Electromagnetic steel sheet adhesive coating composition, electromagnetic steel sheet laminate, and method for producing the same

Abstract

The present invention provides an electromagnetic steel sheet laminate having a fusion layer that can bond (fasten) electromagnetic steel sheets without using existing fastening methods such as welding, clamping, or interlocking, and a method for manufacturing the same. [Solution] The adhesive resin and the bonding additive are polyurethane, and the bonding additive includes a coupling agent containing aminosilane, and the aminosilane contained in the coupling agent is represented by the following chemical formula 1: [Formula 1] TIFF2023554120000020.tif60128

Description

Technical Field

[0001] The present invention relates to an electromagnetic steel sheet adhesive coating composition, an electromagnetic steel sheet laminate, and a method for manufacturing the same, and more particularly, to an electromagnetic steel sheet adhesive coating composition containing a urethane resin, an electromagnetic steel sheet laminate, and a method for manufacturing the same.

Background Art

[0002] Non-oriented electromagnetic steel sheets are steel sheets with uniform magnetic properties in all directions on the rolled sheet, and are widely used in cores of motors, generators, electric motors, small transformers, etc. Electromagnetic steel sheets are classified into two forms: those that must undergo stress relief annealing (SRA) after punching to improve magnetic properties, and those that omit stress relief annealing when the cost loss due to heat treatment is greater than the magnetic property effect due to stress relief annealing. The insulating film is a film coated in the finishing manufacturing process of laminates such as cores of motors, generators, electric motors, small transformers, etc., and usually requires electrical properties to suppress the generation of eddy currents. In addition, continuous punching processability, anti-adhesion property, and surface adhesion property are also required. The continuous punching processability means the ability to suppress the wear of the die when punching into a predetermined shape and then laminating a large number to form a core. The anti-adhesion property means the ability not to adhere between the core steel sheets after the stress relief annealing process of removing the processing stress of the steel sheet and restoring the magnetic properties. In addition to such basic properties, excellent coating workability of the coating solution and solution stability that can be used for a long time after blending are also required. Such an insulating film can be manufactured into an electromagnetic steel sheet laminate only by using a separate fastening method such as welding, clamping, and interlocking.

Summary of the Invention

Problems to be Solved by the Invention

[0003] An object of the present invention is to provide an electromagnetic steel sheet laminate having a fusion layer capable of bonding (fastening) electromagnetic steel sheets without using existing fastening methods such as welding, clamping, and interlocking, and a method for manufacturing the same. Specifically, it is to provide an electromagnetic steel sheet adhesive coating composition in which the components of the fusion layer formed between electromagnetic steel sheets are controlled to improve the adhesive force between electromagnetic steel sheets.

Means for Solving the Problems

[0004] The bonding composition for electromagnetic steel sheets of the present invention contains an adhesive resin and a bonding additive. The adhesive resin is polyurethane, and the bonding additive contains a coupling agent containing less than 5% by weight (excluding 0% by weight) of aminosilane. The aminosilane contained in the coupling agent is represented by the following Chemical Formula 1.

Chem.

[0005] The aminosilane contained in the coupling agent is represented by the following Chemical Formula 2.

Chem.

[0006] The bonding additive further contains one or more selected from the group consisting of a wetting agent, a curing agent, and a curing catalyst. The polyurethane is formed by the reaction of an isocyanate monomer and a polyol, and the isocyanate monomer is one or more selected from the group consisting of an aromatic isocyanate monomer and an aliphatic isocyanate monomer.

[0007] The aromatic isocyanate monomer is a monomer of Chemical Formula 3, Chemical Formula 4, or a combination thereof.

Chemical Formula

[0008]

Chemical Formula

[0009] In Chemical Formula 3, R 1 ~R 10 are, independently of one another, hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C5-C20 heteroaryl group, or an isocyanate group; one of R 1 ~R 5 is an isocyanate; one of R 6 ~R 10 is an isocyanate; R 3 and R8 When it is simultaneously an isocyanate, it is excluded. L is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group. n is any integer from 1 to 10. In the chemical formula 4, R 11 ~R 16 are, independently of each other, hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, or a substituted or unsubstituted C5-C20 heteroaryl group, an isocyanate group, or a substituted or unsubstituted C1-C10 alkyl isocyanate group. At least two of R 11 ~R 16 are isocyanate or a substituted or unsubstituted C1-C10 alkyl isocyanate.

[0010] The aliphatic diisocyanate monomer is a monomer represented by Chemical Formula 5.

Chemical formula

[0011] A laminate of the present invention includes a plurality of electromagnetic steel sheets and a fusion layer located between the plurality of electromagnetic steel sheets. The fusion layer includes an adhesive resin and a bonding additive. The adhesive resin is polyurethane, and the bonding additive includes a coupling agent containing aminosilane in an amount of less than 5% by weight (excluding 0% by weight).

Advantages of the Invention

[0012] According to the present invention, the components of the fusion layer formed between electromagnetic steel sheets can be controlled to improve the adhesion between the electromagnetic steel sheets. In addition, the electromagnetic steel sheets can be adhered without using existing fastening methods such as welding, clamping, and interlocking. Furthermore, an electromagnetic steel sheet adhesive coating composition excellent in all of film adhesion, peel characteristics, and ATF resistance characteristics can be provided.

Embodiments for Carrying Out the Invention

[0013] Terms such as first, second, and third are used to describe various parts, components, regions, layers, and / or sections, but are not limited thereto. These terms are used only to distinguish one part, component, region, layer, or section from another part, component, region, layer, or section. Thus, the first part, component, region, layer, or section described below may be referred to as the second part, component, region, layer, or section without departing from the scope of the present invention. The technical terms used herein are merely for referring to specific embodiments and are not intended to limit the present invention. The singular forms used herein include the plural forms as well, unless the context clearly indicates the contrary. The meaning of "including" used in the specification does not exclude the presence or addition of other characteristics, regions, integers, steps, operations, elements, and / or components while specifying a particular characteristic, region, integer, step, operation, element, and / or component.

[0014] When a part is referred to as being "on" another part, this means that it is directly on the other part or there are other parts therebetween. In contrast, when a part is referred to as being "directly on" another part, there are no other parts intervening therebetween. Unless otherwise defined, all terms including technical and scientific terms used herein shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Generally, terms defined in commonly used dictionaries shall be further construed to have meanings consistent with the relevant technical literature and the content currently disclosed, and shall not be construed in an ideal or overly formal sense unless otherwise defined.

[0015] As used herein, unless otherwise defined, "substituted" means that at least one hydrogen in a compound is substituted with a C1-C30 alkyl group; a C1-C10 alkoxy group; a silane group; an alkylsilane group; an alkoxysilane group; or an ethyleneoxyl group. As used herein, unless otherwise defined, "hetero" means an atom selected from the group consisting of N, O, S, and P. The alkyl group may be a C1-C20 alkyl group, and specifically, may be a C1-C6 lower alkyl group, a C7-C10 middle alkyl group, or a C11-C20 higher alkyl group.

[0016] For example, a C1-C4 alkyl group means one having 1 to 4 carbon atoms in the alkyl chain, which is selected from the group consisting of methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, and t-butyl. Typical alkyl groups include methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, etc.

[0017] Hereinafter, with reference to the accompanying drawings, embodiments of the present invention will be described in detail so that those of ordinary skill in the art to which the present invention belongs can easily implement them. However, the present invention can be realized in various different forms and is not limited to the embodiments described herein. The present invention aims to provide a bonding composition for electromagnetic steel sheets. The adhesive coating composition described in the present invention is also a term used to indicate the bonding composition. Further, the bonding composition of the present invention is a composition capable of bonding the surfaces of two or more steel sheets, and its use is not particularly limited. For example, it may be a self-bonding composition for electromagnetic steel sheets for providing self-bonding of electromagnetic steel sheets. The bonding composition for electromagnetic steel sheets of the present disclosure includes an adhesive resin and a bonding additive. The adhesive resin is polyurethane, and the bonding additive can include a coupling agent containing an aminosilane.

[0018] The aminosilane contained in the coupling agent is represented by the following Chemical Formula 1.

Chemical formula

[0019] The aminosilane contained in the coupling agent is represented by the following Chemical Formula 2.

Chemical formula

[0020] Specifically, the aminosilane may be 3-aminopropyl trimethoxysilane. The aminosilane is contained in an amount of less than 5% by weight (excluding 0% by weight) based on the total weight of the adhesive resin. Specifically, the aminosilane is contained in an amount exceeding 0.01% by weight based on the total weight of the polymer resin. More specifically, the aminosilane is contained in an amount of 0.05 to 3.0% by weight or 0.5 to 3.0% by weight based on the total weight of the adhesive resin. When the aminosilane is not added or is added in an excessively small amount, the effect of improving the adhesion at the interface between the base iron and the bonding layer cannot be expected, and there may be problems of poor peel adhesion and ATF resistance characteristics. On the other hand, when the aminosilane is added in an excessively large amount, agglomeration occurs in the bonding layer, deteriorating mechanical properties such as tensile strength and elongation, and there may be a problem that the adhesion between the base iron and the bonding layer is not improved. Therefore, preferably, the content of the aminosilane in the bonding composition for an electromagnetic steel sheet is controlled within the above range.

[0021] The bonding composition may have an elongation at break of 300 to 600%. Specifically, the elongation at break may be 400 to 500%. When the aminosilane coupling agent is not added, added in an excessively small amount, or added in an excessively large amount, the elongation at break may be less than 300%. If the elongation at break is low, the adhesion between the base iron and the bonding layer is not improved, and powder may be generated from the adhesive layer during punching, causing die contamination. On the other hand, when the elongation at break is excessively large, there may be a problem that the bonding layer is not cut by the cutting machine together with the steel plate during the slitting operation and is stretched. The polyurethane, which is the adhesive resin, is formed by the reaction of an isocyanate monomer and a polyol, and the isocyanate monomer may be one or more selected from the group consisting of an aromatic isocyanate monomer and an aliphatic isocyanate monomer.

[0022] The aromatic diisocyanate monomer may be a monomer of the following Chemical Formula 3, Chemical Formula 4, or a combination thereof.

Chemical formula

[0023]

Chemical formula

[0024] In the chemical formula 4, R 11 ~R 16 are, independently of each other, hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, or a substituted or unsubstituted C5-C20 heteroaryl group, an isocyanate group, or a substituted or unsubstituted C1-C10 alkyl isocyanate group, R 11 ~R 16 At least two of them are isocyanate or a substituted or unsubstituted C1-C10 alkyl isocyanate. In the monomer represented by the chemical formula 3, any one of R 1 ~R 5 is isocyanate, and any one of R 6 ~R 10 is isocyanate, and the case where R 3 and R 8 are simultaneously isocyanate is excluded, and the case where R 1 and R 10 are simultaneously isocyanate is further excluded. In the monomer represented by the chemical formula 3, any one of R 1 ~R 5 is isocyanate, and any one of R 6 ~R 10 is isocyanate, and any one of R 1 ~R 5 and any one of R 6 ~R 10 being simultaneously isocyanate symmetrically about L can be further excluded. Specifically, the monomer represented by the chemical formula 3 may be represented by the following chemical formula 5.

[0025]

Chem.

[0026]

Chem.

[0027] The aliphatic isocyanate monomer may be the monomer represented by the following Chemical Formula 7.

Chem.

[0028] The polyol may be the polyol of Chemical Formula 8.

Chemical Formula

[0029] Specifically, as the wetting agent, a silicone-based wetting agent is included. As an example of a silicone-based wetting additive, it may be polyether-modified polydimethylsiloxane. The wetting agent is added to the bonding composition for electromagnetic steel sheets to strengthen the interfacial adhesion force between the electromagnetic steel sheet and the fusion layer. Specifically, as the curing agent, it can include aliphatic amine-based, aromatic amine-based, aminoamine-based, or imidazole-based ones. More specifically, a dicyandiamide-based curing agent is included. As the curing catalyst, an imidazole-based curing catalyst is included.

[0030] The bonding composition for electromagnetic steel sheets of the present disclosure can further include 0.50 to 2.50 parts by weight of a curing agent with respect to 100 parts by weight of the adhesive resin. Specifically, it can further include 0.90 to 1.10 parts by weight of the curing agent. The curing agent plays a role in adjusting the reactivity of the surface of the adhesive coating layer. When the amount of the curing agent contained is excessively small, the curing reaction of the fusion layer may decrease, and there may occur a problem of poor stickiness on the surface of the fusion layer. Conversely, when the amount of the curing agent added is excessively large, the fastening force may decrease after low-temperature fusion. With respect to 100 parts by weight of the adhesive resin, 0.05 to 0.50 parts by weight of a wetting agent can be further included. Specifically, 0.09 to 0.11 parts by weight of the wetting agent can be further included. With respect to 100 parts by weight of the adhesive resin, 0.10 to 1.00 parts by weight of a curing catalyst can be further included. Specifically, 0.40 to 0.60 parts by weight of the curing catalyst can be further included. The polyurethane resin may have a number average molecular weight of 3,000 to 20,000 g / mol.

[0031] The electromagnetic steel sheet of the present disclosure includes an electromagnetic steel sheet substrate and a bonding coating layer located on the electromagnetic steel sheet substrate. The bonding coating layer includes an adhesive resin and a bonding additive. The adhesive resin is polyurethane, and the bonding additive can include a coupling agent containing an aminosilane.

[0032] The laminate of the present disclosure includes a plurality of electromagnetic steel sheets and a fusion layer located between the plurality of electromagnetic steel sheets. The fusion layer includes an adhesive resin and a bonding additive. The adhesive resin is polyurethane, and the bonding additive can include a coupling agent containing aminosilane. The thickness of the fusion layer of the electromagnetic steel sheet laminate may be 0.1 to 10 μm. If the thickness of the fusion layer is excessively thin, the adhesive strength will rapidly decrease. If it is excessively thick, problems due to stickiness may occur after coating winding. More specifically, the thickness of the fusion layer may be 5 to 7 μm. Coupling agents, wetting agents, curing catalysts, curing agents, etc. can remain in the fusion layer of the electromagnetic steel sheet laminate.

[0033] The method for manufacturing the electromagnetic steel sheet laminate of the present invention can include the steps of applying an adhesive coating composition to one or both surfaces of an electromagnetic steel sheet and then curing it to form an adhesive coating layer, and laminating a plurality of electromagnetic steel sheets on which the adhesive coating layer is formed and thermally fusing them to form a fusion layer.

[0034] Hereinafter, it will be specifically described for each step. First, prepare an adhesive coating composition. Since the adhesive coating composition has been described above, duplicate explanations will be omitted. Next, after coating the adhesive coating composition on the surface of the electromagnetic steel sheet, cure it to form an adhesive coating layer. This step is performed in a temperature range of 150 to 250 °C based on the plate temperature for curing the adhesive coating composition. Lay up a plurality of electromagnetic steel sheets on which the adhesive coating layer is formed and thermally fuse them to form a fusion layer 20. By the step of thermal fusion, the polymer components in the adhesive coating layer are thermally fused to form a fusion layer. The heat fusion stage can be carried out under a temperature of 150 - 250°C, a pressure of 0.05 - 5.0 Mpa, and a pressurization condition of 0.1 - 120 minutes. The above conditions can be satisfied independently, and two or more conditions can also be satisfied simultaneously. By adjusting the temperature, pressure, and time conditions in the heat fusion stage in this way, it is possible to achieve tight heat fusion between electromagnetic steel sheets without gaps or organic phases.

[0035] Hereinafter, preferred examples and comparative examples of the present invention will be described. However, the following examples are only preferred examples of the present invention, and the present invention is not limited to the following examples. Experimental Example Non-oriented electromagnetic steel sheets (50×50 mm, 0.35 mm t) were prepared as test pieces. An adhesive coating solution was applied to each prepared test piece with a bar coater and a roll coater to a certain thickness on the upper and lower parts, cured at a plate temperature of 150 - 200°C for 20 seconds, and then slowly cooled in the air to form an adhesive coating layer. Polyurethane was used as the polymer resin of the adhesive coating solution. For the polyurethane, 2,4’-MDI and HDI were mixed as diisocyanate monomers at a weight ratio of 6:4, and for the polyol, PPG (Poly(Propylene Glycol)) with a water molecular weight of 425 g / mol was used. The diisocyanate monomer was mixed at 40% by weight and the polyol at 60% by weight based on the total weight of the polymer resin. To the obtained polyurethane, 0.1 part by weight of a silicone-based wetting agent, 1 part by weight of a dicyandiamide-based curing agent, and 0.5 part by weight of an imidazole-based curing catalyst were mixed as additives per 100 parts by weight of the polyurethane polymer resin, and a coupling agent of the type shown in Table 1 below was mixed at the content shown in Table 1 to prepare an adhesive coating solution.

[0036] The glass transition temperature, tensile strength, and elongation rate, which are the physical properties of the manufactured adhesive coating solution, were measured and shown in Table 1. After stacking the electromagnetic steel sheets coated with the coating layer to a height of 20 mm, they were pressed with a force of 0.5 MPa and heat-sealed at 160 °C for 10 minutes. The thickness of the fusion layer after heat-sealing was about 3 μm. The heat-sealed fused bodies were evaluated according to the type of solution. As evaluation items, the peel adhesion force (T-peel, N / mm) and the ATF resistance property were evaluated and shown in Table 1 below.

[0037] The respective measurement methods are as follows. Maximum tensile strength and elongation: In order to measure the mechanical physical properties of the synthesized polyurethane polymer, it was poured onto release paper, coated to a uniform thickness using an applicator, and then dried in a vacuum oven at 100 °C for 24 hours to produce a dry film. The maximum tensile strength and elongation of the film were measured at a speed of 50 mm / min using a universal testing machine according to the ASTM D-1708 standard. Solution stability: After leaving the manufactured solution at a high temperature of 60 °C for 72 hours, changes due to precipitation and reaction were observed. The observation method was, first, to visually observe the color and non-uniformity of the solution with the naked eye, and second, to judge the presence or absence of surface defects due to coating.

[0038] Peel adhesion force (T-peel, N / mm): The specifications of the test piece for peel method (T-Peeloff) measurement were prepared based on ISO11339. After adhering two 25×200 mm test pieces with an area of 25×150 mm 2 and bending the unbonded part to 90 to produce a T-type tensile test piece. After fixing the test piece prepared by the peel method (T-Peeloff) to the upper and lower jigs (JIG) with a constant force, the tensile force of the laminated sample was measured using a device that measures while pulling at a constant speed. At this time, in the case of the shear method, the measured value was the point where the interface with the minimum adhesion force among the interfaces of the laminated sample dropped off. After maintaining the temperature of the test piece at 60 °C using a heating device, the adhesion force was measured.

[0039] ATF Resistance Property Evaluation Method: When using a drive motor in an automobile, heat is generated during rotation, and ATF is used to cool it. Therefore, in order to ensure the adhesion reliability during long-term use, it is important that the adhesive strength of the laminated coil is maintained while being impregnated with ATF. For this reason, the ATF resistance property was evaluated. After impregnating the manufactured laminated coil in ATF at a temperature of 150 °C for 500 hours, the shear adhesive strength was tested. The shear adhesive strength for measuring the ATF resistance property was measured by the shear method. The specifications of the test pieces for shear method measurement were prepared based on ISO4587. Two test pieces of 25×100 mm were adhered at an area of 12.5×25 mm 2 and heat-sealed under the above conditions to prepare a test piece by the shear method. After fixing the test piece prepared by the shear method to the upper and lower jigs (JIG) with a constant force, it was measured using a device that measures the tensile force of the laminated sample while pulling at a constant speed. At this time, in the case of the shear method, the measured value was the point where the interface with the minimum adhesive strength among the interfaces of the laminated sample fell off.

[0040]

Table 1

[0041] As can be seen from the results in Table 1 above, when using an alkoxysilane coupling agent, it was confirmed that even if the types were different, the peel characteristics (T-peel characteristics) were inferior. It was also confirmed that Comparative Example 1, even when using the same type of aminosilane coupling agent as in the examples but with an excessive content, was inferior in peel characteristics. When not using aminosilane or using a small amount as in Comparative Examples 5 and 6, it was found that not only were the peel characteristics (T-peel characteristics) and ATF resistance properties slightly inferior to those of the examples, but also the elongation rate was low and it was not suitable for the punching operation for subsequent laminate manufacturing.

[0042] The present invention is not limited to the above-described embodiments and can be manufactured in various different forms. Those having ordinary knowledge in the technical field to which the present invention pertains will understand that it can be implemented in other specific forms without changing the technical idea or essential features of the present invention. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Claims

1. Comprising an adhesive resin and a bonding additive, wherein the adhesive resin is polyurethane, the bonding additive comprises a coupling agent containing 0.05 to 3.0% by weight of aminosilane with respect to the polyurethane, the polyurethane is formed by the reaction of an isocyanate monomer and a polyol, and the isocyanate monomer consists of an aromatic isocyanate monomer and an aliphatic isocyanate monomer, the aminosilane contained in the coupling agent is represented by the following Chemical Formula 2, the aromatic isocyanate monomer is a monomer represented by the following Chemical Formula 3, the aliphatic isocyanate monomer is a monomer represented by the following Chemical Formula 5, characterized in that it is a bonding composition for an electromagnetic steel sheet. 【Chemical Formula 2】 Here, in the above Chemical Formula 2, R1 to R5 are each independently hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C5-C20 heteroaryl group, or an isocyanate group, L4 is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group, n is any integer from 1 to 10, 【Chemical Formula 3】 in the above Chemical Formula 3, R1 to R10 are each independently hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C5-C20 heteroaryl group, or an isocyanate group, any one of R1 to R5 is an isocyanate, and any one of R6 to R10 is an isocyanate, the case where R3 and R8 are simultaneously isocyanates is excluded, L is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group, n is any integer from 1 to 10, 【Chemical Formula 5】 in the above Chemical Formula 5, R is a substituted or unsubstituted C1-C10 alkyl group, or a substituted or unsubstituted C3-C12 cycloalkyl group.

2. The bonding composition for an electromagnetic steel sheet according to claim 1, wherein the bonding additive further contains one or more selected from the group consisting of a wetting agent, a curing agent, and a curing catalyst.

3. An electromagnetic steel sheet substrate, and a bonding coating layer located on the electromagnetic steel sheet substrate, wherein the bonding coating layer contains an adhesive resin and a bonding additive, the adhesive resin is polyurethane, the bonding additive contains a coupling agent containing 0.05 to 3.0% by weight of aminosilane with respect to the polyurethane, the polyurethane is formed by the reaction of an isocyanate monomer and a polyol, and the isocyanate monomer consists of an aromatic isocyanate monomer and an aliphatic isocyanate monomer, the aminosilane is represented by the following Chemical Formula 2, the aromatic isocyanate monomer is a monomer represented by the following Chemical Formula 3, and the aliphatic isocyanate monomer is a monomer represented by the following Chemical Formula 5. An electromagnetic steel sheet characterized by this. 【Chemical Formula 2】 Here, in the above Chemical Formula 2, R1 to R5 are each independently hydrogen, deuterium, a substituted or unsubstituted C1 - C10 alkyl group, a substituted or unsubstituted C6 - C20 aryl group, a substituted or unsubstituted C5 - C20 heteroaryl group, or an isocyanate group, L4 is a substituted or unsubstituted C1 - C10 alkylene group, a substituted or unsubstituted C2 - C10 alkynylene group, a substituted or unsubstituted C6 - C20 arylene group, or a substituted or unsubstituted C5 - C20 heteroarylene group, n is any integer from 1 to 10, 【Chemical Formula 3】 in the above Chemical Formula 3, R1 to R10 are each independently hydrogen, deuterium, a substituted or unsubstituted C1 - C10 alkyl group, a substituted or unsubstituted C6 - C20 aryl group, a substituted or unsubstituted C5 - C20 heteroaryl group, or an isocyanate group, any one of R1 to R5 is an isocyanate, and any one of R6 to R10 is an isocyanate, when R3 and R8 are simultaneously isocyanates, it is excluded. L is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group, n is any integer from 1 to 10, [Chemical Formula 5] In the chemical formula 5, R is a substituted or unsubstituted C1-C10 alkyl group or a substituted or unsubstituted C3-C12 cycloalkyl group.

4. A plurality of electromagnetic steel sheets, A fusion layer located between the plurality of electromagnetic steel sheets, The fusion layer includes an adhesive resin and a bonding additive, The adhesive resin is polyurethane, The bonding additive includes a coupling agent containing 0.05 to 3.0% by weight of aminosilane with respect to the polyurethane, The polyurethane is formed by the reaction of an isocyanate monomer and a polyol, and the isocyanate monomer consists of an aromatic isocyanate monomer and an aliphatic isocyanate monomer, The aminosilane is represented by the following chemical formula 2, The aromatic isocyanate monomer is a monomer represented by the following chemical formula 3, The aliphatic isocyanate monomer is a monomer represented by the following chemical formula 5, a laminate. 【Chemical 2】 Here, in the chemical formula 2, R1 to R5 are, independently of each other, hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C5-C20 heteroaryl group, or an isocyanate group, L4 is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group, n is any integer from 1 to 10, 【Chemical Formula 3】 In the chemical formula 3, R1 to R10 are, independently of each other, hydrogen, deuterium, a substituted or unsubstituted C1-C10 alkyl group, a substituted or unsubstituted C6-C20 aryl group, a substituted or unsubstituted C5-C20 heteroaryl group, or an isocyanate group, Any one of R1 to R5 is an isocyanate, and any one of R6 to R10 is an isocyanate, The case where R3 and R8 are simultaneously isocyanates is excluded, L is a substituted or unsubstituted C1-C10 alkylene group, a substituted or unsubstituted C2-C10 alkynylene group, a substituted or unsubstituted C6-C20 arylene group, or a substituted or unsubstituted C5-C20 heteroarylene group, n is any integer from 1 to 10, 【Chemical Formula 5】 in the chemical formula 5, R is a substituted or unsubstituted C1-C10 alkyl group, or a substituted or unsubstituted C3-C12 cycloalkyl group.

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