The present invention relates to grain-oriented electrical steel sheets. Background technology [0002] A grain-oriented electrical steel sheet contains 7% by mass or less of Si and has a secondary recrystallization texture that is aggregated in the {110}<001> orientation (Goss orientation). The {110}<001> orientation means that the {110} plane of the crystal is parallel to the rolling surface and the <001> axis of the crystal is parallel to the rolling direction. [0003] The magnetic properties of grain-oriented electrical steel sheets are greatly affected by the degree of integration in the {110}<001> orientation. In particular, the relationship between the rolling direction of the steel sheet, which is the main magnetization direction when the steel sheet is used, and the crystal <001> direction, which is the direction of easy magnetization, is considered to be important. Therefore, in recent practical grain-oriented electrical steel sheets, the angle formed by the crystal <001> direction and the rolling direction is controlled to be within the range of about 5°. [0004] The deviation between the actual crystal orientation of the grain-oriented electrical steel sheet and the ideal {110} <001> orientation is the deviation angle α around the normal direction Z to the rolling surface, the deviation angle β around the direction C perpendicular to the rolling direction, and the rolling direction It can be expressed by three components of the deviation angle γ around L. [0005] FIG. 1 is a schematic diagram illustrating the deviation angle α, the deviation angle β, and the deviation angle γ. As shown in FIG. 1, the deviation angle α is the angle between the <001> direction of the crystal projected onto the rolled surface and the rolling direction L when viewed from the normal direction Z of the rolled surface. The deviation angle β is the angle formed by the <001> direction of the crystal projected on the L cross section (the cross section normal to the direction perpendicular to the rolling direction) and the rolling direction L when viewed from the rolling direction C (sheet width direction). be. The deviation angle γ is the angle formed by the <110> direction of the crystal projected on the C section (the section normal to the rolling direction) when viewed from the rolling direction L and the normal direction Z to the rolling surface. [0006] Of the deviation angles α, β, and γ, the deviation angle β is known to affect magnetostriction. Note that magnetostriction is a phenomenon in which the shape of a magnetic material changes due to the application of a magnetic field. Grain-oriented electrical steel sheets used in transformers and the like are required to have low magnetostriction because magnetostriction causes vibration and noise. [0007] For example, Patent Documents 1 to 3 disclose controlling the deviation angle β. Further, in addition to the deviation angle β, controlling the deviation angle α is disclosed in Patent Documents 4 and 5. Furthermore, Patent Document 6 discloses a technique for improving iron loss characteristics by classifying the degree of accumulation of crystal orientations in more detail using the misalignment angles α, the misalignment angles β, and the misalignment angles γ as indexes. [0008] In addition, Patent Documents 7 to 9, for example, disclose that not only the magnitude and average value of the deviation angles α, β, and γ are controlled but also the variation (deviation) is included. Furthermore, Patent Documents 10 to 12 disclose adding Nb, V, or the like to grain-oriented electrical steel sheets. [0009] In addition, Patent Document 13 proposes a method of predicting transformer noise caused by magnetostriction. In this method of predicting transformer noise, a value called magnetostriction velocity level (Lva), which is obtained by differentiating the magnetostriction waveform during AC excitation with time and converting it into velocity and applying A-weighted hearing correction, which is the frequency characteristic of human hearing, is used. . Patent Document 14 discloses reducing transformer noise by reducing the magnetostrictive velocity level (Lva). For example, Patent Document 14 discloses a technique for reducing the magnetostriction rate level by introducing linear strain on the surface of the steel sheet to refine the magnetic domains, thereby reducing the transformer noise caused by the grain-oriented electrical steel sheet. there is prior art documents patent literature [0010] Patent Document 1: Japanese Patent Application Laid-Open No. 2001-294996 Patent Document 2: Japanese Patent Application Laid-Open No. 2005-240102 Patent Document 3: Japanese Patent Application Laid-Open No. 2015-206114 Patent Document 4: Japanese Patent Application Laid-Open No. 2004-60026 Patent Document 5: International Publication No. 2016/056501 Patent Document 6: Japanese Patent Application Laid-Open No. 2007-314826 Patent Document 7: Japanese Patent Application Laid-Open No. 2001-192785 Patent Document 8: Japanese Patent Application Laid-Open No. 2005-240079 Patent Document 9: Japanese Patent Application Laid-Open No. 2012-52229 Patent Document 10: Japanese Patent Application Laid-Open No. 52-24116, Patent Document 11: Japanese Patent Laid-Open No. 02-200732 Patent Document 12: Japanese Patent No. 4962516 Patent Document 13: Japanese Patent No. 3456742 Patent Document 14: Japanese Patent Application Laid-Open No. 2017-128765 SUMMARY OF THE INVENTION Problems to be Solved by the Invention [0011] As a result of studies by the present inventors, it can be said that the conventional techniques disclosed in Patent Documents 1 to 9, in particular, do not sufficiently reduce magnetostriction in spite of controlling the crystal orientation. In particular, it has been found that the magnetostrictive velocity level (Lva) is sometimes insufficiently reduced. [0012] In addition, the conventional techniques disclosed in Patent Documents 10 to 12 simply contain Nb and V, and cannot be said to sufficiently reduce the magnetostriction velocity level (Lva). [0013] Further, Patent Documents 13 and 14 disclose the relationship between the magnetostriction rate level (Lva) and transformer noise, but the magnetostriction rate level (Lva ), but does not control the texture of the steel sheet, and the reduction of the magnetostriction rate level (Lva) cannot be said to be sufficient. [0014] The present invention aims to provide a grain-oriented electrical steel sheet with an improved magnetostriction rate level (Lva), based on the current situation where grain-oriented electrical steel sheets that enable noise reduction in transformers are required. In particular, the object is to provide a grain-oriented electrical steel sheet which is excellent in iron loss properties and has an improved magnetostriction rate level (Lva) in a medium-to-high magnetic field region (especially a magnetic field of about 1.7 to 1.9 T). . Means to solve problems [0015] The gist of the present invention is as follows. [0016] (1) The grain-oriented electrical steel sheet according to one aspect of the present invention is, in mass%, Si: 2.0 to 7.0%, Nb: 0 to 0.030%, V: 0 to 0.030%, Mo : 0-0.030%, Ta: 0-0.030%, W: 0-0.030%, C: 0-0.0050%, Mn: 0-1.0%, S: 0-0. 0150%, Se: 0-0.0150%, Al: 0-0.0650%, N: 0-0.0050%, Cu: 0-0.40%, Bi: 0-0.010%, B: 0-0.080%, P: 0-0.50%, Ti: 0-0.0150%, Sn: 0-0.10%, Sb: 0-0.10%, Cr: 0-0.30 %, Ni: 0 to 1.0%, the balance being Fe and impurities, a grain-oriented electrical steel sheet having a texture oriented in the Goss orientation, The angle of deviation from the ideal Goss orientation with the rolling surface normal direction Z as the axis of rotation is defined as α, the angle of deviation from the ideal Goss orientation with the direction C perpendicular to rolling as the axis of rotation is defined as β, and the rolling direction L is defined as The angle of deviation from the ideal Goss orientation as the axis of rotation is defined as γ, and the angle of deviation of the crystal orientation measured at two measurement points adjacent to each other on the plate surface with an interval of 1 mm is (α 1, β 1, γ 1) and (α 2, β 2, γ 2), where the boundary condition BAα is |α 2−α 1|≧0.5°, and the average grain size in the direction perpendicular to the rolling direction C obtained based on the boundary condition BAα is defined as the grain size RAα C, the boundary condition BAβ is |β 2−β 1|≧0.5°, and the average grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAβ is defined as the grain size RAβ C. The boundary condition BAγ is |γ 2−γ 1|≧0.5°, the average grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAγ is defined as the grain size RAγ C, and the boundary condition BB is [ (α 2 - α 1) 2 + (β 2 - β 1) 2 + (γ 2 - γ 1) 2] 1/2 ≥ 2.0°, There is a grain boundary that satisfies the boundary condition BAγ but does not satisfy the boundary condition BB, the grain size RAα C and the grain size RAγ C satisfy RAγ C orientation, which is the axis of easy magnetization, in the rolling direction, and the deviation angle γ caused by the crystal rotation around the rolling direction L is considered to have little effect on the magnetic properties. has been thought. Therefore, in a general grain-oriented electrical steel sheet, nuclei of secondary recrystallized grains whose orientation is precisely controlled mainly with respect to the misalignment angle α and the misalignment angle β are generated, and the grains are grown while maintaining the crystal orientation. It is manufactured as Conventionally, it was considered difficult to precisely control the deviation angle γ after controlling the deviation angles α and β. [0033] Therefore, the present inventors considered growing the crystals while changing the orientation, instead of growing the grains while maintaining the crystal orientation at the stage of growth of the secondary recrystallized grains. As a result, during the growth of the secondary recrystallized grains, a large number of localized and small-angle orientation changes (sub-grain boundaries), which were not conventionally recognized as grain boundaries, were generated, resulting in a single secondary recrystallized grain. It has been found that the state in which the magnetostriction velocity level (Lva) is reduced in a medium-to-high magnetic field region is advantageous if the magnetostriction is divided into small regions with slightly different deviation angles. [0034] In particular, it is possible to divide the secondary recrystallized grains into small regions by subgrain boundaries, and then control the relationship between the deviation angle γ and the deviation angle α and the relationship between the deviation angle γ and the deviation angle β. found to be important. Specifically, with respect to the direction perpendicular to the rolling direction C, if more subgrain boundaries related to changes in the misalignment angle γ are generated than subgrain boundaries related to changes in the misalignment angles α and β, iron It has been found that the magnetostriction velocity level (Lva) in a medium-to-high magnetic field region can be improved in addition to excellent loss characteristics. [0035] In addition, it is important to consider the factors that make the orientation change itself more likely to occur and the factors that cause the orientation change to occur continuously in one crystal grain for the control of the orientation change described above. I found out. Then, in order to facilitate the occurrence of the orientation change itself, it is effective to start the secondary recrystallization at a lower temperature. . Furthermore, by using a conventionally used inhibitor such as AlN in an appropriate temperature and atmosphere, it is possible to continuously cause the orientation change to occur up to a high temperature region in one crystal grain during secondary recrystallization. Confirmed that it can be done. [0036] The grain-oriented electrical steel sheet according to this embodiment will be described in detail below. [0037] In the grain-oriented electrical steel sheet according to this embodiment, the secondary recrystallized grains are divided into a plurality of regions with slightly different deviation angles. That is, in the grain-oriented electrical steel sheet according to the present embodiment, in addition to the grain boundaries with a relatively large angle difference corresponding to the grain boundaries of the secondary recrystallized grains, the local and has a small tilt grain boundary. [0038] In addition, in the grain-oriented electrical steel sheet according to the present embodiment, the relationship between the deviation angle γ and the deviation angle α and the relationship between the deviation angle γ and the deviation angle β with respect to the rolling direction C are preferably controlled. . [0039] Specifically, the grain-oriented electrical steel sheet according to the present embodiment has Si: 2.0 to 7.0%, Nb: 0 to 0.030%, V: 0 to 0.030%, Mo : 0-0.030%, Ta: 0-0.030%, W: 0-0.030%, C: 0-0.0050%, Mn: 0-1.0%, S: 0-0. 0150%, Se: 0-0.0150%, Al: 0-0.0650%, N: 0-0.0050%, Cu: 0-0.40%, Bi: 0-0.010%, B: 0-0.080%, P: 0-0.50%, Ti: 0-0.0150%, Sn: 0-0.10%, Sb: 0-0.10%, Cr: 0-0.30 %, Ni: 0 to 1.0%, the balance being Fe and impurities, and having a grain-oriented electrical steel sheet having a texture oriented in the Goss orientation, The angle of deviation from the ideal Goss orientation with the rolling surface normal direction Z as the axis of rotation is defined as α, the angle of deviation from the ideal Goss orientation with the direction C perpendicular to rolling as the axis of rotation is defined as β, and the rolling direction L is defined as The angle of deviation from the ideal Goss orientation as the axis of rotation is defined as γ, and The deviation angles of the crystal orientation measured at two measurement points adjacent to each other on the plate surface with an interval of 1 mm are expressed as (α 1, β 1, γ 1) and (α 2, β 2, γ 2), and the boundary The condition BAα is |α 2−α 1|≧0.5°, the average grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAα is defined as the grain size RAα C, and the boundary condition BAβ is |β 2− β 1 |≧0.5°, the average grain size in the direction perpendicular to rolling C determined based on the boundary condition BAβ is defined as the grain size RAβ C, and the boundary condition BAγ is |γ 2−γ 1|≧0.5 °, the average crystal grain size in the direction perpendicular to the rolling direction C obtained based on the boundary condition BAγ is defined as the grain size RAγ C, and the boundary condition BB is [(α 2-α 1) 2 + (β 2-β 1) 2 + ( γ 2−γ 1) 2] When defining 1/2≧2.0°, 　There exists a grain boundary that satisfies the boundary condition BAγ but does not satisfy the boundary condition BB, The grain size RAαC and the grain size RAγC satisfy RAγC orientations are distinguished, namely, "actual crystal {110}<001> orientation" and "ideal {110}<001> orientation". The reason for this is that, in this embodiment, it is necessary to distinguish between the {110}<001> orientation when indicating the crystal orientation of a practical steel sheet and the {110}<001> orientation as an academic crystal orientation. It's for. [0047] In general, when measuring the crystal orientation of a recrystallized practical steel sheet, the crystal orientation is defined without strictly distinguishing an angle difference of about ±2.5°. In the case of conventional grain-oriented electrical steel sheets, the angular range of about ±2.5° centered on the geometrically strict {110} <001> orientation is defined as the “{110} <001> orientation”. . However, in this embodiment, it is necessary to clearly distinguish an angular difference of ±2.5° or less. [0048] For this reason, in the present embodiment, when the orientation of the grain-oriented electrical steel sheet is meant in a practical sense, it is simply described as "{110} <001> orientation (Goss orientation)" as usual. On the other hand, when referring to the {110} <001> orientation as a geometrically strict crystal orientation, in order to avoid confusion with the {110} <001> orientation used in conventional publications, etc., " “ideal {110}<001> orientation (ideal Goss orientation)”. [0049] Therefore, in the present embodiment, for example, there is a statement that "the {110}<001> orientation of the grain-oriented electrical steel sheet according to the present embodiment deviates from the ideal {110}<001> orientation by 2°." Sometimes. [0050] Also, in this embodiment, the following four angles α, β, γ, and φ related to the crystal orientations observed in grain-oriented electrical steel sheets are used. [0051] Deviation angle α: The deviation angle from the ideal {110}<001> orientation around the normal direction Z of the rolled surface of the crystal orientation observed in the grain-oriented electrical steel sheet. Deviation angle β: The deviation angle of the crystal orientation observed in the grain-oriented electrical steel sheet from the ideal {110} <001> orientation around the direction C perpendicular to the rolling. Deviation angle γ: The deviation angle of the crystal orientation observed in the grain-oriented electrical steel sheet from the ideal {110} <001> orientation around the rolling direction L. A schematic diagram of the deviation angle α, the deviation angle β, and the deviation angle γ is shown in FIG. [0052] Angle φ: The deviation angles of the crystal orientation measured at two measurement points adjacent to each other on the rolled surface of the grain-oriented electrical steel sheet with an interval of 1 mm are expressed as (α 1, β 1, γ 1) and (α More about this source textSource text required for additional translation information Send feedback Side panels History Saved Contribute 5,000 character limit. Use the arrows to translate more.2, β 2, γ 2), the angle given by φ = [(α 2 - α 1) 2 + (β 2 - β 1) 2 + (γ 2 - γ 1) 2] 1/2. This angle φ is sometimes described as a "spatial three-dimensional orientation difference". [0053] 2. Grain boundaries of grain-oriented electrical steel sheets In the grain-oriented electrical steel sheet according to the present embodiment, in order to control the relationship between the deviation angle γ and the deviation angle α and the relationship between the deviation angle γ and the deviation angle β with respect to the direction C perpendicular to the rolling, It takes advantage of local crystallographic orientation changes that occur during the growth of secondary recrystallized grains, to the extent not conventionally recognized as grain boundaries. In the following description, the orientation change that occurs so as to divide the inside of one secondary recrystallized grain into small regions with slightly different deviation angles may be described as "switching". [0054] Furthermore, the grain boundaries that divide the inside of the secondary recrystallized grains are sometimes described as "subgrain boundaries", and the grains that are distinguished by the grain boundaries including the subgrain boundaries are sometimes described as "subgrains". In addition, a crystal grain boundary (a grain boundary that satisfies the boundary condition BAα) considering the angle difference of the deviation angle α is described as "α grain boundary", and a crystal grain distinguished by using the α grain boundary as a boundary is described as "α crystal grain". , a grain boundary (a grain boundary that satisfies the boundary condition BAβ) considering the angle difference of the deviation angle β is described as "β grain boundary", and a crystal grain distinguished by using the β grain boundary as a boundary is described as "β grain", A grain boundary (a grain boundary that satisfies the boundary condition BAγ) considering the angle difference of the deviation angle γ can be described as "γ grain boundary", and a crystal grain distinguished by using the γ grain boundary as a boundary can be described as "γ grain". be. [0055] In addition, the magnetostriction velocity level (Lva) in the medium-high magnetic field region, which is a characteristic related to the present embodiment, may be simply referred to as "magnetostriction velocity level" in the following description. [0056] The change in crystal orientation is about 1° (less than 2°), and it is thought that the above switching occurs in the process of continuing the growth of secondary recrystallized grains. Although the details will be described later in relation to the manufacturing method, it is important to grow the secondary recrystallized grains in a situation where switching is likely to occur. For example, it is important to start the secondary recrystallization at a relatively low temperature by controlling the primary recrystallized grain size, and to continue the secondary recrystallization to a high temperature by controlling the type and amount of the inhibitor. [0057] The reason why the control of the deviation angle affects the magnetic properties is not necessarily clear, but it is presumed as follows. [0058] Magnetization behavior generally occurs due to movement of 180° magnetic domains and magnetization rotation from the direction of easy magnetization. This magnetic domain movement and magnetization rotation are particularly affected by the continuity of the magnetic domain or the continuity of the magnetization direction with adjacent crystal grains in the vicinity of the grain boundary, and the orientation difference with the adjacent grains is linked to the magnitude of the disturbance in magnetization behavior. It is thought that In the switching controlled in this embodiment, switching (local orientation change) occurs frequently within one secondary recrystallized grain, thereby reducing the relative orientation difference with adjacent grains and increasing the orientation. It is considered that this acts to increase the continuity of crystal orientation in the entire electrical steel sheet. [0059] In this embodiment, several types of boundary conditions are defined for changes in crystal orientation including switching. In this embodiment, the definition of "grain boundary" based on these boundary conditions is important. [0060] At present, the crystal orientation of grain-oriented electrical steel sheets that are practically manufactured is controlled so that the deviation angle between the rolling direction and the <001> direction is approximately 5° or less. This control is the same for the grain-oriented electrical steel sheet according to the present embodiment. For this reason, when defining the "grain boundary" of a grain-oriented electrical steel sheet, generally the definition of a grain boundary (high-angle grain boundary), "a boundary where the orientation difference between adjacent regions is 15° or more" is applied. I can't. For example, in a conventional grain-oriented electrical steel sheet, macro-etching of the surface of the steel sheet reveals the grain boundary, and the crystal orientation difference between both side regions of this grain boundary is usually about 2 to 3 degrees. [0061] In this embodiment, as will be described later, it is necessary to strictly define boundaries between crystals. For this reason, a method based on visual inspection, such as macroetching, is not adopted as a method for measuring the grain size. [0062] In this embodiment, in order to specify grain boundaries, a measurement line including at least 500 measurement points is set at intervals of 1 mm in the direction perpendicular to the rolling direction to measure the crystal orientation. For example, crystal orientation may be measured by an X-ray diffraction method (Laue method). The Laue method is a method of irradiating a steel plate with an X-ray beam and analyzing transmitted or reflected diffraction spots. By analyzing the diffraction spots, it is possible to identify the crystal orientation of the location irradiated with the X-ray beam. By changing the irradiation position and analyzing the diffraction spots at a plurality of positions, the crystal orientation distribution at each irradiation position can be measured. The Laue method is a technique suitable for measuring the crystal orientation of metal structures having coarse grains. [0063] Although at least 500 measurement points for crystal orientation are sufficient, it is preferable to appropriately increase the number of measurement points according to the size of the secondary recrystallized grains. For example, if less than 10 secondary recrystallized grains are included in the measurement line when the number of measurement points for measuring crystal orientation is 500, 10 or more secondary recrystallized grains are included in the measurement line. It is preferable to extend the above measurement line by increasing the number of measurement points at intervals of 1 mm. [0064] The crystal orientation is measured on the rolled surface at intervals of 1 mm, and then the deviation angle α, the deviation angle β, and the deviation angle γ are specified for each measurement point. Based on the deviation angle at each specified measurement point, it is determined whether or not a grain boundary exists between two adjacent measurement points. Specifically, it is determined whether or not two adjacent measurement points satisfy the above boundary condition BA and/or boundary condition BB. [0065] Specifically, when the deviation angles of the crystal orientation measured at two adjacent measurement points are respectively expressed as (α 1, β 1, γ 1) and (α 2, β 2, γ 2), the boundary condition BAα is defined as |α 2−α 1|≧0.5°, the boundary condition BAβ is defined as |β 2−β 1|≧0.5°, and the boundary condition BAγ is defined as |γ 2−γ 1|≧0 .5° and the boundary condition BB is defined as [(α 2 - α 1) 2 + (β 2 - β 1) 2 + (γ 2 - γ 1) 2] 1/2 ≥ 2.0°. It is determined whether or not a grain boundary satisfying boundary condition BA and/or boundary condition BB exists between two adjacent measurement points. [0066] A grain boundary that satisfies the boundary condition BB has a three-dimensional spatial orientation difference (angle φ) between two points sandwiching the grain boundary of 2.0° or more, and this grain boundary has been recognized by macroetching. It can be said that the grain boundaries are almost the same as those of conventional secondary recrystallized grains. [0067] In addition to the grain boundaries that satisfy the boundary condition BB, the grain-oriented electrical steel sheet according to the present embodiment has grain boundaries that are strongly related to "switching", specifically, the grain boundaries that satisfy the boundary condition BAγ and the boundary condition Grain boundaries that do not satisfy BB are present at a relatively high frequency. A grain boundary defined in this way corresponds to a grain boundary that divides a single secondary recrystallized grain into small regions with slightly different misalignment angles. [0068] Each grain boundary described above can also be obtained using other measurement data. However, considering the deviation from the actual situation due to the labor of measurement and different data, the crystal orientation deviation angle obtained from the same measurement line (at least 500 measurement points at 1 mm intervals on the rolled surface) is used. It is preferable to determine each grain boundary as described above. [0069] In the grain-oriented electrical steel sheet according to the present embodiment, in addition to grain boundaries that satisfy the boundary condition BB, there are grain boundaries that satisfy the boundary condition BAγ but do not satisfy the boundary condition BB at a relatively high frequency. The inside of the recrystallized grain is divided into small regions with slightly different deviation angles. [0070] For example, the present embodiment is characterized by dividing the interior of the secondary recrystallized grains into small regions with slightly different deviation angles, so that the sub-grain boundaries that divide the interior of the secondary recrystallized grains are different from those of the conventional secondary recrystallized grains. It is preferable that they exist at a relatively higher frequency than recrystallized grain boundaries. [0071] Specifically, when the crystal orientation is measured at least 500 measurement points at intervals of 1 mm on the rolled surface, the deviation angle is specified at each measurement point, and the boundary conditions are determined at two adjacent measurement points, It is sufficient that the "grain boundaries satisfying the boundary condition BAγ" exist at a rate of 1.05 times or more the "grain boundaries satisfying the boundary condition BB". That is, when the boundary conditions are determined as described above, the value obtained by dividing "the number of boundaries satisfying the boundary condition BAγ" by "the number of boundaries satisfying the boundary condition BB" should be 1.05 or more. In this embodiment, when the above value is 1.05 or more, it is determined that grain boundaries that satisfy the boundary condition BAγ but do not satisfy the boundary condition BB exist in the grain-oriented electrical steel sheet. [0072] The upper limit of the value obtained by dividing "the number of boundaries satisfying the boundary condition BAγ" by "the number of boundaries satisfying the boundary condition BB" is not particularly limited. For example, this value may be 80 or less, may be 40 or less, or may be 30 or less. [0073] 3. Grain size of grain oriented electrical steel sheet In the grain-oriented electrical steel sheet according to the present embodiment, after dividing the secondary recrystallized grains into small regions by subgrain boundaries, the relationship between the deviation angle γ and the deviation angle α, and the deviation angle γ and the deviation angle β It is important to control the relationship with Specifically, with respect to the rolling perpendicular direction C, more sub-boundaries are produced that are associated with changes in the misalignment angle γ than those associated with changes in the misalignment angles α and β. [0074] That is, the average grain size in the direction perpendicular to rolling C determined based on the boundary condition BAα is defined as grain size RAα C, and the average grain size in the direction perpendicular to rolling C determined based on boundary condition BAβ is defined as grain size RAβ C. When the average crystal grain size in the direction perpendicular to the rolling direction C obtained based on the boundary condition BAγ is defined as the grain size RAγC, The grain size RAα C and the grain size RAγ C satisfy the following (Formula 1), and the grain size RAβ C and the grain size RAγ C satisfy the following (Formula 2). RAγ C orientation are generated and grown by secondary recrystallization. Therefore, the secondary recrystallized grains grow from the coil end side where the temperature rise precedes toward the coil center side where the temperature rise is delayed. In such a manufacturing method, for example, if the coil width is 1000 mm, the upper limit of the particle diameter RBC can be 500 mm, which is about half the coil width. Of course, this embodiment does not exclude that the entire width of the coil is of grain size RBC. [0092] Also, in the grain-oriented electrical steel sheet according to the present embodiment, the grain size RAγC is preferably 40 mm or less. [0093] The smaller the value of the grain size RAγC, the higher the frequency of occurrence of switching in the direction perpendicular to the rolling direction, so the grain size RAγC is preferably 40 mm or less. More preferably, the grain size RAγC is 30 mm or less. [0094] The lower limit of the particle size RAγC is not particularly limited. In this embodiment, since the crystal orientation measurement interval is 1 mm, the minimum value of the grain size RAγC is 1 mm. However, in the present embodiment, for example, by setting the measurement interval to be less than 1 mm, steel sheets having a grain size RAγC of less than 1 mm are not excluded. However, since the switching is accompanied by the presence of lattice defects in the crystal, albeit slightly, there is concern that if the frequency of switching is too high, the magnetic properties may be adversely affected. In consideration of industrial feasibility, the preferred lower limit of the particle size RAγC is 5 mm. [0095] It should be noted that in the measurement of the grain size of the grain-oriented electrical steel sheet according to the present embodiment, the maximum grain size is 2 mm for each grain. Therefore, grain size measurement (orientation measurement of at least 500 points at intervals of 1 mm on the rolled surface) is performed at positions sufficiently distant in the direction that defines the grain size and in the direction orthogonal to the steel plate surface, that is, measurement of different crystal grains. It is preferable to carry out at a total of 5 or more positions such that On top of that, by averaging all the particle sizes obtained by measurements at five or more points in total, the above ambiguity can be resolved. For example, each of the grain sizes described above may be measured at 5 or more locations sufficiently separated in the rolling direction, and the average grain diameter may be obtained by performing azimuth measurement at a total of 2500 or more measurement points. [Claim 1] in % by mass, 　　Si: 2.0 to 7.0%, 　　Nb: 0 to 0.030%, 　　V: 0 to 0.030%, 　　Mo: 0 to 0.030%, 　Ta: 0 to 0.030%, W: 0-0.030%, 　　C: 0 to 0.0050%, 　　Mn: 0 to 1.0%, 　　S: 0 to 0.0150%, Se: 0 to 0.0150%, Al: 0 to 0.0650%, 　　N: 0 to 0.0050%, 　　Cu: 0 to 0.40%, Bi: 0 to 0.010%, 　　B: 0 to 0.080%, 　　P: 0 to 0.50%, 　Ti: 0 to 0.0150%, Sn: 0 to 0.10%, Sb: 0 to 0.10%, Cr: 0 to 0.30%, Ni: 0 to 1.0%, and has a chemical composition with the balance consisting of Fe and impurities, In a grain-oriented electrical steel sheet having a texture oriented in the Goss orientation, 　The angle of deviation from the ideal Goss orientation with the normal direction Z of the rolling surface as the axis of rotation is defined as α, 　The angle of deviation from the ideal Goss orientation with the direction C perpendicular to the rolling as the axis of rotation is defined as β, 　The deviation angle from the ideal Goss orientation with the rolling direction L as the axis of rotation is defined as γ, The deviation angles of the crystal orientation measured at two measurement points adjacent to each other on the plate surface with an interval of 1 mm are expressed as (α 1, β 1, γ 1) and (α 2, β 2, γ 2), The boundary condition BAα is |α 2−α 1|≧0.5°, and the average crystal grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAα is defined as the grain size RAα C, The boundary condition BAβ is |β 2-β 1|≧0.5°, and the average crystal grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAβ is defined as the grain size RAβ C, The boundary condition BAγ is |γ 2−γ 1|≧0.5°, and the average crystal grain size in the direction perpendicular to rolling C obtained based on the boundary condition BAγ is defined as the grain size RAγ C, When the boundary condition BB is defined as [(α 2 - α 1) 2 + (β 2 - β 1) 2 + (γ 2 - γ 1) 2] 1/2 ≥ 2.0°, There exists a grain boundary that satisfies the boundary condition BAγ but does not satisfy the boundary condition BB, the particle size RAα C and the particle size RAγ C satisfy RAγ C