JP2014110065A - Manufacturing method of a magnetic sheet, application method of magnetic sheet and magnetic sheet - Google Patents

Abstract

An object of the present invention is to obtain a magnetic sheet having a reduced thickness.
A method of manufacturing a magnetic sheet according to the present invention includes a step of forming a magnetic layer 5 on a transfer sheet 1 made of resin, and a surface of the magnetic layer 5 opposite to the surface on which the transfer sheet 1 exists. And a step of attaching the adhesive layer of the double-sided tape having an adhesive layer formed on the release tape 10 and a step of peeling the transfer sheet 1 from the magnetic layer, thereby obtaining a thin magnetic sheet. It is something that can be done.
[Selection] Figure 2

Description

  The present invention relates to a magnetic sheet that generates magnetism or a magnetic sheet that can be magnetized.

  Magnets have long been known to generate magnetism. It has also been known for a long time that there is a magnetic material that can be magnetized by applying a magnetic field.

  Under such circumstances, a flexible magnetic sheet is required, and a method of forming a magnetic layer by applying a magnetic paint on a base sheet is known (see Patent Document 1 and Patent Document 2).

  Such a magnetic sheet can be used as a magnetic scale by magnetizing a magnetic layer. As a specific example of usage, there is a method of detecting the relative position between the magnetic scale and the magnetic sensor by detecting the magnetism from the magnetized magnetic sheet with the magnetic sensor.

JP 2006-114097 A JP 2011-227978 A

  In recent years, electronic devices have been downsized. Under such circumstances, the magnetic sheet is desired to be further reduced in thickness, but the base sheet needs to have a corresponding thickness in consideration of the strength and the like at the time of manufacture, making it difficult to reduce the thickness.

  Of course, it is also possible to use a thin magnetic sheet such as a magnetic tape for audio or a magnetic tape for video. However, magnetic tape is very thin and it is difficult to keep its shape without a support, and there is no problem when it is stored inside a cassette. There are difficulties.

  The present invention solves the above-described conventional problems, and an object thereof is to obtain a magnetic sheet having a reduced thickness.

  In order to achieve the above object, the present invention has the following means.

  The invention according to claim 1 is the step of forming a magnetic layer on a transfer sheet made of a resin, and an adhesive layer is formed on the release tape on the surface of the magnetic layer opposite to the surface on which the transfer sheet exists. A method for producing a magnetic sheet comprising: a step of attaching the adhesive layer of the double-sided tape, and a step of peeling the transfer sheet from the magnetic layer.

  Since the magnetic layer is formed on the transfer sheet made of a resin, the invention according to claim 1 can be easily formed as compared with the case where the magnetic layer is formed on the adhesive layer. By using it as a support, it is easy to handle. In addition, since the adhesive layer is not exposed until it is attached, it can be prevented from being inadvertently attached to an object, and it is easy to handle. By attaching the release sheet at the time of application, the magnetic sheet becomes a magnetic layer. Since it is the thickness of the adhesive layer, it has the effect of being thin.

  In the invention according to claim 2, after the method for manufacturing the magnetic sheet according to claim 1, the release tape of the double-sided tape is peeled from the adhesive layer, and the adhesive layer is attached to a member to be attached. This is a method of using a magnetic sheet for attaching a magnetic sheet to a member to be attached.

  The invention according to claim 2 is excellent in handleability by utilizing the release tape as a support, and further has the effect that it can be thinned because the release tape is peeled off when applied and becomes the thickness of the magnetic layer and the adhesive layer. Have.

  The invention according to claim 3 is a magnetic layer, an adhesive layer provided on one surface of the magnetic layer, a peelable release tape provided on a surface of the adhesive layer facing the magnetic layer, It is a magnetic sheet provided with.

  The invention described in claim 3 has the effect of providing excellent peelability by providing a peelable release tape, and reducing the thickness by peeling the release tape during use.

  As described above, the magnetic sheet manufacturing method of the present invention can obtain a magnetic sheet having a reduced thickness.

Process drawing of the manufacturing method of the magnetic sheet in Embodiment 1 of this invention Process drawing of the manufacturing method of the magnetic sheet in Embodiment 1 of this invention Process drawing of the manufacturing method of the magnetic sheet in Embodiment 1 of this invention The figure which shows the usage method of the magnetic sheet in Embodiment 1 of this invention (A), (b) Process drawing of the manufacturing method of the magnetic sheet in Embodiment 2 of this invention

(Embodiment 1)
Hereinafter, the present invention will be described using the first embodiment.

  1 to 2 are process diagrams of a method for manufacturing a magnetic sheet according to Embodiment 1 of the present invention.

  In FIG. 1, a transfer sheet 1 is a sheet made of a flexible resin, and the material thereof can be, for example, PET (polyethylene terephthalate). The transfer sheet 1 has a smooth surface, and the transfer sheet 1 preferably has good peelability. For this reason, it is preferable not to form an adhesive layer or the like on the surface of the transfer sheet 1. More preferably, peeling is facilitated by a method of forming a water-repellent layer, such as coating the surface of the transfer sheet 1 with a silicon-based material for water-repellent treatment.

  The applicator 2 is an apparatus that applies the paste-like magnetic paint 3 to the transfer sheet 1. Specifically, an apparatus for applying by a doctor blade method is suitable. The magnetic paint 3 is a mixture of a resin and a powdery magnetic material. As the resin, urethane resin or the like can be used. Moreover, a barium ferrite-type material etc. can be used for a magnetic body.

  The dryer 4 dries the magnetic paint 3 to accelerate the hardening of the magnetic paint 3. When the liquid component such as water and solvent contained in the magnetic coating material 3 evaporates or solidifies, the magnetic coating material 3 is cured and becomes the magnetic layer 5.

  The stacked sheet 6 is a flexible sheet, and for example, a sheet made of a resin such as PET can be used. However, it is preferable that the overlapping sheet 6 has moisture permeability. Here, the moisture permeability means a property that does not allow liquid to pass through but allows gas such as moisture to pass through, and the stacked sheet 6 uses a microporous film in which a lot of very fine holes are formed. It is preferable. Such a moisture permeable film is known, for example, as described in JP-A-9-174738.

  In the manufacturing method in FIG. 1, first, an application process is performed in which the transfer sheet 1 is supplied and the coating material 2 applies the magnetic paint 3 to the upper surface of the transfer sheet 1. At this time, the applicator 2 is set so that the magnetic paint 3 is applied with a constant thickness. The thickness varies depending on the application. When detecting magnetism from a magnetic sheet without contacting a magnetic sensor (not shown), when using for so-called non-contact detection, a strong magnetic force is required, so the thickness of the magnetic layer 5 should be 100 μm or more. It seems to be necessary. If it is too thick, the magnetic coating material 3 cannot be formed, so that a thickness of 100 to 200 μm is suitable in practice.

  The magnetic paint 3 becomes solid by the dryer 4 before going to the next step. However, even if it says a solid, it does not become a rigid body, but it is in a state where it is easily plastically deformed when an external force is applied. However, it has been removed from the liquid or paste form. When the magnetic coating material 3 is further cured, it becomes a state close to a rigid body, or although it is an elastic body having flexibility, it becomes difficult to cause plastic deformation, but at this stage, it is not cured so much. In that respect, it can be said that it is semi-cured because it is not completely cured. When the time until the next step is long or when a short time is required for solidification depending on the conditions such as the atmospheric temperature, it may be naturally dried. Note that the magnetic paint 3 is set so as to be positioned vertically above the transfer sheet 1 until the magnetic paint 3 is solidified.

  Next, a superposition process is performed in which the superposed sheet 6 is superposed on the solid magnetic layer 5. As a result, the magnetic paint 3 is sandwiched between the transfer sheet 1 and the overlap sheet 6. Specifically, the superposition is performed such that the superposition sheet 7 is pressed against the magnetic layer 5 on the transfer sheet 1 by the superposition rollers 7 and 20.

  In a state where the transfer sheet 1, the magnetic layer 5, and the overlap sheet 6 are overlapped, the sheet is once wound up in a roll shape. This wound sheet is a sheet roll 8. When winding, the roller 21 can be wound without being loosened by winding the roller 21 against the sheet roll 8.

  When the sheet roll 8 is wound, naturally, a certain tension is applied. As a result, the transfer sheet 1, the magnetic layer 5, and the stacked sheet 6 positioned inside the sheet roll 8 receive pressure in the thickness direction. It becomes a state. By storing for a while in a state where pressure is applied in this way, the magnetic layer 5 is compressed and contracts in the thickness direction. This state is maintained until the magnetic layer 5 is completely cured. By being compressed, the density of a magnetic body (not shown) in the magnetic layer 5 can be increased, and the magnetic characteristics can be improved.

  Next, as shown in FIG. 2, the transfer sheet 1, the magnetic layer 5, and the stacked sheet 6 are pulled out from the sheet roll 8. At this time, it is possible to prevent the sheet roll 8 from being slack by pressing the roller 22 against the sheet roll 8.

  Next, the peeling process which peels the lamination sheet 6 from the magnetic layer 5 is performed. At this time, it is preferable that the overlap sheet 6 be easily separated from the magnetic layer 5. For this purpose, for example, there is a method of forming a release layer in advance on the overlap sheet 6. Further, the overlap sheet 6 can be separated by being placed along the separation roller 9. The roller 23, together with the separation roller 9, sandwiches the transfer sheet 1, the magnetic layer 5, and the overlapping sheet 6 and promotes their smooth movement.

  Next, the process of superimposing the peeling tape 10 in which the adhesion layer 11 was formed on the magnetic layer 5 is performed. Here, PET can be used for the peeling tape 10. The adhesive layer 11 can be the same adhesive layer used for adhesive tapes, double-sided tapes, and the like. A double-sided tape is constituted by the release tape 10 and the adhesive layer 11. The transfer sheet 1, the magnetic layer 5, the peeling tape 10, and the adhesive layer 11 are sandwiched between the superimposing roller 12 and the roller 24 so that they are superposed and the adhesive layer 11 is adhered to the magnetic layer 5.

  Next, the transfer sheet 1 is peeled off. At this time, the transfer sheet 1 is peeled from the magnetic layer 5 by the separation roller 13 and the roller 25. By this step, a magnetic sheet composed of the magnetic layer 5, the adhesive layer 11, and the release tape 10 can be obtained.

  FIG. 3 is a diagram showing a manufacturing method according to an embodiment of the present invention. More specifically, the magnetization process is shown. The magnetic sheet 30 is a magnetic sheet obtained from FIGS. 1 and 2. The magnetic sheet 30 shown in FIG. 3 is cut to an appropriate length from the state shown in FIG. 2 in consideration of handleability, but the state shown in FIG. It doesn't matter. The magnetic layer 5 of the magnetic sheet 30 is magnetized by the magnetizing head 31. The magnetic layer 5 can be magnetized by periodically generating a magnetic field while moving the magnetizing head 31 relative to the magnetic sheet 30. If the magnetic sheet 30 does not need to be magnetized, the process shown in FIG. 3 is not necessary.

  FIG. 4 is a diagram showing a usage method in an embodiment of the present invention. The magnetic sheet 30 is the one from which the release tape 10 is peeled off. The peeling method of this peeling tape 10 can be performed by hand similarly to the peeling method of the peeling paper of a general double-sided tape. Since the adhesive layer 11 is exposed on the magnetic sheet 30 from which the release tape 10 has been peeled off, the magnetic sheet 30 is attached to the adherend member 32 by bringing the adhesive layer 11 into contact with the adherend member 32. Yes.

  When the magnetic sheet is manufactured through the above-described steps, the following effects can be obtained.

  As a first effect, since the magnetic layer 5 is formed by applying the magnetic paint 3 on the transfer sheet 1 made of a resin, it is possible to easily form a magnetic layer having a uniform thickness by a doctor blade method or the like. Even if the magnetic layer 3 is formed by applying the magnetic paint 3 on the adhesive layer 11, it is difficult to form a magnetic layer having a uniform thickness by the adhesive force of the adhesive layer 11.

  As a second effect, the magnetic sheet 30 can be only the adhesive layer 11 and the magnetic layer 5 immediately before being attached to the member 32 to be attached. The magnetic layer 5 is always the transfer sheet 1, Since it is supported by the overlap sheet 6 or the release tape 10, it is excellent in handleability during production or transportation.

  As a third effect, since the magnetic layer 5 is sandwiched between the transfer sheet 1 and the overlap sheet 6 during the manufacturing process, the magnetic layer 5 can be firmly held. Since both the transfer sheet 1 and the overlapping sheet 6 are separated from the magnetic layer 5 in a later step, the magnetic layer 5 cannot be bonded. Accordingly, while the magnetic layer 5 is formed on the transfer sheet 1, the magnetic layer 5 may be peeled off during the manufacturing process, but this can be prevented by being sandwiched with the overlapping sheet 6.

(Embodiment 2)
5A and 5B show a method for manufacturing a magnetic sheet according to Embodiment 2 of the present invention. The same components as those in the first embodiment are denoted by the same reference numerals. The difference from the magnetic sheet manufacturing method according to the first embodiment is that the stacked sheet 6 is not used. Along with this difference, the step of superimposing the superposed sheet 6 on the magnetic layer 5 in Embodiment 1 and the step of separating the superposed sheet 6 from the magnetic layer 5 are eliminated.

  After the step shown in FIG. 5, the step shown in FIG. 3 in Embodiment Mode 1 and the usage method shown in FIG. 4 can be performed.

  In the second embodiment, it is preferable that both surfaces of the transfer sheet 1 are subjected to water repellent treatment such as coding with a silicon-based material so that the magnetic layer 5 is easily peeled off. This is to prevent the magnetic layer 5 from coming into contact with both surfaces of the transfer sheet 1 when the sheet roll 8 is formed, but the magnetic layer 5 and the overlap sheet 6 are not easily separated.

  In addition, when making it into the sheet roll 8, it is good to wind up so that the magnetic layer 5 may become inside. This is to prevent the magnetic layer 5 from being exposed for a long time and adhering dust or the like.

  Unlike the first embodiment, since the magnetic layer 5 is not sandwiched between the transfer sheet 1 and the overlapping sheet 6, it is preferable to form the sheet roll 8 in an early time after the magnetic paint 3 is semi-dried.

  The magnetic sheet manufactured in this way can obtain the same effects as the first effect and the second effect of the first embodiment.

  In the first and second embodiments, the magnetic layer 5 may be completely cured while being dried in the state of the sheet roll 8, but the magnetic layer 5 and the laminated sheet 6 are again straightened from the sheet roll 8. It can also be performed in a state where it is stretched. Alternatively, the stacked sheet 6 may be completely cured after being peeled off.

  And once it is stored in the state of the sheet roll 8, the magnetic layer 5 and the overlap sheet 6 are pulled out again to peel off the overlap sheet 6, but without being in the state of the sheet roll 8, The peeling step may be continuously performed after the magnetic coating material 3 is dried.

  Moreover, although the magnetic layer 5 is compressed by making it the state of the sheet roll 8, you may compress using a roller for compression separately.

  The method for producing a magnetic sheet and the magnetic sheet according to the present invention can be applied to an electronic device or the like.

DESCRIPTION OF SYMBOLS 1 Transfer sheet 2 Coating machine 3 Magnetic coating material 4 Dryer 5 Magnetic layer 6 Overlay sheet 7 Overlay roller 8 Sheet roll 9 Separating roller 10 Release tape 11 Adhesive layer 12 Overlay roller 13 Separation roller 20 Roller 21 Roller 22 Roller 23 Roller 24 Roller 25 Roller 30 Magnetic sheet 31 Magnetic head 32 Member to be adhered

Claims (3)

Forming a magnetic layer on a resin transfer sheet;
Attaching the adhesive layer of the double-sided tape in which an adhesive layer is formed on a release tape to the surface of the magnetic layer opposite to the surface on which the transfer sheet exists;
Peeling the transfer sheet from the magnetic layer;
The manufacturing method of the magnetic sheet provided with this. After the method for manufacturing a magnetic sheet according to claim 1, the magnetic tape is attached to the member to be attached by peeling the release tape of the double-sided tape from the adhesive layer and attaching the adhesive layer to the member to be attached. How to use the magnetic sheet. A magnetic layer;
An adhesive layer provided on one surface of the magnetic layer;
A peelable release tape provided on a surface of the adhesive layer facing the magnetic layer;
Magnetic sheet with

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