JP2721466B2 - Method for producing grain-oriented electrical steel sheet with extremely excellent coating and magnetic properties - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a grain-oriented electrical steel sheet having an excellent magnetic property by forming a uniform glass film when producing a grain-oriented electrical steel sheet.

[0002]

2. Description of the Related Art Oriented magnetic steel sheets are usually rolled by hot rolling a material containing 4% or less of Si, and then subjected to one or two or more cold rolling steps including intermediate annealing to obtain a final sheet thickness. Then N ₂
+ H ₂ or in an atmosphere of H ₂ or the like to control the P H ₂ O / P H ₂ perform decarburization annealing is performed to form the oxide film mainly decarburization and SiO _2. Thereafter, an annealing separator containing MgO as a main component is applied in the form of a slurry in a coating roll or the like, subjected to final finish annealing, secondary recrystallization, purification, glass coating formation, and, if necessary, insulation coating treatment and heat treatment. After flattening, the final product is obtained. Further, in the case of a high magnetic flux density grain-oriented electrical steel sheet, depending on the application, before or after the insulating film treatment, a magnetic domain refining treatment by applying a linear flaw using a laser, a press roll, a rolling roll, a tooth roll, a marking, etc. To improve iron loss.

[0003] This grain-oriented electrical steel sheet utilizes a phenomenon in which (110) <001> crystals having a <001> axis grow preferentially by high-temperature secondary recrystallization. In this secondary recrystallization process, the (110) plane having low surface energy grows preferentially, and the finely dispersed Al as an inhibitor in steel is finely dispersed.
It is considered that the (110) <001> crystal grows preferentially because it erodes other crystals whose growth is suppressed by N, MnS or the like. Therefore, in order to produce an excellent grain-oriented electrical steel sheet, it is important to control the dispersion of AlN, MnS, and the like in the steel, and to control the decomposition thereof.

The change in the inhibitor during the final annealing is affected by the oxide film on the steel sheet surface formed by decarburizing annealing, the annealing separator, the thermal cycle of finish annealing, and the atmospheric conditions. Among them, the properties of the annealing separator MgO and the effect of additives are particularly large. The annealing separator MgO reacts with the SiO ₂ -based oxide film formed by the decarburizing annealing to form a forsterite-based film usually called a glass film (2M).
gO + SiO ₂ → Mg ₂ SiO ₄ ). In the formation of the glass film, the properties of MgO, in particular, the particle size, purity, and activity, as well as the hydration amount, the amount of application, and the adhesion of the applied film when the steel sheet is applied are greatly affected. The type and amount of the additive added as, and the state of dispersion on the MgO surface and the state of dispersion on the surface of the steel sheet affect the timing, speed, amount and uniformity of the glass coating. This difference in the reaction during the glass film formation process causes additional oxidation of the steel sheet surface, intrusion of N in the annealing atmosphere gas, and conversely, reduction of N, S, etc. in the steel, and has a great effect on the inhibitor. Secondary recrystallization and, consequently, magnetic properties are also affected.

[0005] As described above, it is important to control the properties of the annealing separator and the coating state on the steel sheet surface with respect to the glass coating and the magnetic properties which are important in determining the commercial value of the grain-oriented electrical steel sheet. Has become an important development issue for those skilled in the production of grain-oriented electrical steel sheets.

[0006] MgO used as an annealing separating agent is generally prepared by preparing a raw material crystal having a mean particle size of several hundred angstroms to several μm from a raw material such as magnesium hydroxide, magnesium carbonate, or basic magnesium carbonate. 700
Baking at a temperature of about 1500 ° C. by a rotary kiln, a batch kiln, etc.
A 5.0 μm MgO crystal is obtained and used. The MgO thus obtained is usually mixed with various additives as a forsterite formation accelerator, suspended in water to form a slurry, and placed in a tank provided with a rotating blade such as a propeller-shape or a shear-blade-shape. After stirring, the mixture is applied to the surface of a steel plate with a rubber roll or the like and dried. At that time, the MgO particles and additives are aggregated by sintering at the time of sintering at the manufacturing stage or by agglomeration of particles due to moisture absorption at the time of storage from the sintering stage to the use stage or a strong agglutination reaction of the particles at the stage of suspending with water. At the stage of being applied to the steel sheet surface, it becomes coarse particles of several μm to several tens μm. This is a problem caused by particle surface defects in the stage of MgO production or distortion of the particle surface received in stages such as pulverization. Particularly, in order to obtain low hydrated MgO, a technique by high-temperature firing is essential, Agglomeration tendency in such a slurry is further strengthened.

[0007] In such a case, on the steel sheet surface after coating and drying, the contact area of MgO particles decreases, and the adhesion and uniformity of the coating film decrease. Further, in such a case, the viscosity of the slurry is reduced, so that the coating property in high-speed operation is deteriorated, and a uniform coating film cannot be obtained. As a result, the properties of the glass coating are deteriorated.

[0008] When an additive is used in combination with MgO,
As with MgO, the additive itself becomes coarse particles due to sintering at the time of production and agglomeration in the slurry, and is present unevenly on the coating film or the steel plate oxide film. This results in a uniform reaction, which causes a problem in obtaining a uniform glass coating, and, of course, may affect inhibitor control and magnetic properties.

As a means for solving such a problem due to a decrease in reactivity and a decrease in adhesion due to sintering and agglomeration of the annealing separator, conventionally, the physical properties of MgO are controlled at the production stage to suppress the agglomeration, There have been methods in which MgO itself has hydration properties to assist the formation of forsterite with water or to add an additive of a reaction accelerator more than necessary. Japanese Patent Application Laid-Open No. Sho 62-156226 has proposed a method of activating the outermost surface layer of MgO particles by the present inventors. In this method, Mg obtained by high-temperature firing is used.
The amount of hydration (M
g (OH) ₂ ), the uniformity of the glass film is improved, and the effect of improving the magnetic properties is obtained. In Japanese Patent Application Laid-Open No. Hei 2-26278, calcined MgO is
Treated in a steam-containing atmosphere of at least
The chemisorbed phase is converted to 0.8 based on MgO weight in terms of H ₂ O.
A method for obtaining a grain-oriented electrical steel sheet having a uniform glass coating and excellent magnetic properties by applying an annealing separator containing MgO formed to about 2.5% to a steel sheet after decarburization annealing and finish annealing. Is disclosed.

All of these techniques solve the problem of agglomeration of MgO particles during the application of an annealing separator by modifying the surface of MgO particles after firing by performing a special surface treatment at a high temperature to reduce the surface energy. Thus, the compatibility with water is improved, and at the same time, the forsterite forming reaction is improved by a certain amount of OH formed on the surface layer of the MgO particles. Due to this effect, the MgO particles are applied to the steel sheet surface in a state of better dispersion than before, and a considerable effect is obtained.

[0011] However, there are problems of sintering due to MgO production conditions, stability of the chemisorption phase, and agglomeration due to aging change from MgO production to use. Technology development is desired.

[0012]

SUMMARY OF THE INVENTION The present invention relates to a method for preparing a sintered body, agglomerate, and slurry produced during the production of MgO and additives when applying an annealing separator to the surface of a decarburized plate in the production of grain-oriented electrical steel sheets. The problem of agglomeration at the stage is to be improved by a novel slurry preparation method that has not been tried in the conventional grain-oriented electrical steel sheet manufacturing process, and in this case, inactive fine-grain MgO in which a trace element is adjusted as MgO is used. By using it, the amount of hydration is extremely suppressed, the reactivity is improved by the dispersing effect and the surface activating effect, and the viscosity of the slurry is adjusted to form a uniform high-quality glass coating by applying it evenly to the steel plate surface. Further, it is another object of the present invention to provide a grain-oriented electrical steel sheet having excellent magnetic properties.

[0013]

Means for Solving the Problems In the glass film forming step from the decarburizing annealing of the grain-oriented electrical steel sheet to the application of the annealing separating agent to the finish annealing step, the present inventors have considered that the annealing separating agent and the underlying oxide film are not used. The reactivity improvement technology was studied. In this study, the study focused on the uniform and ultrafine dispersion method of the annealing separator MgO and the additive and the properties of MgO.

As a method for preparing the slurry of the annealing separating agent, usually, pure water is charged into a cylindrical container, and MgO,
The additive is introduced, and the mixture is automatically stirred by a device provided with a rotating body in the form of a propeller, a plate, or a shearing blade, and is stirred as uniformly as possible.

When the slurry is dispersed by such a conventional stirring apparatus, a very high speed stirring and a long time stirring are required to perform the fine particle dispersion, and there is a limit to the fine particle dispersion. In particular, such a stirring technique cannot sufficiently obtain the effect of crushing the sintered body and the aggregate during the production of MgO and activating the surface of the particles.

Further, a major problem with such a method is that the slurry temperature rises due to friction between the particles in the slurry due to high-speed or long-time stirring or between the particles and the rotating body of the stirring device, and the hydrated water increases. . As a result, there arises a problem that the glass coating characteristics and the magnetic characteristics are deteriorated. Therefore, the present inventors have conducted a huge amount of experiments on a dispersion technique that can reliably disintegrate the sintered body and agglomerates of the annealing separator by a slurry dispersing process in a short time and do not increase the hydration moisture generated in the conventional technique. And conducted a study.

As a result, as a method of adjusting the annealing separator which can solve the above problem, a slurry in which the annealing separator is dispersed in water is used.
Suitable for a cylindrical container provided with a disk-shaped rotating body.
Using a bead mill filled with the amount of microparticle beads,
By crushing process the serial slurry was develop improved techniques activation of very efficient ultra atomization and particle surface. At this time, by controlling and applying the physical property values to a specific range at the stage of producing MgO, the sintered body of the annealing separator, coarsening of particles due to agglomerates and non-uniformity of components such as additives, In addition to solving problems such as non-uniformity, poor adhesion of the coating film and increase in hydration moisture, the glass film formation reaction improvement technology brought about by the MgO component was added to improve the glass film and the magnetic properties at the same time. It has been reached.

Hereinafter, the present invention will be described in detail based on experimental results. In this experiment, C: 0.065 by weight
%, Si: 3.15%, Mn: 0.060%, Sn:
0.06%, Cu: 0.06%, S: 0.024%, A
l: 0.027%, N: 0.0080%, high magnetic flux density grain-oriented electrical steel sheet slab consisting of balance Fe and unavoidable impurities is hot-rolled, annealed and cold-rolled by a known method to obtain a final sheet thickness of 0.1%.
29 mm. Then _{N 2 25% + H 2 75} %, the dew point 6
Decarburization annealing was performed at 850 ° C. × 150 seconds in an atmosphere of 5 ° C. Thereafter, as shown in Table 1, MgO1 having a CAA value of 80 seconds was used.
00 parts by weight, 5 parts by weight of TiO ₂ , Na ₂ B ₄ O ₇ 0.2
Parts by weight, an annealing separator consisting of 0.2 parts by weight of ZrCl ₂ was adjusted as a water slurry by changing the dispersion conditions, each was applied to the decarburized annealing plate, dried, and then subjected to final finishing annealing at 1200 ° C. × 20 hours. Was. Thereafter, 100 ml of 20% colloidal silica + 50 ml of 50% Al phosphate + 5 g of CrO ₃
Was applied and baked at 850 ° C. for 30 seconds to obtain a product. In this experiment, Table 2 shows the observation results of the application state of the annealing separating agent, the glass coating of the product, and the investigation results of the magnetic properties.

[0019]

[Table 1]

[0020]

[Table 2]

As a result of this experiment, the method using a bead mill or a bead mill and a grindstone mill as a slurry dispersing method is free from agglomeration or agglomeration of an annealing separating agent, and is uniform, fine and has good adhesion. Was applied. It was also confirmed from the results of measuring the particle size in the slurry that the particles according to the present invention were extremely fine.

The glass coatings after finish annealing were all uniform and had good adhesion, and high coating tensions were obtained according to the present invention. In addition, the magnetic properties were good, and particularly those having good iron loss properties were obtained. On the other hand, in the case of the slurry dispersion method using only a mixer using a rotating body with a shearing blade, the surface after the application of the annealing separator had many agglomerates and sinters due to a sintered body, and was an uneven coating film. The glass coating on the product plate was also thin, non-uniform, and the adhesion, coating tension, and magnetic properties were considerably inferior to those of the present invention.

Here, the contents of the processing will be briefly described. The dispersion treatment in the present invention is to separate aggregated particles generated before or after the preparation of the slurry or to prevent the aggregation reaction from occurring.On the other hand, crushing not only separates the MgO particles from each other, This refers to the grinding process for each sintered body or particle. As a method of performing these, there are mechanical means, physical means, and shock means as described later.

Next, the reasons for limitation of the present invention will be described. The most characteristic feature of the present invention is a method for preparing an annealing separator slurry. In the present invention, the method of disintegrating and dispersing the ultrafine particles of the slurry is basically performed by using an apparatus called agitator type bead mill in which bead-shaped particles are filled in a cylindrical container. Beads having a diameter of about several mm are used, and the number of rotations of the agitator disk is changed, the diameter of the beads, the filling rate of the beads, the material of the beads, the flow rate of the slurry, and the like are changed. The pulverization treatment of the present invention may be performed not only by this bead mill but also in combination with other mechanical and vibrational pulverization techniques.

As mechanical means, grinding using a rotating body such as a grindstone roll, a metal grinder roll, and a shear blade,
It is a stirring device. The impact means is one in which crushing and dispersion are performed by vibration stirring in a container containing a large-diameter ball having a diameter of several mm or more as in the bead type.

The combination of the bead mill with other crushing techniques improves the crushing efficiency, stability and equipment durability of other mechanical and vibratory dispersing techniques, while improving the durability of the equipment. This is performed in order to increase the durability, the processing capacity, and the like, and also has the effect of reducing the pulverization load in a bead mill.

The atomization and crushing treatment is performed by continuously, periodically or circulating these devices. The most preferable use is to install a bead mill immediately before the slurry circulation device in the continuous coating line and adjust the material, diameter, rotation speed of the agitator, clearance on the slurry outlet side, etc. as described above. Is good. In these treatments, the slurry temperature may increase and the hydration moisture may increase due to friction between the annealing separator material and the crushing tool, friction between particles, collision, and the like. It is better to carry out while continuously cooling the slurry or pulverizer.

In the slurry thus crushed and dispersed to form ultra-fine particles, MgO and additive substances are super-finely dispersed, and a new extremely thin hydrated layer is formed on the outermost layer of the particles. The treatment for forming the hydrated layer is the activation treatment of the particle surface. Thereby, the reactivity of the particles themselves is dramatically improved, the surface energy of the particles is reduced, and the particles are stabilized. Therefore, the slurry does not re-aggregate even if the slurry is stirred for a long time by the ordinary stirring process.

Next, the particle diameter by the pulverization treatment in the present invention is 10 μm or less in average particle diameter. Usually, since MgO for grain-oriented electrical steel sheets is fired at a high temperature, it has many sintered grains, and when mixed with water to form a slurry, agglomeration reaction occurs and coarse grains having an average grain size of 20 to 40 μm are formed. Become. Therefore, 1
The surface in which coarse particles of about 00 μm are mixed has a rough coating state, and the forsterite forming reaction of the oxide film on the steel sheet is reduced due to coarsening. The present inventors have conducted extensive research and experiments, and as a result, have found that if the particles can be pulverized to an average particle size of 10 μm or less, a remarkable effect of improving the film forming reaction can be obtained. If it exceeds 10 μm, the effect of improving the reactivity is not sufficient. On the other hand, if it is 10 μm or less, the effect of the film forming reaction is gradually improved, but if it is less than 1 μm, it becomes difficult to control the hydration moisture. The most preferable range of the particle size by the pulverization treatment is 7 to 1 μm.

Next, the viscosity of the slurry by the crushing / dispersion treatment of the present invention is 20 to 200 cP. The present invention increases the viscosity of the slurry due to the formation of a hydration layer on the surface and the ultra-fine atomization,
The applicability can be significantly improved. Mg used for annealing separator
As the O production conditions, inert MgO fired at a high temperature or MgO in which agglomeration is remarkably generated as in the case where a long time has passed after production.
Even when it is applied to, for example, its disintegration and dispersing effects improve coatability. However, when the usual coating roll method is changed, even if the viscosity becomes too high, the application operation becomes difficult, so there is a limitation.

If it is less than 20 cp, the coating property and liquid adhesion to the steel sheet surface are deteriorated, and coating unevenness due to the roll pattern or the movement of the liquid during drying tends to occur on the coating film, which is limited. Meanwhile, 2
If it is more than 00 cP, on the other hand, the viscosity is too high, so that uniform coating at high speed becomes difficult. In such a case, a method of changing the mixing ratio of water is also conceivable, but it is complicated to respond to the change as an actual work, and by selecting appropriate crushing and crushing conditions,
It is preferable to control the viscosity appropriately.

Next, MgO used in the present invention includes:
Cl: 0.01 to 0.05%, B: 0.01 to 0.15
%, Ca as CaO: 0.1 to 1.5%, S: 0.01
０．２0.2%, CAA value: 50 to 250 seconds (measured at 30 ° C.). Cl, B, and Ca all have an effect of promoting the formation of a glass film if they are in appropriate amounts, and the effect is further increased when the ultrafine graining and activation treatment technology of the present invention is applied. Below the above component range, the reactivity of MgO is not sufficient even by the technique of the present invention, and affects the glass coating and the magnetic properties.

On the other hand, if the amount is more than the above-mentioned components, a metallic luster spot peculiar to the peroxide phenomenon,
This produces scale and gas mark-like defects. S diffuses into the steel at the time of finish annealing to provide a reinforcing effect of the inhibitor MnS. S: If it is 0.01% or less, such an effect is hardly obtained, and if it is 0.40% or more, a good magnetic flux density cannot be obtained, so that it is limited.

The CAA value of MgO is 50 seconds to 250 seconds measured at 30 ° C. The micronization and activation treatment by the crushing / dispersion treatment of the present invention causes a slight increase in hydrated water. For this reason, when the CAA value is 50 seconds or less, this tendency is increased, and it is difficult to use the slurry in the optimum hydrated moisture region even if the slurry is cooled or the like. In the present invention, the effect of the formation of a hydrated layer on the surface and the effect of ultrafine atomization are extremely large, and it is advantageous to use low hydrated MgO. Therefore, it cannot be used under normal use conditions up to a CAA value of 250 seconds. It can be used up to various conditions. If the CAA value is 250 seconds or more, the crushing / dispersion technique of the present invention is limited because the reactivity cannot be improved and the viscosity cannot be sufficiently controlled.

Compounds to be optionally added to MgO of the present invention include Sb, Sr, Ti, Al, Mn, S
oxides, hydroxides of n, Zr, Ca, Mg, Na, K,
One or more selected from chlorides, sulfides, sulfates, and borates are added in an amount of 0.1 to 1 with respect to 100 parts by weight of MgO.
0 parts by weight. These compounds are composed of MgO and underlying SiO.
The formation reaction of forsterite generated by the reaction with the _two layers is reduced in temperature, and the glass coating is made uniform and high in tension.
In addition, the inhibitor Al
Increase the stability of N, MnS, etc. The optimum amount depends on the form of the compound. However, if the amount is less than 0.1 part by weight, such an effect cannot be obtained. If the amount is more than 10 parts by weight, film defects peculiar to the peroxidation phenomenon occur, or the film thickness of the film is excessively increased, thereby deteriorating the magnetism.

[0036]

EXAMPLES Example 1 C: 0.068%, Si: 3.25%, Mn:
0.058%, S: 0.025%, Al: 0.024
%, N: 0.0077%, Cu: 0.085%, Sn:
A high magnetic flux density directional electromagnetic steel sheet material containing 0.075% and the remainder Fe and unavoidable impurities was treated by a known method to a final sheet thickness of 0.225 mm. This steel sheet is N ₂ 25% + H
₂ 75%, 850 ℃ × 110 in an atmosphere of a dew point of 650 ° C.
After decarburizing annealing for 2 seconds, the CAA value was 100 as shown in Table 3.
Second, Cl: 0.030%, S: 0.150%, B: 0.
A slurry obtained by treating an annealing separator mainly composed of MgO of 120% and CaO: 0.7% under different stirring conditions was applied, dried, and then subjected to a final finish annealing at 1200 ° C. for 20 hours. Thereafter, 100 ml of 20% colloidal silica, 50 ml of 50% aluminum phosphate and 5 g of CrO ₃ were used as insulating coating agents.
Was applied and baked at 850 ° C. for 30 seconds to obtain a product. Table 4 shows the application state of the annealing separator and the product characteristics in this manufacturing process.

[0037]

[Table 3]

[0038]

[Table 4]

As a result of this experiment, in each of the samples according to the present invention, the annealing separator was finely and finely disintegrated and dispersed, and the viscosity of the slurry was appropriately improved. As a result, a uniform and fine coating film was obtained. In addition, the glass coating was uniformly improved, and good results were obtained with good magnetic properties. On the other hand, when the slurry was not adjusted according to the present invention, the coating film was non-uniform and the roughness was considered to be due to agglomerates. As a result, the glass coating and the magnetic properties were considerably inferior to those of the present invention.

[0040]

According to the present invention, a sintered product or an agglomerate is prepared by stirring an annealing separator slurry controlled to specific physical properties and components in a container filled with fine particle beads or by using another dispersing technique together. Is crushed, dispersed, and ultrafinely divided. Further, an extremely thin hydrated layer is formed on the surface of the particles of the annealing separator, and an effect of activating the surface is obtained. Thereby, a fine coating film can be uniformly formed on the surface of the decarburized plate. As a result, as shown in FIG. 1, the glass film forming reaction is accelerated at the time of finish annealing and the temperature is increased, and finally a uniform and high quality glass film is formed. In the course of this reaction, the effect of the annealing separator component has a synergistic effect, and the quality of the glass coating is further improved. The effect of promoting the film formation keeps the inhibitor in the steel stable and at the same time improves the magnetic properties.

[Brief description of the drawings]

FIG. 1 shows an investigation of the reaction of forming a glass film at the time of raising the temperature of finish annealing by preparing an annealing separator slurry by disintegrating a slurry using a bead mill of the present invention and applying a conventional slurry dispersing technology to a steel plate. The MgO film on the vertical axis in the figure is a film obtained by quantifying a glass film with MgO and expressing the amount in g / m ² .

Claims (5)

(57) [Claims] 1. A method for producing a grain-oriented electrical steel sheet, comprising: applying an annealing separator containing MgO as a main component to a decarburized sheet for grain-oriented electrical steel in a slurry state ; The slurry in which the separating agent is dispersed in water is
Particle beads are placed in a cylindrical container with a disk-shaped rotating body.
After crushing using a filled bead mill, crushing the annealing separator particles and activating the particle surface , the annealing separator
A method for producing a grain-oriented electrical steel sheet having extremely excellent film properties and magnetic properties, characterized by applying a slurry to a steel sheet. 2. A decarburized plate for grain-oriented electrical steel mainly comprising MgO.
And then apply the slurry in the form of a slurry and then dry.
Method for producing grain-oriented electrical steel sheet by finish annealing
In the above, the annealing separator is dispersed in water to form a slurry.
At the same time, a disk-shaped rotating body was provided for the slurry.
Use a bead mill filled with fine particle beads in a cylindrical container
To separate the particles of the annealing separator and to activate the surface of the particles.
After annealing, apply annealing separator slurry to steel sheet
Extremely excellent film properties and magnetic properties
Manufacturing method of grain-oriented electrical steel sheet. 3. A bead mill for disintegrating a slurry and another bead mill.
Use mechanical, shock or vibrational means to
It is characterized in that it performs grinding and activation of the particle surface.
3. Extreme coating and magnetic properties according to claim 1 or 2.
And excellent method for producing grain-oriented electrical steel sheets. 4. A method of crushing and dispersing an annealed separating agent slurry and activating an annealed separating agent particle surface to obtain an annealed separating agent slurry having an average particle diameter of 10 μm or less measured by a laser method and a liquid temperature of 10 μm. 4. The method for producing a grain-oriented electrical steel sheet according to claim 1 , wherein the viscosity measured by a B-type viscometer at 20 DEG C. is 20 to 200 cPs and applied to the steel sheet. 5. An annealing separator for crushing, dispersing and activating the particle surface of the annealing separator is MgO,
l: 0.001 to 0.05%, B: 0.01 to 0.15
%, S: 0.01 to 0.40%, CaO: 0.1 to 1.%.
5%, CAA value at a liquid temperature of 30 ° C. 50 to 250
Ti, Sb, Sr, A per 100 parts by weight of MgO per second
oxides and hydroxides of 1, Zr, Ca, Mg, Na, K,
Chlorides, sulfides, one or two or more kinds, according to claim 1, 2, 3 or 4, wherein the use of annealing separator agent added from 0.1 to 10 parts by weight selected from among sulfate A method for producing a grain-oriented electrical steel sheet having extremely excellent coating and magnetic properties.