Sheet for sealing optical semiconductor element, and optical semiconductor device

Abstract

The invention relates to a sheet for sealing an optical semiconductor element and an optical semiconductor device. Provided is a sheet for sealing an optical semiconductor element, which has excellent antireflection properties, sealing properties for optical semiconductor elements, and workability during splicing, and which is not susceptible to sheet defects when adjacent optical semiconductor devices are pulled apart from each other. A sheet (1) for sealing an optical semiconductor element is a sheet for sealing one or more optical semiconductor elements (6) disposed on a substrate (5). The optical semiconductor element sealing sheet (1) has a sealing resin layer (2) including at least a colored layer (22) and a thermosetting non-colored adhesive layer (21). The colored layer (22) contains a colorant. The elastic modulus G'of the non-colored adhesive layer (21) before curing at 130 DEG C is 0.5 kPa to 10 kPa, and the non-colored adhesive layer is in contact with the optical semiconductor element (6) when the optical semiconductor element (6) is sealed by the optical semiconductor element sealing sheet (1).

Description

Technical Field

[0001] The present invention relates to a sheet for sealing an opto-semiconductor element and an opto-semiconductor device. More specifically, the present invention relates to a sheet suitable for sealing an opto-semiconductor element, and an opto-semiconductor device having a structure in which the opto-semiconductor element is sealed with the sheet. Background Art

[0002] It is known that a self-luminous display device such as a small / micro LED display device (Mini / Micro Light Emitting Diode Display) has a structure in which a plurality of LEDs are arranged on a substrate and the plurality of LEDs are sealed with a sealing resin. As a method of uniformly sealing the plurality of LEDs with the above-mentioned sealing resin, the following method is known: a liquid resin is injected into an area where the plurality of LEDs are arranged to bury the plurality of LEDs, and then the liquid resin is cured by heat or ultraviolet irradiation.

[0003] However, in the method of sealing an opto-semiconductor element such as an LED with a liquid resin, there are problems such as poor operability, such as dripping of the liquid resin during coating and attachment of the liquid resin to an undesired area. On the other hand, it is easy to adjust to use a sealing sheet having a sealing layer for sealing an opto-semiconductor element instead of a liquid resin, and the opto-semiconductor element can be sealed in a simple process in a short time.

[0004] In addition, in an image display device having a self-luminous display device, wirings (metal wirings) of metals, metal oxides such as ITO, etc. are arranged on the substrate of the display panel. Such a display device has the following problems: for example, when turned off, light is reflected due to the above-mentioned metal wiring, etc., and the appearance of the screen is poor and the design is poor. Therefore, as a sealing material for an opto-semiconductor element, a technique using an antireflection layer for preventing reflection of metal wiring has been adopted.

[0005] Incidentally, with the high definition such as 4K and 8K, the demand for larger-screen image display devices is increasing. In addition, the use of large-screen image display devices for advertising displays, bulletin boards, etc. on signs in outdoor areas, public facilities, etc. is also being promoted. However, when manufacturing a large-screen image display device, there are problems of reduced yield and increased manufacturing cost. In order to manufacture a large-screen image display device at a lower cost, a tiled display in which a plurality of opto-semiconductor devices such as image display devices are arranged in a tiled manner has been studied.

[0006] In Patent Document 1, a tiled display device in which a plurality of display devices each having a light-emitting diode substrate with a sealing member are arranged side by side is disclosed. In the light-emitting diode substrate with the sealing member, a sealing member containing a thermoplastic resin seals the light-emitting diode.

[0007] Prior art documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 2021-9937 Summary of the invention

[0010] Problems to be solved by the invention

[0011] Here, the sealing property of the light semiconductor element of the above-mentioned sealing sheet is excellent. In order to sufficiently seal the light semiconductor element, it is important that the adhesion to the light semiconductor element and the substrate having the light semiconductor element is excellent. However, when the adhesive layer using a thermoplastic resin described in Patent Document 1 is used as a sealing member, there are the following problems: the adhesiveness is high, and when a plurality of light semiconductor devices are arranged in a tile shape, that is, when splicing, it is difficult for the light semiconductor device to separate from the hand or the jig, and the workability is poor.

[0012] In addition, when there is a positional deviation or the like between the light semiconductor devices arranged adjacent to each other during splicing and position correction is required. In order to perform position correction, it is necessary to temporarily separate the adjacent light semiconductor devices. However, when separating, the sealing sheet in one light semiconductor device adheres to the sealing sheet in the adjacent other light semiconductor device and pulls each other, and sometimes a defect occurs in the sealing sheet in one light semiconductor device. Such a defective condition is particularly likely to occur in a sealing sheet having excellent adhesion to a light semiconductor element and a substrate.

[0013] The present invention is proposed based on such a situation, and its object is to provide a light semiconductor element sealing sheet having excellent antireflection property, sealing property of a light semiconductor element, and workability during splicing, and being less likely to cause a defect in the sheet when separating adjacent light semiconductor devices from each other.

[0014] Means for solving the problem

[0015] The inventor of the present invention conducted in-depth research to achieve the above object, and as a result, found that according to a specific sealing sheet, the antireflection property, the sealing property of the light semiconductor element, and the workability during splicing are excellent, and a defect in the sheet is less likely to occur when separating adjacent light semiconductor devices from each other. The present invention has been completed based on these findings.

[0016] That is, the present invention provides a sheet for sealing an opto-semiconductor element, which is a sheet for sealing one or more opto-semiconductor elements arranged on a substrate. Among them, the sheet has a sealing resin layer, and the sealing resin layer at least includes a colored layer and a non-colored adhesive layer with thermosetting properties. The colored layer contains a colorant, and the elastic modulus G' of the non-colored adhesive layer before curing at 130 °C is 0.5 kPa to 10 kPa. The non-colored adhesive layer is the layer that contacts the opto-semiconductor element when sealing the opto-semiconductor element.

[0017] The thickness of the above-mentioned non-colored adhesive layer is preferably 5 μm to 75 μm.

[0018] The elastic modulus E' of the above-mentioned non-colored adhesive layer at room temperature before curing is preferably 500 MPa to 4000 MPa.

[0019] The elastic modulus E' of the above-mentioned non-colored adhesive layer at room temperature after curing is preferably 500 MPa to 4000 MPa.

[0020] The light transmittance of the above-mentioned non-colored adhesive layer at a wavelength of 600 nm after curing is preferably greater than 80%.

[0021] In the state where the above-mentioned sheet for sealing an opto-semiconductor element seals the opto-semiconductor element, the distance from the above-mentioned opto-semiconductor element to the above-mentioned non-colored adhesive layer is preferably 0 μm to 20 μm.

[0022] The above-mentioned colored layer is preferably a colored adhesive layer with thermosetting properties, and the light transmittance of the above-mentioned colored adhesive layer at a wavelength of 600 nm after curing is preferably 0% to 80%.

[0023] The above-mentioned colored layer is preferably a colored adhesive layer with thermosetting properties, and the ratio of the elastic modulus E' of the above-mentioned colored adhesive layer at room temperature after curing to the elastic modulus E' at room temperature before curing [elastic modulus E' at room temperature after curing / elastic modulus E' at room temperature before curing] is preferably 0.6 to 2.0.

[0024] The above-mentioned sheet for sealing an opto-semiconductor element may have a layer with antiglare property and / or antireflection property on the surface on the side opposite to the side in contact with the opto-semiconductor element with respect to the above-mentioned sealing resin layer.

[0025] In addition, the present invention provides an opto-semiconductor device, which has: a substrate; an opto-semiconductor element arranged on the above-mentioned substrate; and the above-mentioned sheet for sealing an opto-semiconductor element or its cured product for sealing the above-mentioned opto-semiconductor element.

[0026] Advantages of the Invention

[0027] The sheet for sealing an opto-semiconductor element according to the present invention has excellent antireflectivity, sealing property of the opto-semiconductor element, and workability during splicing, and is less likely to cause defects in the sheet when adjacent opto-semiconductor devices are pulled apart from each other. Therefore, after splicing of the opto-semiconductor devices, when there is a positional shift or the like between adjacent opto-semiconductor devices or when rearrangement is required, position correction can be easily performed without any problems, loss of opto-semiconductor devices can be reduced, and a display with good appearance can be economically manufactured. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 FIG. is a cross-sectional view of a sheet for sealing an opto-semiconductor element according to an embodiment of the present invention.

[0029] Figure 2 FIG. shows a partial cross-sectional view of an embodiment of an opto-semiconductor device using the Figure 1 sheet for sealing an opto-semiconductor element shown.

[0030] Figure 3 FIG. shows a partial cross-sectional view of another embodiment of an opto-semiconductor device using the Figure 1 sheet for sealing an opto-semiconductor element shown.

[0031] Figure 4 FIG. shows an external view of an embodiment of an opto-semiconductor device fabricated by splicing the Figure 2 opto-semiconductor devices shown.

[0032] REFERENCE SIGNS LIST

[0033] 1 Sheet for sealing an opto-semiconductor element

[0034] 2 Sealing resin layer

[0035] 21 Non-colored adhesive layer

[0036] 22 Colored layer

[0037] 3 Release liner

[0038] 4 Substrate portion

[0039] 41 Substrate film

[0040] 42 Functional layer

[0041] 5 Substrate

[0042] 6 Opto-semiconductor element

[0043] 7 Cured sealing layer

[0044] 71 Non-colored adhesive layer

[0045] 72 Colored layer

[0046] 10, 20 Optical Semiconductor Devices Detailed Embodiments

[0047] [Sheet for Sealing Optical Semiconductor Element]

[0048] The sheet for sealing an optical semiconductor element of the present invention has at least a sealing resin layer including a colored layer and a non-colored adhesive layer. It should be noted that in this specification, the sheet for sealing an optical semiconductor element refers to a sheet for sealing one or more optical semiconductor elements disposed on a substrate using the sealing resin layer. Further, in this specification, "sealing an optical semiconductor element" means burying at least a part of the optical semiconductor element in the sealing resin layer, or following and covering at least a part of the optical semiconductor element with the above-mentioned sealing resin layer. The above-mentioned sealing resin layer has flexibility such that at least a part of the optical semiconductor element can be buried therein, or at least a part of the optical semiconductor element can be followed and covered with the above-mentioned sealing resin layer.

[0049] [Sealing Resin Layer]

[0050] The above-mentioned sealing resin layer includes at least the above-mentioned colored layer and the above-mentioned non-colored adhesive layer. The above-mentioned sealing resin layer may include other layers in addition to the above-mentioned colored layer and the above-mentioned non-colored adhesive layer. As the above-mentioned other layers, a non-colored adhesive layer or the like can be cited. Each layer (colored layer and non-colored adhesive layer) constituting the above-mentioned sealing resin layer can be a single layer in the above-mentioned sealing resin layer, or can be multiple layers having the same or different compositions. In the case of including multiple colored layers or non-colored adhesive layers, the above-mentioned multiple layers can be laminated in contact with each other, or can be laminated in isolation (for example, two non-colored adhesive layers are laminated with a colored layer therebetween).

[0051] In the above-mentioned sealing resin layer, the layer that contacts the optical semiconductor element when sealing the optical semiconductor element (that is, the layer closest to the optical semiconductor element side in the above-mentioned sealing resin layer) is a non-colored adhesive layer having thermosetting properties. When the layer that contacts the optical semiconductor element is a non-colored adhesive layer having thermosetting properties, the workability is excellent before thermosetting, and further, adhesiveness to the optical semiconductor element and the substrate is exhibited by thermosetting. Further, the above-mentioned colored layer is preferably a colored adhesive layer (thermosetting adhesive layer) having thermosetting properties. It is preferable that all the colored layers and non-colored layers in the above-mentioned sealing resin layer are thermosetting adhesive layers. In this specification, an "adhesive layer" is different from a pressure-sensitive adhesive layer, and has no or extremely little adhesiveness or tackiness on the surface, and has curability, and adheres to an adherend through curing.

[0052] (Non-colored Adhesive Layer)

[0053] The above non-coloring adhesive layer is a layer different from the above coloring layer and is not a layer aimed at preventing light reflection caused by metal wirings or the like. The above non-coloring adhesive layer may be a colorless layer or may be slightly colored. In addition, the above non-coloring adhesive layer may be, for example, a diffusion function layer aimed at exerting the function of diffusing light or a non-diffusion function layer not aimed at exerting the function of diffusing light. The above non-coloring adhesive layer may be transparent or opaque. The above non-coloring adhesive layer is preferably a resin layer composed of resin.

[0054] The above non-coloring adhesive layer is a layer located at the position in contact with the optical semiconductor element when sealing the optical semiconductor element with the above-mentioned sheet for sealing an optical semiconductor element. It should be noted that in the case where the above-mentioned sealing resin layer includes multiple non-coloring layers, at least one non-coloring adhesive layer having thermosetting properties may be located at the position in contact with the optical semiconductor element. The non-coloring adhesive layer in contact with the optical semiconductor element may be the above-mentioned diffusion function layer or the above-mentioned non-diffusion function layer.

[0055] Relative to the total amount (100% by mass) of the non-coloring adhesive layer, the content ratio of the coloring agent in the above non-coloring adhesive layer is preferably less than 0.2% by mass, more preferably less than 0.1% by mass, further preferably less than 0.05% by mass, and may be less than 0.01% by mass or less than 0.005% by mass.

[0056] There is no particular limitation on the total light transmittance of the above non-coloring adhesive layer. From the viewpoint of ensuring brightness, it is preferably 40% or more, more preferably 60% or more, further preferably 70% or more, and particularly preferably 80% or more. In addition, there is no particular limitation on the upper limit value of the total light transmittance of the above non-coloring adhesive layer, and it may be less than 100%, or may be 99.9% or less or 99% or less.

[0057] The total light transmittance of the above non-coloring adhesive layer is the value of a single layer, can be measured by the methods specified in JIS K7136 and JIS K7361-1, and can be controlled by the type, thickness, etc. of the non-coloring adhesive layer.

[0058] The above diffusion function layer is a layer aimed at diffusing light. When the above-mentioned sealing resin layer has the above diffusion function layer, the light emitted from the optical semiconductor element diffuses in the diffusion function layer. For example, the light emitted from the side of the optical semiconductor element is emitted toward the front direction of the image display device, and the front brightness of the image display device is improved. The above diffusion function layer is preferably a resin layer composed of resin. There is no limitation on the above diffusion function layer, and it preferably contains light-diffusing fine particles. That is, the above diffusion function layer preferably contains light-diffusing fine particles dispersed in the resin layer. The above light-diffusing fine particles may use only one kind or may use two or more kinds.

[0059] The above-mentioned light-diffusing particles have an appropriate refractive index difference from the resin constituting the diffusion functional layer, and impart diffusion performance to the diffusion functional layer. Examples of the light-diffusing particles include inorganic particles and polymer particles. Examples of the material of the inorganic particles include silica, calcium carbonate, aluminum hydroxide, magnesium hydroxide, clay, talc, metal oxides, etc. Examples of the material of the polymer particles include silicone resin, acrylic resin (for example, polymethacrylate resins including polymethyl methacrylate), polystyrene resin, polyurethane resin, melamine resin, polyethylene resin, epoxy resin, etc.

[0060] As the above-mentioned polymer particles, particles composed of silicone resin are preferred. In addition, as the above-mentioned inorganic particles, particles composed of metal oxides are preferred. As the above-mentioned metal oxides, titanium oxide and barium titanate are preferred, and titanium oxide is more preferred. By having such a configuration, the light diffusibility of the above-mentioned diffusion functional layer is more excellent, and uneven brightness can be further suppressed.

[0061] The shape of the above-mentioned light-diffusing particles is not particularly limited, and for example, it can be spherical, flat, or irregular.

[0062] From the viewpoint of imparting appropriate light diffusion performance, the average particle diameter of the above-mentioned light-diffusing particles is preferably 0.1 μm or more, more preferably 0.15 μm or more, further preferably 0.2 μm or more, and particularly preferably 0.25 μm or more. In addition, from the viewpoint of preventing the haze value from becoming too high and displaying a high-definition image, the average particle diameter of the above-mentioned light-diffusing particles is preferably 12 μm or less, more preferably 10 μm or less, further preferably 8 μm or less. The average particle diameter can be measured using a Coulter counter, for example.

[0063] The refractive index of the above-mentioned light-diffusing particles is preferably 1.2 to 5, more preferably 1.25 to 4.5, further preferably 1.3 to 4, and particularly preferably 1.35 to 3.

[0064] From the viewpoint of more effectively reducing the uneven brightness of the image display device, the absolute value of the refractive index difference between the above-mentioned light-diffusing particles and the resin constituting the diffusion functional layer (the resin layer other than the light-diffusing particles in the diffusion functional layer) is preferably 0.001 or more, more preferably 0.01 or more, further preferably 0.02 or more, and particularly preferably 0.03 or more, and can be 0.04 or more or 0.05 or more. In addition, from the viewpoint of preventing the haze value from becoming too high and displaying a high-definition image, the absolute value of the refractive index difference between the light-diffusing particles and the resin is preferably 5 or less, more preferably 4 or less, and further preferably 3 or less.

[0065] From the viewpoint of imparting appropriate light diffusion performance to the sheet for sealing the photoelectric semiconductor element, the content of the light-diffusing particles in the diffusion functional layer is preferably 0.01 part by mass or more, more preferably 0.05 part by mass or more, still more preferably 0.1 part by mass or more, and particularly preferably 0.15 part by mass or more, based on 100 parts by mass of the resin constituting the diffusion functional layer. Further, from the viewpoint of preventing the haze value from becoming too high and displaying a high-definition image, the content of the light-diffusing particles is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, based on 100 parts by mass of the resin constituting the diffusion functional layer.

[0066] The haze value (thickness: 50 μm) of the diffusion functional layer is not particularly limited. From the viewpoint of effectively reducing luminance unevenness, it is preferably 30% or more, more preferably 40% or more, still more preferably 50% or more, particularly preferably 60% or more, and may be 70% or more, 80% or more, 90% or more, 95% or more, 97% or more. In addition, a haze value near 99.9% is preferred because the effect of improving luminance unevenness is more excellent. It should be noted that the upper limit of the haze value of the diffusion functional layer is not particularly limited, that is, it may be 100%. The haze value may be either the value before or after curing, and the value after curing is preferred.

[0067] The total light transmittance of the diffusion functional layer is not particularly limited. From the viewpoint of ensuring luminance, it is preferably 40% or more, more preferably 60% or more, still more preferably 70% or more, particularly preferably 80% or more. In addition, the upper limit value of the total light transmittance of the diffusion functional layer is not particularly limited, and it may be less than 100%, or may be 99.9% or less or 99% or less.

[0068] The haze value and the total light transmittance of the diffusion functional layer are the values of a single layer, and can be measured by the methods specified in JIS K7136 and JIS K7361-1, and can be controlled by the type, thickness, type, and blending amount of the light-diffusing particles of the diffusion functional layer.

[0069] The haze value (thickness: 50 μm) of the non-diffusion functional layer is not particularly limited. From the viewpoint of excellent luminance, it is preferably less than 30%, more preferably 10% or less, still more preferably 5% or less, particularly preferably 1% or less, and may be 0.5% or less. It should be noted that the lower limit of the haze value of the non-diffusion functional layer is not particularly limited. The haze value may be either the value before or after curing, and the value after curing is preferred.

[0070] The total light transmittance of the above-mentioned non-diffusion functional layer is not particularly limited. From the viewpoint of ensuring brightness, it is preferably 60% or more, more preferably 70% or more, further preferably 80% or more, and particularly preferably 90% or more. In addition, the upper limit value of the total light transmittance of the above-mentioned non-diffusion functional layer is not particularly limited, and it may be less than 100%, or may be 99.9% or less or 99% or less.

[0071] The haze value and the total light transmittance of the above-mentioned non-diffusion functional layer are the values of a single layer, and can be measured by the methods specified in JIS K7136 and JIS K7361-1, and can be controlled by the type, thickness, etc. of the non-diffusion functional layer.

[0072] From the viewpoint of making the brightness of the image display device excellent, the content of the colorant and / or the light diffusing particles in the above-mentioned non-diffusion functional layer is preferably less than 0.01 parts by mass, more preferably less than 0.005 parts by mass, relative to 100 parts by mass of the resin constituting the non-diffusion functional layer.

[0073] The elastic modulus G' at 130°C before curing of the above-mentioned non-colored adhesive layer is 0.5 kPa to 10 kPa, preferably 0.6 kPa to 9 kPa, and more preferably 0.8 kPa to 8 kPa. When the elastic modulus G' is 0.5 kPa or more, the workability is excellent. When the elastic modulus G' is 10 kPa or less, the embedability or followability of the optical semiconductor element is more excellent, and when the elastic modulus G' is 9 kPa or less, the generation of voids during thermal curing is further suppressed and the reliability is more excellent.

[0074] The elastic modulus E' at room temperature (25°C) before curing of the above-mentioned non-colored adhesive layer is preferably 500 MPa to 4000 MPa, more preferably 550 MPa to 3000 MPa, and further preferably 600 MPa to 2000 MPa. When the elastic modulus E' is within the above range, the viscosity is further reduced and the workability is more excellent.

[0075] The elastic modulus E' at room temperature (25°C) after curing of the above-mentioned non-colored adhesive layer is preferably 500 MPa to 4000 MPa, more preferably 600 MPa to 3000 MPa, and further preferably 700 MPa to 2000 MPa. When the elastic modulus E' is within the above range, the viscosity is further reduced and it is less likely to cause defects.

[0076] The ratio of the elastic modulus E' at room temperature after curing of the above-mentioned non-colored adhesive layer to the elastic modulus E' at room temperature before curing [elastic modulus E' at room temperature after curing / elastic modulus E' at room temperature before curing] is preferably 0.6 to 3.1, more preferably 0.8 to 2.5, and further preferably 0.9 to 2. When the ratio is within the above range, the change in hardness before and after curing is small, and the workability and damage resistance are more excellent.

[0077] There is no particular limitation on the light transmittance at a wavelength of 600 nm after curing (thickness: 50 μm) of the above non-coloring adhesive layer. From the viewpoint of further improving the brightness of the opto-semiconductor device, it is preferably greater than 80%, more preferably 85% or more, and still more preferably 90% or more. The above light transmittance is 100% or less.

[0078] The thickness of the above non-coloring adhesive layer (the thickness of the non-coloring adhesive layer in contact with the opto-semiconductor element) is preferably 5 μm to 75 μm, more preferably 7 μm to 70 μm, and still more preferably 9 μm to 60 μm. When the above thickness is 5 μm or more, the sealing property of the opto-semiconductor element is more excellent. When the above thickness is 75 μm or less, the brightness of the opto-semiconductor device is more excellent.

[0079] (Coloring layer)

[0080] The coloring layer in the above sealing resin layer is a layer for preventing reflection of light caused by metal wirings or the like provided on the substrate in the image display device. The above coloring layer contains at least a colorant. The above coloring layer is preferably a resin layer composed of a resin, and more preferably a thermosetting adhesive layer as described above.

[0081] The above colorant only needs to be able to be dissolved or dispersed in the above coloring layer, and it can be either a dye or a pigment. From the aspect that low haze can be achieved even with a small amount of addition and it is not sedimentary like a pigment and is easily uniformly distributed, a dye is preferred. In addition, from the aspect that high color rendering property can be achieved even with a small amount of addition, a pigment is preferred. When a pigment is used as the colorant, a pigment with low conductivity or no conductivity is preferred. The above colorant can be used alone or in combination of two or more.

[0082] As the above colorant, a black-based colorant is preferred. As the above black-based colorant, known or conventional colorants (pigments, dyes, etc.) for presenting black can be used. For example, carbon black (furnace black, channel black, acetylene black, thermal cracking carbon black, lamp black, pine soot, etc.), graphite, copper oxide, manganese dioxide, aniline black, perylene black, titanium black, cyanine black, activated carbon, ferrite (non-magnetic ferrite, magnetic ferrite, etc.), magnetite, chromium oxide, iron oxide, molybdenum disulfide, chromium complex, anthraquinone-based colorant, zirconium nitride, etc. can be cited. In addition, a colorant that functions as a black-based colorant by combinatorially blending colorants that present colors other than black can be used.

[0083] When the above coloring layer is a radiation-curable resin layer, the above colorant preferably absorbs visible light and has light transmittance at a wavelength at which the above radiation-curable resin layer can be cured.

[0084] From the viewpoint of imparting an appropriate antireflection ability to the image display device, the content ratio of the colorant in the above-described colorant layer is preferably 0.03% by mass or more, more preferably 0.1% by mass or more, relative to the total amount (100% by mass) of the colorant layer. In addition, the content ratio of the colorant is, for example, 2% by mass or less, preferably 1% by mass or less, and more preferably 0.6% by mass or less. The above content ratio can be appropriately set according to the type of the colorant, the hue of the image display device, the light transmittance, and the like. The colorant can be added to the composition as a solution or dispersion dissolved or dispersed in an appropriate solvent.

[0085] The elastic modulus G' of the above-described colorant layer at 130 °C before curing is preferably 0.5 kPa to 10 kPa, more preferably 2 kPa to 9.5 kPa, and further preferably 4 kPa to 9.2 kPa. When the elastic modulus G' is within the above range, the embedability or followability of the optical semiconductor element is more excellent.

[0086] The elastic modulus E' of the above-described colorant layer at room temperature (25 °C) before curing is preferably 500 MPa to 4000 MPa, more preferably 600 MPa to 2500 MPa, and further preferably 700 MPa to 1000 MPa. When the elastic modulus E' is within the above range, the viscosity is further reduced and the workability is more excellent.

[0087] The elastic modulus E' of the above-described colorant layer (colored adhesive layer) at room temperature (25 °C) after curing is preferably 500 MPa to 4000 MPa, more preferably 600 MPa to 2500 MPa, and further preferably 700 MPa to 1000 MPa. When the elastic modulus E' is within the above range, the viscosity is further reduced and defects are less likely to occur.

[0088] The ratio [elastic modulus E' at room temperature after curing / elastic modulus E' at room temperature before curing] of the elastic modulus E' of the above-described colorant layer (colored adhesive layer) at room temperature after curing to the elastic modulus E' at room temperature before curing is preferably 0.6 to 2.0, more preferably 0.8 to 1.5, and further preferably 0.9 to 1.2. When the above ratio is within the above range, the change in hardness before and after curing is small, and the workability and damage resistance are more excellent.

[0089] The light transmittance of the above-mentioned colored layer (colored adhesive layer) after curing (thickness: 50 μm) at a wavelength of 600 nm is not particularly limited. From the viewpoints of further improving the function of preventing reflection of metal wirings, etc. in the optical semiconductor device and contrast, it is preferably 80% or less, more preferably 60% or less, further preferably 40% or less, and particularly preferably 30% or less. In addition, the above-mentioned light transmittance is 0% or more, and from the viewpoint of ensuring the brightness of the optical semiconductor device, it is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more, and may be 2.5% or more or 3% or more.

[0090] From the viewpoints of ensuring the front brightness and visual recognition when sealing the optical semiconductor element, the haze value (thickness: 50 μm) of the above-mentioned colored layer is preferably 50% or less, more preferably 40% or less, further preferably 30% or less, and particularly preferably 20% or less. In addition, from the viewpoint of effectively reducing brightness unevenness, the haze value of the above-mentioned colored layer is preferably 1% or more, more preferably 3% or more, further preferably 5% or more, and particularly preferably 8% or more, and may also be 10% or more. When the above-mentioned colored layer has curability, the haze value may be the value of either before or after curing, but the cured value is preferred.

[0091] The total light transmittance of the above-mentioned colored layer is not particularly limited. From the viewpoint of exhibiting appropriate light shielding properties, it is preferably 80% or less, more preferably 60% or less, further preferably 40% or less, and particularly preferably 30% or less. In addition, from the viewpoint of ensuring the brightness when sealing the optical semiconductor element, the total light transmittance of the above-mentioned colored layer is preferably 0.5% or more, more preferably 1% or more, further preferably 1.5% or more, and particularly preferably 2% or more, and may be 2.5% or more or 3.0% or more.

[0092] The haze value and total light transmittance of the above-mentioned colored layer are the values of a single layer, and can be measured by the methods specified in JIS K7136 and JIS K7361-1, and can be controlled by the type, thickness, type of colorant, compounding amount, etc.

[0093] The thickness of the above-mentioned colored layer (the thickness of the above-mentioned colored layer closest to the optical semiconductor element side in the above-mentioned resin layer for sealing) is preferably 10 μm to 200 μm, more preferably 20 μm to 150 μm, and further preferably 30 μm to 100 μm. When the above-mentioned thickness is 10 μm or more, the antireflection property is more excellent. When the above-mentioned thickness is 150 μm or less, the brightness of the optical semiconductor device is more excellent.

[0094] (Resin layer)

[0095] In the case where the above coloring layer and the above non-coloring adhesive layer are the above resin layer, examples of the resin constituting the above resin layer include known or conventional resins, such as acrylic resins, urethane acrylate resins, urethane resins, rubber resins, epoxy resins, epoxy acrylate resins, oxetane resins, silicone resins, silicone acrylate resins, polyester resins, polyether resins (such as polyethylene ether), polyamide resins, fluorine-containing resins, vinyl acetate / vinyl chloride copolymers, modified polyolefins, etc. The above resins may be used alone or in combination of two or more. Among them, acrylic resins are preferred. The resins of the respective layers constituting the above sealing resin layer may be the same as or different from each other.

[0096] The above acrylic resin is a resin containing a structural unit derived from an acrylic monomer (a monomer component having a (meth)acryloyl group or a structure convertible to a (meth)acryloyl group in the molecule) as a structural unit of the resin (polymer). The above acrylic resins may be used alone or in combination of two or more.

[0097] As the above acrylic resin, a resin containing the largest proportion of structural units derived from (meth)acrylate by mass ratio is preferred. It should be noted that in this specification, "(meth)acrylic acid" means "acrylic acid" and / or "methacrylic acid" (either one or both of "acrylic acid" and "methacrylic acid"), and the same applies to others.

[0098] The above resin layer preferably contains a thermosetting resin. As the above thermosetting resin, known or conventional thermosetting resins can be used, such as resins having thermosetting functional groups. Among them, as the above thermosetting resin, a thermosetting functional group-containing acrylic resin (an acrylic resin containing a thermosetting functional group) is preferred.

[0099] Examples of the above thermosetting functional groups include epoxy group-containing groups such as glycidyl groups, carboxyl groups, hydroxyl groups, isocyanate groups, aziridinyl groups, etc. Among them, a group containing an epoxy group is preferred, and a glycidyl group is more preferred. That is, as the thermosetting functional group-containing acrylic resin, an acrylic resin containing a glycidyl group is particularly preferred. The above thermosetting functional groups may have only one kind or two or more kinds.

[0100] The above-mentioned acrylic resin containing thermosetting functional groups preferably contains structural units derived from monomers having thermosetting functional groups, and more preferably contains structural units derived from acrylic monomers having thermosetting functional groups (acrylic monomers containing thermosetting functional groups). As the above-mentioned monomers having thermosetting functional groups, epoxy group-containing (meth)acrylates such as glycidyl (meth)acrylate, carboxyl group-containing monomers, acid anhydride group-containing monomers, hydroxyl group-containing (meth)acrylates, etc. can be cited.

[0101] As the above-mentioned glycidyl (meth)acrylate, for example, glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, etc. can be cited.

[0102] As the above-mentioned carboxyl group-containing monomers, for example, acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. can be cited. As the above-mentioned acid anhydride group-containing monomers, for example, maleic anhydride, itaconic anhydride, etc. can be cited.

[0103] As the above-mentioned hydroxyl group-containing (meth)acrylates, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4-hydroxymethylcyclohexyl)methyl (meth)acrylate, etc. can be cited.

[0104] As the above-mentioned acrylic monomers containing thermosetting functional groups, among them, epoxy group-containing (meth)acrylates are preferred, and glycidyl (meth)acrylate is more preferred. When the above-mentioned acrylic resin contains structural units derived from epoxy group-containing (meth)acrylates, the epoxy group acts as a thermosetting functional group, and even without adding a curing agent, the epoxy group reacts through heat curing, so that the above resin layer is cured. Therefore, the above resin layer has appropriate flexibility after heat curing, and the sealing performance of the optical semiconductor element is more excellent.

[0105] Relative to the total amount (100% by mass) of all structural units of the acrylic resin in the above resin layer, the content ratio of the structural units derived from epoxy group-containing (meth)acrylates is preferably 5% by mass to 50% by mass, and more preferably 6% by mass to 45% by mass. When the above content ratio is within the above range, the above resin layer has appropriate flexibility after heat curing, and the sealing performance of the optical semiconductor element is more excellent.

[0106] The above acrylic resin containing a thermosetting functional group may include structural units derived from other monomers than the above monomers containing a thermosetting functional group. As the above other monomers, other (meth)acrylates other than the above acrylic monomers containing a thermosetting functional group can be cited. The above other monomers may be used alone or in combination of two or more.

[0107] As the above other (meth)acrylates, for example, (meth)acrylates containing a hydrocarbon group that may have an alkoxy group can be cited. As the (meth)acrylates containing a hydrocarbon group in the above (meth)acrylates containing a hydrocarbon group that may have an alkoxy group, (meth)acrylic acid alkyl esters having a linear or branched aliphatic hydrocarbon group, (meth)acrylic acid cycloalkyl esters and other (meth)acrylates having an alicyclic hydrocarbon group can be cited; (meth)acrylic acid aryl esters and other (meth)acrylates having an aromatic hydrocarbon group can be cited, etc. The above (meth)acrylates containing a hydrocarbon group that may have an alkoxy group may be used alone or in combination of two or more.

[0108] As the above (meth)acrylic acid alkyl esters, for example, methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, isopropyl (meth)acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl (meth)acrylate, isopentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, undecyl (meth)acrylate, dodecyl (meth)acrylate (lauryl (meth)acrylate), tridecyl (meth)acrylate, tetradecyl (meth)acrylate, pentadecyl (meth)acrylate, hexadecyl (meth)acrylate, heptadecyl (meth)acrylate, octadecyl (meth)acrylate, nonadecyl (meth)acrylate, eicosyl (meth)acrylate, etc.

[0109] As the above (meth)acrylic acid alkyl esters, among them, (meth)acrylic acid alkyl esters having a linear or branched aliphatic hydrocarbon group with 1 to 20 carbon atoms (preferably 1 to 14, more preferably 2 to 10, and further preferably 2 to 8) are preferred. When the number of carbon atoms is within the above range, it is easy to make the flexibility of the above acrylic resin containing a thermosetting group during thermosetting more appropriate and the embedding property further improved.

[0110] Examples of the above (meth)acrylate having an alicyclic hydrocarbon group include: (meth)acrylates having a monocyclic aliphatic hydrocarbon ring such as cyclopentyl (meth)acrylate, cyclohexyl (meth)acrylate, cycloheptyl (meth)acrylate, cyclooctyl (meth)acrylate; (meth)acrylates having a bicyclic aliphatic hydrocarbon ring such as isobornyl (meth)acrylate; (meth)acrylates having an aliphatic hydrocarbon ring of three or more rings such as tetrahydrodicyclopentadienyl (meth)acrylate, tetrahydrodicyclopentadienyloxyethyl (meth)acrylate, tetrahydrotricyclopentadienyl (meth)acrylate, 1-adamantyl (meth)acrylate, 2-methyl-2-adamantyl (meth)acrylate, 2-ethyl-2-adamantyl (meth)acrylate, etc.

[0111] Examples of the above (meth)acrylate having an aromatic hydrocarbon group include phenyl (meth)acrylate, benzyl (meth)acrylate, etc.

[0112] Examples of the (meth)acrylate having a hydrocarbon group containing an alkoxy group include substances obtained by substituting one or more hydrogen atoms in the hydrocarbon group of the above (meth)acrylate having a hydrocarbon group with an alkoxy group, such as 2-methoxyethyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-methoxybutyl (meth)acrylate, etc.

[0113] Examples of the above other monomer components may further include polar group-containing monomers such as sulfonic acid group-containing monomers, phosphoric acid group-containing monomers, nitrogen atom-containing monomers, etc. Examples of the above sulfonic acid group-containing monomers include styrene sulfonic acid, allyl sulfonic acid, 2-(meth)acrylamido-2-methylpropanesulfonic acid, (meth)acrylamidopropanesulfonic acid, (meth)acrylic acid sulfopropyl ester, (meth)acryloxynaphthalene sulfonic acid, etc. Examples of the above phosphoric acid group-containing monomers include 2-hydroxyethyl acryloyl phosphate, etc. Examples of the above nitrogen atom-containing monomers include morpholine group-containing monomers such as (meth)acryloylmorpholine, cyano group-containing monomers such as (meth)acrylonitrile, amide group-containing monomers such as (meth)acrylamide, etc.

[0114] The above acrylic resin containing thermosetting functional groups may contain structural units derived from polyfunctional (meth)acrylates capable of copolymerizing with the monomer components constituting the acrylic resin to form a crosslinked structure in the polymer backbone. As the above polyfunctional (meth)acrylates, for example, the following can be cited: hexanediol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc. The above polyfunctional (meth)acrylates may be used alone or in combination of two or more.

[0115] The above acrylic resin containing thermosetting functional groups is obtained by polymerizing the above various monomer components. As the polymerization method, there is no particular limitation, and for example, solution polymerization method, emulsion polymerization method, bulk polymerization method, polymerization method by active energy ray irradiation (active energy ray polymerization method), etc. can be cited. In addition, the obtained acrylic resin may be any one of random copolymer, block copolymer, graft copolymer, etc.

[0116] From the viewpoints of having a certain degree of hardness after curing the above resin layer and reducing the adhesion between the sides of the optical semiconductor device, the weight average molecular weight of the above acrylic resin containing epoxy groups is preferably 2,000 to 400,000, more preferably 30,000 to 300,000. When the weight average molecular weight is within the above range, the embedability of the optical semiconductor element is more excellent. It should be noted that the above weight average molecular weight is a value measured by gel permeation chromatography (GPC) and calculated by conversion to polystyrene.

[0117] With respect to the total amount (100% by mass) of the resin in the above resin layer, the content ratio of the above acrylic resin containing epoxy groups is preferably 40% by mass or more, more preferably 50% by mass or more, and further preferably 60% by mass or more. When the above content ratio is 40% by mass or more, the embedability of the optical semiconductor element is more excellent. The above content ratio is 100% by mass or less, preferably 94% by mass or less, and more preferably 92% by mass or less.

[0118] The above resin layer preferably contains a component having a functional group (second functional group) capable of reacting with the thermosetting functional group (first functional group) in the above acrylic resin containing thermosetting functional groups by heat. The above second functional group is also a thermosetting functional group. In this case, by reacting the above first functional group with the above second functional group during heating of the resin layer, the curing of the resin layer is further promoted.

[0119] The above component having the second functional group may be the above acrylic resin containing a thermosetting functional group having the first functional group, or may be an acrylic resin containing a thermosetting functional group other than the above acrylic resin containing a thermosetting functional group having the first functional group, or may be other components having the second functional group. The above component having the second functional group may be used alone or in combination of two or more.

[0120] As the combination of the above first functional group and the above second functional group, for example, carboxyl group and epoxy group, epoxy group and carboxyl group, carboxyl group and aziridinyl group, aziridinyl group and carboxyl group, hydroxyl group and isocyanate group, isocyanate group and hydroxyl group, etc. can be cited. The above combination may be only one kind or two or more kinds.

[0121] In the case of containing the above acrylic resin containing an epoxy group, the above resin layer preferably contains a component having a functional group reactive with the epoxy group as a component of the above component having the second functional group. As the functional group reactive with the above epoxy group, carboxyl group, aziridinyl group, hydroxyl group, etc. can be cited. Among them, carboxyl group and hydroxyl group are preferred. As the above hydroxyl group, from the viewpoints of high acidity and excellent reactivity with the epoxy group, silanol group is preferred.

[0122] The above component having a carboxyl group is preferably the above resin, more preferably an acrylic resin containing a carboxyl group. When the acrylic resin containing a carboxyl group is contained, the reaction between the epoxy group and the carboxyl group in the above acrylic resin containing an epoxy group is easier to proceed even without adding a curing agent, and the sealing property of the optical semiconductor element is more excellent. In addition, the surface damage resistance is more excellent.

[0123] The above acrylic resin containing a carboxyl group preferably contains a structural unit derived from a carboxyl group-containing monomer, more preferably contains a structural unit derived from a carboxyl group-containing acrylic monomer. As the above carboxyl group-containing monomer, for example, acrylic acid, methacrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. can be cited.

[0124] With respect to the total amount (100% by mass) of all the structural units of the above acrylic resin containing a carboxyl group, the content ratio of the structural unit derived from the carboxyl group-containing acrylic monomer is preferably 1% by mass to 50% by mass, more preferably 10% by mass to 40% by mass. When the content ratio is within the above range, the above resin layer has appropriate softness after thermal curing, and the sealing property of the optical semiconductor element is more excellent.

[0125] The above carboxyl group-containing acrylic resin may include structural units derived from other monomers in addition to the above carboxyl group-containing monomers. As the above other monomers, other (meth)acrylates other than the above acrylic monomers containing thermosetting functional groups, the above polar group-containing monomers, the above polyfunctional monomers, etc. may be mentioned. The above other monomers may be used alone or in combination of two or more.

[0126] As the above other (meth)acrylates, for example, the above hydrocarbon group-containing (meth)acrylates that may have an alkoxy group can be mentioned. As the (meth)acrylic acid alkyl esters in the above hydrocarbon group-containing (meth)acrylates that may have an alkoxy group, among them, (meth)acrylic acid alkyl esters having a linear or branched aliphatic hydrocarbon group having 1 to 20 carbon atoms (preferably 1 to 14, more preferably 1 to 10, and further preferably 1 to 8) are preferred. When the number of carbon atoms is within the above range, it is easy to make the flexibility of the above thermosetting group-containing acrylic resin more appropriate and the embedding property further improved.

[0127] In order to appropriately exhibit basic properties such as adhesion to the above optical semiconductor element in the resin layer, with respect to the total amount (100% by mass) of all the structural units of the above carboxyl group-containing acrylic resin, the proportion of the above hydrocarbon group-containing (meth)acrylates that may have an alkoxy group is preferably 50% by mass to 95% by mass, more preferably 60% by mass to 90% by mass.

[0128] The weight average molecular weight of the above carboxyl group-containing acrylic resin is preferably 1,000 to 200,000, more preferably 3,000 to 100,000. When the weight average molecular weight is within the above range, the sealing property of the optical semiconductor element is more excellent. It should be noted that the above weight average molecular weight refers to the value measured by gel permeation chromatography (GPC) and calculated by polystyrene conversion.

[0129] In the case of containing the above carboxyl group-containing acrylic resin, with respect to the total amount (100% by mass) of the resin in the above resin layer, the content ratio of the above carboxyl group-containing acrylic resin is preferably 5% by mass to 60% by mass, more preferably 10% by mass to 50% by mass, and further preferably 25% by mass to 45% by mass. When the content ratio is within the above range, the thermosetting property of the resin layer is more excellent. In addition, the surface damage resistance is more excellent.

[0130] The above resin layer may contain other components in addition to the above components within the scope that does not impair the effects of the present invention. Examples of the above other components include: thermoplastic resins, coupling agents such as silane coupling agents, crosslinking promoters, tackifying resins (rosin derivatives, polyterpene resins, petroleum resins, oil-soluble phenols, etc.), oligomers, anti-aging agents, fillers (organic fillers, inorganic particles, etc.), light-diffusing particles, antioxidants, plasticizers, softeners, surfactants, antistatic agents, surface lubricants, leveling agents, light stabilizers, ultraviolet absorbers, polymerization inhibitors, granular substances, foil-like substances, etc. Each of the above other components may be used alone, or two or more thereof may be used.

[0131] With respect to the total amount (100% by mass) of the resin layer, the content ratio of the resin in the resin layer is preferably 60% by mass or more, more preferably 70% by mass or more, and further preferably 80% by mass or more. The content ratio is 100% by mass or less, may be 99.99% by mass or less, or may be 99% by mass or less, 95% by mass or less. In addition, it is preferred that the content ratio of the acrylic resin is within the above range, it is preferred that the content ratio of the thermosetting resin is within the above range, and it is preferred that the acrylic resin containing thermosetting functional groups is within the above range.

[0132] The above resin layer can be formed, for example, using a thermosetting resin composition (adhesive composition). The above resin layer can be produced, for example, by the following method: coating the adhesive composition on the release-treated surface of the release liner or the substrate to form an adhesive composition layer, and then curing the adhesive composition layer by heating to remove the solvent or radiation-induced polymerization.

[0133] Examples of the laminated structure of the above sealing resin layer include [diffusion function layer / coloring layer], [non-diffusion function layer / coloring layer], [diffusion function layer / coloring layer / non-diffusion function layer], [non-diffusion function layer / coloring layer / diffusion function layer], [diffusion function layer / coloring layer / diffusion function layer], [non-diffusion function layer / coloring layer / non-diffusion function layer] (the above are in order from the light semiconductor element side), etc.

[0134] (Substrate part)

[0135] In the sheet for sealing an optical semiconductor element of the present invention, the above-mentioned sealing resin layer may be provided on at least one surface of the base material portion. That is, the above-mentioned sheet for sealing a semiconductor element may have a base material portion and the above-mentioned sealing resin layer provided on at least one surface of the above-mentioned base material portion. When the sheet for sealing an optical semiconductor element of the present invention has the above-mentioned base material portion, the side of the above-mentioned sealing resin layer opposite to the side in contact with the optical semiconductor element becomes the side in contact with the base material portion. When the above-mentioned base material portion is provided on the side of the sealing resin layer opposite to the optical semiconductor element side in the above-mentioned sheet for sealing an optical semiconductor element, the surface of the sealing resin layer can be made flat, thereby making it difficult to cause diffuse reflection of light, and improving the aesthetic appearance of the optical semiconductor device in both the extinguished state and the light-emitting state. In addition, by forming an antiglare layer and an antireflection layer described later on the above-mentioned base material portion, antiglare properties and antireflection properties can be imparted to the optical semiconductor device. In addition, in the above-mentioned sheet for sealing an optical semiconductor element, the base material portion serves as a support for the sealing resin layer, and by having the above-mentioned base material portion, the operability of the sheet for sealing an optical semiconductor element is excellent. It should be noted that it is not necessary to provide a base material portion.

[0136] The above-mentioned base material portion may be a single layer or multiple layers that are the same or different in composition, thickness, etc. When the above-mentioned base material portion is multiple layers, each layer may be bonded by other layers such as an adhesive layer. It should be noted that the base material layer for the base material portion is the part that is pasted to the adherend together with the above-mentioned sealing resin layer, and the release liner that is peeled off when using the sheet for sealing an optical semiconductor element (during pasting) and the surface protective film that only protects the surface of the base material portion are not included in the "base material portion".

[0137] As the base material layer constituting the above-mentioned base material part, examples include: glass, plastic base materials (especially plastic films), etc. As the resin constituting the above-mentioned plastic base material, examples include: low-density polyethylene, linear low-density polyethylene, medium-density polyethylene, high-density polyethylene, ultra-low-density polyethylene, random copolymer polypropylene, block copolymer polypropylene, homopolypropylene, polybutene, polymethylpentene, ionomer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylate (random, alternating) copolymer, ethylene-vinyl acetate copolymer (EVA), ethylene-propylene copolymer, cyclic olefin polymer, ethylene-butene copolymer, ethylene-hexene copolymer and other polyolefin resins; polyurethane; polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate (PBT) and other polyesters; polycarbonate; polyimide resins; polyether ether ketone; polyetherimide; polyamides such as aromatic polyamide and wholly aromatic polyamide; polyphenylene sulfide; fluorine-containing resins; polyvinyl chloride; polyvinylidene chloride; cellulose resins such as triacetyl cellulose (TAC); silicone resins; acrylic resins such as polymethyl methacrylate (PMMA); polysulfone; polyarylate; polyvinyl acetate, etc. The above resins can be used alone or in combination of two or more. The above base material layer can be various optical films such as an antireflection (AR) film, a polarizer, a retardation plate, etc.

[0138] The thickness of the above plastic film is preferably 20 μm to 300 μm, more preferably 40 μm to 250 μm. When the above thickness is 20 μm or more, the supportability and operability of the sheet for sealing an optical semiconductor element are further improved. When the above thickness is 300 μm or less, the sheet for sealing an optical semiconductor element can be further thinned.

[0139] In order to improve the adhesion, retention, etc. with the sealing resin layer, the surface on the side where the above sealing resin layer is provided of the above base material part can be subjected to physical treatments such as corona discharge treatment, plasma treatment, sandblasting treatment, ozone exposure treatment, flame exposure treatment, high-voltage electric shock exposure treatment, ionizing radiation treatment, etc.; chemical treatments such as chromic acid treatment; surface treatments such as easy adhesion treatment using a coating agent (primer). The surface treatment for improving adhesion is preferably carried out on the entire surface on the side of the sealing resin layer in the base material part.

[0140] From the viewpoint of excellent functions as a support and scratch resistance of the surface, the thickness of the above base material part is preferably 5 μm or more, more preferably 10 μm or more. From the viewpoint of more excellent transparency, the thickness of the above base material part is preferably 300 μm or less, more preferably 250 μm or less.

[0141] <Sheet for Sealing an Optical Semiconductor Element>

[0142] The sheet for sealing an optical semiconductor device may include a layer having antiglare property and / or antireflection property. By having such a structure, it is possible to suppress gloss and reflection of light when sealing the optical semiconductor device, resulting in a better appearance. Examples of the layer having antiglare property include an antiglare treatment layer. Examples of the layer having antireflection property include an antireflection treatment layer. The antiglare treatment and the antireflection treatment can be respectively carried out by known or conventional methods. The layer having antiglare property and the layer having antireflection property may be the same layer or different layers. The layer having antiglare property and / or antireflection property may have only one layer or two or more layers. The layer having antiglare property and / or antireflection property is preferably provided on the surface (preferably the surface) of the sheet for sealing an optical semiconductor device on the side opposite to the side in contact with the optical semiconductor device with respect to the sealing resin layer.

[0143] The haze value of the sheet for sealing an optical semiconductor device is not particularly limited. From the viewpoints of more excellent effects of suppressing brightness unevenness and designability, it is preferably 0.5% or more, more preferably 1% or more, and further preferably 3% or more. It should be noted that the upper limit of the haze value is not particularly limited and may be 100%, or may be 80%, 60%, or 40%. The haze value may be the value of either before or after curing, and preferably the value after curing.

[0144] The total light transmittance of the sheet for sealing an optical semiconductor device is not particularly limited. From the viewpoints of further enhancing the function of preventing reflection of metal wirings, etc. and improving the contrast, it is preferably 40% or less, more preferably 30% or less, and further preferably 20% or less. In addition, from the viewpoint of ensuring brightness, the total light transmittance is preferably 0.5% or more.

[0145] The haze value and the total light transmittance can be respectively measured by the methods specified in JIS K7136 and JIS K7361-1, and can be controlled by the lamination sequence, types, thicknesses, etc. of the respective layers constituting the sealing resin layer and the base material portion.

[0146] In the state where the optical semiconductor device is sealed with the sheet for sealing an optical semiconductor device, the distance from the optical semiconductor device to the non-colored adhesive layer (the non-colored adhesive layer closest to the optical semiconductor device side in the sealing resin layer) is preferably 0 μm to 20 μm, more preferably 0 to 10 μm. When the distance is within the above range, the antireflection property and brightness of the image display device are more excellent.

[0147] From the viewpoints of improving the function of preventing reflection of metal wirings and the like, contrast, and more effectively reducing color shift, the thickness of the above-mentioned sheet for sealing an optical semiconductor element is preferably 5 μm to 600 μm, more preferably 10 μm to 550 μm, still more preferably 30 μm to 500 μm, still more preferably 40 μm to 450 μm, and particularly preferably 50 μm to 400 μm. It should be noted that the release liner is not included in the above thickness.

[0148] The thickness of the above-mentioned resin layer for sealing is, for example, 5 μm to 500 μm, preferably 10 μm to 400 μm, and still more preferably 100 μm to 300 μm. When the above thickness is 5 μm or more, the sealing property of the optical semiconductor element becomes better. When the above thickness is 500 μm or less, the thickness of the optical semiconductor device is thinner.

[0149] [Release liner]

[0150] The above-mentioned resin layer for sealing can be formed on the release-treated surface of the release liner. When the above-mentioned resin layer for sealing is formed on the above-mentioned release liner, the non-colored adhesive layer (the non-colored adhesive layer closest to the optical semiconductor element side in the above-mentioned resin layer for sealing) of the above-mentioned resin layer for sealing becomes the side in contact with the above-mentioned release liner. In the case of not having the above-mentioned base material portion, both sides of the above-mentioned resin layer for sealing can be the sides in contact with the release liner. The release liner is used as a protective material for the above-mentioned sheet for sealing an optical semiconductor element and is peeled off when sealing the optical semiconductor element. It should be noted that it is not necessary to provide a release liner.

[0151] The above-mentioned release liner is an element for covering and protecting the surface of the above-mentioned sheet for sealing an optical semiconductor element, and the release liner is peeled off from the sheet when the sheet for sealing an optical semiconductor element is attached to a substrate on which an optical semiconductor element is disposed.

[0152] Examples of the above-mentioned release liner include plastic films such as polyethylene terephthalate (PET) films, polyethylene films, and polypropylene films, and papers that are surface-coated with a release agent such as a fluorine-containing release agent or a long-chain alkyl acrylate release agent.

[0153] The thickness of the above-mentioned release liner is, for example, 10 μm to 200 μm, preferably 15 μm to 150 μm, and more preferably 20 μm to 100 μm. When the above thickness is 10 μm or more, it is not easily broken due to cutting during the processing of the release liner. When the above thickness is 200 μm or less, it is easy to peel off the release liner from the above-mentioned sheet for sealing an optical semiconductor element during use.

[0154] Figure 1 It is a cross-sectional view showing an embodiment of the sheet for sealing an optical semiconductor element of the present invention. As Figure 1As shown, the sheet 1 for sealing an opto-semiconductor element can be used to seal one or more opto-semiconductor elements disposed on a substrate, and has a base material portion 4 and a sealing resin layer 2 formed on the base material portion 4. The base material portion 4 is composed of a base material film 41 and a functional layer 42 as a surface treatment layer, but it may also be composed of only the base material film 41 without the functional layer 42.

[0155] In Figure 1 the sheet 1 for sealing an opto-semiconductor element shown, the sealing resin layer 2 is formed by a laminate of a non-colored adhesive layer 21 and a colored layer 22. The colored layer 22 is directly laminated on the non-colored adhesive layer 21. A release liner 3 is adhered to the non-colored adhesive layer 21, and the base material portion 4 is adhered to the colored layer 22. The non-colored adhesive layer 21 is a thermosetting adhesive layer. The colored layer 22 is preferably a thermosetting adhesive layer.

[0156] In Figure 1 it, the functional layer 42 is a layer not included in the above-mentioned sealing resin layer, and examples of the layer that can impart various functions to the sheet for sealing an opto-semiconductor element can be cited. As the above-mentioned functional layer, for example, a layer including a surface treatment layer can be cited. By having such a configuration, the sheet for sealing an opto-semiconductor element laminated with a functional layer including a surface treatment layer has excellent light diffusion properties and excellent light extraction efficiency. As the above-mentioned surface treatment layer, an antiglare treatment layer (antiglare treatment layer), an antireflection treatment layer, a hard coat treatment layer, etc. can be cited. The above-mentioned functional layer can be laminated on the above-mentioned sealing resin layer in the above-mentioned sheet for sealing an opto-semiconductor element, and in the case of having the above-mentioned base material portion, it can be laminated on the above-mentioned base material portion, preferably laminated on the above-mentioned base material portion, and preferably laminated on the side of the above-mentioned base material portion opposite to the side where the above-mentioned sealing resin layer is provided.

[0157] [Manufacturing method of sheet for sealing opto-semiconductor element]

[0158] An embodiment of the manufacturing method of the above-mentioned sheet for sealing an opto-semiconductor element will be described. For example, regarding Figure 1The sheet 1 for sealing an optical semiconductor element shown is provided with an uncolored adhesive layer 21 and a colored layer 22, each sandwiched between the release-treated surfaces of two release liners. One of the release liners adhered to the uncolored adhesive layer 21 is the release liner 3. Next, one of the release liners adhered to the colored layer 22 is peeled off, thereby exposing the surface of the colored layer 22, and the exposed surface is adhered to the base material portion 4. Then, one of the release liners (the release liner other than the release liner 3) adhered to the uncolored adhesive layer 21 is peeled off, and the exposed surface of the uncolored adhesive layer 21 is adhered to the surface of the colored layer 22 exposed by peeling off the release liner on the surface of the colored layer 22. It should be noted that the lamination of various layers can be performed using a known roller or laminator. By operating in this way, it is possible to fabricate the sheet 1 for sealing an optical semiconductor element shown in which the colored layer 22, the uncolored adhesive layer 21, and the release liner 3 are laminated in this order on the base material portion 4. Figure 1 The sheet 1 for sealing an optical semiconductor element shown.

[0159] [Optical semiconductor device]

[0160] The above sheet for sealing an optical semiconductor element can be used to fabricate an optical semiconductor device such as an image display device. The optical semiconductor device fabricated using the above sheet for sealing an optical semiconductor element includes: a substrate, an optical semiconductor element disposed on the substrate, and the above sheet for sealing an optical semiconductor element or a cured product obtained by curing the sheet. The cured product is a cured product obtained by thermally curing the uncolored adhesive layer 21 (or also the colored layer 22) having thermosetting properties possessed by the above sheet for sealing an optical semiconductor element. Specifically, it has a cured sealing layer obtained by thermally curing the uncolored adhesive layer 21.

[0161] Examples of the above optical semiconductor element include light-emitting diodes (LEDs) such as blue light-emitting diodes, green light-emitting diodes, red light-emitting diodes, and ultraviolet light-emitting diodes.

[0162] In the above optical semiconductor device, the sheet for sealing an optical semiconductor element has excellent followability to unevenness when the optical semiconductor element is a convex portion and the gaps between multiple optical semiconductor elements are concave portions, and excellent followability and embedability of the optical semiconductor element. Therefore, it is preferable to seal multiple optical semiconductor elements together.

[0163] Figure 2 Indicates an embodiment of an optical semiconductor device using the Figure 1 Sheet 1 for sealing an optical semiconductor element shown. Figure 2The optical semiconductor device 10 shown has: a substrate 5, a plurality of optical semiconductor elements 6 disposed on one surface of the substrate 5, and a cured product of the optical semiconductor element sealing sheet 1. The cured product of the optical semiconductor element sealing sheet is an object obtained by peeling the release liner 3 from the optical semiconductor element sealing sheet 1 and forming a cured sealing layer 7 formed by thermally curing the non-colored adhesive layer 21. For example, the cured sealing layer 7 includes a non-colored adhesive layer 71 formed by thermally curing the non-colored adhesive layer 21 and a colored layer 72 formed by thermally curing the colored layer 22. The plurality of optical semiconductor elements 6 are uniformly sealed by the cured sealing layer 7. The cured sealing layer 7 follows the uneven shape formed by the plurality of optical semiconductor elements 6 and adheres to the optical semiconductor elements 6 and the substrate 5, and buries the optical semiconductor elements 6 therein. Further, the cured sealing layer 7 follows the above uneven shape, so that the interface on the optical semiconductor element 6 side has an uneven shape and the other interface is flat.

[0164] It should be noted that in Figure 2 the optical semiconductor device 10 shown, the optical semiconductor element 6 is completely buried in the non-colored adhesive layer 71 and sealed, and is indirectly sealed by the colored layer 72. That is, the optical semiconductor element 6 is sealed by the cured sealing layer 7 of the laminate including the non-colored adhesive layer 71 and the colored layer 72. The above optical semiconductor device is not limited to such a manner. For example, it may be as shown in Figure 3 wherein the optical semiconductor element 6 is completely buried in the non-colored adhesive layer 71 and the colored layer 72 and sealed.

[0165] As described above, the above optical semiconductor device seals the optical semiconductor element therein through the cured sealing layer. The thermosetting adhesive layer has sufficient flexibility before thermal curing, so it has excellent uneven following property, sufficiently buries the optical semiconductor element therein, and fixes the optical semiconductor element after thermal curing. Therefore, the optical semiconductor element adheres to the cured sealing layer, and the sealing property of the optical semiconductor element is excellent. In addition, the adhesiveness of the side surface of the thermosetting adhesive layer is low, so the workability is excellent. Further, in the spliced state, when separating adjacent optical semiconductor devices from each other, they can be easily separated, and it is not easy to cause chip defects or adhesion of the chips of adjacent optical semiconductor devices.

[0166] The above optical semiconductor device can be formed by splicing individual optical semiconductor devices. That is, the above optical semiconductor device can be an optical semiconductor device in which a plurality of optical semiconductor devices are arranged in a tile shape in the planar direction.

[0167] Figure 4 Shows an embodiment of an optical semiconductor device fabricated by arranging a plurality of optical semiconductor devices. In Figure 4In the optical semiconductor device 20 shown, a plurality of optical semiconductor devices 10 are arranged in a tile shape (patched) in the planar direction, with 4 arranged longitudinally and 4 arranged transversely, for a total of 16 optical semiconductor devices. At the boundary 20a between two adjacent optical semiconductor devices 10, the optical semiconductor devices 10 are adjacent to each other, but they can be easily separated, and it is not easy to cause defects on the side surface of the cured sealing layer 7 or the adhesion of the resin with defects on the side surface of the cured sealing layer 7 from one adjacent optical semiconductor device to the other.

[0168] The above image display device preferably has a self-luminous display device. In addition, by combining the above self-luminous display device and a display panel as needed, an image display device can be formed. The optical semiconductor element in this case is an LED element. Examples of the above self-luminous display device include: an LED display, a backlight, or an organic electroluminescent (organic EL) display device, etc. The above backlight is particularly preferably a direct-lit full-surface backlight. The above backlight, for example, includes a laminate having the above substrate and a plurality of optical semiconductor elements disposed on the substrate as at least a part of the constituent members. For example, in the above self-luminous display device, a metal wiring layer for sending a light emission control signal to each LED element is laminated on the above substrate. Each LED element that emits red (R), green (G), and blue (B) light is alternately arranged on the substrate with the metal wiring layer therebetween. The metal wiring layer is formed of a metal such as copper, and each LED element is adjusted in light emission degree to display various colors.

[0169] The above sheet for sealing an optical semiconductor element can be used for an optical semiconductor device having a bent use, such as an optical semiconductor device of a bendable image display device (flexible display) (especially a foldable image display device (foldable display)). Specifically, it can be used for a foldable backlight and a foldable self-luminous display device, etc.

[0170] Since the above sheet for sealing an optical semiconductor element has excellent followability and embedability of the optical semiconductor element, it can be preferably used in either the case where the above optical semiconductor device is a small LED display device or the case where it is a micro-LED display device.

[0171] [Manufacturing method of optical semiconductor device]

[0172] The above-mentioned opto-semiconductor device can be manufactured, for example, by a manufacturing method having the following processes: a process (sealing process) of bonding the above-mentioned opto-semiconductor element sealing sheet to the above-mentioned opto-semiconductor element provided on the above-mentioned substrate and sealing the above-mentioned opto-semiconductor element with the above-mentioned sealing resin layer; a process (heating process) of heating a laminate including the above-mentioned substrate obtained through the above-mentioned sealing process, the opto-semiconductor element disposed on the above-mentioned substrate, and the above-mentioned opto-semiconductor element sealing sheet that seals the above-mentioned opto-semiconductor element to cure the above-mentioned non-coloring adhesive layer, thereby obtaining the above-mentioned cured product. The above-mentioned cured product is a cured product obtained by thermally curing the above-mentioned non-coloring adhesive layer. Specifically, it has a cured sealing layer obtained by thermally curing the above-mentioned non-coloring adhesive layer.

[0173] The above-mentioned manufacturing method may further have a process (cutting process) of cutting the above-mentioned laminate obtained through the above-mentioned heating process to obtain an opto-semiconductor device. In addition, the above-mentioned manufacturing method may further have a splicing process of arranging a plurality of opto-semiconductor devices obtained in the above-mentioned cutting process in contact with each other in a planar direction. Hereinafter, reference will be appropriately made to Figure 2 the manufacturing method of the opto-semiconductor device 10 shown and Figure 4 the manufacturing method of the opto-semiconductor device 20 shown for explanation.

[0174] (Sealing process)

[0175] In the method of manufacturing an opto-semiconductor device using the above-mentioned opto-semiconductor element sealing sheet, there is a sealing process of bonding the above-mentioned opto-semiconductor element sealing sheet to a substrate on which an opto-semiconductor element is disposed and sealing the opto-semiconductor element with a sealing resin layer. In the above-mentioned sealing process, specifically, first, the release liner is peeled off from the above-mentioned opto-semiconductor element sealing sheet to expose the sealing resin layer. Then, the exposed surface of the above-mentioned opto-semiconductor element sealing sheet is bonded to the substrate surface of the laminate (such as an optical member) having a substrate and an opto-semiconductor element (preferably a plurality of opto-semiconductor elements) disposed on the above-mentioned substrate. When the laminate has a plurality of opto-semiconductor elements, the above-mentioned sealing resin layer is further disposed in such a way as to fill the gaps between the plurality of opto-semiconductor elements, thereby sealing the plurality of opto-semiconductor elements together. Specifically, the non-coloring adhesive layer 21 exposed by peeling the release liner 3 from the Figure 1 opto-semiconductor element sealing sheet 1 shown is disposed so as to face the surface of the substrate 5 on which the opto-semiconductor element 6 is disposed. The opto-semiconductor element sealing sheet 1 is bonded to the surface of the substrate 5 on which the opto-semiconductor element 6 is disposed, and the opto-semiconductor element 6 is buried in the sealing resin layer 2 or the sealing resin layer 2 follows and adheres to the opto-semiconductor element 6.

[0176] The temperature during the above-mentioned bonding is, for example, in the range of room temperature to 150°C. In addition, during the above-mentioned bonding, reduced pressure or increased pressure can be applied. By applying reduced pressure or increased pressure, the formation of voids between the sealing resin layer and the substrate or the opto-semiconductor element can be suppressed. Further, in the above-mentioned sealing process, it is preferable to bond the opto-semiconductor element sealing sheet under reduced pressure and then apply pressure. The pressure in the case of reduced pressure is, for example, 1 Pa to 100 Pa, and the reduced pressure time is, for example, 5 seconds to 600 seconds. In addition, the pressure in the case of applying pressure is, for example, 0.05 MPa to 0.5 MPa, and the pressurization time is, for example, 5 seconds to 600 seconds.

[0177] (Heating process)

[0178] In the above-mentioned heating process, the laminate in which the opto-semiconductor element sealing sheet is bonded to the substrate on which the above-mentioned opto-semiconductor element is disposed (for example, the laminate obtained in the above-mentioned sealing process) is heated to cure the non-coloring adhesive layer, and the coloring layer is cured as needed. Specifically, in the above-mentioned heating process, as Figure 2 shown, the non-coloring adhesive layer 21 is cured to form a cured sealing layer 7, thereby obtaining a cured product of the opto-semiconductor element sealing sheet 1. The temperature during the above-mentioned heating is, for example, in the range of 80°C to 200°C, and the heating time is, for example, 1 minute to 24 hours.

[0179] (Cutting process)

[0180] In the above-mentioned cutting process, the laminate that has undergone the above-mentioned heating process is cut. Here, in the laminate supplied to the cutting process, the cured product of the opto-semiconductor element sealing sheet and the substrate 5 extend wider in the plane direction than the finally obtained opto-semiconductor device 10. Then, in the above-mentioned cutting process, the side ends of the cured product of the opto-semiconductor element sealing sheet and the substrate are cut off. The above-mentioned cutting can be performed by a known or conventional method, for example, by using a cutting blade or laser irradiation. By operating in this way, for example, it is possible to manufacture Figure 3 the opto-semiconductor device 10 shown.

[0181] (Splicing process)

[0182] In the above-mentioned splicing process, a plurality of opto-semiconductor devices obtained in the above-mentioned cutting process are arranged and spliced so as to be in contact with each other in the plane direction. By operating in this way, for example, it is possible to manufacture Figure 4 the opto-semiconductor device 20 shown (for example, a large image display device). The sealing performance of the opto-semiconductor elements in the opto-semiconductor device obtained by splicing is excellent, and when the adjacent opto-semiconductor devices are pulled apart from each other, it is not easy to cause damage to the sheet or adhesion of the sheets of the adjacent opto-semiconductor devices.

[0183] Examples

[0184] The following are examples for a more detailed description of the present invention, but the present invention is not limited by any of these examples.

[0185] Preparation Example 1

[0186] (Production of non - colored adhesive layer 1)

[0187] 60 parts by mass of acrylic polymer A1 (glycidyl methacrylate (GMA): ethyl acrylate (EA): butyl methacrylate (BMA) = 34% by mass: 30% by mass: 36% by mass, weight - average molecular weight 60,000), 37 parts by mass of acrylic resin B (trade name “UC - 3000”, carboxyl - containing acrylic resin, manufactured by Toagosei Co., Ltd.), and 3 parts by mass of a silane coupling agent (trade name “KBM - 303”, manufactured by Shin - Etsu Chemical Co., Ltd.) were dissolved in methyl ethyl ketone, thereby preparing a resin composition solution 1 with a solid - content concentration of 50% by mass. The above resin composition solution 1 was coated on the release - treated surface of a release liner (a release - treated film comprising a poly(ethylene terephthalate) film with a thickness of 38 μm subjected to a polysiloxane release treatment), and then dried at 130°C for 2 minutes, thereby producing a sheet - shaped thermosetting resin composition (non - colored adhesive layer 1) with a thickness (average thickness) of 10 μm.

[0188] Preparation Example 2

[0189] (Production of non - colored adhesive layer 2)

[0190] 91 parts by mass of acrylic polymer A2 (glycidyl methacrylate (GMA): ethyl acrylate (EA): butyl methacrylate (BMA) = 34% by mass: 26% by mass: 40% by mass, weight - average molecular weight 100,000), 6 parts by mass of acrylic resin B (trade name “UC - 3000”, carboxyl - containing acrylic resin, manufactured by Toagosei Co., Ltd.), and 3 parts by mass of a silane coupling agent (trade name “KBM - 303”, manufactured by Shin - Etsu Chemical Co., Ltd.) were dissolved in methyl ethyl ketone, thereby preparing a resin composition solution 2 with a solid - content concentration of 50% by mass. The above resin composition solution 2 was coated on the release - treated surface of a release liner (a release - treated film comprising a poly(ethylene terephthalate) film with a thickness of 38 μm subjected to a polysiloxane release treatment), and then dried at 130°C for 2 minutes, thereby producing a sheet - shaped thermosetting resin composition (non - colored adhesive layer 2) with a thickness (average thickness) of 50 μm.

[0191] Preparation Example 3

[0192] (Production of non - colored adhesive layer 3)

[0193] 95 parts by mass of an acrylic polymer A2 (glycidyl methacrylate (GMA): ethyl acrylate (EA): butyl methacrylate (BMA) = 34% by mass: 26% by mass: 40% by mass, weight-average molecular weight 100,000), 2 parts by mass of an acrylic resin B (trade name “UC-3000”, a carboxyl group-containing acrylic resin, manufactured by Toagosei Co., Ltd.), and 3 parts by mass of a silane coupling agent (trade name “KBM-303”, manufactured by Shin-Etsu Chemical Co., Ltd.) were dissolved in methyl ethyl ketone to prepare a resin composition solution 3 having a solid content concentration of 50% by mass. The resin composition solution 3 was coated on the release-treated surface of a release liner (a release-treated film including a 38-μm-thick polyethylene terephthalate film subjected to a polysiloxane release treatment), and then dried at 130° C. for 2 minutes to produce a sheet-like thermosetting resin composition (non-colored adhesive layer 3) having a thickness (average thickness) of 50 μm.

[0194] Production Example 4

[0195] (Production of non-colored adhesive layer 1)

[0196] 95 parts by mass of butyl acrylate (BA), 5 parts by mass of acrylic acid, 249 parts by mass of ethyl acetate as a solvent, and 0.2 parts by mass of azobisisobutyronitrile were mixed to obtain a monomer composition. The obtained monomer composition was put into a polymerization experimental apparatus equipped with a separable lid, a separatory funnel, a thermometer, a nitrogen introduction tube, a Liebig condenser, a vacuum seal, a stirrer, and a stirring blade on a 1-L round-bottom separable flask, and nitrogen replacement was performed while stirring. Then, under the condition of introducing nitrogen, the mixture was maintained at 65° C. for 4 hours while stirring, and then maintained at 75° C. for 2 hours to carry out polymerization, thereby obtaining a polymer A. 0.4 parts by mass of a crosslinking agent (trade name “CORONATE HX”, manufactured by Tosoh Corporation) and 0.01 parts by mass of a catalyst (trade name “Narsem Second Iron”, manufactured by Nippon Chemical Industry Co., Ltd.) were added to 100 parts by mass of the polymer A to obtain an adhesive composition. The adhesive composition was coated on the release-treated surface of a release liner (a release-treated film including a 38-μm-thick polyethylene terephthalate film subjected to a polysiloxane release treatment), and then dried at 130° C. for 3 minutes to produce a sheet-like adhesive layer having a thickness (average thickness) of 50 μm. Three sheets of the adhesive layer were overlapped to obtain a thermoplastic resin composition (non-colored adhesive layer 1) having a thickness of 150 μm.

[0197] Production Example 5

[0198] (Production of colored adhesive layer 1)

[0199] 64.55 parts by mass of an acrylic polymer A2 (glycidyl methacrylate (GMA): ethyl acrylate (EA): butyl methacrylate (BMA) = 34% by mass: 26% by mass: 40% by mass, weight average molecular weight 100,000), 32 parts by mass of an acrylic resin B (trade name “UC-3000”, a carboxyl group-containing acrylic resin, manufactured by Toagosei Co., Ltd.), 0.3 parts by mass of “carbon black #20” (Mitsubishi Chemical Corporation), and 3 parts by mass of a silane coupling agent (trade name “KBM-303”, manufactured by Shin-Etsu Chemical Co., Ltd.) were dissolved in methyl ethyl ketone, whereby a resin composition solution 5 having a solid content concentration of 50% by mass was prepared. The resin composition solution 5 was coated on the release-treated surface of a release liner (a release-treated film comprising a polyethylene terephthalate film having a thickness of 38 μm and subjected to a polysiloxane release treatment), and then dried at 130° C. for 2 minutes, whereby a sheet-like thermosetting resin composition (colored adhesive layer 1) having a thickness (average thickness) of 50 μm was produced.

[0200] Production Example 6

[0201] (Production of Colored Adhesive Layer 2)

[0202] A sheet-like thermosetting resin composition (colored adhesive layer 2) was produced in the same manner as in Production Example 5, except that the thickness (average thickness) was 80 μm.

[0203] Production Example 7

[0204] (Production of Colored Adhesive Layer 3)

[0205] A sheet-like thermosetting resin composition (colored adhesive layer 3) was produced in the same manner as in Production Example 5, except that the thickness (average thickness) was 160 μm.

[0206] Examples 1 to 4, Comparative Example 1

[0207] As shown in Table 1, the exposed surfaces of the layers (resin compositions) obtained in each production example were bonded to each other, whereby a sealing sheet for each example was produced.

[0208] (Evaluation)

[0209] The following evaluations were performed on the resin compositions and the obtained sealing sheets used in the examples and comparative examples. The results are shown in Table 1.

[0210] (1) Storage Modulus G’ at 130° C. before Curing

[0211] The resin compositions obtained in the Preparation Examples were laminated to produce a laminate of the resin composition with a thickness of about 300 μm, which was then punched into a cylindrical shape with a diameter of φ8 mm to obtain a measurement sample. Using a rheometer (trade name: "HAAKE MARS III Rheometer", manufactured by Thermo SCIENTIFIC), the above measurement sample was measured in a shear mode at a frequency of 1 Hz in the temperature range of 80 °C to 160 °C at a heating rate of 5 °C per minute, and the storage modulus G' at 130 °C was calculated.

[0212] (2) Tensile storage modulus E' at room temperature (25 °C) before curing

[0213] The resin compositions obtained in the Preparation Examples were overlapped to a thickness of 200 μm at 60 °C, and then cut into strips with a width of 10 mm and a length of 40 mm using a cutter to obtain a measurement sample. Using a solid viscoelasticity measuring device (trade name: "RSA III", manufactured by Rheometric Scientific), in a tensile mode, at a frequency of 1 Hz and a distance between chucks of 22.5 mm, the above measurement sample was measured in the temperature range of -10 °C to 250 °C at a heating rate of 5 °C per minute to measure the dynamic storage modulus, and the tensile storage modulus E' at 25 °C was calculated.

[0214] (3) Tensile storage modulus E' at room temperature (25 °C) after curing

[0215] The resin compositions obtained in the Preparation Examples were overlapped to a thickness of 200 μm at 60 °C, cut into strips with a width of 10 mm and a length of 40 mm using a cutter, and heated at 150 °C for 1 hour to cure them, thereby obtaining a measurement sample. Using a solid viscoelasticity measuring device (trade name: "RSA III", manufactured by Rheometric Scientific), in a tensile mode, at a frequency of 1 Hz and a distance between chucks of 22.5 mm, the above measurement sample was measured in the temperature range of -10 °C to 250 °C at a heating rate of 5 °C per minute to measure the dynamic storage modulus, and the tensile storage modulus E' at 25 °C was calculated.

[0216] (4) Light transmittance after curing

[0217] For the resin compositions obtained in the Preparation Examples, a resin composition with a thickness of 50 μm was separately prepared in the same manner, and then heated at 150 °C for 1 hour to cure it, thereby obtaining a measurement sample. Then, using an ultraviolet-visible-near-infrared spectrophotometer (trade name: "V-670 DS", manufactured by JASCO Corporation) and an integrating sphere unit, the total transmittance spectrum in the wavelength range of 300 nm to 2000 nm was measured, and the transmittance at a wavelength of 600 nm was read from the obtained spectrum.

[0218] (5) Haze value

[0219] For the resin composition obtained in the preparation examples and the sealing sheets obtained in the examples and comparative examples, sheets with a thickness of 50 μm were separately prepared in the same manner, then cured by heating at 150 °C for 1 hour, and further stored at 125 °C for 1000 hours to obtain measurement samples. Then, they were placed in the sample chamber of a haze meter (trade name "NDHG2000", manufactured by Nippon Denshoku Industries Co., Ltd.), and the haze value was measured using a D65 light source.

[0220] (6) Appearance (flatness)

[0221] Using a vacuum pressing device, the sealing sheets obtained in the examples and comparative examples were used to seal a patterned wafer with a height of 10 μm, a longitudinal length of 30 μm, and a lateral length of 15 μm at 130 °C × 0.3 MPa × 600 seconds to prepare samples after thermal curing at 150 °C for 1 hour. For the surface of the release liner, the height of the surface undulation was measured using Dekak, and the difference between the maximum and minimum values of the surface undulation was measured. Then, the appearance was evaluated based on the following evaluation criteria.

[0222] [Evaluation criteria]

[0223] ◎: The difference between the maximum and minimum values of the surface undulation is 2 μm or less

[0224] 〇: The difference between the maximum and minimum values of the surface undulation is greater than 2 μm and less than or equal to 4 μm

[0225] ×: The difference between the maximum and minimum values of the surface undulation is greater than 4 μm.

[0226] (7) Antireflection property

[0227] The release liner on the optoelectronic device side of the sealing sheets obtained in the examples and comparative examples was peeled off, and the exposed surface was attached to an aluminum foil to prepare samples. The obtained samples were set in a product named "SolidSpec3700" (manufactured by Shimadzu Corporation) with the release liner on the side opposite to the optoelectronic device side as the light source side, and the reflectance (%) at 280 nm to 780 nm was measured. Then, the antireflection property was evaluated based on the following evaluation criteria.

[0228] [Evaluation criteria]

[0229] ◎: The reflectance at 550 nm is 8.5% or less

[0230] 〇: The reflectance at 550 nm is greater than 8.5% and less than or equal to 10%

[0231] △: The reflectance at 550 nm is greater than 10% and less than or equal to 25%

[0232] ×: Reflectance at 550 nm is greater than 25%.

[0233] (8) Workability

[0234] The sealed samples prepared in the above appearance evaluation were cut into a size of 10 mm × 10 mm, and the protrusion amount and the climbing amount of the resin from the wafer edge were evaluated. Then, the workability was evaluated based on the following evaluation criteria.

[0235] Evaluation Criteria

[0236] ◎: The protrusion amount and the climbing amount of the resin from the wafer edge are less than 10 μm

[0237] ×: The protrusion amount and the climbing amount of the resin from the wafer edge are 10 μm or more

[0238] (9) Defect

[0239] The samples used in the above workability evaluation were observed to confirm the defect amount, and the evaluation was carried out based on the following evaluation criteria.

[0240] [Evaluation Criteria]

[0241] ◎: The defect amount of the resin from the wafer edge into the resin is less than 10 μm

[0242] ×: The defect amount of the resin from the wafer edge into the resin is 10 μm or more

[0243] (10) Reliability

[0244] After subjecting the sealed samples prepared in the above appearance evaluation to 3 cycles of 260 °C × 1 minute, SAT was used to confirm whether there was peeling between the sealing sheet and the wafer. Then, the reliability was evaluated based on the following evaluation criteria.

[0245] [Evaluation Criteria]

[0246] ◎: Among the samples input at n9, the number of samples that became black shadows in SAT was 0 / 9

[0247] 〇: Among the samples input at n9, the number of samples that became black shadows in SAT was 1 / 9 or more and 3 / 9 or less

[0248] ×: Among the samples input at n9, the number of samples that became black shadows in SAT was 4 / 9 or more

[0249]

[0250] As shown in Table 1, the sealing sheet of the example was evaluated as having antireflectivity, excellent workability, no defects generated, and excellent reliability. In contrast, when a non-colored adhesive layer was used instead of the non-colored adhesive agent layer (Comparative Example 1), it was evaluated as having poor workability, defects generated, voids generated during sealing, and poor reliability.

[0251] Hereinafter, variations of the present invention will be described.

[0252] [Supplementary Note 1] A sheet for sealing an optoelectronic semiconductor element, which is a sheet for sealing one or more optoelectronic semiconductor elements disposed on a substrate, wherein the sheet has a sealing resin layer, the sealing resin layer includes at least a colored layer and a non-colored adhesive agent layer having thermosetting properties, the colored layer contains a colorant, the elastic modulus G' of the non-colored adhesive agent layer before curing at 130 °C is 0.5 kPa to 10 kPa, and the non-colored adhesive agent layer is a layer that contacts the optoelectronic semiconductor element when sealing the optoelectronic semiconductor element.

[0253] [Supplementary Note 2] The sheet for sealing an optoelectronic semiconductor element according to Supplementary Note 1, wherein the thickness of the non-colored adhesive agent layer is 5 μm to 75 μm.

[0254] [Supplementary Note 3] The sheet for sealing an optoelectronic semiconductor element according to Supplementary Note 1 or 2, wherein the elastic modulus E' of the non-colored adhesive agent layer before curing at room temperature is 500 MPa to 4000 MPa.

[0255] [Supplementary Note 4] The sheet for sealing an optoelectronic semiconductor element according to any one of Supplementary Notes 1 to 3, wherein the elastic modulus E' of the non-colored adhesive agent layer after curing at room temperature is 500 MPa to 4000 MPa.

[0256] [Supplementary Note 5] The sheet for sealing an optoelectronic semiconductor element according to any one of Supplementary Notes 1 to 4, wherein the light transmittance of the non-colored adhesive agent layer after curing at a wavelength of 600 nm is greater than 80%.

[0257] [Supplementary Note 6] The sheet for sealing an optoelectronic semiconductor element according to any one of Supplementary Notes 1 to 5, wherein, in the state after sealing the optoelectronic semiconductor element, the distance from the optoelectronic semiconductor element to the non-colored adhesive agent layer is 0 μm to 20 μm.

[0258] [Supplementary Note 7] The sheet for sealing an optoelectronic semiconductor element according to any one of Supplementary Notes 1 to 6, wherein the colored layer is a colored adhesive agent layer having thermosetting properties, and the light transmittance of the colored adhesive agent layer after curing at a wavelength of 600 nm is 0% to 80%.

[0259] [Supplementary Note 8] The sheet for sealing an optical semiconductor element according to any one of Supplementary Notes 1 to 7, wherein the colored layer is a thermosetting colored adhesive layer, and the ratio of the room temperature elastic modulus E' after curing of the colored adhesive layer to the room temperature elastic modulus E' before curing [room temperature elastic modulus E' after curing / room temperature elastic modulus E' before curing] is 0.6 to 2.0.

[0260] [Supplementary Note 9] The sheet for sealing an optical semiconductor element according to any one of Supplementary Notes 1 to 8, wherein a layer having antiglare property and / or antireflection property is provided on the surface of the sealing resin layer on the side opposite to the side in contact with the optical semiconductor element.

[0261] [Supplementary Note 10] An optical semiconductor device, wherein the optical semiconductor device includes: a substrate; an optical semiconductor element disposed on the substrate; and the sheet for sealing an optical semiconductor element according to any one of Supplementary Notes 1 to 9 or a cured product thereof for sealing the optical semiconductor element.

Claims

1. A sheet for sealing an opto-semiconductor device, the sheet for sealing an opto-semiconductor device being a sheet for sealing one or more opto-semiconductor devices disposed on a substrate, wherein, the sheet has a sealing resin layer, the sealing resin layer including at least a colored layer and a non-colored adhesive layer having thermosetting properties, the colored layer contains a colorant, the elastic modulus G' at 130 °C before curing of the non-colored adhesive layer is 0.5 kPa to 10 kPa, and the non-colored adhesive layer is a layer that contacts the opto-semiconductor device when sealing the opto-semiconductor device.

2. The sheet for sealing an opto-semiconductor device according to claim 1, wherein, The thickness of the non-colored adhesive layer is 5 μm to 75 μm.

3. The sheet for sealing an opto-semiconductor element according to claim 1 or 2, wherein, The elastic modulus E' at normal temperature before curing of the non-colored adhesive layer is 500 MPa to 4000 MPa.

4. The sheet for sealing an opto-semiconductor element according to claim 1 or 2, wherein, The elastic modulus E' at normal temperature after curing of the non-colored adhesive layer is 500 MPa to 4000 MPa.

5. The sheet for sealing an opto-semiconductor element according to claim 1 or 2, wherein, The light transmittance at a wavelength of 600 nm after curing of the non-colored adhesive layer is greater than 80%.

6. The sheet for sealing an opto-semiconductor element according to claim 1 or 2, wherein, In a state where the opto-semiconductor device is sealed, the distance from the opto-semiconductor device to the non-colored adhesive layer is 0 μm to 20 μm.

7. The sheet for sealing an optical semiconductor element according to claim 1 or 2, wherein, The colored layer is a colored adhesive layer having thermosetting properties, The light transmittance at a wavelength of 600 nm after curing of the colored adhesive layer is 0% to 80%.

8. The sheet for sealing an opto-semiconductor device according to claim 1 or 2, wherein, the colored layer is a colored adhesive layer having thermosetting properties, the ratio [elastic modulus E' at normal temperature after curing / elastic modulus E' at normal temperature before curing] of the elastic modulus E' at normal temperature after curing of the colored adhesive layer to the elastic modulus E' at normal temperature before curing is 0.6 to 2.

0.

9. The sheet for sealing an opto-semiconductor element according to claim 1 or 2, wherein, On the surface of the sealing resin layer on the side opposite to the side in contact with the opto-semiconductor device, a layer having antiglare properties and / or antireflection properties is provided.

10. A photo-semiconductor device, wherein, The opto-semiconductor device includes: a substrate; an opto-semiconductor device disposed on the substrate; and the sheet for sealing an opto-semiconductor device according to any one of claims 1 to 9 or a cured product thereof for sealing the opto-semiconductor device.

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