JP5156249B2 - Manufacturing method of integrated magnet body - Google Patents

Description

  The present invention relates to a method for manufacturing an integrated magnet body, which is used in an electric vehicle motor or the like and is formed by stacking and integrating a plurality of magnet pieces.

In recent years, an electric vehicle (EV) has been put into practical use as a next-generation vehicle. The EV motor includes a so-called IPM (Interior) in which a magnet such as a rare earth permanent magnet represented by an R—Fe—B permanent magnet (R: rare earth element) is embedded in a rotor formed of a silicon steel plate or the like. There are brushless motors called Permanent Magnet Motor (SRM) and Synchronous Reluctance Motor (SRM), but in recent years, with the progress of EV research and development, these motors have become smaller, lighter, higher output, higher efficiency and higher reliability. Sex is required.
When an AC magnetic field is applied to the magnet, eddy current is generated and eddy current loss occurs. Therefore, the magnet used for IPM needs to reduce the eddy current generated in the magnet. Therefore, a method has been proposed in which a magnet is divided into a plurality of magnet pieces, and the magnets are laminated in a state of being electrically insulated from each other, and used as an integrated magnet body.
For example, in Patent Document 1, a film having excellent insulating properties even in a thin film is formed between magnet pieces and the film of the insulating film with respect to the film thickness of the insulating film and the total length in the stacking direction of the integrated magnet body A method for setting the ratio of the total thickness to a specific value is described. Patent Document 2 describes a method of laminating magnet pieces, which have been previously provided with a margin for processing, and then laminating them, performing a finishing process after integration, grinding the processing margin, and then processing the whole with an insulating coating. ing.
International Publication No. 01/95460 Pamphlet JP 2003-134750 A

By the way, since the magnet used for IPM is often inserted into a slot provided in a rotor formed of a silicon steel plate or the like, high dimensional accuracy is required. Furthermore, it must be excellent in corrosion resistance and adhesive strength. Therefore, when using an integrated magnet body, it is required that the integrated magnet body as a whole has these characteristics as well as providing insulation between the individual magnet bodies. However, in order to manufacture an integrated magnet body that satisfies these requirements, there is a problem that the method described in Patent Document 1 requires, for example, strict film thickness management of the insulating coating. The method described in Patent Document 2 has a problem that the manufacturing process is many and complicated because finishing is required.
Accordingly, an object of the present invention is to provide a simple method for producing an integrated magnet body having high dimensional accuracy and excellent in corrosion resistance and adhesive strength.

As a result of intensive studies in view of the above points, the present inventors include a thermosetting resin composition composed of an epoxy resin having a sulfonium group and a propargyl group, and the minimum value of the complex viscosity η ^* in the thermosetting process. It has been found that by using a cationic electrodeposition paint having a Pa of 10 Pa · s or more, an integrated magnet body having high dimensional accuracy and excellent in corrosion resistance and adhesive strength can be easily produced.

The present invention made on the basis of the above knowledge is a manufacturing method of an integrated magnet body formed by laminating and integrating a plurality of magnet pieces as described in claim 1,
Step (1): A thermosetting resin composition comprising an epoxy resin having a sulfonium group and a propargyl group is included, and the minimum value of the complex viscosity η ^* in the thermosetting process is 10 Pa · s or more and the upper limit is 500 Pa · s . A process of electrodeposition coating a certain cationic electrodeposition paint on the surface of each magnet piece,
Step (2): a step of temporarily drying the individual magnet pieces electrodeposited in step (1),
Step (3): A step of laminating the individual magnet pieces temporarily dried in Step (2),
Step (4): A step of heating the laminated body composed of a plurality of magnet pieces laminated in Step (3) to complete the thermosetting of the thermosetting resin, and bonding and integrating the magnet pieces,
It is characterized by including at least.
The manufacturing method according to claim 2 is characterized in that, in the manufacturing method according to claim 1, temporary drying in the step (2) is performed at 40 to 120 ° C.
The manufacturing method according to claim 3 is the manufacturing method according to claim 1 or 2, wherein the heating in the step (4) is performed at 130 to 250 ° C.
The production method according to claim 4 is characterized in that, in the production method according to any one of claims 1 to 3, the cationic electrodeposition paint further contains crosslinked resin particles.
The manufacturing method according to claim 5 is characterized in that, in the manufacturing method according to claim 4, the content of the crosslinked resin particles is 1 to 30% by weight with respect to the resin solid content in the paint.
The manufacturing method according to claim 6 is characterized in that, in the manufacturing method according to any one of claims 1 to 5, the cationic electrodeposition paint further comprises insulating spherical particles.
The manufacturing method according to claim 7 is characterized in that, in the manufacturing method according to claim 6, the insulating particles are at least one selected from alumina particles, silica particles, and glass beads.
The manufacturing method according to claim 8 is the manufacturing method according to claim 6 or 7, characterized in that the insulating particles are spherical with a D10% diameter of 5 μm or more and a D90% diameter of 100 μm or less.
The manufacturing method according to claim 9 is the manufacturing method according to any one of claims 6 to 8, wherein the content of the insulating particles in the cationic electrodeposition coating is 1 to 30% by volume. .
Moreover, the integrated magnet body of this invention is manufactured by the manufacturing method of Claim 1 as described in Claim 10.
The motor of the present invention is characterized in that the integrated magnet body according to claim 10 is incorporated as described in claim 11.

  ADVANTAGE OF THE INVENTION According to this invention, it can provide the simple manufacturing method of the integrated magnet body which has high dimensional accuracy and is excellent in corrosion resistance and adhesive strength.

The manufacturing method of the integrated magnet body formed by laminating and integrating the plurality of magnet pieces of the present invention,
Step (1): A cationic electrodeposition coating composition comprising a thermosetting resin composition comprising an epoxy resin having a sulfonium group and a propargyl group, wherein the minimum value of the complex viscosity η ^* in the thermosetting process is 10 Pa · s or more. The process of electrodeposition coating on the surface of the magnet piece,
Step (2): a step of temporarily drying the individual magnet pieces electrodeposited in step (1),
Step (3): A step of laminating the individual magnet pieces temporarily dried in Step (2),
Step (4): A step of heating the laminated body composed of a plurality of magnet pieces laminated in Step (3) to complete the thermosetting of the thermosetting resin, and bonding and integrating the magnet pieces,
It is characterized by including at least.
Hereinafter, the manufacturing method of the integrated magnet body formed by laminating and integrating a plurality of magnet pieces of the present invention will be described in the order of steps.

Step (1): Electrodeposition of cationic electrodeposition paint on the surface of each magnet piece Thermosetting of epoxy resin having sulfonium group and propargyl group contained in the cationic electrodeposition paint used in step (1) Examples of the resin composition include a resin having a skeleton of a phenol novolac type epoxy resin or a cresol novolac type epoxy resin described in JP-A No. 2002-275431, and has a number average molecular weight of 700 to 5000. And having a sulfonium group of 5 to 250 mmol and a propargyl group of 10 to 395 mmol per 100 g of the solid content of the resin composition, and a total content of the sulfonium group and the propargyl group of 400 mmol or less.

The minimum value of the complex viscosity η ^* in the thermosetting process of the cationic electrodeposition coating is 10 Pa · s or more. By using a paint having such a complex viscosity η ^* , the fluidity of the resin when the thermosetting resin is cured by heating in the step (4) can be suppressed as much as possible. Accordingly, since the positional deviation of the magnet pieces before and after curing is prevented, an integrated magnet body having high dimensional accuracy can be obtained. The minimum value of the complex viscosity η ^* is preferably 25 Pa · s or more, and more preferably 40 Pa · s or more. On the other hand, the upper limit of the complex viscosity η ^* does not need to be specified in particular as long as it flows in the process of curing the resin and is compatible to the extent that it exhibits adhesive strength between the individual test pieces. s. The complex viscosity η ^* can be measured, for example, according to the method described in JP-A-2004-27214. The complex viscosity η ^* in the thermosetting process of the cationic electrodeposition coating can be increased, for example, by adding cross-linked resin particles to the cationic electrodeposition coating as necessary. By adding cross-linked resin particles to the cationic electrodeposition paint, a strong mutual force is generated between the polymer component of the cationic electrodeposition paint and the cross-linked resin particles, resulting in the development of pseudo composition fluidity (thixotropic properties) of the paint. By making a contribution, it becomes possible to ensure a certain viscosity in the temperature range of the curing process of the thermosetting resin, and the complex viscosity η ^* is increased. As the cross-linked resin particles, a so-called emulsion method, which is well known to those skilled in the art, is to cross-link a polymerizable monomer in an aqueous medium while performing emulsion polymerization in the presence of an emulsifying resin and a polymerization initiator. And those obtained by the so-called NAD method in which a polymerizable monomer is crosslinked while copolymerizing in a mixed solution of an organic solvent and a dispersion-stable resin soluble in the organic solvent. For example, refer to Japanese Patent Application Laid-Open No. 2004-339251). The volume average particle diameter of the crosslinked resin particles is preferably 0.05 to 1 μm. If the volume average particle size is less than 0.05 μm, the effect of adding is not sufficiently exhibited, and as a result, there is a risk that variation in dimensional accuracy is likely to occur due to insufficient contribution to stabilization of dimensional accuracy. On the other hand, when the thickness exceeds 1 μm, the electrodeposition coating properties are adversely affected, and the deposition film thickness may be abnormal. In addition, what is necessary is just to set the addition amount of the crosslinked resin particle to a cationic electrodeposition coating material suitably from the range of 1-30 weight% with respect to the resin solid content in a coating material, for example.

Furthermore, by adding insulating particles to the cationic electrodeposition coating, the insulating properties of the resin coating can be increased, and the insulating particles function as a spacer between the magnet pieces and the coating film formed By stabilizing the dimensional accuracy, an integrated magnet body with better dimensional accuracy can be obtained. Further, the complex viscosity η ^* in the thermosetting process of the cationic electrodeposition paint can be increased. Examples of the insulating particles include those having heat resistance such as alumina particles, silica particles, and glass beads that do not react with other components in the paint. The insulating particles are spherical and preferably have a D10% diameter of 5 μm or more and a D90% diameter of 100 μm or less, more preferably a D10% diameter of 15 μm or more and a D90% diameter of 60 μm or less. If the D10% diameter is less than 5 μm, it may not function sufficiently as a spacer. On the other hand, if the D90% diameter exceeds 100 μm, the resin film to be formed has a thickness of 10 to 50 μm. After temporary drying, a large number of particles larger than the thickness of the coating film will be present in the coating film, which may adversely affect the adhesiveness when the magnet pieces are bonded together in the step (4). The addition amount of the insulating particles to the cationic electrodeposition coating is desirably 1 to 30% by volume. If the addition amount is less than 1% by volume, the effect of addition may not be obtained. On the other hand, if it exceeds 30% by volume, the fluidity of the paint may be significantly lowered and the handleability may be deteriorated.

  Electrodeposition coating of the surface of each magnet piece of the cationic electrodeposition paint is performed using the cationic electrodeposition paint as a bath liquid (preferably 5 to 30% by weight of solid content) and the magnet piece as the object to be coated as a cathode. For example, a voltage of 50 to 450 V may be applied between the anode and the anode. The temperature of the bath liquid composed of the cationic electrodeposition paint is preferably 10 to 45 ° C.

  Before performing electrodeposition coating using a cationic electrodeposition paint, the surface of the magnet piece is subjected to chemical conversion treatment such as zinc phosphate treatment, or a lower layer coating such as a metal coating is formed. You may give corrosion resistance to a piece previously.

Step (2): Step of temporarily drying individual magnet pieces electrodeposited in step (1) Temporary drying in step (2) means removing moisture from the coating film formed on the surface of the magnet piece. It means drying to a state without stickiness or viscosity (tack free). The temporary drying is desirably performed at 40 to 120 ° C. If the temporary drying temperature is less than 40 ° C., the productivity may be deteriorated because it takes a long time to remove moisture in the coating film, whereas if it exceeds 120 ° C., curing of the coating film proceeds. In the step (4), there is a possibility that it is difficult to stack and integrate the magnet pieces using the adhesiveness of the thermosetting resin that has not been completely cured. In addition, the water | moisture content in a coating film can fully be removed by performing temporary drying normally for 3 to 120 minutes.

Step (3): Step of laminating the individual magnet pieces temporarily dried in step (2) What is necessary is just to carry out according to the standard using a predetermined number of magnet pieces.

Step (4): Step of completing the thermosetting of the thermosetting resin and bonding and integrating the magnet pieces. The heating for completing the thermosetting of the thermosetting resin in the step (4) is performed at 130 to 250 ° C. It is desirable to do. When the heating temperature is less than 130 ° C., it may take a long time to complete the thermosetting of the thermosetting resin, and the productivity may deteriorate. On the other hand, when the heating temperature exceeds 250 ° C., the thermosetting resin deteriorates. As a result, the characteristics may be impaired. The heating time is usually 5 to 240 minutes. Moreover, when heating, the integrated magnet body which has the more outstanding dimensional accuracy can be obtained by pressing a laminated body so that a pressure may be applied to the adhesion surfaces of a magnet piece. In order to sufficiently exert the effect of pressurization, the pressure is desirably 0.05 MPa or more. The upper limit of the pressure is not particularly specified as long as it is in a practically no problem range, but is usually 2.0 MPa.

  The integrated magnet body of the present invention obtained by the above steps has high dimensional accuracy, and is excellent in corrosion resistance and adhesive strength. For example, it can be incorporated into an IPM by the method shown in FIG. That is, the IPM 1 is composed of a core 2 and a rotor 3 disposed inside thereof, and the integrated magnet body 5 of the present invention is inserted as a rotor magnet into slots 4 provided at six locations of the rotor 3. Become. The IPM obtained in this way has a high motor efficiency.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention in detail, this invention is limited to the following description and is not interpreted. In the following examples and comparative examples, as described in U.S. Pat. No. 4,770,723 and U.S. Pat. No. 4,792,368, a known cast ingot is pulverized, and after pulverization, molding, sintering, and heat treatment are performed. Using a Nd-Fe-B sintered permanent magnet having a composition of 17Nd-1Pr-75Fe-7B (at%), 18 mm long x 15 mm wide x 4 mm thick obtained as a magnet piece It was.

Example 1:
Process (1)
(A) Preparation of thermosetting resin composition comprising epoxy resin having sulfonium group and propargyl group Epototo YDCN-701 having an epoxy equivalent of 200.4 (cresol novolak type epoxy resin manufactured by Tohto Kasei Co., Ltd.) 23.6 parts by weight of propargyl alcohol and 0.3 part by weight of dimethylbenzylamine are added to a separable flask equipped with a stirrer, thermometer, nitrogen inlet tube and reflux condenser, heated to 105 ° C. and reacted for 3 hours. A resin composition containing a propargyl group having an epoxy equivalent of 1580 was obtained. To this, 2.5 parts by weight of copper acetylacetonate was added and reacted at 90 ° C. for 1.5 hours. It was confirmed by proton (1H) NMR that some of the hydrogen atoms at the end of the added propargyl group had disappeared (containing 14 mmol / 100 g of resin solid content corresponding to acetylated propargyl group). Into this, 10.6 parts by weight of 1- (2-hydroxyethylthio) -2,3-propanediol, 4.7 parts by weight of glacial acetic acid and 7.0 parts by weight of deionized water were added and kept at 75 ° C. After reacting for 6 hours and confirming that the residual acid value was 5 or less, 43.8 parts by weight of deionized water was added to obtain the desired resin composition solution. The solid content of this product was 70.0% by weight, and the sulfonium value was 28.0 mmol / 100 g varnish. The number average molecular weight (polystyrene equivalent GPC) was 2443.

(A) Preparation of crosslinked resin particles 120 parts of butyl cellosolve was placed in a reaction vessel and stirred at 120 ° C. A solution prepared by mixing 2 parts of t-butylperoxy-2-ethylhexanoate and 10 parts of butyl cellosolve, 15 parts of glycidyl methacrylate, 50 parts of 2-ethylhexyl methacrylate, 40 parts of 2-hydroxyethyl methacrylate and n- A monomer mixture consisting of 15 parts of butyl methacrylate and having a solubility parameter of 10.1 was added dropwise over 3 hours. After aging for 30 minutes, a solution in which 0.5 part of t-butylperoxy-2-ethylhexanoate and 5 parts of butyl cellosolve were added dropwise over 30 minutes, and after aging for 2 hours, the mixture was cooled. The acrylic resin having an ammonium group had a number average molecular weight of 12,000 and a weight average molecular weight of 28,000 as measured by GPC. Quaternization was performed by adding 7 parts of N, N-dimethylaminoethanol and 15 parts of 50% aqueous lactic acid solution and stirring with heating at 80 ° C. When the acid value became 1 or less and the increase in viscosity stopped, heating was stopped to obtain an acrylic resin solution having an ammonium group with a nonvolatile content of 30%. The number of ammonium groups per molecule of the acrylic resin having ammonium groups was 6.0.
To the reaction vessel, 20 parts of the acrylic resin solution having an ammonium group obtained as described above and 270 parts of deionized water were added, and the mixture was heated and stirred at 75 ° C. To this, 1.5 parts of 2,2′-azobis (2- (2-imidazolin-2-yl) propane) 1.5% acetic acid neutralized aqueous solution was added dropwise over 5 minutes. After aging for 5 minutes, 30 parts of methyl methacrylate was added dropwise over 5 minutes. After further aging for 5 minutes, 170 parts of methyl methacrylate, 40 parts of styrene, 30 parts of n-butyl methacrylate, 5 parts of glycidyl methacrylate were added to a solution obtained by mixing 70 parts of an acrylic resin solution having an ammonium group and 250 parts of deionized water. A pre-emulsion obtained by adding and stirring an α, β-ethylenically unsaturated monomer mixture consisting of 30 parts of neopentyl glycol dimethacrylate was added dropwise over 40 minutes. After aging for 60 minutes, the mixture was cooled to obtain an aqueous dispersion of crosslinked resin particles. The aqueous dispersion of the obtained crosslinked resin particles had a nonvolatile content of 35%, a pH of 5.0, and a volume average particle size of 100 nm.

(C) Preparation of cationic electrodeposition paint 157.1 parts of deionized water was added to 142.9 parts of the thermosetting resin composition obtained in (a), and the ratio of the crosslinked resin particles to the resin solid content in the paint was Add an aqueous dispersion of the crosslinked resin particles obtained in (a) so as to be 4.0% by mass, and after stirring for 1 hour with a high-speed rotary mixer, prepare an aqueous solution so that the solid content concentration is 15% by weight. Got in.

(D) Electrodeposition coating The cationic electrodeposition paint obtained in (c) is transferred to a stainless steel container to form an electrodeposition bath (bath temperature: 30 ° C.). As a pretreatment, Surfdyne SD-5000 manufactured by Nippon Paint Co., Ltd. is used here. The thickness of the coating film after the temporary drying in step (2) is about 100 mm while applying the voltage of 100 V and stirring the paint so that the magnet piece subjected to the zinc phosphate treatment on the surface becomes the cathode. It was performed to be 30 μm.

Step (2):
After electrodeposition coating, with the magnet piece pulled up from the electrodeposition bath raised on the liquid surface, it is air-dried for 30 seconds, washed with water, temporarily dried at 100 ° C. for 25 minutes, and a tack-free coating film is formed. A magnet piece was obtained.

Step (3):
The three magnet pieces temporarily dried in the step (2) were laminated so that the surfaces of 15 mm × 4 mm were in contact with each other.

Step (4):
The laminate consisting of the three magnet pieces obtained in the step (3) is heated at 190 ° C. for 90 minutes while being pressurized at 0.2 MPa using a jig attached with a Teflon (registered trademark) tape, The thermosetting of the thermosetting resin was completed, and the magnet pieces were bonded together to obtain an integrated magnet body (the thickness of the resin coating was about 30 μm).

Example 2:
To the cationic electrodeposition paint obtained in step (1) of Example 1 (c), spherical alumina fine particles (AX-118; D10% diameter = 10 μm, D50% diameter = 17 μm, D90%) manufactured by Micron as insulating particles. (Diameter = 24 μm) was added in an amount corresponding to 3% by volume to obtain a spherical alumina fine particle dispersed cationic electrodeposition coating. Using this spherical alumina fine particle dispersed cationic electrodeposition coating, an integrated magnet body was obtained in the same manner as in Example 1.

Example 3:
157.1 parts of deionized water is added to 142.9 parts of the thermosetting resin composition obtained in (a) of step (1) of Example 1, and the ratio of the crosslinked resin particles to the resin solid content in the paint is The aqueous dispersion of the crosslinked resin particles obtained in step (1) (a) of Example 1 was added so as to be 20% by mass, and after stirring for 1 hour with a high-speed rotary mixer, the solid content concentration became 15% by weight. Thus, a cationic electrodeposition coating was obtained by preparing an aqueous solution as described above, and spherical glass beads (UB-01L; D10% diameter = 17 μm, D50% diameter = 27 μm, D90% diameter = made by Union Co., Ltd.) were used as insulating particles. 35 μm) was added in an amount corresponding to 10% by volume to obtain a spherical glass bead-dispersed cationic electrodeposition paint. Using this spherical glass bead-dispersed cationic electrodeposition paint, an integrated magnet body was obtained in the same manner as in Example 1.

Example 4:
15 volumes of spherical silica fine particles (FB-40S; D10% diameter = 18 μm, D50% diameter = 40 μm, D90% diameter = 73 μm) manufactured by Denki Kagaku Kogyo Co., Ltd. as insulating particles were added to the cationic electrodeposition paint obtained in Example 3. % Equivalent amount was added to obtain a spherical silica fine particle dispersed cationic electrodeposition coating. Using this spherical silica fine particle dispersed cationic electrodeposition coating, an integrated magnet body was obtained in the same manner as in Example 1.

Comparative Example 1:
5% by volume of spherical glass beads made by Union Co., Ltd. used in Example 3 as insulating particles were added to a blocked isocyanate curable cationic electrodeposition paint (Power Top U-600M) based on amino-modified epoxy resin made by Nippon Paint. A considerable amount was added to obtain a spherical glass bead-dispersed cationic electrodeposition coating. Using this spherical glass bead-dispersed cationic electrodeposition paint, an integrated magnet body was obtained in the same manner as in Example 1.

(Performance evaluation)
Performance evaluation of dimensional accuracy, corrosion resistance, and adhesive strength of the integrated magnet bodies obtained in Examples 1 to 4 and Comparative Example 1 was performed according to the following methods. The evaluation results are shown in Table 1 together with the minimum value of the complex viscosity η ^* in the thermosetting process of the cationic electrodeposition paint used for each production (measurement method is as follows).
(A) Dimensional accuracy When the positional deviation of the magnet pieces before and after the curing of the thermosetting resin in the step (4) is less than 0.5 mm, it was evaluated as ◯, and when it was 0.5 mm or more, it was rated as x.
(A) Corrosion resistance A salt spray test in which a 5% NaCl aqueous solution at 35 ° C. was sprayed for 48 hours was conducted.
(C) Adhesive strength It was evaluated as ◯ if it had an adhesive strength of 5 MPa or more in a compression shear test at 30 ° C. and 150 ° C. at 2 mm / min, and × if it did not.
(D) Complex viscosity Measured according to the method described in JP-A-2004-27214. Specifically, using a viscoelasticity measuring device (UBM Co., Ltd .: Rhesol-G3000), the heating rate is 3 ° C./min, and the measurement end temperature is 190 ° C. which is the heating temperature of the thermosetting resin in step (4). And using a parallel plate with a diameter of 18 mm, the distance between the plates at the time of viscosity measurement was 0.41 mm, and the frequency was 1 Hz.

As is clear from Table 1, it was found that the integrated magnet bodies of Examples 1 to 4 had high dimensional accuracy and were excellent in corrosion resistance and adhesive strength (each insulation was confirmed separately). . The integrated magnet bodies of Examples 1 to 4 have high dimensional accuracy because the minimum value of the complex viscosity η ^* in the thermal curing process of the used cationic electrodeposition coating is 10 Pa · s or more. The stability of dimensional accuracy is ensured by suppressing the fluidity of the resin when the thermosetting resin is cured by heating, and epoxy resin and crosslinked resin particles having sulfonium groups and propargyl groups It was thought that the strong mutual force between the two contributed to the expression of thixotropy.

Example 5:
An IPM was manufactured using the integrated magnet body of Example 3 by the method shown in FIG. This IPM had high motor efficiency.

  The present invention has industrial applicability in that it can provide a simple manufacturing method of an integrated magnet body having high dimensional accuracy and excellent corrosion resistance and adhesive strength.

It is explanatory drawing which shows the structural example of IPM.

Explanation of symbols

1 IPM
2 Core 3 Rotor 4 Slot 5 Integrated magnet body (Magnet for rotor)

Claims (11)

A method for producing an integrated magnet body formed by laminating and integrating a plurality of magnet pieces,
Step (1): A thermosetting resin composition comprising an epoxy resin having a sulfonium group and a propargyl group is included, and the minimum value of the complex viscosity η ^* in the thermosetting process is 10 Pa · s or more and the upper limit is 500 Pa · s . A process of electrodeposition coating a certain cationic electrodeposition paint on the surface of each magnet piece,
Step (2): a step of temporarily drying the individual magnet pieces electrodeposited in step (1),
Step (3): A step of laminating the individual magnet pieces temporarily dried in Step (2),
Step (4): A step of heating the laminated body composed of a plurality of magnet pieces laminated in Step (3) to complete the thermosetting of the thermosetting resin, and bonding and integrating the magnet pieces,
The manufacturing method characterized by including at least.   The manufacturing method according to claim 1, wherein temporary drying in the step (2) is performed at 40 to 120 ° C.   The method according to claim 1 or 2, wherein the heating in the step (4) is performed at 130 to 250 ° C.   4. The production method according to claim 1, wherein the cationic electrodeposition paint further contains crosslinked resin particles.   5. The production method according to claim 4, wherein the content of the crosslinked resin particles is 1 to 30% by weight based on the resin solid content in the paint.   6. The production method according to claim 1, wherein the cationic electrodeposition coating further contains insulating particles.   The manufacturing method according to claim 6, wherein the insulating particles are at least one selected from alumina particles, silica particles, and glass beads.   The manufacturing method according to claim 6 or 7, wherein the insulating particles are spherical with a D10% diameter of 5 µm or more and a D90% diameter of 100 µm or less.   The method according to any one of claims 6 to 8, wherein the content of insulating particles in the cationic electrodeposition coating is 1 to 30% by volume.   An integrated magnet body manufactured by the manufacturing method according to claim 1.   A motor comprising the integrated magnet body according to claim 10 incorporated therein.

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