Polyurethane resin composition, sealing material, and electrical / electronic parts

Abstract

To provide a resin composition that enables the production of a resin product with high flexibility, high elongation, and superior moisture resistance even when employing biomass-derived raw materials.SOLUTION: A polyurethane resin composition comprises (A) an isocyanate group-containing compound, (B) a polyetherpolyol made from biomass-derived glycol, and (C) an epoxy group-containing compound, where the glycol is 1,3 propanediol and / or 1,4 butanediol.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a polyurethane resin composition, a sealing material, and an electric / electronic part. [Background technology]

[0002] In recent years, the density and integration of electric and electronic components have increased, and there is a demand for improved reliability for each component.

[0003] In order to protect these electric and electronic components, they are sealed with a sealing material, and polyurethane resins are used as such sealing materials (see, for example, Patent Document 1).

[0004] In recent years, various problems have been raised, such as an increase in the amount of waste resin products such as plastic materials, and concerns about global warming due to carbon dioxide generated during the incineration of resin products. For this reason, from the perspective of consideration for the global environment and human health, the production of resin products from resin compositions using raw materials derived from biomass has attracted considerable attention.

[0005] However, resin products produced using resin compositions made from biomass-derived raw materials have the problem of reduced flexibility and therefore low elongation. When such resin products are used in electrical and electronic components, etc., they have the problem of insufficient elongation at break when stress is applied. Polyurethane resins are required to have a moderate elongation. For example, when a polyurethane resin is used to resin-encapsulate the entire printed circuit board of an electrical and electronic component, it is required that the polyurethane resin conform to the deformation of the printed circuit board and maintain high sealing properties. Furthermore, in thermal shock tests and the like, it is required that the polyurethane resin have excellent crack resistance at low temperatures and conform to the molded parts and cases, and furthermore, moisture resistance is also required.

[0006] Therefore, there is a demand for the development of a resin composition that can be used to produce resin products that are highly flexible, have a high elongation rate, and are excellent in moisture resistance, even when using raw materials derived from biomass. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2020-35640 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a resin composition that can be used to produce resin products that have high flexibility, high elongation, and excellent moisture resistance, even when using raw materials derived from biomass. [Means for solving the problem]

[0009] As a result of extensive research, the present inventors have found that the above-mentioned object can be achieved by a polyurethane resin composition containing an isocyanate group-containing compound, a polyether polyol made from a biomass-derived glycol, and an epoxy group-containing compound, in which a specific glycol is used, and have thus completed the present invention.

[0010] That is, the present invention relates to the following polyurethane resin composition, sealing material, and electric / electronic part. 1. A polyurethane resin composition comprising (A) an isocyanate group-containing compound, (B) a polyether polyol made from a biomass-derived glycol, and (C) an epoxy group-containing compound, The glycol is 1,3 propanediol and / or 1,4 butanediol; A polyurethane resin composition characterized by: 2. The polyurethane resin composition according to item 1, wherein the content of the (B) polyether polyol made from a biomass-derived glycol is 25 to 80% by mass, with the polyurethane resin composition being 100% by mass. 3. The polyurethane resin composition according to item 1 or 2, wherein the content of the (C) epoxy group-containing compound is 0.5 to 60 parts by mass per 100 parts by mass of the (B) polyether polyol made from a biomass-derived glycol. 4. The polyurethane resin composition according to item 1 or 2, wherein the content of the (C) epoxy group-containing compound is 0.5 to 35 parts by mass per 100 parts by mass of the (B) polyether polyol made from a biomass-derived glycol. 5. The polyurethane resin composition according to any one of items 1 to 4, wherein the (A) isocyanate group-containing compound is at least one selected from the group consisting of diphenylmethane diisocyanate and modified products thereof, and hexamethylene diisocyanate and modified products thereof. 6. The polyurethane resin composition according to any one of items 1 to 5, wherein the content of the (A) isocyanate group-containing compound is 10 to 40 parts by mass per 100 parts by mass of the (B) polyether polyol made from a biomass-derived glycol. 7. The polyurethane resin composition according to any one of items 1 to 6, further comprising (D) a castor oil-based polyol. 8. The polyurethane resin composition according to Item 7, wherein the content of the (D) castor oil-based polyol is 50 parts by mass or less per 100 parts by mass of the polyurethane resin composition. 9. A sealing material comprising the polyurethane resin composition according to any one of items 1 to 8. 10. An electric / electronic component resin-sealed using the sealing material according to item 9. [Effects of the Invention]

[0011] Even when using a raw material derived from biomass, the polyurethane resin composition of the present invention can be used to produce a resin product that has high flexibility, high elongation, and excellent moisture resistance. DETAILED DESCRIPTION OF THE INVENTION

[0012] The polyurethane resin composition, sealing material, and electric / electronic part of the present invention will be described in detail below.

[0013] 1. Polyurethane resin composition The polyurethane resin composition of the present invention is a polyurethane resin composition containing (A) an isocyanate group-containing compound (hereinafter also referred to as "component (A)"), (B) a polyether polyol (hereinafter also referred to as "component (B)") made from a biomass-derived glycol, and (C) an epoxy group-containing compound (hereinafter also referred to as "component (C)"), wherein the glycol is 1,3-propanediol and / or 1,4-butanediol. In the polyurethane resin composition of the present invention, the component (B) is made from a biomass-derived glycol, and 1,3-propanediol and / or 1,4-butanediol is used as the glycol. Furthermore, the polyurethane resin composition of the present invention contains, in addition to the components (A) and (B), an epoxy group-containing compound as component (C). Because the polyurethane resin composition of the present invention uses a specific glycol as component (B) and an epoxy group-containing compound as component (C), it is possible to produce resin products with high flexibility and high elongation, even when using biomass-derived raw materials.

[0014] The biomass degree of the polyurethane resin composition of the present invention is preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more. The upper limit of the biomass degree of the polyurethane resin composition of the present invention is preferably as high as possible, and may be 100%, 90%, or 80%.

[0015] In this specification, the biomass degree of the polyurethane resin composition and each raw material is measured by the following measurement method.

[0016] How to measure biomass content The biomass degree of each raw material is measured from the C14 content using an accelerator mass spectrometer. The measured biomass degree (%) of each raw material is multiplied by the blending ratio of each raw material and the sum is added up to calculate the biomass degree of the polyurethane resin composition.

[0017] ((A) Isocyanate group-containing compound) The (A) isocyanate group-containing compound used in the polyurethane resin composition of the present invention is not particularly limited, and various compounds conventionally used as isocyanate group-containing compounds in polyurethane resin compositions can be used. Examples of the isocyanate group-containing compound include aliphatic polyisocyanate compounds, alicyclic polyisocyanate compounds, aromatic polyisocyanate compounds, and araliphatic polyisocyanate compounds.

[0018] Examples of the aliphatic polyisocyanate compound include tetramethylene diisocyanate, dodecamethylene diisocyanate, hexamethylene diisocyanate (HDI), 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,5-diisocyanate, and 3-methylpentane-1,5-diisocyanate.

[0019] Examples of the alicyclic polyisocyanate compound include isophorone diisocyanate, hydrogenated xylylene diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, and 1,3-bis(isocyanatemethyl)cyclohexane.

[0020] Examples of aromatic polyisocyanate compounds include tolylene diisocyanate, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-dibenzyl diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, 1,3-phenylene diisocyanate, and 1,4-phenylene diisocyanate.

[0021] Examples of the aromatic aliphatic polyisocyanate compound include dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, and α,α,α,α-tetramethylxylylene diisocyanate.

[0022] The isocyanate group-containing compound may contain an isocyanurate-modified product and / or an allophanate-modified product of the polyisocyanate compound. When the isocyanate group-containing compound contains an isocyanurate-modified product and / or an allophanate-modified product of the polyisocyanate compound, the polyurethane resin composition can exhibit better heat resistance.

[0023] As the component (A), at least one selected from the group consisting of diphenylmethane diisocyanate, modified products of diphenylmethane diisocyanate, hexamethylene diisocyanate, and modified products of hexamethylene diisocyanate can be suitably used.

[0024] The above isocyanate group-containing compounds may be used alone or in combination of two or more.

[0025] The content of the component (A) is preferably 10 to 40 parts by mass, more preferably 15 to 35 parts by mass, based on 100 parts by mass of the polyether polyol (B) made from a biomass-derived glycol. When the upper limit of the content of the component (A) is within the above range, the curability of the polyurethane resin composition is further improved. When the lower limit of the content of the component (A) is within the above range, the hydrolysis resistance and curability of the cured polyurethane resin composition are further improved.

[0026] ((B) Polyether polyols made from biomass-derived glycols) In the polyurethane resin composition of the present invention, component (B) is a polyether polyol made from a biomass-derived glycol, and the biomass-derived glycol is 1,3-propanediol and / or 1,4-butanediol. The glycol is 1,3-propanediol and / or 1,4-butanediol, and any known glycol can be used as long as it is derived from biomass.

[0027] The biomass-derived glycol refers to 1,3 propanediol and / or 1,4 butanediol, which can be synthesized using natural components such as plants as starting materials.

[0028] Component (B) is not particularly limited as long as it is a polyether polyol containing a biomass-derived glycol as a raw material, and may be a copolymer containing a glycol other than the biomass-derived glycol as a raw material, but preferably does not contain any other glycol as a raw material. Such other glycol is not particularly limited, and various glycols conventionally used as polyol components in polyurethane resin compositions can be used.

[0029] Examples of the other glycols include polybutadiene polyol, ethylene glycol, 1,3-propanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,4-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,5-hexanediol, 1,2-hexanediol, 2,5-hexanediol, octanediol, nonanediol, decanediol, diethylene glycol, triethylene glycol, dipropylene glycol, cyclohexanediol, trimethylolpropane, glycerin, and 2-methylpropane. Examples of suitable polyols include 1,2,3-hexanetriol, 1,2,6-hexanetriol, pentaerythritol, polylactone diol, polylactone triol, ester glycol, castor oil-based polyol, polyolefin polyol, polyester polyol, polyether polyol, polycarbonate polyol, acrylic polyol, silicone polyol, fluorine polyol, polytetramethylene glycol, polytetramethylene ether glycol, polypropylene glycol, polyethylene glycol, polycaprolactone polyol, hydrogenated hydroxyl group-containing liquid polyisoprene, and hydrogenated hydroxyl group-containing liquid polybutadiene.

[0030] The content of the (B) component is preferably 25 to 80% by mass, and more preferably 40 to 75% by mass, based on 100% by mass of the polyurethane resin composition of the present invention. When the upper limit of the (B) component content is within the above range, the flexibility and elongation of resin products produced using the polyurethane resin composition are further improved. When the (B) component content is within the above range, the hardness of resin products produced using the polyurethane resin composition is further improved.

[0031] In the polyurethane resin composition of the present invention, the NCO / OH ratio between component (A) and component (B) is preferably 0.6 to 2.0, more preferably 0.7 to 1.5. When the lower limit of the NCO / OH ratio is within the above range, the heat resistance of the polyurethane resin composition is further improved. When the upper limit of the NCO / OH ratio is within the above range, the curability of the polyurethane resin composition is further improved.

[0032] ((C) Epoxy group-containing compound) The epoxy group-containing compound (C) used in the polyurethane resin composition of the present invention is not particularly limited, and various compounds conventionally used in resin compositions can be used.

[0033] The component (C) may be any compound having an epoxy group in the molecule, but is not particularly limited thereto. Preferably, the compound has an average of two or more epoxy groups in one molecule. Examples of the epoxy group-containing compound include glycidyl ether-type epoxy compounds, glycidyl amine-type epoxy compounds, glycidyl ester-type epoxy compounds, and alicyclic (cycloaliphatic) epoxy compounds.

[0034] Examples of glycidyl ether type epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, bisphenol AD ​​type epoxy compounds, cresol novolac type epoxy compounds, phenol novolac type epoxy compounds, α-naphthol novolac type epoxy compounds, bisphenol A type novolac type epoxy compounds, dicyclopentadiene type epoxy compounds, tetrabromobisphenol A type epoxy compounds, brominated phenol novolac type epoxy compounds, tris(glycidyloxyphenyl)methane, and tetrakis(glycidyloxyphenyl)ethane.

[0035] Examples of the glycidylamine type epoxy compound include tetraglycidyldiaminodiphenylmethane, triglycidyl paraaminophenol, triglycidyl meta-aminophenol, and tetraglycidyl meta-xylylenediamine.

[0036] Examples of the glycidyl ester type epoxy compound include diglycidyl phthalate, diglycidyl hexahydrophthalate, and diglycidyl tetrahydrophthalate.

[0037] Examples of cyclic aliphatic (alicyclic) epoxy compounds include epoxycyclohexylmethyl-epoxycyclohexanecarboxylate and bis(epoxycyclohexyl)adipate.

[0038] As the component (C), bisphenol A type epoxy compounds and bisphenol F type epoxy compounds are preferred, and bisphenol A type epoxy compounds are more preferred.

[0039] The component (C) may be used alone or in combination of two or more.

[0040] The content of the (C) component is preferably 0.5 to 35 parts by mass, more preferably 1 to 55 parts by mass, and even more preferably 5 to 40 parts by mass, based on 100 parts by mass of the (B) polyether polyol made from a biomass-derived glycol. When the upper limit of the (C) component content is within the above range, the curability of the polyurethane resin composition is further improved. When the lower limit of the (C) component content is within the above range, the moisture resistance, flexibility, and elongation of a resin product produced by curing the polyurethane resin composition are further improved.

[0041] ((D) Castor oil-based polyol) The polyurethane resin composition of the present invention may contain (D) a castor oil-based polyol (hereinafter also referred to as "component (D)"). When the polyurethane resin composition of the present invention contains component (D), the moisture resistance and insulating properties of a resin product produced using the polyurethane resin composition of the present invention are further improved.

[0042] As component (D), polyols produced using castor oil, castor oil fatty acids, and hydrogenated castor oils or hydrogenated castor oil fatty acids can be used. Examples of such polyols include castor oil, transesterification products of castor oil and other natural fats and oils, reaction products of castor oil and polyhydric alcohols, esterification products of castor oil fatty acids and polyhydric alcohols, and polyols obtained by addition polymerization of these with alkylene oxides.

[0043] The component (D) may be used alone or in combination of two or more.

[0044] The content of the (D) component is preferably 120 parts by mass or less, more preferably 80 parts by mass or less, even more preferably 50 parts by mass or less, and particularly preferably 40 parts by mass or less, based on 100 parts by mass of the (B) polyether polyol derived from biomass-derived glycol. The content of the (D) component is preferably 1 part by mass or more, more preferably 5 parts by mass or more, even more preferably 10 parts by mass or more, and particularly preferably 20 parts by mass or more, based on 100 parts by mass of the (B) polyether polyol derived from biomass-derived glycol. When the upper limit of the (D) component content is within the above range, the moisture resistance of resin products produced using the polyurethane resin composition of the present invention is further improved. When the lower limit of the (D) component content is within the above range, the moisture resistance and insulating properties of resin products produced using the polyurethane resin composition of the present invention are further improved.

[0045] ((E) Plasticizer) The polyurethane resin composition of the present invention may further contain a plasticizer (E) (hereinafter also referred to as "component (E)") in addition to the above components (A) to (D). However, it is preferable that the composition does not contain a plasticizer, as this allows for higher moisture resistance.

[0046] Examples of the plasticizer include phthalates such as dioctyl phthalate, diisononyl phthalate, and diundecyl phthalate; adipic esters such as dioctyl adipate and diisononyl adipate; trimellitic esters such as trioctyl trimellitate and triisononyl trimellitate; and pyromellitic esters such as tetraoctyl pyromellitate and tetraisononyl pyromellitate.

[0047] When the polyurethane resin composition of the present invention contains component (E), the content of component (E) is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, per 100 parts by mass of (B) polyether polyol made from biomass-derived glycol. There is no particular lower limit for the content of component (E), and it may be 1 part by mass or more, or 5 parts by mass or more, per 100 parts by mass of (B) polyether polyol made from biomass-derived glycol.

[0048] (Other additives) The polyurethane resin composition of the present invention may contain other additives in addition to the above components (A) to (E), such as catalysts, antioxidants, moisture absorbents, antifungal agents, silane coupling agents, etc.

[0049] The catalyst is not particularly limited, and conventionally known catalysts used in polyurethane resin compositions can be used. Examples of such catalysts include tin catalysts such as dioctyltin dilaurate, dibutyltin dilaurate, and dioctyltin diacetate; lead catalysts such as lead octoate, lead octenate, and lead naphthenate; bismuth catalysts such as bismuth octoate and bismuth neodecanoate; and amine catalysts such as diethylenetriamine. Furthermore, organometallic compounds, metal complex compounds, and the like can also be used as the catalyst.

[0050] The amounts of the above other additives used may be appropriately determined depending on the intended use, from the ranges specified in the usual amounts added, so as not to impair the desired properties of the polyurethane resin composition.

[0051] (Polyurethane resin composition) The polyurethane resin composition of the present invention may be either a one-component type or a two-component type, but the polyurethane resin composition of the present invention containing components (A), (B), and (C) is usually a two-component type resin composition. In the production method described below, a two-component type resin composition will be described.

[0052] 2. Method for producing polyurethane resin composition The method for producing the polyurethane resin composition of the present invention is not particularly limited, and it can be produced by any conventionally known method used for producing polyurethane resin compositions.

[0053] An example of such a production method is a method for producing the resin composition of the present invention by preparing (B) a component containing a polyether polyol component made from a biomass-derived glycol as a raw material to serve as the first component, preparing (A) a component containing an isocyanate group-containing compound to serve as the second component, and mixing the first and second components to react them to form a polyurethane resin.

[0054] As long as the first component contains the component (B) and the second component contains the component (A), the other component may be contained in either the first component or the second component.

[0055] Specific examples of the first and second components include a first component containing components (B) and (C), and a second component containing component (A). Alternatively, the first component may contain components (B) and (C), and optionally components (D) and (E), and the second component may contain component (A).

[0056] The method for preparing the first component and the second component is not particularly limited, and for example, they can be prepared by a preparation method including step 1 of mixing and stirring the components that respectively constitute the first component and the second component in a kneader.

[0057] In the above step 1, the temperature for mixing and stirring is preferably 60° C. or higher and 120° C. or lower, and the stirring time may be about 30 minutes to 3 hours.

[0058] The first component and the second component are prepared by the above-described step 1.

[0059] The polyurethane resin composition of the present invention is produced in step 2 by mixing the first and second components prepared in step 1. The mixing temperature is not particularly limited and is preferably 23° C. or higher and 60° C. or lower. The mixing time is not particularly limited and may be set appropriately depending on the pot life of the polyurethane resin composition.

[0060] The polyurethane resin composition of the present invention is produced by the step 2 described above.

[0061] 3.Resin cured product The polyurethane resin composition of the present invention can be cured to obtain a cured resin product, which has high flexibility and elongation and is therefore useful as a resin product in the field of electrical and electronic components.

[0062] The cured resin preferably has an initial hardness A of 0 or more, more preferably 5 or more, even more preferably 10 or more, and particularly preferably 15 or more, when the polyurethane resin composition is allowed to stand at 60°C for 16 hours to cure. By setting the lower limit of the initial hardness A within the above range, the cured resin can be more effectively used as a resin product used in the field of electrical and electronic components. Furthermore, the initial hardness A is preferably 70 or less, more preferably 65 or less. By setting the upper limit of the initial hardness A within the above range, the flexibility and elongation of the cured resin can be further improved. In this specification, the initial hardness A of the cured resin is measured according to the method described in the Examples below.

[0063] The hardness of the cured resin after the moisture resistance test is preferably 0 or more, more preferably 5 or more. By setting the lower limit of the hardness after the moisture resistance test within the above range, the cured resin can be more effectively used as a resin product used in the field of electrical and electronic components. Even if the hardness of the cured resin is low, for example, 0, it is preferable that the shape of the cured resin is maintained. Furthermore, the hardness of the cured resin after the moisture resistance test is preferably 70 or less, more preferably 60 or less. By setting the lower limit of the hardness after the moisture resistance test within the above range, the flexibility and elongation of the cured resin are further improved. In this specification, the hardness of the cured resin after the moisture resistance test is measured according to the method described in the Examples below.

[0064] 4. Sealing materials and electrical and electronic parts The present invention also relates to an encapsulant made from the polyurethane resin composition. The encapsulant is required to have a moderate elongation percentage. When the polyurethane resin composition is used to encapsulate the entire printed circuit board of an electrical or electronic component, for example, it is required to conform to the deformation of the printed circuit board and maintain high encapsulation properties. Furthermore, in thermal shock tests and the like, it is required to have excellent crack resistance at low temperatures and conform to the molded components and cases. The encapsulant made from the polyurethane resin composition is suitable for use in electrical or electronic components, including heat-generating electrical or electronic components. Examples of such electrical or electronic components include transformers such as transformer coils, choke coils, and reactor coils, as well as device control boards and various sensors. Such electrical or electronic components encapsulated with the encapsulant of the present invention also constitute the present invention. The electrical or electronic components of the present invention can be used in electric washing machines, toilet seats, water heaters, water purifiers, bathtubs, dishwashers, power tools, automobiles, motorcycles, battery packs, and the like. [Example]

[0065] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples.

[0066] The raw materials used in the examples and comparative examples are shown in Table 1 below.

[0067] [Table 1]

[0068] (Preparation of Polyurethane Resin Composition) The raw materials for the first component shown in Table 2 were charged into a reaction vessel and stirred at room temperature and atmospheric pressure for 1 hour to prepare the first component.

[0069] The raw materials for the second component shown in Table 2 were placed in a reactor equipped with heating, cooling, and pressure reduction devices, and dehydration and reaction were carried out at 60°C and a pressure of 10 mmHg or less for 1 hour to prepare the second component.

[0070] A polyurethane resin composition was obtained by adding the second component to the first component, stirring, degassing, and mixing according to the formulation shown in Table 2. The first and second components were mixed by adjusting the first component to 23°C, then adding the second component, which had also been adjusted to 23°C, and mixing at 2000 rpm for 1 minute using a planetary centrifugal mixer (Thinky Corporation, Awatori Rentaro).

[0071] Preparation of test specimens The polyurethane resin composition was poured into a molding die (test piece 1) of 130 × 130 × 3 mm and a molding die (test piece 2) of 30 mm inner diameter and 10 mm height. The polyurethane resin composition was then heated at 60°C for 16 hours and then left to harden at room temperature for one day to prepare a test piece.

[0072] The following tests were carried out using test pieces prepared using the polyurethane resin compositions of the Examples and Comparative Examples as described above.

[0073] Hardness A (initial hardness A) Using test piece 2 (inner diameter 30 mm, height 10 mm), the hardness (Type A) was measured at a temperature of 23°C using a hardness meter (Asker Rubber Hardness Meter Type A, manufactured by Kobunshi Keiki Co., Ltd.) according to the measurement method in accordance with JIS K6253.

[0074] volume resistivity The volume resistivity of the test piece 1 (130×130×3 mm) was measured using a resistance measuring device (manufactured by HIOKI, DSM-8104).

[0075] Elongation (flexibility) Using test piece 1 (130 × 130 × 3 mm), the gauge length at break was measured according to a measurement method in accordance with JIS K6251, and the elongation (flexibility) was calculated according to the following formula. The elongation was also defined as the initial elongation. Elongation (%) = [(gauge length at break - gauge length) / gauge length] x 100

[0076] Hardness after humidity resistance test Using test piece 2 (inner diameter 30 mm, height 10 mm), a pressure cooker test (PCT test) was carried out under conditions of 121°C, 100% RH, 2 atmospheres, and 140 hours. After the test, the hardness of test piece 2 was measured using the above-mentioned hardness A measurement method.

[0077] Change in elongation (flexibility) after humidity resistance test Using test piece 1 (130 × 130 × 3 mm), a moisture resistance test (pressure cooker test (PCT test)) was conducted under conditions of 121°C, 100% RH, 2 atmospheres, and 140 hours. Using test piece 1 after the moisture resistance test, the elongation after the moisture resistance test was measured using the above-mentioned method for measuring elongation (flexibility), and the rate of change in elongation after the moisture resistance test was calculated according to the following formula. Change in elongation (%) = [(elongation after humidity resistance test - initial elongation) / initial elongation)] x 100

[0078] The results are shown in Tables 2 and 3.

[0079] [Table 2]

[0080] [Table 3]

Claims

1. A polyurethane resin composition comprising (A) an isocyanate group-containing compound, (B) a polyether polyol made from a biomass-derived glycol, and (C) an epoxy group-containing compound, the glycol is 1,3 propanediol and / or 1,4 butanediol; 1. A polyurethane resin composition, wherein the (A) isocyanate group-containing compound is at least one selected from the group consisting of diphenylmethane diisocyanate and modified products thereof, and hexamethylene diisocyanate and modified products thereof.

2. 2. The polyurethane resin composition according to claim 1, wherein the content of the (B) polyether polyol made from a biomass-derived glycol is 25 to 80% by mass, with the polyurethane resin composition being 100% by mass.

3. 2. The polyurethane resin composition according to claim 1, wherein the content of the epoxy group-containing compound (C) is 0.5 to 60 parts by mass relative to 100 parts by mass of the polyether polyol (B) derived from a biomass-derived glycol.

4. 2. The polyurethane resin composition according to claim 1, wherein the content of the (C) epoxy group-containing compound is 0.5 to 35 parts by mass per 100 parts by mass of the (B) polyether polyol derived from a biomass-derived glycol.

5. 2. The polyurethane resin composition according to claim 1, wherein the content of the (A) isocyanate group-containing compound is 10 to 40 parts by mass per 100 parts by mass of the (B) polyether polyol made from a biomass-derived glycol.

6. The polyurethane resin composition according to claim 1, further comprising (D) a castor oil-based polyol.

7. 7. The polyurethane resin composition according to claim 6, wherein the content of the castor oil-based polyol (D) is 50 parts by mass or less, based on 100 parts by mass of the polyurethane resin composition.

8. A sealing material comprising the polyurethane resin composition according to any one of claims 1 to 7.

9. An electric / electronic component resin-sealed with the sealing material according to claim 8.

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