Easily detachable resin composition, structure comprising cured product of easily detachable resin composition, method for disassembling structure, and method for recovering material constituting structure

Abstract

The easily detachable resin composition according to the present invention contains a thermosetting resin, and has an adhesion strength ratio (S2 / S1) of 0.30 or less as measured by the following steps. And a step for molding the easily detachable resin composition on a copper substrate under the conditions of 175 DEG C, 6.9 MPa and 120 seconds, and then post-curing at 175 DEG C for 4 hours to obtain a test piece. S1 [N / mm2] is the adhesion strength [N / mm2] when shear adhesion to the copper substrate is measured at a speed of 300 [mu] m / sec at room temperature using the test piece. Furthermore, after the test piece is heated at 300 DEG C for 30 minutes, the adhesion strength [N / mm2] when shear adhesion with the copper substrate is measured at a speed of 300 [mu] m / sec at room temperature is set to be S2 [N / mm2].

Description

Technical Field

[0001] This invention relates to a disintegrating resin composition, a structure comprising a cured product of the disintegrating resin composition, a method for disintegrating the structure, and a method for recycling the materials constituting the structure. Background Technology

[0002] In recent years, the automotive industry has actively promoted vehicle electrification in order to address global climate change and achieve a carbon-neutral society. The neodymium magnets used in most of the motors of these electric vehicles utilize rare elements such as neodymium and dysprosium, which are considered rare earth elements.

[0003] On the other hand, there are concerns about the uneven distribution of rare earth resources and price fluctuations caused by supply and demand imbalances. Moreover, mining and smelting rare earths can also burden the ecosystem. Therefore, reducing their use has become a technical problem.

[0004] Therefore, in the automotive industry, technologies related to the efficient use of rare earth elements and their reuse have attracted attention as a means of resource utilization.

[0005] For example, it is known that magnets can be removed from motors that do not meet shipping standards and cannot be mounted on automobiles, and then disassembled and reused. Additionally, for example, Patent Document 1 discloses a method in which, after heating the rotor to a high temperature, either the Curie temperature or the ashing temperature of the adhesive, vibrations are applied to the metal plate at the end face of the rotor to cause the metal plate to resonate, thereby causing the adhesive and the magnet to detach from the hole.

[0006] Prior art literature Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2015-216777 Summary of the Invention

[0007] The technical problem that the invention aims to solve However, in the prior art disclosed in Patent Document 1, the process of removing rare earth elements from the magnet of the motor involves manual operation to decompose and remove the magnet. Therefore, there is room for improvement in terms of simplifying the process and reducing recycling costs. In addition, when it is desired to remove the magnet by heating at high temperature (approximately 600–700°C) to ashing the adhesive, carbon dioxide will be generated unless the heat energy is clean.

[0008] The inventors of this invention conducted in-depth research to solve this problem and discovered that it is effective for cured resin compositions used in applications such as rotor fixing to have a defined structure and defined physical properties. Specifically, they obtained insights into how controlling the adhesion to copper in the cured product obtained by curing the resin composition can lead to differences in disintegration properties, and proposed new indicators.

[0009] Means for solving technical problems The present invention provides the following easily disintegrating resin composition, a structure comprising a cured product of the easily disintegrating resin composition, a method for disintegrating the structure, and a method for recycling the materials constituting the structure.

[0010] [1] A disintegrating resin composition comprising a thermosetting resin, wherein the disintegrating resin composition is characterized in that: The following steps were used to determine the seal strength ratio (S2 / S1) to be below 0.30.

[0011] [step] The easily disintegrating resin composition was molded onto a copper substrate at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours to obtain a test piece.

[0012] The test piece will be used to determine the shear strength [N / mm] of the copper substrate at room temperature and a speed of 300 μm / s. 2 Set as S1[N / mm] 2 ].

[0013] Furthermore, after heating the test piece at 300°C for 30 minutes, the adhesion strength [N / mm] with the copper substrate was measured at room temperature at a speed of 300 μm / s. 2 Set as S2[N / mm] 2 ].

[0014] [2] The easily disintegrating resin composition according to [1] is characterized in that: The adhesion strength (S2) measured by the above steps is 3.0 N / mm. 2 the following.

[0015] [3] The easily disintegrating resin composition according to [1] or [2] is characterized in that: The easily disintegrating resin composition was molded at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours. The resulting cured product had a linear expansion coefficient α2 of 46 ppm / °C or higher in the temperature range of 190°C to 230°C.

[0016] [4] The easily disintegrating resin composition according to any one of [1] to [3], characterized in that: The easily disintegrating resin composition was molded at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours. The resulting cured product had a linear expansion coefficient α3 of 60 ppm / °C or higher in the temperature range of 250–260°C.

[0017] [5] The easily disintegrating resin composition according to any one of [1] to [4], characterized in that: The thermosetting resin includes one or more selected from epoxy resin, phenoxy resin, polyimide resin, benzoxazine resin, unsaturated polyester resin, phenolic resin, melamine resin, silicone resin, cyanate ester resin, bismaleimide resin and acrylic resin.

[0018] [6] The easily disintegrating resin composition according to any one of [1] to [5] is characterized in that: It also contains a curing agent.

[0019] [7] The easily disintegrating resin composition according to [6] is characterized in that: The curing agent includes a phenolic curing agent.

[0020] [8] The easily disintegrating resin composition according to any one of [1] to [7], characterized in that: It also contains a thermally expandable inorganic material, the content of which is 5 to 98% by mass relative to the total amount of the easily disintegrating resin composition.

[0021] [9] The easily disintegrating resin composition according to [8] is characterized in that: The thermally expandable inorganic material includes one or more selected from crystalline silicon dioxide, crystalline aluminum phosphate, and their derivatives.

[0022]

[10] The easily disintegrating resin composition according to [8] or [9] is characterized in that: The thermally expandable inorganic material includes one or more of the following: quartz-type silica, cristobalite-type silica, tridymite-type silica, berlinite-type aluminum phosphate, tridalphite-type aluminum phosphate, crystalphite-type aluminum phosphate, and carnegieite.

[0023]

[11] The easily disintegrating resin composition according to any one of [1] to

[10] , characterized in that: It also contains aluminum hydroxide.

[0024]

[12] The easily disintegrating resin composition according to

[11] is characterized in that: The content of aluminum hydroxide is 1% by mass or more relative to the total amount of the easily disintegrating resin composition.

[0025]

[13] The easily disintegrating resin composition according to any one of [1] to

[12] , characterized in that: It contains one or more selected from thermally expandable inorganic materials, inorganic fillers, and aluminum hydroxide. The total content of the thermally expandable inorganic material, the inorganic filler material, and the aluminum hydroxide is 60% or more by mass relative to the total amount of the easily disintegrating resin composition.

[0026]

[14] The easily disintegrating resin composition according to any one of [1] to

[13] , characterized in that: The easily disintegrating resin composition is in powder, granule, or ingot form.

[0027]

[15] A structure characterized in that: a cured product comprising any one of the easily disintegrating resin compositions described in [1] to

[14] .

[0028]

[16] A method for dismantling a structure, which is the method for dismantling the structure described in

[15] , characterized in that it includes: The process of heating the structure to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

[0029]

[17] A recycling method, which is a method for recycling materials constituting the structure described in

[15] , characterized in that it includes: The process of heating the structure to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the structure.

[0030]

[18] The easily disintegrating resin composition according to any one of [1] to

[14] is characterized in that: The easily disintegrating resin composition is used to form the stationary components in the rotor. The rotor includes: The rotor core is fixedly mounted on a rotating shaft and has a plurality of holes arranged along the periphery of the rotating shaft; A magnet, which is inserted into the hole; and The fixing component is disposed in the space between the hole and the magnet.

[0031]

[19] A rotor, characterized in that: a cured product of the easily disintegrating resin composition described in

[18] is used as the fixing component.

[0032]

[20] A method for dismantling a rotor, which is the method for dismantling a rotor as described in

[19] , characterized in that it includes: The process of heating the rotor to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

[0033]

[21] A recycling method for recycling materials constituting the rotor described in

[19] , characterized in that it comprises: The process of heating the rotor to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the rotor.

[0034]

[22] The recycling method according to

[21] is characterized in that: The material is selected from one or more of the magnet inserted into the hole and the electromagnet plate.

[0035]

[23] The easily disintegrating resin composition according to any one of [1] to

[14] is characterized in that: The easily disintegrating resin composition is used to form a sealing component in the stator. The stator has: a stator core having a plurality of teeth and a plurality of slots alternately formed in the circumferential direction; a coil wound in and housed in the slots, and having a pair of coil ends protruding from the stator core to both sides in the axial direction; and the sealing member provided in such a way as to cover the coil in the slots.

[0036]

[24] A stator, characterized in that: a cured product of the easily disintegrating resin composition described in

[23] is used as the sealing component.

[0037]

[25] A method for dismantling a stator, which is the method for dismantling a stator described in

[24] , characterized in that it includes: The process of heating the stator to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

[0038]

[26] A recycling method for recycling materials constituting the stator described in

[24] , characterized in that it includes: The step of heating the stator to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the stator.

[0039]

[27] The recycling method according to

[26] is characterized in that: The material is selected from one or more of coils and electromagnet steel plates.

[0040]

[28] The easily disintegrating resin composition according to any one of [1] to

[14] is characterized in that: The easily disintegrating resin composition is used to form sealing components in the power module. The power module includes: a wiring board; a plurality of electronic components mounted on the wiring board; and a sealing component that seals the electronic components.

[0041]

[29] A power module, characterized in that: a cured product of the easily disintegrating resin composition described in

[28] is used as the sealing component.

[0042]

[30] A method for dismantling a power module, which is the method for dismantling a power module as described in

[29] , characterized in that it includes: The process of heating the power module to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

[0043]

[31] A recycling method for recycling materials constituting the power module described in

[29] , characterized in that it includes: The process of heating the power module to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the power module.

[0044]

[32] The recycling method according to

[31] is characterized in that: The material is a metal lead frame.

[0045] Effects of the Invention Using this invention, cured products of easily disintegrating resin compositions containing thermosetting resins can be easily disintegrated, thereby improving the recyclability of materials constituting the structure of the cured product including the easily disintegrating resin composition. Attached Figure Description

[0046] Figure 1 This is a plan view representing an example of a rotor.

[0047] Figure 2 It means Figure 1 The cross-sectional view of the rotor is shown.

[0048] Figure 3 It means Figure 1 The enlarged cross-sectional view of the rotor is shown.

[0049] Figure 4 This is a cross-sectional view of an example motor in a direction perpendicular to the direction of rotation.

[0050] Figure 5 yes Figure 4 The diagram shows a longitudinal cross-section of the motor along its rotational axis.

[0051] Figure 6 It is Figure 4 The diagram shows an enlarged view of the groove periphery of the motor.

[0052] Figure 7 This is a cross-sectional schematic diagram representing an example of a power module. Detailed Implementation

[0053] In this specification, the expression "a~b" in the description of numerical ranges means "a" to "b" unless otherwise specified. For example, "1~5% mass" means "1% to 5% mass". Furthermore, the lower and upper limits of the numerical range can be arbitrarily combined with the lower and upper limits of other numerical ranges.

[0054] Unless otherwise specified, each ingredient and material listed in this instruction manual may be used alone or in combination with two or more.

[0055] The embodiments of the present invention will now be described in detail.

[0056] 1. Easily disintegrating resin compositions The easily disintegrating resin composition of this embodiment (hereinafter also simply referred to as the "resin composition") contains a thermosetting resin, and the bond strength ratio (S2 / S1) measured by the following steps is 0.30 or less.

[0057] step: The easily disintegrating resin composition was molded onto a copper substrate at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours to obtain a test piece.

[0058] The test piece will be used to determine the shear strength [N / mm] of the copper substrate at room temperature and a speed of 300 μm / s. 2 Set as S1[N / mm] 2 ].

[0059] Furthermore, after heating the test piece at 300°C for 30 minutes, the adhesion strength [N / mm] with the copper substrate was measured at room temperature at a speed of 300 μm / s. 2 Set as S2[N / mm] 2 ].

[0060] That is, it can be considered that the easily disintegrated resin composition of this embodiment, when heated, reduces the adhesion of its cured product to other materials, thus making it easier to peel off, separate, etc., and thereby making it easier to disintegrate the cured product.

[0061] In this embodiment, the seal strength ratio (S2 / S1) is 0.30 or less, preferably 0.25 or less, more preferably 0.20 or less, even more preferably 0.15 or less, and particularly preferably 0.05 or less. Furthermore, the seal strength ratio (S2 / S1) is preferably 0.01 or less, and may also be 0.00.

[0062] The adhesion strength (S2) measured through the above steps is preferably 3.0 N / mm, from the viewpoint of facilitating disassembly. 2 Below, 2.0 N / mm is preferred. 2 Hereinafter, 1.0 N / mm is further preferred. 2 The following is particularly preferred: 0.5 N / mm 2 the following.

[0063] There is no specific lower limit for the adhesion strength (S2), which can be achieved when the material has already peeled off from the copper substrate before the adhesion strength is measured. That is, it refers to the situation where the cured material of the test piece peels off from the copper substrate during heating at 300°C for 30 minutes. In this case, the adhesion strength (S2) is 0 N / mm. 2 The seal strength ratio (S2 / S1) also becomes 0.

[0064] From the viewpoint of obtaining good mechanical strength of the cured product, the adhesion strength (S1) measured through the above steps is preferably 8 N / mm². 2 The above is preferred, with 9 N / mm. 2 The above is further optimized to 10 N / mm. 2 The above is particularly preferred, with 12 N / mm. 2 above.

[0065] On the other hand, there is no particular upper limit to the sealing strength (S1), which can be set appropriately according to the application, for example, it can be 50 N / mm. 2 the following.

[0066] Furthermore, the cured product obtained by molding the easily disintegrating resin composition at 175°C, 6.9 MPa, and 120 seconds, and then post-curing it at 175°C for 4 hours, preferably has a linear expansion coefficient α2 of 46 ppm / °C or more in the temperature range of 190°C to 230°C, more preferably 50 ppm / °C or more, and even more preferably 55 ppm / °C or more.

[0067] Therefore, the solidified material is easy to peel off and separate from other materials, which improves its disintegration properties.

[0068] Furthermore, the cured product obtained by molding the easily disintegrating resin composition at 175°C, 6.9 MPa, and 120 seconds, and then post-curing it at 175°C for 4 hours, preferably has a linear expansion coefficient α3 of 80 ppm / °C or more, more preferably 100 ppm / °C or more, and even more preferably 200 ppm / °C or more in the temperature range of 250 to 260°C.

[0069] Therefore, the solidified material is easy to peel off and separate from other materials, which improves its disintegration properties.

[0070] In this embodiment, "ease of disintegration" refers to the ability of the cured product obtained by thermosetting the ease of disintegration resin composition of this embodiment to easily form cracks or to easily break or separate, thereby disintegrating. For example, the cured product of the ease of disintegration resin composition of this embodiment and the materials (such as sealed materials) within the cured product can be easily peeled off, thereby achieving ease of disintegration. That is, the cured product can be disintegrated even without applying excessive external stress that would overload the materials contained in the cured product or without chemical treatment such as using chemicals.

[0071] The easily disintegrating resin composition with the bonding strength of this embodiment can be achieved by selecting various components constituting the easily disintegrating resin composition and adjusting their contents. Specifically, examples include controlling the curability of the thermosetting resin (A) and curing agent (B), selecting the thermally expandable inorganic material (C) (described later), and adjusting the contents of the thermally expandable inorganic material (C), inorganic filler (D), and flame retardant.

[0072] The components contained in the resin composition of this embodiment will be described below.

[0073] [Thermosetting resin (A)] The resin composition of this embodiment contains a thermosetting resin (A).

[0074] Examples of thermosetting resins (A) include one or more selected from phenolic resins, epoxy resins, phenoxy resins, polyimide resins, benzoxazine resins, unsaturated polyester resins, melamine resins, silicone resins, cyanate ester resins, maleimide resins, cyanate ester resins, and acrylic resins. These thermosetting resins can utilize all monomers, oligomers, and polymers having two or more reactive functional groups within a single molecule, without particular limitations on their molecular weight or molecular structure.

[0075] The epoxy resins described above can be used with any monomers, oligomers, and polymers that have two or more epoxy groups in one molecule, and their molecular weight and molecular structure are not particularly limited.

[0076] Specifically, epoxy resins can be selected from phenolic varnish-type epoxy resins such as phenolic varnish-type epoxy resins and cresol varnish-type epoxy resins; bisphenol-type epoxy resins such as bisphenol A-type epoxy resins and bisphenol F-type epoxy resins; aromatic glycidylamine-type epoxy resins such as N,N-diglycidylaniline, N,N-diglycidyltoluidine, diaminodiphenylmethane-type glycidylamine, and aminophenol-type glycidylamine; hydroquinone-type epoxy resins; biphenyl-type epoxy resins; piracene-type epoxy resins; triphenol-methane-type epoxy resins; and triphenol-propane-type epoxy resins. Alkyl-modified triphenol methane-type epoxy resin; epoxy resin containing triazine core; dicyclopentadiene-modified phenol-type epoxy resin; naphthol-type epoxy resin; naphthalene-type epoxy resin; naphthylene ether-type epoxy resin; aralkyl-type epoxy resin with a phenylene skeleton and / or a biphenylene skeleton, aralkyl-type epoxy resin with a phenylene skeleton and / or a biphenylene skeleton, etc., or alicyclic epoxy resins such as vinylcyclohexene dioxide, dicyclopentadiene oxide, alicyclic dieoxy-adipate ester, etc., or one or more of the following alicyclic epoxy resins.

[0077] Among them, the thermosetting resin (A) is preferably an epoxy resin.

[0078] The content of the thermosetting resin (A) relative to the total amount of the resin composition is preferably 1% by mass or more and 50% by mass or less, more preferably 2% by mass or more and 30% by mass or less, and even more preferably 5% by mass or more and 20% by mass or less.

[0079] By setting the content of thermosetting resin (A) to the lower limit or above mentioned above, the flowability and moldability of the resin composition can be improved more effectively. Furthermore, by setting the content of thermosetting resin (A) to the upper limit or below mentioned above, the curability can be improved, resulting in a good cured product.

[0080] [Curing agent (B)] The curing agent (B) in this embodiment can be selected according to the type of thermosetting resin (A), and there are no particular limitations as long as it can react with it. Specifically, examples of curing agents (B) include addition-polymerization type curing agents, catalytic type curing agents, and condensation type curing agents.

[0081] Specifically, curing agents (B) can include phenolic curing agents, amines, polyhydroxystyrene such as poly(p-hydroxystyrene), alicyclic anhydrides such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA), trimellitic anhydride (TMA), pyromellitic dianhydride (PMDA), benzophenone tetracarboxylic dianhydride (BTDA), polysulfides, thioesters, thioethers and other polythiol compounds, isocyanate prepolymers, isocyanate compounds such as end-capped isocyanates, and organic acids such as carboxylic acid-containing polyester resins.

[0082] Specifically, phenolic curing agents can be selected from phenolic varnish resins such as phenol-formaldehyde resins, cresol-formaldehyde resins, naphthol-formaldehyde resins, aminotriazine-formaldehyde resins, phenolic resins, and triphenylmethane-type phenol-formaldehyde resins; modified phenolic resins such as terpene-modified phenolic resins and dicyclopentadiene-modified phenolic resins; aralkyl resins such as phenolic aralkyl resins having a phenylene skeleton and / or a biphenylene skeleton, and naphthol aralkyl resins having a phenylene skeleton and / or a biphenylene skeleton; bisphenol compounds such as bisphenol A and bisphenol F; and methyl-type phenolic resins, etc., one or more of these. Furthermore, from the viewpoint of curability, the hydroxyl equivalent of the phenolic resin-based curing agent is preferably, for example, 90 g / eq or more and 250 g / eq or less.

[0083] Specifically, examples of the aforementioned amines include, for instance, polyamine compounds selected from aliphatic polyamines such as diethylenetriamine (DETA), triethylenetetramine (TETA), and m-phenylenediamine (MXDA); aromatic polyamines such as diaminodiphenylmethane (DDM), m-phenylenediamine (MPDA), and diaminodiphenyl sulfone (DDS); and polyamine compounds such as dicyandiamide (DICY) and organic acid dihydrazides; and one or more acid anhydrides such as hexahydrophthalic anhydride (HHPA) and methyltetrahydrophthalic anhydride (MTHPA), and aromatic acid anhydrides such as trimellitic anhydride (TMA), pyromellitic dianhydride (PMDA), and benzophenone tetracarboxylic dianhydride (BTDA).

[0084] In this embodiment, when epoxy resin is used as the thermosetting resin (A), a combination of phenolic curing agents is preferred as the curing agent (B).

[0085] The content of the curing agent (B) relative to 100 parts by weight of the thermosetting resin (A) is preferably 5 to 50 parts by weight, more preferably 10 to 30 parts by weight.

[0086] Furthermore, the contents of the thermosetting resin (A) and the curing agent (B) can be appropriately set according to the thermosetting resin (A) and the curing agent (B). For example, the phenolic curing agent (B) and the epoxy resin (A) can be adjusted such that the equivalent ratio (EP) / (OH) of the number of epoxy groups (EP) in all thermosetting resins to the number of phenolic hydroxyl groups (OH) in all phenolic resins is preferably 0.8 to 1.6 or less, more preferably 0.9 to 1.3 or less, and even more preferably 1.0 to 1.2 or less. When the equivalent ratio is within the above range, the curing characteristics of the resin composition of this embodiment can be improved.

[0087] The resin composition of this embodiment may also contain the following components.

[0088] [Thermal Expansion Inorganic Materials (C)] Thermally expandable inorganic material (C) refers to an inorganic material that can undergo a phase change upon heating, thereby causing volume expansion. By using thermally expandable inorganic material (C), the cured resin composition of this embodiment can be easily disintegrated upon heating. That is, the thermally expandable inorganic material (C) dispersed inside the cured material expands in volume upon heating, thus breaking down the cured material from the inside, thereby enabling the cured material to be easily disintegrated.

[0089] Examples of thermally expandable inorganic materials (C) include one or more selected from crystalline silicon dioxide, crystalline aluminum phosphate, and their derivatives.

[0090] The aforementioned crystalline silica (SiO2) possesses quartz-type, tridymite-type, and leucosite-type crystal structures. Furthermore, similar to crystalline silica, crystalline aluminum phosphate also possesses blocky aluminate-type, tridymite-type, and crystallite-type crystal structures, corresponding to the crystal structures of silica, respectively. Triclinone is a leucosite-type silica with SiO2... 4+ A portion was replaced with Al 3+ Na + What was obtained was a derivative of crystalline silica (white silica).

[0091] Both crystalline silica and crystalline aluminum phosphate undergo α-β phase transitions at specific temperatures within their respective crystal structures, resulting in volume expansion. For example, it is known that leucosite-type silica undergoes α-β phase transitions in the temperature range of 200℃–250℃, tridymite-type silica in the range of 120℃–200℃, boehmite-type aluminum phosphate in the range of 550–600℃, and crystallite-type aluminum phosphate in the range of 300–350℃, thus expanding in volume. Furthermore, there are also cases where volume expansion occurs through transformations between crystal structures under specified conditions, such as heating.

[0092] The choice of which crystal structure the thermally expandable inorganic material (C) to use can be made from the perspectives of the heating temperature required for volume expansion, the expansion rate, and the transformation rate. Furthermore, the thermally expandable inorganic material (C) in this embodiment can also be a mixture of thermally expandable inorganic materials with different crystal structures.

[0093] In this embodiment, the thermally expandable inorganic material (C) is preferably white silica-type silica or tridymite-type silica from the viewpoint that it can be easily disintegrated at low temperatures. From the viewpoints of availability and ease of processing, white silica-type silica is more preferred.

[0094] The content of the thermally expandable inorganic material (C) relative to the total amount of the resin composition is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 20% by mass or more, and particularly preferably 40% by mass or more. This improves the disintegration resistance generated by heating.

[0095] The content of the thermally expandable inorganic material (C) relative to the total amount of the resin composition is preferably 98% by mass or less, more preferably 90% by mass or less, and even more preferably 80% by mass or less. This allows for good formability of the cured product.

[0096] [Inorganic filler material (D)] The resin composition of this embodiment may contain inorganic filler material (D) other than the thermally expandable inorganic material (C) described above.

[0097] Inorganic filler materials (D) can be used to improve mechanical strength or impart heat resistance, flame retardancy, etc., depending on the intended use of the cured material.

[0098] As inorganic filler materials (D), examples include silicates such as talc, calcined clay, uncalcined clay, mica, and glass; oxides such as fused silica, spherical silica, crushed silica, titanium dioxide, and boehmite; carbonates such as calcium carbonate, magnesium carbonate, and hydrotalcite; hydroxides such as aluminum hydroxide, magnesium hydroxide, and calcium hydroxide; sulfates or sulfites such as barium sulfate, calcium sulfate, and calcium sulfite; borates such as zinc borate, barium metaborate, aluminum borate, calcium borate, and sodium borate; nitrides such as aluminum nitride, boron nitride, silicon nitride, and carbon nitride; and titanates such as strontium titanate and barium titanate. These can be used individually or in combination with two or more.

[0099] The average particle size D50 of the inorganic filler material (D) is preferably 0.01 μm or more, more preferably 0.5 μm or more, and even more preferably 1 μm or more. This improves strength.

[0100] On the other hand, the average particle size D50 of the inorganic filler material (D) is preferably 75 μm or less, more preferably 40 μm or less, even more preferably 20 μm or less, particularly preferably 10 μm or less, and even more particularly preferably 8 μm or less.

[0101] Furthermore, by keeping the average particle size of the inorganic filler within the aforementioned range, the filling performance is improved. The average particle size D50 can be the volume-converted (cumulative 50%) average particle size obtained using a commercially available laser particle size analyzer.

[0102] Furthermore, the particle size distribution of the inorganic filler material (D) based on volume obtained using a laser particle size analyzer can have more than two peaks. In other words, it is preferable to have an inorganic filler material (D) containing two or more different particle sizes. As a result, smaller particles can easily enter between larger particles, thus improving filling performance.

[0103] The content of inorganic filler (D) can be appropriately set according to the application, and is preferably 1 to 45% by mass relative to the total amount of resin composition, more preferably 10 to 40% by mass, and even more preferably 20 to 35% by mass.

[0104] By setting the content of inorganic filler (D) to the lower limit or above mentioned above, the shelf life and curability of the cured product can be improved. Furthermore, by setting the content of inorganic filler (D) to the upper limit or below mentioned above, easy disintegration and good flowability of the resin composition can be obtained, and the moldability can be effectively improved.

[0105] [Coupled agent] The resin composition of this embodiment may contain a coupling agent when it contains a thermally expandable inorganic material (C) or an inorganic filler (D). This suppresses the aggregation of the thermally expandable inorganic material (C) and the inorganic filler (D), thereby achieving good flowability.

[0106] As coupling agents, various known coupling agents such as epoxysilanes, mercaptosilanes, aminosilanes, alkylsilanes, ureosilanes, vinylsilanes, titanium compounds, aluminum chelates, and aluminum / zirconium compounds can be used.

[0107] More specifically, examples include vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltriethoxysilane, vinyltriacetoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-aminopropyltrimethoxysilane. γ-Triethoxysilane, γ-Anilinepropyltrimethoxysilane, γ-Anilinepropylmethyldimethoxysilane, γ-[bis(β-hydroxyethyl)]aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane, γ-(β-aminoethyl)aminopropyldimethoxymethylsilane, N-(trimethoxysilylpropyl)ethylenediamine, N-(dimethoxymethylsilylisopropyl)ethylenediamine, Silane coupling agents such as methyltrimethoxysilane, dimethyldimethoxysilane, methyltriethoxysilane, N-β-(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane, hexamethylethoxysilane, vinyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-acryloyloxypropyltrimethoxysilane, and hydrolysate of 3-(triethoxysilyl)-N-(1,3-dimethylbutylene)propylamine; isopropyl triisostearate titanate, isopropyl tri(dioctyl pyrophosphate) titanate, isopropyl tri(N-aminoethyl- Titanium ester coupling agents include aminoethyl titanate, tetraoctyl bis(di-tetrazyl phosphate) titanate, tetra(2,2-diallyloxymethyl-1-butyl)bis(di-tetrazyl) phosphite titanate, bis(dioctyl pyrophosphate) oxyacetic acid titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctyl ester titanate, isopropyl dimethacrylate isostearyl titanate, isopropyl tri-dodecylbenzenesulfonyl titanate, isopropyl isostearyl diacrylate titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, and tetraisopropyl di(dioctyl phosphite) titanate. These can be used individually or in combination of two or more.

[0108] The content of the coupling agent is not particularly limited, but is preferably 0.05% by mass or more and 3% by mass or less relative to the total resin composition, and more preferably 0.1% by mass or more and 2% by mass or less.

[0109] By setting the content of the coupling agent to the lower limit or above mentioned above, the dispersibility of the inorganic filler in the resin composition can be improved. Furthermore, by setting the content of the coupling agent to the upper limit or below mentioned above, the flowability of the resin composition can be improved, thereby enhancing its moldability.

[0110] [Curing Accelerator] The resin composition of this embodiment may contain a curing accelerator.

[0111] Curing accelerators are typically substances that promote the reaction between thermosetting resins (A) and curing agents (B).

[0112] Specifically, examples of curing accelerators include phosphorus-containing compounds such as organophosphorus compounds, tetrasubstituted phosphonium compounds, phosphate betaine compounds, adducts of phosphonium compounds and quinone compounds, or adducts of phosphonium compounds and silane compounds; amidine compounds such as 1,8-diazabicyclo(5,4,0)undecene-7 and imidazole; nitrogen-containing compounds such as tertiary amines such as benzyl dimethylamine, amidine salts or ammonium salts; and phenolic compounds such as phenol, bisphenol A, nonylphenol, and 2,3-dihydroxynaphthalene.

[0113] Furthermore, examples of the aforementioned organophosphines include triphenylphosphine, tri-p-tolylphosphine, tetraphenylphosphonium-tetraphenylborate, triphenylphosphine-triphenylborane, and 1,2-bis-(diphenylphosphino)ethane. These can be used individually or in combination with two or more.

[0114] The content of the curing accelerator can be appropriately set according to the application, and is preferably 0.1 to 5% by mass relative to the total amount of the resin composition, more preferably 0.2 to 3% by mass.

[0115] By setting the content of the curing accelerator to the lower limit or above mentioned above, the resin composition can be easily cured appropriately. On the other hand, by setting the content of the curing accelerator to the upper limit or below mentioned above, the melt state can be prolonged, thereby further prolonging the low viscosity state.

[0116] [Cyclic compounds containing hydroxyl groups] The resin composition of this embodiment, when containing a curing accelerator, may contain a compound in which hydroxyl groups are bonded to two or more adjacent carbon atoms constituting an aromatic ring (hereinafter also referred to as "hydroxyl-containing cyclic compounds"). Therefore, even when using a phosphorus-containing curing accelerator that does not have latency as the curing accelerator, the reaction during melt mixing of the resin composition can be suppressed, thereby stably obtaining the resin composition. Furthermore, the hydroxyl-containing cyclic compounds also have the effect of reducing the melt viscosity of the resin composition and improving its flowability.

[0117] As hydroxyl-containing cyclic compounds, monocyclic compounds represented by the following general formula (5) or polycyclic compounds represented by the following general formula (6) can be used. These compounds may have substituents other than hydroxyl groups. In general formula (5), either R15 or R19 is a hydroxyl group, and the other is a hydrogen atom, a hydroxyl group, or a substituent other than a hydroxyl group. Furthermore, R16, R17, and R18 are hydrogen atoms, hydroxyl groups, or substituents other than a hydroxyl group. In general formula (6), either R20 or R26 is a hydroxyl group, and the other is a hydrogen atom, a hydroxyl group, or a substituent other than a hydroxyl group. Furthermore, R21, R22, R23, R24, and R25 are hydrogen atoms, hydroxyl groups, or substituents other than a hydroxyl group.

[0118] Specific examples of monocyclic compounds represented by general formula (5) include, for example, catechol, pyrogallol, gallic acid, gallic acid esters or their derivatives.

[0119] Furthermore, specific examples of polycyclic compounds represented by general formula (6) include 1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, and their derivatives. Among these, compounds in which hydroxyl groups are bonded to two adjacent carbon atoms constituting the aromatic ring are preferred from the viewpoint of easy control of flowability and curability. Furthermore, considering volatilization during the mixing process, compounds with a naphthalene ring as the core with low volatility and high weighing stability are more preferred. In this case, specifically, hydroxyl-containing cyclic compounds can be, for example, compounds with a naphthalene ring such as 1,2-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, and their derivatives. These hydroxyl-containing cyclic compounds can be used alone or in combination of two or more.

[0120] The content of the hydroxyl-containing cyclic compound, relative to 100% by mass of the total resin composition, is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, and even more preferably 0.05% by mass or more. When the content of the hydroxyl-containing cyclic compound is within the above range, sufficient reduction in viscosity and improvement in flowability of the resin composition can be achieved. Furthermore, the content of the hydroxyl-containing cyclic compound, relative to 100% by mass of the total resin composition, is preferably 2% by mass or less, more preferably 0.8% by mass or less, and even more preferably 0.5% by mass or less. When the content of the hydroxyl-containing cyclic compound is within the above range, the possibility of a decrease in the curability of the resin composition or a decrease in the physical properties of the cured product is small.

[0121] Furthermore, the resin composition of this embodiment may also contain, for example, flame retardants; colorants such as carbon black; release agents such as natural waxes, synthetic waxes, higher fatty acids or their metal salts, paraffin wax, and oxidized polyethylene; low-stress agents such as silicone oil and silicone rubber; ion trapping agents such as hydrotalcite or hydrated oxides of elements selected from magnesium, aluminum, bismuth, titanium, and zirconium; binding agents such as thiazoline, diazole, triazole, triazine, and pyrimidine; antioxidants and other additives.

[0122] Inorganic flame retardants can be cited as examples of the aforementioned flame retardants.

[0123] Specific examples of inorganic flame retardants include aluminum hydroxide, magnesium hydroxide, zinc borate, zinc molybdate, phosphazene, and carbon black. One or more of these specific examples can be used as flame retardants. From the viewpoint of achieving both flame retardancy and easy disintegration, aluminum hydroxide is preferred.

[0124] Furthermore, aluminum hydroxide decomposes upon exposure to high temperatures. Therefore, when a structure using the resin composition of this embodiment containing aluminum hydroxide is heated to 200°C or higher, the structure can be destroyed from the inside by the dehydration and decomposition of aluminum hydroxide, thereby making the structure easily disintegrate.

[0125] The lower limit of the aluminum hydroxide content relative to the total amount of the resin composition is preferably 1% by mass or more from the viewpoint of obtaining flame retardancy, and preferably 40% by mass or more from the viewpoint of obtaining both flame retardancy and easy disintegration, and more preferably 50% by mass or more.

[0126] On the other hand, the upper limit of the aluminum hydroxide content can be appropriately set according to the application of the resin composition, for example, it can be below 60% by mass.

[0127] Furthermore, from the viewpoint of obtaining the disintegration property generated by aluminum hydroxide while maintaining good moldability of the resin composition, the total content of thermally expandable inorganic material (C), inorganic filler material (D) and aluminum hydroxide, relative to the total amount of the resin composition, is preferably 60 to 95% by mass, more preferably 70 to 90% by mass, and even more preferably 75 to 85% by mass.

[0128] [Method for manufacturing the resin composition] Next, the method for manufacturing the resin composition of this embodiment will be described.

[0129] The method for manufacturing the resin composition in this embodiment is not particularly limited. For example, the thermosetting component and other arbitrary components can be mixed using a mixer or similar equipment, and then melt-heated and kneaded at approximately 90–120°C using a heated kneader, hot roller, or extruder. Next, the obtained mixture is cooled and pulverized to obtain a powdered or granular resin composition. The resin composition can be pressed into tablets after pulverization, or it can be pulverized into sheets, for example, through vacuum lamination or compression molding.

[0130] Furthermore, for example, a varnish-like resin composition can be prepared by dissolving, mixing, and stirring the thermosetting component and other arbitrary components in a solvent using various mixers such as ultrasonic dispersion, high-pressure impact dispersion, high-speed rotational dispersion, bead milling, high-speed shear dispersion, or rotational-revolutionary dispersion.

[0131] Specifically, solvents include acetone, methyl ethyl ketone, methyl isobutyl ketone, toluene, ethyl acetate, heptane, cyclohexane, cyclohexanone, tetrahydrofuran, dimethylformamide, dimethylacetamide, dimethyl sulfoxide, ethylene glycol, cellosol, carbitol, anisole, and N-methylpyrrolidone. A single solvent can be used, or two or more can be used in combination.

[0132] 2. Structure The structure of this embodiment includes a cured product of the above-described easily disintegrating resin composition. The cured product can be obtained by heat curing the resin composition of this embodiment at 100-200°C for 10-900 seconds.

[0133] As a structural component, it can be widely used in composite components for transportation equipment such as automobiles, railways, ships, and aircraft; semiconductor chips; semiconductor elements; semiconductor devices including printed wiring boards; composite components for factory equipment such as work robots; circuit display devices; information and communication terminals; electronic devices such as light-emitting diodes, physical batteries, and chemical batteries; composite components for civil engineering and construction; and composite components for sports and entertainment. Among these, composite components for transportation equipment such as automobiles and semiconductor devices are preferred from the viewpoint of addressing environmental issues. Specifically, a semiconductor device can include a semiconductor element and a sealing material that seals the semiconductor element, wherein the sealing material is a cured product of the resin composition of this embodiment. The sealing method is not particularly limited, and known methods can be used.

[0134] Specifically, it is preferably applied to rotors, stators, and power modules. Details will be provided later.

[0135] <Rotor> The rotor of this embodiment comprises a cured product of the above-described easily disintegrating resin composition. The cured product can be obtained by heat curing the resin composition of this embodiment at 100–200°C for 10–900 seconds.

[0136] Hereinafter, an example of the rotor of this embodiment will be described.

[0137] Figure 1 This is a plan view showing the rotor 100 according to this embodiment. Figure 2 It means Figure 1 The cross-sectional view of rotor 100 is shown. Additionally, Figure 1 and Figure 2 This is a schematic diagram showing the rotor 100. The structure of the rotor 100 involved in this embodiment is not limited to... Figure 1 and Figure 2 The structure shown.

[0138] The rotor 100 includes a rotor core 110, a magnet 120, and a fixing member 130. A hole 150 is provided in the rotor core 110. The magnet 120 is inserted into the hole 150. The fixing member 130 is provided in the spacer 140 between the hole 150 and the magnet 120.

[0139] The fixing component 130 is formed using the above-described easily disintegrating resin composition.

[0140] The rotor 100 described in this embodiment is, for example, a motor mounted in an automobile. The motor includes a rotor 100 and a stator disposed around the rotor 100. The stator consists of a stator core and coils wound around the stator core.

[0141] like Figure 2 As shown, rotor 100 is mounted on rotating shaft 170. The rotation generated by rotor 100 is transmitted to the outside via rotating shaft 170.

[0142] A through hole is provided in the rotor core 110 for inserting the rotating shaft 170. The rotor core 110 is fixedly mounted on the rotating shaft 170 inserted into the through hole. The shape of the rotor core 110 is not particularly limited, and may be circular or polygonal when viewed from above.

[0143] like Figure 2 As shown, the rotor core 110 is formed by stacking multiple electromagnetic steel plates 112, which are thin-plate magnetic bodies. The electromagnetic steel plates 112 are made of, for example, iron or an iron alloy.

[0144] And, as Figure 2As shown, end plates 118a and 118b are provided at both ends of the rotor core 110 along its axial direction. That is, end plate 118a is provided on top of the stacked electromagnetic steel plate 112, and end plate 118b is provided below the stacked electromagnetic steel plate 112. End plates 118a and 118b can be fixed to the rotating shaft 170, for example, by welding.

[0145] Figure 3 It means Figure 1 An enlarged cross-sectional view of the rotor 100 is shown. (As shown...) Figure 3 As shown, riveting portions 160 are formed on multiple electromagnetic steel plates 112. The riveting portions 160 are, for example, protrusions formed on the electromagnetic steel plates 112. The electromagnetic steel plates 112 are joined together by the riveting portions 160.

[0146] Furthermore, the end plate 118a is provided with a groove 116 for example to avoid interference with the riveting portion 160 protruding from the electromagnetic steel plate 112 or the fixing member 130 protruding onto the electromagnetic steel plate 112.

[0147] Furthermore, the fixing member 130 protruding onto the electromagnetic steel plate 112 is formed by curing the easily disintegrating resin composition remaining on the electromagnetic steel plate 112 when the aforementioned easily disintegrating resin composition is injected into the spacer portion 140.

[0148] like Figure 1 As shown, a plurality of holes 150 are provided in the rotor core 110. The plurality of holes 150 are arranged in the rotor core 110 in a point-symmetrical manner with the axis of rotation 170 as the center.

[0149] like Figure 1 As shown, in the rotor 100 of this embodiment, for example, multiple groups of holes formed by two adjacent holes 150 are arranged along the periphery of the rotation shaft 170. The multiple groups of holes are arranged, for example, spaced apart from each other. The two holes 150 constituting one group are, for example, arranged in a V-shape when viewed from above. In this case, the two holes 150 constituting one group are arranged, for example, with their respective ends facing each other on the side of the rotation shaft 170. Furthermore, the two holes 150 constituting one group are, for example, spaced apart from each other.

[0150] <Stator> The stator of this embodiment comprises a cured product of the above-described easily disintegrating resin composition. The cured product can be obtained by heat curing the resin composition of this embodiment at 100–200°C for 10–900 seconds.

[0151] Figure 4 A schematic cross-sectional view of motor 101 in a direction perpendicular to the direction of rotation axis. Figure 5A schematic cross-sectional view of the motor 101 along its rotation axis. Figure 6 It is to surround the groove ( Figure 4 The diagram (X) is enlarged and schematically shows a cross-sectional view of the portion of coil 9 protruding from the end of slot 8.

[0152] The motor 101 includes a housing 1 and a rotor 2, a stator 4 and a coil 9 housed inside the housing 1.

[0153] The housing 1 has a cylindrical portion 1a and side plate portions 1b and 1c that close the axial ends of the cylindrical portion 1a. As the material of the housing 1, for example, aluminum alloy (casting), resin material, or a combination thereof can be used.

[0154] like Figure 4 As shown, rotor 2 is housed inside housing 1. Figure 5 As shown, a rotating shaft 3 is mounted at the center of the rotor 2 as an output shaft. The two ends of the rotating shaft 3 are supported by bearings 3a on the side plates 1b and 1c, respectively. Thus, the rotor 2 can rotate around the rotating shaft 3.

[0155] A permanent magnet 5 is installed inside the rotor 2. Specifically, as follows: Figure 4 As shown, multiple (eight in this case) permanent magnets 5 are arranged at equal intervals on the same circumference. At this time, the magnetic poles of adjacent permanent magnets 5 are set to be different from each other.

[0156] like Figure 5 As shown, a cylindrical stator 4 is arranged and fixed on the inner circumference side of the cylindrical portion 1a in a manner that surrounds the outer circumference of the rotor 2. A small gap (air gap) is provided between the inner circumferential surface of the stator 4 and the outer circumferential surface of the rotor 2.

[0157] The stator core 41 is configured to stack multiple electromagnetic steel plates axially and fix them tightly together, such as... Figure 4 As shown, when viewed from the axial end, a magnetic yoke 6 is provided in a ring shape, and a plurality of teeth 7 extend from the magnetic yoke 6 toward the rotor 2 (inner circumferential side). The plurality of teeth 7 are arranged at equal intervals in the circumferential direction. Here, as... Figure 4 As shown, 24 teeth 7 are provided. Grooves 8 are provided between each tooth 7. Furthermore, a resin layer 50, which is surrounded and covered by a resin composition to form a thin wall, is provided on each tooth 7.

[0158] The coil 9 is U-shaped with a flat angle and is wound in a manner that allows it to be housed in two slots 8 spaced apart by the cross teeth 7. Here, the coil 9 is housed in the bushing member 20 disposed in the slots 8 in a distributed winding manner. Figure 4The coil 9 has a first coil end and a second coil end. The first coil end protrudes axially to one side of the stator core 41. The second coil end protrudes axially to the other side of the stator core 41. That is, the coil 9 has a pair of coil ends protruding axially to both sides of the stator core 41, respectively.

[0159] Coil 9 is constructed, for example, using a wire made by forming conductors such as copper, aluminum, and iron into filaments.

[0160] The teeth 7 are provided corresponding to the permanent magnets 5 of the rotor 2. By sequentially energizing each coil 9, the rotor 2 rotates through the attraction and repulsion between the coil and the corresponding permanent magnet 5.

[0161] The tooth 7 is formed such that its circumferential width is large on the outer circumferential side and small on the inner circumferential side, tapering towards the front end on the inner circumferential side. At the end of the tooth 7 on the inner circumferential side, a tooth front end 71 is formed that is circumferentially opposite to the tooth 7 in a manner that reduces the width of the groove 8.

[0162] Groove 8 is the space between adjacent teeth 7, such as Figure 6 As shown, the toothed portions 7 are arranged such that the wall surfaces 72 of the radially opposite teeth 7 are parallel to each other. The front ends 71 ​​of the teeth form an inner circumferential opening of the groove 8. The groove 8 includes: a plurality of coils 9 disposed on the outer circumferential side (the side of the yoke 6); and a resin sealing portion 65 disposed on the inner circumferential side (the side of the front ends 71 ​​of the teeth).

[0163] like Figure 6 As shown, the resin sealing part 65 is provided on the inner circumferential side of the groove 8 (on the front end 71 side of the tooth). The resin sealing part 65 can be provided by embedding molding or as a separate part.

[0164] The resin material used in the resin sealing part 65 is the aforementioned easily disintegrating resin composition.

[0165] In one embodiment, the resin sealing portion 65 is configured to cover the coil 9 only within the groove 8.

[0166] In another embodiment, the resin sealing portion 65 is configured to cover the coil 9 within the groove 8, and to cover one of the pair of coil ends; in other words, only either the first coil end or the second coil end is covered.

[0167] In another embodiment, the resin sealing portion 65 is configured to cover the coil 9 within the groove 8, and to cover both ends of a pair of coils, in other words, to cover both the first coil end and the second coil end.

[0168] <Power Module> Figure 7 This is a cross-sectional view showing the structure of the power module (semiconductor device) 100 in this embodiment. Figure 7 The power module 100 shown includes: a semiconductor element 21 mounted on a substrate 30; and a sealing material 51 formed by sealing the semiconductor element 21.

[0169] As substrate 30, a lead frame is used. The lead frame is made of metal, for example, copper.

[0170] Semiconductor element 21 is a power semiconductor element, preferably a power semiconductor element that satisfies any one of the following conditions (a) to (d).

[0171] (a) Semiconductor components that consume 2.0W or more of electrical power (b) A semiconductor device composed of one or more semiconductors selected from SiC, GaN, Ga2O3 and diamond. (c) Semiconductor devices with a voltage of 1.0V or higher (d) Power density is 10 W / cm² 3 The above semiconductor components The power consumption of semiconductor element 21 is, for example, 2.0W or more under condition (a) above, preferably 3.0W or more, and for example, 4.0W or less. The voltage of semiconductor element 21 is, for example, 1.0V or more under condition (c) above, preferably 3.0V or more, and for example, 5.0V or more. Furthermore, the voltage of semiconductor element 21 can be, for example, 100V or less. Furthermore, the power density of semiconductor element 21 is, for example, 10W / cm² under condition (d) above. 3 The above is preferably 20W / cm. 3 The above, and for example, can be 30W / cm 3 That's all. Furthermore, the power density of the semiconductor element 21 can, for example, be 200 W / cm². 3 Furthermore, the semiconductor element 21 can operate in high-temperature environments, such as above 200°C, preferably above 260°C.

[0172] Semiconductor element 21 is preferably a power semiconductor element disposed on substrate 30, including one or more electronic components selected from rectifier diodes, power transistors, power MOSFETs, insulated gate bipolar transistors (IGBTs), thyristors, gate turn-off thyristors (GTOs), and bidirectional thyristors.

[0173] Semiconductor element 21 is mounted on chip pad 32 in substrate 30 and electrically connected to external lead 34 via wire 40.

[0174] The sealing material 51 seals the semiconductor element 21 by covering the side opposite to the side opposite to the substrate 30. In this embodiment, the sealing material 51 is composed of a cured product of the aforementioned easily disintegrating resin composition. The sealing material 51 can be formed, for example, by sealing the easily disintegrating resin composition using known methods such as transfer molding or compression molding.

[0175] 3. Disassembly Method The method for dismantling the structure in this embodiment includes a step of heating the structure to 200°C or higher to dismantle the cured product of the easily disintegratable resin composition.

[0176] Because the solidified material can be broken down by heating, there is no need for mechanical equipment to destroy the solidified material, and it can suppress pollution and corrosion that would occur when using chemicals.

[0177] The heating temperature can be appropriately set according to the type of thermally expandable inorganic material (C), etc. From the viewpoint of improving disintegration, it is preferably 250°C or higher, more preferably 300°C or higher. Depending on the application of the structure, and from the viewpoint of shortening the time until disintegration, the temperature can be further increased. Specifically, in the case of a rotor, in order to correspond to the demagnetization of the magnet, it can be 350°C or higher.

[0178] On the other hand, from the viewpoint of reducing the thermal load and environmental load on the structure, the heating temperature is preferably below 600°C, and more preferably below 500°C.

[0179] There are no particular restrictions on the heating method; any known method may be used.

[0180] 4. Recycling methods The recycling method of this embodiment is a method for recycling the material constituting the above-described structure, which includes: a step of heating the structure to 200°C or higher to disintegrate the cured product of the easily disintegrating resin composition; and a step of recycling the material from the structure.

[0181] Therefore, the materials used in the structure can be reused. The process of disintegrating the solidified material is the same as the method described in the disintegration method above.

[0182] Furthermore, there are no particular limitations on the method of recycling materials from a structure, as long as it does not reduce the quality of the materials. For example, a method of recycling materials can be given by destroying the structure together with the solidified material that has become brittle through disassembly.

[0183] When the structure is a rotor, there are no particular limitations on the materials that can be recycled from the rotor, as long as they are heat-resistant. Examples include metals (electromagnetic steel plates) and permanent magnets.

[0184] When the structure is a stator, there are no particular restrictions on the materials recycled from the stator, as long as they are heat-resistant. Examples include coils and metals (electromagnetic steel plates).

[0185] When the structure is a power module, there are no particular limitations on the materials recycled from the power module, as long as they are heat-resistant; for example, metal lead frames can be used.

[0186] The embodiments of the present invention have been described above, but these are merely examples of the present invention, and various configurations other than those described above may also be used.

[0187] Example Next, the present invention will be described in detail through embodiments, but the content of the present invention is not limited to the embodiments.

[0188] <Preparation of Resin Compositions> Using the raw materials shown below, the components were mixed in the solid component ratios shown in Table 1 to obtain a mixture. Mixing was carried out at room temperature using a Henschel mixer. The obtained mixture was then rolled at 90–120°C to obtain a compound. After cooling the obtained compound, it was pulverized to obtain the respective resin compositions.

[0189] [raw material] (Thermosetting resin (A)) • Epoxy Resin 1: Phenolic aralkyl type epoxy resin containing a biphenyl backbone (manufactured by Nippon Kayaku Co., Ltd., NC3000) (Curing agent (B)) • Curing agent 1: Phenolic aralkyl resin containing a biphenyl backbone (manufactured by Meiwa Plastic Industries, Ltd., MEH-7851SS) • Curing agent 2: Phenolic aralkyl resin containing a biphenyl backbone (manufactured by Nippon Kayaku Co., Ltd., GPH-65) (Thermal expansion of inorganic materials (C)) • Thermally expandable inorganic material 1: White silica type silica (white silica manufactured by Micron) (Inorganic filler material (D)) • Inorganic filler material 1: fused spherical silica TS-6026, manufactured by Micron (average particle size D50: 9μm) • Inorganic filler material 2: Molten spherical silica SC-2500-SQ, manufactured by ADMATECHSCOMPANY LIMITED (average particle size D50: 0.6μm) • Inorganic filler material 3: Fused spherical silica SC-5500-SQ, manufactured by ADMATECHSCOMPANY LIMITED (average particle size D50: 1.6μm) (Curing accelerator) • Curing Accelerator 1: Tetraphenylphosphonium bis(naphthalene-2,3-dioxy)phenylsilicate (other) • Colorant: Carbon black (manufactured by Mitsubishi Chemical Corporation, Carbon Black #5) • Coupling agent: N-phenyl-3-aminopropyltrimethoxysilane (manufactured by Dow Corning Toray Co., Ltd., CF-4083) • Release agent: Synthetic wax (manufactured by Clariant Chemicals Japan KK, WE-4) • Low-stress agent: Silicone oil (manufactured by Dow Corning Toray Co., Ltd., FZ-3730) • Ion scavenger: Magnesium hydroxide, magnesium carbonate, hydrate (manufactured by Kyowa Chemical Industry Co., Ltd., DHT-4H) • Flame retardant: Aluminum hydroxide (manufactured by Sumitomo Chemical Co., Ltd., CL-303) <Evaluation, Measurement> (1) Adhesion strength The obtained easily disintegrating resin compositions were molded onto a copper substrate (a copper substrate obtained by Cu plating on a copper plate manufactured by Furukawa Electric Co., Ltd. under the conditions of 175°C, 6.9 MPa, and 120 seconds) and then post-cured at 175°C for 4 hours to obtain test pieces.

[0190] The test piece will be used to determine the shear strength [N / mm] of the copper substrate at room temperature and a speed of 300 μm / s. 2 Set as S1[N / mm] 2 ].

[0191] Furthermore, after heating the test piece at 300°C for 30 minutes, the adhesion strength [N / mm] with the copper substrate was measured at room temperature at a speed of 300 μm / s. 2 Set as S2[N / mm] 2 ].

[0192] The results are shown in Table 1.

[0193] (2) TMA determination (glass transition temperature, coefficient of linear expansion) The obtained easily disintegrating resin compositions were molded onto a copper substrate at 175°C, 10 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours to obtain test pieces.

[0194] Using this test piece, measurements were performed using a thermomechanical analysis apparatus (Seiko Instruments Inc., TMA / SS6000) within the measurement temperature range of 25°C to 320°C at a heating rate of 5°C / min. Based on the measurement results, the glass transition temperature Tg (°C) was calculated. α1 is the coefficient of linear expansion from 40°C to 80°C, α2 is the coefficient of linear expansion from 190°C to 230°C, and α3 is the coefficient of linear expansion from 250°C to 260°C.

[0195] (3) Easily disintegrated The obtained easily disintegrating resin compositions were molded onto a nickel plate at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours to obtain test pieces.

[0196] Then, the test piece was heated at 300°C for 30 minutes, cooled to room temperature, and its disintegration was evaluated according to the following criteria.

[0197] (Benchmark) ○: The cured material on the test piece peels off from the nickel plate.

[0198] ×: The solidified material on the test piece did not peel off from the nickel plate.

[0199] [Table 1] This application claims priority based on Japanese Patent Application No. 2023-040608, filed on March 15, 2023, the entire contents of which are incorporated herein by reference.

[0200] Explanation of reference numerals in the attached figures 1. Housing, 1a. Cylindrical section, 1b. Side plate section, 2. Rotor, 3. Rotating shaft, 3a. Bearing, 4. Stator, 5. Permanent magnet, 6. Yoke section, 7. Tooth section, 8. Slot, 9. Coil, 20. Bushing component, 21. Semiconductor element, 30. Substrate, 32. Chip pad, 34. External lead, 40. Wire, 41. Stator core, 50. Resin layer, 51. Sealing material, 65. Resin seal, 71. Tooth front end, 72. Wall surface, 100. Rotor, 200. Power module, 101. Motor, 110. Rotor core, 112. Electromagnetic steel plate, 116. Slot section, 118a. End plate, 118b. End plate, 120. Magnet, 130. Fixing component, 140. Spacer section, 150. Hole section, 160. Riveting section, 170. Rotating shaft.

Claims

1. A disintegrating resin composition comprising a thermosetting resin, wherein the disintegrating resin composition is characterized in that: The following steps were used to determine that the seal strength ratio S2 / S1 was below 0.

30. step: The easily disintegrating resin composition was molded onto a copper substrate at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours to obtain a test piece. The test piece will be used to determine the shear strength [N / mm] of the copper substrate at room temperature and a speed of 300 μm / s. 2 Set as S1[N / mm] 2 ]; Furthermore, after heating the test piece at 300°C for 30 minutes, the adhesion strength [N / mm] with the copper substrate was measured at room temperature at a speed of 300 μm / s. 2 Set as S2[N / mm] 2 ].

2. The easily disintegrating resin composition according to claim 1, characterized in that: The adhesion strength S2 measured through the above steps is 3.0 N / mm. 2 the following.

3. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition was molded at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours. The resulting cured product had a linear expansion coefficient α2 of 46 ppm / °C or higher in the temperature range of 190°C to 230°C.

4. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition was molded at 175°C, 6.9 MPa, and 120 seconds, and then post-cured at 175°C for 4 hours. The resulting cured product had a linear expansion coefficient α3 of 60 ppm / °C or higher in the temperature range of 250–260°C.

5. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The thermosetting resin includes one or more selected from epoxy resin, phenoxy resin, polyimide resin, benzoxazine resin, unsaturated polyester resin, phenolic resin, melamine resin, silicone resin, cyanate ester resin, bismaleimide resin and acrylic resin.

6. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: It also contains a curing agent.

7. The easily disintegrating resin composition according to claim 6, characterized in that: The curing agent includes a phenolic curing agent.

8. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: It also contains a thermally expandable inorganic material, the content of which is 5 to 98% by mass relative to the total amount of the easily disintegrating resin composition.

9. The easily disintegrating resin composition according to claim 8, characterized in that: The thermally expandable inorganic material includes one or more selected from crystalline silicon dioxide, crystalline aluminum phosphate, and their derivatives.

10. The easily disintegrating resin composition according to claim 8, characterized in that: The thermally expandable inorganic material includes one or more of the following: quartz-type silica, white silica, tridymite-type silica, borosilicate-type aluminum phosphate, tridymite-type aluminum phosphate, crystallite-type aluminum phosphate, and clinonepheline.

11. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: It also contains aluminum hydroxide.

12. The easily disintegrating resin composition according to claim 11, characterized in that: The content of aluminum hydroxide is 1% by mass or more relative to the total amount of the easily disintegrating resin composition.

13. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: It contains one or more selected from thermally expandable inorganic materials, inorganic fillers, and aluminum hydroxide. The total content of the thermally expandable inorganic material, the inorganic filler material, and the aluminum hydroxide is 60% or more by mass relative to the total amount of the easily disintegrating resin composition.

14. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition is in powder, granule, or ingot form.

15. A structure, characterized in that: Cured products comprising the easily disintegrating resin composition of claim 1 or 2.

16. A method for dismantling a structure, which is the method for dismantling the structure as described in claim 15, characterized in that, include: The process of heating the structure to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

17. A recycling method for recycling materials constituting the structure of claim 15, characterized in that, include: The process of heating the structure to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the structure.

18. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition is used to form the stationary components in the rotor. The rotor includes: The rotor core is fixedly mounted on a rotating shaft and has a plurality of holes arranged along the periphery of the rotating shaft; A magnet, which is inserted into the hole; and The fixing component is disposed in the space between the hole and the magnet.

19. A rotor, characterized in that: The cured product of the easily disintegrating resin composition of claim 18 is used as the fixing component.

20. A method for disassembling a rotor, which is the method for disassembling a rotor as described in claim 19, characterized in that, include: The process of heating the rotor to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

21. A recycling method for recycling materials constituting the rotor of claim 19, characterized in that, include: The process of heating the rotor to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the rotor.

22. The recycling method according to claim 21, characterized in that: The material is selected from one or more of the magnet inserted into the hole and the electromagnet plate.

23. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition is used to form a sealing component in the stator. The stator has: a stator core having a plurality of teeth and a plurality of slots alternately formed in the circumferential direction; A coil, which is wound in and housed in the slot, and has a pair of coil ends protruding axially from the stator core to both sides; and a sealing member, which is arranged to cover the coil within the slot.

24. A stator, characterized in that: The cured product of the easily disintegrating resin composition of claim 23 is used as the sealing component.

25. A method for dismantling a stator, which is the method for dismantling a stator as described in claim 24, characterized in that, include: The process of heating the stator to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

26. A recycling method for recycling materials constituting the stator of claim 24, characterized in that, include: The process of heating the stator to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the stator.

27. The recycling method according to claim 26, characterized in that: The material is selected from one or more of coils and electromagnet steel plates.

28. The easily disintegrating resin composition according to claim 1 or 2, characterized in that: The easily disintegrating resin composition is used to form sealing components in the power module. The power module includes: a wiring board; a plurality of electronic components mounted on the wiring board; and a sealing component that seals the electronic components.

29. A power module, characterized in that: The cured product of the easily disintegrating resin composition of claim 28 is used as the sealing component.

30. A method for disassembling a power module, which is the method for disassembling a power module as described in claim 29, characterized in that, include: The process of heating the power module to above 200°C to disintegrate the cured product of the easily disintegrating resin composition.

31. A recycling method for recycling materials constituting the power module of claim 29, characterized in that, include: The process of heating the power module to above 200°C to disintegrate the cured product of the easily disintegrating resin composition; and The process of recovering the material from the power module.

32. The recycling method according to claim 31, characterized in that: The material is a metal lead frame.

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