulating cured sheet 3 is pressure-bonded to the surface of the element-mounted substrate 2 on which the light-emitting elements 21, 22, and 23 are arranged, the surface being the light-emitting elements 21, 22, and 23. In the obtained light-emitting electronic component 5, the black curable resin layer 10 and the transparent curable resin layer 11 are cured to form the black resin layer 30 and the transparent resin layer 31. At least a portion of the black resin layer 30 and the transparent resin layer 31 are filled between the light-emitting elements 21, 22, and 23.

[0128] (Second embodiment) Next, a second embodiment will be described. Portions common to the first embodiment will be assigned the same reference numerals and description thereof will be omitted. Fig. 5 shows a cross-sectional view of an integrated encapsulating sheet according to another embodiment, taken in the same manner as Fig. 1. Fig. 6 shows a cross-sectional view of a light-emitting electronic component according to another embodiment manufactured using the integrated encapsulating sheet of Fig. 5, taken in the same manner as Fig. 1.

[0129] 1. Integrated encapsulating sheet The integrated encapsulating sheet 1a according to another embodiment further includes a hard coat layer 15 on the surface of the substrate layer 12 opposite to the surface in contact with the transparent curable resin layer 11. Hereinafter, the hard coat layer will be described.

[0130] (5) Hard Coat Layer The hard coat layer 15 is formed on the surface of the base layer 12 opposite to the surface on which the transparent curable resin layer 11 is formed. The hard coat layer 15 has a scratch-proof effect on the base layer 12 and is a layer for protecting the light-emitting electronic component 5 from scratches. The hard coat layer 15 is a cured layer.

[0131] [hardness] The pencil hardness of the surface of the hard coat layer 15 is preferably H or higher, more preferably 2H or higher, and even more preferably 3H or higher.

[0132] [Surface roughness] The arithmetic mean roughness (Ra) of the surface of the hard coat layer 15 is preferably 0.1 to 1 μm, more preferably 0.2 to 1 μm, and even more preferably 0.3 to 1 μm. When the Ra of the hard coat layer 15 is equal to or greater than the preferred lower limit, the reflectance of the surface of the hard coat layer 15 can be reduced. When the Ra of the hard coat layer 15 is equal to or less than the preferred upper limit, production can be facilitated.

[0133] [Total light transmittance] The hard coat layer 15 is preferably prepared so that the total light transmittance is 30 to 99%, more preferably 50 to 99%, and even more preferably 60 to 99%. When the total light transmittance of the hard coat layer 15 is equal to or greater than the lower limit, light reaching the viewer side is not hindered.

[0134] [resin] The hard coat layer 15 may be composed of either a thermoplastic resin or a thermosetting resin, and is preferably composed of a thermosetting resin. Examples of the thermosetting resin that constitutes the hard coat layer 15 include acrylic resin, polyurethane resin, silicone resin, melamine resin, etc., and the hard coat layer 15 may contain one or more of these. The hard coat layer 15 may also contain a black pigment or black dye.

[0135] [Fine particles] The hard coat layer 15 preferably contains fine particles. As the fine particles, inorganic fine particles, organic fine particles, or both can be used. Examples of inorganic fine particles include silica fine particles and titanium fine particles. Examples of organic fine particles include polymethyl methacrylate resin (PMMA resin) and polyurethane resin. Among these, silica fine particles are preferred. By containing fine particles, the surface roughness of the hard coat layer 15 can be adjusted and the surface hardness can be improved.

[0136] [Film thickness] The thickness of the hard coat layer 15 is preferably 1 to 20 μm, more preferably 2 to 10 μm, and even more preferably 3 to 8 μm. When the thickness of the hard coat layer 15 is equal to or greater than the preferred lower limit, sufficient hardness can be ensured. When the thickness of the hard coat layer 15 is equal to or less than the preferred upper limit, problems such as curling do not occur.

[0137] 2. Manufacturing method of integrated encapsulating sheet To obtain the integrated encapsulating sheet 1a according to the present embodiment, for example, a protective sheet 13 obtained in the same manner as in the first embodiment is coated with a coating liquid of a curable resin composition for the black curable resin layer 10 and dried, and a substrate layer 12 on which a hard coat layer 15 has been formed in advance is coated with a coating liquid of a curable resin composition for the transparent curable resin layer 11 on the surface opposite to the hard coat layer 15 and dried. The lamination method and the like thereafter are the same as in the first embodiment described above.

[0138] The hard coat layer 15 formed on the substrate layer 12 can be obtained by applying a coating agent for the hard coat layer 15 to the surface of the substrate layer 12 and curing the coating agent. Examples of methods for applying the coating agent include various coaters such as a die coater, gravure coater, roll coater, curtain flow coater, spin coater, bar coater, reverse coater, kiss coater, fountain coater, rod coater, air doctor coater, knife coater, blade coater, cast coater, and screen coater. Examples of methods for curing the coating agent include heat curing, ultraviolet curing, and electron beam curing.

[0139] As a result of lamination, a laminate is obtained in which the black curable resin layer 10, the transparent curable resin layer 11, the substrate layer 12, and the hard coat layer 15 are laminated in this order on the protective sheet 13. A protective sheet 14 may be laminated on the outer surface of the hard coat layer 15 as needed.

[0140] 3. Substrate with elements The element-mounted substrate 2 is the same as that in the first embodiment described above.

[0141] 4. Light-emitting electronic components and manufacturing methods thereof A light-emitting electronic component 5a according to this embodiment includes a device-mounted substrate 2 having a plurality of light-emitting elements 21, 22, and 23 arranged on a substrate 20, and an integrated encapsulating cured sheet 3a that is pressure-bonded to the surface of the device-mounted substrate 2 on which the plurality of light-emitting elements 21, 22, and 23 are arranged. The integrated encapsulating cured sheet 3a is made up of, from the side in contact with the device-mounted substrate 2, a black resin layer 30 that shields the spaces between the plurality of light-emitting elements 21, 22, and 23 and has a total light transmittance of 1 to 10%, a transparent resin layer 31 that is more light transparent than the black resin layer 30, a base layer 12 that supports the black resin layer 30 and the transparent resin layer 31, and a hard coat layer 15, laminated in this order.

[0142] The method for manufacturing the light-emitting electronic component 5a according to this embodiment is the same as that of the first embodiment described above. [Example]

[0143] The present invention will be specifically described below with reference to examples, although the present invention is not limited to these examples.

[0144] <Raw materials> Details of the raw materials used in each example and comparative example are as follows.

[0145] [Epoxy resin for curable resin layer] HP-7200H: DIC Corporation, cyclopentadiene novolac multifunctional epoxy resin (solid), softening point 82°C, epoxy equivalent 227g / eq. jER (registered trademark) YX7200B35: manufactured by Mitsubishi Chemical Corporation, phenoxy resin (MEK solution, solid content 35% by mass), glass transition temperature 150°C, epoxy equivalent 8781 g / eq., weight average molecular weight 30,000. EOCN 1020-55: Manufactured by Nippon Kayaku Co., Ltd., o-cresol novolac epoxy resin, solid, softening point 55°C, epoxy equivalent 194g / eq.

[0146] [Elastomer] NX775: Zeon Corporation, carboxy-modified nitrile rubber, weight average molecular weight 208,000.

[0147] [Curing catalyst] 2PZ-CN: 1-cyanoethyl-2-phenylimidazole, manufactured by Shikoku Chemicals Co., Ltd.

[0148] [Carbon black] Special Black #4: Gas black, manufactured by ORION ENGINEERED CARBONS.

[0149] [solvent] MEK: Methyl ethyl ketone, manufactured by Junsei Chemical Co., Ltd. PGM: Propylene glycol monomethyl ether, manufactured by Junsei Chemical Co., Ltd.

[0150] [Resin and fine particles for hard coat layer] 8KX-078: Manufactured by Taisei Fine Chemical Co., Ltd., solids concentration 40% by mass, UV-curable acrylic polymer, weight-average molecular weight 40,000. Chemisnow (registered trademark) MX-500L: manufactured by Soken Chemical & Engineering Co., Ltd., cross-linked acrylic monodisperse particles, average particle diameter 5 μm.

[0151] [Photopolymerization initiator] Omnirad TPO H: Photoradical polymerization initiator manufactured by IGM Resins BV.

[0152] [PET film for base layer] Cosmoshine (registered trademark) A4300: Manufactured by Toyobo Co., Ltd., PET film, thickness 75 μm.

[0153] [Protection sheet] 1-E: Release film manufactured by Nippa, thickness 50 μm.

[0154] [Preparation of coating liquid for curable resin layer] Coating liquids for the black curable resin layer and the transparent curable resin layer were prepared with the compositions shown below. Specifically, the compositions shown below were mixed with a solvent of MEK / PGM = 80 / 20 (volume ratio) to prepare a coating liquid for the black curable resin layer with a solid content concentration of 35 mass % and a coating liquid for the transparent curable resin layer with a solid content concentration of 40 mass %. The content of carbon black in the coating liquid for the black curable resin layer will be described later. The compositions shown are in parts by mass of the solid content of each material.

[0155] [Coating liquid for black curable resin layer] ·HP7200H (70 parts by mass) ·NX775 (30 parts by mass) ·2PZ-CN (3 parts by mass) Special Black #4 (shown as "carbon black content" in Table 1 below)

[0156] [Coating liquid for transparent curable resin layer] ·EOCN 1020-55 (50 parts by mass) ·YX7200B35 (30 parts by mass) ·NX775 (20 parts by mass) ·2PZ-CN (3 parts by mass)

[0157] [Preparation of Coating Agent for Hard Coat Layer] A coating agent for a hard coat layer was prepared according to the following composition: Specifically, the composition described below was mixed with an MEK solvent to prepare a coating agent for a hard coat layer with a solid content concentration of 30 mass %. [Coating agent for hard coat layer] ·8KX-078 (100 parts by mass) ·MX-500L (15 parts by mass) ·Omnirad TPO H (2 parts by mass)

[0158] [Preparation of film for base layer] One side of a 75 μm thick PET film was subjected to corona treatment, and a coating agent for a hard coat layer was applied using a bar coater so that the dry film thickness was 5 μm. After drying at 100° C. for 5 minutes, ultraviolet rays with a wavelength of 365 nm were applied at 400 mJ / cm. 2 The coating agent was cured by irradiation to form a hard coating layer, thereby obtaining a film for a base layer having a thickness of 80 μm.

[0159] Example 1 [Preparation of Transparent Curable Resin Layer] The transparent curable resin layer coating solution was applied to the surface of the substrate layer film opposite the surface on which the hard coat layer was formed using a film applicator with a film thickness adjustment function (manufactured by Allgood Co., Ltd.) so that the dry film thickness would be 30 μm. The coating was dried at 100° C. for 5 minutes to obtain a transparent layer laminated sheet in which the hard coat layer, substrate layer, and transparent curable resin layer were laminated in this order.

[0160] [Preparation of black curable resin layer] The coating liquid for the black curable resin layer was applied to the release surface of release PET 1-E (Nippa, 50 μm) using a film applicator with film thickness adjustment function (Allgood Co., Ltd.) so that the dry film thickness would be 50 μm. Drying was performed at 100°C for 5 minutes to obtain a black layer laminate sheet in which the black curable resin layer was supported by the release PET. The carbon black contained in the coating liquid for the black curable resin layer was 0.31 parts by mass.

[0161] [Production of integrated encapsulating sheet] The obtained transparent layer laminated sheet and black layer laminated sheet were stacked so that the transparent curable resin layer and the black curable resin layer were in contact with each other, and laminated with a roll laminator at 60°C to obtain an integrated encapsulating sheet of Example 1.

[0162] [Substrate with evaluation element] A substrate with LED elements for evaluation was prepared by arranging multiple LED elements, each 0.1 x 0.2 mm in size and 65 μm in height, on an epoxy glass substrate. This substrate with LED elements for evaluation was used to measure the brightness before mounting in terms of the luminance transmittance, which will be described later.

[0163] [Manufacturing of light-emitting electronic components] The release PET from each integrated encapsulant sheet was peeled off, and the black curable resin layer was placed in contact with the LED light-emitting element of the evaluation element-mounted substrate. The black curable resin layer and the transparent curable resin layer were then filled between the light-emitting elements in a vacuum press under conditions of 100 hPa, 100°C, 0.36 MPa, and 3 minutes. After filling, the black curable resin layer and the transparent curable resin layer were heated in an oven at 120°C for 1 hour to thermally cure the black curable resin layer and the transparent curable resin layer, resulting in a light-emitting electronic component. The light-emitting electronic component was then subjected to the evaluation of concealment and measurement of post-mounting brightness in terms of luminance transmittance, as described below.

[0164] <Example 2> The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 0.46 parts by mass.

[0165] Example 3 The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 0.60 parts by mass.

[0166] Example 4 The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 0.71 parts by mass.

[0167] <Example 5> The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 0.94 parts by mass.

[0168] <Comparative Example 1> The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 0.23 parts by mass.

[0169] <Comparative Example 2> The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 1.43 parts by mass.

[0170] <Comparative Example 3> The same procedure as in Example 1 was carried out except that the amount of carbon black contained in the coating liquid for the black curable resin layer was changed to 4.00 parts by mass.

[0171] <Evaluation method> [Measurement of storage modulus of each curable resin layer at 100°C] The storage modulus at 100°C of the black curable resin layer and transparent curable resin layer (hereinafter also referred to as each curable resin layer) according to each Example and Comparative Example was measured using a viscoelasticity measuring device (RSA-G2 manufactured by TA Instruments) under conditions of a measurement frequency of 1 Hz and a temperature rise rate of 5°C / min in accordance with JIS K7244. Specifically, each layer was coated on release PET 1-E (Nippa Corporation, release film, thickness 50 μm) so that the transparent curable resin layer had a dry film thickness of 30 μm and the black curable resin layer had a dry film thickness of 50 μm, and each curable resin layer was peeled off from 1-E and measured according to the above conditions. As a result, the storage modulus at 100°C of the transparent curable resin layer was 5.72 × 105 The storage modulus at 100° C. of the black curable resin layer in each example and comparative example is shown in Table 1 below.

[0172] [Measurement of total light transmittance] The black layer laminated sheets obtained as described in each Example and Comparative Example were heated in an oven at 120°C for 1 hour to thermally cure the black curable resin layer, resulting in black test sheets in which the black resin layer was supported by release PET 1-E. The total light transmittance of each test black sheet was measured using a haze meter (NDH5000, manufactured by Nippon Denshoku Industries Co., Ltd.) according to JIS K 7361-1. Similarly, the total light transmittance of release PET 1-E alone was also measured. The values calculated from the measured values of each test black sheet, excluding the effect of release PET 1-E, are shown in Table 1 below.

[0173] [L* value measurement] For the integrated encapsulating sheets according to the above-mentioned Examples and Comparative Examples, the L* value was measured from the hard coat layer side using a Konica Minolta CR-5 colorimeter in accordance with JIS Z 8781-4, a light source of D65, a field of view of 2°, a reflection method, and an SCE method. Furthermore, for the above-mentioned black layer laminated sheet, the L* value was measured from the release PET 1-E side under the same conditions. The measured L* values are shown in Table 1.

[0174] [Calculation of luminance transmittance and luminance variation coefficient] The luminance of the light-emitting element on the evaluation element-mounted substrate before the integrated encapsulating sheet was crimped and filled was defined as the pre-mounting luminance, and the luminance of the light-emitting element of the light-emitting electronic component was defined as the post-mounting luminance. For the measurement, nine locations were randomly selected from the light-emitting elements on the evaluation element-mounted substrate. The pre-mounting luminance and post-mounting luminance of the nine selected locations were measured using a Konica Minolta CA-410 luminance meter. The luminance transmittance was calculated using the following formula (I). The average value of the calculated luminance transmittance at the nine locations is shown in Table 1 below. An average luminance transmittance of 65% or more was deemed acceptable, and an average luminance transmittance of less than 65% was deemed unacceptable. Furthermore, the coefficient of variation of luminance for each Example and Comparative Example was calculated using the following formula (II) from the average and standard deviation of the measured post-mounting luminance at the nine locations. A coefficient of variation of luminance of less than 20% was deemed acceptable, and an average luminance of 20% or more was deemed unacceptable. Luminance transmittance (%) = (luminance after mounting / luminance before mounting) × 100 (I) Coefficient of variation of brightness (%) = (standard deviation of brightness after mounting / average brightness after mounting) x 100 (II)

[0175] [Evaluation of hiding power] For the obtained light-emitting electronic components, the light-emitting elements on the substrate were observed from the hard coat layer side of the integrated encapsulating cured sheet using a digital microscope VHX-7000 (manufactured by KEYENCE Corporation), and the concealment ability of the light-emitting elements was evaluated. When solder oozing out from the light-emitting element onto the substrate was not visible, the result was evaluated as pass (◯), and when solder was visible, the result was evaluated as fail (×). The evaluation results are shown in Table 1 below.

[0176] Table 1 shows the results of each evaluation test.

[0177] [Table 1]

[0178] The integrated encapsulating sheets according to each Example passed both the hiding power and the luminance transmittance, and also had a low coefficient of variation in luminance. These sheets were able to ensure blackness while suppressing luminance loss and luminance unevenness, and also had little variation in luminance transmittance depending on the location. On the other hand, the integrated encapsulating sheet according to Comparative Example 1 failed the hiding power. The integrated encapsulating sheets according to Comparative Examples 2 and 3 were able to fail the luminance transmittance and had a high coefficient of variation in luminance. From the above results, only the integrated encapsulating sheets in which the total light transmittance in the black resin layer (in the cured state of the black curable resin layer) is 1 to 20% were able to ensure blackness while suppressing luminance loss and luminance unevenness. [Industrial Applicability]

[0179] The integrated encapsulating sheet according to the present invention can be used, for example, as a sheet for sealing a substrate on which a plurality of light-emitting elements are arranged. [Explanation of symbols]

[0180] DESCRIPTION OF SYMBOLS 1,1a... Integrated encapsulating sheet, 2... Substrate with element, 3,3a... Integrated encapsulating cured sheet, 5,5a... Light-emitting electronic component, 10... Black curable resin layer, 11... Transparent curable resin layer, 12... Base material layer, 13,14... Protective sheet, 15... Hard coat layer, 20... Substrate, 21,22,23... Light-emitting element, 30... Black resin layer, 31... Transparent resin layer

Claims

1. An integrated encapsulating sheet to be pressure-bonded to a surface of an element-mounted substrate on which a plurality of light-emitting elements are arranged, the surface comprising: a black cured resin layer that shields light between the plurality of light-emitting elements, a transparent cured resin layer that has higher light transmittance than the black cured resin layer, and a base layer that supports the black cured resin layer and the transparent cured resin layer, stacked in this order; The black curable resin layer in a cured state has a total light transmittance of 1 to 20%.

2. The integrated encapsulating sheet according to claim 1, wherein the black curable resin layer has a total light transmittance of 1 to 10% in a cured state.

3. The integrated encapsulating sheet according to claim 1, wherein the black curable resin layer in a cured state has a total light transmittance of 2.35% or more and less than 5%.

4. 2. The integrated encapsulating sheet according to claim 1, wherein the transparent curable resin layer has a total light transmittance of 70 to 99% in a cured state.

5. The integrated encapsulating sheet according to claim 1 , wherein a storage modulus at 100° C. of the transparent curable resin layer is greater than a storage modulus at 100° C. of the black curable resin layer.

6. The storage modulus of the transparent curable resin layer at 100°C is 1.0 × 10 ７ The integrated sealing sheet according to claim 1, wherein the elastic modulus is 0.05 Pa or less.

7. The storage modulus of the black curable resin layer at 100°C is 1.0 × 10 ５ The integrated sealing sheet according to claim 1, wherein the elastic modulus is 0.05 Pa or less.

8. 2. The integrated encapsulating sheet according to claim 1, wherein the black curable resin layer and the transparent curable resin layer contain a curable resin composition, and the curable resin composition contains an epoxy resin.

9. The integrated encapsulating sheet according to claim 1 , wherein the transparent curable resin layer contains an epoxy resin having a weight average molecular weight of 10,000 or more.

10. The integrated encapsulating sheet according to claim 1 , wherein the black curable resin layer comprises an elastomer.

11. The integrated encapsulating sheet according to claim 1 , wherein the substrate layer further comprises a hard coat layer on a surface opposite to a surface in contact with the transparent curable resin layer.

12. an element-mounted substrate having a plurality of light-emitting elements arranged on the substrate; an integrated encapsulating cured sheet that is pressure-bonded to a surface of the element-mounted substrate on which the plurality of light-emitting elements are arranged, the integrated encapsulating cured sheet is made up of a black resin layer that shields light between the plurality of light-emitting elements, a transparent resin layer that has higher light transmittance than the black resin layer, and a base layer that supports the black resin layer and the transparent resin layer, laminated in this order from the side that contacts the element-mounted substrate; The light-emitting electronic component has a total light transmittance of 1 to 20% for the black resin layer.

13. the thickness of the transparent resin layer is 0.1 to 5.0 times the height of the plurality of light-emitting elements; 13. The light-emitting electronic component according to claim 12, wherein the thickness of the black resin layer is 0.1 to 0.9 times the height of the plurality of light-emitting elements.

14. A step of arranging the integrated encapsulating sheet according to any one of claims 1 to 11 on a surface of an element-mounted substrate on which a plurality of light-emitting elements are arranged; filling the black cured resin layer and at least a portion of the transparent cured resin layer between the plurality of light-emitting elements; and curing the black curable resin layer and the transparent curable resin layer.

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