JPH04367666A - Thick-film magnetic composition and production thereof and magnetic treating device formed by using thick-film magnetic composition - Google Patents

Abstract

PURPOSE:To prevent the degradation in the intensity of holding magnetic fields while deceasing magnet-constituting materials by forming a ferromagnetic material so as to constitute doughnut-shaped thick films on a nonmagnetic base plate and magnetizing these thick films, thereby forming doughnut-shaped thick-film magnets. CONSTITUTION:A proper amt. of Carbitol is added as a solvent to ferromagnetic material powder; for example, samarium cobalt which is SmCo5 in basic constitution, and a thermosetting silicon coating material and these powders are mixed to prepare magnetic paste. The silicon base-plate 2 printed with thick-film magnetic paste patterns having the doughnut shape blanked in the central part 3 by using such paste is heated in an atmosphere kept at 180 deg.C and is thereby subjected to a thermosetting treatment for the magnetic material, by which the approximately circular thick-film magnetic compsns. 1 are formed. The doughnut-shaped magnetic material thick films thermoset or dried in such a manner are magnetized to form the magnets. The thick-film magnets with which desired magnetic characteristics are obtainable and the magnetic treating device formed by using such magnets are obtd. with the lesser materials.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a donut-shaped thick film magnetic composition with a hollow center and a magnetic therapy device using the thick film magnetic composition.

0002

BACKGROUND OF THE INVENTION Conventional magnetic therapy devices that utilize magnetic effects use magnets in which a ferromagnetic material is formed into, for example, a circular thick film shape and magnetized.

0003

However, as shown in FIG. 6, the magnetic field strength distribution of a magnetized magnet is strongest at the periphery and weakest at the center. For example, in the case of a thick film magnet made of Ba ferrite with a thickness of 1 mm and a diameter of 6 mm, the center part has a
Gauss, while the peripheral area is 200 Gauss. For this reason, it has good performance as a ferromagnetic material that constitutes a magnet.
No expensive materials could be used.

0004

[Means for Solving the Problems] The present invention has been made for the purpose of solving the above-mentioned problems, and has the following configuration as a means for solving the above-mentioned problems. That is, a ferromagnetic material is mixed with a thermosetting resin on a non-magnetic substrate to form a donut-shaped thick film magnetic material with a hollow center, and magnetized after heating and curing.

[0005] Furthermore, the thick film magnet magnetized as described above is formed to match the treatment area to form a magnetic therapy device.

[0006]

[Function] With the above structure, a thick film magnetic composition can be produced with a small number of steps, with a minimum investment in equipment since the steps are substantially the same as those for pattern printing, and which can be applied to shape changes at a minimum cost. Furthermore, since the thick film magnet is donut-shaped, it is possible to provide a thick film magnet that can obtain desired magnetic properties with a small amount of material, and a magnetic therapy device using the magnet.

[0007] This means that even expensive magnetic materials can be used, and thick film magnetic compositions and magnetic therapy devices that can achieve low cost and high effectiveness can be provided.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings.

[0009]

FIRST EXAMPLE FIG. 1 is a process diagram showing the manufacturing process of a thick film magnetic composition according to an example of the present invention. Hereinafter, an outline of the manufacturing process of an embodiment of the present invention will be explained with reference to FIG. The following description will be made using an example in which the thick film magnet of this embodiment is formed on a silicone rubber substrate. However, the present invention is not limited to the case where it is formed on this silicone rubber substrate, and it goes without saying that it can be formed on a substrate made of any material such as a phenol substrate or an epoxy substrate.

First, in step 1, a ferromagnetic material powder, for example, having an average particle size of 2 having the basic composition of (SmCo5) is prepared.
A samarium-cobalt alloy powder of 0 μm to 30 μm and a thermosetting silicone paint are weighed so that the amounts are 81 wt% and 19 wt%, and an appropriate amount of carbitol is added as a solvent. Then, mix this thoroughly using, for example, a three-roll roll to make a magnetic paste.

[0011] This ferromagnetic material powder is not limited to the above example; for example, the basic composition is (Nd2
A neodymium/iron/boron alloy powder having an average particle diameter of 15 μm to 30 μm (Fe14B) and a thermosetting silicone paint may be weighed so that the amounts are 85 wt% and 15 wt%. Further, ferrite powder or the like may be used.

Next, in step 2, the magnetic paste produced in step 1 is used to print a thick film magnetic paste pattern having a desired thickness and a donut-shaped pattern with a hollow center. This printing process can use the same printing equipment as used for printing conductor patterns of electric circuits, etc., and can be performed using the same method. For example, printing can be performed using various printing methods such as silk screen printing, flexographic printing, letterpress printing, and gravure printing. This printing shape can also be any shape, and even if you print just one pattern on the board, multiple patterns of the same shape, or multiple patterns of different shapes, all will be the same. It's only a process.

Next, in step 3, the silicone rubber substrate printed with the thick film magnetic paste is heated for about 30 minutes in an atmosphere of 180°C.
Heat for a minute to perform magnetic thermosetting treatment. An example of a thick film magnetic composition heat-cured in this manner is shown in FIG. Figure 2
An example is shown in which a substantially circular thick film magnetic composition is formed on a substrate. In FIG. 2, 1 is a donut-shaped thick film magnetic composition;
2 is a silicon rubber substrate, and 3 is a central hollow portion. However, the shape of this thick film magnetic material is not limited to this approximately circular shape, and as long as the shape is hollow in the center, it may be approximately square as shown in FIG. 3, or approximately triangular as shown in FIG. Good too. Of course, there may be more polygons.

Note that if the magnetic material is not mixed with a thermosetting resin vehicle material, this thermosetting step may be omitted and the material may be dried in a drying step. In the subsequent step 4, the doughnut-shaped thick film of ferromagnetic material thus thermally cured or dried is magnetized by a magnetizer to form a magnet. For example, as shown in FIG. 5, a silicon rubber substrate on which a thick film magnetic composition is formed is placed in a magnetizing machine in which an N pole is formed on the lower surface and an S pole is formed on the upper surface, and the lines of magnetic force pass through it in the thickness direction. It is magnetized at 15,000 oersted to form a magnetic effect element (magnet). Note that the direction of magnetization is not limited to the above-mentioned thickness direction, and similar effects can be obtained even if the thick film magnetic composition is magnetized in the planar direction. Of course, it is also possible to magnetize in other directions.

As shown in FIG. 6, the magnetic field distribution at the center is very weak, and even if the thick film magnet is shaped like a donut,
There is almost no change in magnetic force. In this case, there are two cases: a circular magnet with an outer circumference of 6 mm, and a case where the outer circumference of the magnet is 6 mm.
A comparison will be made with a substantially circular donut-shaped magnet with an inner circumference of 3 mm and an inner circumference of 3 mm. The area S1 of the circular magnet part when the outer circumference of the magnet is 6 mm is S1 = π (6/2) 2 = 28.26
It becomes mm2. On the other hand, the diameter of the central cutout is 3
The area S2 of the mm part is S2 = π (3/2) 2 = 7
．． 07 mm2, and the difference ΔS in area between the circular magnet and the donut-shaped magnet is ΔS=S1 −S2 =(π/4)・(
36-9)=(π×27)/4.

[0016] Therefore, ΔS/S1 = {(π×27)
/4}/{(π×36)/4}=(3/4),
Since this area ratio is approximately proportional to the amount of magnetic material used, the doughnut-shaped material is approximately (3/4) smaller than the case where the material is a circular magnet, even though the same magnetic flux density is obtained.
can be suppressed to The usage ratio of this material is determined by the hollow area of the central portion, and is preferably optimized within a range that does not cause a decrease in the strength of the magnetic field in accordance with the outer diameter.

As explained above, according to this embodiment, the amount of material can be reduced compared to the conventional circular magnet, and the strength of the magnetic field depends on the amount of thermosetting resin mixed. It can be adjusted by adjusting the strength of the magnetic field during magnetization, making it possible to provide donut-shaped thick film magnets with all specifications. Therefore, it can be applied to all kinds of uses, and is particularly suitable for applications such as magnetic therapy devices and sensors.

When a magnet with a hollow center is used in a magnetic therapy device as in this embodiment, if the thickness of the magnet portion is approximately 1 mm or more, the edges at the periphery also act as an acupressure effect, which improves the treatment. The effect is further improved. In particular, in the case of a substantially circular donut shape, in addition to the outer circumferential edge, the inner circumferential edge also has an acupressure effect, which doubles the acupressure effect. The reason why a thermosetting silicone paint is used as the thermosetting resin is because the substrate material is silicone rubber. When printing magnetic paste on a substrate, epoxy resin may be used to increase the adhesive strength to the substrate. Even when these substrates were used, the same effects as described above were obtained with the epoxy resin.

Furthermore, it can be made of any material as long as it is made of a sheet-like non-magnetic material, and can also be made of a breathable material. Note that the printed pattern shape of the magnetic paste can be any shape, for example, square, rectangular, circular, oval, diamond, trapezoid, triangular, etc., even if the center part of each is hollowed out. It is also very easy to create a polygonal shape with a hole in the center of the polygonal shape.

[0020] Furthermore, the substrate (sheet portion) may be made of a breathable material; in this case, since the central portion is cut out, the breathability of the magnetic element portion is increased, and the sheet does not come into contact with the skin. Even when it is placed in close contact, it is possible to suppress the occurrence of stuffiness, rash, etc. By forming the central portion into a hollow shape in this manner, the amount of magnetic material used can be reduced, which is particularly effective when expensive magnetic materials such as samarium and cobalt are used. That is, when such an expensive magnetic material is used, the material cost can be kept low.

[0021]

[Effects of the Invention] As explained above, according to the present invention, by forming a ferromagnetic material in a donut shape on a substrate, manufacturing costs can be kept low without reducing the strength of the generated magnetic field. . Furthermore, by using a magnetic therapy device that uses donut-shaped thick film magnets, the effect of acupressure can be enhanced. Furthermore, if the magnet-arranged sheet or the like is made of a material that has air permeability, the air permeability of the magnet portion will increase, and the effect of effectively preventing stuffiness and rash can also be obtained.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the manufacturing process of a doughnut-shaped thick film magnet according to an embodiment of the present invention.

FIG. 2 is a diagram showing the state of formation of a donut-shaped thick film magnetic composition in this example.

FIG. 3 is a diagram showing the state of formation of another doughnut-shaped thick film magnetic composition.

FIG. 4 is a diagram showing the state of formation of yet another doughnut-shaped thick film magnetic composition.

FIG. 5 is a diagram for explaining the magnetization process in this example.

FIG. 6 is a diagram for explaining the magnetic field strength distribution in a circular thick film magnet.

[Explanation of symbols]

1 Thick film magnetic composition 2. It is a substrate.

Claims (2)

[Claims] [Claim 1] A ferromagnetic material is mixed with a thermosetting resin on a non-magnetic substrate to form a donut-shaped thick film magnetic material with a hollow center portion, and magnetized after heating and curing. Thick film magnetic composition. [Claim 2] A donut-shaped thick film magnetic material with a hollow center is formed by mixing at least one ferromagnetic material with a thermosetting resin on a non-magnetic substrate, and is magnetized after heating and curing. A magnetic treatment device using a thick film magnetic composition, characterized in that a thick film magnet is formed to match the treatment area.