TWI738641B - Manufacturing method of package - Google Patents

Abstract

The present invention provides a manufacturing method, which is a manufacturing method of a package body for encapsulating an organic EL element on a substrate with a resin composition layer, and includes the following steps: (1) a support, a resin composition layer and a protective film (cover film) The encapsulation sheet laminated in this order, the step of drying with a near-infrared to mid-infrared dryer without peeling off the protective film, and (2) After peeling the protective film from the dried encapsulating sheet, use the resin of the encapsulating sheet The composition layer encapsulates the organic EL device.

Description

Manufacturing method of package

The present invention relates to a method for manufacturing a package (especially an organic EL device) formed by encapsulating an organic EL (Electroluminescence) element on a substrate with a resin composition layer. In addition, the present invention relates to a method of packaging organic EL devices on a substrate.

Organic EL devices are light-emitting devices that use organic substances in light-emitting materials. Because they can achieve high-brightness light emission with low voltage, they have attracted attention in recent years. However, organic EL elements have extremely weak resistance to moisture, and have the problems of reduced brightness due to moisture, no light emission, separation of the interface between the electrode and the light-emitting layer, metal oxidation and high resistance. Therefore, in order to shield the inside of the element from moisture in the outside air, for example, a resin composition layer is formed so as to cover the entire surface of the light-emitting layer formed on the substrate to encapsulate the organic EL element (for example, Patent Documents 1 to 3).

[Prior technical literature] 〔Patent Documents〕

[Patent Document 1] International Publication No. 2010/084938

[Patent Document 2] International Publication No. 2010/084939

[Patent Document 3] International Publication No. 2011/016408

The small amount of moisture present in the sheet used to encapsulate the organic EL device by forming the resin composition layer on the support (hereinafter sometimes referred to as the "encapsulation sheet") may also adversely affect the organic EL device. Therefore, the packaging sheet is desirably transported and stored in a dry state. However, in this case, it is also difficult to completely prevent the intrusion of moisture, and even a small amount of moisture ingress becomes a problem.

Before encapsulating the organic EL element, it is considered to dry the encapsulation sheet, but when the encapsulation sheet is heated at an excessively high temperature for drying, the encapsulation sheet (especially its resin composition) is denatured (e.g., cured) Bad. On the other hand, there is a problem of time-consuming drying in low-temperature vacuum drying.

In addition, the resin composition layer of the encapsulation sheet used before encapsulation is generally protected by a protective film. Regarding the encapsulation sheet, it is considered that moisture is mainly contained in the resin composition layer, and the drying of the resin composition layer of the encapsulation sheet is effective after peeling off the protective film. However, when drying after peeling off the protective film, dirt or the like may adhere to the surface of the resin composition layer during drying, which may adversely affect the organic EL element.

The present invention was completed in view of the above-mentioned circumstances, and its object is to provide a support body, a resin composition layer, and a protective film (cover film) The packaging sheet laminated in this order does not peel off the protective film, but is a method of manufacturing the packaging body of the organic EL device in the step of effectively drying the packaging sheet.

As a result of active review, the inventors found that when the organic EL device is encapsulated with a packaging sheet to produce a package, the trace moisture contained in the packaging sheet may have an adverse effect on the organic EL device. The moisture contained in it is reduced to below a certain value, which can significantly improve the life of the organic EL device, and by introducing a drying step from near infrared to mid-infrared dryer before the packaging step, it can be dried effectively even if the protective film is not peeled off The encapsulation sheet removes moisture. The present invention based on this knowledge is as follows.

[1] A manufacturing method, which is a manufacturing method of a package body that encapsulates an organic EL element on a substrate with a resin composition layer, and includes the following steps: (1) The support, the resin composition layer, and the protective film are arranged accordingly The encapsulation sheet is laminated in order, and the protective film is dried by a near-infrared to mid-infrared dryer without peeling off the protective film. (2) After the protective film is peeled off from the dried encapsulation sheet, it is encapsulated with the resin composition layer of the encapsulation sheet Steps for organic EL devices.

[2] The manufacturing method of [1] above, wherein step (2) is performed in the same manufacturing line as step (1).

[3] The manufacturing method as described in [1] or [2], wherein the following step (1) Go to step (2).

[4] The manufacturing method according to any one of [1] to [3] above, wherein the time from drying in step (1) to before packaging in step (2) is 1 to 60 minutes.

[5] The manufacturing method according to any one of [1] to [3] above, wherein the time from drying in step (1) to before packaging in step (2) is 1 to 30 minutes.

[6] The manufacturing method according to any one of [1] to [3] above, wherein the time from drying in step (1) to before packaging in step (2) is 1 to 15 minutes.

[7] The manufacturing method of any one of [1] to [3] above, wherein the time from drying in step (1) to before packaging in step (2) is 1 to 10 minutes.

[8] The manufacturing method according to any one of [1] to [7] above, wherein the peak wavelength of the near-infrared to mid-infrared irradiated from the near-infrared to mid-infrared dryer is in the range of 1.0 to 4.0 μm.

[9] The manufacturing method according to any one of [1] to [7] above, wherein the peak wavelength of the near-infrared to mid-infrared irradiated from the near-infrared to mid-infrared dryer is in the range of 1.0 to 3.5 μm.

[10] The manufacturing method according to any one of [1] to [7] above, wherein the peak wavelength of the near-infrared to mid-infrared irradiated from the near-infrared to mid-infrared dryer is in the range of 1.25 to 3.5 μm.

[11] The manufacturing method as described in any one of [1] to [7] above, wherein the peak from near infrared to mid-infrared irradiated from the near-infrared to mid-infrared dryer The value wavelength is within the range of 1.5~3.5μm.

[12] The manufacturing method as described in any one of [1] to [11], wherein the drying temperature of the near-infrared to mid-infrared dryer is 60-160°C, and the drying time is 0.5-60 minutes.

[13] The manufacturing method of [12] above, wherein the drying temperature of the near-infrared to mid-infrared dryer is 60~140°C.

[14] The manufacturing method of [12] above, wherein the drying temperature of the near-infrared to mid-infrared dryer is 60~130°C.

[15] The manufacturing method of [12] above, wherein the drying temperature of the near-infrared to mid-infrared dryer is 80~130°C.

[16] The manufacturing method as described in [12] above, wherein the drying temperature of the near-infrared to mid-infrared dryer is 90~130°C.

[17] The manufacturing method of any one of [12] to [16] above, wherein the drying time of the near-infrared to mid-infrared dryer is 1 to 30 minutes.

[18] The manufacturing method of any one of [12] to [16] above, wherein the drying time of the near infrared to mid infrared dryer is 5 to 30 minutes.

[19] The manufacturing method of any one of [12] to [16] above, wherein the drying time of the near-infrared to mid-infrared dryer is 5-15 minutes.

[20] The manufacturing method according to any one of [1] to [19] above, wherein the moisture content of the packaging sheet after step (1) is 500 ppm by weight or less.

[21] The manufacturing method according to any one of [1] to [19], wherein the moisture content of the packaging sheet after step (1) is 400 ppm by weight or less.

[22] The manufacturing method according to any one of [1] to [19], wherein the moisture content of the packaging sheet after step (1) is 300 ppm by weight or less.

[23] The manufacturing method of any one of [1] to [19] above, wherein the moisture content of the packaging sheet after step (1) is 250 ppm by weight or less.

[24] The manufacturing method of any one of [1] to [19] above, wherein the moisture content of the packaging sheet after step (1) is 200 ppm by weight or less.

[25] The manufacturing method of any one of [1] to [19] above, wherein the moisture content of the resin composition layer after step (1) is 2000 ppm by weight or less.

[26] The production method according to any one of [1] to [19], wherein the moisture content of the resin composition layer after step (1) is 1800 ppm by weight or less.

[27] The production method as described in any one of [1] to [19], wherein the moisture content of the resin composition layer after step (1) is 1600 ppm by weight or less.

[28] The production method according to any one of [1] to [19], wherein the moisture content of the resin composition layer after step (1) is 1400 ppm by weight or less.

[29] The manufacturing method of any one of [1] to [19] above, wherein the moisture content of the resin composition layer after step (1) is 1200 ppm by weight or less.

[30] The production method according to any one of [1] to [19] above, wherein the moisture content of the resin composition layer after step (1) is 1000 wtppm or less.

[31] The production method of any one of [1] to [19] above, wherein the moisture content of the resin composition layer after step (1) is 850 wtppm or less.

[32] The manufacturing method of any one of [1] to [31] above, wherein the drying with a near-infrared to mid-infrared dryer is performed under dry air or dry inert gas atmosphere.

[33] The manufacturing method as described in [32] above, wherein the amount of water vapor contained in the dry air or dry inert gas is 0 to 500 ppm.

[34] The manufacturing method of [32] above, wherein the amount of water vapor contained in the dry air or dry inert gas is 0 to 250 ppm.

[35] The manufacturing method as described in [32], wherein the amount of water vapor contained in the dry air or dry inert gas is 0-100 ppm.

[36] The manufacturing method as described in [32], wherein the amount of water vapor contained in the dry air or dry inert gas is 0-50 ppm.

[37] The manufacturing method of the aforementioned [32], wherein the amount of water vapor contained in the dry air or dry inert gas is 0 to 30 ppm.

[38] The manufacturing method according to any one of [1] to [37], wherein the infrared rays from the near-infrared to mid-infrared dryer are irradiated from the side of the protective film to the packaging sheet.

[39] The manufacturing method according to any one of [1] to [38], wherein the distance between the light source of the near-infrared to mid-infrared dryer and the packaging sheet is 5-100 cm.

[40] The manufacturing method of any one of [1] to [38] above, wherein the distance between the light source of the near-infrared to mid-infrared dryer and the packaging sheet is 10 to 50 cm.

[41] The manufacturing method of any one of [1] to [38] above, wherein the distance between the light source of the near-infrared to mid-infrared dryer and the packaging sheet is 10 to 30 cm.

[42] The manufacturing method as described in any one of [1] to [41], wherein the irradiation angle of the infrared rays to the packaging sheet is 0 to 80 degrees.

[43] The manufacturing method according to any one of [1] to [41], wherein the irradiation angle of the infrared rays to the packaging sheet is 0 to 70 degrees.

[44] The manufacturing method according to any one of [1] to [41], wherein the irradiation angle of the infrared rays to the packaging sheet is 0-60 degrees.

[45] The manufacturing method according to any one of the aforementioned [1] to [44], wherein the protective film is a polyethylene terephthalate film, a polyethylene naphthalate film, a polypropylene film or a cyclic olefin polymer物膜。 Material film.

[46] The manufacturing method according to any one of [1] to [44], wherein the protective film is a polyethylene terephthalate film, a polyethylene naphthalate film or a cycloolefin polymer film.

[47] The manufacturing method according to any one of [1] to [44], wherein the protective film is a polyethylene terephthalate film.

[48] The manufacturing method of any one of [1] to [47] above, wherein the thickness of the protective film is 10 to 200 μm.

[49] The manufacturing method of any one of [1] to [47], wherein the thickness of the protective film is 20 to 200 μm.

[50] The manufacturing method as described in any one of [1] to [47], wherein the thickness of the protective film is 10 to 125 μm.

[51] The manufacturing method as described in any one of [1] to [47], wherein the protection The film thickness is 20~125μm.

[52] The manufacturing method of any one of [1] to [51] above, wherein the encapsulation of the organic EL element in step (2) is achieved by contacting the resin composition layer with the organic EL element. Laminated with the substrate.

[53] The manufacturing method of the aforementioned [52], wherein the lamination of step (2) is carried out under an inert gas atmosphere or a vacuum.

According to the method of the present invention, the protective film of the packaging sheet formed by laminating the support, the resin composition layer and the protective film in this order can be effectively dried without peeling off the packaging sheet. In addition, according to the method of the present invention, the packaging sheet can be effectively dried even at a relatively low temperature.

[step 1)]

The method of the present invention includes the step (1) of drying the sealing sheet without peeling off the protective film using a near-infrared to mid-infrared dryer.

(1-1) Near-infrared to mid-infrared dryer

In this specification, the so-called near-infrared to mid-infrared dryer means a dryer that irradiates near-infrared to mid-infrared. Examples of filament (heat source) used in the light source (heater) of the near-infrared to mid-infrared dryer are for example Tungsten, nickel-chromium alloy, carbon, KANTHAL (registered trademark), etc., preferably tungsten, KANTHAL, and particularly preferably tungsten. In order to effectively dry the resin composition layer, it is preferable to use a dryer that can irradiate near-infrared rays to mid-infrared rays with a peak wavelength in the range of 1.0 to 4.0 μm. The peak wavelength is more preferably in the range of 1.0 to 3.5 μm, still more preferably in the range of 1.25 to 3.5 μm, and still more preferably in the range of 1.5 to 3.5 μm. In addition, the near-infrared to mid-infrared region in this specification means the wavelength range of 0.78~4.0μm, the near-infrared region means the range where the wavelength is 0.78μm or more but less than 2.0μm, and the mid-infrared region means the wavelength is 2.0μm or more. The range below 4.0μm. In this specification, near-infrared to mid-infrared rays are sometimes abbreviated as infrared, and near-infrared to mid-infrared dryers are sometimes abbreviated as infrared dryers.

Drying with a near-infrared to mid-infrared dryer is preferably performed under dry air or dry inert gas atmosphere. Examples of the inert gas include nitrogen, argon, helium, and neon. The amount of water vapor contained in the air or inert gas is preferably 0 to 500 ppm (that is, 0 to 500 μmol/mol), more preferably 0 to 250 ppm, still more preferably 0 to 100 ppm, still more preferably 0 to 50 ppm, Especially preferred is 0~30ppm.

In order to avoid adverse effects on the resin composition layer and effectively dry, the drying temperature is preferably 60-160°C, more preferably 60-140°C, still more preferably 60-130°C, and still more preferably 80-130°C , Particularly preferably 90~130°C, and the drying time is preferably 0.5~60 minutes, more preferably 1~30 minutes, still more preferably 5~30 minutes, still more preferably 5~15 minutes. The so-called drying temperature here means the surface temperature of the protective film on the resin composition, which can be measured by installing a surface contact type K thermocouple on the protective film. Also, the so-called drying time It means the time when the surface temperature of the protective film is at a specific drying temperature.

Infrared rays are preferably irradiated to the packaging sheet from the protective film side. In order to effectively dry the packaging sheet, the distance between the light source (heater) of the near-infrared to mid-infrared dryer and the packaging sheet is preferably 5-100 cm, more preferably 10-50 cm, and still more preferably 10-30 cm. The irradiation angle of infrared rays is preferably 0 to 80 degrees, more preferably 0 to 70 degrees, and still more preferably 0 to 60 degrees.

When transporting to an infrared dryer, in order to prevent bending of the packaging sheet, the packaging sheet can be transported to the infrared dryer and dried in a state where the packaging sheet is fixed to a glass substrate, etc.

For drying, a commercially available near-infrared to mid-infrared dryer can be used. Examples of commercially available near-infrared to mid-infrared dryers are, for example, the near-infrared wavelength control system manufactured by NGK INSULATORS, Japan.

(1-2) Packaging sheet

In the step (1), the encapsulation sheet formed by laminating the support, the resin composition layer, and the protective film in this order is dried without peeling the protective film. As the packaging sheet, a conventional packaging sheet can be used.

(1-2-1) Support

Examples of the support for the packaging sheet include polyolefins such as polyethylene and polypropylene (PP), polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), etc. Plastic films of polycarbonate (PC), polyimide (PI), cycloolefin polymer (COP), polyvinyl chloride, etc. Only one type of plastic film may be used, or two or more types may be used in combination. Support body is relatively It is preferably a PET film, a PEN film or a COP film, and more preferably a PET film.

In order to improve the moisture resistance of the packaging sheet, a plastic film with a barrier layer can also be used as a support. In the encapsulation sheet, the barrier layer may be in contact with the resin composition layer, or the barrier layer may not be in contact with the resin composition layer (that is, on the surface of the support body on the opposite side of the support body in contact with the resin composition layer) To form a barrier layer). Examples of the barrier layer include nitrides such as silicon nitride, oxides such as aluminum oxide, and metal foils such as stainless steel foil and aluminum foil. The barrier layer can be a multilayer structure of two or more layers. As for the plastic film with the barrier layer, examples of the plastic film are films such as polyethylene terephthalate, polyethylene naphthalate, polycarbonate, and cycloolefin polymer. The plastic film can also have a multi-layer structure with more than 2 layers. Commercial products can also be used for plastic films with barrier layers. Examples of commercially available products of polyethylene terephthalate film with aluminum foil include "Al (1N30) with PET" manufactured by Tokai Toyo Aluminium Sales Co., Ltd., "AL3025 with PET" manufactured by Fukuda Metal Co., Ltd., and the like.

For example, when the package obtained by the manufacturing method of the present invention is used for display purposes, a polarizing plate can also be used as a support. In addition, the support can also be composed of multiple layers with different functions, such as a plastic film with a barrier layer and a polarizing plate. For example, an adhesive such as an optical adhesive sheet (OCA) can be used to bond a plastic film with a barrier layer and a polarizing plate as a support. In this case, the packaging sheet has a structure in which the plastic film having the barrier layer is in contact with the resin composition layer.

The support can also be subjected to mold release treatment and matting with silicone resin-based mold release agents, alkyd resin-based mold release agents, fluororesin-based mold release agents, etc. Treatment, corona treatment, etc. The thickness of the support is not particularly limited. From the viewpoint of handling properties, the lower limit of the support thickness is preferably 10 μm, more preferably 20 μm, and the upper limit thereof is preferably 200 μm, more preferably 125 μm. The preferred range of the thickness of the support (that is, the preferred combination of upper and lower limits) is (i) 10 to 200 μm, (ii) 20 to 200 μm, (iii) 10 to 125 μm, and (iv) 20 to 125 μm.

(1-2-2)Protective film

Examples of the protective film of the packaging sheet are the same as the plastic film of the support. The protective film is preferably a PET film, a PEN film, a PP film or a COP film, more preferably a PET film, a PEN film or a COP film, and still more preferably a PET film. The protective film may also be subjected to mold release treatment, matting treatment, corona treatment, etc., with silicone resin-based mold release agents, alkyd resin-based mold release agents, fluororesin-based mold release agents, and the like. The protective film may also have a multilayer structure of two or more layers. The thickness of the protective film is not particularly limited. From the viewpoints of handling properties and drying of the packaging sheet, the lower limit of the thickness of the protective film is preferably 10 μm, more preferably 20 μm, and the upper limit thereof is preferably 200 μm, more preferably 125 μm. The preferred range of the thickness of the protective film (that is, the preferred combination of upper and lower limits) is (i) 10~200 μm, (ii) 20~200 μm, (iii) 10~125 μm, and (iv) 20~125 μm.

(1-2-3) Resin composition layer

The packaging sheet used in the present invention may be a thermosetting type packaging sheet or a pressure-sensitive adhesive type packaging sheet. Here, the so-called thermosetting encapsulation sheet means an encapsulation sheet having a layer of thermosetting resin composition, so that After the encapsulation sheet and the substrate are laminated, they are heated to form a hardened resin composition layer (encapsulation layer) sheet. The so-called pressure-sensitive adhesive encapsulation sheet refers to a encapsulation sheet in which an encapsulation layer has been formed, and it is not necessary to heat the encapsulation sheet after the encapsulation sheet and the substrate are laminated. The thermosetting resin composition used to form the resin composition layer of the thermosetting encapsulation sheet is not particularly limited, and conventionally known ones such as those described in WO2010/084938 can be used. The resin composition used to form the resin composition layer of the pressure-sensitive adhesive type encapsulation sheet (hereinafter sometimes referred to as "pressure-sensitive adhesive type composition") is not particularly limited, and WO2013/108731, WO2011/062167 can be used Those who have been acquainted in the past, such as those recorded in the document. The resin composition layer may have a multilayer structure of two or more resin composition layers such as those described in WO2011/016408.

The thermosetting resin composition preferably contains an epoxy resin and a curing agent. The epoxy resin and hardener are not particularly limited, and conventionally known ones can be used. The thermosetting resin composition may contain a thermoplastic resin.

The pressure-sensitive adhesive composition preferably contains an α-olefin resin and an adhesive imparting agent. The α-olefin resin and the adhesion-imparting agent are not particularly limited, and conventionally known ones can be used. Examples of the α-olefin resin include α-olefin polymers such as polyethylene and polyisobutylene. The α-olefin resin may also be a copolymer. Examples of the copolymer include copolymers of different α-olefins, copolymers of α-olefins and monomers other than α-olefins (for example, styrene, non-conjugated diene, etc.).

Both the thermosetting resin composition and the pressure-sensitive adhesive composition may contain additives. Examples of additives are, for example, hygroscopic metal oxidation (E.g. calcium oxide, calcined hydrotalcite, etc.), inorganic fillers other than hygroscopic metal oxides (e.g. silica, mica, talc, etc.).

[Step (2)]

The method of the present invention includes the step (2) of encapsulating the organic EL element with the resin composition layer of the encapsulating sheet after peeling off the protective film from the dried encapsulating sheet. In order to utilize the effect of step (1), step (2) is preferably carried out in the same manufacturing line as step (1). In addition, for the same reason, the period between step (1) and step (2) is preferably within 60 minutes. And for the same reason, it is better to proceed to step (1) and proceed to step (2) (in detail, after step (1), no other steps are performed but step (2)).

(2-1) Substrate

The substrate used in the present invention is not particularly limited, and conventional ones can be used. The substrate is preferably from glass, glass with indium tin oxide (ITO), polyimide (PI), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polycarbonate At least one selected from the group consisting of ester (PC) and cycloolefin polymer (COP). The thickness of the substrate is preferably from 0.1 to 1.0 mm, more preferably from 0.1 to 0.7 mm. The thickness of the organic EL element is preferably from 0.01 to 1 μm, more preferably from 0.05 to 0.5 μm.

The organic EL device may also have other structures for suppressing deterioration due to moisture. For example, a passivation film may be formed on the organic EL element. In this case, the encapsulation sheet starts to be laminated on the passivation film. The passivation film is not particularly limited. For example, _{inorganic films such as SiN, SiON, SiO 2} , Al ₂ O ₃ , and TiO ₂ formed by sputtering, CVD method, etc.; acrylic resin, polyimide-based PARYLENE, etc. can be used. Polymer film, multi-layer structure laminated film with inorganic film; etc. conventional passivation film. The thickness of the passivation film is not particularly limited, but is preferably 1 to 3 μm.

In order to extract light from the organic EL element, any one of the substrate and the support of the packaging sheet must be transparent. For example, when an opaque support (for example, a plastic film with an opaque barrier layer) is used in the packaging sheet, a transparent substrate must be used in order to extract light from the substrate side.

(2-2) Package

The encapsulation is performed by laminating the encapsulation sheet and the substrate so that the resin composition layer and the organic EL element are in contact with each other. In addition, the aforementioned organic EL element also includes organic EL elements having other structures for suppressing deterioration as described above. For example, when the aforementioned organic EL element has a passivation film, "the resin composition layer is in contact with the organic EL element" means "the resin composition layer is in contact with the passivation film of the organic EL element".

In order to prevent the dried encapsulation sheet from re-absorbing moisture, it is preferable to encapsulate the substrate with the organic EL element with the resin composition layer of the encapsulation sheet immediately after drying in step (1). If the time between the drying of step (1) and the beginning of the encapsulation of step (2) is in an atmospheric atmosphere, it is preferably 1 to 60 minutes, more preferably 1 to 30 minutes, and even more preferably 1 to 15 minutes. Preferably, it is 1 to 10 minutes. Here, the "start of encapsulation in step (2)" means the resin composition of the encapsulation sheet after peeling off the protective film from the encapsulation sheet The point when the layer is in contact with the organic EL element.

In order to prevent moisture from being adsorbed on the resin composition layer of the dried packaging sheet, the packaging is preferably performed under an inert gas atmosphere or a vacuum. Examples of the inert gas include nitrogen, argon, helium, and neon. The surrounding pressure (inert gas pressure) during packaging under an inert gas atmosphere is preferably about 1×10 ⁵ Pa. The ambient pressure (degree of decompression) during packaging under vacuum is preferably 1 to 1×10 ³ Pa, more preferably 1 to 1×10 ² Pa.

The device used for lamination is not particularly limited, and conventional ones such as roll laminators, presses, etc. can be used. It is also possible to use a plurality of devices such as a roll laminator and a press in combination.

(2-2-1) Roll Laminator

When using a roll laminator, in order to achieve good adhesion of the resin composition layer to the support, the speed of the roll is preferably 10 to 1500 mm/min, more preferably 100 to 500 mm/min.

In order to avoid damage to the organic EL element, the roll pressure of the roll laminator is preferably 0 to 0.5 MPa, more preferably 0 to 0.3 MPa. The so-called roll pressure here means the pressure applied by the air syringe, which is expressed in gauge pressure (original pressure). The so-called roll pressure of 0 means that the pressing force is 0. When the roll pressure is 0, it is preferable to press the layered product with a press machine described later after layering with a roll laminator.

In order to soften the resin composition layer and improve the followability to the substrate, the roll temperature of the roll laminator is preferably 30 to 120°C, more preferably 40 to 110°C, and even more preferably 50 to 100°C. The roller temperature here means the temperature of the roller surface that is digitally controlled by the built-in heater in the roller, which can be controlled by the surface contact type K thermocouple measurement.

For lamination, a commercially available roll laminator can be used. Examples of commercially available roll laminators are, for example, "LPD2325" manufactured by FUJIPLA, "Roll Laminator VA770H" manufactured by Dasei Laminator, "Roll Laminator VA700", "Roll Laminator VAII-700", and "Roll Laminator VAII-700" manufactured by Hakuto Co., Ltd. Mach630up" and so on. Examples of the material of the roll of the roll laminator are, for example, stainless steel, rubber, etc., preferably silicon rubber.

(2-2-2) Pressing machine

When using a press, in order to prevent the EL element from cracking due to pressure, the pressurization is preferably 0.01 to 0.5 MPa, more preferably 0.01 to 0.3 MPa. The pressurization of the press here refers to the pressure applied to the pressurized body (meaning the pressure applied to the surface of the packaging sheet) controlled by a vacuum hydraulic cylinder or load.

The pressing temperature of the press is preferably 30~120°C, more preferably 40~120°C, still more preferably 50~110°C, still more preferably 60~100°C, and its pressing time is preferably 20~ 450 seconds, more preferably 60~300 seconds. The pressing temperature of the pressing machine here means that a cassette heater is built into the surface of the pressing part of the pressing machine (such as a flat plate such as a metal plate), and the surface temperature of the pressing part is digitally controlled. Even determination.

For stacking, a commercially available press can be used. Examples of commercially available presses include flat presses such as "Batch Vacuum Pressurization Laminator CVP-300" manufactured by MOTON Corporation, and "VHI-2051" vacuum pressurizing presses manufactured by Kitagawa Seiki Co., Ltd. Examples of the material of the pressurized plate are for example Alloys such as stainless steel and iron are preferably stainless steel.

(2-3) Hardening of resin composition layer

When a thermosetting type encapsulation sheet is used, the laminate of the encapsulation sheet and the substrate is heated and cured to form a resin composition layer (that is, an encapsulation layer). Hardening can be performed using, for example, a hot-air circulating oven, an infrared heater, a heat gun, a high-frequency induction heating device, a heating plate, and the like. When using a pressing machine to heat and press for lamination, hardening of the lamination and the resin composition layer may be performed simultaneously. The curing temperature varies with the resin composition layer and support used, but is preferably 80-120°C, more preferably 80-110°C, and curing time is preferably 10 to 120 minutes, more preferably 10 to 60 minutes . The thickness of the formed hardened resin composition layer is preferably 3 to 200 μm, more preferably 5 to 150 μm, and still more preferably 10 to 100 μm.

When a pressure-sensitive adhesive type encapsulation sheet is used, the resin composition layer can be cured by heating the encapsulation sheet before lamination of the encapsulation sheet and the substrate. However, after the packaging sheet and the substrate are laminated, they may be further heated. In order to avoid thermal deterioration of the organic EL element when heating the pressure-sensitive adhesive packaging sheet after lamination, the heating temperature is preferably 50 to 150°C, more preferably 60 to 100°C, and more preferably 60 to 90°C.

The moisture content of the packaging sheet can be measured using the Karl Fischer moisture measuring device under the conditions described in Test Example 1 described later. The moisture content of the sealing sheet can be calculated from the measured moisture (weight) and the weight of the sealing sheet based on the following formula.

Moisture content of the packaging sheet (weight ppm) = (measured moisture) / (weight of the packaging sheet) × 10 ⁶

The moisture content of the packaging sheet after step (1) is preferably 500 wt ppm or less, more preferably 400 wt ppm or less, still more preferably 300 wt ppm or less, particularly preferably 250 wt ppm or less, most preferably 200 wt ppm Below ppm.

In addition, since the moisture contained in the encapsulation sheet is considered to be contained only in the resin composition, the evaluation of the moisture content is preferably based on the assumption that the moisture is contained only in the resin composition layer, based on the conversion into the resin composition layer. The value of the moisture content. The moisture content contained in the resin composition layer can be calculated from the moisture (weight) of the encapsulation sheet measured as described above, the weight of the encapsulation sheet, and the weight ratio of the resin composition layer based on the following formula.

The moisture content of the resin composition layer (weight ppm) = (measured moisture)/(the weight of the packaging sheet × the weight ratio of the resin composition layer) × 10 ⁶

The weight ratio of the resin composition layer used in the above formula can be calculated based on the following formula by measuring the weight of other layers such as the support and the protective film in the encapsulation sheet in advance, for example.

The weight ratio of the resin composition layer = (the weight of the packaging sheet-the weight of the other layers) / the weight of the packaging sheet

The moisture content of the resin composition layer after step (1) is preferably 2000 ppm by weight or less, more preferably 1800 ppm by weight or less, still more preferably 1600 ppm by weight or less, more preferably 1400 ppm by weight or less, and still more preferably It is 1200 ppm by weight or less, particularly preferably 1000 ppm by weight or less, and most preferably 850 ppm by weight or less.

[Example]

The following manufacturing examples, test examples, and examples illustrate the present invention in more detail, but the present invention is not limited to these.

Manufacturing example 1: Manufacturing of thermosetting type packaging sheet 1

Liquid bisphenol A epoxy resin ("jER828EL" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent: about 185g/eq) 56 parts by weight, silane coupling agent ("KBM403" manufactured by Shin-Etsu Chemical Co., Ltd.) 1.2 parts by weight, talc After kneading 2 parts by weight of powder ("FG-15" manufactured by TALC, Japan) and 15 parts by weight of calcined hydrotalcite ("KW2200" manufactured by Kyowa Chemical Company), the mixture was dispersed with a 3-roll mixer to obtain a mixture.

Dissolve 1.5 parts by weight of a hardening accelerator ("U-3512T" manufactured by SUN APRO) in a methyl ethyl ketone (MEK) solution of phenoxy resin ("YL7213B35" manufactured by Mitsubishi Chemical Corporation, concentration: 35% by weight) 81 In a mixture of parts by weight (phenoxy resin: 28.4 parts by weight), the above mixture prepared by dispersing with a 3-roll mixer, solid bisphenol A epoxy resin (manufactured by Mitsubishi Chemical Corporation "jER1001", epoxy equivalent : About 475g/eq) 30 parts by weight of MEK solution (concentration: 80% by weight), organic solvent-dispersed colloidal silica (silica particle size: 10-15nm, solid content: 30% by weight, MEK solvent, Nissan Chemical Industry Co., Ltd. Prepare 20 parts by weight of "MEK-EC-2130Y") and 3 parts by weight of ionic liquid hardener (N-acetylglycine tetrabutylphosphonium salt), and uniformly disperse them with a high-speed rotating mixer to obtain a resin composition paint.

Use plastic film with barrier layer ("Al(1N30) with PET" manufactured by Tokai Toyo Aluminium Sales Co., Ltd.), plastic film: 25μm thick Polyethylene terephthalate (PET) film, barrier layer: 30μm thick aluminum foil) as a support, the resulting resin composition paint is coated with a die mouth so that the thickness of the resin composition after drying becomes 20μm Coat the barrier layer of the support uniformly by the cloth machine, and dry it at 80~100°C (average 90°C) for 5 minutes (residual solvent amount in the resin composition layer: 2% by weight).

A PET film with a thickness of 38 μm treated with an alkyd release agent was used as a protective film, and it was wound into a roll shape while being bonded to the surface of the resin composition layer. The drum-shaped packaging sheet was cut into a width of 507 mm to obtain a packaging sheet 1 (width: 507 mm, length: 336 mm).

Manufacturing example 2: Manufacturing of pressure-sensitive adhesive type packaging sheet 2

In 41 parts by weight of polyisobutylene ("Oppanol B100" manufactured by BASF, 33% by weight IPSOL 150 solution), 20 parts by weight of hydrogenated alicyclic petroleum resin ("Escorez 5340" manufactured by EXXON MOBIL) was mixed with 20 parts by weight of liquid polyisobutylene ( 5 parts by weight of "Tetrax 3T" manufactured by Nippon Oil Corporation and 9 parts by weight of isobutylene modified by maleic anhydride ("HV-300M" manufactured by Nippon Oil Corporation) were uniformly dispersed with a high-speed rotary mixer to obtain a mixed solution. In this mixed solution, 5.3 parts by weight of epoxy resin (“HP7200H” 50% by weight IPSOL 150 solution manufactured by DIC Corporation) and an anionic polymer hardener (2,4,6-ginseng (dicyanomethyl)phenol ) 0.6 parts by weight, uniformly dispersed with a high-speed rotating mixer to obtain the paint.

Use plastic film with barrier layer ("Al with PET (1N30)" made by Tokai Toyo Aluminium Sales Co., Ltd. Plastic film: 25μm thick polyethylene terephthalate (PET) film, barrier layer: 30μm thick aluminum foil ) As a support, the obtained paint is made to the thickness of the resin composition after drying The thickness is 20 μm, uniform coating is performed with a die-nozzle coater, dried at 80°C for 30 minutes, and heated and cured at 130°C for 30 minutes to obtain a resin composition sheet. A 30μm thick PET film treated with a silicone-based release agent is used as a protective film, and it is wound into a roll while being attached to the surface of the resin composition layer. The drum-shaped packaging sheet was cut into a width of 507 mm to obtain packaging sheet 2 (width: 507 mm, length: 336 mm).

Manufacturing example 3: Manufacturing of pressure-sensitive adhesive type packaging sheet 3

Polypropylene/polybutene copolymer modified by maleic anhydride ("T-YP279" manufactured by Starlight PMC Co., Ltd., propylene unit/butene unit=64% by weight/36% by weight, maleic anhydride group concentration 0.464mmol/g , Number average molecular weight 35000, random copolymer, 40% by weight SWASOL solution) 20 parts by weight and 14 parts by weight of calcined hydrotalcite ("DHT-4C" manufactured by Kyowa Chemical Industry Co., Ltd.) are mixed and kneaded with a 3-roll mixer, 50 parts by weight of the purified saturated hydrocarbon resin containing a cyclohexyl ring ("TFS13-030" manufactured by Arakawa Chemical Co., Ltd., 60% by weight toluene solution) was mixed with a high-speed rotary mixer to obtain a homogeneous mixed solution. Propylene/polybutene copolymer modified with glycidyl methacrylate (Xingguang PMC "T-YP276", glycidyl methacrylate modified propylene/polybutene copolymer, propylene Unit/butene unit=64% by weight/36% by weight, glycidyl concentration 0.638mmol/g, number average molecular weight 57,000, inorganic copolymer, 40% by weight SWASOL solution) 14 parts by weight and anionic polymerization hardener (2, 0.5 parts by weight of 4,6-ginseng (dicyanomethyl)phenol) was uniformly dispersed with a high-speed rotating mixer to obtain a paint.

Use plastic film with barrier layer (sold by Tokai Toyo Aluminum The company made "Al with PET (1N30)", plastic film: 25μm thick polyethylene terephthalate (PET) film, barrier layer: 30μm thick aluminum foil) as a support, and the resulting paint is dried The thickness of the resin composition layer was 30 μm, and the coating was uniformly coated with a die-nozzle coater, dried at 80°C for 30 minutes, and heated and cured at 130°C for 60 minutes to obtain a resin composition sheet. A 38μm thick PET film treated with a silicone-based release agent was used as a protective film, and it was wound into a roll while being attached to the surface of the resin composition layer. The drum-shaped packaging sheet was cut into a width of 507 mm to obtain a packaging sheet 3 (width: 507 mm, length: 336 mm).

Test Example 1: Calculation of moisture content of dried packaging sheet and resin composition layer

Use an infrared dryer ("Near Infrared Wavelength Control System" manufactured by NGK INSULATORS, Japan, filament: KANTHAL or tungsten), hot air dryer ("Precision Thermostat" manufactured by YAMATO Scientific Co.), or vacuum dryer ("Precision Thermostat" manufactured by Yamato Scientific Co., Ltd.) "Square vacuum dryer", decompression degree: 100Pa), and the temperature and time shown in Tables 1 to 3 below, to dry the encapsulating sheets 1 to 3 obtained as described above with or without peeling the protective film.

Drying using an infrared dryer is performed by irradiating infrared rays from the protective film side to the sealing sheet in a nitrogen atmosphere (amount of water vapor: 20 ppm or less). The peak wavelength of the infrared rays irradiated from the infrared dryer is around 3μm when the filament is KANTHAL, and around 1.5μm when the filament is tungsten. In addition, infrared rays used for drying of packaging sheets 1 and 3 The filament of the dryer is KANTHAL. The filament of the infrared dryer used for drying the packaging sheet 2 is tungsten. In addition, the distance between the light source (heater) of the infrared dryer and the packaging sheet is adjusted to 15cm, and the infrared radiation angle is adjusted to 0-60 degrees.

Cut out the sample (width: about 100mm, length: about 100mm, weight: 100~300mg) from the dried packaging sheet 1~3, peel off the protective film, and use the Karl Fischer moisture measurement device (Mitsubishi Chemical Analysis) by coulometric titration The company's "Trace Moisture Measuring Apparatus CA-200") measures the moisture of the packaging sheet. The device is composed of a glass container equipped with a heatable sample and a titration device filled with a reaction liquid for titrating the vaporized water when the sample is heated. The vaporized water is moved from the glass container to the reaction liquid side of the titration device by flowing nitrogen gas with a flow rate of 250±25ml/min. The measurement is performed by putting the sample in a glass container replaced with a nitrogen atmosphere (water vapor content <0.1ppm), measuring the moisture vaporized at 130°C, and calculating the moisture content of the packaging sheet and the moisture content of the resin composition layer . The results are shown in Tables 1 to 3 below.

Test Example 2: Evaluation test of the encapsulation property with Ca film of the dried encapsulation sheet

Using a glass substrate on which a Ca film is formed instead of an organic EL element, a simulation test of the encapsulation of an organic EL element is performed, and the encapsulation performance of the dried encapsulation sheet is evaluated.

Specifically, first, Ca is vapor-deposited on a glass substrate (thickness: 700 μm, horizontal: 50 mm, vertical: 50 mm) to form a Ca film (thickness: approximately 300nm, horizontal: 40mm, vertical: 40mm). The resulting glass substrate has a packaging width of 5 mm around the Ca film (that is, the contact width between the glass substrate without the Ca film and the packaging sheet).

Next, the encapsulation sheets 1 to 3 (width: 50 mm, length: 50 mm) described in Test Example 1 were dried at the temperature and time shown in Tables 1 to 3 below, and after drying, the resin composition layer and Ca The method of film contact is to laminate the encapsulation sheet and the glass substrate to encapsulate the Ca film. The lamination was carried out using a roll stacker ("LPD2325" manufactured by FUJIPLA, roll material: rubber) under the conditions of roll temperature: 90°C, roll speed: 360 mm/min, roll pressure: 0.2 MPa, and nitrogen atmosphere. In addition, when using the thermosetting type encapsulation sheet 1, use a hot plate ("HP-2SA" manufactured by AS ONE) to heat the laminate of the encapsulation sheet and the glass substrate at 110°C for 30 minutes in an atmosphere to make the resin composition The layer is thermally hardened.

The laminate of the encapsulation sheet and glass substrate obtained as described above is loaded into an accelerated testing machine ("Small Environmental Tester SH-222" manufactured by ESPEC Corporation, temperature: 60°C, humidity: 90%RH), and Ca (opaque) )+2H ₂ O→Ca(OH) ₂ (transparent), measure the time for the opaque Ca film to shrink by 5mm (start shrinking time) as an index of the encapsulation of the encapsulation sheet, and evaluate it according to the following benchmarks. The longer the initial shrinking time, the better the sealing performance of the packaging sheet. The results are shown in Tables 1 to 3 below.

○: The time to start shrinking is 600 hours or more.

△: The start shrinking time is more than 300 hours and less than 600 hours.

×: The time to start shrinking is less than 300 hours.

Also, when using thermosetting type packaging sheet 1, the resin group The surface of the Ca film was visually observed after the resultant layer was thermally cured, and evaluated based on the following criteria. In addition, the surface of the Ca film when the pressure-sensitive adhesive type sealing sheet 3 was used was visually observed, and evaluated based on the following criteria. The results are shown in Tables 1 and 3 below.

○: The surface of the Ca film remains unchanged before and after packaging, and a mirror-like silver luster is seen.

△: The silver luster on the surface of the Ca film becomes dull and the color becomes gray.

×: The Ca film disappeared, and many irregularities were seen when viewed from the substrate side.

As shown in Table 1, use undried packaging sheet 1 (No.1-5, moisture content of packaging sheet: 1290 wtppm) or use a vacuum dryer without peeling off the protective film and dry packaging sheet 1 (No. .1-4, Moisture content of encapsulation sheet: 768 ppm by weight) In the encapsulation evaluation test, the surface of the Ca film on the glass substrate deteriorated after the resin composition layer was cured. In the encapsulation evaluation test, the encapsulation sheet 1 (No. 1-3, moisture content of the encapsulation sheet: 511 wtppm) dried without peeling the protective film using a hot air dryer (100°C, 5 minutes), the resin After the composition layer is hardened, the surface of the Ca film on the glass substrate is slightly deteriorated. These results teach that encapsulation sheets whose moisture content exceeds 500 ppm by weight are not suitable for encapsulation.

Also, as shown in Table 1, the encapsulation sheet 1 (No.1-2) dried by peeling off the protective film using a hot air dryer (100°C, 5 minutes) has a moisture content of 153 wtppm and a shrinkage time of over 600 When it is small, the moisture content and encapsulation are both good. However, when the protective film is peeled off and dried, the resin composition layer is contaminated during drying, and as a result, there is a risk of adversely affecting the organic EL element.

In addition, as shown in Table 1, by using a near-infrared to mid-infrared dryer (100°C, 5 minutes) without peeling off the protective film, the moisture content of the packaging sheet 1 (No. 1-1) can be reduced to 75 Weight ppm. This presumption is due to the fact that the water in the protective film and the resin composition layer is excited by near-infrared radiation to evaporate through the protective film.

As shown in Table 2, the undried packaging sheet 2 (No. 2-5) has a high moisture content of 2900 ppm by weight, which teaches that it is not suitable for packaging. In addition, the moisture content (No. 2-4) of the packaging sheet 2 dried using a hot air dryer (100°C, 5 minutes) without peeling off the protective film is 1131 ppm by weight, and the shrinking time is relatively short. Less than 300 hours.

Also, as shown in Table 2, by using a hot air dryer to dry at high temperature (No. 2-2, 130°C) or long time (No. 2-3, 840 minutes = 14 hours), even if the protective film is not peeled off, The moisture content of the packaging sheet can also be reduced, and its packaging performance can be improved. However, high-temperature drying may have an adverse effect on the resin composition layer, and the drying efficiency for a long time is poor.

Also, as shown in Table 2, by using a near-infrared to mid-infrared dryer (110°C, 5 minutes), even if the protective film is not peeled off, the seal The moisture content of the mounting sheet 2 (No. 2-1) can also be reduced to 31 wtppm. From this result, it can be seen that drying using a near-infrared to mid-infrared dryer is useful not only for thermosetting encapsulation sheets, but also for pressure-sensitive adhesive encapsulation sheets.

As shown in Table 3, use the undried packaging sheet 3 (No. 3-6, the moisture content of the packaging sheet: 3890 wtppm, the moisture content of the resin composition layer: 18507 wtppm) or use the unpeeled protective film Encapsulation evaluation test of sealing sheet 3 (No.3-3, moisture content of sealing sheet: 1114 wtppm, moisture content of resin composition layer: 5433 wtppm) dried by hot air dryer (130°C, 30 minutes) In this case, the surface of the Ca film on the glass substrate is deteriorated. From these results, it is taught that the encapsulation sheet with the moisture content of the resin composition layer exceeding 2000 ppm by weight is not suitable for encapsulation.

Also, as shown in Table 3, using a hot-air dryer to dry for a long time (No. 3-4, 130°C, 60 minutes), even if the protective film is not peeled off, although the moisture content of the packaging sheet can be reduced to some extent, The drying efficiency deteriorates, and there is a tendency that it is not easy to improve the packaging performance.

Also, as shown in Table 3, by using a near-infrared to mid-infrared dryer, even if the protective film is not peeled off, the packaging sheet 3 (No.3-1 and No.3-2) can be used in a short time (10-30 minutes). The moisture content of) can also be reduced to 57~64wtppm, and the moisture content of the resin composition layer can be reduced to 272~307wtppm, which can improve the encapsulation performance.

Test Example 3: Evaluation of the encapsulation performance of organic EL in a dry encapsulation sheet Price test

Using organic EL elements, evaluate the encapsulation properties of the dried encapsulation sheet.

Specifically, first, an organic EL element (organic film thickness: 110 nm, Al cathode thickness: 100 nm) was formed on a glass substrate with indium tin oxide (ITO) (manufactured by GEOMATEC) so that the light-emitting area became 4 mm ^2.

Next, the encapsulation sheet 1 or 3 (horizontal: 15 mm, vertical: 25 mm) described in Test Example 1 was dried at the temperature and time shown in Tables 4 and 5 below, and after drying, the resin composition was combined with the organic The contact method of the EL element is to laminate the encapsulation sheet and the glass substrate with ITO to encapsulate the organic EL element. The lamination was carried out using a roll stacker ("LPD2325" manufactured by FUJIPLA, roll material: rubber) under the conditions of roll temperature: 90°C, roll speed: 360 mm/min, roll pressure: 0.2 MPa, and nitrogen atmosphere. Also, when using a thermosetting type encapsulation sheet 1, use a hot plate ("HP-2SA" manufactured by AS ONE) to heat the resin sheet and glass substrate at 110°C for 30 minutes in a nitrogen atmosphere to heat the resin composition hardening.

The light-emitting surface of the organic EL element encapsulated by the thus-obtained packaging sheet 1 was observed with a CCD camera (manufactured by KYENCE) at a magnification of 100 times, and the ratio of dark spots in the entire volume of the light-emitting surface immediately after packaging was measured and evaluated. Here, the so-called dark spot refers to the non-luminous part generated when the element is in contact with moisture. The smaller the dark spot ratio, the better the packaging performance of the packaging sheet. The results are shown in Table 4.

○: The proportion of dark spots is less than 1.0%

△: The proportion of dark spots is 1.0% or more and less than 5.0%

×: The ratio of dark spots is 5.0% or more

When using the pressure-sensitive adhesive type encapsulation sheet 3, first, before the acceleration test described later, observe and measure the light-emitting surface of the organic EL element encapsulated with the encapsulation sheet obtained as described above with a CCD camera at a magnification of 100 times Its light-emitting area (initial light-emitting area). Next, the packaging sheet was heated at 85°C for 100 hours in a nitrogen atmosphere, and the deterioration accelerated test was performed. The light-emitting surface of the organic EL device after the acceleration test was observed with a CCD camera at a magnification of 100 times, and the area of the light-emitting surface (remaining light-emitting area) was also measured after the acceleration test. Based on the initial emission area and the remaining emission area measured above, the ratio of the remaining emission area is calculated based on the following formula.

The ratio of luminous residual area (%) = initial luminous area / luminous residual area × 100

The results are shown in Table 5 below.

○: The proportion of luminous residual area is more than 70%

△: The proportion of luminous residual area is more than 50% and less than 70%

×: The proportion of luminous residual area is less than 50%

As shown in Table 4, use undried packaging sheet 1 (No. 1-10, moisture content of packaging sheet: 1290 wtppm) or use a hot air dryer without peeling off the protective film and dry packaging sheet 1 (No. .1-9, Moisture content of encapsulation sheet: 511 wtppm) In the encapsulation evaluation test, there are many dark spots on the light-emitting surface of the organic EL element immediately after encapsulation. The teaching is the same as the result of Test Example 2 using a Ca film. The packaging sheet with a moisture content of more than 500 ppm by weight is not suitable for packaging, but it is also this test example using an organic EL element.

Also, as shown in Table 4, the encapsulation sheet 1 (No. 1-8) dried by peeling off the protective film using a hot air dryer (100°C, 10 minutes), the moisture content of the encapsulation sheet is 107 ppm by weight, and the moisture content is 107 wtppm. After encapsulation, there are fewer dark spots on the light-emitting surface of the organic EL device. However, if the protective film is peeled off and dried, the resin composition is contaminated during drying, and as a result, there is a possibility of adversely affecting the organic EL element.

Also, as shown in Table 4, by using a near-infrared to mid-infrared dryer (90°C, 5 minutes to 10 minutes), even if the protective film is not peeled off, the packaging sheet 1 (No. 1-6 and No. 1- 7) The moisture content can also be reduced to 150 ppm by weight. When using such encapsulated organic EL devices, the proportion of dark spots is small, and they can be well packaged.

As shown in Table 5, use undried packaging sheet 3 (No.3-12, moisture content of packaging sheet: 2900 wtppm) or use a hot air dryer without peeling off the protective film and dry the packaging sheet 3 in a short time (No. 3-10, Moisture content of packaging sheet: 710 wtppm) In the packaging performance evaluation test, the ratio of the residual area of luminescence was greatly reduced. as a result It is considered that due to insufficient drying, moisture remained in the sealing sheet 3, which degraded the organic EL element.

Also, as shown in Table 5, by using a near-infrared to mid-infrared dryer (130°C, 5 minutes to 10 minutes), even if the protective film is not peeled off, the encapsulation sheet 3 (No. 3-7 and No. 3- 8) The moisture content can also be reduced to about 100 ppm by weight. From this result, it can be seen that drying using a near-infrared to mid-infrared dryer is useful not only for thermosetting type packaging sheets, but also for pressure-sensitive adhesive type packaging sheets.

〔Industrial availability〕

According to the method of the present invention, the encapsulation sheet can be effectively dried even without peeling off the protective film of the encapsulation sheet in which the support, the resin composition layer, and the protective film are laminated in this order. Therefore, the method of the present invention can be used to manufacture packages (especially organic EL devices) that encapsulate organic EL devices on a substrate with a resin composition layer.

This application is based on Japanese Patent Application No. 2015-058486 filed in Japan, and the entire content is included in this specification.

Claims (10)

A method for manufacturing a package, which is a method for manufacturing a package for encapsulating an organic EL element on a substrate with a resin composition layer, and includes the following steps: (1) A support, a resin composition layer, and a protective film ( cover film) the packaging sheet laminated in this order, the step of drying with a near-infrared to mid-infrared dryer without peeling off the protective film, and (2) after peeling off the protective film from the dried packaging sheet, use the packaging sheet The resin composition layer encapsulates the organic EL device. Such as the manufacturing method of claim 1, wherein step (2) is performed in the same manufacturing line as step (1). For example, the manufacturing method of claim 1 or 2, wherein step (1) is continued to step (2). Such as the manufacturing method of claim 1 or 2, wherein the time from drying in step (1) to before packaging in step (2) is 1 to 60 minutes. Such as the manufacturing method of claim 1 or 2, wherein the peak wavelength of the near-infrared to the mid-infrared irradiated from the near-infrared to the mid-infrared dryer is within the range of 1.0~3.5μm. Such as the manufacturing method of claim 1 or 2, wherein the drying temperature of the near-infrared to mid-infrared dryer is 60~160℃, and the drying time is 0.5~60 minutes. Such as the manufacturing method of claim 6, wherein the drying temperature of the near-infrared to mid-infrared dryer is 60~130°C. Such as the manufacturing method of claim 1 or 2, wherein after step (1) The moisture content of the sealing sheet is 500 ppm by weight or less. The manufacturing method of claim 1 or 2, wherein the moisture content of the resin composition layer after step (1) is 2000 ppm by weight or less. According to the manufacturing method of claim 1 or 2, wherein the encapsulation of the organic EL device in step (2) is performed by laminating the encapsulation sheet and the substrate so that the resin composition layer and the organic EL device are in contact with each other.