Adhesive film and method for manufacturing electronic device

Abstract

An adhesive film (50) containing a heat-resistant pigment, the heat-resistant pigment having an absorbance of 0.50 or less at the maximum absorption wavelength λmax.

Description

Method for manufacturing adhesive film and electronic device

[0001] The present invention relates to a method for manufacturing an adhesive film and an electronic device.

[0002] Fan-out packaging is known as a technology that can reduce the size and weight of electronic devices (e.g., semiconductor devices). One method for fabricating a fan-out package, called an embedded wafer level ball grid array (eWLB), involves temporarily fixing a plurality of electronic components, such as semiconductor chips, spaced apart on an adhesive film attached to a support substrate, and then encapsulating the plurality of electronic components together with an encapsulant. Here, the adhesive film must be adhered to the electronic components and the support substrate during the encapsulation process, and must be removed from the encapsulated electronic components together with the support substrate after encapsulation.

[0003] Techniques relating to a manufacturing method for such a fan-out type package include, for example, the technique described in Patent Document 1 (Japanese Patent Laid-Open No. 2011-134811).

[0004] Patent Document 1 describes a heat-resistant adhesive sheet for semiconductor device manufacturing that is used by adhering when resin-encapsulating a substrateless semiconductor chip, with the aim of solving the problem of the chip not being held in place due to pressure during resin encapsulation and shifting from its designated position, or the problem of the package being damaged when the heat-resistant adhesive sheet for semiconductor device manufacturing is peeled off due to the hardening of the encapsulant or heat causing the encapsulant to become strongly adhesive to the chip surface, the heat-resistant adhesive sheet having a base layer and an adhesive layer, the adhesive layer having an adhesive strength to SUS304 after lamination of 0.5 N / 20 mm or more, and hardening due to stimuli received up to the time the resin encapsulation process is completed, so that the peel strength to the package is 2.0 N / 20 mm or less.

[0005] JP 2011-134811 A

[0006] The present inventors have investigated the addition of a dye to an adhesive film to color it in order to improve the distinguishability of the adhesive film in the manufacturing process of an electronic device. The inventors' investigations have revealed that, when an adhesive film containing a dye is heated in the manufacturing process of an electronic device, contamination of a part of the equipment used in manufacturing the electronic device may occur. The present invention provides an adhesive film that can suppress equipment contamination.

[0007] The present inventors have conducted extensive research to achieve the above object, and as a result have found that when an adhesive film contains a heat-resistant dye whose absorbance measured under specific conditions is in a specific range, contamination of the device can be suppressed, and have completed the present invention.

[0008] According to the present invention, the following methods for producing a pressure-sensitive adhesive film and an electronic device are provided.

[0009] [1] An adhesive film containing a heat-resistant dye, wherein the maximum absorption wavelength λ of the heat-resistant dye is measured by the following method: ｍａｘ An adhesive film having an absorbance of 0.50 or less at 1000 kJ / cm². (Method) 0.5 g of the heat-resistant dye is placed in a 5 cm diameter beaker, and a 5 x 5 cm glass plate is placed on top to cover the beaker. The beaker covered with the glass plate is then heated on a hot plate at 250°C for 8 hours. After heating, the glass plate is removed, and the UV-visible absorption spectrum of the glass plate is measured in the wavelength range of 360 to 800 nm using a UV-visible spectrophotometer, and the maximum absorption wavelength λ ｍａｘ [2] The absorbance is calculated at the maximum absorption wavelength λ in the wavelength range of 360 to 800 nm. ｍａｘThe pressure-sensitive adhesive film according to [1] above, wherein the average particle diameter is 360 nm or more and 600 nm or less. [3] The pressure-sensitive adhesive film according to [1] or [2] above, wherein the heat-resistant colorant comprises a heat-resistant pigment. [4] The pressure-sensitive adhesive film according to [3] above, wherein the heat-resistant pigment comprises one or more selected from the group consisting of phthalocyanine colorants, quinacridone colorants, and isoindolinone colorants. [5] The pressure-sensitive adhesive film according to any of [1] to [4] above, wherein the heat-resistant colorant has a molecular weight of 350 or more. [6] The pressure-sensitive adhesive film according to any of [1] to [5] above, wherein the heat-resistant colorant has a melting point of 200°C or more. [7] The pressure-sensitive adhesive film according to any of [1] to [6] above, wherein the content of the heat-resistant colorant is 0.001% by mass or more and 10.0% by mass or less, when the entire pressure-sensitive adhesive film is taken as 100% by mass. [8] The pressure-sensitive adhesive film according to any one of the above [1] to [7], comprising an adhesive resin layer (A) and a base layer, wherein at least one layer selected from the group consisting of the adhesive resin layer (A) and the base layer contains the heat-resistant dye. [9] The pressure-sensitive adhesive film according to any one of the above [1] to [7], comprising an adhesive resin layer (A), a base layer, and an adhesive resin layer (B) in this order, wherein at least one layer selected from the group consisting of the adhesive resin layer (A), the base layer, and the adhesive resin layer (B) contains the heat-resistant dye.

[10] The pressure-sensitive adhesive film according to any one of [1] to [7] above, comprising an adhesive resin layer (A), a base layer, and an adhesive resin layer (B) in this order, and further comprising an intermediate layer (C) between the adhesive resin layer (A) and the base layer and between at least one layer selected from the group consisting of the base layer and the adhesive resin layer (B), wherein at least one layer selected from the group consisting of the adhesive resin layer (A), the intermediate layer (C), the base layer, and the adhesive resin layer (B) contains the heat-resistant dye.

[11] The pressure-sensitive adhesive film according to [9] or

[10] above, wherein the adhesive resin layer (B) is a layer whose adhesive strength decreases by heat treatment.

[12] The pressure-sensitive adhesive film according to any one of [9] to

[11] above, wherein the adhesive resin layer (B) contains a thermally expandable adhesive.

[13] The pressure-sensitive adhesive film according to

[12] above, wherein the thermally expandable pressure-sensitive adhesive is a pressure-sensitive adhesive whose adhesive strength decreases or is lost when heated at a temperature exceeding 150°C.

[14] The pressure-sensitive adhesive film according to any one of [9] to

[13] above, wherein the pressure-sensitive adhesive resin layer (B) contains one or more selected from the group consisting of (meth)acrylic pressure-sensitive adhesive resins, silicone pressure-sensitive adhesive resins, urethane pressure-sensitive adhesive resins, olefin pressure-sensitive adhesive resins, and styrene pressure-sensitive adhesive resins.

[15] The pressure-sensitive adhesive film according to any one of [9] to

[14] above, wherein the thickness of the pressure-sensitive adhesive resin layer (B) is 3 μm or more and 300 μm or less.

[16] The pressure-sensitive adhesive film according to any one of [9] to

[15] above, wherein at least one layer selected from the group consisting of the pressure-sensitive adhesive resin layer (B) and the intermediate layer (C) contains the heat-resistant dye.

[17] The pressure-sensitive adhesive film according to

[10] or

[16] above, wherein the intermediate layer (C) comprises one or more selected from the group consisting of polyolefin resins, ethylene-carboxylic anhydride copolymers, ethylene-epoxy copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-ethylenically unsaturated acid copolymers, ethylene-vinyl ester copolymers, polystyrene resins, and (meth)acrylic resins.

[18] The pressure-sensitive adhesive film according to

[10] ,

[16] , or

[17] above, wherein the thickness of the intermediate layer (C) is 1 μm or more and 500 μm or less.

[19] The pressure-sensitive adhesive film according to any one of [8] to

[18] above, wherein the pressure-sensitive adhesive resin layer (A) comprises one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, and styrene adhesive resins.

[20] The pressure-sensitive adhesive film according to any one of the above [8] to

[19] , wherein the total content of the gas-generating component and heat-expandable microspheres in the pressure-sensitive adhesive resin layer (A) is 0.1 mass% or less, when the entire pressure-sensitive adhesive resin layer (A) is taken as 100 mass%.

[21] The pressure-sensitive adhesive film according to any one of the above [8] to

[20] , wherein the thickness of the pressure-sensitive adhesive resin layer (A) is 1 μm or more and 100 μm or less.

[22] The pressure-sensitive adhesive film according to any one of [1] to

[21] above, which is capable of temporarily fixing an electronic component when sealing the electronic component with a sealing material.

[23] A method for manufacturing an electronic device, comprising: (a) preparing a structure including the pressure-sensitive adhesive film according to any one of [1] to

[22] above and an electronic component attached to the pressure-sensitive adhesive film; and (b) sealing the electronic component with a sealing material.

[24] The method for manufacturing an electronic device according to

[23] above, wherein the sealing material comprises an epoxy resin-based sealing material.

[25] The method for manufacturing an electronic device according to

[23] or

[24] above, wherein the electronic device comprises a fan-out package.

[0010] According to the present invention, it is possible to provide an adhesive film that can suppress contamination of equipment.

[0011] Fig. 1 is a cross-sectional view schematically showing an example of the structure of an adhesive film according to an embodiment of the present invention. Fig. 2 is a cross-sectional view schematically showing an example of the structure of an adhesive film according to an embodiment of the present invention. Fig. 3 is a cross-sectional view schematically showing an example of the structure of an adhesive film according to an embodiment of the present invention. Fig. 4 is a cross-sectional view schematically showing an example of a method for manufacturing an electronic device according to an embodiment of the present invention.

[0012] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by common reference numerals, and descriptions thereof will be omitted where appropriate. Furthermore, the drawings are schematic diagrams and do not necessarily correspond to actual dimensional ratios. In the specification, the expression "A to B" regarding a numerical range means A or more and B or less, unless otherwise specified. For example, 1 to 5% means 1% or more and 5% or less. In the specification, "(meth)acrylic" means acrylic, methacrylic, or both acrylic and methacrylic.

[0013] <Adhesive Film> The adhesive film 50 of this embodiment will be described below. The adhesive film 50 of this embodiment is an adhesive film containing a heat-resistant dye, and is a film having a maximum absorption wavelength λ of the heat-resistant dye measured by the following method: ｍａｘ The absorbance at 1000 nm is 0.50 or less.

[0014] (Method) 0.5 g of the heat-resistant dye was placed in a 5 cm diameter beaker, and a 5 x 5 cm glass plate was placed on top to cover it. The beaker with the glass plate lid was then heated on a hot plate at 250°C for 8 hours. After heating, the glass plate was removed, and the UV-visible absorption spectrum of the glass plate was measured in the wavelength range of 360 to 800 nm using a UV-visible spectrophotometer. The maximum absorption wavelength λ ｍａｘ The absorbance at

[0015] The present inventors investigated the addition of a dye to a pressure-sensitive adhesive film to color it in order to improve its distinguishability. The inventors' investigations revealed that heating a pressure-sensitive adhesive film during the manufacturing process of an electronic device can sometimes cause contamination of part of the equipment used to manufacture the electronic device. The present invention can suppress equipment contamination by using a heat-resistant dye having a specific absorbance in the pressure-sensitive adhesive film. While the reason for this is unclear, it is believed that the heat-resistant dye having a specific absorbance is highly stable, and therefore can suppress the phenomenon of the dye in the pressure-sensitive adhesive film sublimating due to heating during the manufacturing process of the electronic device, thereby suppressing equipment contamination.

[0016] The absorbance of the heat-resistant dye in the pressure-sensitive adhesive film 50 of this embodiment is preferably 0.45 or less, more preferably 0.40 or less, even more preferably 0.35 or less, even more preferably 0.30 or less, even more preferably 0.25 or less, even more preferably 0.20 or less, and even more preferably 0.15 or less, from the viewpoint of further suppressing equipment contamination. The lower limit of the absorbance of the heat-resistant dye is not particularly limited, but may be, for example, 0.00 or more, 0.01 or more, or 0.03 or more. Furthermore, the absorbance of the heat-resistant dye in the pressure-sensitive adhesive film 50 of this embodiment is preferably 0.00 or more and 0.45 or less, more preferably 0.00 or more and 0.40 or less, even more preferably 0.00 or more and 0.35 or less, even more preferably 0.00 or more and 0.30 or less, even more preferably 0.00 or more and 0.25 or less, even more preferably 0.01 or more and 0.20 or less, and even more preferably 0.03 or more and 0.15 or less, from the viewpoint of further suppressing equipment contamination.

[0017] The maximum absorption wavelength λ of the heat-resistant dye in the adhesive film 50 of this embodiment in the wavelength range of 360 to 800 nm ｍａｘ From the viewpoint of further suppressing device contamination while improving the color development of the adhesive film 50, the thickness is preferably 360 nm or more and 600 nm or less, more preferably 360 nm or more and 500 nm or less, and even more preferably 360 nm or more and 400 nm or less.

[0018] The heat-resistant dye in the adhesive film 50 of this embodiment will be described in detail below.

[0019] The heat-resistant dye of this embodiment preferably contains a heat-resistant pigment from the viewpoint of further improving the balance of performance between resistance to color unevenness and stain resistance of the pressure-sensitive adhesive film 50. It is thought that the heat-resistant dye of this embodiment containing a particularly stable heat-resistant pigment can further suppress the phenomenon of sublimation of the dye in the pressure-sensitive adhesive film due to heating during the manufacture of electronic devices.

[0020] From the viewpoint of further improving the performance balance between the color unevenness resistance and contamination resistance of the adhesive film, the heat-resistant pigment of this embodiment preferably contains one or more selected from the group consisting of phthalocyanine-based dyes, quinacridone-based dyes, and isoindolinone-based dyes, and more preferably contains a phthalocyanine-based dye.

[0021] Specific examples of the phthalocyanine dye of this embodiment include C.I. Pigment Green 7, C.I. Pigment Green 36, C.I. Pigment Green 58, C.I. Pigment Blue 15, C.I. Pigment Blue 15:1, C.I. Pigment Blue 15:3, and C.I. Pigment Blue 15:6.

[0022] Specific examples of the quinacridone dye of this embodiment include C.I. Pigment Red 19, C.I. Pigment Red 122, and C.I. Pigment Violet 19.

[0023] Specific examples of the isoindolinone dye of this embodiment include C.I. Pigment Yellow 12 and C.I. Pigment Yellow 110.

[0024] From the viewpoint of further improving the performance balance between color unevenness resistance and contamination resistance of the PSA film, the molecular weight of the heat-stable dye of this embodiment is preferably 350 or more, more preferably 360 or more, even more preferably 370 or more, even more preferably 380 or more, even more preferably 390 or more, even more preferably 400 or more, even more preferably 410 or more, even more preferably 420 or more, even more preferably 430 or more, even more preferably 440 or more, and even more preferably 450 or more. The upper limit of the molecular weight of the heat-stable dye of this embodiment is not particularly limited, and may be, for example, 5000 or less, 4000 or less, 3000 or less, 2000 or less, or 1500 or less. That is, from the viewpoint of further improving the performance balance between color unevenness resistance and contamination resistance of the adhesive film, the molecular weight of the heat-resistant dye of this embodiment is preferably 350 or more and 5,000 or less, more preferably 360 or more and 5,000 or less, even more preferably 370 or more and 5,000 or less, even more preferably 380 or more and 4,000 or less, even more preferably 390 or more and 4,000 or less, even more preferably 400 or more and 3,000 or less, even more preferably 410 or more and 3,000 or less, even more preferably 420 or more and 2,000 or less, even more preferably 430 or more and 2,000 or less, even more preferably 440 or more and 1,500 or less, and even more preferably 450 or more and 1,500 or less.

[0025] From the viewpoint of further improving the performance balance between color unevenness resistance and contamination resistance of the PSA film, the melting point of the heat-resistant dye of this embodiment is preferably 200° C. or higher, more preferably 210° C. or higher, even more preferably 220° C. or higher, even more preferably 230° C. or higher, even more preferably 240° C. or higher, even more preferably 250° C. or higher, even more preferably 260° C. or higher, even more preferably 270° C. or higher, even more preferably 280° C. or higher, even more preferably 290° C. or higher, and even more preferably 300° C. or higher. The upper limit of the melting point of the heat-resistant dye of this embodiment is not particularly limited, and may be, for example, 1000° C. or lower, 900° C. or lower, 800° C. or lower, or 700° C. or lower. That is, from the viewpoint of further improving the performance balance between the color unevenness resistance and contamination resistance of the adhesive film, the melting point of the heat-resistant dye of this embodiment is preferably 200°C or higher and 1000°C or lower, more preferably 210°C or higher and 1000°C or lower, even more preferably 220°C or higher and 1000°C or lower, even more preferably 230°C or higher and 1000°C or lower, even more preferably 240°C or higher and 900°C or lower, even more preferably 250°C or higher and 900°C or lower, even more preferably 260°C or higher and 900°C or lower, even more preferably 270°C or higher and 800°C or lower, even more preferably 280°C or higher and 800°C or lower, even more preferably 290°C or higher and 700°C or lower, and even more preferably 300°C or higher and 700°C or lower.

[0026] The heat-resistant dye of the present embodiment is preferably a dye dispersion liquid dispersed in a solvent, which preferably contains one or more solvents selected from the group consisting of ethyl acetate, methyl acetate, acetone, methyl ethyl ketone (MEK), benzene, toluene, ethylbenzene, heptane, hexane, cyclohexane, methanol, ethanol, isopropanol, and butanol, from the viewpoint of further improving the balance between the color unevenness resistance and the stain resistance of the PSA film, and more preferably contains ethyl acetate.

[0027] The method for producing the dye dispersion of this embodiment preferably includes a step of dispersing the heat-resistant dye of this embodiment in the solvent using a homogenizer, from the viewpoint of further improving the balance between the color unevenness resistance and contamination resistance of the pressure-sensitive adhesive film. It is believed that the homogenizer has strong dispersing power and can thoroughly disperse the heat-resistant dye of this embodiment in the solvent. When such a well-dispersed dye dispersion is used to produce the pressure-sensitive adhesive film 50, the heat-resistant dye does not aggregate inside the pressure-sensitive adhesive film 50, and as a result, it is believed that the color unevenness resistance of the pressure-sensitive adhesive film can be improved.

[0028] In the method for producing the pigment dispersion liquid of this embodiment, the time for dispersing the heat-resistant pigment of this embodiment in the above-mentioned solvent is preferably 1 minute or more and 60 minutes or less, more preferably 3 minutes or more and 50 minutes or less, even more preferably 5 minutes or more and 40 minutes or less, even more preferably 8 minutes or more and 30 minutes or less, and even more preferably 10 minutes or more and 20 minutes or less, from the viewpoint of further improving the production efficiency of the pigment dispersion liquid and the performance balance between color unevenness resistance and contamination resistance of the adhesive film.

[0029] In the method for producing the dye dispersion liquid of this embodiment, the rotation speed of the homogenizer when dispersing the heat-resistant dye of this embodiment in the above-mentioned solvent is preferably 1,000 rpm or more and 20,000 rpm or less, more preferably 3,000 rpm or more and 15,000 rpm or less, and even more preferably 5,000 rpm or more and 10,000 rpm or less, from the viewpoint of further improving the production efficiency of the dye dispersion liquid and the performance balance between color unevenness resistance and contamination resistance of the adhesive film.

[0030] In order to further improve the performance balance between the color unevenness resistance and contamination resistance of the adhesive film, the content of the heat-resistant dye in the adhesive film 50 of this embodiment is preferably 0.001% by mass or more and 10.0% by mass or less, more preferably 0.002% by mass or more and 9.0% by mass or less, and even more preferably 0.003% by mass or more and 8.0% by mass or less, when the entire adhesive film 50 is taken as 100% by mass.

[0031] The total thickness of the adhesive film 50 of this embodiment is preferably 10 μm or more and 1500 μm or less, more preferably 20 μm or more and 1000 μm or less, from the viewpoint of the balance between mechanical properties and handling properties.

[0032] Examples of the electronic component 70 include semiconductor chips such as ICs, LSIs, discrete devices, light-emitting diodes, and light-receiving elements, as well as semiconductor panels and semiconductor packages. Examples of the semiconductor substrate include silicon substrates, sapphire substrates, germanium substrates, germanium-arsenic substrates, gallium-phosphorus substrates, gallium-arsenic-aluminum substrates, gallium-arsenic substrates, and lithium tantalate substrates.

[0033] The adhesive film 50 of this embodiment is preferably capable of temporarily fixing the electronic component 70 when sealing the electronic component 70 with a sealing material. In this case, the electronic component 70 preferably has an uneven structure.

[0034] Here, the uneven structure of the electronic component preferably includes a bump electrode. When the uneven structure of the electronic component includes a bump electrode, when the height of the bump electrode is H [μm] and the thickness of the unevenness-absorbing resin layer (C) is d [μm], H / d is preferably 1 or less, more preferably 0.85 or less, and even more preferably 0.7 or less. When H / d is equal to or less than the above upper limit, the thickness of the pressure-sensitive adhesive film 50 can be made thinner while improving the unevenness absorbency. The lower limit of H / d is not particularly limited, but is, for example, 0.01 or more. The height of the bump electrode is generally 2 μm or more and 600 μm or less.

[0035] In one aspect of the adhesive film 50 of the present embodiment, as shown in FIG. 1, from the viewpoint of being able to suppress misalignment of the electronic component 70, the adhesive film 50 of the present embodiment preferably comprises an adhesive resin layer (A) and a base layer, and at least one layer selected from the group consisting of the adhesive resin layer (A) and the base layer contains the heat-resistant dye.

[0036] In addition, in one aspect of the adhesive film 50 of the present embodiment, as shown in FIG. 2, from the viewpoint of being able to suppress misalignment of the electronic component 70, the adhesive film 50 of the present embodiment preferably comprises an adhesive resin layer (A), a base layer, and an adhesive resin layer (B) in this order, and at least one layer selected from the group consisting of the adhesive resin layer (A), the base layer, and the adhesive resin layer (B) contains the heat-resistant dye.

[0037] Moreover, in one aspect of the adhesive film 50 of the present embodiment, as shown in FIG. 3 , from the viewpoint of being able to suppress misalignment of the electronic component 70 and to improve the performance balance of the conformability and adhesion of the adhesive film 50 to the electronic component and the supporting substrate, the adhesive film 50 of the present embodiment preferably comprises an adhesive resin layer (A), a base layer, and an adhesive resin layer (B) in this order, and further comprises an intermediate layer (C) between at least one layer selected from the group consisting of the adhesive resin layer (A) and the base layer, and between the base layer and the adhesive resin layer (B), and at least one layer selected from the group consisting of the adhesive resin layer (A), the intermediate layer (C), the base layer, and the adhesive resin layer (B) contains the heat-resistant dye.

[0038] When at least one layer selected from the group consisting of the adhesive resin layer (A), the intermediate layer (C), the base layer, and the adhesive resin layer (B) of this embodiment contains a heat-resistant dye, the content of the heat-resistant dye contained in each layer, when the entire layer is taken as 100 mass%, is preferably 0.001 mass% or more and 10.0 mass% or less, more preferably 0.010 mass% or more and 9.0 mass% or less, even more preferably 0.020 mass% or more and 8.0 mass% or less, even more preferably 0.030 mass% or more and 7.0 mass% or less, even more preferably 0.050 mass% or more and 6.0 mass% or less, even more preferably 0.070 mass% or more and 5.0 mass% or less, and even more preferably 0.080 mass% or more and 4.5 mass% or less, from the viewpoint of further suppressing equipment contamination.

[0039] Next, each layer constituting the adhesive film 50 of this embodiment will be described.

[0040] [Base layer] The base layer 10 is a layer provided for the purpose of improving the properties such as handleability, mechanical properties, and heat resistance of the pressure-sensitive adhesive film 50. The base layer 10 is not particularly limited, but examples thereof include a resin film.

[0041] The substrate layer 10 preferably contains a thermoplastic resin. The thermoplastic resin constituting the substrate layer 10 of this embodiment preferably contains one or more selected from polyolefins such as polyethylene, polypropylene, poly(4-methyl-1-pentene), and poly(1-butene); polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate; polyamides such as nylon-6, nylon-66, and polymethaxylene adipamide; polyacrylate; polymethacrylate; polyvinyl chloride; polyvinylidene chloride; polyimide; polyetherimide; ethylene-vinyl acetate copolymer; polyacrylonitrile; polycarbonate; polystyrene; ionomer; polysulfone; polyethersulfone; polyphenylene ether, and the like. Among these, from the viewpoint of an excellent balance of transparency, mechanical strength, price, and the like, the substrate layer 10 preferably contains one or more selected from polypropylene, polyethylene terephthalate, polyethylene naphthalate, polyamide, and polyimide, and more preferably contains one or more selected from polyethylene terephthalate and polyethylene naphthalate.

[0042] The base layer 10 may be a single layer or two or more layers. The resin film used to form the base layer 10 may be a stretched film or a uniaxially or biaxially stretched film, but from the viewpoint of improving the mechanical strength of the base layer 10, a uniaxially or biaxially stretched film is preferred.

[0043] From the viewpoint of obtaining good film properties, the thickness of the substrate layer 10 is preferably 10 μm or more and 1000 μm or less, more preferably 20 μm or more and 500 μm or less, and even more preferably 30 μm or more and 100 μm or less. The substrate layer 10 may be subjected to a surface treatment to improve adhesion to other layers. Specifically, corona treatment, plasma treatment, undercoat treatment, primer coating treatment, etc. may be performed.

[0044] [Adhesive Resin Layer (A)] In one aspect of the adhesive film 50 of the present embodiment, from the viewpoint of suppressing misalignment of the electronic component 70, an adhesive resin layer (A) is preferably provided on one surface of the base layer 10. The adhesive resin layer (A) is a layer that comes into contact with the surface of the electronic component to temporarily fix the electronic component when, for example, sealing the electronic component with a sealing material in the manufacturing process of the electronic device.

[0045] The adhesive resin layer (A) preferably contains an adhesive resin (Aa). The adhesive resin (Aa) preferably contains one or more selected from the group consisting of (meth)acrylic adhesive resin (a), silicone adhesive resin, urethane adhesive resin, olefin adhesive resin, and styrene adhesive resin. Among these, the adhesive resin (Aa) preferably contains a (meth)acrylic adhesive resin (a) from the viewpoint of suppressing misalignment of the electronic component 70 and improving the performance balance of adhesive strength.

[0046] The adhesive resin layer (A) may be a radiation-crosslinkable adhesive resin layer whose adhesive strength can be reduced by radiation. When the radiation-crosslinkable adhesive resin layer is irradiated with radiation, crosslinking occurs, significantly reducing the adhesive strength, making it easier to peel the adhesive film 50 from the electronic component. Examples of radiation include ultraviolet light, electron beams, and infrared light. The radiation-crosslinkable adhesive resin layer preferably includes an ultraviolet-crosslinkable adhesive resin layer.

[0047] The (meth)acrylic adhesive resin (a) used in the adhesive resin layer (A) of this embodiment preferably comprises a copolymer containing (meth)acrylic acid alkyl ester monomer units (a1) and monomer units (a2) having a functional group capable of reacting with a crosslinking agent. In this embodiment, the (meth)acrylic acid alkyl ester refers to an acrylic acid alkyl ester, a methacrylic acid alkyl ester, or a mixture thereof.

[0048] The (meth)acrylic adhesive resin (a) of the present embodiment can be obtained, for example, by copolymerizing a monomer mixture containing a (meth)acrylic acid alkyl ester monomer and a monomer having a functional group capable of reacting with a crosslinking agent.

[0049] The (meth)acrylic acid alkyl ester monomer of this embodiment preferably includes a (meth)acrylic acid alkyl ester having an alkyl group having about 1 to 12 carbon atoms, and more preferably includes a (meth)acrylic acid alkyl ester having an alkyl group having 1 to 8 carbon atoms. The (meth)acrylic acid alkyl ester having an alkyl group having about 1 to 12 carbon atoms preferably includes one or more selected from the group consisting of methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, and 2-ethylhexyl methacrylate. In the (meth)acrylic adhesive resin (a) of this embodiment, the content of the (meth)acrylic acid alkyl ester monomer unit (a1) is preferably 10% by mass or more and 98.9% by mass or less, more preferably 50% by mass or more and 97% by mass or less, and even more preferably 85% by mass or more and 95% by mass or less, when the total of all monomer units in the (meth)acrylic adhesive resin (a) is taken as 100% by mass.

[0050] Preferred examples of the monomer having a functional group reactive with the crosslinking agent of this embodiment include acrylic acid, methacrylic acid, itaconic acid, mesaconic acid, citraconic acid, fumaric acid, maleic acid, monoalkyl itaconic acid esters, monoalkyl mesaconic acid esters, monoalkyl citraconic acid esters, monoalkyl fumaric acid esters, monoalkyl maleic acid esters, glycidyl acrylate, glycidyl methacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, methacrylamide, tert-butylaminoethyl acrylate, tert-butylaminoethyl methacrylate, etc. More preferred examples of the monomer having a functional group reactive with the crosslinking agent of this embodiment include one or more selected from the group consisting of acrylic acid, methacrylic acid, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, acrylamide, and methacrylamide. In the (meth)acrylic adhesive resin (a) of the present embodiment, the content of the monomer unit (a2) having a functional group capable of reacting with a crosslinking agent is preferably 1% by mass or more and 40% by mass or less, more preferably 1% by mass or more and 20% by mass or less, and even more preferably 1% by mass or more and 10% by mass or less, when the total of all monomer units in the (meth)acrylic adhesive resin (a) is 100% by mass.

[0051] The (meth)acrylic adhesive resin (a) of this embodiment may further contain, in addition to the (meth)acrylic acid alkyl ester monomer unit (a1) and the monomer unit (a2) having a functional group reactive with a crosslinking agent, a bifunctional monomer unit (a3) ​​or a specific comonomer unit having surfactant properties (hereinafter referred to as a polymerizable surfactant). The polymerizable surfactant has the property of copolymerizing with the (meth)acrylic acid alkyl ester monomer, the monomer having a functional group reactive with a crosslinking agent, and the bifunctional monomer, and also acts as an emulsifier when emulsion polymerization is performed.

[0052] The bifunctional monomer of the present embodiment preferably includes one or more monomers selected from the group consisting of allyl methacrylate, allyl acrylate, divinylbenzene, vinyl methacrylate, vinyl acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tetraethylene glycol di(meth)acrylate, monomers having diacrylate or dimethacrylate at both ends and a propylene glycol main chain structure (e.g., manufactured by NOF Corporation, trade names: PDP-200, PDP-400, ADP-200, ADP-400), tetramethylene glycol monomers (e.g., manufactured by NOF Corporation, trade names: ADT-250, ADT-850), and mixtures thereof (e.g., manufactured by NOF Corporation, trade names: ADET-1800, ADPT-4000).

[0053] In the (meth)acrylic adhesive resin (a) of the present embodiment, the content of the bifunctional monomer unit (a3) ​​is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, even more preferably 0.1% by mass or more and 15% by mass or less, and still more preferably 0.1% by mass or more and 5% by mass or less, when the total of all monomer units in the (meth)acrylic adhesive resin (a) is 100% by mass.

[0054] The polymerizable surfactant of this embodiment preferably includes one or more surfactants selected from the group consisting of polyoxyethylene nonylphenyl ether having a polymerizable 1-propenyl group introduced into the benzene ring (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: AQUALON RN-10, RN-20, RN-30, RN-50, etc.), polyoxyethylene nonylphenyl ether sulfate ammonium salt having a polymerizable 1-propenyl group introduced into the benzene ring (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.; trade names: AQUALON HS-10, HS-20, HS-1025, etc.), and sulfosuccinic acid diesters having a polymerizable double bond in the molecule (manufactured by Kao Corporation; trade names: Latemul S-120A, S-180A, etc.). In the (meth)acrylic adhesive resin (a) of the present embodiment, the content of the polymerizable surfactant is preferably 0.1% by mass or more and 30% by mass or less, more preferably 0.1% by mass or more and 20% by mass or less, even more preferably 0.1% by mass or more and 15% by mass or less, and still more preferably 0.1% by mass or more and 5% by mass or less, when the sum of all monomer units in the (meth)acrylic adhesive resin (a) is 100% by mass.

[0055] The (meth)acrylic adhesive resin (a) of the present embodiment may further contain, if necessary, a monomer unit formed from a monomer having a polymerizable double bond, such as vinyl acetate, acrylonitrile, or styrene.

[0056] The polymerization reaction mechanism of the (meth)acrylic adhesive resin (a) of this embodiment may be radical polymerization, anionic polymerization, cationic polymerization, or the like. Considering the production cost of the (meth)acrylic adhesive resin (a), the influence of the functional groups of the monomers, and the influence of ions on the surface of electronic components, polymerization by radical polymerization is preferred. When polymerization by radical polymerization is performed, the (meth)acrylic adhesive resin (a) of this embodiment preferably contains a radical polymerization initiator. The radical polymerization initiator of this embodiment is preferably benzoyl peroxide, di-t-butyl peroxide, dicumyl peroxide, 3,3,5-trimethylhexanoyl peroxide, di-2-ethylhexyl peroxydicarbonate, methyl ethyl ketone peroxide, t-butyl peroxyphthalate, t-butyl peroxybenzoate, di-t-butyl peroxyacetate, t-butyl peroxyisobutyrate, t-butylperoxy-2-hexanoate, or t-butylperoxy-2-ethylhexanoate. The peroxides may include one or more compounds selected from the group consisting of organic peroxides such as t-butylperoxy-3,5,5-trimethylhexanoate, acetyl peroxide, isobutyryl peroxide, octanoyl peroxide, t-butyl peroxide, and di-t-amyl peroxide; inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate; and azo compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile, and 4,4'-azobis-4-cyanovaleric acid.

[0057] When polymerized by emulsion polymerization, the (meth)acrylic adhesive resin (a) of this embodiment preferably contains one or more compounds selected from the group consisting of water-soluble inorganic peroxides such as ammonium persulfate, potassium persulfate, and sodium persulfate; and azo compounds having a carboxyl group in the molecule, such as water-soluble 4,4'-azobis-4-cyanovaleric acid. Furthermore, in consideration of the influence of ions on the surface of electronic components, the (meth)acrylic adhesive resin (a) more preferably contains an azo compound having a carboxyl group in the molecule, such as ammonium persulfate or 4,4'-azobis-4-cyanovaleric acid, and even more preferably contains an azo compound having a carboxyl group in the molecule, such as 4,4'-azobis-4-cyanovaleric acid.

[0058] From the viewpoint of suppressing misalignment of the electronic component 70 and improving the performance balance of adhesive strength, the adhesive resin layer (A) of this embodiment preferably further contains, in addition to the adhesive resin (Aa), a crosslinking agent (Ab) having two or more crosslinkable functional groups per molecule. The crosslinking agent (Ab) having two or more crosslinkable functional groups per molecule can be reacted with the functional groups of the adhesive resin (Aa) and used to adjust the adhesive strength and cohesive strength. The crosslinking agent (Ab) of the present embodiment is preferably an epoxy-based crosslinking agent such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, or resorcinol diglycidyl ether; an isocyanate-based crosslinking agent such as tetramethylene diisocyanate, hexamethylene diisocyanate, a toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, or tolylene diisocyanate; trimethylolpropane-tri-β-aziridinyl propionate, tetramethylolpropane-tri-β-aziridinyl propionate, or tetramethylolpropane-tri-β-aziridinyl propionate; The crosslinking agent may comprise one or more crosslinkers selected from the group consisting of aziridine-based crosslinkers such as tyrolmethane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'-bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy-based crosslinkers such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine-based crosslinkers such as hexamethoxymethylolmelamine. Among these, the crosslinking agent (Ab) of this embodiment preferably includes one or more crosslinking agents selected from the group consisting of epoxy-based crosslinking agents, isocyanate-based crosslinking agents, and aziridine-based crosslinking agents, from the viewpoint of being able to improve the performance balance between suppressing misalignment of the electronic component 70 and adhesive strength.

[0059] The content of the crosslinking agent (Ab) is preferably within a range such that the number of functional groups in the crosslinking agent (Ab) is not greater than the number of functional groups in the adhesive resin (Aa). However, an excess amount of the crosslinking agent (Ab) may be added as necessary when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The content of the crosslinking agent (Ab) in the adhesive resin layer (A) is preferably 0.1 parts by mass or more and 15 parts by mass or less per 100 parts by mass of the adhesive resin (Aa), from the viewpoint of suppressing misalignment of the electronic component 70 in the adhesive resin layer (A) and improving the performance balance between heat resistance and adhesion.

[0060] The adhesive resin layer (A) may contain additives such as plasticizers and tackifier resins as other components. When the adhesive resin layer (A) is a radiation-crosslinkable adhesive resin layer, it may contain various additives for radiation crosslinking. The total content of the adhesive resin (Aa) and the crosslinking agent (Ab) in the adhesive resin layer (A) is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, and even more preferably 80% by mass or more, based on 100% by mass of the entire adhesive resin layer (A), from the viewpoint of suppressing misalignment of the electronic component 70. Furthermore, the upper limit of the total content of the adhesive resin (Aa) and the crosslinking agent (Ab) in the adhesive resin layer (A) is not particularly limited, but may be, for example, 100% by mass or less.

[0061] In the pressure-sensitive adhesive film 50 of the present embodiment, from the viewpoint of being able to stably hold the electronic component 70 on the pressure-sensitive adhesive resin layer (A) when the support substrate is peeled off from the pressure-sensitive adhesive film 50, the total content of the gas-generating component and heat-expandable microspheres in the pressure-sensitive adhesive resin layer (A) is preferably 0.1% by mass or less, more preferably 0.05% by mass or less, even more preferably 0.01% by mass or less, based on 100% by mass of the entire pressure-sensitive adhesive resin layer (A). It is even more preferable that the pressure-sensitive adhesive resin layer (A) does not contain any gas-generating component or heat-expandable microspheres.

[0062] The adhesive resin layer (A) may be a single layer or a multilayer. The thickness of the adhesive resin layer (A) is preferably 1 μm or more and 100 μm or less, more preferably 3 μm or more and 75 μm or less, and even more preferably 5 μm or more and 50 μm or less.

[0063] The adhesive resin layer (A) can be formed, for example, by applying an adhesive onto the substrate layer 10. The adhesive may be dissolved in a solvent and applied as a coating liquid, or may be applied as an aqueous emulsion, or the liquid adhesive may be applied directly. Among these, the adhesive is preferably an aqueous emulsion coating liquid. Examples of aqueous emulsion coating liquids include coating liquids in which a (meth)acrylic adhesive resin (a), a silicone adhesive resin, a urethane adhesive resin, an olefin adhesive resin, a styrene adhesive resin, or the like is dispersed in water. An adhesive coating liquid dissolved in an organic solvent may also be used. The organic solvent is not particularly limited, and may be appropriately selected from known organic solvents in consideration of solubility and drying time. The organic solvent of the present embodiment preferably includes one or more selected from the group consisting of esters such as ethyl acetate and methyl acetate; ketones such as acetone and MEK; aromatics such as benzene, toluene, and ethylbenzene; linear or cyclic aliphatic solvents such as heptane, hexane, and cyclohexane; and alcohols such as isopropanol and butanol, and more preferably includes one or two selected from the group consisting of ethyl acetate and toluene.

[0064] The adhesive coating liquid can be applied using conventional coating methods such as a roll coater method, a reverse roll coater method, a gravure roll method, a bar coater method, a comma coater method, or a die coater method. The drying conditions for the applied adhesive are not particularly limited, but generally, drying is preferably performed for 10 seconds to 10 minutes at a temperature range of 80 to 200°C. Drying for 15 seconds to 5 minutes at 80 to 170°C is even more preferable. To sufficiently promote the crosslinking reaction between the crosslinker and the adhesive, the adhesive coating liquid may be heated at 40 to 80°C for approximately 5 to 300 hours after drying is complete.

[0065] The adhesive resin layer (A) of this embodiment may be formed by co-extrusion molding together with the base layer 10, or may be formed by further laminating a film-like adhesive resin layer (A) on the film-like base layer 10. In the examples described later, the adhesive resin layer (A) is first formed on the surface of a separator (release film), and then the adhesive resin layer (A) is bonded to another layer to produce an adhesive film.

[0066] [Adhesive Resin Layer (B)] In one aspect of the adhesive film 50 of the present embodiment, from the viewpoint of being able to suppress misalignment of the electronic component 70, an adhesive resin layer (B) is preferably provided on the side opposite to the adhesive resin layer (A) side of the base material layer 10. The adhesive resin layer (B) is a layer for fixing the adhesive film 50 to a support substrate, for example, when sealing electronic components with a sealing material in the manufacturing process of an electronic device.

[0067] The adhesive resin layer (B) is preferably a layer whose adhesive strength decreases in response to an external stimulus, thereby enabling the adhesive film 50 to be peeled from the support substrate by the external stimulus. The external stimulus preferably includes one or more selected from the group consisting of light irradiation and heat treatment, and more preferably includes heat treatment.

[0068] The adhesive resin layer (B) of this embodiment preferably contains a heat-expandable adhesive from the viewpoint of further improving releasability. The heat-expandable adhesive of this embodiment preferably contains an adhesive resin (B1) and one or more components selected from the group consisting of a gas-generating component and heat-expandable microspheres, and more preferably contains an adhesive resin (B1) and heat-expandable microspheres.

[0069] The adhesive resin layer (B) of this embodiment is a layer whose adhesive strength is reduced or lost when heated at a temperature preferably exceeding 150°C, more preferably 160°C or higher, even more preferably 170°C or higher, even more preferably 180°C or higher, even more preferably 190°C or higher, even more preferably 200°C or higher, and even more preferably 210°C or higher. Such an adhesive resin layer (B) can be obtained by selecting the gas-generating component or the type of heat-expandable microspheres in the adhesive resin layer (B). The reduction or loss of adhesive strength due to heating at a temperature exceeding 150°C can be evaluated, for example, by attaching the adhesive resin layer (B) side to a stainless steel plate, heating at 120°C for 1 hour, and then heating at a temperature exceeding 150°C for 2 minutes, and then measuring the peel strength from the stainless steel plate. The specific heating temperature when heating at a temperature exceeding 150°C is set to a temperature higher than the temperature at which gas is generated or the temperature at which the heat-expandable microspheres thermally expand, and is appropriately set depending on the gas generated and the type of heat-expandable microspheres. In this embodiment, loss of adhesive strength refers to, for example, a case where the 180° peel strength measured under conditions of 23° C. and a pulling rate of 300 mm / min becomes less than 0.5 N / 25 mm.

[0070] Examples of gas-generating components that can be used include azo compounds, azide compounds, Meldrum's acid derivatives, etc. Examples of gas-generating components include inorganic blowing agents such as ammonium carbonate, ammonium bicarbonate, sodium bicarbonate, ammonium nitrite, sodium boron hydroxide, and various azides; water; fluorinated alkane compounds such as trichloromonofluoromethane and dichloromonofluoromethane; azo compounds such as azobisisobutyronitrile, azodicarbonamide, and barium azodicarboxylate; paratoluenesulfonylhydrazide, diphenylsulfone-3,3'-disulfonylhydrazide, 4,4'-oxo-2,4'-dimethylaminobenzoate, and the like; Other examples of organic blowing agents that can be used include hydrazine compounds such as bis(benzenesulfonylhydrazide) and allylbis(sulfonylhydrazide); semicarbazide compounds such as p-toluylenesulfonylsemicarbazide and 4,4'-oxybis(benzenesulfonylsemicarbazide); triazole compounds such as 5-morpholyl-1,2,3,4-thiatriazole; and N-nitroso compounds such as N,N'-dinitrosopentamethylenetetramine and N,N'-dimethyl-N,N'-dinitrosoterephthalamide. The gas-generating component may be mixed with the adhesive resin (B1) or may be directly bonded to the adhesive resin (B1).

[0071] Heat-expandable microspheres can be prepared using, for example, microencapsulated blowing agents. Examples of such heat-expandable microspheres include microspheres in which a substance that easily gasifies and expands upon heating, such as isobutane, propane, or pentane, is encapsulated in an elastic shell. Examples of materials constituting the shell include vinylidene chloride-acrylonitrile copolymer, polyvinyl alcohol, polyvinyl butyral, polymethyl methacrylate, polyacrylonitrile, polyvinylidene chloride, and polysulfone. Heat-expandable microspheres can be produced by, for example, coacervation or interfacial polymerization.

[0072] To further improve thermal peelability, the total content of the gas-generating component and heat-expandable microspheres in the adhesive resin layer (B) is preferably 1 to 150 parts by mass, more preferably 3 to 150 parts by mass, even more preferably 5 to 100 parts by mass, even more preferably 7 to 50 parts by mass, even more preferably 11 to 25 parts by mass, even more preferably 12 to 20 parts by mass, and even more preferably 14 to 18 parts by mass, per 100 parts by mass of the adhesive resin (B1) in the adhesive resin layer (B). It is preferable to design the temperature at which gas is generated and the temperature at which the heat-expandable microspheres thermally expand are above 150°C.

[0073] The adhesive resin (B1) in the adhesive resin layer (B) of this embodiment preferably comprises one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, polyester adhesive resins, polyamide adhesive resins, fluorine adhesive resins and styrene adhesive resins; from the viewpoint of further improving peelability, more preferably comprises one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins and styrene adhesive resins; from the viewpoint of easily adjusting adhesive strength, more preferably comprises (meth)acrylic adhesive resin. As the (meth)acrylic adhesive resin that can be used for the adhesive resin (B1) of this embodiment, for example, the above-mentioned (meth)acrylic adhesive resin (a) can be used.

[0074] The adhesive resin layer (B) of this embodiment preferably further contains, in addition to the adhesive resin (B1), a crosslinking agent (B2) having two or more crosslinkable functional groups per molecule. The crosslinking agent (B2) having two or more crosslinkable functional groups per molecule is used to adjust the adhesive strength and cohesive strength by reacting with the functional groups of the adhesive resin (B1). The crosslinking agent (B2) of this embodiment is preferably an epoxy-based crosslinking agent such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, or resorcinol diglycidyl ether; an isocyanate-based crosslinking agent such as tetramethylene diisocyanate, hexamethylene diisocyanate, a toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, or tolylene diisocyanate; trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'- The adhesive composition contains one or more crosslinkers selected from the group consisting of aziridine crosslinkers such as bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy crosslinkers such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine crosslinkers such as hexamethoxymethylolmelamine. From the viewpoint of further improving the performance balance between adhesive strength and releasability, the adhesive composition contains more preferably one or more crosslinkers selected from the group consisting of epoxy crosslinkers, isocyanate crosslinkers, and aziridine crosslinkers.

[0075] The content of the crosslinking agent (B2) in the adhesive resin layer (B) is preferably within a range such that the number of functional groups in the crosslinking agent (B2) is not greater than the number of functional groups in the adhesive resin (B1). However, if necessary, an excess amount may be added when new functional groups are generated by the crosslinking reaction or when the crosslinking reaction is slow. The lower limit of the content of the crosslinking agent (B2) in the adhesive resin layer (B) is preferably 0.1 parts by mass or more and 10.0 parts by mass or less, more preferably 0.5 parts by mass or more and 8.0 parts by mass or less, even more preferably 1.0 parts by mass or more and 6.0 parts by mass or less, and even more preferably 2.0 parts by mass or more and 4.0 parts by mass or less, per 100 parts by mass of the adhesive resin (B1), in order to further improve the performance balance of adhesive strength, peelability, and storage stability.

[0076] The adhesive resin layer (B) of this embodiment preferably contains a tackifier resin in addition to the adhesive resin (B1) from the viewpoint of further improving adhesive strength. By incorporating a tackifier resin into the adhesive resin layer (B), it becomes easier to adjust the adhesion to the support substrate at around room temperature. The tackifier resin preferably has a softening point of 100°C or higher. Specific examples of tackifier resins include rosin-based resins such as rosin derivatives treated by esterification or the like; terpene-based resins such as α-pinene, β-pinene, dipentene, and terpene phenol; natural rosins such as gum, wood, and tall oil; petroleum resins obtained by hydrogenating, disproportionating, polymerizing, or maleating these natural rosins; and coumarone-indene resins. Among these tackifier resins, the adhesive resin layer (B) of this embodiment preferably contains a tackifier resin having a softening point in the range of 100 to 160°C, more preferably in the range of 120 to 150°C.

[0077] In the pressure-sensitive adhesive film 50 of this embodiment, from the viewpoint of further suppressing contamination of the device, at least one layer selected from the group consisting of the pressure-sensitive adhesive resin layer (B) and the intermediate layer (C) preferably contains a heat-resistant dye.

[0078] When the adhesive resin layer (B) of this embodiment contains a heat-resistant dye, the content of the heat-resistant dye in the adhesive resin layer (B) is, from the viewpoint of further suppressing equipment contamination, preferably 0.001% by mass or more and 10.0% by mass or less, more preferably 0.010% by mass or more and 9.0% by mass or less, even more preferably 0.020% by mass or more and 8.0% by mass or less, even more preferably 0.030% by mass or more and 7.0% by mass or less, even more preferably 0.050% by mass or more and 6.0% by mass or less, even more preferably 0.070% by mass or more and 5.0% by mass or less, and even more preferably 0.080% by mass or more and 4.0% by mass or less, when the entire adhesive resin layer (B) (solid content) is taken as 100% by mass.

[0079] When the adhesive resin layer (B) of this embodiment contains a heat-resistant dye, the content of the heat-resistant dye in the adhesive resin layer (B) is, from the viewpoint of further suppressing device contamination, preferably 0.01 parts by mass or more and 10.0 parts by mass or less, more preferably 0.03 parts by mass or more and 9.0 parts by mass or less, even more preferably 0.05 parts by mass or more and 8.0 parts by mass or less, even more preferably 0.06 parts by mass or more and 7.0 parts by mass or less, even more preferably 0.07 parts by mass or more and 6.0 parts by mass or less, even more preferably 0.08 parts by mass or more and 5.0 parts by mass or less, and even more preferably 0.09 parts by mass or more and 4.0 parts by mass or less, relative to 100 parts by mass of the adhesive resin (B1) in the adhesive resin layer (B).

[0080] From the viewpoint of further improving adhesion to the support substrate during operation, the content of the tackifier resin in the adhesive resin layer (B) is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 2 parts by mass or more and 50 parts by mass or less, even more preferably 3 parts by mass or more and 30 parts by mass or less, and even more preferably 5 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the adhesive resin (B1).

[0081] The adhesive resin layer (B) may contain additives such as plasticizers as other components. The lower limit of the total content of the adhesive resin (B1), crosslinking agent (B2), tackifier resin, heat-resistant dye, gas-generating component, and heat-expandable microspheres in the adhesive resin layer (B), when the entire adhesive resin layer (B) is taken as 100% by mass, is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more. The upper limit is not particularly limited, but is, for example, 100% by mass or less.

[0082] The adhesive resin layer (B) may be a single layer or a multilayer. The thickness of the adhesive resin layer (B) is preferably 3 μm or more and 300 μm or less, more preferably 5 μm or more and 200 μm or less, even more preferably 10 μm or more and 100 μm or less, and still more preferably 25 μm or more and 50 μm or less, from the viewpoint of further improving the balance of the handling properties, adhesiveness, and peelability of the adhesive film 50.

[0083] [Intermediate layer (C)] In one aspect of the pressure-sensitive adhesive film 50 of the present embodiment, from the viewpoint of being able to suppress misalignment of the electronic component 70 and improving the performance balance of the conformability and adhesion of the pressure-sensitive adhesive film 50 to the electronic component and the supporting substrate, the pressure-sensitive adhesive film 50 preferably further comprises an intermediate layer (C) between at least one selected from the group consisting of the adhesive resin layer (A) and the base layer 10 and the base layer 10 and the adhesive resin layer (B), and more preferably comprises an intermediate layer (C) between the base layer 10 and the adhesive resin layer (B). The intermediate layer (C) of the present embodiment is, for example, a layer for imparting conformability and adhesion to the electronic component and the supporting substrate to the pressure-sensitive adhesive film 50.

[0084] The intermediate layer (C) of this embodiment preferably contains, as the thermoplastic resin (C1), one or more selected from the group consisting of polyolefin resins, ethylene-carboxylic anhydride copolymers, ethylene-epoxy copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-ethylenically unsaturated acid copolymers, ethylene-vinyl ester copolymers, polystyrene resins, and (meth)acrylic resins, and more preferably contains a (meth)acrylic resin from the viewpoint of further improving releasability. Examples of the (meth)acrylic resin that can be used for the thermoplastic resin (C1) of this embodiment include the above-mentioned (meth)acrylic adhesive resin (a).

[0085] The intermediate layer (C) of this embodiment preferably further contains, in addition to the thermoplastic resin (C1), a crosslinking agent (C2) having two or more crosslinkable functional groups per molecule. The crosslinking agent (C2) having two or more crosslinkable functional groups per molecule is reacted with the functional groups of the thermoplastic resin (C1) to adjust the adhesive strength and cohesive strength. The crosslinking agent (C2) of the present embodiment is preferably an epoxy-based crosslinking agent such as sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, neopentyl glycol diglycidyl ether, or resorcinol diglycidyl ether; an isocyanate-based crosslinking agent such as tetramethylene diisocyanate, hexamethylene diisocyanate, a toluene diisocyanate triadduct of trimethylolpropane, polyisocyanate, diphenylmethane diisocyanate, or tolylene diisocyanate; trimethylolpropane-tri-β-aziridinylpropionate, tetramethylolmethane-tri-β-aziridinylpropionate, N,N'-diphenylmethane-4,4'- The adhesive composition contains one or more crosslinkers selected from the group consisting of aziridine crosslinkers such as bis(1-aziridinecarboxamide), N,N'-hexamethylene-1,6-bis(1-aziridinecarboxamide), N,N'-toluene-2,4-bis(1-aziridinecarboxamide), and trimethylolpropane-tri-β-(2-methylaziridine)propionate; tetrafunctional epoxy crosslinkers such as N,N,N',N'-tetraglycidyl-m-xylylenediamine and 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane; and melamine crosslinkers such as hexamethoxymethylolmelamine. From the viewpoint of further improving the performance balance between adhesive strength and releasability, the adhesive composition contains more preferably one or more crosslinkers selected from the group consisting of epoxy crosslinkers, isocyanate crosslinkers, and aziridine crosslinkers.

[0086] The content of the crosslinking agent (C2) in the intermediate layer (C) of this embodiment is preferably within a range such that the number of functional groups in the crosslinking agent (C2) is not greater than the number of functional groups in the thermoplastic resin (C1). However, an excess amount may be added as necessary when new functional groups are generated in the crosslinking reaction or when the crosslinking reaction is slow. From the viewpoint of further improving the performance balance of adhesive strength, peelability, and storage stability, the content of the crosslinking agent (C2) in the intermediate layer (C) of this embodiment is preferably 0.1 parts by mass or more and 10.0 parts by mass or less, more preferably 0.5 parts by mass or more and 8.0 parts by mass or less, even more preferably 1.0 parts by mass or more and 6.0 parts by mass or less, and even more preferably 2.0 parts by mass or more and 4.0 parts by mass or less, per 100 parts by mass of the thermoplastic resin (C1).

[0087] The intermediate layer (C) of this embodiment preferably contains a tackifier resin in addition to the thermoplastic resin (C1) from the viewpoint of further improving adhesive strength. By incorporating a tackifier resin into the intermediate layer (C), it becomes easier to adjust the adhesion to the support substrate at around room temperature. The tackifier resin preferably has a softening point of 100°C or higher. Specific examples of tackifier resins include rosin-based resins such as rosin derivatives treated by esterification or the like; terpene-based resins such as α-pinene, β-pinene, dipentene, and terpene phenol; natural rosins such as gum, wood, and tall oil; petroleum resins obtained by hydrogenating, disproportionating, polymerizing, or maleating these natural rosins; and coumarone-indene resins. Among these tackifier resins, the intermediate layer (C) of this embodiment preferably contains a tackifier resin having a softening point in the range of 100 to 160°C, more preferably in the range of 120 to 150°C.

[0088] In order to further improve adhesion to the support substrate during operation, the content of the tackifier resin in the intermediate layer (C) of this embodiment is preferably 1 part by mass or more and 100 parts by mass or less, more preferably 2 parts by mass or more and 50 parts by mass or less, even more preferably 3 parts by mass or more and 30 parts by mass or less, and even more preferably 3 parts by mass or more and 10 parts by mass or less, relative to 100 parts by mass of the thermoplastic resin (C1).

[0089] In the pressure-sensitive adhesive film 50 of this embodiment, the intermediate layer (C) preferably contains a heat-resistant dye, from the viewpoint of further suppressing contamination of the device.

[0090] When the intermediate layer (C) of this embodiment contains a heat-resistant dye, the content of the heat-resistant dye in the intermediate layer (C) is preferably 0.001% by mass or more and 10.0% by mass or less, more preferably 0.010% by mass or more and 9.0% by mass or less, even more preferably 0.020% by mass or more and 8.0% by mass or less, even more preferably 0.030% by mass or more and 7.0% by mass or less, even more preferably 0.050% by mass or more and 6.0% by mass or less, even more preferably 0.070% by mass or more and 5.0% by mass or less, and even more preferably 0.080% by mass or more and 4.0% by mass or less, when the entire intermediate layer (C) (solid content) is taken as 100% by mass, from the viewpoint of further suppressing device contamination.

[0091] When the intermediate layer (C) of this embodiment contains a heat-resistant dye, the content of the heat-resistant dye in the intermediate layer (C) is, from the viewpoint of further suppressing device contamination, preferably from 0.01 to 10.0 parts by mass, more preferably from 0.03 to 9.0 parts by mass, even more preferably from 0.05 to 8.0 parts by mass, still more preferably from 0.06 to 7.0 parts by mass, even more preferably from 0.07 to 6.0 parts by mass, even more preferably from 0.08 to 5.0 parts by mass, and even more preferably from 0.09 to 4.0 parts by mass, relative to 100 parts by mass of the thermoplastic resin (C1) in the intermediate layer (C).

[0092] The intermediate layer (C) of this embodiment may contain additives such as plasticizers as other components. The total content of the thermoplastic resin (C1), crosslinking agent (C2), tackifier resin, heat-resistant dye, gas-generating component, and heat-expandable microspheres in the intermediate layer (C) of this embodiment is preferably 50% by mass or more, more preferably 70% by mass or more, even more preferably 90% by mass or more, and even more preferably 95% by mass or more, based on 100% by mass of the entire intermediate layer (C). The upper limit is not particularly limited, but is, for example, 100% by mass or less.

[0093] The thickness of the intermediate layer (C) in this embodiment is preferably 1 μm or more and 500 μm or less, more preferably 5 μm or more and 300 μm or less, and even more preferably 10 μm or more and 100 μm or less, from the viewpoint of improving the unevenness absorbency of the adhesive film 50.

[0094] [Other Layers] The pressure-sensitive adhesive film 50 of this embodiment may further include, for example, an easy-adhesion layer or the like between the layers, as long as the effect of this embodiment is not impaired.

[0095] [Method for Manufacturing Electronic Device] The method for manufacturing an electronic device of this embodiment will be described with reference to the drawings. Figures 4 and 5 are cross-sectional views that schematically show the method for manufacturing an electronic device of this embodiment according to the present invention. The method for manufacturing an electronic device of this embodiment preferably includes a step (a) of preparing a structure 100 including an adhesive film 50 and an electronic component 70 attached to the adhesive film 50, and a step (b) of sealing the electronic component 70 with a sealant 60.

[0096] First, in step (a), a structure 100 including an adhesive film 50 and an electronic component 70 attached to the adhesive film 50 is prepared.

[0097] Such a structure can be obtained by placing electronic components 70 on adhesive film 50 .

[0098] The surface of the electronic component 70 has an uneven structure 75 due to, for example, the presence of electrodes. Furthermore, when mounting an electronic device on a mounting surface, the electrodes are bonded to the electrodes formed on the mounting surface to form an electrical connection between the electronic device and the mounting surface (such as the mounting surface of a printed circuit board). Examples of the electrodes include bump electrodes such as ball bumps, printed bumps, stud bumps, plated bumps, and pillar bumps. That is, the electrodes are typically convex electrodes. These bump electrodes may be used alone or in combination of two or more types. The metal species constituting the bump electrodes are not particularly limited, and examples include silver, gold, copper, tin, lead, bismuth, and alloys thereof. These metal species may be used alone or in combination of two or more types.

[0099] The electronic component 70 may be attached to either side of the adhesive film 50, but if the adhesive film 50 has an adhesive resin layer (A), the electronic component 70 is preferably attached to the adhesive resin layer (A) of the adhesive film 50 in order to prevent the electronic component 70 from shifting out of position.

[0100] Here, the structure 100 preferably further comprises a support substrate attached to the surface of the adhesive film 50 opposite to the surface to which the electronic component 70 is attached.

[0101] The support substrate may be attached to either side of the adhesive film 50 as long as it is attached to the side other than the side of the adhesive film 50 to which the electronic component 70 is attached. However, when the adhesive film 50 has an adhesive resin layer (B), the electronic component 70 is preferably attached to the adhesive resin layer (B) of the adhesive film 50 in order to prevent the electronic component 70 from shifting out of position.

[0102] The structure 100 further including a support substrate can be produced, for example, by the following procedure. First, the adhesive film 50 is attached to the support substrate so that the adhesive resin layer (B) faces the support substrate. A protective film called a separator may be attached to the adhesive resin layer (B), and the protective film can be peeled off, and the exposed surface of the adhesive resin layer (B) can be attached to the surface of the support substrate. For example, a quartz substrate, a glass substrate, a SUS substrate, etc. can be used as the support substrate.

[0103] Thereafter, the electronic component 70 is placed on the surface of the adhesive film 50 opposite to the surface to which the support substrate is attached, by the same procedure as above, and thus the structure 100 can be obtained.

[0104] Next, in step (b), the electronic component 70 is sealed with the sealing material 60. The electronic component 70 is sealed by covering it with the sealing material 60. Here, when the adhesive film 50 includes an adhesive resin layer (B) and the adhesive resin layer (B) contains at least one selected from a gas-generating component and heat-expandable microspheres, the temperature at which the sealing material 60 is used for sealing is preferably within a range that does not exceed the temperature at which gas is generated or the temperature at which the heat-expandable microspheres thermally expand.

[0105] In the step (b) of sealing the electronic components 70 with the sealing material 60, the plurality of electronic components 70 may be sealed together or individually with the sealing material 60. The method for individually covering the plurality of electronic components 70 with the sealing material 60 preferably includes one or more methods selected from the group consisting of a 3D printer method, a spray method, a screen printing method, and an inkjet method, and more preferably includes a 3D printer method.

[0106] As the sealing material 60, any known sealing material having high insulating properties can be used, but the sealing material 60 preferably includes an epoxy resin-based sealing material, which improves the affinity of the sealing material 60 to the adhesive film 50 and enables more uniform sealing of the electronic component 70. Examples of such epoxy resin-based sealing materials that can be used include the T693 / R4000 series, T693 / R1000 series, and T693 / R5000 series manufactured by Nagase ChemteX Corporation. The sealing material 60 may be solid or liquid, but is preferably liquid, from the viewpoints of enabling the sealing process to be carried out at low temperature and low pressure and suppressing misalignment of the electronic component 70 during the sealing process.

[0107] From the viewpoint of suppressing misalignment of the electronic component 70, the thickness of the sealing material 60 after covering the electronic component 70 is preferably 1.0 μm or more and 2000.0 μm or less, more preferably 1.5 μm or more and 2000.0 μm or less, even more preferably 5.0 μm or more and 2000.0 μm or less, even more preferably 10.0 μm or more and 1500.0 μm or less, even more preferably 30.0 μm or more and 1500.0 μm or less, even more preferably 50.0 μm or more and 1000.0 μm or less, even more preferably 100.0 μm or more and 1000.0 μm or less, even more preferably 200.0 μm or more and 500.0 μm or less, and even more preferably 300.0 μm or more and 500.0 μm or less.

[0108] The sealing temperature in the step of sealing the electronic component 70 with the sealing material 60 is preferably 10° C. or higher and 100° C. or lower, more preferably 10° C. or higher and 90° C. or lower, even more preferably 15° C. or higher and 80° C. or lower, and even more preferably 20° C. or higher and 70° C. or lower, from the viewpoint of improving the work efficiency of the step of sealing the electronic component 70 with the sealing material 60 while suppressing misalignment of the electronic component 70. Note that the sealing temperature in this embodiment refers to the set temperature in the device used to seal the electronic component 70.

[0109] The sealing pressure in the step of sealing the electronic component 70 with the sealing material 60 is preferably 30 kPa or more and 150 kPa or less, more preferably 50 kPa or more and 150 kPa or less, even more preferably 70 kPa or more and 130 kPa or less, and even more preferably 90 kPa or more and 110 kPa or less, from the viewpoint of improving the reliability of the electronic device while suppressing misalignment of the electronic component 70. Furthermore, it is more preferable that the sealing pressure in the step of sealing the electronic component 70 with the sealing material 60 is normal pressure. Note that the sealing pressure in this embodiment refers to the set pressure in the device used to seal the electronic component 70.

[0110] The method for manufacturing an electronic device according to this embodiment preferably further includes, after step (b), step (c) of curing the encapsulant 60 by one or two methods selected from the group consisting of light irradiation and heat treatment. This fixes the electronic component 70 and prevents the electronic component 70 from shifting out of position.

[0111] The method of curing the encapsulant 60 by light irradiation is preferably a method of crosslinking and curing the encapsulant 60 by irradiating the encapsulant 60 with light such as ultraviolet light. The light source used in this method is preferably a light source capable of irradiating ultraviolet light containing wavelength components capable of exciting a photoinitiator, and more preferably a light source capable of irradiating ultraviolet light containing components with wavelengths of less than 300 nm. The method of curing the encapsulant 60 by heat treatment is preferably a method of curing the encapsulant 60 by thermal crosslinking using an oven, thermal crosslinking using a hot plate, or thermal crosslinking using infrared radiation. In the case of thermal crosslinking, the heating temperature is, for example, 100°C or higher and 150°C or lower, and the heating time is, for example, 10 to 180 minutes. The heating temperature is preferably a temperature that does not exceed the temperature at which gas contained in the pressure-sensitive adhesive film 50 generates or the temperature at which the heat-expandable microspheres thermally expand.

[0112] The method for producing an electronic device according to the present embodiment preferably further includes, after step (c), step (d) of peeling the adhesive film 50 from the electronic component 70. This step results in the electronic device 200. Examples of methods for peeling the adhesive film 50 from the electronic component 70 include a mechanical peeling method and a method of reducing the adhesive strength of the surface of the adhesive film 50 before peeling.

[0113] (Other Steps) The method for manufacturing an electronic device of the present embodiment may further include, between steps (c) and (d), a step of reducing the adhesive strength of the adhesive resin layer (B) by heat treatment to peel off the support substrate from the structure 100. For example, after sealing the electronic component 70, the support substrate can be easily removed from the adhesive film 50 by heating it to a temperature exceeding 180°C to reduce the adhesive strength of the adhesive resin layer (B).

[0114] The adhesive film 50 of this embodiment can be preferably used to manufacture an electronic device including a fan-out package. That is, the electronic device obtained by the manufacturing method of the electronic device of this embodiment includes a fan-out package. In a fan-out package, terminals can be spread to the outside of the chip (fan out), so it can be used in applications where the number of terminals is large compared to the chip area. In addition, since a package substrate is not required, it can also be made thinner.

[0115] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations can also be adopted.

[0116] The present invention is not limited to the above-described embodiment, and any modifications and improvements that can achieve the object of the present invention are included in the present invention.

[0117] The present invention will be specifically explained below with reference to examples, but the present invention is not limited thereto.

[0118] The details of the method for producing the adhesive film are as follows.

[0119] <Raw Material Components> (Dyes) Dyes 1: Phthalocyanine dye (LIONOL BLUE SL, C.I. Pigment Blue 15:3, manufactured by Toyocolor Co., Ltd., molecular weight 576.1, melting point 600°C) Dyes 2: Phthalocyanine dye (LIONOL GREEN 8390, C.I. Pigment Green 7, manufactured by Toyocolor Co., Ltd., molecular weight 1127.2, melting point 480°C) Dyes 3: Quinacridone dye (C.I. Pigment Red 19, molecular weight 456.5, melting point 300°C or higher) Dyes 4: Isoindolinone dye (C.I. Pigment Yellow 110, molecular weight 641.9, melting point 300°C) Dye 5: Phthalocyanine pigment dispersion (MT-170 Blue, C.I. Pigment Blue 15:3, manufactured by Tokushiki Co., Ltd., molecular weight 576.1, melting point 600°C, solid content 1% by mass) Dye 6: Phthalocyanine pigment dispersion (MT-160 Green, C.I. Pigment Green 7, manufactured by Tokushiki Co., Ltd., molecular weight 1127.2, melting point 480°C, solid content 1% by mass) Dye 7: Quinacridone pigment dispersion (MT-120 Red, C.I. Pigment Red 19, manufactured by Tokushiki Co., Ltd., molecular weight 456.5, melting point 300°C or higher, solid content 1% by mass) Dye 8: Isoindolinone pigment dispersion (MT-150 Yellow, C.I. Pigment Yellow 110, manufactured by Tokushiki Co., Ltd., molecular weight 641.9, melting point 300°C, solid content 1% by mass) Dye 9: Anthraquinone dye (MITSUI PG RED G, molecular weight 331.3, melting point 180°C)

[0120] (Adhesive Resin Solution S) 0.536 parts by mass of t-butylperoxy-2-ethylhexanoate (manufactured by NOF Corporation, trade name: PERBUTYL O (registered trademark)), 34.9 parts by weight of 2-ethylhexyl acrylate, 41 parts by mass of butyl acrylate, 14.7 parts by mass of ethyl acrylate, and 9.4 parts by mass of 2-hydroxyethyl methacrylate were added to a mixed solvent containing ethyl acetate and toluene, and solution polymerization was carried out at 83 to 87°C for 11 hours with stirring, to obtain a (meth)acrylic adhesive resin solution (adhesive resin solution S) with a solids concentration of 45% by mass.

[0121] (Dye Dispersion Liquid D1) 99 parts by mass of ethyl acetate was added to 1 part by mass of Dye 1. Then, using a homogenizer (HM-300, manufactured by AS ONE Corporation), the mixture was dispersed at 8000 rpm for 10 minutes to obtain Dye Dispersion Liquid D1.

[0122] (Dye Dispersions D2 to D4, D9) Dye dispersions D2 to D4 and D9 were obtained in the same manner as dye dispersion D1, except that dye 2 to 4 and 9 were used instead of dye 1, respectively.

[0123] (Dye Dispersions D5 to D8) Dye Dispersions D5 to D8 were obtained in the same manner as Dye Dispersion D1, except that ethyl acetate was not added to 100 parts by mass of Dye 5 to 8, and Dye 5 to 8 were directly dispersed using a homogenizer.

[0124] (Resin Emulsion 1) Using 0.5 parts by mass of ammonium peroxodisulfate as a polymerization initiator, 63 parts by mass of 2-ethylhexyl acrylate, 21 parts by mass of butyl acrylate, 9 parts by mass of methyl methacrylate, 3 parts by mass of 2-hydroxyethyl methacrylate, 2 parts by mass of methacrylic acid, 1 part by mass of acrylamide, 1 part by mass of polytetramethylene glycol diacrylate (manufactured by NOF Corporation, product name: Blemmer ADT-250), and 2 parts by mass of an aqueous solution of polyoxyethylene nonylpropenyl phenyl ether ammonium sulfate (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., product name: Aqualon HS-1025) were emulsion-polymerized in deionized water at 70°C for 8 hours. After completion of polymerization, the pH was adjusted to 7 with aqueous ammonia. As a result, a (meth)acrylic resin emulsion 1 with a solids concentration of 56.5% by mass was obtained.

[0125] (Resin Emulsion 2) Using 0.5 parts by mass of 4,4'-azobis-4-cyanovaleric acid (manufactured by Otsuka Chemical Co., Ltd., product name: ACVA) as a polymerization initiator, 74 parts by mass of butyl acrylate, 14 parts by mass of methyl methacrylate, 9 parts by mass of 2-hydroxyethyl methacrylate, 2 parts by mass of methacrylic acid, 1 part by mass of acrylamide, and 3 parts by mass of an aqueous solution of polyoxyethylene nonylpropenylphenyl ether ammonium sulfate (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd., product name: Aqualon HS-1025) were emulsion-polymerized in deionized water at 70°C for 8 hours. After completion of polymerization, the pH was adjusted to 7 with aqueous ammonia. As a result, a (meth)acrylic resin emulsion 2 with a solids concentration of 42.5% by mass was obtained.

[0126] (Resin solution 1) 49 parts by mass of ethyl acrylate, 20 parts by mass of 2-ethylhexyl acrylate, 21 parts by mass of methyl acrylate, 10 parts by mass of glycidyl methacrylate, and 0.5 parts by mass (solids content equivalent) of a benzoyl peroxide-based polymerization initiator as a polymerization initiator were reacted in 65 parts by mass of toluene and 50 parts by mass of ethyl acetate at 80° C. for 10 hours. After completion of the reaction, the resulting solution was cooled, and 25 parts by mass of xylene, 5 parts by mass of acrylic acid, and 0.5 parts by mass of tetradecyldimethylbenzylammonium chloride were added to the cooled solution, and the mixture was reacted at 85° C. for 32 hours while blowing air in, to obtain a (meth)acrylic resin solution (resin solution 1) with a solids concentration of 45% by mass.

[0127] (Adhesive coating solution A for forming adhesive resin layer (A)) 42.6 parts by mass of resin emulsion 1, 57.4 parts by mass of resin emulsion 2, 0.4 parts by mass of dimethylethanolamine, 5 parts by mass of an epoxy compound (manufactured by Nagase ChemteX Corporation, product name: EX-1610) as a crosslinking agent, 13 parts by mass of diethylene glycol monobutyl ether, and ２ 20 parts by mass of O were mixed to prepare a pressure-sensitive adhesive coating solution A.

[0128] (Adhesive coating solution B1 for forming adhesive resin layer (B)) 100 parts by mass of adhesive resin solution S, 2.25 parts by weight of polymerized rosin ester tackifier (manufactured by Arakawa Chemical Industries, Ltd., product name: Pencel D-125) (5 parts by weight per 100 parts by mass of adhesive resin in terms of solid content), 1.2 parts by weight of isocyanate crosslinking agent (manufactured by Mitsui Chemicals, Inc., product name: Olester P49-75S) (2.7 parts by weight per 100 parts by mass of adhesive resin in terms of solid content), heat-expandable microspheres (manufactured by Sekisui Chemical Co., Ltd., product name: Advancel EM-503, maximum particle diameter D １００ 6.75 parts by mass (15 parts by mass, in terms of solid content, per 100 parts by mass of adhesive resin) of the adhesive resin dispersion D1 (38 μm, mesh size 38 μm, the fraction that passed through the sieve when classified using a metal mesh was used) and 4.5 parts by mass of the pigment dispersion D1 (0.1 parts by mass of pigment, in terms of solid content, per 100 parts by mass of adhesive resin), and the solid content concentration was adjusted to 30% by mass with ethyl acetate to prepare an adhesive coating solution B1.

[0129] (Adhesive coating liquids B2 to 12 for forming adhesive resin layer (B)) Adhesive coating liquids B2 to 12 were each obtained in the same manner as adhesive coating liquid B1, except that the pigment dispersion liquid was changed to the pigment dispersion liquid shown in Table 1 and the amount of pigment added was changed so that the pigment content in the adhesive resin layer (B) was the value shown in Table 1.

[0130] <Preparation of Adhesive Film> [Example 1] First, the adhesive coating liquid B1 was applied to a silicone release-treated separator and dried at 120 ° C. for 3 minutes to form a resin film B with a thickness of 47 μm. Then, this resin film B was attached to the second surface of a polyethylene terephthalate film (manufactured by Toray Industries, Inc., product name: Lumirror S10, thickness: 38 μm, double-sided corona-treated product) serving as a substrate layer to obtain an adhesive resin layer (B). Furthermore, the adhesive coating liquid A was applied to a silicone release-treated separator and dried at 120 ° C. for 3 minutes to form a resin film A with a thickness of 13 μm. This resin film A was attached to the first surface of the substrate layer (the surface of the substrate layer opposite to the surface on which the adhesive resin layer (B) was provided). This resulted in the adhesive resin layer (A). As a result, an adhesive film comprising, in this order, the adhesive resin layer (A), the substrate layer, and the adhesive resin layer (B) was obtained. The resulting adhesive film was heated at 60° C. for 5 days.

[0131] [Examples 2 to 11, Comparative Example 1] As shown in Table 1, adhesive films were obtained in the same manner as in Example 1, except that adhesive coating solutions B2 to B12 were used instead of the adhesive coating solution B1 for forming the adhesive resin layer (B).

[0132] <Evaluation> (1) Maximum absorption wavelength λ ｍａｘ and absorbance. 0.5 g of dyes 1 to 9 were placed in a 5 cm diameter beaker, and a 5 x 5 cm glass plate (manufactured by SCHOTT, product name: TEMPAX Float (registered trademark)) was placed on top to cover the beaker. Next, the beaker covered with the glass plate was heated on a hot plate at 250°C for 8 hours. After heating, the glass plate was removed, and the UV-visible absorption spectrum of the glass plate was measured in the wavelength range of 360 to 800 nm using a UV-visible spectrophotometer, and the maximum absorption wavelength λ ｍａｘ The absorbance was calculated at the maximum absorption wavelength λ ｍａｘ The absorbance measurement results are shown in Table 1.

[0133] (2) Evaluation of Color Unevenness The adhesive films obtained in each Example and Comparative Example were observed from the adhesive resin layer (A) side using a transmission electron microscope at a magnification of 20 times, and color unevenness was evaluated according to the following criteria. The results are shown in Table 1. A: No color unevenness due to the dye was observed. B: Color unevenness due to the dye was observed (dye particles were visible).

[0134] (3) Evaluation of Equipment Contamination The adhesive films obtained in each Example and Comparative Example were heated at 260°C for 168 hours in an oven with a white cloth covering the exhaust port. After heating, the coloring of the cloth was checked and evaluated according to the following criteria: A: No coloring due to the dye was observed B: Coloring due to the dye was observed

[0135]

[0136] As in each example, the adhesive film contained a heat-resistant dye whose absorbance measured under specific conditions was in a specific range, thereby making it possible to suppress contamination of the device.

[0137] This application claims priority based on Japanese Patent Application No. 2024-051327, filed March 27, 2024, the disclosure of which is incorporated herein by reference in its entirety.

[0138] A: adhesive resin layer B: adhesive resin layer C: intermediate layer 10: base layer 50: adhesive film 60: sealing material 70: electronic component 75: uneven structure 80: supporting substrate 100: structure 200: electronic device

Claims

1. An adhesive film containing a heat-resistant dye, wherein the maximum absorption wavelength λ of the heat-resistant dye is measured by the following method: ｍａｘ An adhesive film having an absorbance of 0.50 or less at 1000 kJ / cm2. (Method) 0.5 g of the heat-resistant dye is placed in a beaker having a diameter of 5 cm, and a 5 x 5 cm glass plate is placed on top of the beaker to cover it. Next, the beaker covered with the glass plate is heated on a hot plate at 250°C for 8 hours. After heating, the glass plate is removed, and the ultraviolet-visible absorption spectrum of the glass plate is measured in the wavelength range of 360 to 800 nm using an ultraviolet-visible spectrophotometer, and the maximum absorption wavelength λ ｍａｘ The absorbance at 2. The maximum absorption wavelength λ in the wavelength range of 360 to 800 nm ｍａｘ The adhesive film according to claim 1, wherein the thickness is 360 nm or more and 600 nm or less.

3. The adhesive film according to claim 1 or 2, wherein the heat-resistant coloring matter comprises a heat-resistant pigment.

4. The adhesive film according to claim 3, wherein the heat-resistant pigment comprises one or more selected from the group consisting of phthalocyanine dyes, quinacridone dyes and isoindolinone dyes.

5. The adhesive film according to any one of claims 1 to 4, wherein the heat-resistant dye has a molecular weight of 350 or more.

6. The adhesive film according to any one of claims 1 to 5, wherein the melting point of the heat-resistant dye is 200°C or higher.

7. An adhesive film described in any one of claims 1 to 6, wherein the content of the heat-resistant dye is 0.001% by mass or more and 10.0% by mass or less, when the entire adhesive film is taken as 100% by mass.

8. An adhesive film according to any one of claims 1 to 7, comprising an adhesive resin layer (A) and a substrate layer, wherein at least one layer selected from the group consisting of the adhesive resin layer (A) and the substrate layer contains the heat-resistant dye.

9. An adhesive film according to any one of claims 1 to 7, comprising an adhesive resin layer (A), a base layer, and an adhesive resin layer (B) in this order, and at least one layer selected from the group consisting of the adhesive resin layer (A), the base layer, and the adhesive resin layer (B) contains the heat-resistant dye.

10. An adhesive film according to any one of claims 1 to 7, comprising an adhesive resin layer (A), a substrate layer, and an adhesive resin layer (B) in this order, and further comprising an intermediate layer (C) between at least one layer selected from the group consisting of the adhesive resin layer (A) and the substrate layer, and between the substrate layer and the adhesive resin layer (B), and at least one layer selected from the group consisting of the adhesive resin layer (A), the intermediate layer (C), the substrate layer, and the adhesive resin layer (B) contains the heat-resistant dye.

11. The adhesive film according to claim 9 or 10, wherein the adhesive resin layer (B) is a layer whose adhesive strength decreases upon heat treatment.

12. The adhesive film according to any one of claims 9 to 11, wherein the adhesive resin layer (B) contains a heat-expandable adhesive.

13. The adhesive film according to claim 12, wherein the thermally expandable adhesive is an adhesive whose adhesive strength is reduced or lost when heated at a temperature exceeding 150°C.

14. An adhesive film according to any one of claims 9 to 13, wherein the adhesive resin layer (B) contains one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, and styrene adhesive resins.

15. The adhesive film according to any one of claims 9 to 14, wherein the thickness of the adhesive resin layer (B) is 3 μm or more and 300 μm or less.

16. The adhesive film according to any one of claims 9 to 15, wherein at least one layer selected from the group consisting of the adhesive resin layer (B) and the intermediate layer (C) contains the heat-resistant dye.

17. The adhesive film according to claim 10 or 16, wherein the intermediate layer (C) comprises one or more selected from the group consisting of polyolefin resins, ethylene-carboxylic anhydride copolymers, ethylene-epoxy copolymers, ethylene-(meth)acrylic acid ester copolymers, ethylene-ethylenically unsaturated acid copolymers, ethylene-vinyl ester copolymers, polystyrene resins, and (meth)acrylic resins.

18. The adhesive film according to claim 10, 16 or 17, wherein the thickness of the intermediate layer (C) is 1 μm or more and 500 μm or less.

19. An adhesive film according to any one of claims 8 to 18, wherein the adhesive resin layer (A) contains one or more selected from the group consisting of (meth)acrylic adhesive resins, silicone adhesive resins, urethane adhesive resins, olefin adhesive resins, and styrene adhesive resins.

20. The adhesive film according to any one of claims 8 to 19, wherein the total content of the gas-generating component and heat-expandable microspheres in the adhesive resin layer (A) is 0.1 mass% or less, when the entire adhesive resin layer (A) is taken as 100 mass%.

21. The adhesive film according to any one of claims 8 to 20, wherein the thickness of the adhesive resin layer (A) is 1 μm or more and 100 μm or less.

22. The adhesive film according to any one of claims 1 to 21, which is capable of temporarily fixing electronic components when the electronic components are sealed with a sealing material.

23. A method for manufacturing an electronic device, comprising: (a) a step of preparing a structure comprising the adhesive film according to any one of claims 1 to 22 and an electronic component attached to the adhesive film; and (b) a step of sealing the electronic component with a sealing material.

24. The method for manufacturing an electronic device according to claim 23, wherein the encapsulant comprises an epoxy resin-based encapsulant.

25. The method of manufacturing an electronic device according to claim 23 or 24, wherein the electronic device comprises a fan-out package.

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