Molded stator and electric motor

Abstract

A molded stator comprises: a stator having a stator core and a coil wound on the stator core; and a molding material covering the stator, wherein the molding material is a cured product of a thermosetting resin composition containing (A) a saturated polyester resin, (B) a thermosetting resin, (C) an olefinically unsaturated monomer, (D) a thermal polymerization initiator, (E) glass fiber, (F) an inorganic filler, and (G) a thickener, wherein the (G) thickener is one or more selected from styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS), and the thermosetting resin composition comprises (B) the thermosetting resin and the aforementioned (C) olefinically unsaturated monomer. When the total amount of monomers is set to 100 parts by mass, the content of thickener (G) is 0.8 to 9 parts by mass, and saturated polyester resin (A) is a condensation polymer of diol and saturated polyacid. The saturated polyacid contains aromatic saturated polyacid or its anhydride and aliphatic saturated polyacid. In saturated polyester resin (A), the molar ratio of the structure derived from aromatic saturated polyacid or its anhydride to the structure derived from aliphatic saturated polyacid is 20:80 to 80:20. Saturated polyester resin (A) contains: block (X) as a condensation polymer of diol and aromatic saturated polyacid or its anhydride and block (Y) as a condensation polymer of diol and aliphatic saturated polyacid. The weight average molecular weight of block (X) is 3000 to 5000.

Description

Technical Field

[0001] This disclosure relates to a molding die, an electric motor having the molding die, and a thermosetting resin composition. Background Technology

[0002] In the manufacture of electric motors, transformers, and other electrical appliances, there is an increasing demand for miniaturization, thinning, lightweighting, and high output. Furthermore, due to the environmental characteristics of these devices, low noise and low vibration are also required. To meet these requirements, a structure has been proposed that uses molded resin to cover an electromagnetic coil wound around a stator core (Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2023-091064 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] When molding a stator by covering it with molding resin, as the stator shape becomes more complex, the cured molding resin produces both thin-walled and thick-walled sections. Furthermore, with the pursuit of thinner and lighter designs, the amount of molding resin needs to be reduced to its limit. As a result, the cured molding resin may lack sufficient strength, leading to cracks in the molded product. Moreover, if the molding resin's filling capacity is insufficient, the resin cannot completely fill the mold, resulting in defects in the molded product.

[0008] This disclosure provides a molded stud covered with molding material that has a good appearance without defects or cracks.

[0009] Methods for solving problems

[0010] The contents of this disclosure include the following schemes. [1]

[0012] A molding die has:

[0013] Stator, the stator having a stator core and coils wound on the stator core; and

[0014] The molding material covering the aforementioned stator.

[0015] in,

[0016] The above molding material is a cured product of a thermosetting resin composition containing (A) saturated polyester resin, (B) thermosetting resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, (F) inorganic filler, and (G) thickener.

[0017] The thickener mentioned above (G) is selected from one or more of styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS).

[0018] In the above-mentioned thermosetting resin composition, when the total amount of the above-mentioned thermosetting resin (B) and the above-mentioned olefinic unsaturated monomer (C) is set to 100 parts by mass, the content of the above-mentioned thickener (G) is 0.8 to 9 parts by mass.

[0019] The aforementioned (A) saturated polyester resin is a condensation polymer of diol and saturated polybasic acid.

[0020] The aforementioned saturated polybasic acids include aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids.

[0021] In the above-mentioned (A) saturated polyester resin, the molar ratio (from the structure derived from the above-mentioned aromatic saturated polybasic acid or its anhydride to the structure derived from the above-mentioned aliphatic saturated polybasic acid is 20:80 to 80:20.

[0022] The aforementioned (A) saturated polyester resin comprises: a block (X) as a condensation polymer of a diol and an aromatic saturated polyacid or its anhydride, and a block (Y) as a condensation polymer of a diol and an aliphatic saturated polyacid, wherein the weight-average molecular weight of the block (X) is 3000 to 5000. [2]

[0024] The molding die as described in [1], wherein the weight-average molecular weight of the saturated polyester resin (A) is 9500 to 13500. [3]

[0026] The molded stent as described in [1] or [2], wherein the aromatic saturated polyacid constituting the block (X) is selected from one or more of isophthalic acid and terephthalic acid. [4]

[0028] The molded stator as described in any one of [1] to [3], wherein the aliphatic saturated polyacid constituting the block (Y) is selected from one or more of succinic acid, adipic acid and sebacic acid. [5]

[0030] The molding die as described in any one of [1] to [4], wherein the weight-average molecular weight of the thermosetting resin (B) is 10,000 to 50,000. [6]

[0032] The molding die as described in any one of [1] to [5], wherein the thermosetting resin of (B) contains an unsaturated polyester resin.

[0033] The aforementioned unsaturated polyester resin is a condensation polymer of glycol, unsaturated polybasic acid, and optionally saturated polybasic acid.

[0034] The aforementioned diols contain propylene glycol and neopentyl glycol. [7]

[0036] The molding die as described in any one of [1] to [6], wherein, in the above-mentioned thermosetting resin composition, when the total amount of the above-mentioned (B) thermosetting resin and the above-mentioned (C) olefinic unsaturated monomer is set to 100 parts by mass,

[0037] contain

[0038] 5-30 parts by weight of the above-mentioned (A) saturated polyester resin

[0039] The above (B) thermosetting resin, 5-80 parts by weight,

[0040] 20-95 parts by mass of the above (C) olefinic unsaturated monomer

[0041] The above-mentioned (D) thermal polymerization initiator, 0.5-20 parts by weight,

[0042] The above (E) glass fiber, 5 to 200 parts by weight, and

[0043] 50 to 1000 parts by weight of the above (F) inorganic filler material. [8]

[0045] An electric motor, comprising:

[0046] The molded stent as described in any one of [1] to [7];

[0047] A rotor having a rotating shaft extending along an axial direction, and a rotating body containing a magnetic component extending along the axial direction and fixed to the rotating shaft, wherein the rotor is located inside the stator; and

[0048] The bearings that rotatably support the aforementioned rotor. [9]

[0050] A thermosetting resin composition comprising:

[0051] (A) Saturated polyester resin,

[0052] (B) Thermosetting resins,

[0053] (C) Alkene unsaturated monomers,

[0054] (D) Thermal polymerization initiator,

[0055] (E) Glass fiber,

[0056] (F) Inorganic filler materials, and

[0057] (G) Thickener,

[0058] in,

[0059] The thickener mentioned above (G) is selected from one or more of styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS).

[0060] When the total amount of the above-mentioned thermosetting resin (B) and the above-mentioned olefinic unsaturated monomer (C) is set to 100 parts by mass, the content of the above-mentioned thickener (G) is 0.8 to 9 parts by mass.

[0061] The aforementioned (A) saturated polyester resin is a condensation polymer of diol and saturated polybasic acid.

[0062] The aforementioned saturated polybasic acids include aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids.

[0063] In the above-mentioned (A) saturated polyester resin, the molar ratio (from the structure derived from the above-mentioned aromatic saturated polybasic acid or its anhydride to the structure derived from the above-mentioned aliphatic saturated polybasic acid is 20:80 to 80:20.

[0064] The aforementioned (A) saturated polyester resin comprises: a block (X) as a condensation polymer of a diol and an aromatic saturated polyacid or its anhydride, and a block (Y) as a condensation polymer of a diol and an aliphatic saturated polyacid, wherein the weight-average molecular weight of the block (X) is 3000 to 5000.

[10]

[0066] The thermosetting resin composition as described in [9], wherein the weight-average molecular weight of the saturated polyester resin of (A) is 9,500 to 13,500.

[11]

[0068] The thermosetting resin composition as described in [9] or

[10] , wherein the total amount of the above-mentioned (B) thermosetting resin and the above-mentioned (C) olefinic unsaturated monomer is set to 100 parts by mass,

[0069] contain

[0070] 5-30 parts by weight of the above-mentioned (A) saturated polyester resin

[0071] The above (B) thermosetting resin, 5-80 parts by weight,

[0072] 20-95 parts by mass of the above (C) olefinic unsaturated monomer

[0073] The above-mentioned (D) thermal polymerization initiator, 0.5-20 parts by weight,

[0074] The above (E) glass fiber, 5 to 200 parts by weight, and

[0075] 50 to 1000 parts by weight of the above (F) inorganic filler material.

[12]

[0077] A molding material, which is a cured product of any one of the thermosetting resin compositions described in [9] to

[11] .

[0078] The effects of the invention

[0079] According to this disclosure, a molded stud covered with molding material can be provided, which has a good appearance without defects or cracks. Attached Figure Description

[0080] Figure 1 This is a schematic cross-sectional view of an exemplary electric motor. Detailed Implementation

[0081] The embodiments of the present invention will now be described in detail. However, the present invention is not limited to the embodiments shown below.

[0082] In this specification, regarding numerical ranges, when using "~", the values ​​at both ends are included within the numerical range as the upper and lower limits, respectively. When multiple upper or lower limits are specified, a numerical range can be formed by all combinations of the upper and lower limits. Similarly, when multiple numerical ranges are specified, another numerical range can be formed by individually selecting and combining the upper and lower limits from these ranges.

[0083] In this specification, "(meth)acrylic acid" refers to methacrylic acid or acrylic acid, "(meth)acrylate" refers to acrylate or methacrylate, and "(meth)acryloyloxy" refers to acryloyloxy or methacryloyloxy.

[0084] In this specification, "thermosetting resin" refers to a resin that cures by forming a cross-linked structure when heated, indicating its state before curing.

[0085] In this specification, "olefin unsaturated bond" refers to a double bond formed between carbon atoms other than the carbon atoms that form the aromatic ring, and "olefin unsaturated monomer" refers to a monomer that has olefin unsaturated bonds.

[0086] In this specification, "weight-average molecular weight" and "number-average molecular weight" are values ​​determined by gel permeation chromatography (GPC) under the following conditions at room temperature (23°C) and obtained using a standard polystyrene standard curve.

[0087] Device: Shodex (trademark) GPC-101 ( )

[0088] Column: Shodex LF-804 (trademark) )

[0089] Column temperature: 40℃

[0090] Sample: 0.2% by mass tetrahydrofuran solution of the sample

[0091] Flow rate: 1 mL / min

[0092] Eluent: Tetrahydrofuran

[0093] Detector: Shodex (trademark) RI-71S )

[0094] In this specification, "acid value" refers to the acid value measured according to JIS K6901:2021 5.3. That is, acid value refers to the number of mg of potassium hydroxide required to neutralize the acidic components contained in 1g of non-volatile components other than the solvent.

[0095] <Electric motor>

[0096] An electric motor is a device that generates electromagnetic force by energizing internal coils, and generates rotational force by utilizing the repulsive or attractive forces between the coils and permanent magnets or electromagnets disposed on or around the spindle. Typically, an electric motor comprises: a stator having a stator core and coils wound around the stator core; and a rotating body containing magnetic components. In electric motors, a stator covered by molding material is called a molded motor. In this specification, the stator covered by molding material is referred to as a molded stator.

[0097] One embodiment of the electric motor includes: a molded stator; a rotor having a rotating shaft extending in an axial direction, and a rotating body containing a magnetic component extending in the axial direction and fixed to the rotating shaft, the rotor being located inside the stator; and a bearing rotatably supporting the rotor.

[0098] In an electric motor, the molding material constituting the molded stator is a cured product of a thermosetting resin composition described later. For structures in the electric motor other than the molding material, known structures can be used.

[0099] An exemplary cross-sectional view of an electric motor is shown in the figure. Figure 1 .exist Figure 1 The details of the bracket and the insulating components attached to the coil are omitted. Figure 1In this motor 10, there is a stator 11, a rotor 15, and a bearing 19 that rotatably supports the rotor 15. The stator 11 has a stator core 12 made of multiple metal plates and coils 13 formed by winding wires wound on the stator core 12. The stator 11 is covered by a molding material 14. The rotor 15 is located inside the stator 11. The rotor 15 has a rotating shaft 17 extending along the axial direction and a rotating body 18 fixed to the rotating shaft 17, the rotating body 18 including a magnet 16.

[0100] <Modifier>

[0101] A molded stator is a stator covered by a molding material. One embodiment of a molded stator includes: a stator having a stator core and coils wound on the stator core; and molding material covering the stator. It should be noted that the stator does not need to be entirely covered by the molding material.

[0102] The molding material constituting the molded stator is a cured product of the thermosetting resin composition described later. For the structure of the molded stator other than the molding material, known structures can be used. There are no particular restrictions on the electric motor used in the molded stator; known electric motors can be used.

[0103] <Molding Materials>

[0104] The molding material is a cured product of the thermosetting resin composition described later. By using the molding material, a low-noise and low-vibration electric motor can be obtained.

[0105] <Thermosetting Resin Composition>

[0106] One embodiment of the thermosetting resin composition contains (A) a saturated polyester resin, (B) a thermosetting resin, (C) an olefinically unsaturated monomer, (D) a thermal polymerization initiator, (E) glass fiber, (F) an inorganic filler, and (G) a thickener having a specific structure. The thickener (G) is selected from one or more of styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS). When the total amount of (B) the thermosetting resin and (C) the olefinically unsaturated monomer is set to 100 parts by mass, the content of the thickener (G) is 0.8 to 9 parts by mass. (A) Saturated polyester resin is a condensation polymer of a diol and a saturated polyacid, wherein the saturated polyacid includes an aromatic saturated polyacid or its anhydride, and an aliphatic saturated polyacid. In (A) saturated polyester resin, the molar ratio (from aromatic saturated polyacid or its anhydride to aliphatic saturated polyacid) is 20:80 to 80:20. (A) saturated polyester resin comprises: a block (X) as a condensation polymer of a diol and an aromatic saturated polyacid or its anhydride, and a block (Y) as a condensation polymer of a diol and an aliphatic saturated polyacid. The weight-average molecular weight of block (X) is 3000 to 5000. The cured thermosetting resin composition is suitable as a molding material for covering stators. By using the cured thermosetting resin composition containing (A) saturated polyester resin with a specific structure as a molding material, a molded stator with a good appearance free of cracks can be obtained. Furthermore, a molded stator with excellent durability against thermal cycling can be obtained. By using a specific amount of (G) thickener, a thermosetting resin composition with excellent filling properties during molding can be obtained, thereby obtaining a molded stud without defects.

[0107] [(A) Saturated polyester resin]

[0108] (A) Saturated polyester resin is a condensation polymer of diol and saturated polyacid, the saturated polyacid containing aromatic saturated polyacid or its anhydride and aliphatic saturated polyacid. In (A) saturated polyester resin, the molar ratio of the structure derived from aromatic saturated polyacid or its anhydride to the structure derived from aliphatic saturated polyacid is 20:80 to 80:20. (A) saturated polyester resin contains: a block (X) as a condensation polymer of diol and aromatic saturated polyacid or its anhydride and a block (Y) as a condensation polymer of diol and aliphatic saturated polyacid. The weight average molecular weight of block (X) is 3000 to 5000.

[0109] (A) Saturated polyester resin can be used alone or in combination with two or more types. By using (A) saturated polyester resin, cracking during molding can be suppressed.

[0110] It should be noted that, in this disclosure, styrene monomers and the like contained in commercially available saturated polyester resins are classified as (C) olefinic unsaturated monomers.

[0111] There are no particular limitations on diols as long as they are compounds having two hydroxyl groups. Examples of diols include alkylene glycols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, neopentanediol, 2-methyl-1,3-propanediol, 1,4-cyclohexanediol, and hydrogenated bisphenol A; polyoxyalkylene polyols such as diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, and polyethylene glycol; bisphenol A; and ethylene oxide adducts of bisphenol A and propylene oxide adducts of bisphenol A, etc. From the viewpoint of crack resistance during molding, it is preferable to select one or more of alkylene glycols and polyoxyalkylene polyols, more preferably polyoxyalkylene glycols, and even more preferably one or more of diethylene glycol, dipropylene glycol, and triethylene glycol. In particular, from the viewpoint of improving the durability of the molded article, it is preferable to use polyoxyethylene glycol and polyoxypropylene glycol together, and more preferably to use diethylene glycol and dipropylene glycol together. The molar ratio of polyoxyethylene glycol to polyoxypropylene glycol or diethylene glycol to dipropylene glycol is not particularly limited. From the viewpoint of improving durability, a ratio of 40:60 to 80:20 is preferred, more preferably 50:50 to 70:30, further preferably 55:45 to 65:35, and particularly preferably 58:42 to 63:37. The glycols can be used alone or in combination with two or more.

[0112] Saturated polybasic acids include aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids. Examples of aromatic saturated polybasic acids or their anhydrides include phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, nitrophthalic acid, and halophthalic anhydride. Preferably, the aromatic saturated polybasic acid or its anhydride is selected from one or more of aromatic saturated dibasic acids and their anhydrides; more preferably, it is selected from one or more of phthalic acid, phthalic anhydride, isophthalic acid, and terephthalic acid; and even more preferably, it is selected from one or more of isophthalic acid and terephthalic acid. Aromatic saturated polybasic acids or their anhydrides can be used alone or in combination with two or more. Examples of aliphatic saturated polybasic acids include succinic acid, adipic acid, sebacic acid, oxalic acid, malonic acid, azelaic acid, and glutaric acid. As an aliphatic saturated polybasic acid, an aliphatic saturated dibasic acid is preferred, more preferably an aliphatic saturated dibasic acid with 4 to 10 carbon atoms, and even more preferably one or more selected from succinic acid, adipic acid, and sebacic acid. The aliphatic saturated polybasic acid can be used alone or in combination with two or more. From the viewpoint of crack resistance during molding, it is preferable to use one or more selected from isophthalic acid and terephthalic acid together with one or more selected from succinic acid, adipic acid, and sebacic acid.

[0113] The total ratio of aromatic saturated polybasic acid and its anhydride to the total ratio of aromatic saturated polybasic acid, its anhydride, and aliphatic saturated polybasic acid is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. The total ratio of aromatic saturated polybasic acid and its anhydride to the total ratio of aromatic saturated polybasic acid, its anhydride, and aliphatic saturated polybasic acid is preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. When the total ratio of aromatic saturated polybasic acid and its anhydride is within the above range, the moldability is better, and the properties of the cured product can be further improved.

[0114] The ratio of aliphatic saturated polybasic acid to aromatic saturated polybasic acid, the anhydride of aromatic saturated polybasic acid, and the total of aliphatic saturated polybasic acid is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. The ratio of aliphatic saturated polybasic acid to aromatic saturated polybasic acid, the anhydride of aromatic saturated polybasic acid, and the total of aliphatic saturated polybasic acid is preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. When the ratio of aliphatic saturated polybasic acid is within the above range, crack resistance can be improved.

[0115] In (A) saturated polyester resin, the molar ratio of structures derived from aromatic saturated polybasic acids or their anhydrides to structures derived from aliphatic saturated polybasic acids is 20:80 to 80:20, preferably 30:70 to 70:30, and more preferably 40:60 to 60:40.

[0116] From the viewpoint of crack resistance during molding, (A) saturated polyester resin comprises blocks (X) and blocks (Y), wherein the blocks (X) are condensation polymers of diols and aromatic saturated polyacids or their anhydrides, and the weight-average molecular weight of the blocks (X) is 3000 to 5000, and the blocks (Y) are condensation polymers of diols and aliphatic saturated polyacids.

[0117] In (A) saturated polyester resin, structures derived from aromatic saturated polybasic acids or their anhydrides may be dispersed in portions other than blocks (X) and (Y).

[0118] The weight-average molecular weight of block (X) is 3000 or more, preferably 3500 or more. The weight-average molecular weight of block (X) is 5000 or less, preferably 4500 or less. When the weight-average molecular weight of block (X) is within the above range, the crack resistance during molding is good.

[0119] The aromatic saturated polybasic acid or its anhydride constituting block (X) is preferably selected from one or more of aromatic saturated dibasic acids and their anhydrides, more preferably selected from one or more of phthalic acid, phthalic anhydride, isophthalic acid and terephthalic acid, and even more preferably selected from one or more of isophthalic acid and terephthalic acid.

[0120] The aliphatic saturated polycarboxylic acid constituting block (Y) is preferably an aliphatic saturated dicarboxylic acid, more preferably an aliphatic saturated dicarboxylic acid with 4 to 10 carbon atoms, and even more preferably one or more selected from succinic acid, adipic acid and sebacic acid.

[0121] Preferred combinations of glycols and saturated polycarboxylic acids include polyoxyalkylene glycols and saturated dicarboxylic acids. More specifically, examples include combinations of diethylene glycol and isophthalic acid; diethylene glycol and adipic acid; dipropylene glycol and isophthalic acid; dipropylene glycol and adipic acid; diethylene glycol, isophthalic acid, and adipic acid; dipropylene glycol, isophthalic acid, and adipic acid; and combinations of diethylene glycol, dipropylene glycol, isophthalic acid, and adipic acid. Among these, combinations of diethylene glycol, isophthalic acid, and adipic acid, dipropylene glycol, isophthalic acid, and adipic acid, and combinations of diethylene glycol, dipropylene glycol, isophthalic acid, and adipic acid exhibit good crack resistance during molding and are therefore preferred.

[0122] The weight-average molecular weight of (A) saturated polyester resin is preferably 9500 or more, more preferably 9800 or more, and even more preferably 10000 or more. The weight-average molecular weight of (A) saturated polyester resin is preferably 13500 or less, more preferably 13000 or less, and even more preferably 12500 or less. When the weight-average molecular weight is within the above range, crack formation during molding is further suppressed. Although not subject to any theoretical constraints, it can be considered that by setting the weight-average molecular weight of (A) saturated polyester resin to the above range, the compatibility with (B) thermosetting resin and the dispersibility of components (C) to (G) are improved, thereby suppressing crack formation during molding. The weight-average molecular weight of (A) saturated polyester resin can be adjusted by the reaction time during the synthesis of (A) saturated polyester resin. Specifically, the longer the reaction time, the larger the weight-average molecular weight; the shorter the reaction time, the smaller the weight-average molecular weight.

[0123] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (A) saturated polyester resin is preferably 5 parts by mass or more, more preferably 8 parts by mass or more, and even more preferably 10 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (A) saturated polyester resin is preferably 30 parts by mass or less, more preferably 25 parts by mass or less, and even more preferably 20 parts by mass or less. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (A) saturated polyester resin is preferably 5 to 30 parts by mass, more preferably 8 to 25 parts by mass, and even more preferably 10 to 20 parts by mass. When the content of (A) saturated polyester resin in the thermosetting resin composition is 5 parts by mass or more, the generation of cracks during molding can be further suppressed. When the content of (A) saturated polyester resin in the thermosetting resin composition is less than 30 parts by mass, the thermosetting resin composition has better moldability and the mechanical properties of the cured product.

[0124] (A) Synthesis method of saturated polyester resin)

[0125] (A) Saturated polyester resin can be synthesized using the above-mentioned raw materials by a known method. The various conditions for synthesizing (A) saturated polyester resin are appropriately set according to the raw materials used and their quantities.

[0126] Esterification reactions typically occur in a stream of inert gases such as nitrogen, at temperatures ranging from 140°C to 230°C, under pressure or reduced pressure. An esterification catalyst can be used as needed during the reaction. Examples of known esterification catalysts include manganese acetate, dibutyltin oxide, stannous oxalate, zinc acetate, and cobalt acetate. Esterification catalysts can be used alone or in combination of two or more.

[0127] The equivalent of the hydroxyl group of the diol relative to the total carboxyl group of the saturated polybasic acid is preferably set in the range of 0.9 to 1.2.

[0128] From the viewpoint of crack resistance during molding, (A) saturated polyester resin comprises: a block (X) as a condensation product of a diol and an aromatic saturated polybasic acid or its anhydride, and a block (Y) as a condensation product of a diol and an aliphatic saturated polybasic acid. Such (A) saturated polyester resin can be obtained by first adding one of the saturated polybasic acids to a reaction vessel to carry out an esterification reaction; after a certain amount of the saturated polybasic acid has been consumed, adding another saturated polybasic acid to the reaction vessel to carry out an esterification reaction until the desired weight-average molecular weight is obtained. For example, (A) saturated polyester resin can be synthesized as follows: first, an equimolar amount of a diol and an aromatic saturated polybasic acid or its anhydride, and an aromatic saturated polybasic acid or its anhydride, are added to a reaction vessel to carry out an esterification reaction; after a certain amount of the aromatic saturated polybasic acid or its anhydride has been consumed, an aliphatic saturated polybasic acid is added to the reaction vessel to carry out an esterification reaction.

[0129] The weight-average molecular weight of block (X) can be adjusted by the timing of the subsequent addition of the aliphatic saturated polybasic acid. For example, by tracking the acid value of the reaction solution, i.e., the residual amount of the aromatic saturated polybasic acid or its anhydride added first, the aliphatic saturated polybasic acid can be added when the desired residual amount is reached. From the viewpoint of crack resistance, the acid value of the reaction solution when adding the aliphatic saturated polybasic acid is preferably 30 KOH mg / g or less, more preferably 20 KOH mg / g or less, and even more preferably 10 KOH mg / g or less. The acid value of the reaction solution when adding the aliphatic saturated polybasic acid can be 1 KOH mg / g or more, 3 KOH mg / g or more, or 5 KOH mg / g or more.

[0130] [(B) Thermosetting resin]

[0131] (B) Thermosetting resins are not particularly limited to thermosetting resins that are commonly used as sealing materials. For example, resins having functional groups that can form cross-linked structures when heated and cured as thermosetting resin compositions are preferred. In particular, from the viewpoint that they can also react with (C) olefin unsaturated monomers, resins having multiple olefin unsaturated groups as functional groups are preferred.

[0132] (B) The weight-average molecular weight of the thermosetting resin is preferably 2,000 or more, more preferably 5,000 or more, and even more preferably 10,000 or more. (B) The weight-average molecular weight of the thermosetting resin is preferably 50,000 or less, more preferably 40,000 or less, and even more preferably 35,000 or less. When the weight-average molecular weight is within the above range, crack formation during molding is further suppressed. Although not bound by any theory, it can be considered that by setting the weight-average molecular weight of the (B) thermosetting resin to the above range, the compatibility with the (A) saturated polyester resin and the dispersibility of components (C) to (G) are improved, thereby suppressing crack formation during molding. It should be noted that the weight-average molecular weight of the (B) thermosetting resin refers to the weight-average molecular weight of the resin in its pre-cured state.

[0133] Specific examples of thermosetting resins (B) include (B-1) unsaturated polyester resins, (B-2) vinyl ester resins, (B-3) urethane (meth)acrylate resins, (B-4) diallyl phthalate resins, and (B-5) epoxy resins. From the viewpoints of moldability, flowability, and curing shrinkage, thermosetting resins (B) preferably contain (B-1) unsaturated polyester resins. Thermosetting resins (B) can be used alone or in combination of two or more types.

[0134] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (B) thermosetting resin is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 20 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (B) thermosetting resin is preferably 80 parts by mass or less, more preferably 60 parts by mass or less, and even more preferably 40 parts by mass or less. If the content of (B) thermosetting resin in the thermosetting resin composition is 5 parts by mass or more, the cured product has good mechanical strength. If the content of (B) thermosetting resin in the thermosetting resin composition is 80 parts by mass or less, the viscosity of the thermosetting resin composition can be adjusted to an appropriate range, resulting in good moldability.

[0135] <(B-1) Unsaturated polyester resin>

[0136] (B-1) The unsaturated polyester resin is a condensation polymer of a polyol and an unsaturated polyacid, or a condensation polymer of a polyol, an unsaturated polyacid, and a saturated polyacid, without particular limitation. (B-1) The unsaturated polyester resin is preferably a condensation polymer of a glycol, an unsaturated polyacid, and optionally a saturated polyacid, more preferably a condensation polymer of a glycol containing propylene glycol, an unsaturated polyacid, and optionally a saturated polyacid, and even more preferably a condensation polymer of a glycol containing propylene glycol and neopentyl glycol, an unsaturated polyacid, and optionally an aromatic saturated polyacid.

[0137] (B-1) unsaturated polyester resin can be used alone or in combination with two or more types. By using (B-1) unsaturated polyester resin, cured products with excellent mechanical strength and heat resistance can be obtained.

[0138] It should be noted that, in this disclosure, reactive diluents such as styrene monomers contained in commercially available unsaturated polyester resins are classified as (C) olefinic unsaturated monomers.

[0139] There are no particular limitations on polyols as long as they are compounds having two or more hydroxyl groups. Preferably, polyols are selected from one or more diols and triols, and more preferably diols. Examples of polyols include alkylene glycols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, neopentanediol, 2-methyl-1,3-propanediol, 1,4-cyclohexanediol, and hydrogenated bisphenol A; polyoxyalkylene polyols such as diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, and polyethylene glycol; bisphenol A; epoxyalkane-modified bisphenol A such as ethylene oxide adducts and propylene oxide adducts of bisphenol A; and glycerol. From the viewpoint of crack resistance during molding, alkylene glycols are preferred, more preferably alkylene glycols with 2 to 6 carbon atoms, and even more preferably one or more selected from ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, and neopentanediol, with propylene glycol being particularly preferred. From the viewpoint of improving the durability of molded articles, it is preferable to use propylene glycol and neopentyl glycol together. From the viewpoint of chemical resistance, it is preferable to use propylene glycol and hydrogenated bisphenol A together. Polyols can be used alone or in combination with two or more.

[0140] Unsaturated polybasic acids are not particularly limited to compounds having olefinic unsaturated bonds and two or more carboxyl groups, or their anhydrides; known unsaturated polybasic acids can be used. In particular, unsaturated polybasic acids with 4 to 6 carbon atoms, or their anhydrides, are less expensive and produce thermosetting resin compositions with superior mechanical strength and heat resistance in the cured product, and are therefore preferred. Unsaturated dibasic acids are preferred. Examples of unsaturated polybasic acids include maleic acid, maleic anhydride, fumaric acid, citracic acid, itaconic acid, and chloromaleic acid. More preferably, one or more of fumaric acid, maleic acid, maleic anhydride, and itaconic acid are selected. Unsaturated polybasic acids can be used alone or in combination of two or more.

[0141] A preferred combination of polyol and unsaturated polyacid is a diol and an unsaturated diacid, more preferably an alkylene glycol and an unsaturated diacid with 4 to 6 carbon atoms. More specifically, examples include combinations of maleic anhydride, propylene glycol, and neopentyl glycol; combinations of maleic anhydride and propylene glycol; combinations of fumaric acid and propylene glycol; combinations of maleic anhydride, propylene glycol, neopentyl glycol, and hydrogenated bisphenol A; and combinations of maleic anhydride, fumaric acid, propylene glycol, neopentyl glycol, and hydrogenated bisphenol A. Combinations of maleic anhydride, propylene glycol, and neopentyl glycol, and combinations of maleic anhydride and propylene glycol, offer lower costs and improved crack resistance during molding and durability of the molded product, and are therefore preferred.

[0142] There are no particular limitations on saturated polybasic acids; any compound or its anhydride that does not have an olefinic unsaturated bond and has two or more carboxyl groups can be used. Examples of saturated polybasic acids include, for instance, aromatic saturated polybasic acids or their anhydrides such as phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, nitrophthalic acid, and halophthalic anhydride; aliphatic saturated polybasic acids such as succinic acid, adipic acid, sebacic acid, oxalic acid, malonic acid, azelaic acid, and glutaric acid; and the anhydrides of cyclic aliphatic saturated polybasic acids such as hexahydrophthalic anhydride. Saturated polybasic acids can be used alone or in combination of two or more.

[0143] The weight-average molecular weight of the (B-1) unsaturated polyester resin is not particularly limited. The weight-average molecular weight of the (B-1) unsaturated polyester resin is preferably 2,000 to 50,000, more preferably 5,000 to 50,000, further preferably 10,000 to 50,000, and particularly preferably 13,000 to 35,000. When the weight-average molecular weight is 2,000 to 50,000, the moldability of the thermosetting resin composition is better. When the weight-average molecular weight is 2,000 to 50,000, the cracking during molding is further suppressed. Although not bound by any theory, it can be considered that by setting the weight-average molecular weight of the (B-1) unsaturated polyester resin to the above range, the compatibility with the (A) saturated polyester resin and the dispersibility of components (C) to (G) are improved, and the cracking during molding is suppressed.

[0144] The degree of unsaturation of the (B-1) unsaturated polyester resin is preferably 50 to 100 mol%, more preferably 60 to 100 mol%, and even more preferably 70 to 100 mol%. When the degree of unsaturation is within the above range, the thermosetting resin composition containing the (B-1) unsaturated polyester resin has better moldability.

[0145] (B-1) The degree of unsaturation of unsaturated polyester resin can be calculated using the following formula, which can be used to measure the number of moles of unsaturated polybasic acids and saturated polybasic acids used as raw materials.

[0146] Degree of unsaturation (mol%) = {(number of moles of unsaturated polyacid × number of olefinic unsaturated bonds per molecule of unsaturated polyacid) / (number of moles of unsaturated polyacid + number of moles of saturated polyacid)} × 100

[0147] (B-1) Synthesis method of unsaturated polyester resin)

[0148] (B-1) Unsaturated polyester resin can be synthesized using the above-mentioned raw materials by a known method. The various conditions for synthesizing (B-1) unsaturated polyester resin are appropriately set according to the raw materials used and their quantities.

[0149] Esterification reactions typically occur in a stream of inert gases such as nitrogen, at temperatures ranging from 140°C to 230°C, under pressure or reduced pressure. An esterification catalyst can be used as needed during the reaction. Examples of known esterification catalysts include manganese acetate, dibutyltin oxide, stannous oxalate, zinc acetate, and cobalt acetate. Esterification catalysts can be used alone or in combination of two or more.

[0150] In order to increase the molecular weight by improving the reaction rate, the equivalent of the hydroxyl groups of the polyol relative to the total amount of carboxyl groups of the unsaturated polyacid and optionally the saturated polyacid is preferably set in the range of 0.9 to 1.2.

[0151] (B) The content of (B-1) unsaturated polyester resin in the thermosetting resin is preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. If the content of (B-1) unsaturated polyester resin is 75% by mass or more, appropriate moldability, flowability, and curing shrinkage can be ensured. There is no particular upper limit to the content of (B-1) unsaturated polyester resin in the thermosetting resin. For example, it can be 100% by mass, 97% by mass, or 95% by mass.

[0152] <(B-2) Vinyl Ester Resin>

[0153] (B-2) Vinyl ester resins are generally compounds with olefinic unsaturated bonds obtained by (a) the ring-opening reaction of the epoxy group in an epoxy compound having two or more epoxy groups with the carboxyl group in an unsaturated monocarboxylic acid having an olefinic unsaturated bond and a carboxyl group. Information on (B-2) vinyl ester resins is available, for example, in the Polyester Resin Handbook (Nikkan Kogyo Shimbun, 1988).

[0154] (B-2) vinyl ester resins can be used alone or in combination with two or more. From an operational perspective, (B-2) vinyl ester resins are typically used after dilution with (C) olefinic unsaturated monomers. By using (B-2) vinyl ester resins, the material cost of thermosetting resin compositions can be reduced.

[0155] (B-2) The weight-average molecular weight (Mw) of the vinyl ester resin can be adjusted according to the desired physical properties, but from an operability point of view, it is preferably in the range of 500 to 5,000.

[0156] (a) Epoxy compounds

[0157] (a) There are no particular limitations on the epoxy compound as long as it has two or more epoxy groups. Preferably, it is selected from one or more bisphenol type epoxy compounds and phenolic varnish type epoxy compounds, more preferably bisphenol type epoxy compounds. By using (a) epoxy compound as a raw material in (B-2) vinyl ester resin, the mechanical strength and corrosion resistance of the cured product are further improved.

[0158] Examples of bisphenol-type epoxy compounds include compounds obtained by reacting bisphenol compounds such as bisphenol A, bisphenol F, bisphenol S, and tetrabromobisphenol A with epichlorohydrin and / or methylepimerol; compounds obtained by glycidyl etherification of any one or more of the above bisphenol compounds, and condensates of any one or more of the above bisphenol compounds, followed by reaction with epichlorohydrin and / or methylepimerol. From a durability viewpoint, the reactant of a bisphenol compound with epichlorohydrin is preferred, and the reactant of bisphenol A with epichlorohydrin is more preferred.

[0159] Examples of phenolic varnish-type epoxy compounds include compounds obtained by reacting phenolic varnish or cresol varnish with epichlorohydrin and / or methyl epichlorohydrin.

[0160] (b) Unsaturated monocarboxylic acids)

[0161] (b) There are no particular restrictions on the unsaturated monocarboxylic acid as long as it is a monocarboxylic acid with an olefinic unsaturated bond. Preferred are methacrylic acid, acrylic acid, crotonic acid, cinnamic acid, etc., more preferably acrylic acid or methacrylic acid, and from the viewpoint of corrosion resistance of the cured product, methacrylic acid is even more preferred.

[0162] (B-2) Synthesis method of vinyl ester resin)

[0163] (B-2) Vinyl ester resins can be synthesized by known synthetic methods. For example, one method is to react in a heated and stirred reaction vessel, in the presence of an esterification catalyst and (a) an epoxy compound, with the addition of (b) an unsaturated monocarboxylic acid, at 70–150°C, preferably 80–140°C, and more preferably 90–130°C.

[0164] As esterification catalysts, known catalysts such as triethylamine, N,N-dimethylbenzylamine, N,N-dimethylaniline, tertiary amines such as diazabicyclooctane, triphenylphosphine, and diethylamine hydrochloride can be used.

[0165] Regarding the mixing ratio of (a) the epoxy compound and (b) the unsaturated monocarboxylic acid, it is preferable to mix them in such a way that the total amount of epoxy groups in (a) the epoxy compound is 1 mole and the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 0.3 to 1.2 moles, more preferably 0.4 to 1.1 moles, and even more preferably 0.5 to 1.0 moles. If the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 0.3 moles or more, a cured product with sufficient hardness can be obtained when the thermosetting resin composition is cured. On the other hand, if the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 1.2 moles or less, unreacted (b) unsaturated monocarboxylic acid can be reduced when synthesizing (B-2) vinyl ester resin, and therefore a cured product with excellent mechanical strength can be obtained.

[0166] When the thermosetting resin composition is heated to cure, unreacted (b)unsaturated monocarboxylic acid sometimes volatilizes, so it is preferable to minimize the content of unreacted (b)unsaturated monocarboxylic acid. For example, the content of unreacted (b)unsaturated monocarboxylic acid is preferably 5% by mass or less, more preferably 3% by mass or less, relative to the total amount of (B-2) vinyl ester resin and unreacted (b)unsaturated monocarboxylic acid.

[0167] (B) The content of (B-2) vinyl ester resin in thermosetting resins can be 1% by mass or more, 3% by mass or more, or 5% by mass or more. There is no particular upper limit to the content of (B-2) vinyl ester resin in thermosetting resins. For example, it can be 25% by mass, 20% by mass, or 10% by mass.

[0168] <(B-3) Carbamate (meth)acrylate resin>

[0169] Examples of (B-3) urethane (meth)acrylate resins include, for instance, resins obtained by introducing (meth)acryloyl groups into the two ends of a polyurethane obtained by reacting a polyisocyanate with a polyol.

[0170] As a polyol, the compound described as a raw material for the above-mentioned (B-1) unsaturated polyester resin can be used without particular restriction.

[0171] Examples of polyisocyanates include, for instance, aliphatic polyisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate, and trimethylhexane diisocyanate; cyclic aliphatic polyisocyanates such as hydrogenated phenylenediamine diisocyanate, isophorone diisocyanate, methylcyclohexane-2,4 (or 2,6)-diisocyanate, 4,4'-methylenebis(cyclohexyl)isocyanate, and 1,3-(isocyanatomethyl)cyclohexane; aromatic polyisocyanates such as toluene diisocyanate, phenylenediamine diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and triphenylmethane triisocyanate; and adducts, isocyanurates, and biuretates of these polyisocyanates. Polyisocyanates can be used alone or in combination of two or more.

[0172] When introducing a (meth)acryloyl group, one can use, for example, a method of reacting a hydroxyl-containing (meth)acrylic compound with a terminal isocyanate group, or a method of reacting an isocyanate-containing (meth)acrylic compound such as 2-(meth)acryloyloxyethyl isocyanate, 2-(meth)acryloyloxypropyl isocyanate, or 1,1-bis(acryloyloxymethyl)ethyl isocyanate with a terminal hydroxyl group. Examples of hydroxyl-containing (meth)acrylate compounds include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, caprolactone-modified hydroxyalkyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, tri(hydroxyethyl)isocyanurate di(meth)acrylate, pentaerythritol tri(meth)acrylate, glycerol mono(meth)acrylate, and hydroxyethylacrylamide, preferably 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, caprolactone-modified hydroxyalkyl (meth)acrylate, and hydroxyethylacrylamide. Isocyanate-containing (meth)acrylate compounds and hydroxyl-containing (meth)acrylate compounds can be used individually or in combination of two or more.

[0173] (B) The content of (B-3) urethane (meth)acrylate resin in the thermosetting resin can be 1% by mass or more, 3% by mass or more, or 5% by mass or more. (B) There is no particular upper limit to the content of (B-3) urethane (meth)acrylate resin in the thermosetting resin. For example, it can be 25% by mass, 20% by mass, or 10% by mass.

[0174] <(B-4) diallyl phthalate resin>

[0175] (B-4) Diallyl phthalate resin is an oligomer of diallyl phthalate, and conventionally known diallyl phthalate resins can be used without particular restrictions. (B-4) Diallyl phthalate resin can be used alone or in combination with two or more types.

[0176] (B) The content of (B-4) diallyl phthalate resin in thermosetting resins can be 1% by mass or more, 3% by mass or more, or 5% by mass or more. (B) There is no particular upper limit to the content of (B-4) diallyl phthalate resin in thermosetting resins. For example, it can be 25% by mass, 20% by mass, or 10% by mass.

[0177] <(B-5) Epoxy Resin>

[0178] As (B-5) epoxy resin, compounds described in (a) Epoxy Compounds of (B-2) Vinyl Ester Resin may be used. (B-5) Epoxy Resin may be used alone or in combination with two or more.

[0179] (B) The content of (B-5) epoxy resin in thermosetting resins can be 1% by mass or more, 3% by mass or more, or 5% by mass or more. (B) There is no particular upper limit to the content of (B-5) epoxy resin in thermosetting resins. For example, it can be 25% by mass, 20% by mass, or 10% by mass.

[0180] [(C) olefinic unsaturated monomers]

[0181] (C) There are no particular restrictions on olefinic unsaturated monomers as long as they contain olefinic unsaturated bonds. (C) Olefinic unsaturated monomers can be used alone or in combination of two or more.

[0182] Specifically, examples include vinyl compounds such as styrene, vinyltoluene, tert-butylstyrene, methoxystyrene, divinylbenzene, and vinylnaphthalene; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, isodecanyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, furfuryl methacrylate, tetrahydrofurfuryl methacrylate, and benzene methacrylate. Esters, benzyl methacrylate, phenoxyethyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, allyl methacrylate, isobornyl methacrylate, acetyl acetyl methacrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, tricyclodecyl di(meth)acrylate, trimethylolpropane tri(meth)acrylate, and other (meth)acrylates; cyclounsaturated compounds such as acenaphthene and norbornene. From the viewpoint of copolymerization with (B) thermosetting resin, vinyl compounds are preferred, more preferably selected from one or more of styrene, vinyltoluene, tert-butylstyrene, and methoxystyrene, and even more preferably styrene.

[0183] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (C) olefinically unsaturated monomer is preferably 20 parts by mass or more, more preferably 40 parts by mass or more, and even more preferably 60 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (C) olefinically unsaturated monomer is preferably 95 parts by mass or less, more preferably 90 parts by mass or less, and even more preferably 80 parts by mass or less. When the content of (C) olefinically unsaturated monomer in the thermosetting resin composition is 20 parts by mass or more, the viscosity of the thermosetting resin composition can be adjusted to an appropriate range, resulting in good moldability. When the content of (C) olefinically unsaturated monomer in the thermosetting resin composition is 95 parts by mass or less, the cured product has good mechanical strength.

[0184] (D) Thermal polymerization initiator

[0185] (D) There are no particular limitations on thermal polymerization initiators as long as they generate free radicals through heating. Examples include acyl peroxides, peroxide esters, hydroperoxides, dialkyl peroxides, ketone peroxides, peroxy ketals, alkyl peresters, percarbonates, and other organic peroxides.

[0186] As (D) thermal polymerization initiators, among these organic peroxides, 1,1-di-tert-hexylcyclohexane peroxide, tert-hexyl isopropyl peroxide carbonate, tert-butyl octanoate peroxide, tert-butyl peroxide-2-ethylhexanoate, tert-hexyl peroxide-2-ethylhexanoate, tert-pentyl peroxide-2-ethylhexanoate, benzoyl peroxide, 1,1-di-tert-butyl peroxide-3,3,5-trimethylcyclohexane, tert-butyl isopropyl peroxide carbonate, tert-butyl peroxide benzoate, dicumyl peroxide, and di-tert-butyl peroxide are preferred. (D) Thermal polymerization initiators can be used alone or in combination of two or more.

[0187] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (D) thermal polymerization initiator is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 3 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (D) thermal polymerization initiator is preferably 20 parts by mass or less, more preferably 15 parts by mass or less, and even more preferably 10 parts by mass or less. If the content of (D) thermal polymerization initiator in the thermosetting resin composition is 0.5 parts by mass or more, the curing reaction during molding of the thermosetting resin composition proceeds uniformly, and the physical properties and appearance of the cured product are better. If the content of (D) thermal polymerization initiator in the thermosetting resin composition is 20 parts by mass or less, the thermosetting resin composition has good storage stability and improved operability.

[0188] [(E) Glass fiber]

[0189] (E) There are no particular restrictions on glass fibers as long as they are fibrous materials with an aspect ratio of 3 or higher. Examples include chopped glass fibers.

[0190] (E) The fiber length of the glass fiber is preferably 20 mm or less, more preferably 10 mm or less, and even more preferably 5 mm or less. When the fiber length is 20 mm or less, the thermosetting resin composition has good formability and the cured product has a good appearance. The fiber length is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 1 mm or more. When the fiber length is 0.1 mm or more, the cured product has good strength. (E) The average fiber diameter of the glass fiber is preferably 3 to 100 μm, more preferably 5 to 30 μm.

[0191] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (E) glass fiber is preferably 5 parts by mass or more, more preferably 20 parts by mass or more, and even more preferably 40 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (E) glass fiber is preferably 200 parts by mass or less, more preferably 150 parts by mass or less, and even more preferably 100 parts by mass or less. When the content of (E) glass fiber in the thermosetting resin composition is 5 parts by mass or more, the mechanical properties of the cured product obtained from the thermosetting resin composition are better. When the content of (E) glass fiber in the thermosetting resin composition is 200 parts by mass or less, the (E) glass fiber is more uniformly dispersed in the thermosetting resin composition, enabling the production of a homogeneous cured product.

[0192] [(F) Inorganic filler materials]

[0193] As the (F) inorganic filler material, particulate substances known in the art of this invention, other than magnesium hydroxide and magnesium oxide, can be used. By using the (F) inorganic filler material, the molding shrinkage of the molded article can be reduced, the viscosity of the thermosetting resin composition can be adjusted to improve workability, or the strength of the molded article can be increased.

[0194] Examples of inorganic fillers (F) include calcium carbonate, silicon dioxide, aluminum oxide, aluminum hydroxide, barium sulfate, calcium sulfate, calcium oxide, calcium hydroxide, wollastonite, clay, kaolin, mica, gypsum, anhydrous silicate, and glass powder. Calcium carbonate, aluminum oxide, and aluminum hydroxide are preferred due to their low cost. Inorganic fillers (F) can be used alone or in combination of two or more.

[0195] (F) The average particle size of the inorganic filler is preferably 1 to 100 μm, more preferably 1 to 60 μm, and even more preferably 1 to 50 μm. (F) When the average particle size of the inorganic filler is 1 μm or more, particle aggregation can be suppressed. On the other hand, when the average particle size of the inorganic filler is 100 μm or less, the thermosetting resin composition exhibits good moldability.

[0196] It should be noted that, in this specification, "average particle size" refers to the particle size distribution measured by a laser diffraction / scattering particle size distribution measuring device (…). The 50% particle size (D50) in the volume-based cumulative particle size distribution determined by FRA Corporation.

[0197] (F) There are no particular restrictions on the shape of inorganic filler materials. Examples include approximately spherical, ellipsoidal, scaly, and amorphous shapes.

[0198] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (F) inorganic filler is preferably 50 parts by mass or more, more preferably 100 parts by mass or more, and even more preferably 200 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (F) inorganic filler is preferably 1000 parts by mass or less, more preferably 800 parts by mass or less, and even more preferably 600 parts by mass or less. When the content of (F) inorganic filler in the thermosetting resin composition is 50 parts by mass or more, the mechanical properties of the cured product are better. When the content of (F) inorganic filler in the thermosetting resin composition is 1000 parts by mass or less, the (F) inorganic filler is more uniformly dispersed in the thermosetting resin composition, enabling the production of a homogeneous cured product.

[0199] (G) Thickener

[0200] As the (G) thickener, one or more selected from styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS) are used. By using a specific amount of the above-mentioned (G) thickener, a thermosetting resin composition with excellent filling properties during molding can be obtained, thereby obtaining a molded stud without defects. By using a specific amount of the above-mentioned (G) thickener, the flowability of the thermosetting resin composition during molding can be adjusted to a desired range, thereby obtaining a molded stud covered with molding material with a good appearance without cracks. It should be noted that the flowability of the thermosetting resin composition during molding can also be adjusted to a desired range by using magnesium oxide or magnesium hydroxide. However, since the flowability changes over time, there is a problem that it is difficult to ensure a certain usable time after preparing the thermosetting resin composition. As a result, there is a tendency for the following undesirable situations to occur: the filling properties during molding cannot be controlled, and a molded stud covered with molding material with a good appearance cannot be obtained. Furthermore, the shrinkage rate of the cured material tends to increase when magnesium oxide and magnesium hydroxide are used, which may lead to the following adverse conditions: it may be impossible to obtain molded studs with a good appearance without cracks covered by the molding material.

[0201] (G) There are no particular restrictions on the shape of the thickener. Examples include crumbs, powders, etc.

[0202] In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (G) thickener is 0.8 parts by mass or more, preferably 1.5 parts by mass or more, and more preferably 3 parts by mass or more. In the thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (G) thickener is 9 parts by mass or less, preferably 8 parts by mass or less, and more preferably 7 parts by mass or less. When the content of (G) thickener in the thermosetting resin composition is within the above range, the fluidity of the thermosetting resin composition can be adjusted to the desired range, thus resulting in good filling properties during molding. Furthermore, molded studs covered with molding material and having a good appearance without cracks can be obtained.

[0203] [(H) Other low-shrinkage agents]

[0204] The thermosetting resin composition may contain (H) other low-shrinkage agents besides saturated polyester resin, as needed. There are no particular limitations on the (H) other low-shrinkage agents; low-shrinkage agents known in the art can be used. Thermoplastic resins are preferred as (H) other low-shrinkage agents. Examples of (H) other low-shrinkage agents include, for example, polystyrene, polyethylene, polymethyl methacrylate, polyvinyl acetate, polycaprolactone, etc. Among these, polystyrene is preferred from the viewpoint of reducing the shrinkage rate of the cured product. The (H) other low-shrinkage agents may be used alone or in combination of two or more.

[0205] In a thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (H) other low-shrinkage agent can be 1 part by mass or more, 3 parts by mass or more, or 5 parts by mass or more. In a thermosetting resin composition, when the total amount of (B) thermosetting resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (H) other low-shrinkage agent can be 40 parts by mass or less, 30 parts by mass or less, or 20 parts by mass or less. When the content of (H) other low-shrinkage agent in the thermosetting resin composition is 1 part by mass or more, the shrinkage rate of the cured product decreases, and the desired dimensional accuracy can be obtained in the molded product. When the content of (H) other low-shrinkage agent in the thermosetting resin composition is 40 parts by mass or less, the moldability of the thermosetting resin composition and the mechanical properties of the cured product are better.

[0206] (I) Release agent

[0207] The thermosetting resin composition may contain (I) a release agent as needed. There are no particular limitations on the release agent (I), and release agents known in the art of this invention may be used. Examples of release agents (I) include, for instance, stearic acid, oleic acid, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, stearamide, oleamide, silicone oil, synthetic wax, etc. The release agent (I) may be used alone or in combination of two or more.

[0208] The content of (I) release agent when using it is preferably 1 to 40 parts by weight, more preferably 5 to 30 parts by weight, and even more preferably 8 to 20 parts by weight, relative to 100 parts by weight of (B) thermosetting resin. When the content of (I) release agent is 1 part by weight or more, the cured product has good demolding properties during mold forming, and the product has good manufacturability. On the other hand, when the content of (I) release agent is 40 parts by weight or less, there will be no excessive release agent contaminating the surface of the cured product, and a cured product with a good appearance can be obtained.

[0209] [Other Additives]

[0210] In addition to the above-mentioned components, the thermosetting resin composition may also contain thickeners, colorants, polymerization inhibitors, molding aids, and other components known in the technical field of this invention, within a range that does not impair the effects of this invention.

[0211] Colorants are used to color cured materials. Examples of colorants include various dyes, inorganic pigments, and organic pigments. Colorants can be used alone or in combination of two or more. The content of the colorant can be adjusted appropriately according to the desired degree of coloring of the cured material.

[0212] Examples of polymerization inhibitors include hydroquinone, trimethylhydroquinone, p-benzoquinone, naphthoquinone, tert-butylhydroquinone, catechol, p-tert-butylcatechol, and 2,6-di-tert-butyl-4-methylphenol. Inhibitors can be used alone or in combination of two or more. The content of the inhibitor can be adjusted appropriately according to the storage environment, storage period, and curing conditions of the thermosetting resin composition.

[0213] <Method for manufacturing thermosetting resin compositions>

[0214] Thermosetting resin compositions can be manufactured by mixing (A) saturated polyester resin, (B) thermosetting resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, (F) inorganic filler, (G) thickener, and (H) other low-shrinkage agents, (I) mold release agents and other additives as optional components as needed.

[0215] Examples of mixing methods include kneading. There are no particular limitations on the kneading method; for example, a kneader, a disperser, or a planetary mixer can be used. The kneading temperature is preferably 5°C to 50°C, more preferably 10°C to 40°C.

[0216] There are no particular restrictions on the mixing order of the components when manufacturing a thermosetting resin composition. For example, it is preferable to mix the thermosetting resin (B) with a portion or all of the olefinic unsaturated monomer (C) before mixing the other components, as this readily yields a thermosetting resin composition in which the components are well dispersed or uniformly mixed. At least a portion of the olefinic unsaturated monomer (C) may be pre-mixed with the thermosetting resin (B) to function as a solvent, dispersion medium, etc. At least a portion of the olefinic unsaturated monomer (C) may also be pre-mixed with the thickener (G) to function as a solvent, dispersion medium, etc.

[0217] <Methods for Manufacturing Molding Materials>

[0218] Molding materials can be manufactured by heating and curing a thermosetting resin composition. The conditions for curing the thermosetting resin composition can be appropriately set according to the materials used and the decomposition temperature of the (D) thermal polymerization initiator. As an example of preferred conditions, the temperature is 120 to 180°C, more preferably 120 to 160°C, and the curing time is 1 to 30 minutes.

[0219] <Method for manufacturing mold studs>

[0220] The stator can be manufactured, for example, by injecting a thermosetting resin composition into a mold in which the stator is positioned and then heating it. As for the molding method, there is no particular limitation; methods commonly practiced in the technical field of this invention, such as transfer molding and injection molding, can be cited.

[0221] More specifically, methods for manufacturing molded stators include, for example, opening the mold, pouring a thermosetting resin composition into the mold containing the stator, and curing it; and injecting the thermosetting resin composition from the outside into a closed mold containing the stator through a gate or other opening in the mold under reduced pressure inside the mold, or under pressure applied from the outside of the mold, such as in injection molding, and curing it. The conditions for curing the thermosetting resin composition in the mold can be appropriately set depending on the material used. An example of preferred conditions is a temperature of 120–180°C, more preferably 120°C–160°C, and a curing time of 1–30 minutes.

[0222] Example

[0223] The present invention will be described in more detail below through embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0224] The following are examples of the synthesis of (A) saturated polyester resin used in the Examples and (cA) saturated polyester resin used in the Comparative Examples.

[0225] The following substances were used as raw materials.

[0226] Diol:

[0227] diethylene glycol ( )

[0228] Dipropylene glycol ( )

[0229] Saturated polyacids:

[0230] isophthalic acid ( )

[0231] adipic acid ( )

[0232] [Synthesis example 1]

[0233] In a four-necked flask equipped with a thermometer, stirrer, inert gas inlet, and reflux cooler, 50 moles of isophthalic acid, 60 moles of diethylene glycol, and 40 moles of dipropylene glycol were added. The mixture was heated and stirred under a nitrogen atmosphere until the temperature reached 210°C for esterification. When the acid value of the reaction solution fell below 10 mg / g, 50 moles of adipic acid were added to continue the esterification reaction, yielding a saturated polyester resin. Subsequently, when the acid value of the reaction solution fell below 10 mg / g, styrene monomer was added in such a way that the total mass percentage of styrene monomer relative to the saturated polyester resin and styrene monomer was 40%, resulting in a mixture of styrene monomer and styrene. The weight-average molecular weight (Mw) of the obtained saturated polyester resin was 10,000. The weight-average molecular weight (Mw) of the block (X) of the obtained saturated polyester resin was 4,000.

[0234] [Table 1]

[0235]

[0236] [Synthesis Examples 2 to 5]

[0237] Except for the composition used in Table 1, the same procedure as in Synthesis Example 1 was followed to obtain a mixture of saturated polyester resin and styrene. The weight-average molecular weight (Mw) of the saturated polyester resin and the weight-average molecular weight (Mw) of the blocks (X) of the saturated polyester resin are listed in Table 1.

[0238] [Comparative Synthesis Example 1]

[0239] Except for reacting with the initial one-time input of the components listed in Table 1, the process was the same as in Synthesis Example 1 to obtain a mixture of saturated polyester resin and styrene. The weight-average molecular weight (Mw) of the saturated polyester resin is shown in Table 1.

[0240] (B) Examples of the synthesis of thermosetting resins are shown below.

[0241] The following substances were used as raw materials.

[0242] Diol:

[0243] Propylene glycol ( )

[0244] Neopentyl glycol ( )

[0245] Hydrogenated bisphenol A ( )

[0246] Unsaturated polyacids:

[0247] Maleic anhydride ( )

[0248] fumaric acid ( )

[0249] Saturated polyacids:

[0250] isophthalic acid ( )

[0251] [Synthesis Example 6] (B) Synthesis of thermosetting resins

[0252] In a four-necked flask equipped with a thermometer, stirrer, inert gas inlet, and reflux cooler, 100 moles of maleic anhydride, 60 moles of propylene glycol, and 40 moles of neopentyl glycol were added. Esterification was carried out under nitrogen atmosphere with stirring, and the temperature was raised to 210°C to obtain an unsaturated polyester resin. Then, styrene monomer was added so that the total mass of styrene monomer relative to the unsaturated polyester resin and styrene monomer was 40% by mass, resulting in a mixture of unsaturated polyester resin and styrene. The resulting unsaturated polyester resin had an unsaturation degree of 100 mol% and a weight-average molecular weight (Mw) of 20,000.

[0253] [Table 2]

[0254]

[0255] [Synthesis Examples 7 to 10]

[0256] Except for using the composition in Table 2, the same procedure as in Synthesis Example 6 was followed to obtain a mixture of unsaturated polyester resin and styrene. The weight-average molecular weight (Mw) of the unsaturated polyester resin is listed in Table 2.

[0257] The following substances were used as other ingredients.

[0258] (C) Unsaturated olefin monomers:

[0259] Styrene (Idemitsu Kosan Co., Ltd.)

[0260] (D) Thermal polymerization initiator:

[0261] · I (Tertiylhexyl peroxide isopropyl carbonate, Nippon Oil Co., Ltd.)

[0262] (E) Glass fiber:

[0263] • Chopped strand ECS-03B173 / P9 (glass chopped strands, fiber diameter 13μm, fiber length 3.0mm, Nippon Electric Glass Co., Ltd.)

[0264] (F) Inorganic filler materials:

[0265] • Aluminum hydroxide (average particle size 7μm, Nippon Light Metals Co., Ltd.)

[0266] (G) Thickener:

[0267] Styrene-butadiene rubber (Asahi Kasei Corporation)

[0268] Magnesium oxide (Kanto Chemical Co., Ltd.)

[0269] (H) Other low-shrinkage agents:

[0270] • Polystyrene (PS MS-200, Sekisui Chemicals Co., Ltd.)

[0271] <Example 1>

[0272] (Preparation of thermosetting resin compositions)

[0273] The following were added to a double-arm kneader: 28 parts by mass of a mixture of saturated polyester resin and styrene obtained from Synthesis Example 1, which served as (A) saturated polyester resin and (C) olefinic unsaturated monomer (17 parts by mass of saturated polyester resin and 11 parts by mass of styrene); 53 parts by mass of a mixture of unsaturated polyester resin and styrene obtained from Synthesis Example 6, which served as (B) thermosetting resin and (C) olefinic unsaturated monomer (32 parts by mass of unsaturated polyester resin and 21 parts by mass of styrene); 36 parts by mass of styrene, which served as (C) olefinic unsaturated monomer; and (D) a thermal polymerization initiator. A thermosetting resin composition was prepared by mixing 9 parts by weight of I; 85 parts by weight of chopped glass fiber ECS-03B173 / P9 as (E); 414 parts by weight of aluminum hydroxide as (F) inorganic filler; 6 parts by weight of styrene-butadiene rubber as (G) thickener; and 16 parts by weight of polystyrene as (H) other low-shrinkage agent, at 30°C for 30 minutes.

[0274] (Initial liquidity)

[0275] The flowability of the thermosetting resin composition was evaluated using the flow length, or helical flow value, measured by a helical flow test. Specifically, a trapezoidal helical flow mold (6.5 mm at the top, 8 mm at the bottom, and 2 mm at the top) was installed on a 50t transfer molding machine. Under the conditions of a feed rate of 50 g, a molding temperature of 140°C, and a molding pressure of 5 MPa, the helical flow value (cm) of the thermosetting resin composition was measured. The results are shown in Table 3.

[0276] (Changes in liquidity over time)

[0277] Thermosetting resin compositions, after being mixed and stored at 20°C for 30 days, were used to evaluate flowability by measuring the flow length, i.e., the helical flow value, through a helical flow test. Specifically, a trapezoidal helical flow mold (upper base 6.5 mm, lower base 8 mm, height 2 mm) was installed on a 50t transfer molding machine. Under conditions of 50 g feed rate, molding temperature 140°C, and molding pressure 5 MPa, the helical flow value (cm) of the thermosetting resin composition was measured. The results are shown in Table 3.

[0278] (Molding shrinkage)

[0279] According to JIS K-6911 (2006) 5.7, under the conditions of molding temperature 120°C, molding pressure 5MPa, and molding time 3 minutes, a compression molding machine (Co., Ltd.) was used. The compression molding process yielded disc-shaped test specimens (φ90mm×11mm), and the molding shrinkage rate was calculated. The test specimens were prepared using freshly mixed thermosetting resin compositions. The results are shown in Table 3.

[0280] (Mold making)

[0281] The stator was placed in a mold, and a thermosetting resin composition was injected. Molding was carried out at a molding temperature of 130°C, a molding pressure of 5 MPa, and a molding time of 5 minutes to obtain the molded stator. The filling properties during molding and the appearance of the molded stator from a crack perspective were evaluated according to the following criteria. The results are shown in Table 3.

[0282] Initial filling properties during mold stent forming

[0283] Visually inspect the appearance of the molded mold made using the freshly mixed thermosetting resin composition. A good condition is defined as the cured thermosetting resin composition completely filling the mold shape without any defects, while a condition with partial defects is defined as poor.

[0284] Changes in filler properties over time during molded stent forming

[0285] Visually observe the appearance of molded molds made from thermosetting resin compositions that have been mixed and stored at 20°C for 30 days. A state in which the cured thermosetting resin composition completely fills the mold shape without any defects is defined as good, and a state in which there are partial defects is defined as bad.

[0286] Initial Appearance of Mold Stator Based on Crack Perspective

[0287] Visually inspect the appearance of molded studs made using freshly mixed thermosetting resin composition. Determine if no cracks are present, and determine if cracks are present, as poor.

[0288] The Appearance Changes of Mold Stator Over Time Based on Crack Perspective

[0289] Visually inspect the appearance of molded studs made from thermosetting resin compositions that have been mixed and stored at 20°C for 30 days. Cases without cracks are classified as good, and cases with cracks are classified as bad.

[0290] (Thermal cycling test)

[0291] For molded studs made using freshly mixed thermosetting resin compositions, a thermal cycling tester (tester: TSA-71L-A, manufactured in 2010) was used. The company conducted thermal cycling tests in the atmosphere, with each cycle consisting of -40°C for 20 minutes and 140°C for 20 minutes. The tests were performed for 250 cycles, and the appearance of the mold stator was visually observed every 50 cycles to check for crack formation. The maximum number of cycles without crack formation is shown in Table 3.

[0292] [Table 3-1]

[0293]

[0294] [Table 3-2]

[0295]

[0296] <Examples 2-9, Comparative Examples 1-5>

[0297] Except for changing the types and compositions of the raw materials as described in Table 3, the thermosetting resin composition was prepared in the same manner as in Example 1. Then, various evaluations were performed in the same manner as in Example 1. The results are shown in Table 3. It should be noted that thermal cycling tests were not performed on Comparative Examples 1-5.

[0298] In Examples 1-9, the flowability of the thermosetting resin composition was adjusted to the desired range, and the filling properties during molding were good, resulting in molded studs with a good appearance covered by the molding material and free of defects and cracks. On the other hand, in Comparative Example 1, which did not use a thickener, and Comparative Example 2, which had insufficient styrene-butadiene rubber content, the filling properties were poor, and defects occurred in a portion of the molded stud. In Comparative Example 3, which contained an excessive amount of styrene-butadiene rubber, the flowability and filling properties could not be adjusted to the desired range, and defects occurred in a portion of the molded stud. In Comparative Example 3, the molding material cracked, and a molded stud with a good appearance was not obtained. In Comparative Example 4, which used magnesium oxide instead of styrene-butadiene rubber, the molding material cracked, and a molded stud with a good appearance was not obtained. Furthermore, the change in flowability over time could not be controlled, and the filling properties deteriorated after the change over time. In Comparative Example 5, which did not use (A) saturated polyester resin, the molding material cracked, and a molded stud with a good appearance was not obtained.

[0299] Symbol Explanation

[0300] 10 Electric motors

[0301] 11 Stator

[0302] 12 Stator Core

[0303] 13 coils

[0304] 14. Molding materials

[0305] 15 Rotors

[0306] 16 magnets

[0307] 17 Rotation axis

[0308] 18. Bodies of Revolution

[0309] 19. Bearings.

Claims

1. A molding die, having: Stator, the stator having a stator core and coils wound on the stator core; and The molding material covering the stator, in, The molding material is a cured product of a thermosetting resin composition containing (A) saturated polyester resin, (B) thermosetting resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, (F) inorganic filler, and (G) thickener. The thickener (G) is selected from one or more of styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS). In the thermosetting resin composition, when the total amount of the thermosetting resin (B) and the olefinic unsaturated monomer (C) is set to 100 parts by mass, the content of the thickener (G) is 0.8 to 9 parts by mass. The saturated polyester resin (A) is a condensation polymer of diol and saturated polybasic acid. The saturated polybasic acid includes aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids. In the (A) saturated polyester resin, the molar ratio of the structure derived from the aromatic saturated polybasic acid or its anhydride to the structure derived from the aliphatic saturated polybasic acid is 20:80 to 80:

20. The (A) saturated polyester resin comprises: block X as a condensation polymer of a diol and an aromatic saturated polyacid or its anhydride, and block Y as a condensation polymer of a diol and an aliphatic saturated polyacid, wherein the weight-average molecular weight of block X is 3000 to 5000.

2. The molding die as described in claim 1, wherein, The weight-average molecular weight of the saturated polyester resin (A) is 9500 to 13500.

3. The molding die as described in claim 1 or 2, wherein, The aromatic saturated polybasic acid constituting block X is selected from one or more of isophthalic acid and terephthalic acid.

4. The molding die as described in claim 1 or 2, wherein, The aliphatic saturated polyacid constituting the block Y is selected from one or more of succinic acid, adipic acid and sebacic acid.

5. The molding die as described in claim 1, wherein, The weight-average molecular weight of the thermosetting resin (B) is 10,000 to 50,000.

6. The molding die as described in claim 1, wherein, The thermosetting resin (B) contains unsaturated polyester resin. The unsaturated polyester resin is a condensation polymer of diol, unsaturated polybasic acid, and optionally saturated polybasic acid. The diol contains propylene glycol and neopentyl glycol.

7. The molding die as claimed in claim 1, wherein in the thermosetting resin composition, when the total amount of the thermosetting resin (B) and the olefinically unsaturated monomer (C) is set to 100 parts by mass, contain 5-30 parts by weight of the saturated polyester resin (A), The (B) thermosetting resin, 5-80 parts by weight, 20-95 parts by mass of the (C) olefinic unsaturated monomer, The (D) thermal polymerization initiator, 0.5-20 parts by weight, The (E) glass fiber, 5-200 parts by weight, and The (F) inorganic filler material is 50 to 1000 parts by weight.

8. An electric motor, comprising: The molding die according to any one of claims 1, 2 and 5 to 7; A rotor having a rotating shaft extending along its axial direction and a rotating body containing a magnetic component extending along the axial direction and fixed to the rotating shaft, the rotor being located inside the stator; and A bearing that rotatably supports the rotor.

9. A thermosetting resin composition comprising: (A) Saturated polyester resin, (B) Thermosetting resins, (C) Alkene unsaturated monomers, (D) Thermal polymerization initiator, (E) Glass fiber, (F) Inorganic filler materials, and (G) Thickener, in, The thickener (G) is selected from one or more of styrene-butadiene rubber (SBR), styrene-butadiene-styrene rubber (SBS), and styrene-ethylene-butadiene-styrene rubber (SEBS). When the total amount of the thermosetting resin (B) and the olefinic unsaturated monomer (C) is set to 100 parts by mass, the content of the thickener (G) is 0.8 to 9 parts by mass. The saturated polyester resin (A) is a condensation polymer of diol and saturated polybasic acid. The saturated polybasic acid includes aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids. In the (A) saturated polyester resin, the molar ratio of the structure derived from the aromatic saturated polybasic acid or its anhydride to the structure derived from the aliphatic saturated polybasic acid is 20:80 to 80:

20. The (A) saturated polyester resin comprises: block X as a condensation polymer of a diol and an aromatic saturated polyacid or its anhydride, and block Y as a condensation polymer of a diol and an aliphatic saturated polyacid, wherein the weight-average molecular weight of block X is 3000 to 5000.

10. The thermosetting resin composition of claim 9, wherein, The weight-average molecular weight of the saturated polyester resin (A) is 9500 to 13500.

11. The thermosetting resin composition of claim 9 or 10, wherein, When the total amount of the thermosetting resin (B) and the olefinic unsaturated monomer (C) is set to 100 parts by mass, contain 5-30 parts by weight of the saturated polyester resin (A), The (B) thermosetting resin, 5-80 parts by weight, 20-95 parts by mass of the (C) olefinic unsaturated monomer, The (D) thermal polymerization initiator, 0.5-20 parts by weight, The (E) glass fiber, 5-200 parts by weight, and The (F) inorganic filler material is 50 to 1000 parts by weight.

12. A molding material, which is a cured product of the thermosetting resin composition of claim 9 or 10.

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