Resin composition and resin sheet

Abstract

To provide a resin composition excellent in sealing performance and a resin sheet using the same.SOLUTION: The resin composition contains a polyolefin-based resin and semi-calcined hydrotalcite. The content of the semi-calcined hydrotalcite is more than 45 mass% based on 100 mass% of a nonvolatile component of the resin composition. The resin composition has a water content of 2,500 ppm or less on a mass basis with respect to the whole resin composition. The resin sheet uses the resin composition.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a resin composition useful for sealing electronic devices and a resin sheet using the same.

Background Art

[0002] In order to protect electronic devices such as organic EL (Electroluminescence) devices and solar cells from moisture, the electronic devices are sealed using a resin composition.

[0003] As a resin composition suitable for sealing electronic devices, those containing a hygroscopic filler in the resin composition are known. For example, Patent Document 1 discloses a sealing sheet composed of a sealing resin composition containing a hygroscopic metal hydroxide and a support and a resin composition layer formed by the sealing resin composition.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the field of electronic devices, there has been an ongoing demand for improving the encapsulation performance of resin compositions used for encapsulating electronic devices (specifically, the performance of suppressing deterioration of the encapsulated site). A resin composition containing a polyolefin-based resin and semi-calcined hydrotalcite is excellent in moisture permeability resistance and transparency and is useful for encapsulating electronic devices. However, when the content of semi-calcined hydrotalcite in the resin composition is increased to improve moisture permeability resistance, despite the increase in the content of semi-calcined hydrotalcite, which is a hygroscopic filler, the deterioration of the encapsulated site over time increases, and it has been found that there is a limit to improving the encapsulation performance. The present invention has been made in view of such circumstances, and an object thereof is to provide a resin composition having excellent encapsulation performance and a resin sheet using the same.

Means for Solving the Problems

[0006] As a result of intensive studies by the present inventors, it has been found that the moisture trapped in the semi-calcined hydrotalcite reaches the encapsulated site over time and causes its deterioration, and when the content of semi-calcined hydrotalcite increases, this deterioration becomes apparent. Also, in order to improve the encapsulation performance, while increasing the content of semi-calcined hydrotalcite to improve moisture permeability resistance, by reducing the internal moisture content in the resin composition brought in by the semi-calcined hydrotalcite, it has been found that improvement in encapsulation performance (moisture permeability resistance and suppression of deterioration of the encapsulated site due to internal moisture) can be achieved.

[0007] The present invention based on the above findings is as follows. [1] A resin composition containing a polyolefin-based resin and semi-calcined hydrotalcite, wherein the content of semi-calcined hydrotalcite is more than 45% by mass based on 100% by mass of the non-volatile content of the resin composition, and the moisture content is 2,500 ppm or less on a mass basis with respect to the entire resin composition. [2] The resin composition according to [1] above, wherein the moisture content is 2,000 ppm or less on a mass basis with respect to the entire resin composition. [3] The resin composition according to [1] or [2], wherein the content of the semi-calcined hydrotalcite is more than 45% by mass and 80% by mass or less based on 100% by mass of the non-volatile content of the resin composition. [4] The resin composition according to any one of [1] to [3] above, which is used for sealing an electronic device. [5] The resin composition according to [4] above, wherein the electronic device is an organic EL device or a solar cell. [6] A resin sheet having a support and a layer of the resin composition according to any one of [1] to [3] provided on the support. [7] The resin sheet according to [6] above, which is used for sealing an electronic device. [8] The resin sheet according to [7] above, wherein the electronic device is an organic EL device or a solar cell.

Advantages of the Invention

[0008] According to the present invention, a resin composition excellent in the sealing performance of an electronic device and a resin sheet using the same can be obtained.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, the present invention will be described in order. The examples, preferred embodiments, etc. described below can be combined with each other as long as they do not contradict each other.

[0010] <Resin Composition> The resin composition of the present invention contains a polyolefin resin and a semi-calcined hydrotalcite. The sealing layer formed from the resin composition containing the semi-calcined hydrotalcite can suppress the deterioration of the electronic device due to moisture entering from the outside air because the semi-calcined hydrotalcite absorbs moisture in the outside air.

[0011] However, in the sealing layer formed from the resin composition containing semi-calcined hydrotalcite, the moisture captured by the semi-calcined hydrotalcite (interlayer water of the semi-calcined hydrotalcite and moisture adhering to the surface of the semi-calcined hydrotalcite are considered) is brought into the sealing layer, and over time, this moisture reaches the electronic device and becomes a factor causing deterioration of the electronic device.

[0012] Therefore, it has been found that it is difficult to improve the sealing performance of the resin composition simply by increasing the amount of semi-calcined hydrotalcite used. Also, as a result of the study by the present inventors, even when the semi-calcined hydrotalcite is dried in advance and blended into the resin composition, the above problem was not solved. This is presumably because even after drying, the semi-calcined hydrotalcite immediately captures moisture in the air and returns to its original state. Therefore, it is necessary to dry the resin composition containing semi-calcined hydrotalcite and reduce the moisture contained in the resin composition to a certain value or less.

[0013] Even when the amount of semi-calcined hydrotalcite used is increased to improve moisture resistance, by sufficiently reducing the water content of the resin composition containing semi-calcined hydrotalcite, the deterioration of the electronic device caused by the moisture in the resin composition brought in from the semi-calcined hydrotalcite can be sufficiently suppressed, and a resin composition with excellent sealing performance can be provided. One of the features of the present invention based on such findings is that the water content of the resin composition is 2,500 ppm or less on a mass basis with respect to the entire resin composition (the entire resin composition including volatile and non-volatile components). This water content is preferably lower (ideally 0 ppm), preferably 2,000 ppm or less, more preferably 1,500 ppm or less, still more preferably 1,000 ppm or less, and particularly preferably 800 ppm or less. This water content can be measured as described in the Examples section below.

[0014] A water content of 2,500 ppm or less can be achieved by methods such as appropriately setting the drying conditions of the resin composition. For example, when the varnish of the resin composition is applied to a support and heated to form a resin composition layer, the heating temperature when forming the resin composition layer (i.e., the heating temperature of the coating film formed by varnish application) is preferably 70 to 150 °C, and the heating time is preferably 10 minutes to 2 hours to form the resin composition layer. Then, further, the drying temperature (heating temperature) is preferably 100 to 180 °C, and the drying time is preferably 10 minutes to 7 weeks. By additionally drying the formed resin composition layer, the water content of the resin composition layer can be made 2,500 ppm or less.

[0015] When the heating temperature for the formation of the resin composition layer and the subsequent additional drying is low, it may take a long time to reduce the water content of the resin composition to 2,500 ppm or less, or it may be difficult to make it 2,500 ppm or less. Therefore, the heating temperature for the formation of the resin composition layer and the subsequent additional drying is preferably somewhat high. However, if the heating temperature is set too high during the formation of the resin composition layer, problems such as air bubbles entering the resin composition layer may occur. Therefore, it is preferable to set the formation temperature of the resin composition layer relatively low and set the temperature of the subsequent additional drying of the resin composition layer higher than the formation temperature of the resin composition layer.

[0016] <Polyolefin resin> The polyolefin resin that can be used in the present invention is not particularly limited as long as it has a skeleton derived from olefin. For example, the polyolefin resin described in Patent Document 1 can be cited as a known one. Olefin is preferably a monoolefin having one olefinic carbon-carbon double bond and / or a diolefin having two olefinic carbon-carbon double bonds. As the monoolefin, preferably, α-olefins such as ethylene, propylene, 1-butene, isobutylene, 1-pentene, 1-hexene, 1-heptene, 1-octene, etc. can be mentioned. As the diolefin, preferably, 1,3-butadiene, isoprene, 1,3-pentadiene, 2,3-dimethylbutadiene, etc. can be mentioned. The olefin-derived skeleton in the polyolefin resin may be one kind or two or more kinds. The polyolefin resin may use only one kind or may use two or more kinds in combination.

[0017] The polyolefin resin may be a homopolymer or a copolymer such as a random copolymer or a block copolymer. Examples of the copolymer include copolymers of two or more olefins and copolymers of olefins and monomers other than olefins such as non-conjugated dienes and styrene. Examples of preferred copolymers include ethylene-non-conjugated diene copolymer, ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene copolymer, ethylene-butene copolymer, propylene-butene copolymer, propylene-butene-non-conjugated diene copolymer, styrene-isobutylene copolymer, styrene-isobutylene-styrene copolymer, etc.

[0018] In addition, examples of the polyolefin resin include the isobutylene-modified resin described in International Publication No. 2011 / 62167, the styrene-isobutylene-modified resin described in International Publication No. 2013 / 108731, etc.

[0019] Polyolefin resins preferably include polybutene resins and polypropylene resins. Here, "polybutene resin" refers to a resin in which the main unit (the unit with the highest content) among all olefin monomer units constituting the polymer is derived from butene, and "polypropylene resin" refers to a resin in which the main unit (the unit with the highest content) among all olefin monomer units constituting the polymer is derived from propylene.

[0020] In the case where the polybutene resin is a copolymer, examples of monomers other than butene include styrene, ethylene, propylene, isoprene, etc. In the case where the polypropylene resin is a copolymer, examples of monomers other than propylene include ethylene, butene, isoprene, etc.

[0021] From the perspective of imparting excellent physical properties such as adhesiveness and adhesion wet heat resistance, it is preferable that the polyolefin resin contains a polyolefin resin having an acid anhydride group (that is, a carbonyloxycarbonyl group (-CO-O-CO-)) and / or a polyolefin resin having an epoxy group. Examples of the acid anhydride group include a group derived from succinic anhydride, a group derived from maleic anhydride, and a group derived from glutaric anhydride. The polyolefin resin can have one or more acid anhydride groups. The polyolefin resin having an acid anhydride group can be obtained, for example, by graft-modifying a polyolefin resin with an unsaturated compound having an acid anhydride group under radical reaction conditions. Alternatively, an unsaturated compound having an acid anhydride group may be subjected to radical copolymerization with an olefin or the like. Similarly, the polyolefin resin having an epoxy group can be obtained, for example, by graft-modifying a polyolefin resin with an unsaturated compound having an epoxy group such as glycidyl (meth)acrylate, 4-hydroxybutyl acrylate glycidyl ether, or allyl glycidyl ether under radical reaction conditions. Alternatively, an unsaturated compound having an epoxy group may be subjected to radical copolymerization with an olefin or the like. One or more polyolefin resins can be used, and a polyolefin resin having an acid anhydride group and a polyolefin resin having an epoxy group may be used in combination.

[0022] As the polyolefin resin having an acid anhydride group, a polybutene resin having an acid anhydride group and a polypropylene resin having an acid anhydride group are preferable. As the polyolefin resin having an epoxy group, a polybutene resin having an epoxy group and a polypropylene resin having an epoxy group are preferable.

[0023] The concentration of acid anhydride groups in the polyolefin resin having acid anhydride groups is preferably 0.05 to 10 mmol / g, more preferably 0.1 to 5 mmol / g. The concentration of acid anhydride groups is obtained from the acid value defined as the number of mg of potassium hydroxide required to neutralize the acid present in 1 g of the resin according to the description of JIS K 2501. Further, the amount of the polyolefin resin having acid anhydride groups in the polyolefin resin is preferably 0 to 70% by mass, more preferably 10 to 50% by mass.

[0024] Also, the concentration of epoxy groups in the polyolefin resin having epoxy groups is preferably 0.05 to 10 mmol / g, more preferably 0.1 to 5 mmol / g. The epoxy group concentration is determined from the epoxy equivalent obtained based on JIS K 7236-1995. Further, the amount of the polyolefin resin having epoxy groups in the polyolefin resin is preferably 0 to 70% by mass, more preferably 10 to 50% by mass.

[0025] From the viewpoint of imparting excellent physical properties such as sealing performance, the polyolefin resin preferably contains both a polyolefin resin having acid anhydride groups and a polyolefin resin having epoxy groups. Such a polyolefin resin can form a crosslinked structure by reacting acid anhydride groups and epoxy groups by heating, and can form a sealing layer excellent in sealing performance and the like. The formation of the crosslinked structure can also be carried out after sealing, but when the object to be sealed, such as an electronic device, is vulnerable to heat, it is desirable to use a sealing film for sealing and form a crosslinked structure when manufacturing the sealing film.

[0026] The ratio of the polyolefin resin having acid anhydride groups to the polyolefin resin having epoxy groups is not particularly limited as long as an appropriate crosslinked structure can be formed, but the molar ratio of epoxy groups to acid anhydride groups (epoxy groups: acid anhydride groups) is preferably 100:10 to 100:400, more preferably 100:25 to 100:350, and particularly preferably 100:40 to 100:300.

[0027] In the resin composition of the present invention, when a polyolefin resin having an epoxy group is used, a polyolefin resin having a functional group (excluding an acid anhydride group) capable of reacting with the epoxy group may be used. Examples of the functional group include a hydroxyl group, a phenolic hydroxyl group, an amino group, a carboxy group, and the like.

[0028] In the resin composition of the present invention, when a polyolefin resin having an acid anhydride group is used, a polyolefin resin having a functional group (excluding an epoxy group) capable of reacting with the acid anhydride group may be used. Examples of the functional group include a hydroxyl group, a primary or secondary amino group, a thiol group, and an oxetane group.

[0029] The number average molecular weight of the polyolefin resin is not particularly limited, but from the viewpoint of providing good coatability of the varnish of the resin composition and good compatibility with other components in the resin composition, it is preferably 1,000,000 or less, more preferably 750,000 or less, still more preferably 500,000 or less, further preferably 400,000 or less, still further preferably 300,000 or less, particularly preferably 200,000 or less, and most preferably 150,000 or less. On the other hand, from the viewpoint of preventing repulsion during coating of the varnish of the resin composition, expressing the sealing performance of the formed resin composition layer, and improving the mechanical strength, this number average molecular weight is preferably 1,000 or more, more preferably 2,000 or more. The number average molecular weight in the present invention is measured by gel permeation chromatography (GPC) method (polystyrene conversion). Specifically, the number average molecular weight by the GPC method can be measured using LC-9A / RID-6A manufactured by Shimadzu Corporation as a measuring device, Shodex K-800P / K-804L / K-804L manufactured by Showa Denko KK as a column, toluene or the like as a mobile phase, at a column temperature of 40 ° C, and calculated using a calibration curve of standard polystyrene.

[0030] The polyolefin resin in the present invention is preferably amorphous from the viewpoint of suppressing the decrease in fluidity due to the thickening of the varnish. Here, amorphous means that the polyolefin resin does not have a distinct melting point. For example, those in which no distinct peak is observed when measuring the melting point by DSC (differential scanning calorimetry) of the polyolefin resin can be used.

[0031] Next, specific examples of the polyolefin resin will be described. Specific examples of the polypropylene resin include "T-YP341" manufactured by Starlight PMC Co., Ltd. (glycidyl methacrylate-modified propylene-butene random copolymer, amount of butene units per 100% by mass of the total of propylene units and butene units: 29% by mass, epoxy group concentration: 0.638 mmol / g, number average molecular weight: 155,000), "T-YP279" manufactured by Starlight PMC Co., Ltd. (maleic anhydride-modified propylene-butene random copolymer, amount of butene units per 100% by mass of the total of propylene units and butene units: 36% by mass, acid anhydride group concentration: 0.464 mmol / g, number average molecular weight: 35,000), "T-YP276" manufactured by Starlight PMC Co., Ltd. (glycidyl methacrylate-modified propylene-butene random copolymer, amount of butene units per 100% by mass of the total of propylene units and butene units: 36% by mass, epoxy group concentration: 0.638 mmol / g, number average molecular weight: 57,000), "T-YP312" manufactured by Starlight PMC Co., Ltd. (maleic anhydride-modified propylene-butene random copolymer, amount of butene units per 100% by mass of the total of propylene units and butene units: 29% by mass, acid anhydride group concentration: 0.464 mmol / g, number average molecular weight: 60,900), "T-YP313" manufactured by Starlight PMC Co., Ltd. (glycidyl methacrylate-modified propylene-butene random copolymer, amount of butene units per 100% by mass of the total of propylene units and butene units: 29% by mass, epoxy group concentration: 0.638 mmol / g, number average molecular weight: 155,000), and the like.

[0032] Specific examples of polybutene-based resins include "HV-1900" (polybutene, number average molecular weight: 2,900) manufactured by ENEOS Corporation (former company name "JXTG Energy"), "HV-300M" (maleic anhydride-modified liquid polybutene (modified product of "HV-300" (number average molecular weight: 1,400)), number average molecular weight: 2,100, number of carboxy groups constituting acid anhydride groups: 3.2 per molecule, acid value: 43.4 mgKOH / g, acid anhydride group concentration: 0.77 mmol / g) manufactured by Toho Chemical Industry Co., Ltd., "Oppanol B100" (polyisobutylene, viscosity average molecular weight: 1,110,000) manufactured by BASF SE, and "N50SF" (polyisobutylene, viscosity average molecular weight: 400,000) manufactured by BASF SE.

[0033] Specific examples of styrene-isobutylene copolymers include "SIBSTAR T102" (styrene-isobutylene-styrene block copolymer, number average molecular weight: 100,000, styrene content: 30 mass%) manufactured by Kaneka Corporation, "T-YP757B" (maleic anhydride-modified styrene-isobutylene-styrene block copolymer, acid anhydride group concentration: 0.464 mmol / g, number average molecular weight: 100,000) manufactured by Starlight PMC Co., Ltd., "T-YP766" (glycidyl methacrylate-modified styrene-isobutylene-styrene block copolymer, epoxy group concentration: 0.638 mmol / g, number average molecular weight: 100,000) manufactured by Starlight PMC Co., Ltd., "T-YP8920" (maleic anhydride-modified styrene-isobutylene-styrene copolymer, acid anhydride group concentration: 0.464 mmol / g, number average molecular weight: 35,800) manufactured by Starlight PMC Co., Ltd., and "T-YP8930" (glycidyl methacrylate-modified styrene-isobutylene-styrene copolymer, epoxy group concentration: 0.638 mmol / g, number average molecular weight: 48,700) manufactured by Starlight PMC Co., Ltd.

[0034] The content of the polyolefin resin in the resin composition of the present invention is not particularly limited. However, from the viewpoints of the sealing performance and handleability of the resin composition, the content is preferably 5% by mass or more, more preferably 10% by mass or more, still more preferably 15% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, still more preferably 35% by mass or less, based on 100% by mass of the non-volatile content of the resin composition.

[0035] <semi-calcined hydrotalcite> Hydrotalcite can be classified into uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite. From the viewpoints of the transparency and moisture permeability resistance of the resin composition, semi-calcined hydrotalcite is used in the present invention.

[0036] Uncalcined hydrotalcite is, for example, a metal hydroxide having a layered crystal structure typified by natural hydrotalcite (Mg 6 Al 2 (OH) 16 CO 3 ·4H 2 O). For example, it consists of a layer [Mg 1-X Al X (OH) 2 X+ as the basic skeleton and an intermediate layer [(CO 3 ) X / 2 ·mH 2 O] X- . The uncalcined hydrotalcite in the present invention is a concept including hydrotalcite-like compounds such as synthetic hydrotalcite. Examples of the hydrotalcite-like compounds include those represented by the following formula (I) and the following formula (II).

[0037] [M 2+ 1-x M 3+ x (OH) 2 x+ ·[(A n- ) x / n ·mH 2 O] x- (I)​​ (In the formula, M 2+ represents divalent metal ions such as Mg 2+ , Zn 2+ , etc., M 3+ represents trivalent metal ions such as Al 3+ , Fe 3+ , etc., A n- represents an n-valent anion such as CO 3 2- , Cl - , NO 3 - , etc., 0 < x < 1, 0 ≤ m < 1, and n is a positive number.) In formula (I), M 2+ is preferably Mg 2+ , M 3+ is preferably Al 3+ , and A n- is preferably CO 3 2- .

[0038] M 2+ x Al 2 (OH) 2x+6-nz (A n- ) z ·mH 2 O (II) (In the formula, M 2+ represents divalent metal ions such as Mg 2+ , Zn 2+ , etc., A n- represents an n-valent anion such as CO 3 2- , Cl - , NO 3 - , etc., x is a positive number of 2 or more, z is a positive number of 2 or less, m is a positive number, and n is a positive number.) In formula (II), M 2+ is preferably Mg 2+ , and A n- is preferably CO 3 2- .

[0039] Semi-calcined hydrotalcite refers to a metal hydroxide having a layered crystal structure obtained by calcining an uncalcined hydrotalcite, in which the amount of interlayer water is reduced or disappeared. "Interlayer water", when explained using the composition formula, refers to "H 2 O" described in the composition formulas of the above-mentioned uncalcined natural hydrotalcite and hydrotalcite-like compounds.

[0040] On the other hand, calcined hydrotalcite is obtained by calcining an uncalcined hydrotalcite or a semi-calcined hydrotalcite, and refers to a metal oxide having an amorphous structure in which not only interlayer water but also hydroxyl groups have disappeared by condensation dehydration.

[0041] Uncalcined hydrotalcite, semi-calcined hydrotalcite and calcined hydrotalcite can be distinguished by their saturated water absorption rates. The saturated water absorption rate of semi-calcined hydrotalcite is 1% by mass or more and less than 20% by mass. On the other hand, the saturated water absorption rate of uncalcined hydrotalcite is less than 1% by mass, and the saturated water absorption rate of calcined hydrotalcite is 20% by mass or more.

[0042] The "saturated water absorption rate" in the present invention means the mass increase rate with respect to the initial mass when a measurement sample (for example, semi-calcined hydrotalcite) is weighed at 1.5 g with a balance, the initial mass is measured, and then left standing in a small environmental test chamber (SH-222 manufactured by Espec Corporation) set at 60 °C and 90% RH (relative humidity) under atmospheric pressure for 200 hours. It is expressed by the following formula (i): Saturated water absorption rate (% by mass) = 100 × (mass after moisture absorption - initial mass) / initial mass (i) and can be determined by this.

[0043] The saturated water absorption rate of semi-calcined hydrotalcite is preferably 3% by mass or more and less than 20% by mass, more preferably 5% by mass or more and less than 20% by mass.

[0044] Furthermore, the uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by the thermogravimetric reduction rate measured by thermogravimetric analysis. The thermogravimetric reduction rate of the semi-calcined hydrotalcite at 280°C is less than 15% by mass, and the thermogravimetric reduction rate at 380°C is 12% by mass or more. On the other hand, the thermogravimetric reduction rate of the uncalcined hydrotalcite at 280°C is 15% by mass or more, and the thermogravimetric reduction rate of the calcined hydrotalcite at 380°C is less than 12% by mass.

[0045] Thermogravimetric analysis can be performed using TG / DTA EXSTAR6300 manufactured by Hitachi High-Tech Sciences Corporation. Weigh 5 mg of hydrotalcite into an aluminum sample pan, and under the atmosphere of a nitrogen flow rate of 200 mL / min, without a lid in an open state, and heat it from 30°C to 550°C at a heating rate of 10°C / min. The thermogravimetric reduction rate can be calculated using the following formula (ii): Thermogravimetric reduction rate (% by mass) = 100 × (mass before heating - mass when reaching a predetermined temperature) / mass before heating (ii) and can be obtained.

[0046] Furthermore, the uncalcined hydrotalcite, semi-calcined hydrotalcite, and calcined hydrotalcite can be distinguished by the peaks and relative intensity ratios measured by powder X-ray diffraction. The semi-calcined hydrotalcite shows peaks that are split into two around 2θ = 8-18° by powder X-ray diffraction, or a peak with a shoulder formed by the combination of two peaks, and the relative intensity ratio of the diffraction intensity of the peak or shoulder that appears on the low-angle side (= low-angle side diffraction intensity) to the diffraction intensity of the peak or shoulder that appears on the high-angle side (= high-angle side diffraction intensity) (low-angle side diffraction intensity / high-angle side diffraction intensity) is 0.001-1,000. On the other hand, the uncalcined hydrotalcite has only one peak around 8-18° or the relative intensity ratio of the diffraction intensities of the peak or shoulder that appears on the low-angle side and the peak or shoulder that appears on the high-angle side is outside the above range. The calcined hydrotalcite does not have characteristic peaks in the region of 8°-18° and has a characteristic peak at 43°. The powder X-ray diffraction measurement was performed using a powder X-ray diffractometer (manufactured by PANalytical, Empyrean) with a counter cathode CuKα (1.5405 Å), voltage: 45 V, current: 40 mA, sampling width: 0.0260°, scanning speed: 0.0657° / s, and measurement diffraction angle range (2θ): 5.0131-79.9711°. The peak search can be performed using the peak search function of the software attached to the diffractometer under the conditions of "minimum significance: 0.50, minimum peak tip: 0.01°, maximum peak tip: 1.00°, peak base width: 2.00°, method: minimum value of second derivative".

[0047] The BET specific surface areas of the semi-calcined hydrotalcite and the calcined hydrotalcite are both preferably 1-250 m 2 / g, more preferably 5-200 m 2 / g. These BET specific surface areas can be calculated using the BET multi-point method by adsorbing nitrogen gas on the sample surface using a specific surface area measuring device (Macsorb HM Model 1210, manufactured by Mountech) according to the BET method.

[0048] The particle size of the semi-calcined hydrotalcite is preferably 1 to 1,000 nm, more preferably 10 to 800 nm in all cases. These particle sizes are the median diameters of the particle size distribution when the particle size distribution is created on a volume basis by laser diffraction scattering particle size distribution measurement (JIS Z 8825).

[0049] As the semi-calcined hydrotalcite, those surface-treated with a surface treatment agent can be used. As the surface treatment agent used for the surface treatment, for example, higher fatty acids, alkylsilanes, silane coupling agents, etc. can be used. Among them, higher fatty acids and alkylsilanes are preferable. One kind or two or more kinds of surface treatment agents can be used.

[0050] Examples of the higher fatty acids include higher fatty acids having 18 or more carbon atoms such as stearic acid, montanic acid, myristic acid, and palmitic acid. Among them, stearic acid is preferable. One kind or two or more kinds of these can be used.

[0051] Examples of the alkylsilanes include methyltrimethoxysilane, ethyltrimethoxysilane, hexyltrimethoxysilane, octyltrimethoxysilane, decyltrimethoxysilane, octadecyltrimethoxysilane, dimethyldimethoxysilane, octyltriethoxysilane, n-octadecyldimethyl(3-(trimethoxysilyl)propyl)ammonium chloride, etc. One kind or two or more kinds of these can be used.

[0052] Examples of silane coupling agents include epoxy-based silane coupling agents such as 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropyl(dimethoxy)methylsilane, and 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane; mercapto-based silane coupling agents such as 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-mercaptopropylmethyldimethoxysilane, and 11-mercaptoundecyltrimethoxysilane; amino-based silane coupling agents such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldimethoxymethylsilane, N-phenyl-3-aminopropyltrimethoxysilane, N-methylaminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyldimethoxymethylsilane; ureido-based silane coupling agents such as 3-ureidopropyltriethoxysilane, vinyl-based silane coupling agents such as vinyltrimethoxysilane, vinyltriethoxysilane, and vinylmethyldiethoxysilane; styryl-based silane coupling agents such as p-styryltrimethoxysilane; acrylate-based silane coupling agents such as 3-acryloxypropyltrimethoxysilane and 3-methacryloxypropyltrimethoxysilane; isocyanate-based silane coupling agents such as 3-isocyanatopropyltrimethoxysilane; sulfide-based silane coupling agents such as bis(triethoxysilylpropyl)disulfide and bis(triethoxysilylpropyl)tetrasulfide; phenyltrimethoxysilane, methacryloxypropyltrimethoxysilane, imidazole silane, triazine silane, etc. These can be used alone or in combination of two or more.

[0053] Surface treatment of semi-calcined hydrotalcite or the like can be carried out, for example, by adding and spraying a surface treatment agent while stirring and dispersing untreated semi-calcined hydrotalcite or the like at room temperature with a mixer and stirring for 5 to 60 minutes. As the mixer, a known mixer can be used. For example, blenders such as V blender, ribbon blender, bubble cone blender, mixers such as Henschel mixer and concrete mixer, ball mill, cutter mill, etc. can be mentioned. Also, when grinding hydrotalcite with a ball mill or the like, the above-mentioned higher fatty acid, alkylsilanes or silane coupling agent can be added for surface treatment. The amount of the surface treatment agent used varies depending on the type of hydrotalcite or the type of the surface treatment agent, etc., but 1 to 10 parts by mass is preferable with respect to 100 parts by mass of the untreated hydrotalcite. In the present invention, the surface-treated semi-calcined hydrotalcite is included in the concept of "semi-calcined hydrotalcite" in the present invention.

[0054] From the viewpoint of exerting the sealing performance of the resin composition in the present invention, the content of the semi-calcined hydrotalcite in the resin composition of the present invention is more than 45% by mass based on 100% by mass of the non-volatile content of the resin composition. This content is preferably 50% by mass or more, more preferably 55% by mass or more, still more preferably 60% by mass or more. Also, the upper limit of this content is not particularly limited as long as the effects of the present invention are exhibited. However, from the viewpoint of the transparency of the resin composition and the like, this content is preferably 80% by mass or less, more preferably 75% by mass or less, still more preferably 70% by mass or less.

[0055] The resin composition of the present invention may contain fillers other than semi-calcined hydrotalcite, as long as the effects of the present invention are not impaired. Examples of fillers other than semi-calcined hydrotalcite include inorganic fillers such as silica, alumina, barium sulfate, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, boron nitride, aluminum borate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium zirconate, calcium zirconate, and silicate, and organic fillers such as rubber particles, silicone powder, nylon powder, and fluororesin powder. The content of the filler other than semi-calcined hydrotalcite is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, still more preferably 20 parts by mass or less, and even more preferably 10 parts by mass or less, based on 100 parts by mass of the content of semi-calcined hydrotalcite.

[0056] <Adhesion promoter> The resin composition of the present invention may further contain an adhesion promoter. The adhesion promoter, also called a tackifier, is a component that imparts adhesiveness to the composition. The adhesion promoter is not particularly limited, and terpene resins, modified terpene resins (hydrogenated terpene resins, terpene phenol copolymer resins, aromatic modified terpene resins, etc.), coumarone resins, indene resins, petroleum resins (aliphatic petroleum resins, hydrogenated alicyclic petroleum resins, aromatic petroleum resins, aliphatic aromatic copolymer petroleum resins, alicyclic petroleum resins, dicyclopentadiene-based petroleum resins and their hydrogenated products, etc.) are preferably used.

[0057] Examples of commercially available products that can be used as an adhesion promoter include the following. Examples of terpene resins include YS Resin PX and YS Resin PXN (both manufactured by Yasuhara Chemical Co., Ltd.). Examples of aromatic-modified terpene resins include YS Resin TO and TR series (both manufactured by Yasuhara Chemical Co., Ltd.). Examples of hydrogenated terpene resins include Clearon P, Clearon M, and Clearon K series (all manufactured by Yasuhara Chemical Co., Ltd.). Examples of terpene-phenol copolymer resins include YS Polyster 2000, Polyster U, Polyster T, Polyster S, and Mighty Ace G (all manufactured by Yasuhara Chemical Co., Ltd.). Examples of hydrogenated alicyclic petroleum resins include Escorez 5300 series and 5600 series (both manufactured by ExxonMobil Corporation). Examples of aromatic petroleum resins include ENDEX 155 (manufactured by Eastman Chemical Company). Examples of aliphatic-aromatic copolymer petroleum resins include Quintone D100 (manufactured by Nippon Zeon Co., Ltd.). Examples of alicyclic petroleum resins include Quintone 1325 and Quintone 1345 (both manufactured by Nippon Zeon Co., Ltd.). Examples of saturated hydrocarbon resins include Alcon P100, Alcon P125, Alcon P140, and TFS13-030 (all manufactured by Arakawa Chemical Industries, Ltd.).

[0058] From the viewpoint that the sheet softens in the lamination process of the resin composition sheet and has a desired heat resistance, the softening point of the adhesion promoter is preferably 50 to 200°C, more preferably 90 to 180°C, and even more preferably 100 to 150°C. The softening point is measured by the ring and ball method in accordance with JIS K2207.

[0059] The tackifier may be used alone or in combination of two or more. The content of the tackifier in the resin composition is not particularly limited. However, from the viewpoint of maintaining good sealing performance of the resin composition, when using a tackifier, its content is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 30% by mass or less with respect to 100% by mass of the non-volatile content of the resin composition. On the other hand, from the viewpoint of having sufficient adhesiveness, when using a tackifier, its content is preferably 5% by mass or more, and more preferably 10% by mass or more with respect to 100% by mass of the non-volatile content of the resin composition.

[0060] From the viewpoints of adhesiveness, sealing performance, transparency, etc. of the resin composition, petroleum resin is preferred. Examples of the petroleum resin include aliphatic petroleum resin, aromatic petroleum resin, aliphatic-aromatic copolymerized petroleum resin, alicyclic petroleum resin, etc. From the viewpoints of adhesiveness, sealing performance, compatibility, etc. of the resin composition, aromatic petroleum resin, aliphatic-aromatic copolymerized petroleum resin, alicyclic petroleum resin are more preferred. Also, from the viewpoint of improving transparency, alicyclic petroleum resin is particularly preferred. As the alicyclic petroleum resin, those obtained by hydrogenating aromatic petroleum resin can also be used. In this case, the hydrogenation rate of the alicyclic petroleum resin is preferably 30 to 99%, more preferably 40 to 97%, and still more preferably 50 to 90%. If the hydrogenation rate is too low, there is a tendency for the transparency to decrease due to coloring, and if the hydrogenation rate is too high, the production cost tends to increase. The hydrogenation rate can be determined from the ratio of the peak intensities of the hydrogen of the aromatic ring before and after hydrogenation by 1 1H-NMR. As the alicyclic petroleum resin, cyclohexane ring-containing hydrogenated petroleum resin and dicyclopentadiene-based hydrogenated petroleum resin are particularly preferred. The petroleum resin may be used alone or in combination of two or more. The number average molecular weight Mn of the petroleum resin is preferably 100 to 2,000, more preferably 700 to 1,500, and still more preferably 500 to 1,000.

[0061] <Curing agent and / or curing accelerator> The resin composition of the present invention may contain a curing agent and / or a curing accelerator (preferably a curing accelerator). As for the curing agent and the curing accelerator, only one kind may be used, or two or more kinds may be used in combination. Examples of the curing agent include imidazole compounds, tertiary / quaternary amine compounds, dimethylurea compounds, organic phosphine compounds, primary / secondary amine compounds, etc. Examples of the curing accelerator include imidazole compounds, tertiary / quaternary amine compounds, dimethylurea compounds, organic phosphine compounds, etc.

[0062] Examples of the imidazole compound which is the curing agent and / or the curing accelerator in the present invention include 1H-imidazole, 2-methylimidazole, 2-phenyl-4-methylimidazole, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2-undecylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, 2,4-diamino-6-(2'-undecylimidazolyl-(1'))-ethyl-s-triazine, 2-phenyl-4,5-bis(hydroxymethyl)imidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 2-phenylimidazole, 2-dodecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,4-diamino-6-(2'-methylimidazolyl-(1')-ethyl-s-triazine, 2,4-diamino-6-(2'-methylimidazolyl-(1'))-ethyl-s-triazine isocyanuric acid adduct, etc. Specific examples of the imidazole compound include Curezol 2MZ, 2P4MZ, 2E4MZ, 2E4MZ-CN, C11Z, C11Z-CN, C11Z-CNS, C11Z-A, 2PHZ, 1B2MZ, 1B2PZ, 2PZ, C17Z, 1.2DMZ, 2P4MHZ-PW, 2MZ-A, 2MA-OK (all manufactured by Shikoku Kasei Kogyo Co., Ltd.), etc.

[0063] As the tertiary or quaternary amine compound as a curing agent and / or a curing accelerator in the present invention, there is no particular limitation, and examples thereof include quaternary ammonium salts such as tetramethylammonium bromide and tetrabutylammonium bromide; diazabicyclo compounds such as DBU (1,8-diazabicyclo[5.4.0]undecene-7), DBN (1,5-diazabicyclo[4.3.0]nonene-5), DBU-phenol salt, DBU-octylate, DBU-p-toluenesulfonate, DBU-formate, and DBU-phenol novolak resin salt; tertiary amines such as benzyldimethylamine, 2-(dimethylaminomethyl)phenol, and 2,4,6-tris(dimethylaminomethyl)phenol (TAP) and their salts; dimethylurea compounds such as aromatic dimethylurea and aliphatic dimethylurea; and the like.

[0064] As the primary or secondary amine compound as a curing agent in the present invention, for example, aliphatic amines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, trimethylhexamethylenediamine, 2-methylpentamethylenediamine, 1,3-bis(aminomethyl)cyclohexane, dipropylenediamine, diethylaminopropylamine, bis(4-aminocyclohexyl)methane, norbornenediamine, 1,2-diaminocyclohexane, etc., alicyclic amines such as N-aminoethylpiperazine, 1,4-bis(3-aminopropyl)piperazine, etc., and aromatic amines such as diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, metaphenylenediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diethyltoluenediamine, etc. Specific examples of the primary or secondary amine compound include Kayahard A-A (manufactured by Nippon Kayaku Co., Ltd.: 4,4'-diamino-3,3'-dimethyldiphenylmethane), etc.

[0065] Specific examples of the dimethylurea compound as a curing agent and / or curing accelerator in the present invention include aromatic dimethylureas such as DCMU (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and U-CAT3512T (manufactured by San-Apro Ltd.), and aliphatic dimethylureas such as U-CAT3503N (manufactured by San-Apro Ltd.). Among them, aromatic dimethylureas are preferably used from the viewpoint of curability.

[0066] Examples of the organic phosphine compound as a curing agent and / or curing accelerator in the present invention include triphenylphosphine, tetraphenylphosphonium tetra-p-tolylborate, tetraphenylphosphonium tetraphenylborate, tri-tert-butylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, triphenylphosphine triphenylborane, etc. Specific examples of the organic phosphine compound include TPP, TPP-MK, TPP-K, TTBuP-K, TPP-SCN, TPP-S (manufactured by Hokko Chemical Industry Co., Ltd.), etc.

[0067] The total content of the curing agent and the curing accelerator in the resin composition is not particularly limited, but from the viewpoint of preventing a decrease in transparency, etc. of the sealing layer (resin composition layer), it is preferably 5% by mass or less, more preferably 1% by mass or less, based on 100% by mass of the non-volatile content of the resin composition. On the other hand, from the viewpoint of suppressing the tack of the sealing layer, the total is preferably 0.0005% by mass or more, more preferably 0.001% by mass or more, based on 100% by mass of the non-volatile content of the resin composition.

[0068] The content of the curing accelerator in the resin composition is not particularly limited, but from the viewpoint of preventing a decrease in transparency or the like of the sealing layer (resin composition layer), it is preferably 5% by mass or less, more preferably 1% by mass or less, based on 100% by mass of the non-volatile content of the resin composition. On the other hand, from the viewpoint of suppressing the tack of the sealing layer, the content is preferably 0.0005% by mass or more, more preferably 0.001% by mass or more, based on 100% by mass of the non-volatile content of the resin composition.

[0069] <Plasticizer> The resin composition of the present invention may further contain a plasticizer. By using a plasticizer, the flexibility and moldability of the resin composition can be improved. The plasticizer is not particularly limited, but a material that is liquid at room temperature is preferably used. Specific examples of the plasticizer include paraffinic process oil, naphthenic process oil, liquid paraffin, polyethylene wax, polypropylene wax, mineral oils such as petrolatum, vegetable oils such as castor oil, cottonseed oil, rapeseed oil, soybean oil, palm oil, coconut oil, olive oil, liquid polybutene, hydrogenated liquid polybutene, liquid polybutadiene, hydrogenated liquid polybutadiene, and other liquid poly-α-olefins. As the plasticizer used in the present invention, liquid poly-α-olefins are preferred, and particularly liquid polybutadiene is preferred. Further, as the liquid poly-α-olefin, those having a low molecular weight are preferred from the viewpoint of adhesiveness, and those having a weight average molecular weight in the range of 500 to 5,000, more preferably 1,000 to 3,000, are preferred. These plasticizers may be used alone or in combination of two or more. Here, "liquid" refers to the state of the plasticizer at room temperature (25°C). When using a plasticizer, from the viewpoint of not adversely affecting the electronic device, the content is preferably 50% by mass or less based on 100% by mass of the non-volatile content of the resin composition.

[0070] <Other components> In the resin composition of the present invention, components other than the above-described components may be optionally contained to the extent that they do not inhibit the effects of the present invention. Examples of such components include resins other than the above-described polyolefin-based resins (for example, epoxy resins, urethane resins, acrylic resins, polyamide resins, etc.); thickeners such as orben and benton; silicone-based, fluorine-based, and polymer-based defoaming agents or leveling agents; adhesion-imparting agents such as triazole compounds, thiazole compounds, triazine compounds, and porphyrin compounds; and the like.

[0071] <Method for producing resin composition> The method for producing the resin composition of the present invention is not particularly limited as long as the water content can be sufficiently reduced. For example, each component and, if necessary, a solvent are mixed, and the resulting mixture is dried to produce a resin composition with a reduced water content.

[0072] It is convenient to dry the mixture by heating. The heating may be performed under normal pressure or under reduced pressure. The heating temperature and heating time may vary depending on the components used. The heating temperature and heating time for sufficiently reducing the water content can be appropriately set by those skilled in the art according to the components used.

[0073] <Resin sheet and method for producing the same> The present invention also provides a resin sheet having a support and a layer of the resin composition of the present invention provided on the support (hereinafter sometimes abbreviated as "resin composition layer").

[0074] The resin composition layer of the resin sheet may be formed by a method known to those skilled in the art. For example, a varnish obtained by dissolving the above-described components in an organic solvent is prepared, and it can be formed by applying and drying the varnish on the support. The non-volatile content of the varnish is preferably 20 to 80% by mass, more preferably 30 to 70% by mass.

[0075] Examples of the organic solvent include ketones such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; acetate esters such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; cellosolves such as cellosolve; carbitols such as butyl carbitol; aromatic hydrocarbons such as toluene and xylene; dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and the like. Only one type of organic solvent may be used, or two or more types may be used in combination.

[0076] It is convenient to dry the varnish by heating. The heating may be performed under normal pressure or under reduced pressure. The heating temperature and heating time may vary depending on the components and the organic solvent used. Those skilled in the art can appropriately set the heating temperature and heating time for sufficiently reducing the water content according to the components and the organic solvent used. Also, the preferable conditions for making the water content of the resin composition layer 2,500 ppm or less are as described above.

[0077] When preparing a resin sheet using a resin composition containing a polyolefin-based resin having an acid anhydride group and a polyolefin-based resin having an epoxy group, by reacting the acid anhydride group and the epoxy group to form a crosslinked structure, the moisture permeability resistance of the layer of the resin composition is enhanced, and a resin sheet with higher sealing performance (such as the performance of blocking moisture and oxygen in the air) can be obtained.

[0078] The thickness of the resin composition layer in the resin sheet is preferably 1 to 1000 μm, more preferably 2 to 800 μm.

[0079] Examples of the support used for the resin sheet include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride; cycloolefin polymers; polyesters such as polyethylene terephthalate (hereinafter sometimes abbreviated as "PET") and polyethylene naphthalate; polycarbonate; plastic films such as polyimide, etc. The surface of the support that is joined to the resin composition layer may be subjected to a release treatment. Examples of the release treatment include release treatment with a release agent such as a silicone resin-based release agent, an alkyd resin-based release agent, or a fluororesin-based release agent.

[0080] The thickness of the support is not particularly limited, but from the viewpoint of the handleability of the resin sheet, etc., 10 to 150 μm is preferable, and 20 to 100 μm is more preferable.

[0081] As the support used for the resin sheet, a support having a barrier layer (for example, a plastic film having a barrier layer) is preferable. Examples of the barrier layer include inorganic films such as a silica vapor deposition film, a silicon nitride film, and a silicon oxide film. The barrier layer may be composed of a plurality of layers of a plurality of inorganic films (for example, a silica vapor deposition film). Further, the barrier layer may be composed of an organic substance and an inorganic substance, or may be a composite multilayer of an organic layer and an inorganic film.

[0082] Examples of the support having a barrier layer include those having a water vapor transmission rate (WVTR) of 0.0005 (g / m 2 / 24hr) or less can be used. Examples of high-barrier plastic films include those manufactured by laminating inorganic films such as silicon oxide (silica), aluminum oxide, magnesium oxide, silicon nitride, silicon nitride oxide, SiCN, and amorphous silicon on the surface of a plastic film in a single layer or multiple layers by chemical vapor deposition (e.g., chemical vapor deposition using heat, plasma, ultraviolet light, vacuum heat, vacuum plasma, or vacuum ultraviolet light) or physical vapor deposition (e.g., vacuum deposition, sputtering, ion plating, laser deposition, and molecular beam epitaxy) (see, for example, JP-A-2016-185705, JP-A-5719106, JP-A-5712509, JP-A-5292358, etc.). In order to prevent cracks in the inorganic film, it is preferable to alternately laminate the inorganic film and a transparent flattening layer (e.g., a transparent plastic layer).

[0083] In addition, the support having a barrier layer may have a WVTR of 0.01 (g / m 2 / 24hr) or more 1(g / m 2 / 24hr) or less can be used. Examples of medium-barrier plastic films include those manufactured by a method of depositing an inorganic film containing an inorganic substance such as silicon oxide (silica), aluminum oxide, magnesium oxide, silicon nitride, silicon nitride oxide, SiCN, or amorphous silicon on the surface of a substrate as a barrier layer, or a method of applying a coating liquid consisting of a metal oxide and an organic resin having barrier properties to the substrate and drying it (see, for example, JP 2013-108103 A and JP 4028353 A).

[0084] The water vapor permeability can be measured as follows. First, a test piece having a diameter of 60 mm is punched out from a plastic film having a barrier layer. -3 m 2Weigh 7.5 g of calcium chloride into a moisture-permeable cup made of aluminum with a diameter of (60 mm φ), and attach the test piece to this moisture-permeable cup. After putting calcium chloride and attaching the test piece, measure the initial mass of the moisture-permeable cup with an analytical balance. Next, place the moisture-permeable cup in a constant temperature test chamber at a temperature of 40 °C and a humidity of 90% RH for 24 hours, and then measure the mass of the moisture-permeable cup with the test piece attached after moisture permeation with an analytical balance. The mass increase (= mass after moisture permeation - initial mass) is taken as the amount of water vapor permeation, and the water vapor permeability (g / m 2 / 24hr) is calculated from the amount of water vapor permeation, the permeation area, and the standing time.

[0085] Commercially available products may be used as the support having a barrier layer. Examples of commercially available medium-barrier plastic films include "Clarista CI" manufactured by Kuraray Co., Ltd., "Tech Barrier HX", "Tech Barrier LX", and "Tech Barrier L" manufactured by Mitsubishi Chemical Corporation, "IB-PET-PXB" manufactured by Dai Nippon Printing Co., Ltd., "GL, GX series" manufactured by Toppan Printing Co., Ltd., etc. Examples of commercially available high-barrier plastic films include "X-BARRIER" manufactured by Mitsubishi Chemical Corporation, etc.

[0086] It is preferable to protect the resin composition layer provided on the support with a protective film. Lamination of the protective film on the resin composition layer can be performed using known equipment. Examples of the equipment used for lamination of the protective film include a roll laminator, a press machine, a vacuum pressure laminator, etc.

[0087] Examples of the protective film include the above-mentioned plastic films, etc. It is preferable that a release treatment is applied to the surface of the protective film that joins the resin composition layer. Examples of the release treatment include release treatment with a release agent such as a silicone resin-based release agent, an alkyd resin-based release agent, a fluororesin-based release agent, etc.

[0088] The thickness of the protective film is not particularly limited, but from the viewpoint of handleability of the resin sheet, etc., 10 to 150 μm is preferable, and 20 to 100 μm is more preferable.

[0089] It is preferable to use a protective film having a barrier layer in order to suppress the resin composition layer from absorbing moisture after drying. Examples of the protective film having a barrier layer include the plastic film having the barrier layer described above. From the viewpoint of cost and the like, it is preferable to use the medium-barrier plastic film described above as the plastic film having a barrier layer to be used for the protective film.

[0090] <Use> The resin composition and resin sheet of the present invention can be used for sealing electronic devices. The electronic device is more preferably an electronic device vulnerable to moisture such as an organic EL device or a solar cell. That is, the resin composition and resin sheet of the present invention can be suitably used particularly for sealing electronic devices vulnerable to moisture such as organic EL devices and solar cells.

Examples

[0091] Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, and it is also possible to appropriately modify and implement within the range that can conform to the above and below gists, and all of them are included in the technical scope of the present invention. In addition, "parts" and "%" in the amount of components and the amount of copolymerized units mean "parts by mass" and "mass%", respectively, unless otherwise specified.

[0092] <Components> The components used in the examples and comparative examples are shown below. (Polyolefin resin) "HV-1900" (manufactured by JXTG Energy Corporation): polybutene, number average molecular weight 2,900 "HV-300M" (manufactured by Toho Chemical Industry Co., Ltd.): maleic anhydride-modified liquid polybutene, acid anhydride group concentration 0.77 mmol / g, number average molecular weight 2,100 「T-YP341」(manufactured by Starlight PMC Co., Ltd.): glycidyl methacrylate-modified propylene-butene random copolymer, propylene unit / butene unit 71% / 29%, epoxy group concentration 0.638 mmol / g, number average molecular weight 155,000 (semi-calcined hydrotalcite) 「DHT-4C」(manufactured by Kyowa Chemical Industry Co., Ltd.): semi-calcined hydrotalcite, average particle diameter 400 nm, BET specific surface area 15 m 2 / g (tackifier) 「Alcon P125」(manufactured by Arakawa Chemical Industries, Ltd.): saturated hydrocarbon resin containing cyclohexane ring, softening point 125 °C (curing accelerator) 2,4,6-tris(dimethylaminomethyl)phenol (hereinafter abbreviated as "TAP"). (manufactured by KAYAKU AKZO Co., Ltd.): curing accelerator

[0093] <Example 1> Varnishes with the formulation ratios shown in the following table were prepared by the following procedure, and resin sheets were prepared using the obtained varnishes. Note that the amounts (parts) of each component described in the following table indicate the amounts of non-volatile components of each component in the varnish. Also, the following table shows the content of the semi-calcined hydrotalcite used as the semi-calcined hydrotalcite relative to 100% by mass of the non-volatile components of the resin composition.

[0094] Specifically, to a solution of cyclohexane ring-containing saturated hydrocarbon resin (tackifier; Alcon P125, manufactured by Arakawa Chemical Industries, Ltd.) in swazol (nonvolatile content: 60%), maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industry Co., Ltd.), polybutene (HV-1900, manufactured by JXTG Energy Corporation), and semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) were dispersed using a three-roll mill to obtain a mixture. To the obtained mixture, a solution of glycidyl methacrylate-modified propylene-butene random copolymer (T-YP341, manufactured by Starlight PMC Co., Ltd.) in swazol (nonvolatile content: 20%), a curing accelerator (TAP, manufactured by KAYAKU Akzo Corporation), and toluene were added, and the resulting mixture was uniformly dispersed using a high-speed rotary mixer to obtain a varnish of the resin composition. The obtained varnish was uniformly applied onto the release-treated surface of a polyethylene terephthalate (PET) film "SP4020" (PET: 50 μm, manufactured by Toyo Boseki Co., Ltd.) treated with a silicone-based release agent using a die coater, heated at 130°C for 30 minutes, and then heated at 160°C for 30 minutes to obtain a resin sheet having a resin composition layer with a thickness of 25 μm.

[0095] <Example 2> A varnish of the resin composition and a resin sheet having a resin composition layer with a thickness of 25 μm were prepared in the same manner as in Example 1, except that the amount of semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) used was changed from 300 parts to 250 parts.

[0096] <Example 3> A varnish of the resin composition and a resin sheet having a resin composition layer with a thickness of 25 μm were prepared in the same manner as in Example 1, except that the amount of semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) used was changed from 300 parts to 200 parts.

[0097] <Example 4> A varnish of the resin composition and a resin sheet having a resin composition layer with a thickness of 25 μm were prepared in the same manner as in Example 1, except that the amount of semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) used was changed from 300 parts to 100 parts.

[0098] <Comparative Example 1> Varnishes having the compounding ratios shown in the following table were prepared by the following procedure, and resin sheets were prepared using the obtained varnishes. In addition, the amount (parts) of each component described in the following table indicates the amount of the non-volatile component of each component in the varnish. Further, the following table shows the content of the semi-calcined hydrotalcite with respect to 100% by mass of the non-volatile component of the resin composition.

[0099] Specifically, a solution of maleic anhydride-modified liquid polybutene (HV-300M, manufactured by Toho Chemical Industry Co., Ltd.), polybutene (HV-1900, manufactured by JXTG Energy Co., Ltd.), and semi-calcined hydrotalcite (DHT-4C, manufactured by Kyowa Chemical Industry Co., Ltd.) was dispersed in a solution of a cyclohexane ring-containing saturated hydrocarbon resin (tackifier; Alcon P125, manufactured by Arakawa Chemical Industries, Ltd.) in Swazol (non-volatile content: 60%) using a three-roll mill to obtain a mixture. To the obtained mixture, a solution of glycidyl methacrylate-modified propylene-butene random copolymer (T-YP341, manufactured by Starlight PMC Co., Ltd.) in Swazol (non-volatile content: 20%), a curing accelerator (TAP, manufactured by Kayaku Akzo Co., Ltd.), and toluene were added, and the obtained mixture was uniformly dispersed using a high-speed rotary mixer to obtain a varnish of the resin composition. The obtained varnish was uniformly applied onto the release-treated surface of a PET film "SP4020" (PET: 50 μm, manufactured by Toyo Boseki Co., Ltd.) treated with a silicone-based release agent using a die coater, heated at 130°C for 30 minutes, and then heated at 160°C for 15 minutes to obtain a resin sheet having a resin composition layer with a thickness of 25 μm.

[0100] <Comparative Example 2> A varnish of the resin composition was prepared in the same manner as in Example 1, and the obtained varnish was uniformly applied onto the release-treated surface of a PET film "SP4020" (PET: 50 μm, manufactured by Toyo Boseki Co., Ltd.) treated with a silicone-based release agent using a die coater, and heated at 130°C for 30 minutes to obtain a resin sheet having a resin composition layer with a thickness of 25 μm.

[0101] <Comparative Example 3> A varnish of the resin composition was prepared in the same manner as in Example 4, and the obtained varnish was uniformly applied onto the release-treated surface of a PET film "SP4020" (PET: 50 μm, manufactured by Toyo Cloth Co., Ltd.) treated with a silicone-based release agent using a die coater, and heated at 130 °C for 60 minutes to obtain a resin sheet having a resin composition layer with a thickness of 25 μm.

[0102] <Comparative Example 4> A resin sheet having a resin composition layer with a thickness of 25 μm was prepared in the same manner as in Comparative Example 3, except that a varnish having the formulation ratio of Comparative Example 4 shown in Table 1 below was prepared.

[0103] Regarding the resin composition layers of the resin sheets obtained in the examples and comparative examples, the transparency was evaluated by the total light transmittance, the moisture resistance (sealing performance) was evaluated by the average moisture intrusion distance, and the suppression of deterioration of the sealed target site due to internal moisture (sealing performance) was evaluated by the reflectance ratio.

[0104] <Water content of the resin composition layer> The resin sheets prepared in the examples and comparative examples were cut into a length of 70 mm and a width of 40 mm, the support (i.e., the PET film "SP4020" treated with a silicone-based release agent) was peeled off, and the resin composition layer was folded and placed into a well-dried screw vial (VABH17, manufactured by Mitsubishi Chemical Analytech Co., Ltd.), and then placed into an electric furnace (VA-236S type, manufactured by Mitsubishi Chemical Analytech Co., Ltd.) directly connected to a Karl Fischer measuring instrument (CA310 type, manufactured by Mitsubishi Chemical Analytech Co., Ltd.). 2 In a nitrogen gas stream, the temperature of the electric furnace was raised to 250 °C, the water desorbed from the measurement sample was collected in the Karl Fischer measurement solution, and the mass of water was measured by a conventional method. From the measured mass of water, the water content (ppm) of the resin composition layer was calculated based on the mass standard with respect to the entire resin composition. The results are shown in the table below.

[0105] <Total light transmittance> The resin sheets prepared in the examples and comparative examples were cut into pieces with a length of 50 mm and a width of 20 mm. The cut resin sheets were laminated onto a glass plate (a microslide glass with a length of 76 mm, a width of 26 mm, and a thickness of 1.2 mm (White Slide Glass S1112 Edge Ground No. 2 manufactured by Matsunami Glass Industries Co., Ltd.)) using a batch vacuum laminator (V-160 manufactured by Nichigo-Morton Co., Ltd.) such that the resin composition layer was in contact with the glass plate. The lamination conditions were as follows: after heating to 80 °C and decompressing for 30 seconds, pressure was applied at 0.3 MPa for 30 seconds. Thereafter, the PET film of the resin sheet was peeled off, and the light transmittance spectrum of the exposed resin composition layer was measured using a fiber spectrophotometer (MCPD-7700, model 311C, manufactured by Otsuka Electronics Co., Ltd., external light source unit: halogen lamp MC-2564 (24 V, 150 W specification)) equipped with a φ60 mm integrating sphere (model name SRS-99-010, reflectance 99%). The total light transmittance (%) at a wavelength of 450 nm was calculated and evaluated according to the following criteria. The results are shown in the table below. The distance between the integrating sphere and the sample (laminate) was set to 0 mm, and glass was used as the reference. Good (○): Total light transmittance is 90% or more Poor (×): Total light transmittance is less than 90%

[0106] <Average moisture intrusion distance> A non-alkali glass square with sides of 50 mm × 50 mm was washed with boiling isopropyl alcohol for 5 minutes and dried at 150 °C for 30 minutes or more. Next, UV ozone cleaning of the non-alkali glass was performed. Using a mask with a distance of 2 mm from the edge, a calcium film (purity 99.8%) was deposited on the cleaned non-alkali glass (thickness 200 nm).

[0107] Except for using an aluminum foil / PET composite film "PET with AL1N30" (aluminum foil: 30 μm, PET: 25 μm, manufactured by Tokai-Toyo Aluminum Sales Co., Ltd.) as the support, in the same manner as in each example and each comparative example, a resin sheet having a laminated structure with a PET / aluminum foil / resin composition layer having the same resin composition layer as in each example and each comparative example was obtained.

[0108] An alkali-free glass and a resin sheet on which a calcium film was deposited using a thermal laminator (Lami Packer DAiSY A4 (LPD2325) manufactured by Fujipla Co., Ltd.) in a glove box were bonded together so that the calcium film and the resin composition layer were in contact with each other to obtain an evaluation sample.

[0109] When calcium comes into contact with water and becomes calcium oxide, it becomes transparent. Therefore, the intrusion of moisture into the evaluation sample can be evaluated by measuring the distance (mm) from the end of the evaluation sample to the calcium film.

[0110] The distance from the end of the evaluation sample obtained as described above to the calcium film was measured at 8 points using a Measuring Microscope MF-U manufactured by Mitutoyo Corporation, and the average value was designated as X2.

[0111] Next, the evaluation sample was placed in a thermo-hygrostat set at a temperature of 85°C and a relative humidity of 85% RH. The distance from the end of the evaluation sample to the calcium film 40 hours after being placed in the thermo-hygrostat was measured at 8 points, and the average value was designated as X1 (mm).

[0112] From the obtained X1 and X2, the average moisture intrusion distance X (= X1 - X2) into the calcium film after being placed in the thermo-hygrostat was calculated, and the moisture permeability resistance of the resin composition layer under high temperature and high humidity was evaluated according to the following criteria. The higher the moisture permeability resistance, the slower the intrusion rate of moisture, and the smaller the value of the average moisture intrusion distance X. The results are shown in the following table. When X is less than 0.1 mm, it is described as "<0.1" in the following table. Also, for Comparative Examples 3 and 4 in which X1 could not be measured due to deterioration of the calcium film by moisture, the results were evaluated as poor (×). Good (○): X is less than 1 mm Poor (×): X is 1 mm or more, or X1 could not be measured due to deterioration of the calcium film by moisture

[0113] <Reflectance ratio> A 50 mm × 50 mm square of alkali-free glass was washed with boiling isopropyl alcohol for 5 minutes and dried at 150 °C for 30 minutes or more. Next, UV ozone cleaning of the alkali-free glass was performed. Using a mask with a distance of 2 mm from the end, a calcium film (purity 99.8%) was deposited on the cleaned alkali-free glass (thickness 200 nm).

[0114] Except for using an aluminum foil / PET composite film "PET with AL1N30" (aluminum foil: 30 μm, PET: 25 μm, manufactured by Tokai-Toyo Aluminum Sales Co., Ltd.) as the support, in the same manner as in each example and each comparative example, a resin sheet having a laminated structure with a PET / aluminum foil / resin composition layer having the same resin composition layer as in each example and each comparative example was obtained.

[0115] In a glove box, using a thermal laminator (manufactured by Fujipla, Lamin Packer DAiSY A4 (LPD2325)), the alkali-free glass on which the calcium film was deposited and the resin sheet were bonded so that the calcium film and the resin composition layer were in contact to obtain an evaluation sample.

[0116] The reflectance spectrum of the evaluation sample obtained as described above was measured using a fiber-type spectrophotometer (MCPD-7700, model 311C, manufactured by Otsuka Electronics Co., Ltd., external light source unit: halogen lamp MC-2564 (24V, 150W specification)) equipped with a φ60 mm integrating sphere (model name SRS-99-010, reflectance 99%), and the reflectance (%) at a wavelength of 850 nm was calculated, and this value was designated as Y2.

[0117] Next, the evaluation sample was heated on a hot plate at 80 °C in a glove box for 39 hours, and then the reflectance spectrum of the heated evaluation sample was measured, and this value was designated as Y1.

[0118] The reflectance ratio Y (= Y1 / Y2) was calculated from the obtained Y1 and Y2, and the suppression of the deterioration of the calcium film due to the moisture contained in the semi-fired hydrotalcite of the resin composition layer was evaluated according to the following criteria. The results are shown in the table below. At this time, for Comparative Examples 1 to 4 in which the reflectance spectrum Y1 could not be measured due to the deterioration of the calcium film by moisture, the results were evaluated as poor (×). Good (○): Reflectance ratio Y is 0.90 or more Fair (△): Reflectance ratio Y is less than 0.90 Poor (×): The reflectance spectrum Y1 cannot be measured due to the deterioration of the calcium film by moisture

[0119]

Table 1

Industrial Applicability

[0120] The resin composition of the present invention and the resin sheet using the same are useful for sealing electronic devices (for example, organic EL devices, sensor devices, solar cells, etc.).

[0121] This application is based on Japanese Patent Application No. 2019-180606 filed in Japan, and the contents thereof are all incorporated herein by reference.

Claims

1. A method for producing a resin sheet having a support and a layer of a resin composition provided on the support, comprising: the resin composition comprises a polyolefin resin and a semi-calcined hydrotalcite, the content of the semi-calcined hydrotalcite being more than 45% by mass relative to 100% by mass of the non-volatile content of the resin composition; The moisture content of the resin composition layer is 2,500 ppm or less based on the mass of the entire resin composition. Manufacturing method.

2. 2. The method according to claim 1, comprising: applying a varnish of the resin composition to a support, heating the varnish to form a layer of the resin composition, and further drying the layer of the resin composition to reduce the water content of the layer of the resin composition to 2,500 ppm or less by mass based on the total resin composition.

3. The method according to claim 2, comprising: applying a varnish of the resin composition to a support, heating at 70 to 150°C for 10 minutes to 2 hours to form a layer of the resin composition, and further drying the formed layer of the resin composition at 100 to 180°C for 10 minutes to 7 weeks to reduce the moisture content of the layer of the resin composition to 2,500 ppm or less by mass based on the total mass of the resin composition.

4. The method according to any one of claims 1 to 3, wherein the content of the semi-calcined hydrotalcite is more than 45% by mass and not more than 80% by mass, based on 100% by mass of the non-volatile content of the resin composition.

5. The method according to any one of claims 1 to 4, wherein the resin sheet is used for sealing an electronic device.

6. The method according to claim 5 , wherein the electronic device is an organic electroluminescence device or a solar cell.

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