Orally administered substance and method for producing same, and magnetic ink used to produce orally administered substance

Abstract

Provided is an orally administered substance provided with a magnetic marker that can be detected easily by a magnetic sensor even with a small amount applied. The orally administered substance contains a composition for oral administration and a magnetic marker provided on the composition for oral administration. The magnetic marker contains a magnetic powder and a binder and has a squareness ratio of 0.40 or more.

Description

Oral dosage form, manufacturing method thereof, and magnetic ink for use in manufacturing oral dosage form

[0001] The present disclosure relates to oral dosage forms and methods for producing the same, as well as magnetic inks for use in producing oral dosage forms.

[0002] Orally administered compositions containing a magnetic material (magnetic marker) that can be detected by a magnetic sensor placed outside the body are known in order to confirm whether or not the orally administered composition, such as a pharmaceutical, has been taken or ingested (see, for example, Patent Document 1). Patent Document 1 describes that iron oxide, particularly magnetite or maghemite, is preferred as the magnetic material, and that these magnetic materials desirably have a residual magnetization of at least 0.003 emu or more after magnetization treatment.

[0003] Examples of ways in which a magnetic material (magnetic marker) can be incorporated into a composition for oral administration include incorporating the magnetic material as a core tablet in the composition for oral administration (hereinafter referred to as the "core tablet method"), coating the surface of the composition for oral administration with a magnetic material (hereinafter referred to as the "coating method"), and printing the magnetic material on at least one side of the surface of the composition for oral administration (hereinafter referred to as the "printing method"). Note that when the type and amount of magnetic material are the same, tablets containing the magnetic material as a core tablet are said to exhibit greater residual magnetization.

[0004] Japanese Patent Application Laid-Open No. 2020-70246

[0005] The inventors considered that, among the various forms of magnetic material (magnetic marker) disclosed in Patent Document 1, magnetic markers formed by printing methods have the advantage over those formed by other methods in that the application area and application shape can be changed as desired.

[0006] However, as suggested in Patent Document 1, the residual magnetization of magnetic materials formed by printing methods is smaller than that of core tablet methods. Furthermore, when applying magnetic material by printing methods, if the entire surface is not coated to obtain a desired coating shape, the amount of magnetic material applied is reduced compared to coating methods, which is thought to result in smaller residual magnetization. Therefore, it is expected that oral administration products in which a magnetic material is formed on the surface of an orally administered composition by printing methods will be more difficult to detect with a magnetic sensor than oral administration products in which a magnetic material is formed by other methods.

[0007] Therefore, magnetic markers that are easy to detect with a magnetic sensor are desired, even when they are formed by printing. To achieve this goal, it is assumed that improving the magnetic properties of the magnetic marker (especially the magnetic material contained in the magnetic marker) would be effective, but what magnetic properties should be improved and how to improve them has not been investigated until now.

[0008] Therefore, an object of one embodiment of the present invention is to provide an oral dosage form having a magnetic marker that can be easily detected by a magnetic sensor even with a small amount of application.Another embodiment of the present invention is to provide a method for producing such an oral dosage form.A still further embodiment of the present invention is to provide a magnetic ink for use in producing oral dosage forms.

[0009] A first aspect of the present invention is an orally administered product comprising: a composition for oral administration; and a magnetic marker provided in the composition for oral administration, wherein the magnetic marker comprises a magnetic powder and a binder and has a squareness ratio of 0.40 or more.

[0010] A second aspect of the present invention is the oral administration product according to the first aspect, wherein the squareness ratio of the magnetic marker is 0.50 or more.

[0011] Aspect 3 of the present invention is the oral administration product according to aspect 1, wherein the squareness ratio of the magnetic marker is 0.55 or more.

[0012] A fourth aspect of the present invention is the oral administration product according to the first aspect, wherein the squareness ratio of the magnetic marker is 0.60 or more.

[0013] Aspect 5 of the present invention is the oral administration product according to aspect 1, wherein the squareness ratio of the magnetic marker is 0.65 or more.

[0014] A sixth aspect of the present invention is the oral administration product according to any one of the first to fifth aspects, wherein the magnetic marker is provided on the surface of the composition for oral administration.

[0015] Aspect 7 of the present invention is the oral dosage form according to any one of aspects 1 to 6, which is a tablet or capsule.

[0016] Aspect 8 of the present invention is the oral administration composition according to any one of Aspects 1 to 7, wherein the magnetic powder comprises one or more selected from the group consisting of magnetite, maghemite, and barium ferrite.

[0017] A ninth aspect of the present invention is the orally administered composition according to any one of the first to eighth aspects, wherein the binder comprises one or more resins selected from the group consisting of vinyl resins, vinyl chloride resins, cellulose resins, urethane resins, epoxy resins, acrylic resins, and EB-curable resins.

[0018] A tenth aspect of the present invention is a method for producing an orally administered substance, comprising the steps of: preparing a composition for oral administration; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, and stirring the mixture at a peripheral speed of 4 m / s to 12 m / s for one hour or more, and then removing the beads to prepare magnetic ink; and using the magnetic ink to form a magnetic marker on the surface of the composition for oral administration, the magnetic marker forming step comprising applying the magnetic ink to the surface of the composition for oral administration, drying the applied magnetic ink, and applying a magnetic field to the magnetic ink during or after drying.

[0019] An eleventh aspect of the present invention is a method for producing an orally administered product, comprising the steps of: preparing a composition powder for forming an orally administered composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, and stirring the mixture at a peripheral speed of 4 m / sec or more and 12 m / sec or less for one hour or more, and then removing the beads to prepare a magnetic ink; producing a sheet-like or tablet-like magnetic marker from the magnetic ink; and arranging the magnetic marker inside the composition powder and compressing it to obtain an orally administered product.

[0020] A twelfth aspect of the present invention is a method for producing an oral administration product, comprising the steps of: preparing a composition powder for forming an oral administration composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / sec or more and 12 m / sec or less for 1 hour or more, and then removing the beads to prepare a magnetic ink; producing granular magnetic markers from the magnetic ink; mixing the composition powder and the magnetic markers to obtain a mixed powder; and compressing the mixed powder to obtain an oral administration product.

[0021] Aspect 13 of the present invention is characterized in that, in the step of preparing the magnetic ink, the amount of beads to be filled V ｂｅａｄｓ (L) and the amount of dispersion medium V ｄｉｓ-ｍ A method for producing an orally administered composition according to any one of Aspects 10 to 12, wherein the bead content is 55.00 vol% or more and 80.00 vol% or less when the total of (L) is 100 vol%.

[0022] A fourteenth aspect of the present invention is the method for producing an oral dosage form according to any one of Aspects 10 to 13, wherein in the step of preparing the magnetic ink, at least one of a plasticizer and a dispersant is further charged into the bead mill.

[0023] Aspect 15 of the present invention is a method for producing an oral dosage form according to any one of Aspects 10 to 14, wherein, in the step of preparing the magnetic ink, when the total mass of the materials filled into the bead mill excluding the beads is taken as 100 mass%, the magnetic powder content is 10.00 mass% or more and 50.00 mass% or less.

[0024] Aspect 16 of the present invention is a method for producing an orally administered drug according to any one of Aspects 10 to 15, wherein, in the step of preparing the magnetic ink, when the total mass of the materials filled in the bead mill excluding the beads is taken as 100 mass%, the binder content is 1.00 mass% or more and 10.00 mass% or less.

[0025] A seventeenth aspect of the present invention is the method for producing an orally administered composition according to any one of the tenth to sixteenth aspects, wherein the magnetic powder comprises one or more selected from the group consisting of magnetite, maghemite, and barium ferrite.

[0026] Aspect 18 of the present invention is the method for producing an orally administered composition according to any one of Aspects 10 to 17, wherein the binder comprises at least one selected from the group consisting of vinyl resins, vinyl chloride resins, cellulose resins, urethane resins, epoxy resins, acrylic resins, and EB-curable resins.

[0027] A nineteenth aspect of the present invention is a magnetic ink comprising a magnetic powder, a binder, and a dispersion medium, wherein the magnetic ink is dried under a magnetic field application environment to produce a magnetic material composition having a squareness ratio of 0.40 or more.

[0028] A twentieth aspect of the present invention is a magnetic ink comprising a magnetic powder, a binder, and a dispersion medium, wherein the magnetic ink is dried and then a magnetic field is applied to produce a magnetic material composition having a squareness ratio of 0.40 or more.

[0029] According to an embodiment of the present invention, it is possible to provide an oral administration product having a magnetic marker that can be easily detected by a magnetic sensor TMR element, and a method for manufacturing the same. Also, according to an embodiment of the present invention, it is possible to provide a magnetic ink for use in manufacturing the oral administration product.

[0030] FIG. 1 is a schematic top view of a tablet-form oral administration product according to one embodiment. FIG. 2A is a schematic cross-sectional view of a tablet-form oral administration product according to another embodiment. FIG. 2B is a schematic cross-sectional view of a tablet-form oral administration product according to another embodiment. FIG. 3 is a photograph of the top view of a tablet-form oral administration product sample prepared in Example 2. FIG. 4A is a graph plotting the squareness ratio of a magnetic material composition prepared from a magnetic ink versus the content of magnetic substance powder contained in the magnetic ink. FIG. 4B is a graph plotting the squareness ratio of a magnetic material composition prepared from the magnetic ink versus the content of magnetic substance powder contained in the magnetic ink. FIG. 4C is a graph plotting the squareness ratio of a magnetic material composition prepared from the magnetic ink versus the content of magnetic substance powder contained in the magnetic ink. FIG. 5A is a graph plotting the squareness ratio of a magnetic material composition prepared from the magnetic ink versus the content of beads used when stirring the magnetic ink. FIG. 5B is a graph plotting the squareness ratio of a magnetic material composition prepared from the magnetic ink versus the content of beads used when stirring the magnetic ink. Figure 5C is a graph plotting the squareness ratio of a magnetic material composition made from the magnetic ink against the content of beads used when stirring the magnetic ink. Figure 6A is a graph plotting the squareness ratio of a magnetic material composition made from the magnetic ink against the content of binder contained in the magnetic ink. Figure 6B is a graph plotting the squareness ratio of a magnetic material composition made from the magnetic ink against the content of binder contained in the magnetic ink. Figure 6C is a graph plotting the squareness ratio of a magnetic material composition made from the magnetic ink against the content of binder contained in the magnetic ink.

[0031] As a result of extensive research into providing an oral dosage form equipped with a magnetic marker, the inventors discovered that providing a magnetic marker with a squareness ratio of 0.40 or greater facilitates detection by a magnetic sensor. However, magnetic materials suitable for oral dosage forms have low squareness ratios (e.g., squareness ratios of 0.10 to 0.15). Therefore, it has been extremely difficult to obtain a magnetic marker with a squareness ratio of 0.40 or greater.

[0032] As a result of extensive research, the inventors have found that by appropriately controlling the conditions for preparing the slurry (magnetic ink) used to form the magnetic marker, it is possible to form a magnetic marker with a high squareness ratio, which was previously unobtainable. If an oral administration product is manufactured using this magnetic ink and is equipped with a magnetic marker, the ingestion or ingestion of the oral administration product can be detected by a magnetic sensor placed outside the body.

[0033] The magnetic marker used in the embodiment of the present invention is suitable for an orally administered product in which a thin film of the magnetic marker is disposed on the surface of the orally administered composition, since the amount of the magnetic marker required for detection by a magnetic sensor is small. However, the present invention is also applicable to an orally administered product in which the magnetic marker is disposed inside the orally administered composition.

[0034] Hereinafter, an orally administered product, a method for producing the same, and a magnetic ink according to an embodiment of the present invention will be described in detail.

[0035] <Oral Dosage Form 1> Fig. 1 is a schematic top view of a tablet-form oral dosage form 1 according to one embodiment, and Figs. 2A and 2B are schematic cross-sectional views of tablet-form oral dosage forms 2 and 3 according to other embodiments. Oral dosage forms 1, 2 and 3 according to the embodiments of the present invention comprise an orally administered composition 10 and magnetic markers 20, 30 and 40 provided in the orally administered composition 10. The magnetic markers 20, 30 and 40 can be provided on a surface 10s of the orally administered composition 10 (Fig. 1) or inside the orally administered composition 10 (Figs. 2A and 2B).

[0036] (Oral Administration Composition 10) The oral administration composition 10 may be a drug or a placebo tablet contained in the same capsule as the drug. When the oral administration composition 10 is a drug, its dosage form is preferably a tablet or capsule, and it is easy to provide magnetic markers 20, 30, 40 on the surface or inside of the oral administration composition 10. When the oral administration composition 10 is a placebo tablet, its dosage form is a tablet.

[0037] Tablets include plain tablets, film-coated tablets, sugar-coated tablets, enteric-coated tablets, and sustained-release tablets. Tablet shapes can be known shapes, such as round or oval tablets when viewed from above. Capsules include hard capsules and soft capsules. Capsule shapes can be known shapes, such as cylindrical, spherical, or oval.

[0038] (Magnetic Markers 20, 30, 40) In the orally administered product 1 illustrated in Fig. 1, the magnetic marker 20 is provided on the surface 10s of the orally administered composition 10. Each of the magnetic markers 20 shown in Figs. 1a to 1e is composed of five dots 201, but is not limited to this. For example, the shape of each dot may be elliptical instead of circular, or a single magnetic marker may be formed with an application amount equal to the total application amount of the five dots.

[0039] In the orally administered compositions 2 and 3 illustrated in FIGS. 2A and 2B, the magnetic markers 30 and 40 are provided inside the orally administered composition 10. One method for providing the magnetic marker inside the orally administered composition 10 is to place the magnetic marker 30 formed into a predetermined shape (e.g., a sheet or tablet) inside the orally administered composition 10 during molding, as shown in FIG. 2A. Another method is to form the magnetic marker 40 into granules, mix it with the composition powder for forming the orally administered composition 10, and then mold the mixture to produce the orally administered composition 3, as shown in FIG. 2B. Whether the magnetic marker 20 is on the surface 10s of the orally administered composition 10 as shown in FIG. 1 or the magnetic markers 30 and 40 are inside the orally administered composition 10 as shown in FIGS. 2A and 2B, the magnetic markers 20, 30, and 40 have similar squareness ratios, provided that the amount of magnetic marker and the type of magnetic powder used are equivalent.

[0040] 1 includes a magnetic powder and a binder. The magnetic powder in the magnetic marker 20 generates a magnetic field, so when an orally administered article 1 equipped with the magnetic marker 20 is orally ingested with a magnetic sensor (e.g., a magnetoresistive element (TMR element)) placed outside the body (mainly around the neck), the magnetic sensor can detect that the orally administered article 1 has passed through the esophagus.

[0041] The content of magnetic powder contained in the magnetic marker 20 is preferably 55.00 mass % or more and 91.00 mass % or less, and more preferably 65.00 mass % or more and 91.00 mass % or less.

[0042] As a result of intensive research, the inventors have found that in order to facilitate detection by a magnetic sensor (especially a TMR element), it is important to control the squareness ratio of the magnetic marker 20, and that if the squareness ratio of the magnetic marker 20 is 0.40 or more, an orally administered product 1 equipped with the magnetic marker 20 can be detected by a magnetic sensor (TMR element) placed outside the body (around the neck).

[0043] Patent Document 1 lists iron oxide as a suitable magnetic material. However, even when iron oxide powder used in pharmaceutical applications is magnetized using conventional methods, the squareness ratio is only about 0.15. Therefore, it is generally impossible to achieve a squareness ratio of 0.40 or more, as specified in this embodiment, for a magnetic marker 20 using iron oxide. However, after extensive research, the inventors have finally made it possible to form a magnetic marker with a squareness ratio of 0.40 or more by using magnetic ink prepared under specific conditions. Specific methods for preparing the magnetic ink will be described later.

[0044] The squareness ratio of the magnetic marker 20 is preferably 0.50, more preferably 0.55 or more, particularly preferably 0.60 or more, and most preferably 0.65 or more. Since a higher squareness ratio of the magnetic marker 20 is preferable, the upper limit is set to 1.0, which is the maximum value of the squareness ratio. The squareness ratio may be 0.90 or less, for example, 0.85 or less.

[0045] The squareness ratio can be converted into remanent magnetization. When the amount of magnetic ink applied is 0.5 mg and magnetite powder (theoretical value of saturation magnetization: 90 emu / g) is used as the magnetic powder, the converted value is as follows: Squareness ratio: 0.40, remanent magnetization: 36.0 emu / g, 0.018 emu Squareness ratio: 0.50, remanent magnetization: 45.0 emu / g, 0.023 emu Squareness ratio: 0.55, remanent magnetization: 49.5 emu / g, 0.025 emu Squareness ratio: 0.60, remanent magnetization: 54.0 emu / g, 0.027 emu Squareness ratio: 0.65, remanent magnetization: 58.5 emu / g, 0.029 emu Squareness ratio: 0.85, remanent magnetization: 76.5 emu / g, 0.038 emu Squareness ratio: 0.90, remanent magnetization: 82.0 emu / g, 0.041 emu Squareness ratio: 1.00, residual magnetization: 90.0 emu / g, 0.045 emu

[0046] When the amount of magnetic ink applied is 0.5 mg and maghemite powder (theoretical value of saturation magnetization: 70 emu / g) is used as the magnetic powder, the conversion values ​​are as follows. Squareness ratio: 0.40, remanent magnetization: 28.0 emu / g, 0.014 emu Squareness ratio: 0.50, remanent magnetization: 35.0 emu / g, 0.028 emu Squareness ratio: 0.55, remanent magnetization: 38.5 emu / g, 0.019 emu Squareness ratio: 0.60, remanent magnetization: 42.0 emu / g, 0.021 emu Squareness ratio: 0.65, remanent magnetization: 45.5 emu / g, 0.023 emu Squareness ratio: 0.85, remanent magnetization: 59.5 emu / g, 0.030 emu Squareness ratio: 0.90, remanent magnetization: 63.0 emu / g, 0.032 emu Squareness ratio: 1.00, residual magnetization: 70.0 emu / g, 0.035 emu

[0047] When the amount of magnetic ink applied is 0.5 mg and barium ferrite powder (theoretical value of saturation magnetization: 40 emu / g) is used as the magnetic powder, the conversion values ​​are as follows: Squareness ratio: 0.40, remanent magnetization: 16.0 emu / g, 0.008 emu Squareness ratio: 0.50, remanent magnetization: 20.0 emu / g, 0.010 emu Squareness ratio: 0.55, remanent magnetization: 22.0 emu / g, 0.011 emu Squareness ratio: 0.60, remanent magnetization: 24.0 emu / g, 0.012 emu Squareness ratio: 0.65, remanent magnetization: 26.0 emu / g, 0.013 emu Squareness ratio: 0.85, remanent magnetization: 34.0 emu / g, 0.017 emu Squareness ratio: 0.90, remanent magnetization: 36.0 emu / g, 0.018 emu Squareness ratio: 1.00, residual magnetization: 40.0 emu / g, 0.020 emu

[0048] The magnetic marker 30 shown in FIG. 2A and the magnetic marker 40 shown in FIG. 2B have the same characteristics as the magnetic marker 20 described above.

[0049] The magnetic marker 30 shown in Figure 2A is, for example, a sheet- or tablet-shaped magnetic marker made from the magnetic ink described above, and is embedded inside the orally administered composition 10. The magnetic marker 30 may be supported on a highly biosafe substrate such as a cellulose film or wafer. In this case, the magnetic marker 30 may be embedded inside the orally administered composition 10 in the form of a laminate including the magnetic marker 30 and the substrate. The magnetic marker 40 shown in Figure 2B is a granular magnetic marker made from the magnetic ink described above, and is dispersed throughout the orally administered composition 10.

[0050] Hereinafter, an orally administered product 1 having a magnetic marker 20 provided on the surface 10s of a composition for oral administration 10 will be described in detail with reference to FIG.

[0051] The surface 10s of the composition for oral administration 10 may be partially exposed from the magnetic marker 20. By providing an exposed portion on the surface 10s, the amount of magnetic marker 20 can be reduced and the content of the active ingredient can be increased. Note that by setting the squareness ratio of the magnetic marker 20 to 0.40 or more, even if the amount of magnetic marker 20 is reduced, it is possible to detect it with a magnetic sensor (TMR element).

[0052] The magnetic powder contained in the magnetic marker 20 may contain, for example, one or more types selected from the group consisting of magnetite, maghemite, and barium ferrite. These magnetic powders can be used to form a magnetic marker 20 with a high squareness ratio by using the method described below. Magnetite and maghemite are preferred because they have been confirmed to be relatively safe for living organisms, and maghemite and barium ferrite are advantageous in that they can improve the squareness ratio of the magnetic marker 20.

[0053] The binder contained in the magnetic marker 20 preferably contains one or more resins selected from the group consisting of vinyl resins, vinyl chloride resins, cellulose resins, urethane resins, epoxy resins, acrylic resins, and EB-curable resins. These resins are suitable as binders for the magnetic marker 20 because they have good stability when mixed with magnetic powder and do not inhibit the magnetic properties of the magnetic powder. Specific compounds suitable for the binder include hydroxypropyl cellulose (HPC-SL), a cellulose resin; polyvinylpyrrolidone, a vinyl resin; and ammonioalkyl methacrylate copolymer, an acrylic resin.

[0054] Examples of orally administered substances 1 that are the subject of this embodiment include pharmaceuticals, health foods, functional foods, nutritional supplements, supplements, health-promoting foods, foods for specified health uses, nutritionally functional foods, and foods with functional claims.

[0055] <Methods for producing orally administered products> The following describes methods for producing orally administered products 1 to 3. The first method is a method for producing orally administered product 1 shown in Figure 1, the second method is a method for producing orally administered product 2 shown in Figure 2A, and the third method is a method for producing orally administered product 3 shown in Figure 2B.

[0056] 1 is a method for producing an orally administered product 1 having a magnetic marker 20 on the surface 10s of an orally administered composition 10, and includes the steps of: preparing a composition for oral administration; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring the mixture at a peripheral speed of 4 m / s to 12 m / s for 1 hour or more, and then removing the beads to prepare magnetic ink; and forming a magnetic marker on the surface of the orally administered composition using the magnetic ink, the magnetic marker forming step including applying the magnetic ink to the surface of the orally administered composition, drying the applied magnetic ink, and applying a magnetic field to the magnetic ink during or after drying. Each step is described in detail below.

[0057] (Step of Preparing Orally Administered Composition 10) An orally administered composition 10 is prepared for providing the magnetic marker 20. An already manufactured orally administered composition 10 may be obtained, or an orally administered composition 10 containing an active ingredient and optional additives that exert the desired effect may be manufactured. The dosage form of the orally administered composition 10 is preferably a tablet or capsule. When manufacturing the orally administered composition 10, the manufacturing method is not particularly limited, and known methods can be used as appropriate.

[0058] (Step of Preparing Magnetic Ink) Magnetic powder, binder, dispersion medium, and beads are loaded into a bead mill and stirred to obtain a slurry. The beads are then removed from the slurry using a filter or the like. This yields a magnetic ink containing magnetic powder, binder, and dispersion medium.

[0059] In an embodiment of the present invention, a predetermined material is thoroughly stirred in a bead mill to disperse magnetic powder, which tends to aggregate in a dispersion medium. This suppresses aggregation of the magnetic powder within the magnetic ink. Such magnetic ink has high magnetic properties and can form a magnetic marker 20 with a squareness ratio of 0.40 or more. To achieve sufficient stirring, the stirring speed is set to a peripheral speed of 4 m / s or more and the stirring time is set to 1 hour or more. However, if the stirring speed is too fast, the magnetic powder will be damaged, which may actually reduce the squareness ratio of the magnetic marker 20. Therefore, the stirring speed is set to 12 m / s or less. The stirring speed is preferably set to 6 m / s or more and 10 m / s or less. While there is no particular upper limit to the stirring time, stirring for more than 5 hours results in little improvement in the dispersion effect of the magnetic powder, so it is preferable to set it to 5 hours or less.

[0060] The magnetic ink may further contain at least one of a plasticizer and a dispersant. The inclusion of a plasticizer has the effect of delaying the drying of the magnetic ink and making it easier to maintain a slurry state. In addition, both the plasticizer and the dispersant have the effect of improving the dispersion stability of the materials contained in the magnetic ink (especially the magnetic powder) and suppressing aggregation of the magnetic powder. The plasticizer and the dispersant can be charged into a bead mill along with other materials.

[0061] The magnetic powder and binder contained in the magnetic ink are preferably those described above.

[0062] The dispersion medium contained in the magnetic ink can be one or more selected from the group consisting of alcohols such as ethanol (EtOH), 1-propanol, 2-propanol (IPA), 1-butanol, 2-butanol, 1-pentanol, 2-methyl-1-propanol, and 3-methyl-1-butanol; organic acids such as formic acid and acetic acid; organic acid esters such as ethyl formate, methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate, n-butyl acetate, and isobutyl acetate; ketones such as acetone, methyl ethyl ketone (MEK), and methyl isobutyl ketone; ethers such as diethyl ether and t-butyl methyl ether; saturated carbides such as pentane and heptane; aromatic compounds such as anisole and cumene; dimethyl sulfoxide; and tetrahydrofuran.

[0063] The plasticizer contained in the magnetic ink may be a known pharmaceutical additive, such as one or more selected from the group consisting of propylene glycol (PG), polysorbate, and triethyl citrate.

[0064] The dispersant contained in the magnetic ink may be a known pharmaceutical additive, such as stearic acid.

[0065] If the bead content filled during the manufacturing of the magnetic ink is within an appropriate range, the stirring effect is improved, and magnetic ink suitable for forming a magnetic marker 20 with a high squareness ratio is obtained. The bead content calculated by the following formula (1) is preferably 55.00 vol% or more and 80.00 vol% or less. The bead content is more preferably 64.00 vol% or more and 79.00 vol% or less, more preferably 69.00 vol% or more and 73.00 vol% or less, and particularly preferably 70.00 vol% or more and 73.00 vol% or less. Bead content (volume %) = V ｂｅａｄｓ / (V ｄｉｓ-ｍ +V ｂｅａｄｓ ) × 100 (1) where, V ｂｅａｄｓ is the amount of beads (L) packed in the bead mill, and V ｄｉｓ-ｍ is the amount of dispersion medium (L) filled in the bead mill.

[0066] When manufacturing magnetic ink, if the contents of various materials are appropriate, the viscosity of the magnetic ink, the concentration of the magnetic powder, etc., fall within the appropriate range, improving the stirring effect and resulting in a magnetic ink suitable for forming a magnetic marker 20 with a high squareness ratio. The binder content is preferably 1.00% by mass or more and 14.00% by mass or less, more preferably 2.0% by mass or more and 9.0% by mass or less, and particularly preferably 3.0% by mass or more and 5.0% by mass or less. The magnetic powder content is preferably 10.00% by mass or more and 50.00% by mass or less, more preferably 15.00% by mass or more and 45.00% by mass or less, and particularly preferably 20.00% by mass or more and 40.00% by mass or less. The dispersion medium content is preferably 40.00% by mass or more and 80.00% by mass or less. The plasticizer content is preferably 0% by mass or more and 10.00% by mass or less. The content of the dispersant is preferably 0% by mass or more and 3.00% by mass or less.

[0067] The content of each material can be calculated using the following formulas (2) to (6). These formulas allow the content (mass %) of each material to be calculated when the total mass of the materials filled in the bead mill, excluding the beads, is taken as 100 mass %. Note that plasticizers and dispersants are optional additions and may not be included in the magnetic ink. In such cases, enter "0 g". Content (mass %) of magnetic powder = M ｍａｇ / (M ｍａｇ +M ｂｉｎ +M ｄｉｓ-ｍ +M ｐｌａ +M ｄｉｓ ) × 100 (2) Binder content (mass%) = M ｂｉｎ / (M ｍａｇ +M ｂｉｎ +M ｄｉｓ-ｍ +M ｐｌａ +M ｄｉｓ ) x 100 (3) Content of dispersion medium (mass%) = M ｄｉｓ-ｍ / (M ｍａｇ +M ｂｉｎ +M ｄｉｓ-ｍ +M ｐｌａ +M ｄｉｓ ) × 100 (4) Plasticizer content (mass%) = M ｐｌａ / (M ｍａｇ +M ｂｉｎ +M ｄｉｓ-ｍ +M ｐｌａ +M ｄｉｓ ) × 100 (5) Dispersant content (mass%) = M ｄｉｓ / (M ｍａｇ +M ｂｉｎ +M ｄｉｓ-ｍ +M ｐｌａ +M ｄｉｓ ) × 100 (6) where M ｍａｇ is the amount of magnetic powder (g), M ｂｉｎ is the amount of binder (g), M ｄｉｓ-ｍ is the amount of dispersion medium (g), M ｐｌａ is the amount of plasticizer (g), M ｄｉｓ is the amount of dispersant (g).

[0068] The bead mill used for stirring may be either vertical or horizontal. The filling rate of the bead mill calculated by the following formula (7) is, for example, 70.00% by volume or more and 100.00% by volume or less. Within this range, the stirring effect is improved, and a magnetic ink suitable for forming a magnetic marker 20 with a high squareness ratio can be obtained. Filling rate of the bead mill (volume %) = (V ｄｉｓ-ｍ +V ｂｅａｄｓ ) / V ｍａｘ × 100 (7) where V ｂｅａｄｓ is the amount of beads (L) packed in the bead mill, and V ｄｉｓ-ｍ is the amount of dispersion medium (L) filled in the bead mill, and V ｍａｘ is the volume (L) of the stirring vessel of the bead mill.

[0069] (Step of forming magnetic marker 20) The prepared magnetic ink is applied to the surface of the composition for oral administration 10. There are no particular limitations on the method for applying the magnetic ink, and any known application method can be used.

[0070] After applying the magnetic ink to a desired shape, the magnetic ink is dried in an environment where a magnetic field is applied, thereby fixing the magnetic powder in the magnetic ink in a magnetized state. This allows a magnetic marker to be formed on the surface of the composition for oral administration. It is also possible to magnetize the magnetic powder by applying the magnetic ink, drying the magnetic ink without applying a magnetic field, and then applying a magnetic field in the desired direction after drying.

[0071] The direction in which the magnetic field is applied is not particularly limited, but for example, when an iron oxide-based magnetic material is used, it is preferable to apply the magnetic field in any direction in a plane approximately parallel to the surface of the composition for oral administration (in a plane parallel to the plane of the paper in Figure 1) rather than in a direction perpendicular to the surface of the composition for oral administration (in a direction perpendicular to the plane of the paper in Figure 1), as shown in Figure 1. Known methods such as magnetization treatment with a permanent magnet or magnetization treatment in an electromagnetic field can be used to apply the magnetic field.

[0072] There are no particular limitations on the method for drying the magnetic ink, but drying at high temperatures can cause the drugs to denature and the binder in the magnetic ink to disappear, so it is preferable to dry it using a low-temperature (e.g., 100°C or below) dryer or at room temperature under vacuum.

[0073] Through these steps, the magnetic marker 20 is formed on the surface of the composition for oral administration 10 .

[0074] <Magnetic Ink> The magnetic ink according to this embodiment is prepared by the method described above. The magnetic material composition (corresponding to the magnetic marker for orally administered products) obtained by drying this magnetic ink under a magnetic field, or the magnetic material composition obtained by drying the magnetic ink and then applying a magnetic field, has a squareness ratio of 0.40 or greater. As described above, the magnetic ink according to this embodiment can produce a magnetic marker 20 with a squareness ratio higher than conventional magnetic markers. Therefore, depending on the type of magnetic powder used in the magnetic ink, a magnetic marker 20 with a squareness ratio of 0.40 or greater can be produced even without applying a magnetic field during drying of the magnetic ink. Furthermore, the magnetic material composition does not need to be formed on the surface of the orally administered product; for example, the magnetic material composition may be formed on the surface of a glass substrate or the like, and the squareness may be measured after forming the magnetic material composition. This magnetic ink can be used to form the magnetic marker 20 for the orally administered product 1 according to this embodiment.

[0075] [Second Manufacturing Method] The method for manufacturing the orally administered product 2 shown in Figure 2A is a method for manufacturing an orally administered product 2 having a sheet- or tablet-shaped magnetic marker 30 disposed inside an orally administered composition 10, and includes the following steps: preparing a composition powder for forming the orally administered composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / s to 12 m / s for at least one hour, and then removing the beads to prepare a magnetic ink; producing a sheet- or tablet-shaped magnetic marker from the magnetic ink; and positioning the magnetic marker inside the composition powder and compressing it to obtain an orally administered product. Each step is described in detail below. Note that steps similar to those described in the "first manufacturing method" above will be omitted as appropriate.

[0076] (Step of Preparing Composition Powder) A composition powder for forming the composition 10 for oral administration is prepared. An already produced composition powder may be obtained, or a composition powder containing an active ingredient and optional additives that exhibit the desired effect may be produced. The composition powder preferably has physical properties (particle size, flowability, etc.) that are suitable for compression molding. When producing a composition powder, the production method is not particularly limited, and known methods can be used as appropriate.

[0077] (Step of Preparing Magnetic Ink) This step is the same as the "step of preparing magnetic ink" in the "first manufacturing method" described above, and therefore description thereof will be omitted.

[0078] (Process for Producing Magnetic Marker 30) Magnetic ink is applied to a substrate such as a glass substrate and dried to produce a sheet-like magnetic marker 30. Alternatively, magnetic ink is applied thickly and dried to produce a tablet-like magnetic marker 30. The magnetic marker 30 is then peeled off from the substrate. In the process for producing the magnetic marker 30, a magnetic field is applied during or after the applied magnetic ink has dried. When applying a magnetic field after the magnetic ink has dried, the magnetic field may be applied before or after the dried magnetic ink has been peeled off from the substrate. Instead of producing the magnetic marker 30 on a glass substrate, magnetic ink may be applied to a substrate with high biosafety, such as a cellulose film or wafer, and then dried to produce a sheet-like or tablet-like magnetic marker 30. In this case, the magnetic marker 30 may be used in the subsequent "process for obtaining an orally administered product 2" as a laminate of the substrate and magnetic marker 30 without being peeled off from the substrate.

[0079] (Step of Obtaining Orally-Administered Product 2) The obtained sheet-like or tablet-like magnetic marker 30 is placed inside the composition powder and compressed. The composition powder can be compressed using a known tablet press (for example, JP 2022-179363 A).

[0080] The process for producing the orally administered product 2 using a tablet press is described below. The tablet press includes a die hole and an upper punch and a lower punch arranged above and below the die hole. First, the die hole into which the tip of the lower punch is inserted is filled with a composition powder. The amount of composition powder filled at this time is a portion of the amount necessary to form the orally administered product 2. Next, a magnetic marker 30 (or a laminate of a substrate and a magnetic marker 30) is supplied to the die hole. The die hole is then filled with a composition powder. The amount of composition powder filled at this time is a portion of the amount necessary to form the orally administered product 2, and is adjusted so that the total amount, including the amount of composition powder previously filled, is the amount necessary to form the orally administered product 2. Then, the tip of the upper punch is inserted into the die hole from above, and the composition powder in the die hole is compressed between the tip of the upper punch and the tip of the lower punch. Compression may be performed twice: pre-compression and main compression.

[0081] In this way, an oral dosage form 2 with a magnetic marker 30 therein can be obtained.

[0082] [Third Manufacturing Method] The method for manufacturing the orally administered product 3 shown in Figure 2B is a method for manufacturing an orally administered product 3 in which granular magnetic markers 40 are dispersed throughout the orally administered composition 10, and includes the following steps: preparing a composition powder for forming the orally administered composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / s to 12 m / s for at least one hour, and then removing the beads to prepare a magnetic ink; producing granular magnetic markers from the magnetic ink; mixing the composition powder and the magnetic marker to obtain a mixed powder; and compressing the mixed powder to obtain an orally administered product. Each step is described in detail below. Note that steps similar to those described in the "First Manufacturing Method" or "Second Manufacturing Method" above will be omitted as appropriate.

[0083] (Step of Preparing Composition Powder) This step is the same as the "step of preparing composition powder" in the "Second Production Method" described above, and therefore description thereof will be omitted.

[0084] (Step of Preparing Magnetic Ink) This step is the same as the "step of preparing magnetic ink" in the "first manufacturing method" described above, and therefore description thereof will be omitted.

[0085] (Process for producing magnetic marker 40) The magnetic ink is dried in a fine particle state using a known technique such as spray drying to produce granular magnetic marker 40. In the process for producing magnetic marker 40, a magnetic field is applied while the magnetic ink is drying, or after drying, to the resulting granular magnetic ink. When a magnetic field is applied after the granular magnetic ink has dried, the magnetic field is typically applied before the process for obtaining the mixed powder. However, instead, the magnetic field may be applied during the process for obtaining the mixed powder, during the process for obtaining the orally administered product 3, or after the process for obtaining the orally administered product 3.

[0086] (Step of Obtaining Mixed Powder) The composition powder obtained in the above step and the magnetic marker are mixed in a known mixer such as a blender to obtain a mixed powder.

[0087] (Step of Obtaining Orally-Administered Composition 3) The resulting mixed powder is compressed to obtain an orally-administered composition. As in the "step of obtaining orally-administered composition 2" in the "second production method," a known tablet press can be used to compress the composition powder.

[0088] The process for producing the orally administered product 3 using a tablet press is described below. The mixed powder is filled into the die hole into which the tip of the lower punch is inserted. The amount of mixed powder filled at this time is the entire amount necessary to form the orally administered product 3. The tip of the upper punch is then inserted into the die hole from above, and the mixed powder in the die hole is compressed between the tip of the upper punch and the tip of the lower punch. Compression may be performed twice: pre-compression and main compression.

[0089] In this manner, an oral dosage form 3 can be obtained in which the magnetic markers 40 are dispersed throughout the oral dosage composition 10.

[0090] Example 1 (Preparation of Measurement Samples) First, a magnetic ink was prepared. Using a bead mill (Easy Nano RMB II type, manufactured by Imex Co., Ltd.) with a container volume of 120 mL, magnetic ink was prepared under the conditions of the blending amounts of each material, packing ratio, bead content, stirring speed, and stirring time listed in Tables 1 to 6. The obtained magnetic ink was applied to a 1 cm square glass substrate (Tempax) using a film applicator (film thickness 100 μm). After application of the magnetic ink, magnetic orientation was performed using an electromagnet (ultra-low residual magnetic field leakage magnetic field type electromagnet, manufactured by Toei Scientific Industry Co., Ltd.) before the magnetic ink dried, and the applied film was dried in an applied magnetic field environment, yielding a film-like magnetic material composition.

[0091] The glass substrate on which the magnetic material composition was formed was subjected to magnetization measurement in the orientation direction using a vibrating sample magnetometer (VSM-5 model, manufactured by Toei Kogyo Co., Ltd.) The squareness ratios calculated from the measurement results are shown in Tables 2, 4 and 6.

[0092]

[0093]

[0094]

[0095]

[0096]

[0097]

[0098] The measurement results will be examined. In Experiments Nos. 1 to 5 and 7 to 11, magnetic inks were prepared according to the preparation conditions described in the embodiments of the present invention, and the squareness ratio of the magnetic material compositions made from the obtained magnetic inks was 0.40 or higher. On the other hand, in Experiment No. 6, the magnetite powder itself was used, and the prescribed stirring was not performed, so the squareness ratio was low.

[0099] Using the magnetic ink obtained in Experiment No. 1, magnetic material compositions were prepared under different conditions for applying a magnetic field during drying (with or without application of a magnetic field), and the squareness ratio was measured. The magnetic material composition obtained by drying the magnetic ink in an environment where a magnetic field was applied had a squareness ratio of 0.68 (see Table 2), while the magnetic material composition obtained by drying the magnetic ink without application of a magnetic field had a squareness ratio of 0.62 (not shown in Table 2). This confirmed a tendency for the squareness ratio to increase by drying the magnetic ink in an environment where a magnetic field was applied.

[0100] Example 2 (Preparation of Orally Administered Product Samples) A ​​number of placebo tablets (8.1 mm in diameter, 3.4 mm in thickness) were prepared, and dots were drawn on their surfaces using a handheld dispenser. The dots were drawn based on the arrangement of dots 201 shown in Figures 1a to 1e. The magnetic ink used to draw the dots was that prepared in Experiment No. 9. Before the magnetic ink on the surface of the placebo tablets dried, the placebo tablets were subjected to magnetic orientation using an electromagnet (Toei Scientific Industry Co., Ltd., ultra-low residual magnetic leakage magnetic field type electromagnet), and the magnetic ink was dried in an applied magnetic field. This resulted in oral administration samples with magnetic markers that had been magnetically oriented. For some placebo tablets, dots were drawn with magnetic ink, and then the magnetic ink was dried without being subjected to magnetic orientation. This resulted in oral administration samples with magnetic markers that had not been magnetically oriented. Figure 3 shows photographs of the prepared oral administration samples (samples a1 to e1, a2 to e2).

[0101] For samples a1 to e1 and a2, magnetization measurements were performed in the magnetic field orientation direction using a vibrating sample magnetometer (VSM-5 model, manufactured by Toei Kogyo Co., Ltd.). The squareness ratios calculated from the measurement results are shown in Table 7.

[0102]

[0103] All of the orally administered samples had a squareness ratio of 0.40 or more. In particular, sample b1, in which five dots were connected in one direction, and sample e1, in which three dots were connected in one direction, showed a tendency for the squareness ratio of the samples to improve.

[0104] Example 3 The effects of the magnetic powder content, bead content, and binder content when preparing a magnetic ink on the squareness ratio of the resulting magnetic ink were investigated. Figures 4A to 4C, 5A to 5C, and 6A to 6C are graphs in which the squareness ratio of a film-shaped magnetic material composition prepared from a magnetic ink prepared under the conditions listed in Table 8 is plotted against the content of each component contained in the magnetic ink. The film-shaped magnetic material composition was prepared using the method described in Example 1. Note that the preparation conditions for the magnetic ink, unless otherwise specified, were the same as those for the magnetic ink in Experiment No. 1.

[0105]

[0106] 4A to 4C are graphs showing the change in squareness ratio of magnetic material compositions prepared from magnetic inks when the content of magnetic powder contained in the magnetic ink was varied. As can be seen from the graphs in FIGS. 4A and 4C, when stirring was performed using beads with a diameter of 0.2 mm, the squareness ratio was maximized when the content of magnetic powder was approximately 30% by mass. As can be seen from the graph in FIG. 4B, when stirring was performed using beads with a diameter of 0.5 mm, a tendency for the squareness ratio to increase with increasing magnetic powder content was confirmed up to a magnetic powder content of 40% by mass. Furthermore, for both bead diameters of 0.2 mm and 0.5 mm, the squareness ratio was high, at 0.65 or higher, when the content of magnetic powder was in the range of 20.00% to 40.00% by mass.

[0107] 5A to 5C are graphs showing the change in squareness of the magnetic material composition produced from the magnetic ink when the bead content during stirring in a bead mill is varied. As can be seen from the graphs in FIGS. 5A and 5C, when stirring was performed using beads with a diameter of 0.2 mm, the squareness ratio was maximized when the bead content was approximately 71% by volume. As can be seen from the graph in FIG. 5B, when stirring was performed using beads with a diameter of 0.5 mm, the squareness ratio was maximized when the bead content was approximately 72% by volume. Furthermore, for both the 0.2 mm and 0.5 mm bead diameters, the squareness ratio was high, at 0.65 or higher, when the bead content was in the range of 70.00% to 73.00% by volume.

[0108] 6A to 6C are graphs showing the change in squareness of the magnetic material composition produced from the resulting magnetic ink when the binder content in the magnetic ink was varied. As can be seen from the graphs in FIGS. 6A and 6C, when stirring was performed using beads with a diameter of 0.2 mm, the squareness ratio was maximized when the binder content was approximately 7% by mass. As can be seen from the graph in FIG. 6B, when stirring was performed using beads with a diameter of 0.5 mm, the squareness ratio was maximized when the binder content was approximately 5% by mass. Furthermore, for both the 0.2 mm and 0.5 mm bead diameters, the squareness ratio was high, at 0.65 or higher, when the binder content was in the range of 3.0% to 5.0% by mass.

[0109] This application claims priority based on Japanese Patent Application No. 2024-082143, filed on May 20, 2024, the entire contents of which are incorporated herein by reference.

[0110] 1, 2, 3 Orally administered substance 10 Orally administered composition 10s Surface of orally administered composition 10e Exposed portion 20, 30, 40 Magnetic marker 201 Dot

Claims

1. An orally administered product comprising a composition for oral administration and a magnetic marker attached to the composition for oral administration, wherein the magnetic marker comprises magnetic powder and a binder and has a squareness ratio of 0.40 or more.

2. The oral dosage form of claim 1, wherein the squareness ratio of the magnetic marker is 0.50 or greater.

3. The oral dosage form of claim 1, wherein the squareness ratio of the magnetic marker is 0.55 or greater.

4. The oral dosage form of claim 1, wherein the squareness ratio of the magnetic marker is 0.60 or greater.

5. The oral dosage form of claim 1, wherein the squareness ratio of the magnetic marker is 0.65 or greater.

6. The oral dosage form according to any one of claims 1 to 5, wherein the magnetic marker is provided on the surface of the oral dosage composition.

7. The oral dosage form according to any one of claims 1 to 6, which is a tablet or capsule.

8. The oral dosage form according to any one of claims 1 to 7, wherein the magnetic powder comprises one or more selected from the group consisting of magnetite, maghemite, and barium ferrite.

9. The oral administration preparation according to any one of claims 1 to 8, wherein the binder comprises one or more selected from the group consisting of vinyl resins, vinyl chloride resins, cellulose resins, urethane resins, epoxy resins, acrylic resins, and EB-curable resins.

10. A method for manufacturing an orally administered substance, comprising the steps of: preparing a composition for oral administration; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / s to 12 m / s for 1 hour or more, and then removing the beads to prepare magnetic ink; and using the magnetic ink to form a magnetic marker on the surface of the composition for oral administration, the magnetic marker forming step comprising applying the magnetic ink to the surface of the composition for oral administration, drying the applied magnetic ink, and applying a magnetic field to the magnetic ink during or after drying.

11. A method for producing an oral administration product, comprising the steps of: preparing a composition powder for forming an oral administration composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / s to 12 m / s for 1 hour or more, and then removing the beads to prepare a magnetic ink; producing a sheet- or tablet-shaped magnetic marker from the magnetic ink; and arranging the magnetic marker inside the composition powder and compressing it to obtain an oral administration product.

12. A method for producing an oral administration product, comprising the steps of: preparing a composition powder for forming an oral administration composition; filling a bead mill with magnetic powder, a binder, a dispersion medium, and beads, stirring at a peripheral speed of 4 m / s to 12 m / s for 1 hour or more, and then removing the beads to prepare a magnetic ink; producing granular magnetic markers from the magnetic ink; mixing the composition powder and the magnetic markers to obtain a mixed powder; and compressing the mixed powder to obtain an oral administration product.

13. In the step of preparing the magnetic ink, the amount of beads to be filled V ｂｅａｄｓ (L) and the amount of dispersion medium V ｄｉｓ-ｍ The method for producing an oral administration product according to any one of claims 10 to 12, wherein the bead content is 55.00 vol% or more and 80.00 vol% or less when the total of (L) is 100 vol%.

14. The method for producing an oral dosage form according to any one of claims 10 to 13, wherein in the step of preparing the magnetic ink, at least one of a plasticizer and a dispersant is further charged into the bead mill.

15. A method for producing an oral dosage form according to any one of claims 10 to 14, wherein in the step of preparing the magnetic ink, when the total mass of the materials filled into the bead mill excluding the beads is taken as 100 mass%, the magnetic powder content is 10.00 mass% or more and 50.00 mass% or less.

16. A method for producing an oral dosage form according to any one of claims 10 to 15, wherein in the step of preparing the magnetic ink, when the total mass of the materials filled into the bead mill excluding the beads is taken as 100 mass%, the binder content is 1.00 mass% or more and 10.00 mass% or less.

17. A method for producing an oral dosage form according to any one of claims 10 to 16, wherein the magnetic powder comprises one or more selected from the group consisting of magnetite, maghemite, and barium ferrite.

18. The method for producing an oral administration product according to any one of claims 10 to 17, wherein the binder comprises one or more selected from the group consisting of vinyl resins, vinyl chloride resins, cellulose resins, urethane resins, epoxy resins, acrylic resins, and EB-curable resins.

19. A magnetic ink comprising a magnetic powder, a binder, and a dispersion medium, wherein the magnetic ink is dried under a magnetic field application environment to produce a magnetic material composition having a squareness ratio of 0.40 or more.

20. A magnetic ink comprising a magnetic powder, a binder, and a dispersion medium, wherein the magnetic ink is dried and then a magnetic field is applied to produce a magnetic material composition having a squareness ratio of 0.40 or more.

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