JP2006307209A - Sheet product, laminated product, product equipped with sheet and method for manufacturing sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sheet product easy to handle, and furthermore a sheet having high performance in addition to good handling properties. <P>SOLUTION: The sheet product 1 is formed by mixing a filler 2 having predetermined properties with a binder 3 and molding the resultant mixture into a sheet, and this sheet product 1 can exhibit the properties which the filler 2 possesses. This sheet product 1 has tackiness on the surface site of one side in the thickness direction and accordingly can be applied to an article 4 without interposing a pressure-sensitive adhesive sheet or a layer of a pressure-sensitive adhesive material but the surface site of the other side in the thickness direction has nontackiness. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a sheet body that is mounted on an article that requires predetermined characteristics and exhibits the characteristics, a laminate using the sheet body, a product on which the sheet body is mounted, and a method for manufacturing the sheet body.

  There is a sheet body formed by mixing a filler for exhibiting a predetermined characteristic with a binder. This sheet body is configured by mixing soft magnetic powder as a filler in a synthetic resin material as a binder, for example, and is used as an absorption layer or suppression layer that absorbs or suppresses electromagnetic waves. Specific examples include a sheet-like composition called an electromagnetic interference suppressor having a noise suppressing effect, an electromagnetic wave absorbing performance, an electromagnetic wave shielding effect, or the like. This electromagnetic interference suppressor prevents electromagnetic waves radiated from an article from adversely affecting other articles, or incoming electromagnetic waves from adversely affecting an article, and prevents electromagnetic waves radiated from an article or electromagnetic waves arriving at an article. Used to be attached to an article to absorb or attenuate. Specific articles include electronic devices that are becoming thinner, higher performance, and higher functionality (for example, mobile phones, digital cameras, personal computers, projector devices, car navigation devices, ECU (Electronic Control Unit) circuit boards) Etc.) is used as a relatively simple electromagnetic interference suppression means. In many cases, the adhesive is attached to an article (electronic device, device, cable, etc.) with an adhesive sheet or an adhesive material layer interposed on the surface of one side in the thickness direction of the sheet body. For example, an electromagnetic interference suppressor is affixed to the back side of a liquid crystal panel of a mobile phone and used to reduce radiation noise generated by other devices or emitted from an antenna itself, or in an FPC (Flexible Printed Circuit) circuit. It is used for the purpose of sticking and reducing transmission noise. Further, in the electromagnetic induction type wireless communication of the RFID technology, there is a problem that communication cannot be performed when there is a communication obstructing member such as metal near the antenna coil. The real part μ ′ of the relative permeability is high, the imaginary part μ ″ is low, and the electric resistance value is high). In this case, not the noise reduction but rather the characteristic of collecting and passing the magnetic field is required. Yes.

  Electronic devices in which electromagnetic waves are a problem are being pursued to reduce the thickness and size of the devices themselves, leaving only the minimum necessary space for heat dissipation. It is required to fit in the gap and develop the necessary electromagnetic interference effect. The requirement becomes stricter every time the model is changed, and it is necessary to make it as thin as possible. However, one adhesive layer does not progress in thickness, and the adhesive layer that is thicker than the electromagnetic interference suppression body, which is the main body, has a narrow space. Some examples occupy a place inside. When the pressure-sensitive adhesive sheet or the pressure-sensitive adhesive layer is interposed as described above, an occupied area (space) for mounting the electromagnetic interference suppression body is increased by the thickness of the pressure-sensitive adhesive sheet and the pressure-sensitive adhesive layer. Patent Document 1 discloses an electromagnetic interference suppressor that reduces the occupied area. The electromagnetic interference suppressor is configured such that the absorption layer has adhesiveness and can be attached to an article using the adhesiveness.

JP 2003-142871 A

  The electromagnetic interference suppressor shown in Patent Document 1 is imparted with adhesiveness by forming a soft magnetic metal powder mixed in an adhesive material. This electromagnetic interference suppressor is considered to have adhesiveness on both sides. In such an absorbent layer, the surface portion on one side in the thickness direction may have adhesiveness for sticking to an article, but the surface portion on the other side in the thickness direction has adhesiveness. Before sticking to the device, if there is no separator on both sides, dust and other foreign objects will easily adhere, and even when storing in roll form, it will be necessary to consider the influence of adhesiveness on both sides, Handling will be inferior.

  An object of the present invention is to provide a sheet body that is easy to handle. Furthermore, in addition to handling, the object is to provide a sheet having high performance. In the present invention, only one surface has adhesiveness. As a result, the release paper (separator) only needs to be provided on one side, and foreign matter such as dust does not adhere to the sheet before being attached to the device, and handling is improved.

  In the present invention, a filler having a predetermined property is mixed with a binder to be formed into a sheet shape, the surface portion on one side in the thickness direction is sticky, and the surface portion on the other side in the thickness direction is non-sticky It is a sheet | seat body characterized by having.

In the present invention, the binder is made of a material having adhesiveness,
The surface portion on one side in the thickness direction is formed in a mirror shape, and the surface portion on the other side in the thickness direction is formed in a rough surface shape having irregularities.

  Further, the present invention is characterized in that the property of the binding material changes from tackiness to adhesiveness by satisfying a predetermined condition.

  Further, the present invention is characterized in that the binder is made of a material blended with a first material having adhesiveness around room temperature and a second material having a glass transition point and / or a softening point at 50 ° C. or higher. To do.

In the present invention, the filler is in the form of particles and is surface-treated with a treatment agent.
The solubility parameter of the treatment agent is characterized by being closer to the solubility parameter of the second material than the solubility parameter of the first material.

The present invention is also characterized by flame retardancy.
Moreover, this invention is a laminated body which laminated | stacked the other functional layer which has the characteristic different from the characteristic of a filler on the surface part of the thickness direction other side of said sheet | seat body.

  Moreover, this invention is a laminated body by which said several sheet body is adhere | attached and laminated | stacked using the adhesiveness of the surface part of the thickness direction one side.

  In the present invention, two sheet bodies adjacent to each other in the thickness direction are laminated in a state where a surface portion on one side in the thickness direction of one sheet body and a surface portion on the other side in the thickness direction of the other sheet body are opposed to each other. It is characterized by that.

  Further, the present invention is characterized in that two sheet bodies adjacent in the thickness direction are laminated in a state where the surface portions on one side in the thickness direction of each sheet body face each other.

  Moreover, this invention is a product with which said sheet | seat body is mounted | worn with articles | goods using the adhesiveness of the surface part of the thickness direction one side.

Further, the present invention is a coating step of applying a fluid material in which a filler having a predetermined property is mixed with a binder to a support having a surface portion formed into a mirror surface;
And a solidifying step of solidifying the material applied to the support.

  According to the present invention, the filler having a predetermined characteristic is a sheet body that is mixed with the binder and formed into a sheet shape, and this sheet body can exhibit the characteristics of the filler. Moreover, since this sheet | seat body has adhesiveness in the surface part of the thickness direction one side, it can be stuck on articles | goods, without interposing an adhesive sheet or an adhesive material layer. Therefore, this sheet body can reduce the occupation area for mounting this sheet body. Further, since the sheet body has non-adhesiveness on the surface portion on the other side in the thickness direction, foreign matters such as dust do not adhere to the surface portion on the other side in the thickness direction, and the characteristics of the sheet body due to the adhesion of the foreign materials No adverse effects. Therefore, the labor for preventing dust and the like from attaching is unnecessary, and handling is easy.

  In addition, this sheet body can be attached without using an adhesive sheet or an adhesive material layer, and there is no need for troubles to prevent dust and the like from being attached. Can do.

  According to the invention, the sheet body uses a bonding material made of an adhesive material, the surface portion on one side in the thickness direction is formed into a mirror surface, and the surface portion on the other side in the thickness direction has a rough surface. It is formed in a shape.

  The surface portion formed in a mirror-like shape has a lot of binders made of an adhesive material and is effectively present, and has a large area in contact with the article when being attached to the article. You can touch more. On the other hand, the surface portion formed into a rough surface having irregularities has a large amount of filler, and the area that comes into contact with the article is small when sticking to the article. Do not touch. Therefore, the surface portion formed in a mirror surface is adhered to the article, whereas the surface portion formed in a rough surface having irregularities is not adhered to the article.

  Further, according to the present invention, the properties of the binder change from adhesive to adhesive when satisfying a predetermined condition. For example, when a predetermined condition is satisfied in a state where the sheet body is adhered to the article, the property of the binder is changed and the binder is cured. When the binder is cured in a state where the sheet body is adhered to the article, the binder is cured by filling the unevenness in the article, so that the sheet body is adhered to the article. Before the properties of the binding material change, the sheet body is sticky and can be easily affixed to or peeled off from the article. After the property of the binder is changed, the binder is cured and the sheet body and the article are bonded to each other, so that the sheet body can be firmly attached to the article. The predetermined condition may be a change with time, or may cause a chemical reaction by applying photocuring, electron beam crosslinking, or the like to one side of the sheet. In addition, by causing a chemical reaction, it is possible to accelerate the shortening of the curing time by changing the properties.

  According to the invention, the binder is made of a material blended with a first material having adhesiveness around room temperature and a second material having a glass transition point and / or a softening point at 50 ° C. or higher.

  Since the first material is near the normal temperature and not in the glass state, the storage elastic modulus near the normal temperature is low. Since a material with a low storage elastic modulus tends to exhibit high tackiness, the first material exhibits high tackiness near room temperature.

  Since the second material is near the normal temperature and is in the glass state or below the softening point, the storage elastic modulus near the normal temperature is high. Since the material having a high storage elastic modulus exhibits high cohesiveness in the temperature range, the second material exhibits high cohesiveness near room temperature. When a paste in which a binder and filler are dissolved or dispersed in a solvent is applied to a support in the form of a sheet and then dried to form a sheet, a highly cohesive material causes the filler to almost settle and flow. In addition, the solvent can be volatilized while maintaining the filler dispersion state and orientation state in the sheet formed during processing. That is, even if the solvent is volatilized and the binder is reduced in volume, the filler hardly moves, so the surface portion on the support side is a mirror surface without irregularities, but the opposite surface portion without the support is Volume reduction cannot be controlled, resulting in a rough surface with irregularities.

  When the first material and the second material are blended without phase-separation rather than being completely miscible (making them like a microphase-separated structure), the blended material has two glass transition points. Both the tackiness of the first material and the cohesion of the second material. Furthermore, when blending so as to obtain a microphase separation structure, a material having a balance between adhesiveness and cohesiveness can be obtained by an easy operation.

  From the above, in the sheet body using the material in which the first material and the second material are blended as a binder, the surface portion on the support side is a mirror surface, and the surface portion on the side without the substrate is a rough surface. Therefore, the surface part on one side in the thickness direction has adhesiveness, and the surface part on the other side in the thickness direction becomes non-adhesive sheet body.

  According to the invention, the filler is in the form of particles and is surface-treated with the treatment agent, and the solubility parameter of the treatment agent is closer to the solubility parameter of the second material than the solubility parameter of the first material. The solubility parameter of the filler surface-treated with such a treatment agent is closer to the solubility parameter of the second material than the solubility parameter of the first material. It is easier to disperse in the second material than the material, and the filler is unevenly distributed in the second material. As the surface treatment, a treatment agent (coupling agent, resin, etc.) extracted according to the dissolution parameter is present between the filler and the binder by coating, adhesion, thermal spraying, dipping and kneading.

  Therefore, when the first material is unevenly distributed on one side in the thickness direction of the sheet body 1, the filler 2 is unevenly distributed on the second material unevenly distributed on the other side in the thickness direction. A sheet body 1 having adhesiveness and having no adhesiveness on the other side in the thickness direction is obtained.

  Moreover, according to this invention, the flame retardance is provided to the sheet | seat body. The standard for flame retardancy is to obtain an evaluation of UL94V0, and a suitable amount of flame retardant and flame retardant aid is blended. Thus, it can be suitably used for articles such as electronic devices. In imparting flame retardancy to the sheet body, for example, a flame retardant or a flame retardant aid is added.

  Moreover, according to this invention, it is a laminated body which laminated | stacked the other functional layer which has a characteristic different from the characteristic of a filler on the surface part of the thickness direction other side of said sheet | seat body. Such a laminate is a laminate having a plurality of characteristics because other functional layers having characteristics different from the characteristics of the filler are laminated. Specific examples of the functional layer include a magnetic metal, a metal foil, a resistance film, a protective layer, and a conductor element layer.

  Moreover, according to this invention, it is a laminated body by which said several sheet body is adhere | attached and laminated | stacked using the adhesiveness of the surface part of the thickness direction one side.

  In this laminate, since a plurality of sheet bodies are laminated, characteristics due to the filler, for example, an electromagnetic interference suppression effect is exhibited more than in the case of a single sheet body. Furthermore, since this laminated body is laminated by adhering the sheet bodies using the adhesiveness of the sheet bodies themselves, it is not necessary to interpose an adhesive sheet or an adhesive material layer. Accordingly, the adhesive sheet or the pressure-sensitive adhesive layer does not deteriorate the characteristics, and a thin laminate can be obtained as compared with the laminated body laminated with the pressure-sensitive adhesive sheet or the pressure-sensitive adhesive layer interposed.

  If a sheet body as thick as the laminated body is produced in order to further exhibit the characteristics due to the filler, voids are formed in the sheet body and the characteristics due to the filler cannot be sufficiently exhibited. On the other hand, since this laminated body is laminated by adhering using the adhesiveness of the sheet body by sandwiching a plurality of sheet bodies with a roll or the like, it is laminated without impairing the properties of the sheet body. The characteristics due to the filler can be sufficiently exhibited. Further, when the binding material included in the sheet body is made of a material in which the first material and the second material are blended, by heating the roller to a temperature at which the second material does not soften but the first material softens, Only the first material is softened, and the unevenness of the sheet body to be adhered is filled and laminated. Therefore, this laminated body adheres firmly to each other and is not easily peeled off, and can fully exhibit the characteristics of the filler.

  Further, according to the present invention, two sheet bodies adjacent in the thickness direction are laminated in a state where the surface portion on one side in the thickness direction of one sheet body and the surface portion on the other side in the thickness direction of the other sheet body are opposed to each other. Is done. By doing so, since the surface part of the thickness direction one side of a sheet | seat body is exposed by doing so, it can be stuck to articles | goods etc., without using an adhesive sheet or an adhesive material layer.

  Moreover, according to this invention, the two sheet bodies adjacent to the thickness direction are laminated | stacked in the state where the surface parts of the thickness direction one side of each sheet body oppose. By doing so, since the surface parts which have adhesiveness oppose, sheet | seat bodies become more difficult to peel. Since this laminated body exposes the surface portion on the other side in the thickness direction of the sheet body, it is preferably used when the laminated body does not need to have adhesiveness.

  Moreover, according to this invention, said sheet | seat body is a product mounted | worn with articles | goods using the adhesiveness of the surface part of the thickness direction one side, and the apparatus provided with the function which a sheet | seat body has was obtained. Since the sheet body is attached to the article using the adhesiveness, the product can exhibit the characteristics of the filler without damaging the product.

  Further, according to the present invention, a fluidizing material in which a filler having a predetermined property is mixed with a binder is applied to a support having a surface portion formed in a mirror surface, and applied to the support. And a solidifying step for solidifying the material. By doing so, it is possible to produce a sheet that has the characteristics of a filler, the surface portion on one side in the thickness direction has adhesiveness, and the surface portion on the other side in the thickness direction has non-adhesiveness.

  FIG. 1 is a cross-sectional view of a sheet body 1 according to the present invention. The sheet body 1 is a sheet body formed by mixing a filler 2 for exhibiting predetermined characteristics with a binder 3. The sheet body 1 is not particularly limited as long as the sheet body 1 is attached to the article 4 and exhibits the characteristics of the filler. Examples of the filler 2 include a sheet body in which an insulator powder, a magnetic powder, a metal powder, a colorant, a fragrance, and a deodorant are mixed.

  As an example of the sheet body 1 according to the present invention, a sheet body configured by mixing soft magnetic powder as the filler 2 in the synthetic resin material as the binder 3 can be cited. Specifically, the sheet body 1 is a sheet body that absorbs, suppresses, or reflects electromagnetic waves, and is used as a suppression layer that constitutes the electromagnetic interference suppression body 1. The sheet body and the electromagnetic interference suppressing body are substantially the same, and are denoted by the same reference numeral “1”.

  The electromagnetic interference suppressor 1 absorbs and suppresses electromagnetic waves by the following mechanism. The electromagnetic interference suppressor 1 is often used in the vicinity of an electromagnetic wave oscillation source inside an electronic device, and a near electromagnetic field is a target. In the near electromagnetic field, the magnetic field impedance is low, and in particular, the real part (μ ′) and imaginary part (μ ″) of the complex relative permeability of the sheet must be increased to suppress it. When providing shielding and electromagnetic wave absorption, inconsistency and consistency of impedance including real part (ε ') and imaginary part (ε ") of complex relative permittivity in addition to the above μ' and μ" Will be designed.

  As shown in FIG. 1, the electromagnetic interference suppressor 1 is attached to the article 4 in order to prevent incoming electromagnetic waves from adversely affecting the article 4 and to absorb, suppress or reflect electromagnetic waves arriving at the article 4. Used. In addition, the electromagnetic interference suppressor 1 absorbs, suppresses, or reflects the electromagnetic wave radiated from the article 4 to prevent the electromagnetic wave radiated from the article 4 from adversely affecting other articles. You may install and use.

  Since this sheet body 1 has adhesiveness on the surface portion on one side in the thickness direction, it can be adhered to the article 4 without interposing an adhesive sheet or an adhesive material layer. Therefore, the occupation area for mounting the electromagnetic interference suppressing body 1 is reduced. Further, since the surface portion on the other side in the thickness direction does not have adhesiveness, foreign matter such as dust does not adhere before and after the electromagnetic interference suppressing body 1 is attached, and electromagnetic interference is suppressed by the attachment of the foreign matter. There is no adverse effect on the effect.

  As described above, the sheet body 1 can be adhered without using an adhesive sheet or an adhesive material layer, and does not require time and effort for preventing dust and the like from being attached. Can be reduced.

  In actuality, the sheet body 1 has a mirror-like surface portion on the side in contact with the article 4 and a rough surface having an uneven surface on the opposite side to the article 4. In this way, the sheet body 1 has a mirror surface on one side in the thickness direction and a rough surface on the other side in the thickness direction, and optimizes the composition and blending ratio of the filler 2 and the binder 3 and the like. By this, the sheet | seat body which has adhesiveness in the surface part of the thickness direction one side, and does not have adhesiveness in the surface part of the thickness direction other side is obtained.

  As shown in FIG. 1, the surface portion on the side in contact with the article 4 has many and effective binders 3 made of an adhesive material. Moreover, since it is mirror surface shape, when sticking to the articles | goods 4, the area which contacts the articles | goods 4 is large, and many materials which have adhesiveness can contact the articles | goods 4. FIG. On the other hand, as shown in FIG. 1, the surface portion on the opposite side of the article 4 has a large amount of filler 2 and has a small area in contact with the article 4 when adhered to the article 4. The material which has the property does not contact so much. Therefore, the surface portion formed in a mirror surface is adhered to the article 4, whereas the surface portion formed in a rough surface having irregularities is not adhered to the article 4. The unevenness of the surface portion may be due to, for example, a decrease in the binding material 3 when the solvent is dried. However, in order to develop non-adhesiveness due to the unevenness, the profile, groove, In addition, it is possible to apply unevenness processing such as embossing.

  As the filler 2, powder having each function can be used. The function of the filler 2 determines the function of the sheet body 1. Functional fillers include magnetic powder, thermally conductive fillers, dielectric materials, carbons and hollow bodies. A known magnetic powder can be used for the use of the electromagnetic interference suppressor 1 and is not particularly limited, and may be a soft magnetic powder or a hard magnetic powder. Examples of the soft magnetic powder include magnetic stainless steel (Fe—Cr—Al—Si alloy), sendust (Fe—Si—Al alloy), permalloy (Fe—Ni alloy), silicon copper (Fe—Cu—Si alloy), Fe-Si alloys, Fe-Si-B (-Cu-Nb) alloys, Fe-Ni-Cr-Si alloys, Fe-Si-Cr alloys, Fe-Si-Al-Ni-Cr alloys, amorphous alloys , Ferrite, iron-based particles, and pure iron particles. Examples of the ferrite include soft ferrites such as Mn—Zn ferrite, Ni—Zn ferrite, Mn—Mg ferrite, Mn ferrite, Cu—Zn ferrite, and Cu—Mg—Zn ferrite. Examples of iron-based particles include iron oxide. Examples of pure iron particles include carbonyl iron powder. Examples of the hard magnetic powder include hard ferrite which is a permanent magnet material. As the magnetic powder, soft magnetic powder is preferable.

  The filler 2 is in the form of particles. Specifically, the particles may be spherical, lump, needle, scale, fiber, coil, or their approximate shape. When soft magnetic powder is used as the filler, there is no particular limitation on the shape of the soft magnetic powder, and spherical, flat and fibrous shapes can be used, and the flat soft magnetic powder has high magnetic permeability. A flat shape is preferred. Therefore, the filler 2 is more preferably a flat soft magnetic powder. The magnetic powder may be used alone, or a plurality of magnetic powders may be mixed and used.

  The average particle size of the filler 2 is preferably 1 μm to 300 μm, more preferably 5 μm to 200 μm, and even more preferably 5 μm to 100 μm. The aspect ratio of the filler 2 is preferably 2 or more and 500 or less, more preferably 5 or more and 100 or less, and still more preferably 10 or more and 100 or less. The average particle size is a value obtained by measuring with a particle size distribution measuring device (LA-300, manufactured by Horiba, Ltd.).

  As the binder 3, known elastomers and resins can be used, and are not particularly limited. The elastomer may be a thermoplastic elastomer or a thermosetting elastomer. For example, polyvinyl chloride such as chlorinated polyethylene, polystyrene, polyolefin, polyurethane, silicone, polyamide and the like. Examples include elastomers such as derivatives and derivatives thereof. The resin may be a thermoplastic resin or a thermosetting resin. For example, polyurethane resin, polyester resin, polyester urethane resin, polyvinyl acetal resin, polyethylene resin, polypropylene resin, AS (acrylonitrile-styrene copolymer) Polymer) resin, ABS (acrylonitrile-butadiene-styrene copolymer) resin, polystyrene resin, polyvinyl chloride resin, chlorinated polyethylene resin, polyvinylidene chloride resin, polyvinyl acetate resin, ethylene-vinyl acetate copolymer resin, silicone Resin, fluorine resin, acrylic resin, polyamide resin (nylon (R)), polycarbonate resin, polyethylene terephthalate resin, alkyd resin, unsaturated polyester resin, polysulfone resin, phenol resin, urea resin Epoxy resins, polyimide resins and polylactic acid resins and derivatives thereof. These elastomers and resins may be used singly, but a plurality of binders may be mixed and used, and the binder 3 is a copolymer composed of the above elastomer or resin. Also good. The binding material 3 is a material having adhesiveness, and may be a binding material that exhibits adhesiveness alone, or may be a binding material that exhibits adhesiveness by mixing a plurality of binding materials. Further, it may be a crosslinked type or a non-crosslinked type.

  In addition, the binder 3 is preferably a material in which a first material having adhesiveness near normal temperature and a second material having a glass transition point and / or a softening point at 50 ° C. or higher are blended.

  The reason for this configuration will be described below. The sheet body 1 is caused to exhibit adhesiveness or adhesiveness only on the surface portion on one side in the thickness direction of the sheet body 1 mainly due to the difference in surface state between both surfaces of the sheet body 1. However, when only the first material, which is an adhesive, is used as the binder 3, there is a problem that dispersion control and orientation control of the filler 2 are insufficient, and it is difficult to achieve high performance as an electromagnetic interference suppressor. Come on. As a problem for high performance, the first material itself has a low storage elastic modulus in the range from room temperature to high temperature, so that when it is used as the binder 3, the dispersion state of the highly rigid filler 2 must be sufficiently maintained. This is because the dispersion control and orientation control of the filler 2 in the sheet body 1 are insufficient as a result.

  One of the improvements in the performance of electromagnetic interference suppressors is to increase the real part (μ ′) and imaginary part (μ ″) of the complex relative permeability while ensuring the insulation of the sheet body 1. It is necessary to perform dispersion control and orientation control for dense orientation in a manner that does not contact the flat magnetic metal that is the filler 2. Such dispersion and orientation control include multilayer lamination coating, magnetic field orientation, and pressurization. This is achieved by using an effect such as pressing. However, when the first material is used as the bonding material 3, this control becomes very difficult.

  The reason for this is that although the dispersion and orientation of the filler 2 are controlled by the shearing force applied to the sheet body 1, the dispersion of the filler 2 is maintained when the storage elastic modulus (E ′) of the binder 3 itself is low. This is because the force is weak, difficult to control, and even if controlled, it returns due to relaxation.

  For this reason, it is necessary to change the viscoelastic properties of the binder 3 in order to improve performance. Basically, a material obtained by blending a first material having a low storage elastic modulus around room temperature and a second material having a high elastic modulus around room temperature is used as the binder 3. This is because the binding material 3 needs to satisfy both contradictory properties of a high storage elastic modulus and a low storage elastic modulus. Therefore, a configuration in which the first material and the second material as described above are blended is preferable.

  Since the first material is near the normal temperature and not in the glass state, the storage elastic modulus near the normal temperature is low. Since a material with a low storage elastic modulus tends to exhibit high tackiness, the first material exhibits high tackiness near room temperature. The first material is not particularly limited as long as it is a material that is not in a glass state near normal temperature, and known resins and elastomers can be used. Examples of the first material include an acrylic resin, a silicone resin, a material obtained by adding an adhesive resin to an acrylic resin, or an adhesive resin alone. The adhesive resin referred to here is generally called a tackifier, and includes a phenol resin, a ketone resin, a rosin resin, a rosin derivative, an alicyclic saturated carbon resin, and the like.

  Since the second material is near the normal temperature and is in the glass state or below the softening point, the storage elastic modulus near the normal temperature is high. Since the material having a high storage elastic modulus exhibits high cohesiveness in the temperature range, the second material exhibits high cohesiveness near room temperature. When a paste in which a binder 3 and a filler 2 are dissolved or dispersed in a solvent is applied to a support in the form of a sheet and then dried to form a sheet, the highly cohesive material is almost settled. Without flowing, the solvent can be volatilized while maintaining the dispersion state and orientation state of the filler 2 in the sheet 1 formed during processing. In other words, even if the solvent is volatilized and the volume of the binder 3 is reduced, the filler 2 hardly moves, so that the surface portion on the support side is a mirror surface with no unevenness, but the surface portion on the opposite side without the support body The volume reduction cannot be controlled, and the surface becomes uneven.

The value of the storage elastic modulus (E ′) will be specifically described below. The first material is a material that is also used as the bonding material 3 having adhesiveness at room temperature, but is a material having a storage rigidity (E ′) at room temperature of less than 10 ⁷ Pa (JIS K 7244-1). The second material has a glass transition point of room temperature or lower, and a glass transition point and a softening point satisfying [softening point−glass transition point ≧ 45 ° C.], or a material having a glass transition point, / Or a material whose softening point is not in the range of room temperature to room temperature + 30 ° C. and whose storage elastic modulus (E ′) at room temperature is twice or more that of the first material in the same temperature range, specifically, the second material A material which is an elastomer or a resin having a storage elastic modulus (E ′) at room temperature of 10 ⁷ Pa (JIS K 7244-1) or more can be used. The softening point can be measured according to JIS K 7206. If it has such a characteristic, well-known resin and elastomer can be used, and it does not restrict | limit in particular. Examples of the second material include urethane resin, ester resin, chlorinated polyethylene, epoxy resin, phenol resin, urethane elastomer, and polyvinyl acetal resin. In addition, room temperature and normal temperature are 0-35 degreeC.

The storage elastic modulus (E ′) of the second material is 10 ⁷ Pa or more at room temperature, but it is desirable to keep this value even at room temperature + 30 ° C. At this time, if it is 10 ⁷ Pa or more at room temperature, a glass transition point or a softening point may exist in this temperature range, and the storage elastic modulus (E ′) may be 10 ⁷ Pa or more. In addition, it is preferable that above-described room temperature and normal temperature are 0-35 degreeC. It can be said that it is more preferable that the storage elastic modulus (E ′) of 10 ⁷ Pa or more is maintained from room temperature to around 80 ° C. or more because the possibility of being affected by the actual use environment is reduced.

  When the first material and the second material are blended without phase-separation rather than being completely miscible (making them like a microphase-separated structure), the blended material has two glass transition points. Both the tackiness of the first material and the cohesion of the second material.

  Mixing so that the glass transition point does not become one, and maintaining the state requires a device that maintains a micro-mixed state in a combination that is not compatible, that is, a combination that does not mix between molecules. Become. As one means, it is possible to use a method of preparing a cast film in which a good solvent for both materials is dissolved and kneaded, and then the solvent is rapidly blown to solidify the dispersion state. In this case, when the molecular weight is higher than a certain level, the dispersion morphology can be fixed due to the entanglement effect between the molecules. Further, the first material and the second material may be blended in a form that forms an IPN (Interpenetrating Polymer Network). For example, by using a functional group having only one of the blended materials, for example, a cluster of metal salts is formed in the blend. It may be one in which the morphology is fixed in a microphase separation state in the form of formation.

The mixing ratio of the first material and the second material can be any ratio between 0.01 and 100 by weight ratio. This is because blending the second material with the first material increases the cohesive force of the first material, but at the same time the adhesive force moves in a direction that is impaired, so it is only necessary to be able to balance it. . This means that when the first material and the second material or higher materials are used in a blended manner as described above, whether it is a completely compatible system, a micro phase separation system or a macro phase separation system, After that, it is described that the sheet 1 can be used as a binding material 3 of the sheet 1 as long as the cohesive force and the adhesiveness are balanced. When blending as described above, at least the storage rigidity (E ′) at room temperature after blending needs to exceed 10 ⁷ Pa (JIS K 7244-1).

  When the first material and the second material are completely mixed (completely compatible), the mixture has a glass transition point at a temperature higher than the glass transition point of the first material and lower than the glass transition point of the second material. In many cases, the properties of the first material and the second material are not exhibited. Therefore, it is particularly preferable to blend so as to have a microphase separation structure, since it is possible to achieve a balance between cohesive force and adhesiveness by an easy operation rather than complete compatibility.

  From the above, when the binding material 3 is a material in which the first material and the second material are blended, the sheet body 1 has a mirror-like surface portion on the support side, and the surface opposite to the substrate. A part is formed in the rough surface shape which has an unevenness | corrugation. Therefore, the surface part of the thickness direction one side has adhesiveness, and the surface part of the thickness direction other side has non-adhesiveness.

  The glass transition point is a value obtained by measurement as follows. Using a differential scanning calorimeter (DSC) (manufactured by Max Science, 3100S), the sample was heated at a heating rate of 10 ° C. per minute according to Japanese Industrial Standard (JIS) K7121-1987, and the DSC curve was measured. Draw the endothermic peak corresponding to the glass transition of the obtained DSC curve at a point where the slope is maximum with respect to the straight line that extends the base line on the high temperature side to the low temperature side and the curve from the rising part of the peak to the vertex. The temperature at the intersection with the tangent line was determined as the glass transition point. In addition to this, it can be measured by obtaining the peak top temperature of tan δ (= E ″ / E ′) from the result of dynamic viscoelasticity measurement in accordance with JIS K 7244-1. It can be measured according to JIS K 7206.

  The binding material 3 is preferably a binding material whose properties change from tackiness to adhesiveness when a predetermined condition is satisfied. For example, the binding material 3 is preferably a binding material that changes its properties and cures when a predetermined condition is satisfied in a state where the sheet 1 is adhered to the article 4. When the binding material 3 is cured while the sheet body 1 is adhered to the article 4, the binding material 3 is cured by filling the unevenness in the article 4, so that the sheet body 1 is adhered to the article 4. Such a sheet body 1 requires the sheet body 1 because the sheet body 1 exhibits adhesiveness and can be easily attached to or peeled off from the article 4 before the properties of the binding material 3 change. It can be accurately applied to any location. After the property of the binding material 3 is changed, the binding material 3 is cured and the sheet body 1 and the article 4 are bonded, so that the sheet body 1 can be firmly attached to the article 4. The predetermined condition may be a change with time, or may cause a chemical reaction by applying photocuring, electron beam crosslinking, or the like to one side of the sheet. In addition, by causing a chemical reaction, it is possible to accelerate the shortening of the curing time by changing the properties. The time until curing (curing time) is preferably 4 hours or more and 1 week or less. If it is shorter than 4 hours, it will harden while the sheet 1 is attached to the article (while stirring and coating), and if it is longer than one week, it will be shipped before it is firmly attached. Will cause concerns such as peeling. For example, the thing which hardens | cures gradually after mounting | wearing is preferable.

  The filler 2 may be a surface-treated filler. As the surface treatment, a known treatment can be used, and examples thereof include a surface treatment using a treatment agent such as a coupling agent and a coating agent, a plating treatment and an oxidation treatment. As the surface treatment using the treatment agent, the treatment agent (coupling agent, resin, etc.) extracted according to the dissolution parameter is present between the filler 2 and the binder 3 by coating, adhesion, thermal spraying, immersion, kneading and the like. It depends.

  As the treating agent, a treating agent whose solubility parameter is close to the solubility parameter of the second material as compared with the solubility parameter of the first material is preferable. The solubility parameter represents a measure of compatibility, and materials having similar solubility parameters are likely to be mixed, and materials having different solubility parameters are not likely to be mixed. Examples of coupling agents include silane coupling agents, titanium coupling agents, nonionic coupling agents, aluminate coupling agents, and the like, and coupling agents containing long chain alkyl groups are also used. can do. As the coating agent, for example, a known resin is used, and a resin satisfying the above conditions is preferably used. The solubility parameter of the filler 2 surface-treated with such a treatment agent is closer to the solubility parameter of the second material than the solubility parameter of the first material, and the filler 2 surface-treated with the treatment agent is It is easier to disperse in the second material than in the first material, and the filler 2 is unevenly distributed in the second material. Therefore, when the first material is unevenly distributed on one side in the thickness direction of the sheet body 1, the filler 2 is unevenly distributed on the second material unevenly distributed on the other side in the thickness direction. A sheet body 1 having adhesiveness and having no adhesiveness on the other side in the thickness direction is obtained. The amount of the coupling agent used is preferably 0.01% or more and 5% by weight or less with respect to the filler 2. If it is less than 0.01%, the filler 2 cannot be sufficiently surface-treated, and the dissolution parameter can hardly be changed. When the amount is more than 5% by weight, the spacing between the fillers 2 is increased and the electromagnetic wave absorption performance is lowered. The amount of the coating agent used is preferably 0.01% or more and 10% by weight or less with respect to the filler 2. If it is less than 0.01%, the filler 2 cannot be sufficiently surface-treated, and the dissolution parameter can hardly be changed. When the amount is more than 10% by weight, the interval between the fillers 2 is increased and the electromagnetic wave absorption performance is lowered. The plating process and the oxidation process are performed for the purpose of imparting insulation to the filler 2. Furthermore, in the case of plating treatment, it is possible to impart magnetism or thermal conductivity.

  The blending ratio of the filler 2 and the binder 3 is preferably such that the filler 2 is 30% by volume or more and 80% by volume, and the binder 3 is 20% by volume or more and 70% by volume, more preferably. 2 is 40 volume% or more and 70 volume%, and the binder 3 is 30 volume% or more and 60 volume%. When the filler 2 is less than 30% by volume and the binder 3 is more than 70% by volume, the electromagnetic wave absorbing effect cannot be sufficiently exhibited. Further, if the filler 2 is more than 80% by volume and the binder is less than 20% by volume, the sheet body 1 becomes brittle, so that processing becomes difficult.

  The sheet body 1 preferably has flame retardancy. The standard for flame retardancy is to obtain an evaluation of UL94V0, and a suitable amount of flame retardant and flame retardant aid is blended. Thus, it can be suitably used for articles such as electronic devices. In imparting flame retardancy to the sheet body 1, for example, a flame retardant or a flame retardant aid is added to the sheet body 1. The flame retardant is not particularly limited, and phosphorus compounds, boron compounds, bromine-based flame retardants, zinc-based flame retardants, nitrogen-based flame retardants, hydroxide-based flame retardants, and the like can be used in appropriate amounts. Examples of the phosphorus compound include phosphate esters and titanium phosphate. Examples of the boron compound include zinc borate. Examples of brominated flame retardants include hexabromobenzene, decabromobenzyl phenyl ether, decabromobenzyl phenyl oxide, tetrabromobisphenol and ammonium bromide. Examples of the zinc-based flame retardant include zinc carbonate, zinc oxide, and zinc borate. Examples of nitrogen flame retardants include melamine compounds such as triazine compounds, hindered amine compounds, melamine cyanurate compounds, and melamine anidine compounds. Examples of the hydroxide flame retardant include magnesium hydroxide and aluminum hydroxide.

  The sheet body 1 may contain a dispersant. By adding a dispersing agent, the dispersibility of the filler 2 can be improved. As the dispersant, a known dispersant can be used, and examples thereof include a mixture of a higher fatty acid and a higher fatty acid salt. Examples of the higher fatty acid include stearic acid, lauric acid, maleic acid, and behenic acid. Examples of the higher fatty acid salts include aluminum salts, sodium salts, lithium salts, barium salts, calcium salts and magnesium salts, zinc salts and the like of the above higher fatty acids. The ratio of the higher fatty acid to the higher fatty acid salt (higher fatty acid / higher fatty acid salt) is preferably 10/90 to 90/10 in weight ratio.

  The thickness of the sheet body 1 is preferably 1 μm or more and 2 mm or less, and more preferably 10 μm or more and 500 μm or less. If the thickness is less than 1 μm, the electromagnetic wave absorbing effect of the sheet body 1 cannot be exhibited sufficiently. If it is thicker than 2 mm, the occupied area for mounting the sheet body 1 becomes large.

  The manufacturing method of the sheet body 1 includes a coating process in which a fluid material in which a filler 2 having predetermined characteristics is mixed with a binder 3 is applied to a support body having a mirror-like surface portion. A solidification step of solidifying the material applied to the body.

  The fluid material in which the filler 2 is mixed with the binder 3 is a paste-like mixture in which the filler 2, the binder 3 and the dispersant are dissolved or dispersed in a solvent using a dispersing device or a kneading device. (Magnetic paint).

  A known solvent can be used as the solvent, and is not particularly limited. Examples thereof include ketones, alcohols, esters, ethers, aromatic hydrocarbon compounds and halogenated hydrocarbon compounds. Examples of ketones include acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone, and cyclohexane. Examples of alcohols include methanol, ethanol, propanol, butanol, isopropyl alcohol and the like. Examples of the esters include methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl lactate, and ethyl glycol acetate. Examples of ethers include diethylene glycol dimethyl ether, 2-ethoxyethanol, tetrahydrofuran and dioxane. Examples of the aromatic hydrocarbon compound include benzene, toluene and xylene. Examples of the halogen-based hydrocarbon compound include methylene chloride, ethylene chloride, carbon tetrachloride, chloroform and chlorobenzene. A solvent may be used independently and may mix and use 2 or more types of solvents.

  The amount of the solvent used is preferably 400 parts by weight or more and 1500 parts by weight or less, and more preferably 400 parts by weight or more and 1200 parts by weight or less with respect to 100 parts by weight of the binder. If it is less than 400 parts by weight, the viscosity is high and difficult to process, and if it is more than 1500 parts by weight, the viscosity becomes too low and voids are formed inside the sheet body 1, which is not preferable.

  A known apparatus can be used as the dispersing apparatus or kneading apparatus, and is not particularly limited. Examples include kneaders, agitators, ball mills, sound mills, roll mills, extruders, ultrasonic dispersers and 2-axis planetary kneaders. When flat magnetic materials are used, flat magnetic materials are destroyed and distorted. An agitator, a ball mill, a roll mill, a homogenizer, an ultrasonic disperser, and a two-shaft planetary kneader that do not give the resistance are preferred.

  As the support, a known support can be used as long as it is in the form of a sheet and the surface portion is formed into a mirror surface, and is not particularly limited. Examples thereof include paper, paper laminated with a polymer resin such as polyolefin, polymer resin, cloth, nonwoven fabric, and metal. The polymer resin is preferable because it is thin and has high strength. For example, polyesters such as polyethylene terephthalate and polyethylene-2,6-naphthalate, polyolefins such as polyethylene and polypropylene, fluorine resins in which part or all of hydrogen of these polyolefins is substituted with fluorine, cellulose triacetate and cellulose diacetate, etc. Cellulose derivatives, vinyl resins such as polyvinyl chloride, vinylidene resins such as polyvinylidene chloride, polycarbonate resins, polyphenylene sulfide, polyamideimide, and polyimide. The surface treatment is preferably performed with a treatment agent closer to the solubility parameter of the first material than the solubility parameter of the second material. By doing so, the 1st material which has adhesiveness can be unevenly distributed to the support body side. Further, it is preferable that the support is subjected to a release treatment on the surface with a release agent such as a silicone resin. The support body which gave the peeling process can peel the sheet | seat body 1 easily. Moreover, it is preferable that the thickness of a support body is 3 micrometers or more and 1 mm or less. If the thickness is less than 3 μm, wrinkles are generated and the formed sheet body is damaged. If it is thicker than 1 mm, it is difficult to bend, so that the peeling operation for peeling the sheet body becomes difficult.

  As a coating method, a known coating method can be used and is not particularly limited. For example, air doctor coat, blade coat, wire bar coat, air knife coat, squeeze coat, impregnation coat, reverse roll coat, transfer roll coat, gravure coat, kiss coat, cast coat, extrusion coat, die coat, spin coat and comma coat Is mentioned.

  Moreover, you may make it apply | coat in the application | coating process, applying a magnetic field. For example, a permanent magnet is installed above or below the support and a magnetic field is applied in the vertical direction (thickness direction of the sheet 1). The sheet body 1 obtained by applying the magnetic field while applying a magnetic field can orient the flat soft magnetic body in the in-plane direction, and can fill the soft magnetic powder with higher density. The strength of the magnetic field (magnetic flux density) varies depending on the types of the binder 3 and the flat soft magnetic powder dissolved or dispersed in the solvent, but is generally preferably 0.01 Tesla or more and 1 Tesla or less. If it is smaller than 0.01 Tesla, it cannot be fully oriented, and if it is larger than 1 Tesla, the magnetic material as the filler 2 is magnetized and the magnetic materials are aggregated.

  The end material cut off to make the sheet 1 formed on the support into a predetermined shape can be collected, peeled off from the support, and reused. For example, by adding to the above magnetic paint, it can be easily dissolved or dispersed in the solvent in the paint and can be reused.

  Moreover, a crosslinking agent may be added to crosslink the binder 3 to improve the heat resistance of the sheet body 1. In this case, it becomes difficult to reuse.

  The sheet body 1 has characteristics different from those of the filler 2 by laminating another functional layer having characteristics different from the characteristics of the filler 2 on the non-adhesive surface portion on the other side in the thickness direction. Since the other functional layers having the above are laminated, a laminated body having a plurality of characteristics can be obtained. A known functional layer can be used as the functional layer, and is not particularly limited. Examples thereof include a magnetic metal, a metal foil, a resistance film, a protective layer, a conductor element (antenna) layer, an insulating layer, a magnetic shield layer, a reflective layer, a resistance layer, a reinforcing layer, a release layer, and a metal layer.

  By attaching the sheet body 1 to the article 4 using the adhesiveness of the surface portion on one side in the thickness direction, an apparatus having the function of the sheet body 1 is obtained. The device provided with the function of the sheet body 1 is a device that can prevent the electromagnetic wave radiated from the article 4 from adversely affecting other articles or the incoming electromagnetic wave from adversely affecting the article 4. is there. In addition, since the sheet body 1 is attached to the article 4 using adhesiveness, the article is not damaged.

  For example, it is used in home appliances such as television receivers, computers such as personal computers, portable terminal devices such as mobile phones, and electronic devices such as medical devices. The sheet body (electromagnetic interference suppressor) 1 according to the present invention is appropriately cut out and attached to an electronic device, so that electromagnetic waves radiated from the article have an adverse effect on other articles, or incoming electromagnetic waves have an adverse effect on the article. Can be prevented.

  In portable information terminals having an IC (Integrated Circuit) tag function called RFID (Radio Frequency Identification), in order to shield external electromagnetic waves, a metal casing or a casing subjected to a conductive treatment such as metal plating is used. When a transmission / reception antenna disposed in the housing is close to the housing, magnetic field lines generated around the antenna during transmission / reception are formed in parallel to the metal surface of the housing, and an eddy current is generated on the metal surface. Since the magnetic field generated from this eddy current is formed in a direction that cancels the electric field generated during transmission and reception, the magnetic field that can be used for communication is greatly attenuated, and the communication distance is significantly shortened. As a method for improving the wireless communication, there is a method of disposing an electromagnetic interference suppressing body between the antenna and the housing, and the sheet body (electromagnetic interference suppressing body) 1 according to the present invention can be used. In this case, the sheet body (electron interference body) 1 has a high electric resistance value at a communication frequency (for example, 13.56 MHz band), and further has a real part (μ ′) of complex relative permeability at the frequency as a magnetic characteristic. ) Is high and the imaginary part (μ ″) of the complex relative permeability at the same frequency is required to be low. This is because the eddy current is not generated in the sheet body 1 itself due to the high electric resistance value, and μ When 'is high, the magnetic field of this frequency can be easily taken into the sheet body 1, and when μ ″ is low, the magnetic field taken in can be passed without loss due to heat conversion or the like. In this application, in addition to the portable information terminal, the same effect can be obtained when the antenna coil of the tag inlet having a coil such as a non-contact IC card or a label tag or the antenna coil of a reader or reader / writer is compatible with metal. it can.

  In general, the electromagnetic interference suppressing body 1 is desired to be thin, but the thick electromagnetic interference suppressing body 1 is used in order to sufficiently exhibit the electromagnetic interference suppressing effect and extend the communication distance of the RFID. There are also uses. The thick electromagnetic interference suppression body 1 is a laminate in which a plurality of thin electromagnetic interference suppression bodies are stacked. By simply sandwiching a plurality of electromagnetic interference suppressing bodies 1 with a roll or the like, the electromagnetic interference suppressing bodies 1 do not adhere to each other, and a laminate cannot be formed. Therefore, a laminated body is formed by sandwiching a plurality of electromagnetic interference suppressing bodies 1 with a roller heated to a temperature at which the electromagnetic interference suppressing body 1 melts. However, if the temperature is set so as to melt the electromagnetic interference suppressor 1, the electromagnetic interference suppressor 1 may stick to the roll, and stable production cannot be performed. In some cases, self-heating may occur, and temperature adjustment becomes more difficult. Moreover, if the electromagnetic interference suppression body 1 is adhered to the roll and the sheet shape cannot be maintained, or the dispersion state and orientation state of the filler are changed, the electromagnetic interference suppression effect cannot be sufficiently exhibited.

  In addition, when the electromagnetic interference suppressing body 1 that is as thick as the above-described laminated body is manufactured at once instead of being laminated in order to extend the communication distance of the RFID, a gap is formed in the electromagnetic interference suppressing body 1 and the electromagnetic interference suppressing effect is produced. Cannot be fully utilized.

  The electromagnetic interference suppression body 1 is made to adhere to another electromagnetic interference suppression body 1 using the adhesiveness of the surface portion on one side in the thickness direction, thereby obtaining a laminate in which a plurality of electromagnetic interference suppression bodies 1 are stacked. . In this laminated body, since a plurality of electromagnetic interference suppressing bodies 1 are laminated, the electromagnetic interference suppressing effect is exhibited more than the case of a single electromagnetic interference suppressing body 1. Further, since the electromagnetic interference suppression bodies 1 are adhered to each other by using the adhesiveness of the electromagnetic interference suppression body 1 itself, the laminate does not need to interpose an adhesive sheet or an adhesive material layer. Accordingly, the effect of suppressing electromagnetic interference is not lowered by the pressure-sensitive adhesive sheet or pressure-sensitive adhesive layer, and a thin laminate can be obtained as compared with a laminated body laminated with the pressure-sensitive adhesive sheet or pressure-sensitive adhesive layer interposed.

  An example of a method for manufacturing the laminate 11 will be described. FIG. 2 is a schematic view showing a laminating apparatus 10 for laminating two electromagnetic interference suppressing bodies 1. The laminating apparatus 10 is provided with a pair of rollers 12, a pressure unit 13, a heating unit 14, and the like. The pressurizing unit 13 applies a spring force in a direction in which the pair of rollers 12 are brought close to each other.

  The laminating apparatus 10 conveys, for example, two electromagnetic interference suppressing bodies 1 held in a rolled state between the rollers 12 by the rollers 12. At that time, in the two electromagnetic interference suppression bodies 1, the surface portion 15 on one side in the thickness direction of one electromagnetic interference suppression body 1 and the surface portion 16 on the other side in the thickness direction of the other electromagnetic interference suppression body 1 face each other. So that it is conveyed. Then, the two electromagnetic interference suppressing bodies 1 conveyed between the rollers 12 are pressed by the pressing unit 13. By doing so, the two electromagnetic interference suppression bodies 1 are integrated using the adhesiveness of the electromagnetic interference suppression body 1 itself, and the laminated body 11 is obtained.

  At that time, the heating means 14 heats at least one of the rollers 12. The roller 12 may be heated by the heating means 14 to soften the electromagnetic interference suppressing body 1. For example, when the binding material 3 included in the electromagnetic interference suppressing body 1 is made of a material in which the first material and the second material are blended, the second material is not softened by the heating means 14 but the first material is not softened. By heating to a temperature that softens, only the first material is softened, and the unevenness of the electromagnetic interference suppressing body 1 to be adhered is filled and laminated. Therefore, the laminated body 11 obtained in this way can adhere | attach the electromagnetic interference suppression bodies 1 firmly, is hard to peel, and can fully exhibit an electromagnetic interference suppression effect.

  The laminated body 11 includes two electromagnetic interference suppressing bodies 1 adjacent to each other in the thickness direction. The electromagnetic interference suppressing body 1 includes a surface portion 15 on one side in the thickness direction and the other electromagnetic interference suppressing body 1 in the thickness direction. The side surface portion 16 is laminated so as to face each other. Accordingly, since the surface portion 18 on one side in the thickness direction of the electromagnetic interference suppressing body 1 is exposed, this laminate can be attached to an article or the like without using an adhesive sheet or an adhesive material layer.

  The laminated body 11 is a laminated body in which two electromagnetic interference suppressing bodies 1 are laminated, but is not limited to two, and may be a laminated body in which three or more are laminated.

  The laminated body 11 includes two electromagnetic interference suppression bodies 1, one surface portion 15 in the thickness direction of one electromagnetic interference suppression body 1 and the other surface portion 16 in the thickness direction of the other electromagnetic interference suppression body 1. However, they may be laminated in a state where the surface portions on one side in the thickness direction of each sheet body are opposed to each other. By doing so, since the surface parts which have adhesiveness oppose, electromagnetic interference suppression bodies 1 become more difficult to peel. This laminated body is preferably used when the surface of the electromagnetic interference suppression body 1 on the other side in the thickness direction is exposed and the laminated body 11 does not need to have adhesiveness.

  Moreover, although this embodiment demonstrated the sheet | seat body (electromagnetic interference suppression body) 1 which has an electromagnetic interference suppression effect, this invention mixes the filler 2 which has a predetermined characteristic with the binder 3, and is sheet-like. What is necessary is just the sheet | seat body 1 formed in this.

  As other examples, if the properties of the filler 2 are to be obtained by the sheet body 1, all of them are targeted. Specifically, sensor sheets (pressure-sensitive conductive sheets, sheets that detect changes in dielectric constant and / or magnetic permeability due to contact and approach), heat dissipation sheets (thermal conductive sheets), resonance suppression sheets, and the like are applied products. It is possible.

  EXAMPLES Hereinafter, although an Example and a comparative example are given and this invention is demonstrated in detail, this invention is not limited to a following example.

The materials used in the following examples and comparative examples are as follows.
Binders ・ Polyurethane resin (second material): NIPPOLAN manufactured by Nippon Polyurethane Industry Co., Ltd. ・ Acrylic resin (first material): Vinesol manufactured by Yushi Co., Ltd.

Filler-Flat soft magnetic powder (flat Fe-Ni-Cr-Si powder): JEM powder manufactured by Mitsubishi Materials Corporation

Dispersant ・ Stearic acid: Stearic acid manufactured by NOF Corporation ・ Barium stearate: NS-B manufactured by Lead City Chemical Industry Co., Ltd.

The polyurethane-based resin has a glass transition point of −55 ° C. and a softening point of 100 ° C., and has a storage elastic modulus (E ′) at room temperature of 10 ⁷ Pa or more. The acrylic resin has a glass transition point of around 10 ° C. and a storage elastic modulus (E ′) at room temperature of 10 ⁵ to 10 ⁶ Pa. The solvent used for preparing the paint is a mixed solvent mainly composed of toluene, and its azeotropic point is about 80 to 100 ° C.

[Examples 1 and 2 and Comparative Example 1]
(Preparation of electromagnetic interference suppressor)
A solvent was added to the composition (blending amount) shown in Table 1 to prepare a magnetic coating material, which was coated and dried on PET (polyethylene terephthalate, release support) by a doctor blade method to form a sheet. Next, an electromagnetic interference suppressing body (sheet body) having a thickness of 100 μm was obtained by peeling off from the peeling support. For the obtained electromagnetic interference suppressor, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Example 3]
(Surface treatment of flat soft magnetic powder (resin coating))
First, the surface treatment of flat Fe-Ni-Cr-Si powder (flat soft magnetic powder) was performed with an epoxy-based thermosetting resin manufactured by Reginas Chemical Co., Ltd. The resin coating amount is 4% by weight with respect to the content of the flat soft magnetic powder (that is, flat soft magnetic powder: resin = 100: 4 by weight ratio). Further, as a post-treatment, a heat treatment was performed at 150 ° C. for 30 minutes to thermally cure the coated resin.

The resin used for the surface treatment was as follows, and the main agent and the curing agent were mixed at a ratio of 10: 1, and the surface of the flat Fe—Ni—Cr—Si powder was resin-coated using this.
Main agent: A-7516 (Reginas Kasei Co., Ltd.)
Curing agent: H-7610 (manufactured by Reginas Kasei Co., Ltd.)

(Preparation of electromagnetic interference suppressor)
As flat soft magnetic powder, instead of using flat Fe-Ni-Cr-Si powder, the above surface-treated (resin coated) flat Fe-Ni-Cr-Si powder (treated flat magnetic powder) was used. Example 1 is the same as Example 1 except that the composition (mixing amount) of Example 3 shown in FIG. For the obtained electromagnetic interference suppressor, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Example 4]
(Production of laminate)
According to the method for manufacturing the above laminate, two electromagnetic interference suppressors (Example 2) are converted into a surface portion on one side (smooth surface side) in the thickness direction of one electromagnetic interference suppressor and the other electromagnetic interference suppressor. Is laminated in a state where the surface portion on the other side in the thickness direction (uneven surface side) faces each other. By doing so, a laminate having a thickness of 200 μm was obtained. With respect to the obtained laminate, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Example 5]
(Production of laminate)
Example 4 is the same as Example 4 except that three electromagnetic interference suppressors (Example 2) are stacked. By doing so, a laminated body having a thickness of 300 μm was obtained. With respect to the obtained laminate, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Comparative Example 2]
(Production of laminate)
By laminating two electromagnetic interference suppressing bodies (Comparative Example 1) with a double-sided tape having a thickness of 100 μm interposed therebetween, a laminated body having a thickness of 300 μm was obtained. With respect to the obtained laminate, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Comparative Example 3]
(Preparation of electromagnetic interference suppressor)
Example 1 is the same as Example 1 except that the thickness is 200 μm. With respect to the obtained laminate, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Comparative Example 4]
(Preparation of electromagnetic interference suppressor)
Example 1 is the same as Example 1 except that the thickness is 300 μm. With respect to the obtained laminate, the actual specific gravity / theoretical specific gravity was determined and shown in Table 1.

[Example 6]
(Production of laminate)
Two electromagnetic interference suppression bodies (Example 2) are stacked in a state where the surface portions on one side (smooth surface side) in the thickness direction of each electromagnetic interference suppression body are opposed to each other by the method for manufacturing the above laminate. . The obtained specific gravity / theoretical specific gravity was determined and shown in Table 2.

  In Tables 1 and 2, the amount of each component is shown in parts by weight. Here, as shown in Table 1, when the flat soft magnetic powder is 26% by volume, the binder is 72% by volume, and the remainder is other components such as a dispersant. That is, the sum of the flat soft magnetic powder and the binder does not become 100% by volume. Moreover, the room temperature at the time of the said measurement was 25 degreeC.

  About Examples 1-6 and Comparative Examples 1-4, the transmission loss measurement, the adhesive force measurement, and the surface roughness measurement were performed as follows. The results are shown in Tables 1 and 2. Moreover, about Example 2, SEM (scanning electron microscope) observation was performed.

(Transmission loss measurement)
A microstrip line with an impedance Z = 50Ω was used for measurement of transmission loss at 1 GHz and 2 GHz. The microstrip line is a method for measuring transmission loss of nearby noise that is widely used due to its structure suitable for mounting surface-mounted components and ease of production. FIG. 3 is a schematic diagram showing the shape of the microstrip line used for measuring the transmission loss. In this configuration, a linear conductor path 22 is provided on the surface of the insulator substrate 21, and the electromagnetic interference suppressing body 1 is placed on the conductor path 22. Both ends of the conductor path 22 are connected to a network analyzer (not shown). Then, with respect to the incident wave indicated by the arrow A, the reflection amount (dB) (indicated by the arrow S11) and the transmission amount (dB) (indicated by the arrow S21) from the placement site of the electromagnetic interference suppressing body 1 are measured The difference was defined as the loss amount, and the transmission loss (absorption amount) was determined from the following formula (1).
Transmission loss (absorption amount) = 1− | S11 | ² − | S21 | ² (1)

  The transmission loss of the microstrip line increases as the thickness of the electromagnetic interference suppressor 1 increases. In general, an electromagnetic interference suppressor 1 having a small thickness and high transmission loss is desired.

(Adhesive strength measurement)
The adhesive strength test was measured by the 180 degree peeling adhesive strength test method defined in JIS Z0237. In addition, this adhesive force shows that an adhesive force is so high that a number is large.

(Surface roughness measurement)
For the surface roughness, the degree of roughness of the sheet surface was measured using SURFTEST SJ-201 manufactured by Mitutoyo Corporation. Measurement values and measurement methods are based on JIS B0601. The average roughness (Ra) is a numerical value obtained by summing the absolute values of deviations from the average line of the measured values of roughness to the measurement curve and averaging them. The maximum height (Ry) indicates the sum of the height from the average line of roughness measurement values to the highest peak and the depth to the deepest valley bottom. The surface roughness can be evaluated by the average roughness and the maximum height.

(SEM observation)
The surface state of both surfaces of the sheet, in particular, the dispersed state of the soft magnetic metal powder near the surface was evaluated by SEM observation. When observing the surface state, the conductive film (carbon vapor deposition, etc.) was not processed, but the morphology of the electron beam penetrated further from near the sheet surface and permeated through the resin skin layer near the sheet was observed. did it. 4 is an SEM photograph of the surface portion (surface portion showing adhesiveness) on one side in the thickness direction of the electromagnetic interference suppressor that is Example 2, and FIG. 5 is the thickness of the electromagnetic interference suppressor that is Example 2. It is a SEM photograph of the surface part (surface part which shows non-adhesiveness) of a direction other side. The magnetic metal in the SEM photograph has an average particle size of about 40 μm and an aspect ratio of 20 to 45.

  As is apparent from Table 1, when the first material (adhesive, adhesive resin, acrylic resin) is included as the binding material 3 (Examples 1 to 3), the adhesive force is expressed (has adhesiveness). On the other hand, if the first material is not included as the binding material 3 (Comparative Example 1), it does not depend on the unevenness of the sheet surface and does not express any adhesive force (has non-adhesiveness).

  And even if it contains the 1st material as binder 3 (examples 1-3), adhesive strength is changed by changing the degree of surface roughness (average roughness Ra and maximum height Ry) of both sides of sheet object 1. It can be seen that a size difference can be given to. That is, the surface portion on one side in the thickness direction where the degree of surface roughness is small develops adhesive strength, whereas the surface portion on the other side in the thickness direction where the degree of surface roughness is large does not develop adhesive strength.

  Furthermore, when the first material and the second material (a material having a high softening point and a high storage elastic modulus (E ′) at room temperature) are blended into the binder 3 (Examples 2 and 3), It was found that the effect of suppressing electron interference can be increased while maintaining the adhesiveness of the surface portion (one side) on the side. Although the performance improvement due to the effect of the binder 3 is essentially dependent on the amount of magnetic metal, the effect of suppressing electronic interference depends on the amount of magnetic metal in Example 2 compared to Example 1, High performance is achieved as a sheet, and a remarkable effect can be obtained. By blending the second material, the cohesive force of the binder 3 is increased, the residual air of the sheet is also reduced, and the actual specific gravity of the sheet 1 approaches the theoretical specific gravity. Along with this, the value of transmission loss is improved. In other words, high performance can be achieved by increasing the specific gravity.

  Further, as can be seen from FIGS. 4 and 5, from the SEM photograph, the soft magnetic metal powder is oriented and dispersed on the adhesive surface (the surface portion on one side in the thickness direction of the present invention). appear. It can be said that the orientation state is more uniform than the surface having a large degree of unevenness (the surface portion on the other side in the thickness direction of the present invention). This is because the adhesive surface never functions only as an adhesive layer, but has a soft magnetic metal powder in it and is in an oriented dispersed state, so that the adhesive layer and the soft magnetic layer function simultaneously. It is to support that. Further, the disorder of the orientation of the magnetic metal seen in FIG. 5 is caused by the uneven state of the surface, which contributes to non-adhesiveness. As a result of the improved cohesiveness of the binder 3, the entire sheet (sheet body 1) is in a state where control of orientation and dispersion and single-sided adhesiveness are balanced despite high filling of the filler 2. It can be said.

  The laminates (Examples 4 to 6) in which the electromagnetic interference suppressors (Example 2) including the binder 3 in which the first material and the second material are blended are 200 μm and 300 μm in thickness, respectively. It was found to be thicker than the electromagnetic interference suppressing body (Example 2) and to have a large electromagnetic interference suppressing effect. Furthermore, the laminated body (Examples 4 and 5) laminated in a state where the surface portion on the smooth surface side and the surface portion on the uneven surface side face each other, either one of the surface portions is an adhesive surface, and expresses adhesive force. Therefore, it can be attached to articles without using double-sided tape, and is easy to handle.

  Comparative Example 2 in which an electromagnetic interference suppressor (Comparative Example 1) that does not include the first material as the binder 3 is laminated using a double-sided tape has the same thickness and the same electromagnetic interference suppression effect as Example 5. Demonstrate, but does not develop any adhesive strength on either side. Therefore, when affixing to an article, an adhesive sheet such as a double-sided tape or an adhesive material layer must be used, which is difficult to handle and becomes thicker than Example 5.

  Rather than laminating the electromagnetic interference suppressor (Comparative Example 1), Comparative Example 3 having a thickness of 200 μm by one coating increases the residual air (void) in the electromagnetic interference suppressor, and the actual specific gravity is Keep away from theoretical specific gravity. Along with this, the value of transmission loss was deteriorated and the electromagnetic interference suppression effect was not improved despite the increase in thickness. Further, when the thickness was set to 300 μm by one coating (Comparative Example 4), the electromagnetic interference suppression effect was not improved despite the increase in thickness as in Comparative Example 3. Therefore, even if a thick electromagnetic interference suppression body is produced by one coating, the electromagnetic interference suppression effect cannot be improved, and the electromagnetic interference suppression body with little residual air (void) is laminated to It was found that the interference suppression effect can be improved. Even when a thick electromagnetic interference suppressor is produced by a single coating, if the first material is included as the binder 3, an electromagnetic interference suppressor that is easy to handle because the adhesiveness is expressed on one side in the thickness direction. Is obtained.

  As mentioned above, the laminated body (Examples 4-6) which laminated | stacked the electromagnetic interference suppression body (Example 2) containing the binder 3 with which the 1st material and the 2nd material were blended improves an electromagnetic interference suppression effect. Can be made. Furthermore, the laminate (Examples 4 and 5) laminated in a state where the surface portion on the smooth surface side and the surface portion on the uneven surface side face each other can exhibit adhesiveness on the surface portion on one side, and is easy to handle. . Since the laminated body (Example 6) laminated in a state where the surface parts on the smooth surface side face each other, the surface parts having adhesiveness face each other, so that the sheet bodies are more difficult to peel off. Since this laminated body exposes the surface portion on the other side in the thickness direction of the sheet body, it is preferably used when the laminated body does not need to have adhesiveness. For example, a laminate that is wrapped with a PET film or the like for protection of an electromagnetic interference suppressor, or a laminate that is coated with a resin in a set with an RFID tag may be used.

In addition, the RFID communication distance was measured.
The communication distance between the tag 61 and the reader 62 was measured using a FeliCa reader / writer evaluation kit (13.56 MHz) manufactured by Sony Corporation. As the tag 61, Sony RC-S860 was used, and as the reading device 62, Sony RC-S440C was used.

  FIG. 6 is a schematic diagram showing a method for measuring a communication distance using an RFID system FeliCa reader / writer evaluation kit. As shown in FIG. 6, the measurement method is such that a laminate (Example 6) 11 is arranged on a tag 61 via a base 63, and further a metal plate 64 (iron foil, aluminum foil) is arranged. In the state, the communication distance L between the tag 61 and the reading device 62 was measured. The base material 63 used here is a dielectric material and does not have magnetic properties. For example, it is a substitute for an adhesive or a pressure-sensitive adhesive. In this evaluation, a PET film is laminated to have a thickness of 190 μm.

  The communication distance was about 10 cm in a free space without a metal plate, but the communication distance was 0 cm when the metal plate was installed close to the IC tag.

  When the laminated body (Example 6) 11 was used between the metal plate 64 and the antenna coil of the tag 61, the communication distance was 5.5 cm. Therefore, the communication distance improvement effect was recognized by using this invention.

  The material constants of the sheet body 1 of Example 6 for electromagnetic waves having a frequency of 1 MHz to 1 GHz (the real part μ ′ of the complex relative permeability, the imaginary part μ ″ of the complex relative permeability, the real part ε ′ of the complex relative permittivity, and The imaginary part ε ″) of the complex dielectric constant was measured by a coaxial tube method after ring processing (φ7 × φ3) of the material. The equipment used is a material analyzer (E4991A, manufactured by Agilent) for frequencies of 1 MHz to 1 GHz. The material constants were 13.56 MHz band μ ′ = 32.0, μ ″ = 2.0, ε ′ = 225.6, ε ″ = 29.2. As a result, even with the laminated sheets, high electrical resistance was observed from the low of high μ ′, low μ ″ and ε ″, and these characteristics supported the communication improvement effect of the tag 61 corresponding to metal.

It is sectional drawing of the sheet | seat body 1 which is this invention. It is the schematic which shows the lamination | stacking apparatus 10 which laminates | stacks the electromagnetic interference suppression body 1 of 2 sheets. It is the schematic which shows the shape of the microstrip line used for the measurement of transmission loss. It is a SEM photograph of the surface part (surface part which shows adhesiveness) of the thickness direction one side of the electromagnetic interference suppression body which is Example 2. FIG. It is a SEM photograph of the surface part (surface part which shows non-adhesiveness) of the thickness direction other side of the electromagnetic interference suppression body which is Example 2. FIG. It is the schematic which shows the measuring method of the communication distance by RFID system FeliCa reader / writer evaluation kit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Sheet body 2 Filler 3 Binding material 4 Article 10 Laminating apparatus 11 Laminated body 12 Roll 13 Pressurizing means 14 Heating means 21 Insulator substrate 22 Conductor path 61 Tag 62 Reading device 63 Base material 64 Metal plate

Claims (12)

  A filler having a predetermined property is mixed with a binder to be formed into a sheet shape, the surface portion on one side in the thickness direction has adhesiveness, and the surface portion on the other side in the thickness direction has non-adhesiveness. Characteristic sheet body. The binding material is made of an adhesive material,
2. The sheet body according to claim 1, wherein a surface portion on one side in the thickness direction is formed in a mirror shape, and a surface portion on the other side in the thickness direction is formed in a rough surface shape having irregularities.   The sheet according to claim 2, wherein the binding material changes its property from tackiness to adhesiveness by satisfying a predetermined condition.   The binding material is made of a material obtained by blending a first material having adhesiveness near normal temperature and a second material having a glass transition point and / or a softening point at 50 ° C or higher. The sheet body according to any one of 3. The filler is particulate and is surface treated with a treatment agent,
The sheet body according to claim 4, wherein the solubility parameter of the treatment agent is closer to the solubility parameter of the second material than the solubility parameter of the first material.   It has a flame retardance, The sheet | seat body as described in any one of Claims 1-5 characterized by the above-mentioned.   The laminated body which laminated | stacked the other functional layer which has the characteristic different from the characteristic of a filler on the surface part of the thickness direction other side of the sheet | seat body as described in any one of Claims 1-6.   A plurality of sheet bodies according to any one of claims 1 to 6, wherein the plurality of sheet bodies are adhered and laminated using the adhesiveness of the surface portion on one side in the thickness direction.   Two sheet bodies adjacent to each other in the thickness direction are laminated in a state where a surface portion on one side in the thickness direction of one sheet body and a surface portion on the other side in the thickness direction of the other sheet body are opposed to each other. The laminate according to claim 8.   The laminate according to claim 8, wherein two sheet bodies adjacent in the thickness direction are laminated in a state in which the surface portions on one side in the thickness direction of each sheet body are opposed to each other.   The product with which the sheet | seat body as described in any one of Claims 1-6 is mounted | worn with articles | goods using the adhesiveness of the surface part of the thickness direction one side. An application step of applying a fluid material in which a filler having a predetermined property is mixed with a binder to a support body having a mirror-like surface portion;
And a solidifying step of solidifying the material applied to the support.