KR20110056504A - Magnetic sheet composition, magnetic sheet, and method for producing magnetic sheet - Google Patents

Abstract

(식 중, m은 2 및 3 중 어느 하나이며, m과 n의 합은 4이다. Ar은 치환되어도 좋은 아릴기이며, R은 수소 원자 및 메틸기 중 어느 하나이다. n이 복수인 경우, R은 동일하여도 상이하여도 좋다).The present invention is capable of reducing unnecessary electromagnetic waves emitted from electronic devices and suppressing electronic disturbances generated in electronic devices. The magnetic sheet is low-temperature-curable, generates no odor, and does not generate corrosion. It is an object to provide a composition, a magnetic sheet and a method for producing a magnetic sheet.
The magnetic sheet composition of the present invention contains an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component. :

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different).

Description

Magnetic sheet composition, magnetic sheet and manufacturing method of the magnetic sheet {MAGNETIC SHEET COMPOSITION, MAGNETIC SHEET, AND METHOD FOR PRODUCING MAGNETIC SHEET}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic sheet composition, a magnetic sheet, and a method for producing a magnetic sheet as a material of a magnetic sheet capable of reducing unnecessary electromagnetic waves emitted from an electronic device and suppressing electromagnetic interference generated in the electronic device.

Examples of applications in which the magnetic sheets are used include noise suppression applications and RFID applications. As the noise suppression application, in accordance with the rapid progress of miniaturization and high frequency of electronic equipment represented by personal computers and mobile phones, the noise interference caused by electromagnetic waves from outside and the noise generated inside the electronic equipment In order to suppress interference, various noise countermeasures have been taken, and for example, providing a magnetic sheet (noise suppression sheet) in the vicinity of a noise source or a receiver.

The magnetic sheet includes a PET (magnetic sheet composition) containing PET (magnetic component), an epoxy resin, an acrylic resin, and a volatile solvent such as Fe-Si-Al, such as PET or peeled off PET. It apply | coated to the surface of an insulating support body (base material), hardened | cured by hot press, and shape | molded in the sheet form, The said magnetic component has a function as what is called a noise suppressor which suppresses noise. As for the noise suppression effect of the said magnetic sheet, it is preferable that mu "which is an imaginary part of permeability is large.

On the other hand, wireless communication using the coil antenna by the electromagnetic induction system is widespread as RFID use recently, as represented by the portable information terminal which has an IC tag function called RFID (Radio Frequency Identification). For example, as the portable information terminal, due to its miniaturization, various conductors (metals) such as metal cases and metal parts are arranged in the vicinity of the antenna element for transmitting and receiving. In this case, due to the presence of the metal near the antenna element, it is difficult to transmit and receive radio frequencies by greatly reducing the magnetic field available for communication, reducing the RFID communication distance in the electromagnetic induction method, or shifting the resonant frequency. There may be a case. Therefore, in order to suppress such electromagnetic interference, the magnetic sheet is arrange | positioned between the said antenna element and the said conductor. As a function of RFID, it is preferable that μ 'which is the real part of the magnetic permeability is larger, and that μ' which is the imaginary part is smaller.

Generally, the hardening agent (crosslinking agent) which hardens a thermosetting organic resin is added to the magnetic sheet composition as a material of the said magnetic sheet. As described above, the magnetic sheet is cured by containing a curing agent in the magnetic sheet composition. However, in the case where the polymer material in the magnetic sheet is easily absorbed, the thickness of the magnetic sheet changes with environmental changes in temperature and humidity. There is a problem. Here, in order to fully advance hardening of a magnetic sheet, when hardening temperature is made high and hardening time is long, since cooling time becomes long, the problem of waste of water and inferior productivity arises. In order to cope with this problem, when the curing temperature is increased and the curing time is shortened, there is a problem in terms of heat resistance of the insulating support.

As a conventional curing agent, a sulfonium-based cationic curing agent is often used, but since this sulfonium-based cation curing agent contains toxic antimony, there is a problem that it adversely affects the environment. Moreover, since this antimony sulfonium-type cation hardening | curing agent has Sb-F bond whose counter anion has weak binding force, F- ¹ ion is easy to be advantageous. Therefore, when a magnetic sheet containing an antimony-type cationic curing agent is used around the wiring, there is a problem that advantageous F- ¹ ions react with water to produce hydrofluoric acid, and wiring corrosion is frequent. In addition, after the curing reaction, an unpleasant odor remained in the magnetic sheet, and heat treatment was required to remove this unpleasant odor.

Moreover, since the magnetic sheet using the imidazole series hardening | curing agent has high hardening temperature, there exists a problem that press time is long, productivity is inferior, and there existed a problem that corrosion was easy to generate | occur | produce.

Further, for example, Patent Document 1 discloses an electromagnetic wave absorbing sheet having a concentration distribution in which a magnetic filler changes in the thickness direction from the surface of the magnetic binder containing a photocurable cation curing agent. Hardening of this electromagnetic wave absorption sheet is performed using a drum type apparatus.

In view of the above circumstances, a cation curing system using aluminum chelate as described below has been studied.

A complex (following formula (2)) is formed by coordinating the isolated electron band of oxygen of silanol in the co-coordinate of aluminum chelate (following formula (1)) which is Lewis acid. Subsequently, the composite (following formula (2)) and the epoxide as the monomer interact with each other to form a cationic polymerization active species (following formula (3)), and the cationic polymerization active species (following formula (3)) and the epoxide. By the cationic polymerization reaction proceeding between, polyethylene oxide (epoxy resin) (following formula (4)) can be obtained.

However, the reaction rate of the cationic polymerization reaction is very fast, and when aluminum chelate (Equation (1)) is used for, for example, a one-component adhesive or a film, the curing reaction proceeds even at room temperature, thereby reducing the required film life. It could not be obtained (it has hardened when the film was used), and the potential of aluminum chelate (formula (1) above) was required. Patent Literature 2 discloses encapsulating aluminum chelate and using it as a latent curing agent for the necessity of such latenting. Although encapsulation of this aluminum chelate was able to complete the potential of the curing agent and impart the stabilization and solvent resistance of the film life to the curing agent, there was a problem that the reactivity was lowered and the curing failure occurred.

[Patent Documents]

Patent Document 1: Japanese Patent Application Laid-Open No. 2007-95829

Patent Document 2: Japanese Patent Laid-Open No. 2006-70051

This invention solves the said problem in the past, and makes it a subject to achieve the following objectives. That is, the present invention is capable of reducing unnecessary electromagnetic waves emitted from electronic devices and suppressing electronic disturbances generated in electronic devices, being low-temperature-curable, not causing odors, and not causing corrosion. An object of the present invention is to provide a magnetic sheet composition, a magnetic sheet, and a method for producing the magnetic sheet as a material of the magnetic sheet.

MEANS TO SOLVE THE PROBLEM This inventor acquired the following knowledge as a result of earnestly examining in view of the said subject. That is, using a magnetic sheet composition containing an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component, The present invention has been completed by discovering that the magnetic sheet which is curable, does not generate odor, and does not generate corrosion.

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different).

This invention is based on the said knowledge of this inventor, The means for solving the said subjects are as follows. In other words,

It is a magnetic sheet composition characterized by containing an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component.

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different).

<2> Ar is a magnetic sheet composition as described in said <1> which is a phenyl group.

The <3> silanol compound or the alkoxysilane compound is a magnetic sheet composition as described in said <1> or <2> which is either any of triphenyl silanol, diphenylsilane diol, and diphenyl dimethoxysilane.

<4> The above-mentioned <1> to <3, wherein the aluminum chelate latent curing agent is an aluminum latent curing agent obtained by interfacially polymerizing a polyfunctional isocyanate compound and maintaining an aluminum chelating agent in a porous resin obtained by radical polymerization of divinylbenzene. It is a magnetic sheet composition in any one of>.

The magnetic component is 500 parts by mass to 1,250 parts by mass with respect to 106.1 parts by mass of the total amount of the <5> epoxy resin and the acrylic resin, and the total amount of the aluminum chelate latent curing agent and the silanol compound or the alkoxysilane compound is 2 parts by mass to 15 It is a magnetic sheet composition in any one of said <1>-<4> which is a mass part.

The magnetic sheet composition in any one of said <1> to <5> whose total amount of a <6> aluminum chelate latent hardening | curing agent, a silanol compound, or an alkoxysilane compound is 6.9 mass part-15 mass parts.

The mass ratio (aluminum chelate latent curing agent / silanol compound or alkoxysilane compound) of the <7> aluminum chelate latent curing agent and the silanol compound or the alkoxysilane compound is any one of the above <1> to <6>. Magnetic sheet composition described.

<8> It is a magnetic sheet which has a magnetic layer containing the magnetic sheet composition in any one of said <1>-<7>.

<9> A magnetic layer forming step of molding the magnetic sheet composition according to any one of <1> to <7> to form a magnetic layer, and at least one surface in the thickness direction of the magnetic layer, an uneven forming layer and a transfer material. After laminating and arrange | positioning in this order from the said magnetic layer side, the shape transfer which transfers the surface shape of the said transfer material to the surface of the said uneven | corrugated formation layer and the said magnetic layer, and simultaneously joins the said uneven | corrugated formation layer and the said magnetic layer is carried out. It is a manufacturing method of the magnetic sheet characterized by including the process.

ADVANTAGE OF THE INVENTION According to this invention, each said problem in the prior art can be solved, the reduction of the unnecessary electromagnetic wave emitted from an electronic device, and the suppression of the electromagnetic interference which generate | occur | produces in an electronic device are possible, it is low-temperature hardening, and it produces a bad smell It is possible to provide a magnetic sheet composition, a magnetic sheet, and a method for producing a magnetic sheet as a material of a magnetic sheet that is free from work and does not cause corrosion.

BRIEF DESCRIPTION OF THE DRAWINGS It is process drawing which shows an example of the manufacturing method of the magnetic sheet of this invention.

(Magnetic sheet composition)

The magnetic sheet composition of the present invention comprises at least an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component, Furthermore, it contains other components suitably selected as needed.

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different).

-Aluminum chelate latent curing agent-

As said aluminum chelate latent hardener, the thing which made the aluminum chelate hardener latent by various well-known methods, for example, a microencapsulation method, is mentioned. Especially, it is preferable to hold the aluminum chelating agent in the porous resin obtained by interfacial polymerization of the polyfunctional isocyanate compound. More specifically, not the microcapsule of the simple structure which coat | covered the core of the aluminum chelating-type hardening | curing agent with the shell of porous resin, but the thing of the structure in which the aluminum chelating agent was hold | maintained in the many fine pores which exist in a porous resin matrix. . Hereinafter, this aluminum chelate latent hardener is demonstrated.

Since the said aluminum chelate latent hardener is manufactured using an interfacial polymerization method, the shape is spherical, It is preferable that the particle diameter is 0.5 micrometer-100 micrometers from a point of sclerosis | hardenability and dispersibility, and also the hole of The size is preferably 5 nm to 150 nm in terms of curability and latentity.

In addition, since the latent degree of crosslinking degree of the porous resin used is too small, the said aluminum chelate latent hardening | curing agent tends to fall the thermal responsiveness, and when too large, the crosslinking degree is adjusted according to a use purpose. It is preferable to use the porous resin thus prepared. Here, the crosslinking degree of a porous resin can be measured by a micro compression test.

It is preferable that the said aluminum chelate latent hardener does not contain the organic solvent used at the time of the interfacial superposition | polymerization substantially, specifically, 1 ppm or less from the point of hardening stability.

In addition, since content of the porous resin and aluminum chelating agent in the said aluminum chelate latent hardening | curing agent is too low in aluminum chelating agent content, thermal responsiveness will fall and when too much, latent potential will fall, 100 mass of porous resins It is preferable that it is 10 mass parts-200 mass parts, and, as for content of the aluminum chelating agent with respect to parts, it is more preferable that they are 10 mass parts-150 mass parts.

In the said aluminum chelate latent hardening | curing agent, the complex compound which three (beta) -ketoenolate anion shown to following formula (5) arrange | positioned to aluminum is mentioned as an aluminum chelating agent.

Here, R ¹ , R ² and R ³ are each independently an alkyl group or an alkoxyl group. A methyl group, an ethyl group, etc. are mentioned as an alkyl group. As an alkoxyl group, a methoxy group, an ethoxy group, an oleyloxy group, etc. are mentioned.

Specific examples of the aluminum chelating agent represented by the formula (5) include aluminum tris (acetylacetonate), aluminum tris (ethylacetoacetate), aluminum monoacetylacetonate bis (ethylacetoacetate), and aluminum monoacetylacetonate bisole One acetoacetate, ethyl acetoacetate aluminum diisopropylate, alkyl acetoacetate aluminum diisopropylate, and the like.

There is no restriction | limiting in particular as said polyfunctional isocyanate compound, Although it can select suitably according to the objective, The compound which has two or more isocyanate groups in 1 molecule is preferable, and the compound which has three isocyanate groups is more preferable. As such a trifunctional isocyanate compound, the TMP adduct of Formula (6) which made 3 mol of diisocyanate compounds react with 1 mol of trimethylol propanes, the isocyanurate body of Formula (7) which self-condensed 3 mol of diisocyanate compounds, The biuret body of Formula (8) etc. which the 1 mole of diisocyanate which remain | survived in the diisocyanate urea obtained from 2 mol in 3 mol of diisocyanate compounds are mentioned.

In said (6)-(8), substituent R is the part except the isocyanate group of a diisocyanate compound. Specific examples of such diisocyanate compounds include toluene 2,4-diisocyanate, toluene 2,6-diisocyanate, m-xylylene diisocyanate, hexamethylene diisocyanate, hexahydro-m-xylylene diisocyanate and isophorone diisocyanate. And methylene diphenyl-4,4'-diisocyanate.

In the porous resin obtained by interfacial polymerization of such a polyfunctional isocyanate compound, a part of the isocyanate group undergoes hydrolysis and becomes an amino group between interfacial polymerizations, and the amino group and the isocyanate group react to form and polymerize urea bonds. Urea. The aluminum chelating latent curing agent comprising such a porous resin and the aluminum chelating agent held in the hole, when heated for curing, is not known for reasons, but the retained aluminum chelating agent coexists with the latent curing agent. It becomes possible to contact with the silanol compound, the alkoxysilane compound, and thermosetting resin represented by (A), and can advance hardening reaction.

When interfacially polymerizing the polyfunctional isocyanate compound, a radically polymerizable monomer such as divinylbenzene and a radical polymerization initiator may coexist and copolymerize, thereby improving the mechanical properties of the microcapsule wall. Thereby, the thermal response speed at the time of epoxy resin hardening can be increased.

In addition, although the aluminum chelating agent is considered to exist on the surface thereof due to the structure of the aluminum chelating latent curing agent, it is inactivated by water present in the system during interfacial polymerization, and the aluminum chelating agent is retained inside the porous resin only. It is thought that this activity was maintained and the resulting curing agent was able to obtain the potential.

The aluminum chelate latent curing agent dissolves an aluminum chelating agent and a polyfunctional isocyanate compound in a volatile organic solvent, and injects the obtained solution into an aqueous phase containing a dispersing agent and subjects it to interfacial polymerization by heating and stirring. Can be prepared accordingly.

In this production method, first, an aluminum chelating agent and a polyfunctional isocyanate compound are dissolved in a volatile organic solvent to prepare a solution that becomes an oil phase in interfacial polymerization. Here, the reason for using a volatile organic solvent is as follows. In other words, when a high boiling point bath having a boiling point of more than 300 ° C., such as that used in a conventional interfacial polymerization method, is used, since the organic solvent does not volatilize between interfacial polymerizations, the contact probability of isocyanate-water does not increase. This is because the degree of progress of interfacial polymerization of is insufficient. Therefore, even if it is interfacially polymerized, it is difficult to obtain a polymer having a good shape retention, and even if it is obtained, a high boiling point solvent is blown into the polymer, and when it is blended with the magnetic sheet composition, the high boiling point solvent is a cured product of the magnetic sheet composition. This is because it adversely affects the physical properties. For this reason, in this manufacturing method, a volatile thing is used as an organic solvent used when preparing an oil phase.

As such a volatile organic solvent, it is a good solvent (an each solubility of 0.1 g / ml (organic solvent) or more) of an aluminum chelating agent and a polyfunctional isocyanate compound, and does not dissolve substantially in water (solubility of water is 0.5 g / ml (organic solvent) or less) and the boiling point under atmospheric pressure are preferably 100 ° C or less. Specific examples of such volatile organic solvents include alcohols, acetate esters, ketones, and the like. Especially, ethyl acetate is preferable at the point of high polarity, a low boiling point, and poor water solubility.

If the amount of the volatile organic solvent is too small relative to 100 parts by mass of the total amount of the aluminum chelating agent and the polyfunctional isocyanate compound, the potential decreases, and if the amount is too large, the thermal responsiveness is 100 parts by mass to 500 parts by mass. desirable.

In addition, although the viscosity of the solution which becomes an oil phase can be reduced by using the usage-amount of a volatile organic solvent relatively large within the usage-amount of a volatile organic solvent, since the stirring efficiency improves when lowering a viscosity, the oil phase in a reaction system It becomes possible to refine | miniaturize an enemy more finely, and to make it uniform, and it becomes possible to make particle size distribution monodisperse, controlling the resultant latent hardener particle diameter to the magnitude | size of about a submicron-several microns. It is preferable to set the viscosity of the solution used as an oil phase to 1 mPa * s-25 mPa * s.

When PVA is used to emulsify and disperse the polyfunctional isocyanate compound, since the hydroxyl group of the PVA and the polyfunctional isocyanate compound react, the by-product adheres to the periphery of the latent curing agent particles as a foreign substance, or the particle shape itself. Or mold. In order to prevent this phenomenon, what promotes the reactivity of a polyfunctional isocyanate compound and water, or suppresses the reactivity of a polyfunctional isocyanate compound and PVA is mentioned.

In order to promote the reactivity of the polyfunctional isocyanate compound and water, the blending amount of the aluminum chelating agent is preferably 1/2 or less, more preferably 1/3 or less by weight of the polyfunctional isocyanate compound. This increases the probability that the polyfunctional isocyanate compound is in contact with water, and the polyfunctional isocyanate compound is easily reacted with water before the PVA contacts the oily surface.

Moreover, in order to suppress the reactivity of a polyfunctional isocyanate compound and PVA, the compounding quantity of the aluminum chelating agent in an oil phase is mentioned. Specifically, the blending amount of the aluminum chelating agent is preferably equal to or more than the weight of the polyfunctional isocyanate compound, more preferably 1.0 to 2.0 times. As a result, the isocyanate concentration at the oily surface is lowered. Moreover, since the reaction (interface polymerization) rate with the amine formed by hydrolysis is larger than a hydroxyl group, a polyfunctional isocyanate compound can reduce the reaction probability of a polyfunctional isocyanate compound and PVA.

When dissolving the aluminum chelating agent and the polyfunctional isocyanate compound in the volatile organic solvent, the mixture may be mixed at room temperature under atmospheric pressure, but may be heated as necessary.

Next, in this manufacturing method, the oil phase solution which the aluminum chelating agent and the polyfunctional isocyanate compound melt | dissolved in the volatile organic solvent is thrown into the water phase containing a dispersing agent, and it carries out an interfacial polymerization by heating and stirring. Here, as a dispersing agent, what is used in normal interfacial polymerization methods, such as polyvinyl alcohol, carboxymethylcellulose, gelatin, can be used. The amount of dispersant used is usually 0.1% by mass to 10.0% by mass of the aqueous phase.

Since the compounding quantity with respect to the aqueous phase of an oil phase solution is polydispersed when there are too few oily solutions, and when it is too large, aggregation will arise by refinement | miniaturization, It is preferable that they are 5 mass parts-50 mass parts with respect to 100 mass parts of water phases.

The emulsification conditions in interfacial polymerization are preferably stirring conditions (stirrer homogenizer; stirring speed of 8,000 rpm or more) such that the size of the oil phase is preferably 0.5 µm to 100 µm, and is usually 30 ° C under atmospheric pressure. -80 degreeC, the stirring time 2 hours-12 hours, and the conditions to heat-stirr are mentioned.

After the completion of the interfacial polymerization, the polymer fine particles are separated by filtration and naturally dried to obtain an aluminum chelate latent curing agent which can be used in the present invention. Here, the hardening characteristic of an aluminum chelate latent hardener can be controlled by changing the kind and usage-amount of a polyfunctional isocyanate compound, the kind and usage-amount of an aluminum chelating agent, and interfacial polymerization conditions. For example, when the polymerization temperature is lowered, the curing temperature can be lowered. On the contrary, when the polymerization temperature is higher, the curing temperature can be increased.

If the content of the aluminum chelate latent curing agent in the magnetic sheet composition of the present invention is too small, the content of the aluminum chelate latent curing agent is not sufficiently cured. If the content of the aluminum chelate latent curing agent is too high, the resin properties (for example, flexibility) of the cured product of the composition are lowered. It is preferable that it is 1 mass part-70 mass parts with respect to 100 mass parts of magnetic sheet compositions, and, as for content of a latent hardening | curing agent, it is more preferable that it is 1 mass part-50 mass parts.

In addition, the aluminum chelate latent curing agent may maintain the aluminum chelating agent in the porous resin obtained by the interfacial polymerization of the polyfunctional isocyanate compound or the porous resin obtained by the surface polymerization of the polyfunctional isocyanate compound and radical polymerization of the divinylbenzene. In the case of an aluminum chelate latent curing agent formed, for the purpose of improving low temperature fast curing properties, a silanol compound or an alkoxysilane compound represented by formula (A) described later may be impregnated. As an impregnation method, an aluminum chelate latent curing agent containing an aluminum chelate curing agent held in such a porous resin is dispersed in an organic solvent (for example, ethanol) and silanol represented by formula (A) in the dispersion. A compound or an alkoxysilane compound (e.g., triphenylsilanol) and, if necessary, an aluminum chelate-based curing agent (e.g., an isopropanol solution of monoacetylacetonate bis (ethylacetoacetate)) is added thereto at a temperature of room temperature to about 50 deg. The method of continuing stirring for several hours-overnight is mentioned.

-Silanol compounds or alkoxysilane compounds-

The said silanol compound or the alkoxysilane compound has the chemical structure of the following formula (A) unlike the conventional silane coupling agent which has a trialkoxy group.

In formula, R is either a hydrogen atom and a methyl group (when n is two or more, R may be same or different), m is 2 or 3, and the sum of m and n is four. Therefore, the silanol compound or alkoxysilane compound represented by Formula (A) becomes a compound which has one or two OR (hydroxy group or a methoxy group). "Ar" is an aryl group which may be substituted, but examples of the aryl group include a phenyl group, naphthyl group, anthracenyl group, azulenyl group, fluorenyl group, thienyl group, furyl group, pyrrolyl group, imidazolyl group, pyridyl group and the like. Can be mentioned. Especially, a phenyl group is preferable from a viewpoint of availability and acquisition cost. Although m pieces of Ar may be all the same or different, it is preferable that they are the same from the point of availability.

These aryl groups can have 1-3 substituents, For example, Halogen, such as chloro and bromo; Trifluoromethyl; Nitro; Sulfo; Alkoxycarbonyl such as carboxyl, methoxycarbonyl and ethoxycarbonyl; Electron withdrawing groups such as formyl, alkyl such as methyl, ethyl, and propyl; Alkoxy such as methoxy and ethoxy; Hydroxy; Amino; Monoalkylamino such as monomethylamino; Electron donating groups, such as dialkylamino, such as dimethylamino, etc. are mentioned. Moreover, since the acidity of the hydroxyl group of silanol can be raised by using an electron withdrawing group as a substituent, on the contrary, since acidity can be decreased by using an electron donating group, control of hardening activity becomes possible. Here, although m substituents may differ for every m Ar, it is preferable that m substituents are the same from the point of availability. In addition, only some Ar may have a substituent and other Ar may not have a substituent.

Also in the silanol compound or alkoxysilane compound represented by Formula (A), a triphenyl silanol, a diphenyl silanol, and a diphenyl dimethoxy silane is preferable, and triphenyl silanol is more preferable.

In the magnetic sheet composition of the present invention, when the content ratio of the silanol compound or the alkoxysilane compound to the total of the silanol compound or the alkoxysilane compound and the epoxy resin is too small, curing becomes insufficient, and when too large, the resin characteristics ( Since flexibility falls), 5 mass%-30 mass% are preferable, and 5 mass%-20 mass% are more preferable.

Moreover, it is preferable that the total amount of an aluminum chelate latent hardening | curing agent, a silanol compound, or an alkoxysilane compound is 2 mass parts-15 mass parts with respect to 106.1 mass parts of total amounts of an epoxy resin and an acrylic resin, and is 6.9 mass parts-15 mass parts. It is more preferable.

Moreover, it is preferable that the mass ratio (aluminum chelate latent hardener / silanol compound or an alkoxysilane compound) of an aluminum chelate latent hardener and a silanol compound or an alkoxysilane compound is 1.0 or less.

-Epoxy resin-

The said epoxy resin is used as a film-forming component. The epoxy resin may be either liquid or solid, and an epoxy equivalent is usually about 100 to 4,000, preferably having two or more epoxy groups in the molecule. Examples thereof include glycidyl ether type epoxy resins, alicyclic epoxy resins, bisphenol A type epoxy resins, phenol novolak type epoxy resins, cresol novolak type epoxy resins, and ester type epoxy resins. Especially, bisphenol-A epoxy resin can be used preferably from the point of resin characteristic. These epoxy resins also include monomers and oligomers.

Acrylic resin

It is preferable that the said acrylic resin has an epoxy group. In this case, reliability improves because the said epoxy group and the said aluminum chelate latent hardener react. Moreover, it is preferable that the said acrylic resin has a hydroxyl group further. By having the said hydroxyl group, adhesiveness can be improved.

As a weight average molecular weight of the said acrylic resin, 10,000-850,000 are preferable at the point which is excellent in applicability | paintability.

When the said weight average molecular weight is less than 10,000, the viscosity of the said magnetic sheet composition may become small, and it may become difficult to apply a large magnetic component, and when it exceeds 850,000, the viscosity of the said magnetic sheet composition may become large and apply | coat it. It may be difficult.

Moreover, as glass transition temperature of the said acrylic resin, -5 degreeC-+15 degreeC are preferable at the point of reliability.

When the said glass transition temperature is less than -5 degreeC, reliability in a high temperature or high temperature, high humidity environment may worsen, and when it exceeds +15 degreeC, there exists a tendency for the said magnetic sheet to become hard.

In addition to the epoxy resin and the acrylic resin, the magnetic sheet composition of the present invention may use an oxetane compound together in order to sharpen the exothermic peak. Examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3-ethyl-3-oxetanyl) methoxy] methyl} benzene, and 4,4'-bis [( 3-ethyl-3-oxetanyl) methoxymethyl] biphenyl, 1,4-benzenedicarboxylic acid bis [(3-ethyl-3-oxetanyl)] methyl ester, 3-ethyl-3- ( Phenoxymethyl) oxetane, 3-ethyl-3- (2-ethylhexyloxymethyl) oxetane, di [1-ethyl (3-oxetanyl)] methyl ether, 3-ethyl-3-{[3 -(Triethoxysilyl) propoxy] methyl} oxetane, oxetanylsilsesquioxane, phenol novolac oxetane and the like are preferable. When using an oxetane compound, 10 mass parts-100 mass parts are preferable with respect to 100 mass parts of epoxy resins, and 20 mass parts-70 mass parts are more preferable.

-Magnetic ingredient-

There is no restriction | limiting in particular as said magnetic component, According to the objective, it can select suitably, As a shape, a flat shape, a block shape, a fibrous form, spherical shape, an irregular shape, etc. are mentioned, for example. Among these, a flat shape is preferable at the point which the said magnetic component can be easily orientated to a predetermined direction, and high permeability can be aimed at.

As said magnetic component, a soft magnetic metal, ferrite, pure iron particle, etc. are mentioned, for example.

Examples of the soft magnetic metal include magnetic stainless steel (Fe-Cr-Al-Si alloy), sendust (Fe-Si-Al alloy), permalloy (Fe-Ni alloy), and silicon copper (Fe-Cu-Si alloy). , Fe-Si alloy, Fe-Si-B (-Cu-Nb) alloy, Fe-Ni-Cr-Si alloy, Fe-Si-Cr alloy, Fe-Si-Al-Ni-Cr alloy, etc. are mentioned. .

As said ferrite, soft ferrite, such as Mn-Zn ferrite, Ni-Zn ferrite, Mn-Mg ferrite, Mn ferrite, Cu-Zn ferrite, Cu-Mg-Zn ferrite, hard ferrite etc. which are permanent magnet materials, etc. are mentioned, for example. have.

The said magnetic component may be used individually by 1 type, and may use 2 or more types together.

There is no restriction | limiting in particular as content of the said magnetic component, Although it can select suitably according to the objective, It is preferable that the said magnetic component is 500 mass parts-1,250 mass parts with respect to 106.1 mass part of total amounts of the said epoxy resin and acrylic resin. . Moreover, it is preferable that the magnetic component contained in a magnetic sheet is 60 wt%-95 wt%.

When content of the said magnetic component is less than 500 mass parts with respect to 106.1 mass part of total amounts of the said epoxy resin and acrylic resin, the outstanding magnetic property may not be acquired, and the total amount of the said epoxy resin and acrylic resin may be 106.1 mass parts On the other hand, when it exceeds 1,250 parts by mass, it is difficult to connect and fix the magnetic component with the epoxy resin and the acrylic resin, and in a high temperature and high humidity environment, the thickness change of the magnetic sheet becomes large or weak, and the cross section of the magnetic sheet In addition, the magnetic component may also fall from the surface (powdering may occur).

-Other Ingredients-

As said other components, there is no restriction | limiting in particular, unless the effect of this invention is impaired, According to the objective, it can select suitably according to the objective, and aims at the improvement (adjustment of viscosity) of the coating property of the said magnetic sheet composition. In this case, a solvent may be added, and examples of the solvent include ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; Alcohols such as methanol, ethanol, propanol, butanol and isopropyl alcohol; Esters such as methyl acetate, ethyl acetate, propyl acetate, butyl acetate, ethyl lactate, ethyl glycol acetate; Ethers such as diethylene glycol dimethyl ether, 2-ethoxyethanol, tetrahydrofuran and dioxane; Aromatic hydrocarbon compounds such as benzene, toluene and xylene; And halogenated hydrocarbon compounds such as methylene chloride, ethylene chloride, carbon tetrachloride, chloroform and chlorobenzene. These may be used individually by 1 type and may use 2 or more types together. In addition, you may add various additives, such as a dispersing agent, a stabilizer, a lubricating agent, a silane coupling agent, a titanate coupling agent, a filler, such as a silica and a mica, a plasticizer, an antioxidant, a pigment, an antistatic agent, a flame retardant, as needed. .

-Flame Retardant-

By adding the flame retardant, the flame retardancy of the magnetic sheet can be improved.

As said flame retardant, the melamine cyanurate containing carboxylic acid amide is mentioned, for example.

As a conventional flame retardant, halogen-based compounds are mainly used, but when burned, there is a problem that harmful substances are generated and the load on the environment is large. Moreover, as a halogen-free flame retardant, the melamine cyanurate which is not surface-treated for example is known, but since the said melamine cyanurate has bad affinity with a resin component and it is hard to disperse | distribute in a resin component, In order to obtain a hard magnetic sheet, there is a problem that the mechanical strength of the magnetic sheet immediately after molding (pressing) is reduced (softened). In addition, since the mechanical strength is greatly reduced, it is difficult to increase the amount of the melamine cyanurate added, and sufficient flame retardancy cannot be obtained. Moreover, what is called "powder blowing" which a magnetic component falls out from the surface of a magnetic sheet tends to generate | occur | produce.

Here, the said melamine cyanurate is a melamine isocyanurate acid adduct, and melamine and isocyanurate are formed as an oligomer adduct by repeating addition reaction, as shown by following Reaction Formula.

Since the said melamine cyanurate has rigidity by a melamine frame | skeleton, and hydroxyl group (OH) arises by the said addition reaction, it is thought to express flame retardance by having polarity by the said hydroxyl group. However, the hydroxyl group often forms hydrogen bonds between molecules, and it is estimated that the hydrogen bond by the hydroxyl group causes the aggregation of isocyanurate. Therefore, by blocking this hydrogen bond, ie, using the melamine cyanurate in which some hydroxyl groups were protected, aggregation is suppressed and it is thought that the dispersibility in a resin component improves.

Therefore, as the flame retardant, melamine cyanurate containing carboxylic acid amide (melamine cyanurate surface-treated with fatty acid) was used, compared with melamine cyanurate (unsurface-treated). High flame retardancy is expressed, and powder blowing from the magnetic sheet surface is less likely to occur, and furthermore, in the case of using, for example, acrylic rubber as the resin component, it promotes curing of the resin component at the time of press, and the thickness under high temperature and high humidity environment. It was found that a magnetic sheet having good surface smoothness with a suppressed change can be obtained.

--- Melamine cyanurate containing carboxylic acid amide ---

The presence of the said carboxylic acid amide in the melamine cyanurate containing the said carboxylic acid amide can be confirmed, for example using pyrolysis gas chromatography (Py-GC-MS).

There is no restriction | limiting in particular as number average particle diameter of the melamine cyanurate containing the said carboxylic acid amide, Although it can select suitably according to the objective, 1 micrometer or less is preferable.

When the said number average particle diameter exceeds 1 micrometer, the said magnetic component may be densely orientated, the magnetic property of a magnetic sheet may be reduced, and the thickness change in a high temperature or high temperature, high humidity environment may become large.

The said number average particle diameter can be measured from the particle size distribution measured using the laser diffraction, for example.

The melamine cyanurate containing the said carboxylic acid amide may be a commercial item, and may be produced suitably.

As said commercial item, MC-5F (made by Sakai Chemical Co., Ltd.) etc. is mentioned, for example.

There is no restriction | limiting in particular as a manufacturing method of the melamine cyanurate containing the said carboxylic acid amide, Although it can select suitably according to the objective, For example, the method of surface-treating melamine cyanurate using a fatty acid is mentioned suitably. Can be.

There is no restriction | limiting in particular as said surface treatment method, It can select from a well-known method suitably, For example, the method of mixing and stirring the said melamine cyanurate and the said fatty acid is mentioned.

Moreover, when surface treatment of the said melamine cyanurate is used using the said fatty acid, it is thought that the amino group in the said melamine cyanurate reacts and converts into an amide compound, as shown in following formula (1). For this reason, the presence of the carboxylic acid amide can be confirmed by analyzing using the pyrolysis gas chromatography (Py-GC-MS).

-NH ₂ + R-COOH-> R-CONH -... Formula (1)

There is no restriction | limiting in particular as said fatty acid, According to the objective, it can select suitably, For example, lauric acid, isostearic acid, stearic acid, palmitic acid, oleic acid, linolenic acid, etc. are mentioned. These may be used individually by 1 type and may use 2 or more types together. Among these, lauric acid is preferable from the viewpoint of high hydrophobicity and good dispersibility.

There is no restriction | limiting in particular as content of the melamine cyanurate containing the said carboxylic acid amide, Although it can select suitably according to the objective, it is 35 mass parts-150 mass parts with respect to 106.1 mass parts of total amounts of an epoxy resin and an acrylic resin. .

--- Red ---

It is preferable that the said flame retardant further contains red phosphorus in addition to the melamine cyanurate containing the said carboxylic acid amide. In this case, it is advantageous at the point which can further improve the flame retardance of the said magnetic sheet.

There is no restriction | limiting in particular as said red phosphorus, A commercial item may be sufficient and it may be what synthesize | combined suitably, However, It is preferable that the surface is coated by the point which is excellent in moisture resistance, does not spontaneously ignite at the time of mixing, and is good in safety. Do.

As a red phosphorus coated with the said surface, the thing which surface-treated the surface of red phosphorus using aluminum hydroxide is mentioned, for example.

There is no restriction | limiting in particular as content of the said red phosphorus, Although it can select suitably according to the objective, It is preferable that they are 6 mass parts-20 mass parts with respect to 106.1 mass part of total amounts of an epoxy resin and an acrylic resin.

If the said content is less than 6 mass parts, a flame retardance improvement effect may not be acquired, and when it exceeds 20 mass parts, the total amount of the said magnetic component and the said flame retardant with respect to the said resin component will become large, and the said magnetic component will be based on the said resin component. In addition to making it difficult to connect and fix the flame retardant, the content ratio of the magnetic component in the magnetic sheet may decrease, and the permeability may decrease.

Silane Coupling Agent

As described in paragraphs 0007 to 0010 of JP2002-212537A, the silane coupling agent functions together with an aluminum chelating agent to initiate cationic polymerization of a thermosetting resin (e.g., a thermosetting epoxy resin). Has Therefore, by using together a small amount of such a silane coupling agent, the effect of promoting hardening of an epoxy resin can be acquired. As such a silane coupling agent, it has 1-3 lower alkoxy groups in a molecule | numerator, group which is reactive with the functional group of a thermosetting resin in a molecule | numerator, for example, a vinyl group, a styryl group, acryloyloxy group, a methacryloyloxy group, You may have an epoxy group, an amino group, a mercapto group, etc. Moreover, since the latent hardening | curing agent of this invention is a cationic type hardening | curing agent, the coupling agent which has an amino group and a mercapto group can be used when an amino group and a mercapto group do not substantially capture a cationic species generate | occur | produced.

Specific examples of such a silane coupling agent include vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-styryltrimethoxysilane, and γ-methacryloxypropyltrimethoxy Silane, γ-acryloxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane , N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl- (gamma) -aminopropyl trimethoxysilane, (gamma)-mercaptopropyl trimethoxysilane, (gamma)-chloropropyl trimethoxysilane, etc. are mentioned.

When using a small amount of silane coupling agents together, when the content is too small, the addition effect cannot be desired, and when too large, since the effect of the polymerization terminating reaction by the silanolate anion which arises from a silane coupling agent arises, it is an aluminum chelate system It is 1 mass part-300 mass parts with respect to 100 mass parts of latent hardeners, Preferably they are 1 mass part-100 mass parts.

In the magnetic sheet composition of the present invention, an aluminum chelate latent curing agent, a silanol compound represented by formula (A) or an alkoxysilane compound, an epoxy resin, an acrylic resin, a magnetic component, and additional additives as necessary, may be uniformly prepared according to a conventional method. It can manufacture by mixing and stirring. In addition, the silanol compound or alkoxysilane compound represented by Formula (A) to an aluminum chelate latent curing agent is not mixed with the aluminum chelate latent curing agent and the silanol compound or alkoxysilane compound represented by Formula (A), respectively. You may use the thing impregnated with. As an impregnation method, the method of disperse | distributing and mixing an aluminum chelate latent hardening | curing agent for several hours in the alcohol (ethanol, propanol, etc.) solution of the silanol compound or alkoxysilane compound represented by Formula (A) is mentioned. After mixing, the liquid may be pulled out of the liquid and dried.

There is no restriction | limiting in particular as content of the said other components, According to content of the said aluminum chelate latent hardening | curing agent, the said silanol compound, or the alkoxysilane compound, the said epoxy resin, the said acrylic resin, and the said magnetic component, it can determine suitably. .

Thus, since the magnetic sheet composition of this invention uses the aluminum chelate latent hardening | curing agent as a hardening | curing agent, it is excellent in storage stability irrespective of a single type. In addition, regardless of whether it contains an epoxy resin that could not be cured sufficiently with an aluminum chelate latent curing agent, the magnetic sheet composition can be cationicly polymerized by low-temperature hardening because it contains a specific silanol having high granularity. Silanol is a very unstable substance, trimethylsilanol and the like are easily coupled with moisture in the air to deactivate the curing activity, but since a bulky phenyl group is present, the addition reaction of the silanolate anion to the epoxy is suppressed. Thereby suppressing the progress of the side reaction and avoiding the coupling reaction).

Moreover, the mixing property at the time of mix | blending an aluminum chelate latent hardener and a magnetic component (for example, aluminum alloy) is good, and application | coating can be performed favorably.

(Magnetic sheet)

The magnetic sheet of the present invention has a magnetic layer containing the magnetic sheet composition of the present invention, and further has other layers selected appropriately as necessary.

-Magnetic layer-

The magnetic layer has a function of reducing unnecessary electromagnetic waves emitted from an electronic device and suppressing electromagnetic interference caused by interference of unnecessary electromagnetic waves in the electronic device.

There is no restriction | limiting in particular as thickness of the said magnetic layer, Although it can select suitably according to the objective, From the point which can obtain a high permeability, it is preferable that it is thick and 25 micrometers-500 micrometers are preferable.

If the thickness is less than 25 μm, the permeability is low, and if it exceeds 500 μm, the permeability is unsuitable for narrow areas, and the thickness of the electronic device is not obeyed in recent years. It may become small. Moreover, when the said thickness becomes 70 micrometers or less, there exists a tendency for permeability to fall rapidly.

-Other floors-

As said other layer, there is no restriction | limiting in particular, unless the effect of this invention is impaired, According to the objective, it can select suitably, For example, an uneven | corrugated forming layer etc. are mentioned.

-Uneven layer-

The said uneven | corrugated forming layer has a function which peels the said magnetic sheet from the member which contacts this, for example in an electronic device at the time of use of the said magnetic sheet of this invention.

There is no restriction | limiting in particular about the structure, thickness, material (material) as said uneven formation layer, According to the objective, it can select suitably.

As said structure, a single layer structure may be sufficient and a laminated structure may be sufficient.

As said thickness, 2 micrometers-100 micrometers are preferable.

When the said thickness is less than 2 micrometers, workability may worsen. When it exceeds 100 micrometers, heat may be hardly transmitted to the said magnetic layer at the time of a hot press, and reliability may fall.

Synthetic resin is mentioned as said material, For example, polyethylene terephthalate (PET) is mentioned suitably.

Although the said uneven | corrugated formation layer may be a commercial item, and may be produced suitably, As said commercial item, Matt processed PET ("Lumirror X44- # 25"; Toray Corporation make), Matt processed PET ("Lumirror" 44- # 38 ”; manufactured by Toray Corporation), PET (" Mburet "; Unitika Co., Ltd.), non-silicone peeling PET (" Fluoroju RL "; Mitsubishi Jushi) And silicone peeling treatment PET (&quot; 25GS &quot;; manufactured by Lintec Co., Ltd.). Letters printed with the concave-convex formation layer may be used. The printing surface of the letter may be a surface in contact with the magnetic layer, or may be a surface (opposite surface) not in contact with the magnetic layer.

- use -

There is no restriction | limiting in particular as a usage method of the said magnetic sheet of this invention, According to the objective, it can select suitably, For example, the said magnetic sheet is cut | disconnected to a desired size, and this magnetic layer side is cut into the noise source of an electronic device. Can be placed in close proximity.

- Usage -

The magnetic sheet of the present invention can be suitably used for an electronic device having an IC tag function such as an electronic noise suppressor, an electromagnetic wave absorber, a magnetic shield material, and a radio frequency identification (RFID), a non-contact IC card, and the like. It can use suitably for the mobile telephone which has.

The magnetic sheet of this invention can be manufactured by low temperature short time press, and can shorten a tact time. In addition, a sulfonium salt is used for the conventional cation hardening | curing agent, and after hardening, although there existed the peculiar smell of a sulfonium salt, the aluminum chelate latent hardener is odorless, and the working environment at the time of manufacture of a magnetic sheet improves, and it is a bad smell It can also be used for sensitive sites (eg, in-vehicle use).

Unlike the conventional magnetic sheet, the magnetic sheet of the present invention does not have to have an adhesive layer. If the adhesive layer is not provided, failure of the electronic device due to leakage of the pressure sensitive adhesive, which occurs during use at high temperature in the electronic device, can be prevented. Moreover, compared with the conventional magnetic sheet, since the thickness of a magnetic layer can be provided as much as the thickness of the said adhesion layer, specific gravity is large and permeability is high.

There is no restriction | limiting in particular as a manufacturing method of the said magnetic sheet of this invention, Although it can select suitably according to the objective, According to the manufacturing method of the magnetic sheet of this invention below, it can manufacture suitably.

(Method for producing magnetic sheet)

The manufacturing method of the magnetic sheet of this invention includes the magnetic layer formation process and the shape transfer process at least, and contains the other process further suitably selected as needed.

<Magnetic layer forming process>

The magnetic layer forming step comprises a magnetic sheet composition comprising at least an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component. It is a process of forming and forming a magnetic layer.

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different).

In addition, the detail of the said aluminum chelate latent hardening | curing agent, the silanol compound or alkoxysilane compound represented by said Formula (A), the said epoxy resin, the said acrylic resin, the said magnetic component, and the said other component is as mentioned above. However, as for the said epoxy resin and the said acrylic resin, it is preferable that it is an uncured state before the heat press mentioned later. Here, when hardening advances before a hot press, compression of the said magnetic layer is not fully performed and permeability cannot be enlarged. In addition, when the hardened magnetic layer is compressed, distortion remains, and when repeatedly exposed in a room temperature, a high temperature, a high temperature, and a high humidity environment, the thickness changes in a direction in which the thickness becomes thick, or the magnetic properties decrease. In contrast, when the epoxy resin and the acrylic resin before the hot press are in an uncured state, occurrence of these problems is suppressed.

Preparation of the said magnetic sheet composition can be performed by adding and mixing the said magnetic component, the said aluminum chelate latent hardening | curing agent, the silanol compound represented by said Formula (A), or the alkoxysilane compound to the said epoxy resin and the said acrylic resin. have.

Molding of the magnetic sheet composition can be performed by applying and drying the magnetic sheet composition on a substrate, for example.

There is no restriction | limiting in particular as said base material, Although it can select suitably according to the objective, The polyester film (peeled PET) etc. which performed the peeling process are mentioned suitably from the point which can peel easily the formed said magnetic layer.

In addition, as said base material, matte PET, PET which is not peeling-processed, non-silicone peeling-processed PET (the surface in which a magnetic layer is formed is not peeled), and silicone peeling process PET (the surface in which a magnetic layer is formed is not peeled). No) may be used.

According to the above process, the said magnetic sheet composition is shape | molded and the said magnetic layer is formed.

<Shape Transfer Process>

In the shape transfer step, the surface shape of the transfer material is formed by heating and pressing the uneven formation layer and the transfer material on one surface in the thickness direction of the magnetic layer in this order from the magnetic layer side. It transfers to the surface of an uneven | corrugated formation layer and the said magnetic layer, and is a process of joining the said uneven | corrugated formation layer and said magnetic layer.

-Uneven layer-

There is no restriction | limiting in particular about the structure, thickness, material (material) as said uneven | corrugated formation layer, According to the objective, it can select suitably, The detail is as mentioned above.

There is no restriction | limiting in particular as a surface state of the said uneven | corrugated formation layer, The surface treatment may be given to one surface in the thickness direction, and the surface treatment may not be given, but mat treatment and a silicone resin are not used. It is preferable that the peeling process etc. which are not performed are performed. In these cases, sliding property improves compared with the case where no surface treatment is given. In addition, in the case of these surface treatments, since the silicone resin is not used, the silicone oligomers do not bleed out under high temperature to high temperature and high humidity environments, and are suitable for use in electronic devices.

As said mat process, there is no restriction | limiting in particular as long as the surface of the said uneven | corrugated forming layer can be roughened, It can select according to the objective, For example, a sand mat process, a chemical mat process, a surface embossing process, etc. are mentioned. By these processes, unevenness | corrugation is formed in the surface of the said uneven | corrugated formation layer, and a sliding property is improved.

-Transfer Material-

There is no restriction | limiting in particular about the structure, thickness, and a material (material) as said transfer material, Although it can select suitably according to the objective, The thing which has unevenness | corrugation on the surface, and is excellent in breathability is preferable. In this case, when the unevenness of the surface of the transfer material is transferred to the unevenness forming layer, the unevenness is formed on the surface of the unevenness forming layer, and the sliding property is improved.

As said structure, a single layer structure may be sufficient and a laminated structure may be sufficient.

As said thickness, 25 micrometers-200 micrometers are preferable.

When the said thickness is less than 25 micrometers, the magnetic sheet which improved sliding property may not be obtained, and when it exceeds 200 micrometers, heat may be hardly transmitted to the said magnetic layer at the time of the said hot press, and reliability may fall. .

As said material, paper, synthetic fiber, a natural fiber, etc. are mentioned, for example.

Although the said transfer material may be a commercial item, and may be produced suitably, As said commercial item, it is good quality paper ("OK Prince good quality 70"; Oji Seiji Co., Ltd. product), a cushion paper ("TF190"; Toyo fiber ( Co., Ltd.), nylon mesh ("N-NO.110S"; Tokyo Screen Co., Ltd.), cotton cloth ("Kanakin No. 3"; Japan Standards Association), base paper for adhesives ("SO paper 18G"; die) Fuku Seiji Co., Ltd.), double-sided release paper ("100GVW (high smooth surface)"; Oji Seiji Co., Ltd.), double-sided release paper ("100GVW (low smooth surface)"; Oji Shiji Co., Ltd.) Etc. can be mentioned.

Stacked layout

There is no restriction | limiting in particular as a method of the said laminated arrangement as long as the said uneven | corrugated formation layer and the said transfer material are laminated | stacked in this order from the said magnetic layer side on one surface in the thickness direction of the said magnetic layer, According to the objective, it selects suitably Although it is possible, it is preferable to further laminate | stack a peeling layer and the said transfer material in this order from the said magnetic layer side to the other surface in the thickness direction of the said magnetic layer. By interposing the release layer, the other surface of the magnetic layer is protected at the time of a heat press described later to prevent adhesion with the transfer material, and the transfer material is combined with the release layer after the heat press. It can peel easily from the said magnetic layer. Moreover, although the surface shape of the said transfer material is also transferred to the surface of the said magnetic layer located in the said peeling layer side, the bubble which exists in the said resin composition in the said magnetic layer tends to come out easily, and the reliability of the magnetic sheet obtained improves. . When the transfer material on the release layer side is not used, the magnetic permeability of the magnetic sheet can be improved.

There is no restriction | limiting in particular as said peeling layer as long as it has a function which prevents adhesion of the other surface in the thickness direction of the said magnetic layer and the said transfer material at the time of the said hot press, Although it can select suitably according to the objective, Since it can peel easily from the said magnetic layer after a hot press, the polyester film (peeling PET) with which the surface was peeled off is preferable.

-Heat press-

There is no restriction | limiting in particular as a method of the said hot press, According to the objective, it can select suitably, For example, as shown in FIG. 1, using the said magnetic layer, the said uneven | corrugated formation layer, and the said transfer material as a laminated body, these were laminated from both sides. It can carry out by heating and pressurizing between sandwiching presses.

By the said heat press, the surface shape (uneven | corrugated shape) of the said transfer material is transferred to the surface of the said uneven | corrugated formation layer and the said magnetic layer, and the said uneven | corrugated formation layer and said magnetic layer are directly bonded, even if an adhesive etc. are not used.

There is no restriction | limiting in particular as conditions of the said hot press, According to the objective, it can select suitably, As press temperature, for example, 80 degreeC-190 degreeC is preferable, As press pressure, 5 MPa-20 MPa are preferable, for example. As press holding time, 1 minute-20 minutes are preferable, for example.

According to the above process, the surface shape of the said transfer material is transferred to the surface of the said uneven | corrugated formation layer and the said magnetic layer, and the said uneven | corrugated formation layer and said magnetic layer are joined. As a result, the magnetic sheet which consists of the said magnetic layer and the said uneven | corrugated forming layer can be obtained.

The magnetic sheet thus obtained is excellent in sliding property because the surface shape (surface irregularities on the surface) of the transfer material is transferred to the surface of the unevenness forming layer and roughened.

According to the manufacturing method of the magnetic sheet of the present invention, since the surface shape of the transfer material is transferred to the surface of the unevenness forming layer and the magnetic layer by the heat press, the surface of the unevenness forming layer is roughened, and the sliding property Can be improved.

Moreover, since the said uneven | corrugated forming layer and the said magnetic layer are directly bonded by the said heat press, an adhesive layer is unnecessary, and a magnetic sheet can be manufactured efficiently simply and at low cost.

Hereinafter, although the Example of this invention is described, this invention is not limited to a following example at all.

(Example 1)

-Preparation of aluminum chelate latent curing agent (1)-

3 liters with 800 parts by mass of distilled water, 0.05 parts by mass of surfactant (Neulex RT, Nihon Yushi Co., Ltd.), and 4 parts by mass of polyvinyl alcohol (PVA-205, Kuraray) as a dispersant. Into the interfacial polymerization vessel of and mixed uniformly. To this mixed solution, 100 parts by mass of a 24% isopropanol solution (aluminum chelate D, Kawaken Chemical Co., Ltd.) of aluminum monoacetylacetonate bis (ethylacetoacetate), and methylene diphenyl-4,4'- 70 parts by mass of a trimethylolpropane (1 mole) adduct of diisocyanate (3 moles) (D-109, Mitsuda Keda Chemical Co., Ltd.), 30 parts by mass of divinylbenzene (Merck Co., Ltd.), and a radical polymerization initiator (Ferro 1 L, Nihon Oil Co., Ltd.) The oily solution which melt | dissolved 0.30 mass part in 100 mass parts of ethyl acetate was thrown in, and it superposed | polymerized at 80 degreeC for 6 hours after emulsion mixing with a homogenizer (10,000 rpm / 5 minutes).

After completion of the reaction, the polymerization reaction solution was allowed to cool to room temperature, and the interfacial polymerization particles were separated by filtration by filtration and naturally dried to obtain 100 parts by mass of a spherical aluminum chelate latent curing agent (1) having a particle size of about 2 µm.

-Production of magnetic sheet-

First, 83 mass parts of acrylic resins ("SG80H-3"; Nagase ChemteX Co., Ltd. product, number average molecular weight 150,000, weight average molecular weight 350,000), 270 mass parts of toluene and 120 mass parts of ethyl acetate as solvents, cresol novolak 23.1 parts by mass of a type polyfunctional epoxy resin (“Epicoat 1031S” manufactured by Japan Epoxy Resin Co., Ltd.), 6.21 parts by mass of the produced aluminum chelate latent curing agent (1), and triphenylsilanol (TPS) as a silanol compound (Tokyo Kasei Co., Ltd. product) 0.69 mass part was dissolved, and the resin composition was prepared. 550 mass parts of flat magnetic powder ("JEM-S"; Mitsubishi Material) make) as this magnetic component was added to this, these were mixed, and the magnetic sheet composition was prepared.

Next, the obtained magnetic sheet composition was subjected to a bar coater on a polyester film (peeled PET) (&quot; 38GS &quot;; Lintec manufactured, 38 µm thick) on which the peeling treatment was performed on the surface as the base material (uneven forming layer). It applied so that thickness might be 100 micrometers-200 micrometers (The magnetic sheet composition was apply | coated to the surface to which it peeled).

Subsequently, it dried at room temperature for 10 minutes, and further dried at 60 degreeC for 10 minutes, cut | disconnected peeling PET in which the layer (magnetic layer) containing the magnetic sheet composition was formed in the surface which has been peeled off to 250 mm x 250 mm, and peels. Three sheets of peeling PET in which the magnetic layer of 250 mm x 250 mm was formed in the process surface were obtained.

Next, the obtained magnetic sheet composition was subjected to a bar coater on a polyester film (peeled PET) (&quot; 38GS &quot;; Lintec manufactured, 38 µm thick) on which the peeling treatment was performed on the surface as the base material (uneven forming layer). It applied so that thickness might be 100 micrometers-200 micrometers (The magnetic sheet composition was apply | coated to the surface which is not peeled).

Subsequently, the resultant was dried at room temperature for 10 minutes, further dried at 60 ° C. for 10 minutes, and cut off the peeled PET having a layer (magnetic layer) containing a magnetic sheet composition on a surface not subjected to peeling to 250 mm × 250 mm, One piece of peeling PET in which the magnetic layer of 250 mm x 250 mm was formed in the surface which was not peeled off was obtained.

Next, peeling PET was peeled from the magnetic layer with respect to two peeling PET in which the magnetic layer of 250 mmx250 mm was formed in the surface by which peeling process was carried out, and two magnetic layers of 250 mmx250 mm were obtained. Next, two magnetic layers cut to 250 mm x 250 mm are piled up on the magnetic layer side of the peeling PET in which the magnetic layer of 250 mm x 250 mm is formed on the surface to which the peeling process was carried out, and further, 250 to the surface which has not been peeled One peeled PET in which a magnetic layer of mm x 250 mm was formed (overlaid so that the magnetic layer and the magnetic layer faced each other) was sandwiched with peeling PET, and peeled PET in which four magnetic layers were laminated was also obtained.

Subsequently, on both sides of the peeling PET disposed to sandwich the four stacked magnetic layers, the above-mentioned cushioning material was made of good quality paper ("OK Prince good quality 70"; Oji Sage Co., Ltd. thickness, 100 micrometers in thickness, 6.2 second of Beck smoothness /). mL) were stacked. Then, using a vacuum press (manufactured by Kitagawa Seiki Co., Ltd.), press holding temperature 170 ° C., press holding time (time held at press holding temperature) for 5 minutes, press time (90 ° C. to press holding temperature was reached). Time until the temperature is lowered to 90 ° C.) for 38 minutes, and heat-pressing with a press plate through the above-mentioned cushioning material under conditions of a press pressure of 9 MPa, and peeling PET (peeling PET having a magnetic layer formed on the surface to be peeled). One sheet was peeled from four stacked magnetic layers to obtain a magnetic sheet.

(Examples 2 to 24)

-Production of magnetic sheet-

In Example 1, the compounding quantity of the said aluminum chelate latent hardener (1), the compounding quantity of the said triphenyl silanol (TPS), the said press holding temperature, the said press holding time, and the said press time is shown in a table Except having changed as shown to 1-4, it carried out similarly to Example 1, and produced the magnetic sheet.

(Example 25)

-Production of magnetic sheet-

In Example 17, triphenylsilane (TPS) (manufactured by Tokyo Kasei Co., Ltd.) as the silanol compound was converted to diphenyldimethoxysilane (KBM-202SS) as the alkoxysilane compound (Shin-Etsu Chemical Co., Ltd.). A magnetic sheet was produced in the same manner as in Example 17 except that the present invention was manufactured by the present invention.

(Example 26)

-Production of magnetic sheet-

In Example 17, the triphenylsilanol (TPS) (manufactured by Tokyo Kasei Co., Ltd.) as the silanol compound was replaced with diphenylsilane diol (DPSD) (manufactured by Tokyo Kasei Co., Ltd.). A magnetic sheet was produced in the same manner as in Example 17 except for this.

(Examples 27 to 31)

-Production of magnetic sheet-

In Example 17, the flat magnetic powder ("JEM-S"; manufactured by Mitsubishi Material) as the magnetic component was replaced with flat magnetic powder ("EMS10"; manufactured by Mitsubishi Material). And the magnetic sheet was produced like Example 17 except having changed the compounding quantity of this flat magnetic powder ("EMS10"; Mitsubishi Material Co., Ltd. product) as shown in Table 5.

(Example 32)

-Production of magnetic sheet-

In Example 1, except for changing the compounding quantity of the said aluminum chelate latent hardener (1), and the compounding quantity of the said triphenyl silanol (TPS) as shown in Table 9, it carried out similarly to Example 1, and it was magnetic The sheet was produced.

(Example 33)

-Production of magnetic sheet-

In Example 27, the magnetic sheet was produced like Example 27 except having added the melamine cyanurate containing red phosphorus and carboxylic acid amide in the quantity shown in Table 9.

(Example 34)

-Production of magnetic sheet-

In Example 33, the flat magnetic powder ("EMS10"; manufactured by Mitsubishi Material Co., Ltd.) as the magnetic component is replaced with flat magnetic powder ("JEM-S"; manufactured by Mitsubishi Material). And the magnetic sheet was produced like Example 33 except having changed the compounding quantity of this flat magnetic powder ("JEM-S"; Mitsubishi Material Co., Ltd. product) as shown in Table 9.

(Reference Examples 1 to 7)

-Production of magnetic sheet-

In Example 1, at least any one of the compounding amount of the aluminum chelate latent curing agent (1), the compounding amount of the triphenylsilanol (TPS), the press holding temperature, the press holding time, and the press time, Except having changed as shown in Table 6, it carried out similarly to Example 1, and produced the magnetic sheet.

(Comparative Example 1)

-Production of magnetic sheet-

In Example 10, 3.45 parts by mass of the produced aluminum chelate latent curing agent (1) and 3.45 parts by mass of triphenylsilanol (TPS) (manufactured by Tokyo Kasei Co., Ltd.) as the silanol compound were sulfonium-based (antimony System) A magnetic sheet was produced in the same manner as in Example 10 except that the cationic curing agent (Sunade SI-100L; manufactured by Sanshin Kagaku Kogyo Co., Ltd.) was changed to 6.9 parts by mass.

(Comparative Example 2)

-Production of magnetic sheet-

In Comparative Example 1, a sulfonium-based (antimony) cationic curing agent (Sunade SI-100L; manufactured by Sanshin Kagaku Kogyo Co., Ltd.) was used as a sulfonium-based (antimony-based) cationic curing agent (Sunade SI-150; Sanshin Kagaku). A magnetic sheet was produced in the same manner as in Comparative Example 1 except for changing to Kogyo Co., Ltd.).

(Comparative Example 3)

-Production of magnetic sheet-

In Comparative Example 1, 6.9 parts by mass of a sulfonium-based (antimony) cationic curing agent (Sunade SI-100L; manufactured by Sanshin Kagaku Kogyo Co., Ltd.) is an imidazole series curing agent (`` Novacure HX3748 ''; Asahi Kasei Chemical Co., Ltd.) ) Production) A magnetic sheet was produced in the same manner as in Comparative Example 1 except that the amount was changed to 1.0 parts by mass.

(Comparative Examples 4 to 8)

-Production of magnetic sheet-

In the comparative example 3, at least any one of the compounding quantity of the imidazole series hardening | curing agent ("Novacure HX3748"; Asahi Kasei Chemical Co., Ltd. product), the said press holding temperature, the said press holding time, and the said press time is shown in Tables 7- Except having changed as shown in 8, it carried out similarly to the comparative example 3, and produced the magnetic sheet.

(Comparative Example 9)

-Production of magnetic sheet-

In Example 17, triphenylsilanol (TPS) (manufactured by Tokyo Kasei Kogyo Co., Ltd.) as the silanol compound was prepared by γ-glycidoxypropyltrimethoxysilane (A187) (momentive performance mud). A magnetic sheet was produced in the same manner as in Example 17 except that the product was changed to Reales Japan Co., Ltd.).

(Comparative Example 10)

-Production of magnetic sheet-

In Example 17, triphenylsilane (TPS) (manufactured by Tokyo Kasei Co., Ltd.) as the silanol compound was substituted with phenyltrimethoxysilane (KBM-103) (manufactured by Shin-Etsu Chemical Co., Ltd.). A magnetic sheet was produced in the same manner as in Example 17 except for changing to.

(Comparative Example 11)

-Production of magnetic sheet-

In Example 1, except that the produced aluminum chelate latent curing agent (1) and triphenylsilol (TPS) (produced by Tokyo Kasei Co., Ltd.) as a silanol compound were not added. In the same manner, a magnetic sheet was produced.

The following evaluation was performed about the obtained magnetic sheet.

[Permeability]

First, a ring-shaped sample (magnetic layer sample) which was drawn to an outer diameter of 7.05 mm and an inner diameter of 2.945 mm was produced. The wire was wound 5 turns and soldered to the terminal. Here, the length from the base of the terminal to the bottom of the ring-shaped sample (magnetic layer sample) was set to 20 mm. The inductance and resistance value at 1 MHz were measured using an impedance analyzer ("4294A" (manufactured by Agilent Technologies, Inc.)), and converted into permeability (permeability of the magnetic layer).

In addition, mu 'represents the real part of complex permeability.

The characteristic of μ 'varies depending on the purpose of use of the magnetic sheet. For example, in the case of improving communication of an RFID device, at a frequency of 20 MHz or less, high μ' and low μ '(imaginary part of complex permeability) It is preferable.

Moreover, the magnetic sheet of this invention is a magnetic sheet which can be used in the KHz-GHz band.

Reliability Test

-Thickness change-

First, the thickness (thickness which does not contain PET) of the magnetic layer in a magnetic sheet was measured. Subsequently, the magnetic sheet was placed in an oven, heated at 85 ° C./60% for 96 hours, the thickness of the magnetic layer (thickness not including PET) in the magnetic sheet after taking out from the oven was measured, and before and after heating. The change rate of the thickness (thickness which does not contain PET) of the magnetic layer in the magnetic sheet of was measured.

[Unpleasant smell]

About the obtained magnetic sheet, it was determined about the presence or absence of an unpleasant smell.

Corrosion Test

About 0.2 g of the magnetic sheet samples (with PET) obtained from Example 20 and Comparative Example 6, respectively, were placed in a measuring cup containing 50 mL of tap water, which was left in an oven set at 85 ° C / 85% for 30 hours. The magnetic sheet sample (having PET) was taken out and evaluated visually.

From the results of Tables 1 to 9, the magnetic sheets of Examples 1 to 31 produced using an aluminum chelate latent curing agent and the silanol compound or alkoxysilane compound represented by the above formula (A) are low-temperature-curable. It was found that no odor was generated and no corrosion occurred.

Regarding the combination of Examples 17, 25, 26 and Comparative Examples 9-10, the reliability test of the Example using the silanol compound or alkoxysilane compound represented by said Formula (A) was carried out in the preparation conditions of a magnetic sheet. It is understood from the fact that the thickness change rate in is smaller than the thickness change rate of the comparative example in which the silanol compound or the alkoxysilane compound represented by the formula (A) is not used.

In Comparative Example 6 using an imidazole series curing agent (Novacure), although a thickness change (0.79%) before and after a low reliability test was obtained, there was a problem that corrosion occurred, and sulfonium-based (antimony-based) In Comparative Examples 1 and 2 using a cationic curing agent, although the thickness change (0.39%, 0.80%) before and after the low reliability test was obtained, an unpleasant odor remained in the magnetic sheet after curing, so it was necessary to remove the unpleasant odor by heat treatment. There is a problem.

In addition, when imidazole series hardening | curing agent (novacure) is used as a hardening | curing agent, in order to obtain the thickness change before and behind a low reliability test, as shown in the comparative example 6, press holding temperature 170 degreeC, press holding time 10 minutes, press time 43 Although minutes are required, when using the aluminum chelate latent hardener and the silanol compound or alkoxysilane compound represented by said Formula (A), as shown in Example 24, press holding temperature 150 degreeC and press holding time 5 It was found that even in the press condition of the press time for 20 minutes, the change in thickness before and after the low reliability test can be obtained.

In addition, in Reference Examples 1-7, since press temperature was low and press time was short, hardening failure generate | occur | produced and the reliability test was bad.

The magnetic sheet of the present invention can be suitably used, for example, in an electronic device having an IC tag function such as an electronic noise suppressor, an electromagnetic wave absorber, a magnetic shield material, RFID, a non-contact IC card, and the like, and in particular, a cellular phone having an RFID function. It can be used suitably.

10: magnetic layer
20: uneven | corrugated forming layer
22: release layer
30: transfer material
40: laminate
50: press plate

Claims (9)

A magnetic sheet composition comprising an aluminum chelate latent curing agent, a silanol compound or an alkoxysilane compound represented by the following formula (A), an epoxy resin, an acrylic resin, and a magnetic component:

(Wherein m is either 2 or 3, and the sum of m and n is 4. Ar is an aryl group which may be substituted and R is either a hydrogen atom or a methyl group. When n is plural, R is May be the same or different). The magnetic sheet composition of claim 1, wherein Ar is a phenyl group. The magnetic sheet composition according to claim 1 or 2, wherein the silanol compound or the alkoxysilane compound is any one of triphenylsilanol, diphenylsilanediol, and diphenyldimethoxysilane. The aluminum according to any one of claims 1 to 3, wherein the aluminum chelate-based latent curing agent maintains the aluminum chelating agent in the porous resin obtained by interfacial polymerization of the polyfunctional isocyanate compound and radical polymerization of divinylbenzene. Magnetic sheet composition which is a latent curing agent. The magnetic component is 500 mass parts-1,250 mass parts with respect to 106.1 mass parts of total amounts of an epoxy resin and an acrylic resin, The aluminum chelate latent hardening | curing agent and a silanol compound, or any one of Claims 1-4. Magnetic sheet composition whose total amount of alkoxysilane compound is 2 mass parts-15 mass parts. The magnetic sheet composition according to any one of claims 1 to 5, wherein the total amount of the aluminum chelate latent curing agent and the silanol compound or the alkoxysilane compound is 6.9 parts by mass to 15 parts by mass. The magnetic substance according to any one of claims 1 to 6, wherein the mass ratio (aluminum chelate latent curing agent / silanol compound or alkoxysilane compound) of the aluminum chelate latent curing agent and the silanol compound or the alkoxysilane compound is 1.0 or less. Sheet composition. It has a magnetic layer containing the magnetic sheet composition of any one of Claims 1-7, The magnetic sheet characterized by the above-mentioned. A magnetic layer forming step of forming the magnetic layer by molding the magnetic sheet composition according to any one of claims 1 to 7,
After laminating and arrange | positioning an uneven | corrugated formation layer and a transfer material in this order from the said magnetic layer side in at least one surface in the thickness direction of the said magnetic layer, it heat-presses the surface shape of the said transfer material by the said uneven | corrugated formation layer and the said magnetic layer A shape transfer step of transferring the concave-convex formation layer and the magnetic layer while transferring to the surface of the film
Method of producing a magnetic sheet comprising a.

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