TW202403000A - Energy ray-curable film-shaped transparent adhesive, device comprising same, and device manufacturing method - Google Patents

Abstract

Provided is an energy ray-curable film-shaped transparent adhesive comprising an epoxy resin, a phenoxy resin, and a photocationic polymerization initiator containing antimony at an anionic site. Also provided are a device comprising the film-shaped transparent adhesive, and a method for manufacturing the device using the film-shaped transparent adhesive.

Description

Energy ray curable film-like transparent adhesive, device containing the same, and method of manufacturing the device

The present invention relates to an energy ray curable film-like transparent adhesive, a device containing the same, and a manufacturing method of the device.

Image sensors (image sensors) such as CMOS image sensors and CCD image sensors are incorporated into photographic equipment such as digital still cameras or digital video cameras. The image sensor uses a photodiode to photoelectrically convert the incident light into an electrical signal, and then processes the signal to form a digital image. If necessary, a color filter, a microlens, etc. are disposed on the surface of the photodiode, and a transparent protective film such as a glass plate is usually disposed on the surface of the laminated body. Such a transparent protective film is fixed via a film-like adhesive or the like. Adhesives used for bonding and fixing transparent protective films for image sensors require sufficient transparency to allow light to pass through them. On the other hand, in image display devices, there are also cases in which functional elements (organic electroluminescence (organic EL) elements, liquid crystal panels, micro-light-emitting diodes (micro-LEDs), etc.) are arranged on a supporting base material. Semiconductor elements such as transistors, etc.), and functional layers (protective layers, gas barrier layers (sealing layers), hard coats, etc.) are arranged on the surfaces of functional elements. In some cases, sufficient transparency is also required for the adhesive used for bonding and fixing these functional elements and functional layers. Film adhesives themselves are known to have various compositions and are widely used in the manufacture of electronic devices or their components, and are not limited to image sensors or image display devices. For example, in the manufacturing process of semiconductor wafers, film adhesives are used as die adhesion films. Patent Document 1 discloses a sheet adhesive containing a phenoxy resin with a glass transition temperature of 110° C. or higher, a multifunctional epoxy resin, and a photocationic polymerization initiator. In its specific embodiment, as a photocationic polymerization As the initiator, 4-(phenylthio)phenyldiphenylsonium hexafluorophosphate or the like is used. This sheet-shaped adhesive is said to have excellent shape stability under high temperature conditions. Patent Document 2 discloses an adhesive having active energy ray curability, in which the X value calculated from the a ^* value and b ^* value specified in the CIE1976L ^* a ^* b ^* color system of the adhesive is set to a specific range , and set the color difference ΔE ^* _a specified by the above-mentioned color system before and after hardening to a specific range. The adhesive contains a dye whose color disappears due to irradiation of active energy rays and a photoinitiator, and further contains a (meth)acrylate polymer, a cross-linking agent, and an active energy ray curable component. It is thought that this adhesive can easily confirm hardening caused by irradiation of active energy rays. Patent Document 3 discloses an organic electroluminescent element sealing agent that contains 100 parts by mass of a bisphenol-type epoxy resin as a photocationically polymerizable compound and 0.1 to 100 parts by mass of a specific sulfonium borate salt as a photocation. Polymerizing agent. The sealing material is considered to exhibit excellent photohardening properties and is suitable for sealing electroluminescent components. [Prior art documents] [Patent documents]

[Patent Document 1] International Publication No. 2020/196240 [Patent Document 2] Japanese Patent Application Publication No. 2020-26491 [Patent Document 1] Japanese Patent No. 4933751

[Problem to be solved by the invention]

Many functional components have low heat resistance. When manufacturing devices containing components with such low heat resistance, in order to avoid damage to the components, a manufacturing method is adopted without heat treatment. In the manufacture of such devices, energy-beam-hardening film-like adhesives that can be cured in a low-temperature range from normal temperature to near normal temperature are often used as adhesives. However, film adhesives have lower molecular fluidity than liquid adhesives, so the reactivity of the hardened components tends to be poor in the low temperature range. In order to effectively harden the film adhesive in the low temperature range, it is necessary to increase the amount of energy ray irradiation compared to the liquid adhesive. For example, Patent Document 1 discloses in its specific embodiment that in order to harden the sheet-shaped adhesive, ultraviolet (UV) irradiation of 2000 mJ/cm ² is performed, and further heating is performed at 100°C. Furthermore, Patent Document 2 discloses in its specific embodiment that the hardening of the adhesive layer is almost completed by an irradiation dose of 2000 mJ/cm ² . Furthermore, Patent Document 3 discloses in its specific embodiment that in order to harden the sealing material, UV irradiation of 2000 mJ/cm ² and aging heating at 80°C are performed. On the other hand, if the amount of energy ray irradiation increases, even without heating, a heat generation phenomenon will occur as a side reaction accompanying the hardening reaction, and as a result, functional elements may be exposed to high temperatures. In this case, it is easy to cause problems such as poor reliability or reduced transparency caused by the deterioration of the adhesive force of the adhesive itself. Therefore, there is a demand for a highly reactive film-like transparent adhesive that can be hardened with a small amount of energy ray irradiation and whose adhesive strength is not easily reduced at high temperatures. In addition, considering that some devices will be placed in a high-temperature environment during use, or some devices themselves will become high-temperature due to the heat generated from the inside (for example, vehicle-mounted devices, etc.), therefore, it is necessary to improve this From the perspective of reliability of devices under environmental conditions, an adhesive whose adhesive strength is not easily reduced at high temperatures is also required. Generally speaking, fillers are often added to adhesives to improve adhesion. By adding filler materials, the bonding reliability of the adhesive can be improved. However, the addition of filler material will reduce the transparency of the adhesive. Therefore, when a filler material is added, there is a so-called trade-off relationship between the above-mentioned reliability improvement and the transparency of the adhesive. There is a demand for a film-like transparent adhesive that can achieve high bonding reliability even when a filler is added.

An object of the present invention is to provide an energy ray-curable film-like transparent adhesive that can be cured with a small amount of energy ray irradiation to exert sufficient adhesion, has excellent transparency after curing, and is not prone to decrease in adhesion at high temperatures. . Furthermore, an object of the present invention is to provide a device containing the above-mentioned energy ray curable film-like transparent adhesive and a method of manufacturing a device using the above-described energy ray curable film-like transparent adhesive. [Technical means to solve the problem]

The above-mentioned problems of the present invention are solved by the following means. 〔1〕 An energy ray curable film-like transparent adhesive contains: epoxy resin, phenoxy resin, and a photocationic polymerization initiator containing antimony in the anionic part. 〔2〕 The energy ray curable film-like transparent adhesive according to [1], wherein the phenoxy resin has a glass transition temperature of 80 to 120°C. 〔3〕 The energy ray curable film-like transparent adhesive according to [1] or [2], wherein the glass transition temperature of the cured product of the energy ray curable film-like transparent adhesive is 80° C. or higher. 〔4〕 The energy ray curable film-like transparent adhesive according to any one of [1] to [3], wherein the parallel light transmittance of the cured product of the energy ray curable film-like transparent adhesive is 80% or more. . 〔5〕 The energy ray curable film-like transparent adhesive according to any one of [1] to [4], wherein the storage elastic modulus of the cured product of the energy ray curable film-like transparent adhesive at normal temperature is 1.0. GPa or above. 〔6〕 The energy-ray curable film-like transparent adhesive according to any one of [1] to [5], wherein the epoxy resin has a hydrogenated bisphenol structure or a bisphenol structure. 〔7〕 The energy-beam curable film-like transparent adhesive according to any one of [1] to [6], which contains a silane coupling agent. 〔8〕 The energy-beam curable film-like transparent adhesive according to any one of [1] to [7], which contains a hardening retardant. 〔9〕 The energy-beam curable film-like transparent adhesive according to any one of [1] to [8], which contains a filler. 〔10〕 A device including a structure in which constituent members are bonded using the energy-beam curable film-like transparent adhesive according to any one of [1] to [9]. 〔11〕 A method of manufacturing a device, which includes bonding constituent members using the energy-beam curable film-like transparent adhesive according to any one of [1] to [9].

In the present invention, the numerical range represented by "～" means a range including the numerical values written before and after "～" as the lower limit and the upper limit. [Effects of the invention]

The energy ray curable film-like transparent adhesive of the present invention can be cured with a small amount of energy ray irradiation to exert sufficient adhesive force, has high transparency, and the adhesive force is not easily reduced at high temperatures. In addition, even if the energy-beam curable film-like transparent adhesive of the present invention is used as an adhesive for components with low heat resistance, it can suppress damage to the components and further improve the bonding reliability of the obtained device.

[Energy ray curable film-like transparent adhesive] The energy-beam curable film-like transparent adhesive of the present invention (hereinafter, also referred to as the "film-like adhesive of the present invention") contains an epoxy resin, a phenoxy resin, and a photocationic polymerization starter containing antimony in the anionic part. agent. The film-like adhesive of the present invention is in a state before hardening, that is, a B-stage state. It is hardened by energy ray irradiation and exerts adhesive force with the adherend. Therefore, the film-like adhesive agent of the present invention is a film composed of a curable composition. The film-like adhesive of the present invention can be suitably used for bonding or sealing of components of a device. Examples of devices include digital still cameras, digital video cameras, organic EL devices, liquid crystal panel devices, micro-LED devices, smartphones, computers, televisions, etc. The film-like adhesive of the present invention is particularly suitable for components of optical products requiring high transparency (e.g., components of organic EL devices, liquid crystal panels, micro-LED devices, etc.) (e.g., lenses, transparent protective films, glass substrates, and functions described below). It is used for bonding or sealing of sexual components, functional layers, laminates thereof, etc.). Examples of energy rays include light such as ultraviolet (UV) and ionizing radiation such as electron beams. Energy rays are preferably ultraviolet rays. The film adhesive of the present invention does not use a thermal polymerization initiator.

Each component contained in the film adhesive agent of this invention is demonstrated.

(epoxy resin) The film adhesive of the present invention contains at least one epoxy resin. The epoxy resin only needs to be a resin having an epoxy group, and epoxy resins that can be used as adhesives can be widely used. Epoxy resin is one in which epoxy groups react with reactive groups of other components or epoxy groups ring-opening polymerize with each other to form a cross-linked structure in the resin composition. In the present invention, the term epoxy resin refers to one having an epoxy equivalent of 3000 g/eq or less. Furthermore, in the present invention, the so-called epoxy equivalent refers to the number of grams (g/eq) of the resin containing 1 gram equivalent of epoxy groups. The epoxy equivalent of the epoxy resin is preferably 100-3000 g/eq, more preferably 180-1500 g/eq. When the epoxy resin has an alicyclic structure, the epoxy equivalent is preferably larger. For example, it is preferably 200 g/eq or more, more preferably 200 to 3000 g/eq, and still more preferably 200 to 1500 g/eq. On the contrary, when the epoxy resin does not have an alicyclic structure, the epoxy equivalent can be further reduced. For example, it is preferably less than 200 g/eq, more preferably 100 to 195 g/eq, still more preferably 120 to 195 g/eq, still more preferably 130 to 195 g/eq. From the viewpoint of improving the flexibility of the cured product of the film adhesive of the present invention, an epoxy resin having an alicyclic structure and a small epoxy equivalent (for example, an epoxy equivalent of 500 g/eq or less) may be used in combination. Epoxy resin, preferably an epoxy resin with an epoxy equivalent of less than 300 g/eq), and an epoxy resin with an alicyclic structure and a large epoxy equivalent (for example, an epoxy equivalent of 600 to 1300 g/eq The epoxy resin is preferably an epoxy resin with an epoxy equivalent of 900 to 1300 g/eq).

As the skeleton of epoxy resin, there can be listed: phenolic novolak type, o-cresol novolak type, cresol novolac type, dicyclopentadiene type, biphenyl type, bisphenol type, tribisphenol type, Type, naphthol type, naphthodiphenol type, triphenylmethane type, tetraphenyl type, bisphenol A type, bisphenol F type, bisphenol AD type, bisphenol S type, trimethylolmethane type, etc. Among them, triphenylmethane type, bisphenol A type, cresol novolac type, and o-cresol novolak type are preferred from the viewpoint that the crystallinity of the resin is low and a film-like adhesive with good appearance can be obtained. . One type of these may be used alone, or two or more types may be used in combination. The above-mentioned epoxy resin is preferably an epoxy resin having a bisphenol structure. Moreover, the above-mentioned epoxy resin is preferably an epoxy resin having an alicyclic structure, further preferably a hydrogenated bisphenol type epoxy resin (an epoxy resin having a hydrogenated bisphenol structure), and further preferably a hydrogenated bisphenol A type. Epoxy resin. From the viewpoint of reducing yellowing of the cured product of the film adhesive of the present invention and improving transparency, it is preferable to use an epoxy resin having an alicyclic structure, and more preferably to use an epoxy resin having a hydrogenated bisphenol structure. .

The epoxy resin can be either liquid epoxy resin or solid epoxy resin. From the viewpoint of suppressing stickiness and improving handleability, it is preferable to use solid epoxy resin alone or to use solid epoxy resin and liquid epoxy resin in combination.

The weight average molecular weight of the epoxy resin is preferably 100-3000, more preferably 200-1500. The weight average molecular weight is a value analyzed by GPC (Gel Permeation Chromatography).

In the solid components (components other than the solvent) of the film adhesive of the present invention, the content of the epoxy resin is preferably 10 to 80 mass %, more preferably 25 to 80 mass %, and still more preferably 30 to 80 mass %. Mass % is more preferably 40 to 75 mass %, further preferably 50 to 75 mass %, and most preferably 60 to 70 mass %.

(Phenoxy resin) The film adhesive of the present invention contains at least one phenoxy resin. Phenoxy resin is a component that suppresses the tackiness of the film at normal temperature (23°C) and imparts film-forming properties (film-forming properties) when forming a film-like adhesive. In addition, in the present invention, the so-called phenoxy resin refers to one whose epoxy equivalent (the mass of the resin corresponding to one equivalent of epoxy group) exceeds 3000 g/eq. That is, resins with an epoxy equivalent of 3000 g/eq or less are classified as epoxy resins even if they have the structure of a phenoxy resin.

Phenoxy resins are conventionally available. For example, it can be obtained by the reaction of a bisphenol or biphenol compound and an epihalohydrin such as epichlorohydrin, or the reaction of a liquid epoxy resin and a bisphenol or biphenol compound.

The glass transition temperature (Tg) of the phenoxy resin is preferably 160°C or lower, more preferably 120°C or lower, further preferably less than 110°C, further preferably 100°C or less, particularly preferably 90°C or less. The Tg of the phenoxy resin is preferably 0°C or higher, 10°C or higher, 20°C or higher, and may be 30°C or higher, 40°C or higher, or 50°C or higher. , may be set to 60°C or above, may be set to 70°C or above, and is preferably 80°C or above. The Tg of the phenoxy resin is preferably 0 to 160°C, 10 to 125°C, 30 to 120°C, 50 to 120°C, and 70 to 120°C. , is also preferably 80 to 120°C, is also preferably above 80°C and less than 110°C, and is also preferably 80 to 100°C. From the viewpoint of increasing the storage elastic modulus of the cured product of the film adhesive of the present invention at normal temperature (23°C), the Tg of the phenoxy resin is preferably 80°C or more. From the viewpoint of further improving the transparency of the cured product of the film adhesive of the present invention, the Tg of the phenoxy resin is preferably 10 to 120°C, more preferably 80 to 120°C, and further preferably 80°C. Above and below 110°C, preferably 80 to 100°C. The Tg of the above-mentioned phenoxy resin is the peak temperature of tan δ in dynamic viscoelasticity measurement. Specifically, Tg can be determined as follows. The solution in which the phenoxy resin is dissolved is applied to the release film and heated and dried to form a film (polymer film) composed of the phenoxy resin on the release film. The release film was peeled off and removed from the polymer film, and a dynamic viscoelasticity measuring device (trade name: Rheogel-E4000F, manufactured by UBM Company) was used to measure the temperature in the range of 20 to 300°C, the temperature rise rate of 5°C/min, and The polymer film was measured at a frequency of 1 Hz. Let the obtained tan δ peak top temperature (the temperature at which tan δ shows maximum) be Tg.

As the above-mentioned phenoxy resin, the weight average molecular weight is usually 10,000 or more. Although the upper limit is not particularly limited, it is practically 5,000,000 or less. The weight average molecular weight of the above-mentioned phenoxy resin is determined by polystyrene conversion using GPC (Gel Permeation Chromatography).

If attention is paid to the skeleton of the phenoxy resin, in the present invention, bisphenol A type phenoxy resin, a phenoxy resin containing a biphenyl skeleton and a cyclohexane skeleton, or bisphenol F+1,6 can be preferably used. -Hexanediol diglycidyl ether type phenoxy resin.

In the film adhesive agent of the present invention, the content of the phenoxy resin may be, for example, 30 to 500 parts by mass, 30 to 400 parts by mass, or 30 parts by mass relative to 100 parts by mass of the epoxy resin. ~300 parts by mass, may be 40-250 parts by mass, may be 40-120 parts by mass, and is preferably 40-80 parts by mass.

(Photocationic polymerization initiator) The film-like adhesive agent of the present invention contains a photocationic polymerization initiator containing antimony in the anionic site (hereinafter, also referred to as "photocationic polymerization initiator"). The term "containing antimony at the anion site" means having an anion containing an antimony atom at the anion site. The photocationic polymerization initiator is preferably an onium salt having the above-mentioned anionic moiety and cationic moiety, and is more preferably an aromatic onium salt. The anionic part of the photocationic polymerization initiator only needs to be an anion containing an antimony atom, preferably SbF ₄ ^- and SbF ₆ ^- , more preferably SbF ₆ ^- . The cationic site of the photocationic polymerization initiator is not particularly limited, but is preferably a sulfonium compound ion, a iodonium compound ion, an ammonium compound ion, a phosphonium compound ion, a pyridinium compound ion, etc., and more preferably a sulfonium compound ion or a iodonium compound ion. The cationic moiety is not particularly limited as long as it has a structure that functions as a photocationic polymerization initiator. From the viewpoint of light absorption, it is preferred to have an aromatic group. As the aromatic group, an aryl group is preferred, and a phenyl group is more preferred. If the photocationic polymerization initiator is classified according to the type of cationic site, it may also be called a sulfonium salt-based compound, a iodonium salt-based compound, an ammonium salt-based compound, a phosphonium salt-based compound, or a pyridinium salt-based compound. One type of these may be used alone, or two or more types may be used in combination. The photocationic polymerization initiator is preferably a UV cationic polymerization initiator.

In the film adhesive agent of the present invention, the content of the photocationic polymerization initiator may be 0.5 to 30 parts by mass, or 1 to 20 parts by mass, based on 100 parts by mass of the epoxy resin. 1 to 15 parts by mass, preferably 2 to 10 parts by mass, and preferably 2 to 8 parts by mass.

(Additive) The film adhesive of the present invention may also contain a silane coupling agent as an additive. By using a silane coupling agent, the adhesion with the adherend can be further improved, and as a result, the adhesion reliability can be improved. The silane coupling agent is one in which at least one hydrolyzable group such as an alkoxy group or an aryloxy group is bonded to a silicon atom. In addition, an alkyl group, an alkenyl group, or an aryl group may be bonded thereto. The alkyl group is preferably substituted by an amine group, an alkoxy group, an epoxy group or a (meth)acryloxy group, and more preferably an amine group (preferably an aniline group) or an alkoxy group (preferably a cycloalkyl group). Oxypropoxy), (meth)acryloxy substituted ones. Examples of silane coupling agents include 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-glycidoxypropyltrimethoxysilane. Ethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, dimethyldimethoxysilane, dimethyl diethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxy Silane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethyl Oxysilane, 3-methacryloxypropyltriethoxysilane, etc.

When the film adhesive of the present invention contains a silane coupling agent, the content of the silane coupling agent may be 0.1 to 20 parts by mass, or 0.5 to 10 parts by mass relative to 100 parts by mass of the epoxy resin. It can be 1 to 7 parts by mass, preferably 1 to 5 parts by mass, and preferably 1 to 3 parts by mass.

The film adhesive of the present invention may also contain a hardening retardant as an additive. By using a hardening retardant, the adhesion to the adherend is improved and the adhesion force is improved. As the hardening retardant, those commonly used in adhesives can be used. Examples of the hardening retardant include polyether compounds and the like. Examples of the polyether compound include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, calixarene, and crown ether compounds. Among them, crown ether compounds are more suitable. Examples of crown ethers include 18-crown-6-ether, 15-crown-5-ether, and the like.

When the film adhesive of the present invention contains a hardening retardant, the content of the hardening retardant may be 0.01 to 20 parts by mass, or 0.1 to 10 parts by mass relative to 100 parts by mass of the epoxy resin. It can be 0.1 to 8 parts by mass, preferably 0.1 to 5 parts by mass, and preferably 0.1 to 3 parts by mass.

The film adhesive of the present invention may also contain filler materials. That is, the film-like adhesive agent of the present invention may be in a form containing a filler, or may be in a form that does not contain a filler. However, the film-like adhesive of the present invention exhibits appropriate adhesive force even if it does not contain a filler material. The filler material is preferably an inorganic filler material. Examples of inorganic fillers include silica, clay, gypsum, calcium carbonate, barium sulfate, alumina, beryllium oxide, magnesium oxide, silicon carbide, silicon nitride, aluminum nitride, boron nitride, etc. Ceramics; aluminum, copper, silver, gold, nickel, chromium, lead, tin, zinc, palladium, solder and other metals or alloys; carbon nanotubes, graphene and other carbons and other inorganic powders. The inorganic filler material can also undergo surface treatment or surface modification. Examples of agents used for such surface treatment or surface modification include: silane coupling agent, phosphoric acid or phosphoric acid compound, surfactant, etc. Examples of the shape of the inorganic filler include flakes, needles, filaments, spheres, and scales. From the viewpoint of high filling and fluidity, spherical particles are preferred.

When the film-like adhesive of the present invention contains a filler, the content of the filler in the film-like adhesive is preferably 70 mass % or less, more preferably 60 mass % in the solid content of the film-like adhesive. % or less, preferably 50 mass% or less, and preferably 40 mass% or less. When the film-like adhesive of the present invention contains a filler, the content of the filler in the film-like adhesive may be 1% by mass or more, may be 2% by mass or more, and is preferably 4%. Quality% or more. When the film-like adhesive of the present invention contains a filler, the content of the filler in the film-like adhesive may be 71 to 70% by mass in the solid content of the film-like adhesive, or may be 71% to 70% by mass. It can be 2-60 mass %, it can also be 4-50 mass %, it can also be 4-40 mass %, and it is also preferable that it is 10-30 mass %.

The film adhesive of the present invention may further contain organic solvents, ion-trapping agents, hardening catalysts, viscosity adjusters, antioxidants, flame retardants, colorants, etc. For example, other additives of International Publication No. 2017/158994 may be included.

The total proportion of each content of the epoxy resin, phenoxy resin, and photocationic polymerization initiator in the film adhesive of the present invention can be, for example, 30 mass% or more, preferably 40 mass% or more. Furthermore, it is more preferable that it is 50 mass % or more. This ratio may be 60 mass% or more, 70 mass% or more, 80 mass% or more, or 90 mass% or more.

Here, in the present invention, the “film” refers to a thin film with a thickness of 200 μm or less. The shape, size, etc. are not particularly limited and can be appropriately adjusted according to the usage. The thickness of the film-like adhesive of the present invention and the hardened material obtained by hardening the film-like adhesive is usually 1 to 100 μm, preferably 2 to 80 μm, and still more preferably 5 to 50 μm. Thickness can be measured by contact or linear gauge (desktop contact thickness measuring device).

The glass transition temperature (Tg) of the hardened material of the film adhesive of the present invention is preferably 64°C or higher, more preferably 80°C or higher. The Tg of the hardened material of the film-like adhesive is the peak temperature of tan δ in dynamic viscoelasticity measurement. Specifically, Tg can be determined as follows. Use a laminating machine to laminate the film adhesive at 70°C until the thickness becomes 0.3 mm. Use a mercury lamp to irradiate the film with ultraviolet rays at 23°C and 500 mJ/ ^cm2 to cause a hardening reaction. The obtained hardened sample was cut into a width of 5 mm to prepare a measurement sample. Using the dynamic viscoelasticity measuring device RSAIII (manufactured by TA Instruments), the distance between the chucks is 20 mm, the frequency is 10 Hz, the measurement temperature range is -40°C ~ 250°C, and the temperature rise rate is 5°C/min. Measure the sample for measurement. The obtained tan δ peak temperature (the temperature at which tan δ shows maximum) was defined as the Tg of the cured product of the film adhesive. Here, the Tg of the cured product of the film adhesive of the present invention is X°C. When the Tg of the cured product is two or more, it means that the Tg on the lowest temperature side is X°C. Therefore, for example, when the Tg of the cured product of the film adhesive of the present invention is 80°C or more, when the Tg of the cured product is 2 or more, it means that the Tg on the lowest temperature side is 80°C or more. The Tg of the hardened material of the film adhesive of the present invention is preferably 80°C or higher, more preferably 90°C or higher, and still more preferably 100°C or higher. The Tg of the hardened material of the film adhesive of the present invention is preferably 80 to 150°C, more preferably 80 to 140°C, further preferably 90 to 130°C, further preferably 100 to 130°C. Tg can also be set to 110 to 125°C.

The parallel light transmittance of the cured product of the film-like adhesive of the present invention is preferably 70% or more. In the present invention, the above parallel light transmittance refers to the parallel light transmittance at 400 nm. Film-like adhesives are generally prone to yellowing due to irradiation with energy rays. Therefore, the transparency of the obtained cured product can be evaluated based on the parallel light transmittance at the above wavelength. That is, the parallel light transmittance at 400 nm can be used to represent the parallel light transmittance in the visible light range beyond 400 nm. The parallel light transmittance of the cured product of the film adhesive of the present invention is preferably 80% or more, more preferably 85% or more, and further preferably 90% or more. The practical upper limit of parallel light transmittance is 100%. Therefore, the parallel light transmittance of the cured product of the film-like adhesive of the present invention is preferably 80 to 100%. Parallel light transmittance can be measured using a spectrophotometer. Specifically, the parallel light transmittance of the hardened object is determined as follows. Use a laminating machine to laminate the film adhesive at 70°C until the thickness becomes 0.3 mm, and harden it at 500 mJ/ ^cm2 . The obtained hardened sample was cut into 5 cm squares to prepare measurement samples. Use a spectrophotometer (UV-1800 ultraviolet-visible spectrophotometer manufactured by Shimadzu Corporation) to determine the parallel light transmittance of the sample at a wavelength of 400 nm.

The storage elastic modulus (hereinafter, also referred to as "storage elastic modulus") of the hardened material of the film-like adhesive of the present invention at normal temperature (23°C) is preferably 0.8 GPa or more. The storage elastic modulus of the hardened material is more preferably 1.0 GPa or more, and more preferably 1.2 GPa or more. The storage elastic modulus of the hardened material is preferably 7.0 GPa or less, more preferably 6.0 GPa or less, further preferably 5.5 GPa or less, particularly preferably 5.0 GPa or less. The storage elastic modulus of the above-mentioned hardened material can be set to 0.8 to 7.0 GPa, or 0.8 to 6.0 GPa, preferably 1.0 to 5.5 GPa, preferably 1.0 to 5.0 GPa, and preferably 1.0 to 4.0 GPa, preferably 1.0 to 3.0 GPa. The storage elastic modulus of the above-mentioned hardened material is determined as follows. Use a laminating machine to laminate the film adhesive at 70°C until the thickness becomes 0.3 mm, and harden it at 500 mJ/ ^cm2 . The obtained hardened sample was cut into a width of 5 mm to prepare a measurement sample. The dynamic viscoelasticity measuring device RSAIII (manufactured by TA Instruments) was used to measure the temperature from -40°C to 250°C under the tensile conditions of a distance between clamps of 20 mm and a frequency of 10 Hz, and a temperature rise rate of 5°C/min. ℃ temperature rise, determine the storage elastic modulus of the measured sample at 23 ℃.

The storage elastic modulus of the cured product of the film adhesive of the present invention can be determined by the chemical structure (skeleton, type of functional groups, etc.), molecular weight, epoxy equivalent, and content of the epoxy resin, and the chemistry of the phenoxy resin. Structure (skeleton, types of functional groups, etc.), molecular weight, glass transition temperature, and content, etc., chemical structure (skeleton, types of functional groups, etc.) and content of the photocationic polymerization initiator, filler materials in the adhesive, and The type or content of other additives should be controlled.

The film adhesive of the present invention can be prepared by preparing a composition (varnish) by mixing each component of the film adhesive, and coating the composition on a release film or a required base material, as needed. Dry and obtain on the above-mentioned release film or substrate. The composition (varnish) in which the components of the adhesive layer are mixed usually contains an organic solvent. As the coating method, a known method can be suitably used, and examples thereof include methods using a roller blade coater, a gravure coater, a die coater, a reverse coater, and the like. Drying only needs to be able to remove the organic solvent and form a film-like adhesive without substantially causing a hardening reaction. For example, it can be performed by maintaining the temperature at 80 to 150° C. for 1 to 20 minutes.

From the viewpoint of suppressing the hardening reaction of the film-like adhesive (hardening reaction of the epoxy resin), the film-like adhesive of the present invention is preferably stored in a light-shielded state before use (before the hardening reaction). The temperature conditions during light-shielded storage are not particularly limited, and can be at room temperature or refrigerated.

[Device manufacturing method] The method of manufacturing the device of the present invention is not particularly limited as long as the device is manufactured using the film adhesive of the present invention. One embodiment of the device manufacturing method of the present invention includes using the film adhesive of the present invention to adhere the constituent components. Therefore, the device of the present invention includes a structure in which the constituent members are bonded using the film adhesive of the present invention. The constituent members of the device to which the film-like adhesive of the present invention is applied are not particularly limited, and examples thereof include the above-mentioned functional elements and functional layers, and laminates thereof. One embodiment of the manufacturing method of the device of the present invention includes using the film-like adhesive of the present invention to bond the components, for example, a laminate including functional elements (functional elements and various components arranged on one or both sides thereof). The laminate of functional layers) between each other, between the base material and the laminate including functional elements, between the first base material and the second base material (it can also be on either one of the first and second base materials, or A laminate including functional elements is formed on the side opposite to the adhesive layer of both base materials. Therefore, one embodiment of the method for manufacturing a device of the present invention includes the following steps: arranging the film-like adhesive of the present invention on the surface of one component of the device, and arranging the other component of the device via the film-like adhesive. A component that causes the film-like adhesive to undergo a hardening reaction.

In the device manufacturing method of the present invention, the conditions for the above-mentioned hardening reaction can be appropriately set taking into consideration the type of hardener, the heat resistance of the functional element, and the like. For example, the adhesive layer can be fully hardened by irradiating ultraviolet light of 100 to 1500 mJ/cm ² using a mercury lamp or the like. From the viewpoint of reducing the irradiation dose, the upper limit of the irradiation dose is preferably 700 mJ/cm ² or less, more preferably 600 mJ/cm ² or less. [Example]

The present invention will be described in more detail based on Examples and Comparative Examples, but the present invention is not limited to the forms of the following Examples. In addition, room temperature refers to 23°C, MEK refers to methyl ethyl ketone, PET refers to polyethylene terephthalate, and UV refers to ultraviolet rays. Unless otherwise stated, "%" and "parts" are based on mass.

<Preparation of film adhesive> (Example 1) In a 1000 ml separable flask, ST-3000 (trade name, hydrogenated bisphenol A type liquid epoxy resin) as an epoxy resin was prepared at a temperature of 110°C. Epoxy equivalent: 225 g/eq, manufactured by Nippon Steel Chemical & Material Co., Ltd.) 70 parts by mass, YP-50 as a phenoxy resin (trade name, bisphenol A type phenoxy resin, Tg: 84°C, 30 parts by mass (manufactured by Nippon Steel Chemical & Material Co., Ltd.) and 30 parts by mass of MEK were heated and stirred for 2 hours to obtain a resin varnish. Furthermore, the resin varnish was transferred to an 800 ml planetary mixer, and WPI-116 (trade name, UV cationic polymerization initiator (iodide type, anionic part: SbF ₆ ^- ), FUJIFILM Wako Pure Chemical Co., Ltd. (manufactured by the company) 2 parts by mass as a polymerization initiator, stir and mix at room temperature for 1 hour, and then perform vacuum defoaming to obtain a mixed varnish. Then, the obtained mixed varnish was coated on a 38 μm-thick PET film that had been surface-released and heated and dried at 130°C for 10 minutes to obtain a length of 300 mm, a width of 200 mm, and a thickness of 20 μm. Film-like adhesive with peel-off film.

(Example 2) The phenoxy resin is YX7200B35 (trade name, phenoxy resin containing biphenyl skeleton and cyclohexane skeleton, Tg: 150°C, non-volatile content 35% by mass, epoxy equivalent: 9000 g/eq, Mitsubishi Chemical Co., Ltd.) 86 parts by mass (of which the phenoxy resin (solid content) was 30 parts by mass), a film-like adhesive for a release film was obtained in the same manner as in Example 1.

(Example 3) The epoxy resin was adjusted to 70 parts by mass of 828 (trade name, bisphenol A type epoxy resin, epoxy equivalent: 185 g/eq, manufactured by Nippon Steel Chemical & Material Co., Ltd.). 1 Obtain a film-like adhesive with a release film in the same manner.

(Example 4) Add 1 part by mass of KBM-402 (trade name, silane coupling agent (3-glycidoxypropylmethyldimethoxysilane), manufactured by Shin-Etsu Chemical Industry Co., Ltd.) as an additive to the mixed varnish. Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 1.

(Example 5) A release film was obtained in the same manner as in Example 1, except that 0.1 part by mass of 18-crown-6-ether (trade name, hardening retarder, manufactured by Tokyo Chemical Industry Co., Ltd.) was added to the mixed varnish as an additive. Film adhesive.

(Example 6) The epoxy resin was 50 parts by mass of ST-3000 (trade name, hydrogenated bisphenol A type liquid epoxy resin, epoxy equivalent: 225 g/eq, manufactured by Nippon Steel Chemical & Material Co., Ltd.) and YX8040 (trade name) , hydrogenated bisphenol A type solid epoxy resin, epoxy equivalent: 1200 g/eq, manufactured by Mitsubishi Chemical Co., Ltd.) 20 parts by mass, except that a film with a release film was obtained in the same manner as in Example 1. Adhesive.

(Example 7) 33 parts by mass of YC100C-MLA (trade name, silica filler slurry, solid content: 60%, manufactured by Admatechs Co., Ltd.) (20 parts by mass of silica filler) was added to the mixed varnish as a filler material , Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 1.

(Example 8) The blending amount of the epoxy resin was 50 parts by mass, the blending amount of the phenoxy resin was 50 parts by mass, and the polymerization initiator was CPI-101A (trade name, UV cationic A film-like adhesive with a release film was obtained in the same manner as in Example 1, except for 2 parts by mass of a polymerization initiator (sulfonium salt type, anionic site: SbF ₆ ^- ), manufactured by San-Apro Co., Ltd. .

(Example 9) The polymerization initiator was 2 parts by mass of CPI-101A (trade name, UV cationic polymerization initiator (sulfonium salt type, anionic site: SbF ₆ ^- ), manufactured by San-Apro Co., Ltd.), Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 4.

(Example 10) A film-like adhesive with a release film was obtained in the same manner as in Example 1, except that the blending amount of the epoxy resin was 30 parts by mass and the blending amount of the phenoxy resin was 70 parts by mass. .

(Example 11) The blending amount of the epoxy resin was set to 50 parts by mass, and the phenoxy resin was set to YX7180 (trade name, bisphenol F + 1,6-hexanediol dialpoxypropyl ether type phenoxy resin, Tg: 15 ℃, Mitsubishi Chemical Co., Ltd.) 50 parts by mass, in the same manner as in Example 1, except that a film-like adhesive with a release film was obtained.

(Example 12) The phenoxy resin was 30 parts by mass of YX7180 (trade name, bisphenol F + 1,6-hexanediol diglycidyl ether type phenoxy resin, Tg: 15°C, manufactured by Mitsubishi Chemical Co., Ltd.), except Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 1.

(Example 13) 67 parts by mass of YC100C-MLA (trade name, silica filler slurry, solid content: 60%, manufactured by Admatechs Co., Ltd.) (including 40 parts by mass of silica filler) was added to the mixed varnish as a filling material. Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 1.

(Comparative Example 1) The blending amount of the epoxy resin was set to 40 parts by mass, and phenoxy resin YX7200B35 (trade name, phenoxy resin containing a biphenyl skeleton and a cyclohexane skeleton, Tg: 150°C, no The blending amount of volatile content: 35 mass%, epoxy equivalent: 9000 g/eq, manufactured by Mitsubishi Chemical Co., Ltd.) is 171 parts by mass (of which the phenoxy resin (solid content) is 60 parts by mass), and The polymerization initiator was set to 2 parts by mass of CPI-100P (trade name, UV cationic polymerization initiator (sulfonium salt type, anionic part: PF ₆ ^- ), manufactured by San-Apro Co., Ltd.). In the same manner as Example 2, a film-like adhesive with a release film was obtained.

(Comparative Example 2) The blending amount of the epoxy resin was set to 50 parts by mass, and the phenoxy resin YX7200B35 (trade name, phenoxy resin containing a biphenyl skeleton and a cyclohexane skeleton, Tg: 150°C, not The blending amount of volatile content: 35 mass%, epoxy equivalent: 9000 g/eq, manufactured by Mitsubishi Chemical Co., Ltd.) is 142 parts by mass (of which the phenoxy resin (solid content) is 50 parts by mass), and The polymerization initiator was CPI-200K (trade name, UV cationic polymerization initiator (sulfonium salt type, anionic part: PF ₃ (C ₂ F ₅ ) ₃ ^- ), manufactured by San-Apro Co., Ltd.) 2 parts by mass , Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 2.

(Comparative example 3) A film-like adhesive with a release film was obtained in the same manner as in Comparative Example 1.

(Comparative Example 4) The polymerization initiator was CPI-100P (trade name, UV cationic polymerization initiator (sulfonium salt type, anionic site: PF ₆ ^- ), manufactured by San-Apro Co., Ltd.), 2 parts by mass, Except for this, a film-like adhesive with a release film was obtained in the same manner as in Example 1.

(Comparative Example 5) The polymerization initiator was CPI-200K (trade name, UV cationic polymerization initiator (sulfonium salt type, anionic site: PF ₃ (C ₂ F ₅ ) ₃ ^- ), San-Apro Co., Ltd. company) 2 parts by mass, a film-like adhesive with a release film was obtained in the same manner as in Example 1, except for this.

(Comparative example 6) 50 parts by mass of SG-708-6 (trade name, acrylic resin, Tg: 5°C, manufactured by Nagase ChemteX Co., Ltd.) was used instead of the phenoxy resin, and the polymerization initiator was TPO (trade name, UV radical polymerization The same procedure as Comparative Example 2 was performed except that 2 parts by mass of the starting agent (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide), manufactured by Tokyo Chemical Industry Co., Ltd. A film-like adhesive with a release film is obtained.

(Comparative example 7) A film with a release film was obtained in the same manner as in Comparative Example 6, except that the polymerization initiator was 2 parts by mass of benzophenone (UV radical polymerization initiator, manufactured by Tokyo Chemical Industry Co., Ltd.) Adhesive.

(Comparative Example 8) The polymerization initiator was set to 2 parts by mass of WPI-116 (trade name, UV cationic polymerization initiator (ion salt type, anionic site: SbF ₆ ^- ), manufactured by FUJIFILM Wako Pure Chemical Co., Ltd. , except that a film-like adhesive with a release film was obtained in the same manner as Comparative Example 6.

Table 1 shows the composition of the film adhesives of each Example and Comparative Example.

＜Preparation of hardened objects (hardened samples) and confirmation of the presence of heat＞ The peeling film was peeled off from the film-like adhesive with peeling film obtained in each of the Examples and Comparative Examples, and the film-like adhesive was laminated using a laminating machine at 70°C until the thickness became 0.3 mm to obtain a laminated sample. ℃) The laminated samples were treated with the UV irradiation amounts listed in the "UV irradiation amount" column of the "Harded Sample Production Conditions" in Table 1, and the storage elastic modulus and parallel light transmittance used for the following were obtained. Hardened samples (hardened materials) for evaluation. At this time, the surface temperature of the sample before and after UV irradiation was measured, and the presence or absence of heat generation caused by UV irradiation was also evaluated. The surface temperature was measured using a non-contact surface thermometer (FT3700, manufactured by Hioki Electric Co., Ltd.). The surface temperature after UV irradiation was measured within 5 seconds after UV irradiation. The surface temperature difference before and after UV irradiation (surface temperature after UV irradiation - surface temperature before UV irradiation) is recorded in Table 1.

＜Measurement of storage elastic modulus and glass transition temperature of hardened material＞ As indicators of the cured state of the film adhesive, the storage elastic modulus and glass transition temperature of the cured product of the film adhesive were measured. Cut the hardened sample produced above into a width of 5 mm to prepare a measurement sample. Using a measuring device RSAIII (manufactured by TA Instruments), under the tensile conditions of a distance between the chucks of 20 mm and a frequency of 10 Hz, the temperature rise rate was 5°C/min from -40°C to 250°C. The viscoelastic behavior of each sample was measured when the temperature was raised, and the storage elastic modulus and Tg at 23°C were obtained. Tg is the temperature showing the maximum value of tan δ. When there are two or more maximum values, the temperature showing the maximum value on the low temperature side is set to Tg. The measurement results are shown in Table 1.

＜Measurement of parallel light transmittance＞ The transparency of the cured product of the film adhesive is evaluated based on the transmittance of parallel light with a wavelength of 400 nm. Cut the hardened sample produced above into 5 cm squares to prepare a measurement sample. The parallel light transmittance of each obtained measurement sample was measured using a spectrophotometer (UV-1800 manufactured by Shimadzu Corporation) to determine the parallel light transmittance of a wavelength of 400 nm.

＜Adhesion reliability＞ Using the change rate of the adhesion force (shear strength) of the adherend (glass plate and dummy wafer) that is adhered to the hardened material of the film-form adhesive as an index, the cured state and adhesion force of the film-form adhesive are evaluated. Make an evaluation. 1) Preparation of samples First, a manual laminating machine (trade name: FM-114, manufactured by TECHNOVISION) was used to laminate the film-like adhesive with release film obtained in each example and comparative example at a temperature of 70°C and a pressure of 0.3 MPa. (Before hardening) Thermo-compression bonding to one side of the dummy silicon wafer (size: 8 inches, thickness: 350 μm). Thereafter, after peeling off the release film from the film-like adhesive, use the above-mentioned manual laminating machine to assemble the cutting film and cutting frame (trade name: DTF2-8-1H001, manufactured by DISCO) at room temperature and a pressure of 0.3 MPa. Press-bond to the surface of the film-like adhesive opposite to the above-mentioned dummy silicon wafer. Next, a cutting device (trade name: DFD-6340, DISCO) equipped with a biaxial cutting knife (Z1: NBC-ZH2050 (27HEDD), manufactured by DISCO Corporation/Z2: NBC-ZH127F-SE (BC), manufactured by DISCO Corporation) is used. company), cut (cut) in the thickness direction of the film adhesive from the side of the dummy silicon wafer to a depth of 2 mm × 2 mm to reach the entire thickness of the film adhesive. A dummy wafer with adhesive attached is obtained on the dicing film. Then, use a die bonding machine (trade name: DB-800, manufactured by Hitachi High-Technologies Co., Ltd.) to pick up the dummy wafer with the above-mentioned adhesive from the cutting film, and place it at 80°C, a pressure of 0.1 MPa (a load of 400 gf), and a time Under the condition of 1.0 seconds, the adhesive side of the dummy chip with the above-mentioned adhesive and the glass plate as the substrate substrate (thickness 700 μm, length 10 mm × width 10 mm) are bonded to the center of the glass plate and hot pressed catch. Then, a UV irradiation machine is used to irradiate UV from the glass plate side with a specific UV irradiation amount (recorded in the "UV irradiation amount" column of "Reliability Evaluation" in the table) to harden the adhesive. In this way, a test piece having a dummy wafer, a hardened material of the adhesive, and a glass plate was obtained. 2) Determination of shear strength The shear strength between the hardened material of the adhesive and the glass plate of the test piece obtained above was measured using a universal bonding strength testing machine (trade name: 4000PXY series, manufactured by Nordson Advanced Technology). The test conditions were set to a measurement speed of 100 μm/s and a measurement height of 740 μm, and the shear strength when the dummy wafer in the test piece was pushed out horizontally with respect to the test piece was measured. The above-mentioned shear strength was measured at two measurement temperatures (normal temperature (23°C) and high temperature (100°C)), the change rate of the shear strength was determined, and the evaluation was carried out according to the following evaluation standards. The measurement of the shear strength was performed after each of the adherends adhered via the hardened product of the film-like adhesive was stored at the above-mentioned measurement temperature for 1 minute. An evaluation of A or above was considered acceptable. Furthermore, each of the film adhesives of Examples 1 to 13 showed sufficiently high shear strength immediately after curing by UV irradiation. The rate of change of shear strength = {(shear strength at normal temperature - shear strength at high temperature)/shear strength at normal temperature} × 100 [%] -Evaluation criteria- AA: The change rate of shear strength does not reach 5% A: The change rate of shear strength is more than 5% and less than 10% B: The change rate of shear strength is more than 10% and less than 40% C: The change rate of shear strength is more than 40%

[Table 1-1] Example 1 2 3 4 5 6 7 8 9 10 11 12 13 Epoxy resin ST-3000 (hydrogenated bisphenol A liquid epoxy resin, 225 g/eq) 70 70 70 70 50 70 50 70 30 50 70 70 YX8040 (hydrogenated bisphenol A solid epoxy resin, 1200 g/eq) 20 828 (bisphenol A liquid epoxy resin, 185 g/eq) 70 Phenoxy resin YP-50 (phenoxy resin, Tg is 84℃) 30 30 30 30 30 30 50 30 70 30 YX7200B35 (phenoxy resin, Tg is 150℃) 30 YX7180 (phenoxy resin, Tg is 15℃) 50 30 acrylic resin SG-708-6 (acrylic resin, Tg is 5℃) polymerization initiator WPI-116 (anionic part: SbF ₆ ^- ) 2 2 2 2 2 2 2 2 2 2 2 CPI-101A (anionic part: SbF ₆ ^- ) 2 2 CPI-100P (anionic part: PF ₆ ^- ) CPI-200K (Anion part: PF ₃ (C ₂ F ₅ ) ₃ ^- ) TPO Benzophenone additives KBM-402 (silane coupling agent) 1 1 18-crown-6-ether (hardening retardant) 0.1 Filler YC100C-MLA (silica filler) 20 40 Hardened sample preparation conditions Thickness of laminated sample [mm] 300 300 300 300 300 300 300 300 300 300 300 300 300 UV irradiation dose [mJ/cm ² ] 500 500 500 500 500 500 500 500 500 500 500 500 500 Surface temperature difference of the sample before and after UV irradiation [℃] 0 0 0 0 0 0 0 0 0 0 0 0 0 Storage elastic modulus evaluation Tg of hardened material [℃] 120 125 130 118 120 110 123 103 115 100 64 90 130 Storage elastic modulus of hardened material [GPa] 2.0 3.0 3.2 1.8 1.7 1.5 5.4 1.2 1.7 1.0 0.8 0.9 7.0 Transparency evaluation Parallel light transmittance of hardened material@400 nm[%] 95 80 87 92 92 93 83 95 93 94 93 94 70 Reliability evaluation UV irradiation dose [mJ/cm ² ] 500 500 500 500 500 500 500 500 500 500 500 500 500 Reliability evaluation results A A A AA AA A AA A A A A A AA

[Table 1-2] Comparative example 1 2 3 4 5 6 7 8 Epoxy resin ST-3000 (hydrogenated bisphenol A liquid epoxy resin, 225 g/eq) 40 50 40 70 70 50 50 50 YX8040 (hydrogenated bisphenol A solid epoxy resin, 1200 g/eq) 828 (bisphenol A liquid epoxy resin, 185 g/eq) Phenoxy resin YP-50 (phenoxy resin, Tg is 84℃) 30 30 YX7200B35 (phenoxy resin, Tg is 150℃) 60 50 60 YX7180 (phenoxy resin, Tg is 15℃) acrylic resin SG-708-6 (acrylic resin, Tg is 5℃) 50 50 50 polymerization initiator WPI-116 (anionic part: SbF ₆ ^- ) 2 CPI-101A (anionic part: SbF ₆ ^- ) CPI-100P (anionic part: PF ₆ ^- ) 2 2 2 CPI-200K (Anion part: PF ₃ (C ₂ F ₅ ) ₃ ^- ) 2 2 TPO 2 Benzophenone 2 additives KBM-402 (silane coupling agent) 18-crown-6-ether (hardening retardant) Filler YC100C-MLA (silica filler) Hardened sample preparation conditions Thickness of laminated sample [mm] 300 300 300 300 300 300 300 300 UV irradiation dose [mJ/cm ² ] 500 500 2000 500 500 500 500 500 Surface temperature difference of the sample before and after UV irradiation [℃] 0 0 45 0 0 0 0 0 Storage elastic modulus evaluation Tg of hardened material [℃] 65 62 130 57 56 5 5 5 Storage elastic modulus of hardened material [GPa] 0.6 0.5 1.8 0.4 0.3 0.3 0.3 0.4 Transparency evaluation Parallel light transmittance of hardened material@400 nm[%] 65 67 30 70 72 10 13 15 Reliability evaluation UV irradiation dose [mJ/cm ² ] 500 500 2000 500 500 500 500 500 Reliability evaluation results B B A B B C C C

In the above table, the blending amount of each component of the adhesive is expressed in parts by mass. Empty columns indicate that the ingredient is not included.

As shown in the above table, when using a photocationic polymerization initiator that does not contain an antimony atom in the anionic site or a photoradical polymerization initiator as the polymerization initiator, if it is less than 500 mJ/cm ² If the amount of UV irradiation is too high, the hardening will be poor, resulting in at least one of the storage elastic modulus and Tg being low, and the subsequent reliability will be poor (Comparative Examples 1 to 2, 4 to 5). Furthermore, the parallel light transmittances of Comparative Examples 1 and 2 are also poor. In addition, if the normal UV irradiation dose is 2000 mJ/ ^cm2 , although the storage elastic modulus and Tg become higher, and the reliability is improved, there is heat generation, and the parallel light transmittance becomes worse. Results (Comparative Example 3). It is believed that the reason for the low transmittance of parallel light is yellowing caused by heat. If acrylic resin is used instead of phenoxy resin, regardless of the type of polymerization initiator, under a small UV irradiation dose of 500 mJ/ ^cm2 , the storage elastic modulus, bonding reliability, and transparency will be poor. The results (Comparative Examples 6 to 8). It is considered that Comparative Examples 6 to 8 produced white turbidity and the low compatibility between the acrylic resin and the epoxy resin resulted in poor transparency. In contrast, the film adhesives of Examples 1 to 13 that meet the requirements of the present invention have high storage elastic modulus and Tg even when the UV irradiation dose is 500 mJ/cm ² , and exhibit excellent adhesion. Reliability and parallel light penetration. It is found that the film adhesive of the present invention can be fully cured with a small amount of irradiation, and has excellent adhesive strength, transparency, and adhesive reliability at high temperatures. Furthermore, it was found that by using the film adhesive of the present invention for manufacturing devices, the reliability of the devices can be improved. Moreover, it was found that if a phenoxy resin having a Tg of 120° C. or less is used as the phenoxy resin, the transparency can be further improved (comparison between Example 1 and Example 2). It was found that if an epoxy resin having a hydrogenated bisphenol structure is used as the epoxy resin, the transparency can be further improved (comparison between Example 1 and Example 3). It can be seen that if a phenoxy resin with a Tg of 80°C or higher is used as the phenoxy resin, the adhesive force of the cured product can be further improved. Specifically, the Tg or storage elastic modulus of the cured product can be further increased, which contributes to the adhesion. Increase in force (comparison between Example 1 and Examples 11 and 12). It is found that if the content of the filler material is reduced to about 20% by mass of the solid content of the film adhesive, the parallel light transmittance can be more reliably increased to more than 80% (Comparison between Example 7 and Example 13 ).

Although the present invention and its embodiments have been described, unless otherwise specified, the present invention is not limited to any details of the description, but should be broad in a manner that does not violate the spirit and scope of the invention as shown in the appended claims. explain.

This application claims priority based on Japanese Patent Application No. 2022-105913 filed in Japan on June 30, 2022, the contents of which are incorporated herein by reference as a part of the description of this specification.

1: Film adhesive 2: Base material (support base material)

[Fig. 1] is a cross-sectional view schematically showing the structure of the film-like adhesive agent with a release film prepared in the Example.

1: Film adhesive

2: Base material (support base material)

Claims (11)

An energy ray curable film-like transparent adhesive contains: epoxy resin, phenoxy resin, and a photocationic polymerization initiator containing antimony in the anionic part. The energy ray curable film-like transparent adhesive according to claim 1, wherein the glass transition temperature of the phenoxy resin is 80 to 120°C. An energy ray curable film-like transparent adhesive according to claim 1, wherein the glass transition temperature of the cured product of the energy ray curable film-like transparent adhesive is 80° C. or higher. An energy ray curable film-like transparent adhesive according to claim 1, wherein the parallel light transmittance of the cured product of the energy ray curable film-like transparent adhesive is above 80%. The energy ray curable film-like transparent adhesive of claim 1, wherein the storage elastic modulus of the cured product of the energy ray-curable film-like transparent adhesive at room temperature is 1.0 GPa or more. The energy ray curable film-like transparent adhesive of claim 1, wherein the epoxy resin has a hydrogenated bisphenol structure or a bisphenol structure. The energy ray curable film-like transparent adhesive of claim 1 includes a silane coupling agent. The energy ray curable film-like transparent adhesive according to claim 1, which contains a hardening retardant. The energy ray curable film-like transparent adhesive of claim 1 includes a filling material. A device including a structure in which constituent members are bonded using the energy-beam curable film-like transparent adhesive according to any one of claims 1 to 9. A method of manufacturing a device, which includes using the energy ray curable film-like transparent adhesive according to any one of claims 1 to 9 to adhere constituent members.