Molded stator and electric motor

Abstract

A molded stator comprising: 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 comprising (A) a saturated polyester resin, (B) an unsaturated polyester resin, (C) an olefinic unsaturated monomer, (D) a thermal polymerization initiator, (E) glass fiber, and (F) an inorganic filler, wherein the (B) unsaturated polyester resin comprises at least a (B-1) unsaturated polyester resin, the (B-1) unsaturated polyester resin being a condensation polymer comprising a mixture of a diol and an unsaturated polybasic acid, and the (B-1) unsaturated polyester resin containing a structure derived from propylene glycol and a structure derived from neopentyl glycol.

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, there is a problem of insufficient strength in the cured molding resin, leading to cracking in the molded product.

[0008] This disclosure provides a molded stud covered with molding material that has a good appearance with no cracks.

[0009] Methods for solving problems

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

[0012] A molding die has:

[0013] A 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) unsaturated polyester resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, and (F) inorganic filler.

[0017] The above-mentioned (B) unsaturated polyester resin contains at least (B-1) unsaturated polyester resin.

[0018] The aforementioned (B-1) unsaturated polyester resin is a condensation polymer containing a mixture of diols and unsaturated polyacids.

[0019] The above-mentioned (B-1) unsaturated polyester resin contains structures derived from propylene glycol and structures derived from neopentyl glycol. [2]

[0021] The molding die as described in [1], wherein the molar ratio of the structure derived from propylene glycol to the structure derived from neopentyl glycol in the above (B-1) unsaturated polyester resin is 10:90 to 90:10. [3]

[0023] The molding die as described in [1] or [2], wherein the above-mentioned (B-1) unsaturated polyester resin further contains a structure derived from hydrogenated bisphenol A. [4]

[0025] The molding die as described in any one of [1] to [3], wherein the above-mentioned (B) unsaturated polyester resin further contains (B-2) unsaturated polyester resin,

[0026] The aforementioned (B-2) unsaturated polyester resin is a condensation polymer containing a mixture of diols and unsaturated polyacids.

[0027] The above-mentioned (B-2) unsaturated polyester resin contains a structure derived from propylene glycol but does not contain a structure derived from neopentyl glycol. [5]

[0029] The molding die as described in any one of [1] to [4], wherein the above-mentioned (B-1) unsaturated polyester resin contains a structure derived from a saturated polyacid. [6]

[0031] The molding die as described in [4], wherein the above-mentioned (B-2) unsaturated polyester resin contains a structure derived from saturated polyacids. [7]

[0033] The molding die as described in any one of [1] to [6], wherein the weight-average molecular weight of the (B-1) unsaturated polyester resin is 10,000 to 50,000. [8]

[0035] The mold stud as described in any one of [1] to [7], wherein the above-mentioned (A) saturated polyester resin is a condensation polymer comprising a mixture of diol and saturated polyacid,

[0036] The above-mentioned saturated polybasic acids include aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids. [9]

[0038] The molding die as described in [8], wherein 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.

[0039] 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]

[0041] The molding stent as described in [9], wherein the aromatic saturated polyacid constituting the block (X) is selected from one or more of isophthalic acid and terephthalic acid.

[11]

[0043] The molded stent as described in [9] or

[10] , wherein the aliphatic saturated polyacid constituting the block (Y) is selected from one or more of succinic acid, adipic acid and sebacic acid.

[12]

[0045] The molding die as described in any one of [1] to

[11] , wherein the weight-average molecular weight of the saturated polyester resin of (A) is 9500 to 13500.

[13]

[0047] The molding die as described in any one of [1] to

[12] , wherein, in the above-mentioned thermosetting resin composition, when the total amount of the above-mentioned (B) unsaturated polyester resin and the above-mentioned (C) olefin unsaturated monomer is set to 100 parts by mass,

[0048] contain

[0049] 5-30 parts by weight of the above-mentioned (A) saturated polyester resin

[0050] 20-80 parts by weight of the above-mentioned (B) unsaturated polyester resin

[0051] 80-20 parts by mass of the above-mentioned (C) olefinic unsaturated monomer

[0052] The above-mentioned (D) thermal polymerization initiator, 0.5-20 parts by weight,

[0053] The above-mentioned (E) glass fiber, 5 to 150 parts by weight, and

[0054] 50 to 1000 parts by weight of the above (F) inorganic filler material.

[14]

[0056] An electric motor, comprising:

[0057] The molded stent as described in any one of [1] to

[13] ;

[0058] 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

[0059] The bearings that rotatably support the aforementioned rotor.

[15]

[0061] A thermosetting resin composition comprising:

[0062] (A) Saturated polyester resin,

[0063] (B) Unsaturated polyester resin,

[0064] (C) Alkene unsaturated monomers,

[0065] (D) Thermal polymerization initiator,

[0066] (E) Glass fiber, and

[0067] (F) Inorganic filler materials,

[0068] in,

[0069] The above-mentioned (B) unsaturated polyester resin contains at least (B-1) unsaturated polyester resin.

[0070] The aforementioned (B-1) unsaturated polyester resin is a condensation polymer containing a mixture of diols and unsaturated polyacids.

[0071] The above-mentioned (B-1) unsaturated polyester resin contains structures derived from propylene glycol and structures derived from neopentyl glycol.

[16]

[0073] The thermosetting resin composition as described in

[15] , wherein the above-mentioned (B-1) unsaturated polyester resin further contains a structure derived from hydrogenated bisphenol A.

[17]

[0075] Thermosetting resin compositions as described in

[15] or

[16] , wherein the saturated polyester resin of (A) is a condensation polymer comprising a mixture of diol and saturated polyacid,

[0076] The aforementioned saturated polybasic acids include aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids.

[0077] 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.

[0078] 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.

[18]

[0080] The thermosetting resin composition as described in any one of

[15] to

[17] , wherein the total amount of the above-mentioned (B) unsaturated polyester resin and the above-mentioned (C) olefin unsaturated monomer is set to 100 parts by mass.

[0081] contain

[0082] 5-30 parts by weight of the above-mentioned (A) saturated polyester resin

[0083] 20-80 parts by weight of the above-mentioned (B) unsaturated polyester resin

[0084] 80-20 parts by mass of the above-mentioned (C) olefinic unsaturated monomer

[0085] The above-mentioned (D) thermal polymerization initiator, 0.5-20 parts by weight,

[0086] The above-mentioned (E) glass fiber, 5 to 150 parts by weight, and

[0087] 50 to 1000 parts by weight of the above (F) inorganic filler material.

[19]

[0089] A molding material, which is a cured product of any one of the thermosetting resin compositions described in

[15] to

[18] .

[0090] The effects of the invention

[0091] According to this disclosure, a molded stud covered with molding material can be provided, which has a good appearance without cracks. Attached Figure Description

[0092] Figure 1 This is a schematic cross-sectional view of an exemplary electric motor. Detailed Implementation

[0093] The embodiments of the present invention will now be described in detail. However, the present invention is not limited to the embodiments shown below.

[0094] 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.

[0095] 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.

[0096] In this specification, "thermosetting resin" refers to a resin that cures by forming a cross-linked structure when heated, indicating its state before curing.

[0097] 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.

[0098] 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.

[0099] Device: Shodex (trademark) GPC-101 ( )

[0100] Column: Shodex LF-804 (trademark) )

[0101] Column temperature: 40℃

[0102] Sample: 0.2% by mass tetrahydrofuran solution of the sample

[0103] Flow rate: 1 mL / min

[0104] Eluent: Tetrahydrofuran

[0105] Detector: Shodex (trademark) RI-71S )

[0106] 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.

[0107] <Electric motor>

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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 1 In 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.

[0112] <Modifier>

[0113] 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.

[0114] 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.

[0115] <Molding Materials>

[0116] 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.

[0117] <Thermosetting Resin Composition>

[0118] One embodiment of the thermosetting resin composition comprises (A) a saturated polyester resin, (B) an unsaturated polyester resin, (C) an olefinically unsaturated monomer, (D) a thermal polymerization initiator, (E) glass fiber, and (F) an inorganic filler. The (B) unsaturated polyester resin contains at least (B-1) unsaturated polyester resin, which is a condensation polymer comprising a mixture of diol and unsaturated polyacid, and contains structures derived from propylene glycol and neopentyl glycol. The cured thermosetting resin composition is suitable as a molding material for covering a stator. By using the cured thermosetting resin composition containing (B-1) unsaturated 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.

[0119] [(A) Saturated polyester resin]

[0120] (A) The saturated polyester resin is a condensation polymer of a polyol and a saturated polyacid. (A) The saturated polyester resin is preferably a condensation polymer comprising a mixture of a diol and a saturated polyacid, more preferably a condensation polymer comprising a mixture of a diol, an aromatic saturated polyacid or its anhydride, and an aliphatic saturated polyacid. (A) In the polyol-derived structure of the saturated polyester resin, the diol-derived structure is preferably 95 mol% or more, more preferably 98 mol% or more, and even more preferably 100 mol%. (A) In the polyol-derived structure of the saturated polyester resin, the upper limit of the diol-derived structure can be 100 mol% or 99 mol%. (A) In the saturated polyacid-derived structure of the saturated polyester resin, the structure derived from any one of an aromatic saturated polyacid, its anhydride, and an aliphatic saturated polyacid is preferably 95 mol% or more, more preferably 98 mol% or more, and even more preferably 100 mol%. (A) The upper limit of the structure of the saturated polyester resin derived from the saturated polybasic acid is 100 mol% or 99 mol%.

[0121] (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.

[0122] 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.

[0123] There are no particular limitations on polyols as long as they are compounds having two or more hydroxyl groups. Polyols are preferably selected from one or more diols and triols, 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; ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, and alkylene oxide modified bisphenol A; and glycerol. From the viewpoint of crack resistance during molding, polyoxyalkylene polyols are preferably selected from one or more alkylene glycols and polyoxyalkylene polyols, more preferably polyoxyalkylene glycols, and even more preferably from one or more diethylene glycol, dipropylene glycol, and triethylene glycol. From the viewpoint of improving the durability of molded articles, 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 the molar ratio of diethylene glycol to dipropylene glycol is not particularly limited, but 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 polyols can be used alone or in combination with two or more.

[0124] There are no particular limitations on saturated polybasic acids, as long as they are compounds without olefinic unsaturated bonds and have two or more carboxyl groups, or their anhydrides. Well-known saturated polybasic acids can be used. Saturated dibasic acids are preferred. 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 anhydrides of cyclic aliphatic saturated polybasic acids such as hexahydrophthalic anhydride. As an aromatic saturated polybasic acid or its anhydride, it is preferably selected from one or more aromatic saturated dibasic acids and their anhydrides, more preferably from one or more phthalic acid, phthalic anhydride, isophthalic acid, and terephthalic acid, and even more preferably from one or more isophthalic acid and terephthalic acid. As an aliphatic saturated polybasic acid, it is preferably an aliphatic saturated dibasic acid, more preferably an aliphatic saturated dibasic acid with 4 to 10 carbon atoms, and even more preferably from one or more succinic acid, adipic acid, and sebacic acid. From the viewpoint of crack resistance during molding, it is preferable to use one or more aromatic saturated polybasic acids, their anhydrides, and aliphatic saturated polybasic acids, more preferably using a combination of aromatic saturated polybasic acids or their anhydrides and aliphatic saturated polybasic acids, and even more preferably using a combination of one or more isophthalic acid and terephthalic acid and one or more isophthalic acid, adipic acid, and sebacic acid. Saturated polybasic acids can be used alone or in combination of two or more.

[0125] When aromatic saturated polybasic acids or their anhydrides are used in combination with aliphatic saturated polybasic acids, the proportion of the aromatic saturated polybasic acids or their anhydrides relative to their total is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. When aromatic saturated polybasic acids or their anhydrides are used in combination with aliphatic saturated polybasic acids, the proportion of the aromatic saturated polybasic acids or their anhydrides relative to their total is preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. When the proportion of aromatic saturated polybasic acids or their anhydrides is within the above range, the formability is better, and the properties of the cured product can be further improved.

[0126] When aromatic saturated polybasic acids or their anhydrides are used in combination with aliphatic saturated polybasic acids, the proportion of aliphatic saturated polybasic acids relative to their total content is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more. When aromatic saturated polybasic acids or their anhydrides are used in combination with aliphatic saturated polybasic acids, the proportion of aliphatic saturated polybasic acids relative to their total content is preferably 80 mol% or less, more preferably 70 mol% or less, and even more preferably 60 mol% or less. When the proportion of aliphatic saturated polybasic acids is within the above range, crack resistance can be further improved.

[0127] When using aromatic saturated polybasic acid or its anhydride in combination with aliphatic saturated polybasic acid, in (A) saturated polyester resin, the molar ratio of the structure derived from aromatic saturated polybasic acid or its anhydride to the structure derived from aliphatic saturated polybasic acid is preferably 20:80 to 80:20, more preferably 30:70 to 70:30, and even more preferably 40:60 to 60:40.

[0128] When aromatic saturated polybasic acids or their anhydrides are used in combination with aliphatic saturated polybasic acids, the structures derived from them can be uniformly dispersed in the molecules of (A) saturated polyester resin, or they can be distributed separately in the molecules. From the viewpoint of crack resistance during molding, it is preferable that (A) saturated polyester resin includes blocks (X) and blocks (Y), wherein block (X) is a condensation polymer of a diol and an aromatic saturated polybasic acid or its anhydride, and the weight-average molecular weight of block (X) is 3000 to 5000, and block (Y) is a condensation polymer of a diol and an aliphatic saturated polybasic acid. In (A) saturated polyester resin containing blocks (X) and blocks (Y), the molar ratio of structures derived from aromatic saturated polybasic acids or their anhydrides to structures derived from aliphatic saturated polybasic acids is preferably 20:80 to 80:20, more preferably 30:70 to 70:30, and even more preferably 40:60 to 60:40.

[0129] In (A) saturated polyester resin containing blocks (X) and blocks (Y), the portion outside blocks (X) and blocks (Y) may contain structures derived from aromatic saturated polybasic acids or their anhydrides.

[0130] The weight-average molecular weight of the block (X) is preferably 3000 or more, more preferably 3500 or more. The weight-average molecular weight of the block (X) is preferably 5000 or less, more preferably 4500 or less. When the weight-average molecular weight of the block (X) is within the above range, the crack resistance during molding is better.

[0131] 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.

[0132] 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.

[0133] Preferred combinations of polyols and saturated polyacids include glycols and saturated diacids, more preferably polyoxyalkylene glycols and saturated diacids. 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 particularly good crack resistance during molding and are therefore preferred.

[0134] 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) unsaturated polyester resin and the dispersibility of components (C) to (F) are improved, further 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.

[0135] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester 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) unsaturated polyester 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) unsaturated polyester 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. If 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. If 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 mechanical properties of the cured product.

[0136] (A) Synthesis method of saturated polyester resin)

[0137] (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.

[0138] 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.

[0139] The equivalent of the hydroxyl groups of the polyol relative to the total carboxyl groups of the saturated polyacid is preferably set in the range of 0.9 to 1.2.

[0140] When an aromatic saturated polybasic acid or its anhydride is used in combination with an aliphatic saturated polybasic acid, the structure derived from them can be uniformly dispersed within the molecules of the (A) saturated polyester resin. Such a (A) saturated polyester resin can be obtained by esterification reaction in which both are added to a reaction vessel in a single step.

[0141] From the perspective of crack resistance during molding, it is preferable that the structures derived from aromatic saturated polybasic acids or their anhydrides and those derived from aliphatic saturated polybasic acids are respectively predominantly distributed in the molecule. 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 is consumed, another saturated polybasic acid is added to the reaction vessel to carry out an esterification reaction until the desired weight-average molecular weight is obtained. For example, such (A) saturated polyester resin can be synthesized as follows: first, an equimolar amount of a polyol, the aromatic saturated polybasic acid or its anhydride, and an aliphatic saturated polybasic acid 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 is consumed, an aliphatic saturated polybasic acid is added to the reaction vessel to carry out an esterification reaction.

[0142] A saturated polyester resin (A) comprising a block (X) as a condensation polymer of a diol and an aromatic saturated polybasic acid or its anhydride and a block (Y) as a condensation polymer of a diol and an aliphatic saturated polybasic acid can be synthesized, for example, as follows: first, an equimolar amount of a diol and an aromatic saturated polybasic acid or its anhydride and an aliphatic saturated polybasic acid are added to a reaction vessel to carry out an esterification reaction; after a certain amount of 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.

[0143] 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.

[0144] [(B) Unsaturated polyester resin]

[0145] (B) 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. (B) The unsaturated polyester resin contains at least (B-1) unsaturated polyester resin, which is a condensation polymer comprising a mixture of a glycol and an unsaturated polyacid, and contains structures derived from propylene glycol and neopentyl glycol. (B) The unsaturated polyester resin may further contain (B-2) unsaturated polyester resin, which is a condensation polymer comprising a mixture of a glycol and an unsaturated polyacid, and contains structures derived from propylene glycol but not from neopentyl glycol. (B) The unsaturated polyester resin may contain unsaturated polyester resins other than (B-1) and (B-2). By using (B) unsaturated polyester resin, cured products with excellent mechanical strength and heat resistance can be obtained.

[0146] It should be noted that, in this disclosure, styrene monomers and the like contained in commercially available unsaturated polyester resins are classified as (C) olefinic unsaturated monomers.

[0147] (B) The content of (B-1) unsaturated polyester resin in the unsaturated polyester resin is preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. When 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 unsaturated polyester resin. For example, it can be 100% by mass, 97% by mass, or 95% by mass.

[0148] When using both (B-1) and (B-2) unsaturated polyester resins, the total content of (B-1) and (B-2) unsaturated polyester resins in the (B) unsaturated polyester resin is preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. When the total content of (B-1) and (B-2) unsaturated polyester resins is 75% by mass or more, appropriate moldability, flowability, and curing shrinkage can be ensured. There is no particular upper limit to the total content of (B-1) and (B-2) unsaturated polyester resins in the (B) unsaturated polyester resin. For example, it can be 100% by mass, 97% by mass, or 95% by mass.

[0149] When using both (B-1) unsaturated polyester resin and (B-2) unsaturated polyester resin, the proportion of (B-1) unsaturated polyester resin is preferably 20 to 80% by mass, more preferably 30 to 70% by mass, and even more preferably 40 to 60% by mass, relative to the total of (B-1) unsaturated polyester resin and (B-2) unsaturated polyester resin.

[0150] In another embodiment, the content of (B-1) unsaturated polyester resin in (B) is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more. The content of (B-1) unsaturated polyester resin in (B) is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less. The content of (B-2) unsaturated polyester resin in (B) is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 10% by mass or more. The content of (B-2) unsaturated polyester resin in (B) is preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 60% by mass or less.

[0151] (B) The weight-average molecular weight of the unsaturated polyester resin is preferably 2,000 to 50,000, more preferably 5,000 to 50,000, even more preferably 10,000 to 50,000, and still more preferably 13,000 to 35,000. When the weight-average molecular weight is within the above range, the generation of cracks 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 unsaturated polyester resin (B) within the above range, the compatibility with the saturated polyester resin (A) and the dispersibility of components (C) to (F) are improved, and the generation of cracks during molding is further suppressed. It should be noted that the weight-average molecular weight of the unsaturated polyester resin (B) refers to the weight-average molecular weight of the resin in the state before curing.

[0152] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (B) unsaturated polyester resin is preferably 20 parts by mass or more, more preferably 30 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) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (B) unsaturated polyester resin is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 60 parts by mass or less. When the content of (B) unsaturated polyester resin in the thermosetting resin composition is 20 parts by mass or more, the cured product exhibits good mechanical strength. When the content of (B) unsaturated polyester 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.

[0153] <(B-1) Unsaturated polyester resin>

[0154] (B-1) Unsaturated polyester resins are condensation polymers comprising a mixture of diols and unsaturated polybasic acids, containing structures derived from propylene glycol and neopentyl glycol. (B-1) Unsaturated polyester resins may also contain structures derived from saturated polybasic acids. (B-1) Unsaturated polyester resins may also contain structures derived from diols other than propylene glycol and neopentyl glycol.

[0155] (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.

[0156] Examples of diols other than propylene glycol and neopentyl glycol include alkylene glycols such as ethylene glycol, butanediol, pentylene glycol, hexanediol, 2-methyl-1,3-propanediol, 1,4-cyclohexanediol, and hydrogenated bisphenol A; polyoxyalkylene glycols such as diethylene glycol, dipropylene glycol, triethylene glycol, tetraethylene glycol, and polyethylene glycol; bisphenol A; ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, and epoxide-modified bisphenol A. 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, butanediol, pentylene glycol, and hexanediol. From the viewpoint of chemical resistance, hydrogenated bisphenol A is preferred. Other diols may be used alone or in combination of two or more.

[0157] In the (B-1) unsaturated polyester resin, the molar ratio of the structure derived from propylene glycol to the structure derived from neopentyl glycol is preferably 10:90 to 90:10, more preferably 15:85 to 85:15, and even more preferably 20:80 to 80:20.

[0158] In the diol-derived structure of the (B-1) unsaturated polyester resin, the propylene glycol-derived structure is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more. In the diol-derived structure of the (B-1) unsaturated polyester resin, the propylene glycol-derived structure is preferably 90 mol% or less, more preferably 85 mol% or less, and even more preferably 80 mol% or less.

[0159] In the diol-derived structure of the (B-1) unsaturated polyester resin, the neopentyl glycol-derived structure is preferably 10 mol% or more, more preferably 15 mol% or more, and even more preferably 20 mol% or more. In the diol-derived structure of the (B-1) unsaturated polyester resin, the neopentyl glycol-derived structure is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less.

[0160] In the diol-derived structure of the (B-1) unsaturated polyester resin, the total ratio of the structure derived from propylene glycol to the structure derived from neopentyl glycol is preferably 70 mol% or more, more preferably 75 mol% or more, and even more preferably 80 mol% or more. In the diol-derived structure of the (B-1) unsaturated polyester resin, the total ratio of the structure derived from propylene glycol to the structure derived from neopentyl glycol can be 100 mol% or less, 95 mol% or less, or 90 mol% or less.

[0161] In the diol-derived structure of the (B-1) unsaturated polyester resin, the structure derived from other diols can be 0 mol% or more, preferably 5 mol% or more, and more preferably 10 mol% or more. In the diol-derived structure of the (B-1) unsaturated polyester resin, the structure derived from other diols is preferably 30 mol% or less, more preferably 25 mol% or less, and even more preferably 20 mol% or less.

[0162] (B-1) The unsaturated polyester resin may also contain a structure derived from a polyol having three or more hydroxyl groups. Examples of polyols having three or more hydroxyl groups include glycerol. In the structure of the (B-1) unsaturated polyester resin derived from a polyol having two or more hydroxyl groups, the structure derived from a diol is preferably 95 mol% or more, more preferably 98 mol% or more, and even more preferably 100 mol%. In the structure of the (B-1) unsaturated polyester resin derived from a polyol having two or more hydroxyl groups, the upper limit of the structure derived from a diol may be 100 mol% or 99 mol%.

[0163] 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 or their anhydrides with 4 to 6 carbon atoms are preferred because they are less expensive and can produce thermosetting resin compositions with superior mechanical strength and heat resistance in the cured product. 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, they are selected from one or more of fumaric acid, maleic acid, maleic anhydride, and itaconic acid; even more preferably, they are selected from one or more of fumaric acid and maleic anhydride. Unsaturated polybasic acids can be used alone or in combination of two or more.

[0164] 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.

[0165] (B-1) The weight-average molecular weight of the unsaturated polyester resin is not particularly limited. (B-1) The weight-average molecular weight of the unsaturated polyester resin is preferably 2,000 or more, more preferably 5,000 or more, further preferably 10,000 or more, and particularly preferably 13,000 or more. (B-1) The weight-average molecular weight of the unsaturated polyester resin is preferably 50,000 or less, more preferably 35,000 or less. (B-1) The weight-average molecular weight of the 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 (B-1) unsaturated polyester resin to the above range, the compatibility with (A) saturated polyester resin and the dispersibility of (C) to (F) components are improved, thereby further suppressing the generation of cracks during molding.

[0166] 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.

[0167] The degree of unsaturation of unsaturated polyester resin can be calculated using the following formula, based on the number of moles of unsaturated polybasic acids and saturated polybasic acids used as raw materials.

[0168] 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

[0169] <Unsaturated polyester resin (B-2)>

[0170] (B-2) Unsaturated polyester resins are condensation polymers comprising a mixture of diols and unsaturated polybasic acids, containing structures derived from propylene glycol but not from neopentyl glycol. (B-2) Unsaturated polyester resins may also contain structures derived from saturated polybasic acids. (B-2) Unsaturated polyester resins may also contain structures derived from diols other than propylene glycol and neopentyl glycol.

[0171] (B-2) unsaturated polyester resin can be used alone or in combination with two or more types. By using (B-2) unsaturated polyester resin, the shrinkage rate during molding can be adjusted.

[0172] Specific and preferred examples of diols other than propylene glycol and neopentyl glycol are the same as those for (B-1) unsaturated polyester resin. Other diols may be used alone or in combination of two or more.

[0173] In the diol-derived structure of the (B-2) unsaturated polyester resin, the propylene glycol-derived structure is preferably 30 mol% or more, more preferably 50 mol% or more, and even more preferably 70 mol% or more. In the diol-derived structure of the (B-2) unsaturated polyester resin, the propylene glycol-derived structure can be 100 mol% or less, 90 mol% or less, or 80 mol% or less.

[0174] In the diol-derived structure of the (B-2) unsaturated polyester resin, the structure derived from other diols can be 0 mol% or more, 3 mol% or more, or 5 mol% or more. In the diol-derived structure of the (B-2) unsaturated polyester resin, the structure derived from other diols is preferably 30 mol% or less, more preferably 20 mol% or less, and even more preferably 10 mol% or less.

[0175] (B-2) The unsaturated polyester resin may also contain a structure derived from a polyol having three or more hydroxyl groups. Examples of polyols having three or more hydroxyl groups include glycerol. In the structure of the (B-2) unsaturated polyester resin derived from a polyol having two or more hydroxyl groups, the structure derived from a diol is preferably 95 mol% or more, more preferably 98 mol% or more, and even more preferably 100 mol%. In the structure of the (B-2) unsaturated polyester resin derived from a polyol having two or more hydroxyl groups, the upper limit of the structure derived from a diol may be 100 mol% or 99 mol%.

[0176] Specific and preferred examples of unsaturated polybasic acids are the same as those for (B-1) unsaturated polyester resin. Unsaturated polybasic acids can be used alone or in combination with two or more.

[0177] Specific and preferred examples of saturated polybasic acids are the same as those of (B-1) unsaturated polyester resin. Saturated polybasic acids can be used alone or in combination with two or more.

[0178] The weight-average molecular weight of (B-2) unsaturated polyester resin is not particularly limited. The weight-average molecular weight of (B-2) 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 even more 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 subject to any theoretical constraints, it can be considered that by setting the weight-average molecular weight of (B-2) unsaturated polyester resin to the above range, the compatibility with (A) saturated polyester resin and the dispersibility of components (C) to (F) are improved, further suppressing the cracking during molding.

[0179] The degree of unsaturation of the (B-2) 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-2) unsaturated polyester resin has better moldability.

[0180] (B) Synthesis method of unsaturated polyester resin)

[0181] (B) Unsaturated polyester resin can be synthesized using the above-mentioned raw materials by a known method. The various conditions for synthesizing (B) unsaturated polyester resin are appropriately set according to the raw materials used and their quantities.

[0182] 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.

[0183] To increase the reaction rate and thus the molecular weight, 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.

[0184] [(C) olefinic unsaturated monomers]

[0185] (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.

[0186] 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) unsaturated polyester resin, vinyl compounds are preferred, more preferably selected from one or more of styrene, vinyltoluene, tert-butylstyrene, and methoxystyrene, and even more preferably styrene.

[0187] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester 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 30 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) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (C) olefinically unsaturated monomer is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 60 parts by mass or less. If 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. If the content of (C) olefinically unsaturated monomer in the thermosetting resin composition is 80 parts by mass or less, the cured product has good mechanical strength.

[0188] (D) Thermal polymerization initiator

[0189] (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.

[0190] 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.

[0191] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester 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) unsaturated polyester 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 good. 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.

[0192] [(E) Glass fiber]

[0193] (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.

[0194] (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.

[0195] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester 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 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) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (E) glass fiber is preferably 150 parts by mass or less, more preferably 100 parts by mass or less, and even more preferably 50 parts by mass or less. If 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. If the content of (E) glass fiber in the thermosetting resin composition is 150 parts by mass or less, the (E) glass fiber is more uniformly dispersed in the thermosetting resin composition, and a homogeneous cured product can be produced.

[0196] [(F) Inorganic filler materials]

[0197] As the (F) inorganic filler material, particulate substances known in the art of this invention 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.

[0198] Examples of inorganic fillers (F) include calcium carbonate, silicon dioxide, aluminum oxide, aluminum hydroxide, barium sulfate, calcium sulfate, calcium hydroxide, calcium oxide, magnesium oxide, magnesium 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.

[0199] (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.

[0200] It should be noted that, in this specification, "average particle size" refers to the particle size distribution measured using 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.

[0201] (F) There are no particular restrictions on the shape of inorganic filler materials. Examples include approximately spherical, ellipsoidal, scaly, and amorphous shapes.

[0202] In the thermosetting resin composition, when the total amount of (B) unsaturated polyester 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) unsaturated polyester 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 500 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.

[0203] (G) Other low-shrinkage agents

[0204] The thermosetting resin composition may contain (G) other low-shrinkage agents besides saturated polyester resin, as needed. There are no particular limitations on (G) other low-shrinkage agents; low-shrinkage agents known in the art of this invention may be used. Thermoplastic resins are preferred as (G) other low-shrinkage agents. Examples of (G) other low-shrinkage agents include, for example, polystyrene, polyethylene, polymethyl methacrylate, polyvinyl acetate, polycaprolactone, styrene-butadiene rubber, etc. Among these, polystyrene is preferred from the viewpoint of reducing the shrinkage rate of the cured product. (G) 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) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (G) other low-shrinkage agents 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) unsaturated polyester resin and (C) olefinically unsaturated monomer is set to 100 parts by mass, the content of (G) other low-shrinkage agents can be 30 parts by mass or less, 20 parts by mass or less, or 10 parts by mass or less. When the content of (G) other low-shrinkage agents 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 (G) other low-shrinkage agents in the thermosetting resin composition is 30 parts by mass or less, the moldability of the thermosetting resin composition and the mechanical properties of the cured product are better.

[0206] [(H) Release agent]

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

[0208] The content of (H) release agent, relative to 100 parts by weight of (B) unsaturated polyester resin, 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. When the content of (H) release agent is 1 part by weight or more, the cured product exhibits good demolding properties during mold forming, resulting in good manufacturability of the product. On the other hand, when the content of (H) release agent is 40 parts by weight or less, there is 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, dethickening agents and other viscosity modifiers, 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] Thickeners are compounds that exhibit a thickening effect, excluding (F) inorganic fillers; examples include isocyanate compounds. Thickeners can be used alone or in combination of two or more. The content of the thickener can be adjusted appropriately according to the required workability, flowability, etc., of the thermosetting resin composition.

[0212] 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.

[0213] 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.

[0214] <Method for manufacturing thermosetting resin compositions>

[0215] Thermosetting resin compositions can be manufactured by mixing (A) saturated polyester resin, (B) unsaturated polyester resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, and (F) inorganic filler, and (G) other low-shrinkage agents, (H) mold release agents and other additives as optional components as needed.

[0216] 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.

[0217] There are no particular restrictions on the order in which the components are mixed when manufacturing a thermosetting resin composition. For example, it is preferable to mix the (B) unsaturated polyester resin with a portion or all of the (C) olefin unsaturated monomer 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 (C) olefin unsaturated monomer may be premixed with the (B) unsaturated polyester resin to function as a solvent, dispersion medium, etc.

[0218] <Methods for Manufacturing Molding Materials>

[0219] 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.

[0220] <Method for manufacturing mold studs>

[0221] 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.

[0222] 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.

[0223] Example

[0224] The present invention will be described in more detail below through examples and comparative examples, but the present invention is not limited to the following examples.

[0225] (A) An example of the synthesis of saturated polyester resin is shown below.

[0226] The following substances were used as raw materials.

[0227] Diol:

[0228] diethylene glycol ( )

[0229] Dipropylene glycol ( )

[0230] Saturated polyacids:

[0231] isophthalic acid ( )

[0232] adipic acid ( )

[0233] [Synthesis example 1]

[0234] 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.

[0235] [Table 1]

[0236]

[0237] [Synthesis Examples 2 to 5]

[0238] 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.

[0239] (B) An example of the synthesis of unsaturated polyester resin is shown below.

[0240] The following substances were used as raw materials.

[0241] Diol:

[0242] Propylene glycol ( Co., Ltd.)

[0243] Neopentyl glycol ( Co., Ltd.)

[0244] Hydrogenated bisphenol A ( Co., Ltd.)

[0245] Unsaturated polyacids:

[0246] Maleic anhydride ( Co., Ltd.)

[0247] fumaric acid ( Co., Ltd.)

[0248] Saturated polyacids:

[0249] isophthalic acid ( Co., Ltd.)

[0250] [Synthesis Example 6] (B-1) Synthesis of Unsaturated Polyester Resin

[0251] 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 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.

[0252] [Table 2]

[0253]

[0254] [Synthetic Examples 7-8] (B-1) Synthesis of Unsaturated Polyester Resin

[0255] 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.

[0256] [Synthetic Examples 9-11] (B-2) Synthesis of Unsaturated Polyester Resins

[0257] 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.

[0258] The following substances were used in other ingredients.

[0259] (C) Alkene unsaturated monomers:

[0260] Styrene (Idemitsu Kosan Co., Ltd.)

[0261] (D) Thermal polymerization initiator:

[0262] · (Trademark) I (Tertiary hexyl peroxide isopropyl carbonate, Nippon Oil Co., Ltd.)

[0263] (E) Glass fiber:

[0264] • Chopped strand ECS-03B173 / P9 (glass chopped strands, fiber diameter 13μm, fiber length 3.0mm, Nippon Electric Glass Co., Ltd.)

[0265] (F) Inorganic filler materials:

[0266] · 1200 (Calcium carbonate, average particle size 1.80 μm, Bikita Powder Chemical Industry Co., Ltd.)

[0267] Calcium hydroxide ( Chemical Co., Ltd.)

[0268] (G) Other low-shrinkage agents:

[0269] •PS MS-200 (Polystyrene, Sekisui Chemicals Co., Ltd.)

[0270] <Example 1>

[0271] (Preparation of thermosetting resin compositions)

[0272] The following were added to a double-arm kneader: 27 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) olefin unsaturated monomer (16 parts by mass of saturated polyester resin and 11 parts by mass of styrene); 85 parts by mass of a mixture of unsaturated polyester resin and styrene obtained from Synthesis Example 6, which served as (B) unsaturated polyester resin and (C) olefin unsaturated monomer (51 parts by mass of unsaturated polyester resin and 34 parts by mass of styrene); 4 parts by mass of styrene, which served as (C) olefin unsaturated monomer; and (D) a thermal polymerization initiator. (Trademark) I 4 parts by weight; as (E) chopped strands of glass fiber ECS-03B173 / P9 36 parts by weight; as (F) inorganic filler material A thermosetting resin composition was prepared by mixing 1200 parts by weight of 390 parts by weight of calcium hydroxide and 0.4 parts by weight of polystyrene as (G) other low shrinkage agents, at 30°C for 30 minutes.

[0273] (Viscosity)

[0274] The viscosity of the freshly mixed thermosetting resin composition was evaluated using a flow tester. Specifically, the flow tester viscosity (Pa·s) of the thermosetting resin composition was measured using a flow tester viscometer (machine: CFT-500D, manufactured in 2011, Shimadzu Corporation) with a φ1.5mm × 10mm mold, under conditions of heating temperature 70°C and load 7MPa. The results are shown in Table 3.

[0275] (Initial molding shrinkage)

[0276] 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.

[0277] (Changes in molding shrinkage over time)

[0278] 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. Disc-shaped test specimens (φ90mm×11mm) were obtained by compression molding, and the molding shrinkage rate was calculated. The test specimens were prepared using a thermosetting resin composition that had been mixed and stored at 20°C for 30 days. The results are shown in Table 3.

[0279] (Mold making)

[0280] 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.

[0281] Initial filling properties during mold stent forming

[0282] 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.

[0283] Changes in filler properties over time during molded stent forming

[0284] 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.

[0285] Initial Appearance of Mold Stator Based on Crack Perspective

[0286] 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.

[0287] The Appearance Changes of Mold Stator Over Time Based on Crack Perspective

[0288] 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.

[0289] (Thermal cycling test)

[0290] For molded studs made using thermosetting resin compositions that have been mixed and stored at 20°C for 30 days, 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.

[0291] [Table 3-1]

[0292]

[0293] [Table 3-2]

[0294]

[0295] <Examples 2-9, Comparative Examples 1-3>

[0296] Except for changing the composition 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 for Comparative Examples 1-3.

[0297] Symbol Explanation

[0298] 10 Electric motors

[0299] 11 Stator

[0300] 12 Stator Core

[0301] 13 coils

[0302] 14. Molding materials

[0303] 15 Rotors

[0304] 16 magnets

[0305] 17 Rotation axis

[0306] 18. Solids of Revolution

[0307] 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) unsaturated polyester resin, (C) olefinic unsaturated monomer, (D) thermal polymerization initiator, (E) glass fiber, and (F) inorganic filler. The (B) unsaturated polyester resin contains at least (B-1) unsaturated polyester resin. The (B-1) unsaturated polyester resin is a condensation polymer comprising a mixture of diol and unsaturated polyacid. The (B-1) unsaturated polyester resin contains structures derived from propylene glycol and structures derived from neopentyl glycol.

2. The molding die as described in claim 1, wherein, In the (B-1) unsaturated polyester resin, the molar ratio of the structure derived from propylene glycol to the structure derived from neopentyl glycol is 10:90 to 90:

10.

3. The molding die as described in claim 1, wherein, The (B-1) unsaturated polyester resin also contains a structure derived from hydrogenated bisphenol A.

4. The molding die as described in claim 1, wherein, The (B) unsaturated polyester resin also contains (B-2) unsaturated polyester resin. The (B-2) unsaturated polyester resin is a condensation polymer comprising a mixture of diol and unsaturated polyacid. The (B-2) unsaturated polyester resin contains a structure derived from propylene glycol but does not contain a structure derived from neopentyl glycol.

5. The molding die as described in claim 1, wherein, The (B-1) unsaturated polyester resin contains a structure derived from saturated polybasic acids.

6. The molding die as described in claim 4, wherein, The (B-2) unsaturated polyester resin contains a structure derived from saturated polybasic acids.

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

8. The molding die as described in claim 1, wherein, The (A) saturated polyester resin is a condensation polymer comprising a mixture of diol and saturated polyacid. The saturated polybasic acid includes aromatic saturated polybasic acids or their anhydrides, as well as aliphatic saturated polybasic acids.

9. The molding die as described in claim 8, wherein, 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 molding die as described in claim 9, wherein, The aromatic saturated polybasic acid constituting block X is selected from one or more of isophthalic acid and terephthalic acid.

11. The molding stent as described in claim 9, wherein, The aliphatic saturated polyacid constituting the block Y is selected from one or more of succinic acid, adipic acid and sebacic acid.

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

13. The molding die as claimed in claim 1, wherein in the thermosetting resin composition, when the total amount of the (B) unsaturated polyester resin and the (C) olefinically unsaturated monomer is set to 100 parts by mass, contain 5-30 parts by weight of the saturated polyester resin (A), 20-80 parts by weight of the unsaturated polyester resin (B), 80-20 parts by weight of the (C) olefinic unsaturated monomer, The (D) thermal polymerization initiator, 0.5-20 parts by weight, The (E) glass fiber, 5-150 parts by weight, and The (F) inorganic filler material is 50 to 1000 parts by weight.

14. An electric motor, comprising: The molding die according to any one of claims 1 to 13; 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 The bearings that rotatably support the rotor.

15. A thermosetting resin composition comprising: (A) Saturated polyester resin, (B) Unsaturated polyester resin, (C) Alkene unsaturated monomers, (D) Thermal polymerization initiator, (E) Glass fiber, and (F) Inorganic filler materials, in, The (B) unsaturated polyester resin contains at least (B-1) unsaturated polyester resin. The (B-1) unsaturated polyester resin is a condensation polymer comprising a mixture of diol and unsaturated polyacid. The (B-1) unsaturated polyester resin contains structures derived from propylene glycol and structures derived from neopentyl glycol.

16. The thermosetting resin composition of claim 15, wherein, The (B-1) unsaturated polyester resin also contains a structure derived from hydrogenated bisphenol A.

17. The thermosetting resin composition of claim 15, wherein, The (A) saturated polyester resin is a condensation polymer comprising a mixture of diol and saturated polyacid. 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.

18. The thermosetting resin composition of claim 15, wherein, When the total amount of the (B) unsaturated polyester resin and the (C) olefinic unsaturated monomer is set to 100 parts by mass, contain 5-30 parts by weight of the saturated polyester resin (A), 20-80 parts by weight of the unsaturated polyester resin (B), 80-20 parts by weight of the (C) olefinic unsaturated monomer, The (D) thermal polymerization initiator, 0.5-20 parts by weight, The (E) glass fiber, 5-150 parts by weight, and The (F) inorganic filler material is 50 to 1000 parts by weight.

19. A molding material, which is a cured product of the thermosetting resin composition according to any one of claims 15 to 18.

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