KR101831870B1 - Method for preparing conductive magnet composite sheet and antenna device - Google Patents

Abstract

The magnetic sheet according to the embodiment has excellent magnetic properties at the frequencies of NFC, WPC and MST, and has improved heat resistance characteristics. Further, the magnetic sheet is not only excellent in flexibility but also can contain a magnetic powder in a high content and can have excellent magnetic properties. Accordingly, the conductive magnetic composite sheet and the antenna element manufactured using the magnetic sheet can be usefully used for NFC, WPC, and MST applications.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a conductive magnetic composite sheet,

Embodiments relate to a method of manufacturing a conductive magnetic composite sheet that can be used in fields such as local communication, wireless charging, and magnetic security transmission, a method of manufacturing an antenna element, and a conductive composite sheet and an antenna element manufactured thereby.

Recently, mobile devices such as mobile phones, tablet PCs and notebook PCs have realized functions such as near field communication (NFC), wireless power consortium (WPC) and magnetic secure transmission (MST) Is mounted. However, there are other parts of the metal material inside the mobile device, and when an alternating magnetic field formed inside the device is applied to such a metal part, eddy current is generated, thereby deteriorating the performance of the antenna, .

In order to solve this problem, a high permeability ferrite sheet is attached to the other surface of a general circuit board (antenna) such as a polyimide substrate having an antenna pattern layer formed on one surface thereof and used as a composite antenna element. This is based on the principle that a magnetic body such as a ferrite sheet can focus the magnetic flux of the antenna to prevent magnetic field penetration into the metal surface and generation of eddy current, and to improve the operating characteristics.

Korean Patent Laid-Open Publication No. 2013-50633

When a magnetic sheet is bonded to a circuit board as an antenna element and mounted in a mobile device, the efficiency of the inner space of the mobile device, which is limited by mounting various components, is lowered. In addition, if adhesion between the circuit board and the magnetic sheet is poor, peeling may occur. If the adhesive layer is provided to prevent such peeling, another problem arises that the entire thickness of the antenna element becomes thick.

There is an attempt to fabricate an antenna element by using a magnetic sheet as a base layer, laminating a conductive foil on the magnetic sheet, and then forming an antenna pattern by etching. However, a general sintered ferrite sheet or a polymer- A step of forming an adhesive layer by applying an adhesive and further drying the adhesive layer is further required and the thinning of the thickness is hindered due to the adhesive layer and the magnetic properties are also deteriorated.

Accordingly, the embodiment provides a method for producing a conductive magnetic composite sheet and an antenna element having magnetic properties that can be used in a combined use of NFC, WPC, and MST, and having excellent interlayer bonding force without requiring an adhesive in a manufacturing process, To provide a conductive magnetic composite sheet and an antenna element manufactured by the method.

According to one embodiment, there is provided a magnetic recording medium comprising: a magnetic sheet including a magnetic powder and a thermosetting binder resin; Laminating the magnetic sheet and the first conductive foil; And curing the binder resin by applying heat and pressure to the obtained laminate to bond the first conductive foil and the magnetic sheet while the binder resin is cured. do.

According to another embodiment, there is provided a magnetic recording medium comprising: a magnetic sheet including a magnetic powder and a thermosetting binder resin; Stacking the first conductive foil, the magnetic sheet and the second conductive foil in order; And curing the binder resin by applying heat and pressure to the resulting laminate and bonding the first conductive foil, the magnetic sheet and the second conductive foil while the binder resin is cured. A method of manufacturing a sheet is provided.

According to another embodiment, there is provided a magnetic sheet comprising: a magnetic sheet including a magnetic powder and a thermosetting binder resin; And a first conductive foil directly bonded to one surface of the magnetic sheet.

According to another embodiment, there is provided a magnetic recording medium comprising: a magnetic sheet including a magnetic powder and a thermosetting binder resin; Laminating the magnetic sheet and the first conductive foil; Curing the binder resin by applying heat and pressure to the resulting laminate, and bonding the first conductive foil and the magnetic sheet with the binder resin cured; And etching the first conductive foil to form a first antenna pattern.

According to another embodiment, there is provided a magnetic sheet comprising: a magnetic sheet including a magnetic powder and a thermosetting binder resin; And a first antenna pattern directly bonded to one surface of the magnetic sheet.

The conductive magnetic composite sheet according to the embodiment has excellent magnetic properties at the frequencies of NFC, WPC and MST and is excellent in interlayer bonding force between the magnetic sheet and the conductive foil. Therefore, the conductive magnetic composite sheet according to the embodiment can be applied to various environments such as high temperature heat treatment The interlayer delamination may not occur even if it changes.

Particularly, in the conductive magnetic composite sheet, a magnetic sheet containing a semi-cured or uncured thermosetting resin is laminated with a conductive foil, and the thermosetting resin is cured by heat and pressure, so that the magnetic sheet and the conductive foil They can be laminated with excellent bonding strength to each other.

Accordingly, a step of applying an adhesive to form an adhesive layer and drying it is not necessary, so that the efficiency and economical efficiency of the process can be improved.

Further, the thinness of the entire thickness can be achieved by the absence of the adhesive layer, and the deterioration of the magnetic properties due to the adhesive layer can be prevented.

Further, the magnetic sheet is not only excellent in flexibility but also can contain a magnetic powder in a high content and can have excellent magnetic properties.

Accordingly, the conductive composite sheet and the antenna element manufactured by the method according to the embodiment can be usefully used for NFC, WPC, and MST applications.

1 shows a cross section of a magnetic sheet according to an embodiment.
2 is a cross-sectional view of the conductive magnetic composite sheet according to the embodiment.
FIG. 3 shows a process of manufacturing a magnetic sheet according to an embodiment.
FIG. 4 illustrates a process of manufacturing the conductive magnetic composite sheet according to the embodiment.
5 and 6 show the roll-to-roll process and the batch process, respectively.
7 shows a cross-sectional view of an antenna element according to an embodiment.
8-10 illustrate plan views of an antenna element according to an embodiment. (Of the patterns, the black pattern is the front pattern, the hatched pattern is the back pattern, and the circle is the via.
11A and 11B are plan views showing a plan view and a cross-sectional view of the antenna element according to the embodiment.
12A to 12C show a process of manufacturing the antenna element according to the embodiment.
FIGS. 13 and 14 are diagrams schematically showing that the antenna element according to the embodiment transmits / receives signals to / from an external terminal.
Fig. 15 shows heat treatment conditions at the time of the reflow test.

In the description of the embodiments, in the case where each layer, foil or sheet is described as being formed "on" or "under" of each layer, foil or sheet, Quot; and "under " include both being formed" directly "or" indirectly "through" other elements ". In addition, the upper or lower reference of each component is described with reference to the drawings. In addition, sizes, intervals, and the like may be exaggeratedly displayed for the sake of clarity in the accompanying drawings, and details obvious to those skilled in the art may be omitted.

1 shows a cross section of a magnetic sheet according to an embodiment.

The magnetic sheet 100 includes a magnetic powder 110 and a binder resin 120.

That is, the magnetic sheet 100 may be a polymeric magnetic sheet (PMS). Specifically, the magnetic sheet 100 may be an unfired cured sheet containing the magnetic powder 110 and the binder resin 120. [ The magnetic sheet 100 may be a flexible magnetic sheet.

The magnetic sheet (100) contains a magnetic powder (110).

The magnetic powder may be an oxide magnetic powder such as ferrite (Ni-Zn type, Mg-Zn type, Mn-Zn type ferrite, etc.); Metal magnetic powders such as permalloy, sendust, Fe-Si-Cr alloys and Fe-Si-nanocrystals; Or a mixed powder thereof. For example, the magnetic powder may be a sandstone powder having an Fe-Si-Al alloy composition.

As a specific example, the magnetic powder may have a composition represented by the following formula (1).

[Chemical Formula 1]

Fe _1-abc Si _a X _b Y _c

In this formula,

X is Al, Cr, Ni, Cu, or a combination thereof;

Y is Mn, B, Co, Mo, or a combination thereof;

0.01? A? 0.2, 0.01? B? 0.1, and 0? C? 0.05.

The particle size of the magnetic powder may range from about 3 nm to about 1 mm. More specifically, the particle size of the magnetic powder may be in the range of about 1 to 300 mu m, about 1 to 50 mu m, or about 1 to 10 mu m. When the average particle diameter of the magnetic powder is within the above-described preferable range, it is possible to prevent short-circuiting when vias are formed in the magnetic sheet while exhibiting sufficient magnetic properties.

As the binder resin 120, a curable resin may be used. Specifically, the binder resin may include a photocurable resin, a thermosetting resin, and / or a high heat-resistant thermoplastic resin, and may preferably include a thermosetting resin.

As the resin that can be cured and exhibit adhesiveness, one or more functional groups or sites capable of being cured by heat such as a glycidyl group, an isocyanate group, a hydroxyl group, a carboxyl group, an amide group, or the like; Or at least one functional group or moiety capable of being cured by an active energy such as an epoxide group, a cyclic ether group, a sulfide group, an acetal group or a lactone group Can be used. Such a functional group or moiety may be, for example, an isocyanate group (-NCO), a hydroxy group (-OH), or a carboxyl group (-COOH).

Specifically, examples of the curable resin include, but are not limited to, a polyurethane resin, an acrylic resin, a polyester resin, an isocyanate resin or an epoxy resin having at least one functional group or moiety as described above.

According to one embodiment, the binder resin may include a polyurethane resin, an isocyanate curing agent, and an epoxy resin.

The polyurethane resin may include repeating units represented by the following general formulas (2a) and (2b).

[Chemical Formula 2b]

In this formula,

R ₁ and R ₃ are each independently a C _1-5 alkylene group, urea or ether group;

R ₂ and R ₄ are each independently a C _1-5 alkylene group;

Wherein each C _1-5 alkylene group has one or more substituents selected from the group consisting of halogen, cyano, amino and nitro.

The polyurethane resin may contain the repeating unit represented by the formula (2a) and the repeating unit represented by the formula (2b) in a molar ratio of 1:10 to 10: 1.

The polyurethane resin may have a number average molecular weight in the range of about 500 to 50,000 g / mol, in the range of about 10,000 to 50,000 g / mol, or in the range of about 10,000 to 40,000 g / mol.

The isocyanate-based curing agent may be an organic diisocyanate.

For example, the isocyanate-based curing agent may be an aromatic diisocyanate, an aliphatic diisocyanate, an alicyclic diisocyanate, or a mixture thereof.

The aromatic diisocyanate may be, for example, a diisocyanate having 1 to 2 C _6-20 aryl groups, specifically 1,5-naphthalene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4 ' -Diphenyl-dimethylmethane diisocyanate, 4,4'-benzyl isocyanate, dialkyl-diphenylmethane diisocyanate, tetraalkyl-diphenylmethane diisocyanate, 1,3-phenylene diisocyanate, Diisocyanate, tolylene diisocyanate, xylene diisocyanate, and the like.

The alicyclic diisocyanate, for example, one or two C _{6 ~ 20} may be a diisocyanate having a cycloalkyl group, in particular cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexyl methane -4 , 4'-diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexane diisocyanate, and the like.

Preferably, the isocyanate-based curing agent may be an alicyclic diisocyanate, particularly isophorone diisocyanate.

Examples of the epoxy resin include bisphenol-type epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, tetrabromobisphenol A epoxy resin and the like; A spirocyclic epoxy resin; Naphthalene type epoxy resin; Biphenyl type epoxy resins; Terpene type epoxy resin; Glycidyl ether type epoxy resins such as tris (glycidyloxyphenyl) methane, tetrakis (glycidyloxyphenyl) ethane and the like; Glycidylamine-type epoxy resins such as tetraglycidyldiaminodiphenylmethane; Novolak type epoxy resins such as cresol novolak type epoxy resin, phenol novolak type epoxy resin,? -Naphthol novolak type epoxy resin, brominated phenol novolak type epoxy resin and the like. These epoxy resins may be used singly or in combination of two or more.

Among them, bisphenol A type epoxy resin, cresol novolak type epoxy resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin is preferably used in view of adhesion and heat resistance.

The epoxy resin may have an epoxy equivalent of about 80 to 1,000 g / eq, or about 100 to 300 g / eq. In addition, the epoxy resin may have a number average molecular weight ranging from about 10,000 to about 50,000 g / mol.

In addition, the magnetic sheet 100 may include a corrosion inhibitor. Examples of the rust inhibitor include an organic rust inhibitor and an inorganic rust inhibitor.

Specific examples of the organic rust inhibitor include amines, urea, mercaptobenzothiazole (MBT), benzotriazole, tolyltriazole, aldehydes, heterocyclic nitrogen compounds, sulfur-containing compounds, acetylenic compounds, ascorbic acid , Succinic acid, tryptamine, caffeine and the like.

More specifically, the rust inhibitor may be selected from the group consisting of N-benzyl-N, N-bis [(3,5-dimethyl-1H-pyrazol- (Benzimidazol-2-ylmethyl) amine, N- (2-furfuryl) -p-toluidine, N- (5- Chloro-2-furyl) -p-toluidine, N- (5-nitro-2-furyl) (3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, or a mixture of these ≪ / RTI >

The magnetic sheet may contain the magnetic powder in an amount of 50 wt% or more, or 70 wt% or more. For example, the magnetic sheet may contain magnetic powder in an amount of 50 to 95 wt%, 70 to 95 wt%, 70 to 90 wt%, 75 to 90 wt%, 75 to 95 wt%, 80 to 95 wt% By weight to 90% by weight. In this case, the magnetic powder may have the composition of Formula 1.

The magnetic sheet may contain the binder resin in an amount of 5 to 40% by weight, 5 to 20% by weight, 5 to 15% by weight, or 7 to 15% by weight.

The magnetic sheet may further contain, as the binder resin, 6 to 12% by weight of a polyurethane resin, 0.5 to 2% by weight of an isocyanate curing agent, and 0.3 to 1.5% by weight of an epoxy resin, based on the total weight of the magnetic sheet .

The magnetic sheet may contain the antirust agent in an amount of 1 to 10 wt%, 1 to 8 wt%, or 3 to 7 wt%.

According to a specific example, the magnetic sheet comprises a magnetic powder in an amount of 70 to 95% by weight based on the total weight of the magnetic sheet, 6 to 12% by weight of a polyurethane resin as a binder resin, 0.5 to 2% % Of an isocyanate-based curing agent, and 0.3 to 1.5 wt% of an epoxy-based resin. In this case, the magnetic powder preferably has the composition of Formula 1, and the polyurethane resin includes the repeating units represented by the above formulas (2a) and (2b), wherein the isocyanate curing agent is an alicyclic diisocyanate, A type epoxy resin, cresol novolak type epoxy resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin.

The thickness of the magnetic sheet 100 may be about 10-3000 [mu] m. More specifically, the thickness of the magnetic sheet may be about 10 to 500 μm, about 40 to 500 μm, about 40 to 250 μm, about 50 to 250 μm, about 50 to 200 μm, or about 50 to 100 μm.

The magnetic sheet has a magnetic permeability of about 100 to 300 for an alternating current of 3 MHz frequency, a magnetic permeability of about 80 to 270 for an alternating current of 6.78 MHz and a magnetic permeability of about 60 to 250 for an alternating current of 13.56 MHz Lt; / RTI >

Alternatively, the magnetic sheet may have a permeability of about 190 to 250 for an alternating current of 3 MHz frequency, a permeability of about 180 to 230 for an alternating current of 6.78 MHz, and a permeability of about 140 Lt; RTI ID = 0.0 > 180. ≪ / RTI >

In addition, the magnetic sheet may be flexible enough to be applied to various apparatuses. For example, the magnetic sheet may not be cut even after 100, 1,000, or 10,000 bends in an MIT folding test at 90 ° and 35 RPM conditions. Further, the magnetic sheet may have a permeability change of about 10% or less, or about 5% or less after 100 times, 1,000 times, or 10,000 times of bending in an MIT bending test under the conditions of 90 ° and 35 RPM.

Further, the magnetic sheet may have heat resistance capable of withstanding high temperature conditions. For example, the magnetic sheet may have a volume change of less than about 25%, less than 15%, less than 10%, or less than about 5% when heat treated for about 30 minutes at about 150 ° C. Further, the magnetic sheet may have a permeability change of about 25% or less, 15% or less, 10% or less, or about 5% or less when the magnetic sheet is heat-treated at about 150 ° C for about 30 minutes.

The magnetic sheet was heated at a constant speed for 200 seconds from 30 ° C to 240 ° C and then heat-treated at a constant rate from 240 ° C to 130 ° C for 100 seconds. When repeated, the thickness variation and the magnetic permeability change of the magnetic sheet may be about 25% or less, about 15% or less, or about 10% or less. Specifically, when the heat treatment condition is repeated twice, the change in the thickness of the magnetic sheet and the change in the magnetic permeability may be 5% or less, more specifically, 3% or less.

In addition, the magnetic sheet may have chemical resistance that can withstand various environments. When the magnetic sheet is immersed in a solution of about 2N hydrochloric acid for 10 minutes, it may have a mass change of about 10% or less, or about 5% or less. Further, when the magnetic sheet is immersed in a 2N hydrochloric acid solution for 10 minutes, it may have a thickness variation of about 10% or less, or about 5% or less. In addition, the magnetic sheet may have a permeability change of about 10% or less, or about 5% or less when immersed in a 2N hydrochloric acid solution for 10 minutes.

Specifically, when the magnetic sheet is immersed in a 2N hydrochloric acid solution for 30 minutes, it has a thickness change of 5% or less and a permeability change of 5% or less. When the magnetic sheet is immersed in a 2N sodium hydroxide solution for 30 minutes, %. ≪ / RTI >

More specifically, the magnetic sheet has a thickness variation of 3% or less and a permeability change of 3% or less when immersed in a 2N hydrochloric acid solution for 30 minutes and has a thickness variation of 3% or less when immersed in 2N sodium hydroxide solution for 30 minutes and And may have a permeability change of 3% or less.

In addition, the magnetic sheet may have corrosion resistance that can withstand various corrosive environments. For example, a magnetic sheet may have a rating number of 9.8 or higher in a salt spray test according to KS D 9502. The rating number method is an evaluation method that indicates the degree of corrosion by the ratio of corrosion area to effective area, and is divided into values of 0 to 10.

Further, the magnetic sheet may have a mass change of about 10% or less, or about 5% or less when immersed in a 2N NaCl solution for 10 minutes. In addition, the magnetic sheet may have a permeability change of about 10% or less, or about 5% or less when immersed in a 2N NaCl solution for 10 minutes.

When the magnetic sheet is treated for 72 hours under conditions of high temperature and high humidity of 85 캜 and 85% RH, the thickness and permeability change of the magnetic sheet may all be 10% or less, specifically 5% or less, more specifically 2% or less .

Further, the magnetic sheet may have a high tensile strength.

The magnetic sheet according to the embodiment can be produced by a method including mixing magnetic powder and binder resin, and forming and drying in a sheet form. At this time, the magnetic powder and the binder resin may be used in the kind and content as exemplified above.

Specifically, the magnetic sheet comprises: (i) dispersing a magnetic powder in a binder resin and a solvent to prepare a slurry; And (ii) shaping the sheet using the slurry and then drying the sheet.

According to one embodiment, the method for producing the magnetic sheet includes the steps of (1) mixing a polyurethane resin, an isocyanate curing agent, and an epoxy resin to prepare a binder resin; (2) mixing a magnetic powder and an organic solvent in the binder resin to prepare a slurry; And (3) shaping the slurry into a sheet and drying the magnetic sheet, wherein the magnetic sheet comprises, as the binder resin, from 6 wt% to 12 wt%, based on the total weight of the magnetic sheet, Polyurethane-based resin; 0.5% to 2% by weight of an isocyanate-based curing agent; And 0.3% by weight to 1.5% by weight of an epoxy resin.

As a specific example, a magnetic powder is first added to a solvent together with a polyurethane resin, an epoxy resin and an isocyanate curing agent and dispersed by a dispersing machine (planetary mixer, homo mixer, no-bead mill, etc.) ≪ / RTI > Thereafter, the slurry is coated on a carrier film by a comma coater or the like to form a dry magnetic sheet. The dried magnetic sheet may be manufactured from a polymer magnetic sheet (PMS) by adjusting the speed and temperature according to the thickness to be formed, removing the solvent through a drier, and winding the molded sheet.

3, when the manufacturing process of the dried magnetic sheet 101 is performed by a roll-to-roll process, a slurry containing a magnetic powder and a binder resin is coated on the carrier film 400 by a coater 500 And then dried to prepare a dried magnetic sheet 101. [ At this time, the dried magnetic sheet 101 may include an unhardened or semi-hardened binder resin 121.

Thus, the dried magnetic sheet thus produced may be a magnetic sheet in which curing of the binder resin is not completed.

The conductive magnetic composite sheet according to one embodiment includes a magnetic sheet including a magnetic powder and a thermosetting binder resin; And a first conductive foil directly bonded to one surface of the magnetic sheet.

According to another embodiment, the conductive magnetic composite sheet further includes a second conductive foil directly bonded to the other surface of the magnetic sheet.

2 is a cross-sectional view of the conductive magnetic composite sheet according to the embodiment.

Referring to FIG. 2, the conductive composite sheet according to the embodiment includes a magnetic sheet 100, a first conductive foil 210, and a second conductive foil 220.

Thus, the conductive magnetic composite sheet is a composite sheet in which a conductive foil and a magnetic sheet are laminated. For example, the conductive magnetic composite sheet may be a copper-clad laminated magnetic composite sheet.

The magnetic sheet 100 included in the conductive magnetic composite sheet may have substantially the same structure and composition as the magnetic sheet according to the embodiment described above, and may be manufactured by substantially the same method.

The magnetic sheet 100 has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a magnetic permeability of 60 to 250 for an alternating current of 13.56 MHz Lt; / RTI >

According to a specific example, the magnetic sheet comprises a magnetic powder in an amount of 70 to 95% by weight based on the total weight of the magnetic sheet, 6 to 12% by weight of a polyurethane resin as a binder resin, 0.5 to 2% % Of an isocyanate-based curing agent, and 0.3 to 1.5 wt% of an epoxy-based resin. In this case, the magnetic powder preferably has the composition of Formula 1, and the polyurethane resin includes the repeating units represented by the above formulas (2a) and (2b), wherein the isocyanate curing agent is an alicyclic diisocyanate, A type epoxy resin, cresol novolak type epoxy resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin.

The conductive foil is disposed on at least one surface of the magnetic sheet. That is, the conductive foil is disposed on one surface and / or the other surface of the magnetic sheet. As shown in FIG. 2, the first and second conductive foils 210 and 220 are directly bonded to the magnetic sheet 100 without a separate adhesive layer. Accordingly, the first and second conductive foils 210 and 220 can directly contact the surface of the magnetic sheet 100. At this time, the first and second conductive foils 210 and 220 may be directly bonded to the binder resin 120 of the magnetic sheet 100. Specifically, the first and second conductive foils 210 and 220 may be directly bonded to the thermosetting resin constituting the binder resin 120.

The conductive foil may comprise a conductive material. For example, the conductive foil may comprise a conductive metal. That is, the conductive foil may be a metal layer. For example, the conductive foil may comprise one or more metals selected from the group consisting of copper, nickel, gold, silver, zinc and tin. Specifically, the conductive foil may be a metal foil. More specifically, the conductive foil may be a copper foil (copper foil).

The thickness of the conductive foil may be about 6 to 200 microns, and more specifically about 10 to 150 microns, about 10 to 100 microns, or about 20 to 50 microns.

As described above, the conductive foil is bonded by the curing of the thermosetting resin constituting the magnetic sheet, and even if the heat treatment process is performed at a high temperature such as reflow or soldering process for application to the product, .

Preferably, the peel strength between the conductive foil and the magnetic sheet may be 0.6 kgf / cm or more, for example, in the range of 0.6 to 20 kgf / cm, in the range of 0.6 to 10 kgf / cm, in the range of 0.6 to 5 kgf / cm, or in the range of 0.6 to 3 kgf / cm.

Also, the conductive magnetic composite sheet is manufactured by raising the temperature from 30 ° C. to 240 ° C. at a constant rate for 200 seconds, and then repeating the heat treatment twice at a constant rate from 240 ° C. to 130 ° C. for 100 seconds , A peel strength of 0.6 kgf / cm or more between the magnetic sheet and the first conductive foil, for example, a range of 0.6 to 20 kgf / cm, a range of 0.6 to 10 kgf / cm, a range of 0.6 to 5 kgf / cm, or a peel strength in the range of 0.6 to 3 kgf / cm.

Further, when the heat treatment is repeated twice under the above conditions, the rate of change (lowering rate) of the peel strength between the conductive foil and the magnetic sheet may be 20% or less, 15% or less, or 10% or less.

Accordingly, even when the conductive magnetic composite sheet according to the embodiment is subjected to a soldering process such as a reflow process, there is almost no change in physical properties such as magnetic permeability and thickness, and peeling or the like between the magnetic sheet and the conductive foil It does not cause defects.

A method of manufacturing a conductive composite sheet according to an embodiment includes the steps of: preparing a magnetic sheet including magnetic powder and a thermosetting binder resin; Laminating the magnetic sheet and the first conductive foil; And curing the binder resin by applying heat and pressure to the resulting laminate, and bonding the first conductive foil and the magnetic sheet with the binder resin cured.

A method of manufacturing a conductive composite sheet according to another embodiment includes the steps of: preparing a magnetic sheet including a magnetic powder and a thermosetting binder resin; Stacking the first conductive foil, the magnetic sheet and the second conductive foil in order; And curing the binder resin by applying heat and pressure to the obtained laminate, and bonding the first conductive foil, the magnetic sheet and the second conductive foil while the binder resin is cured.

First, the magnetic powder and the binder resin are mixed and formed into a sheet and dried to prepare a dried magnetic sheet.

At this time, the composition of each raw material component and the mixing ratio of each ingredient may be substantially the same as described in the magnetic sheet according to the previous embodiment.

Specifically, the binder resin may include a polyurethane resin, an isocyanate curing agent, and an epoxy resin.

Also, the magnetic sheet may include a magnetic powder in an amount of 70 to 95% by weight based on the total weight of the magnetic sheet, a thermosetting binder resin containing 6 to 12% by weight of a polyurethane resin; 0.5 to 2% by weight of an isocyanate-based curing agent; And 0.3 to 1.5% by weight of an epoxy resin.

As a specific example, the polyurethane resin includes the repeating units represented by the above formulas (2a) and (2b), and the isocyanate-based curing agent is an alicyclic diisocyanate, and the epoxy-based resin is a bisphenol A- Resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin.

The magnetic sheet has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a magnetic permeability of 60 to 250 for an alternating current of 13.56 MHz Permeability.

Thereafter, the first conductive foil is laminated on one surface of the dried magnetic sheet.

Further, the second conductive foil may be further laminated on the other surface of the dried magnetic sheet.

The first conductive foil and the second conductive foil may be a metal foil, more specifically a copper foil (copper foil).

Thereafter, the magnetic sheet and the conductive foil can be bonded while heat and pressure are applied to the obtained laminate, and the uncured or semi-cured binder resin contained in the magnetic sheet is cured.

4, the magnetic sheet 100 having the binder resin cured by heat and pressure is formed, and the first and second conductive foils 210 and 220 are separated from the magnetic sheet 100 ). ≪ / RTI > Since the first and second conductive foils 210 and 220 are bonded to the magnetic sheet 100 by thermal curing, the bonding force between the magnetic sheet and the conductive foil can be excellent. Particularly, since the magnetic sheet and the conductive foil are bonded while the binder resin is cured at the same time as the pressing, the bonding force can be further improved. Accordingly, the magnetic sheet and the conductive foil can be easily bonded without using a separate adhesive layer.

At this time, heat and pressure may be applied to the laminate at a temperature of 100 to 300 DEG C and a pressure of 1 to 100 MPa. Alternatively, heat and pressure may be applied to the laminate at a temperature of 150 to 200 DEG C and a pressure of 5 to 30 MPa. In addition, the process of applying heat and pressure to the magnetic sheet and the conductive foil may be performed for about 0.1 to 5 hours.

Specifically, the heat and pressure applying process may be performed by a roll-to-roll process or a batch process.

As shown in FIG. 5, the step of applying heat and pressure may proceed to a roll-to-roll process. In the roll-to-roll process, the first and second conductive foils 210 and 220 are laminated on one side or both sides of the dried magnetic sheet 101 on which the curing of the binder resin is not completed, and the roll 600 is passed. At this time, the roll itself is heated, and the roll can simultaneously apply heat and pressure to the laminate. That is, the magnetic sheet and the conductive foil are continuously bonded by the roll. As a result, the hardened magnetic sheet 100 is formed, and the first and second conductive foils 210 and 220 can be bonded to the magnetic sheet 100.

In the roll-to-roll process, the temperature of the roll may be about 100 to 300 ° C. Also, the pressure of the roll may be about 1 to 100 MPa. The roll used in the roll-to-roll process may be about 1 to 20 pairs. The moving speed of the laminate may be about 0.1 to 10 m / min.

According to a specific example, the step of laminating and applying heat and pressure is performed by a roll-to-roll process, wherein the roll-to-roll process is performed at a roll temperature of 150-200 ° C, MPa and a speed of 1 to 5 m / min.

As shown in Figure 6, the process of applying heat and pressure may proceed to a batch process. Specifically, the dried magnetic sheet and the conductive foil are laminated, and the laminate thus formed is laminated again to several stages. Thereafter, the magnetic sheet and the conductive foil laminated in several stages are subjected to heat treatment under pressure. As a result, the hardened magnetic sheet 100 is formed, and the laminated bodies 10 in which the first and second conductive foils 210 and 220 are bonded to the magnetic sheet 100 are obtained .

In the arranging step, the heat treatment temperature may be about 100 to 300 ° C. In addition, the pressure applied to the multi-layer stacked body may be about 1 to 100 MPa. In addition, the time for applying heat and pressure may be about 0.1 to 5 hours.

An antenna element according to an embodiment includes a magnetic sheet including a magnetic powder and a thermosetting binder resin; And a first antenna pattern directly bonded to one surface of the magnetic sheet.

An antenna element according to another embodiment includes a magnetic sheet including a magnetic powder and a thermosetting binder resin; A first antenna pattern directly bonded to one surface of the magnetic sheet; And a second antenna pattern directly bonded to the other surface of the magnetic sheet.

In addition, the antenna element may further include a via through the magnetic sheet.

Hereinafter, the antenna element will be described specifically for each constituent element.

The magnetic sheet included in the antenna element may have substantially the same configuration and composition as the magnetic sheet according to the embodiment described above, and may also be manufactured by substantially the same method.

The magnetic sheet has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz Lt; / RTI >

According to a specific example, the magnetic sheet comprises a magnetic powder in an amount of 70 to 95% by weight based on the total weight of the magnetic sheet, 6 to 12% by weight of a polyurethane resin as a binder resin, 0.5 to 2% % Of an isocyanate-based curing agent, and 0.3 to 1.5 wt% of an epoxy-based resin. In this case, the magnetic powder preferably has the composition of Formula 1, and the polyurethane resin includes the repeating units represented by the above formulas (2a) and (2b), wherein the isocyanate curing agent is an alicyclic diisocyanate, A type epoxy resin, cresol novolak type epoxy resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin.

The antenna pattern is disposed on one or both surfaces of the magnetic sheet. At this time, the antenna pattern is directly bonded to the magnetic sheet. Accordingly, the antenna pattern can directly contact one surface or both surfaces of the magnetic sheet.

The antenna pattern may include a conductive material. For example, the antenna pattern may comprise a conductive metal. Specifically, the antenna pattern may include at least one metal selected from the group consisting of copper, nickel, gold, silver, zinc, and tin.

The pattern pattern of the antenna pattern according to the embodiment is not particularly limited. For example, a pattern can be formed to have a variety of functions including an NFC antenna, a WPC antenna, and an MST antenna. . In addition, the antenna pattern may be a printed circuit pattern. The antenna pattern may have a coil shape, a spiral shape, or the like.

The antenna element may further include a via through the magnetic sheet. The vias contact all of the antenna patterns disposed on both sides of the magnetic sheet and electrically connect them. The vias may comprise a conductive material. For example, the vias may comprise one or more metals selected from the group consisting of copper, nickel, gold, silver, zinc and tin.

Further, the magnetic sheet may include via holes penetrating up and down. The via-hole may have a diameter in the range of, for example, 100 to 300 占 퐉, or 120 to 170 占 퐉.

At this time, the first via-hole may be formed by plated the inner wall, filled with a conductive material, or inserted with a solder, a conductive rod or the like. As an example, the magnetic sheet includes a first via hole penetrating up and down, wherein the inner wall of the first via hole is plated to form the first via.

A method of manufacturing an antenna element according to an embodiment includes the steps of: preparing a magnetic sheet including a magnetic powder and a thermosetting binder resin; Laminating the magnetic sheet and the first conductive foil; Curing the binder resin by applying heat and pressure to the resulting laminate, and bonding the first conductive foil and the magnetic sheet with the binder resin cured; And etching the first conductive foil to form a first antenna pattern.

A method of manufacturing an antenna element according to another embodiment includes the steps of: preparing a magnetic sheet including a magnetic powder and a thermosetting binder resin; Stacking the first conductive foil, the magnetic sheet and the second conductive foil in order; Curing the binder resin by applying heat and pressure to the resulting laminate, and bonding the first conductive foil, the magnetic sheet and the second conductive foil while the binder resin is cured; And etching the first conductive foil and the second conductive foil to form a first antenna pattern and a second antenna pattern, respectively.

The magnetic sheet may have substantially the same constitution and physical properties as the magnetic sheet according to the embodiment described above.

As a specific example, the magnetic sheet includes a magnetic powder in an amount of 70 to 95% by weight based on the total weight of the magnetic sheet, 6 to 12% by weight of a polyurethane resin as a binder resin, 0.5 to 2% By weight of an isocyanate-based curing agent and 0.3 to 1.5% by weight of an epoxy-based resin. In this case, the magnetic powder preferably has the composition of Formula 1, and the polyurethane resin includes the repeating units represented by the above formulas (2a) and (2b), wherein the isocyanate curing agent is an alicyclic diisocyanate, A type epoxy resin, cresol novolak type epoxy resin, or tetrakis (glycidyloxyphenyl) ethane type epoxy resin.

Further, the magnetic sheet can be manufactured under substantially the same conditions and by the same method as the method for producing a magnetic sheet according to the above-described embodiment.

Specifically, the magnetic sheet comprises: (a) mixing a polyurethane resin, an isocyanate curing agent, and an epoxy resin to prepare a binder resin; (b) mixing a magnetic powder and an organic solvent in the binder resin to prepare a slurry; And (c) shaping the slurry into a sheet form and drying the slurry.

The conductive magnetic composite sheet is produced through the step of applying heat and pressure, and specific process conditions and methods are as exemplified in the method for producing the conductive magnetic composite sheet.

In the etching step, a mask pattern is formed on the conductive foil using a photoresist, and the conductive foil is patterned through the mask pattern. The etching may be performed using a conventional etching solution such as an aqueous acid solution. At this time, there may be little change in the thickness or permeability of the magnetic sheet due to the excellent chemical resistance of the magnetic sheet.

The method of manufacturing the antenna element may further include a step of forming a via through the magnetic sheet between the step of applying heat and pressure and the step of etching.

12A to 12C show an example of a method of manufacturing an antenna element having a via.

First, as shown in Fig. 12A, a plurality of via-holes 260 are formed in the conductive magnetic composite sheet. The via holes 260 penetrate the magnetic sheet 100 and the first and second conductive foils 210 and 220. The via-hole may have a diameter in the range of, for example, 100 to 300 占 퐉, or 120 to 170 占 퐉.

Thereafter, as shown in FIG. 12B, the vias 250 can be formed by forming a plating layer on the inner surfaces of the via-holes 260. When the vias are formed by the plating process, vias formed in a large area can be formed at a time. That is, when the vias are formed of a plating layer, they can be easily and efficiently formed. Alternatively, conductive powder may be filled in the via-holes and then sintered to form vias. Alternatively, the vias may be formed by inserting solder or a conductive bar into the via-holes.

Thereafter, a mask pattern is formed by a process such as photoresist covering the first and second conductive foils 210 and 220, and the first conductive foil 210 is patterned by the mask pattern as shown in FIG. Selectively etched and an antenna pattern 230 is formed. Preferably, since the magnetic sheet has improved chemical resistance, the thickness of the magnetic sheet in the etching process may be substantially unchanged.

Further, the binder resin of the magnetic sheet adheres to the antenna pattern. That is, the binder resin of the magnetic sheet is bonded to the antenna pattern by a heat curing process. Accordingly, in the etching process, the etching liquid does not penetrate between the magnetic sheet and the antenna pattern. As a result, the antenna pattern can be bonded to the magnetic sheet with an improved bonding force.

The antenna element according to the embodiment can reduce the thickness and simplify the manufacturing process by directly forming the conductive foil or the antenna pattern layer on the magnetic sheet without an insulating substrate such as polyimide, WPC and MST. In addition, flexibility can be improved by using a polymer-type magnetic sheet, and manufacturing can be performed by a roll-to-roll process, thereby improving the processability.

In particular, the magnetic sheet can harden the binder resin by heat and can more firmly hold the magnetic powder, so that the magnetic sheet can be hardened even when various environmental changes such as etching treatment for patterning or reflow or soldering for application to a product, There may be little change in thickness.

The antenna element according to the embodiment may have various configurations through the shape of the antenna pattern, the connection of vias and terminals, or the addition of wires. Hereinafter, specific embodiments of the antenna element will be exemplarily described.

According to one embodiment, referring to Figure 7, the antenna element comprises a magnetic sheet 100; A first antenna pattern 230 disposed on one side of the magnetic sheet 100; A wiring pattern 240 disposed on the other surface of the magnetic sheet 100; And a first via 251 penetrating through the magnetic sheet 100. The first via 251 is electrically connected to one end of the first antenna pattern 230 and one end of the wiring pattern 240, Lt; / RTI >

The antenna element according to the embodiment may further include a first terminal pattern 271 and a second terminal pattern 272 on one side or the other side of the magnetic sheet 100, And a second via 252 penetrating through the second via 252. Designing various antenna elements is possible according to their arrangement position and connection configuration.

FIGS. 8 to 10 show plan views of antenna elements according to various exemplary embodiments (the black pattern is a front pattern, the hatched pattern is a back pattern, and the circles are vias).

Hereinafter, more specific examples of the antenna element of the specific embodiment will be described with reference to the drawings.

8, the antenna element according to the embodiment includes a first terminal pattern 271 disposed on one side of the magnetic sheet 100; And a second via 252 penetrating through the magnetic sheet 100. The second via 252 is electrically connected to the first terminal pattern 271 and the other end of the wiring pattern 240, Can be connected. At this time, the antenna element further includes a second terminal pattern 272 disposed on one side of the magnetic sheet 100, and the other end of the first antenna pattern 230 is connected to the second terminal pattern 272, respectively. At this time, the first terminal pattern 271 and the second terminal pattern 272 may be disposed adjacent to each other.

9, the antenna element according to the embodiment further includes a first terminal pattern 271 disposed on the other surface of the magnetic sheet 100, and the first terminal pattern 271 May be connected to the other end of the wiring pattern 240. At this time, the antenna element includes a second terminal pattern 272 disposed on the other surface of the magnetic sheet 100; And a second via 252 penetrating through the magnetic sheet 100. The second via 252 is electrically connected to the second terminal pattern 272 and the other end of the first antenna pattern 230, Lt; / RTI > At this time, the first terminal pattern 271 and the second terminal pattern 272 may be disposed adjacent to each other.

10, the antenna element according to the embodiment further includes a first terminal pattern 271 disposed on the other surface of the magnetic sheet 100, and the first terminal pattern 271 May be connected to the other end of the wiring pattern 240. The antenna element may further include a second terminal pattern 272 disposed on one side of the magnetic sheet 100 and the second terminal pattern 272 may be formed on the other side of the first antenna pattern 230, Can be connected to the end.

The first antenna pattern and the wiring pattern are made of a conductive material, and the first antenna pattern is directly bonded to one surface of the magnetic sheet, Can be directly bonded to the other surface.

In the antenna element according to the embodiment, Referring to FIG. 13, the electromagnetic signal 50 can be generated due to the current flowing through the first antenna pattern. The electromagnetic signal 50 enables signal transmission / reception between the antenna element 20 and the external terminal 40.

In the antenna element according to the embodiment, the first antenna pattern and the wiring pattern are disposed on different surfaces of the magnetic sheet, and these patterns are connected to each other through the vias passing through the magnetic sheet. Thus, Since the same additional process is not required, the efficiency of the process can be increased. In addition, the antenna element according to the embodiment can prevent the thickness increase due to the covering of the wiring for insulation and the like, so that the thin film characteristics of the antenna element can be further improved.

The antenna element may include conductive line patterns as antenna patterns.

According to another embodiment, the antenna element comprises a magnetic sheet; A plurality of first conductive line patterns spaced apart from each other on one surface of the magnetic sheet; A plurality of second conductive line patterns spaced apart from each other on a second surface of the magnetic sheet; And a plurality of vias disposed through the magnetic sheet, wherein the extending directions of the first conductive line patterns and the second conductive line patterns are the same, 2 conductive line patterns.

Specifically, the vias alternately connect the first conductive line patterns and the second conductive line patterns spaced apart from each other, so that one end and the other end of the first conductive line patterns are adjacent to each other And one end of the second conductive line patterns and the other end of the second conductive line patterns may be respectively connected to two first conductive line patterns adjacent to each other.

In addition, when the magnetic sheet is divided into a core region and a peripheral region around the core region, the first conductive line patterns and the second conductive line patterns extend across the core region, and both ends are disposed in the peripheral region The vias may be disposed in the peripheral region to connect the ends of the first conductive line patterns and the second conductive line patterns.

At this time, the first conductive line patterns, the second conductive line patterns, and the vias may be connected to each other to form a coil that winds the core region.

11A and 11B, the antenna element according to another embodiment of the present invention includes a magnetic sheet 100, a plurality of first conductive line patterns 231, a plurality of second conductive line patterns 232, (Not shown).

The magnetic sheet may be divided into a core region CR and a peripheral region OR adjacent to the core region.

The core region is disposed at a central portion of the magnetic sheet. The core region may have a shape extending in one direction.

The peripheral region is disposed around the core region. The peripheral region may have a shape extending in the same direction as the core region. The peripheral region may be disposed on both sides of the core region.

The first conductive line patterns are disposed on the magnetic sheet. More specifically, the first conductive line patterns are bonded to one surface of the magnetic sheet.

The first conductive line patterns may extend in a direction intersecting a direction in which the core region extends. More specifically, the first conductive line patterns may extend across the core region. The first conductive line patterns may extend from a peripheral region disposed on one side of the core region to a peripheral region disposed on the other side.

The first conductive line patterns may extend in parallel with each other. In addition, the first conductive line patterns may be spaced apart from each other.

And the second conductive line patterns are disposed on the other side of the magnetic sheet. More specifically, the second conductive line patterns are bonded to the other surface of the magnetic sheet.

The second conductive line patterns may extend in a direction intersecting the direction in which the core region extends. More specifically, the second conductive line patterns may extend across the core region. The second conductive line patterns may extend from a peripheral region disposed on one side of the core region to a peripheral region disposed on the other side.

The second conductive line patterns may extend in parallel with each other. In addition, the second conductive line patterns may be spaced apart from each other.

The vias penetrate the magnetic sheet. The vias connect the first conductive line patterns and the second conductive line patterns. More specifically, the vias may be connected to one end of the first conductive line pattern and one end of the second conductive line pattern.

The vias may alternately connect the first conductive line patterns and the second conductive line patterns. For example, a first conductive line pattern, a via, a second conductive line pattern, a via, a first conductive line pattern, a via, a second conductive line pattern, and a via may be sequentially connected.

The first conductive line pattern, the second conductive line pattern, and the vias may be connected to each other to form a coil wound around the core region. Specifically, the first conductive line pattern, the second conductive line pattern, and the via may be connected to each other to form a coil spirally wound around the core region.

Accordingly, when alternating current flows through the first conductive line pattern, the second conductive line pattern, and the via, electromagnetic signals can be formed through both ends of the core region.

As a preferred example, the magnetic sheet is formed thin, and the electromagnetic signal can be formed through the end of the core region at a high magnetic flux density. Accordingly, the antenna element according to the embodiment can have an improved reception sensitivity, and can easily transmit and receive electromagnetic signals even in a narrow gap.

FIG. 14 illustrates a portion of a portable terminal to which an antenna element according to another embodiment of the present invention is applied. Referring to Fig. 14, the antenna element 20 is disposed in the case 30. The case 30 includes an electromagnetic wave transmitting region 32 and an electromagnetic wave non-transmitting region 31. The electromagnetic wave non-transmissive region may include a material that is shielded from electromagnetic waves such as metal. The electromagnetic wave transmitting region may include a material through which electromagnetic waves such as glass or plastic can be easily transmitted. The antenna element according to the embodiment can effectively exchange the electromagnetic signal 50 with the external terminal 40 even if the transmission region is narrowly formed.

On the other hand, a conventional antenna element is manufactured by forming an antenna pattern on an insulating base layer such as polyimide and padding a magnetic sheet so that even if a conductive line pattern is formed on both sides of the base layer and alternately connected via vias, The electromagnetic signal is clogged by the magnetic sheet attached on one side. On the other hand, the antenna element according to the embodiment forms a conductive line pattern formed on both sides by using a magnetic sheet as a base layer and forms a coil by alternately connecting through a via, so that the flow of electromagnetic signals is not blocked, Characteristics can have improved communication sensitivity.

Hereinafter, more specific embodiments will be described by way of example.

The materials used in the following examples are as follows:

- Sandst powder: C1F-02A, Crystallite Technology

- Polyurethane resin: UD1357, Daiichi Seika Kogyo Co., Ltd.

- Isocyanate-based curing agent: isophorone diisocyanate, Sigma-Aldrich

- Epoxy resin: bisphenol A epoxy resin (epoxy equivalent = 189 g / eq), Epikote ^TM 828, Japan Epoxy Resin

Example 1: Fabrication of antenna element

Step 1) Preparation of magnetic powder slurry

, 42.8 parts by weight of sandstock powder, 15.4 parts by weight of a polyurethane-based resin dispersion (25% by weight of a polyurethane resin and 75% by weight of 2-butanone) and 1.0 part by weight of an isocyanate curing agent dispersion (62% by weight of an isocyanate- (Epoxy resin 70 wt.%, N-butyl acetate 3 wt.%, 2-butanone 15 wt.%, Toluene 13 wt.%), And 40.5 parts by weight of toluene was mixed in a planetary mixer at a speed of about 40-50 rpm for about 2 hours to prepare a magnetic powder slurry.

Step 2) Production of magnetic sheet

The previously prepared magnetic powder slurry was coated on a carrier film with a comma coater and dried at a temperature of about 110 캜 to form a dried magnetic sheet. The dried magnetic sheet was compression-cured by a hot press process at a temperature of about 170 캜 and a pressure of about 9 MPa for about 30 minutes to obtain a final magnetic sheet.

Step 3) Production of the copper-clad laminated magnetic composite sheet

A copper foil of about 37 mu m was disposed on both sides of the dried magnetic sheet to form a laminate. Thereafter, the laminate was compressed by a heat press process at a temperature of about 170 캜 and a pressure of about 9 MPa for about 60 minutes to cure the binder resin in the magnetic sheet, thereby producing a copper-clad laminated magnetic composite sheet.

Step 4) Manufacture of antenna element

By using a drill, a plurality of via-holes having a diameter of about 0.15 mm were formed in the above-mentioned copper-clad laminated magnetic composite sheet. Thereafter, a copper plating layer was formed in the via-holes through a copper plating process. The plating layer served as vias connecting the copper foils on the upper and lower sides to each other. Thereafter, a mask pattern was formed on the upper and lower surfaces of the above-described copper-clad laminated magnetic composite sheet, and a part of the copper foil was etched through an etching process. Accordingly, the upper patterns and the lower patterns were formed.

The magnetic sheet prepared in the step (2) of Example 1, the copper-clad laminated magnetic composite sheet prepared in the step (3) and the antenna element produced in the step (4) were tested according to the following procedure.

Test Example 1. Measurement of permeability

Through the impedance analysis equipment, the permeability and investment loss of the magnetic sheet were measured. The results are summarized in Table 1 below.

@ 3 MHz @ 6.78 MHz @ 13.56 MHz Investment ratio Investment loss Investment ratio Investment loss Investment ratio Investment loss 215 17.5 200 50.1 160 63

As shown in Table 1, the magnetic sheet according to the embodiment had excellent permeability in all three bands.

Test Example 2. Heat Resistance Measurement - Reflow Test

The magnetic sheet, the copper-clad laminated magnetic composite sheet and the antenna element were placed in an oven, the temperature was raised from 30 ° C to 240 ° C at a constant speed for 200 seconds, the temperature was lowered at a constant rate from 240 ° C to 130 ° C for 100 seconds The reflow test was performed twice under the heat treatment condition (see FIG. 15). Thereafter, the thickness variation, the magnetic permeability variation and the bonding force variation of the magnetic sheet, the copper-clad laminated magnetic composite sheet and the antenna element were measured.

As a result, no blister was observed on the surface of the magnetic sheet even after the second reflow test. Further, after the second reflow test, both the thickness of the magnetic sheet and the permeability change were measured to be less than 5%. Further, the peel strength of the magnetic sheet with copper after the second reflow test was measured to be not less than 0.6 kgf / cm.

Test Example 3. Heat Resistance Measurement - Pb Floating Test

After the magnetic sheet and the copper-clad laminated magnetic composite sheet were placed in a fused bath and allowed to stand for 40 seconds, the surface was observed. As a result, no blister was observed on the surfaces of the magnetic sheet and the copper-clad laminated magnetic composite sheet.

Test Example 4. Measurement of Chemical Resistance

After immersing the magnetic sheet in the aqueous 2N HCl solution for about 30 minutes, the mass change, the thickness change and the magnetic permeability change of the magnetic sheet were measured. Further, after the magnetic sheet was immersed in the aqueous 2N NaOH solution for about 30 minutes, the mass change, the thickness change and the magnetic permeability change of the magnetic sheet were measured. As a result, no precipitation of magnetic powder occurred in the lower part of the solution, and the mass change, the mass change of the magnetic sheet, the thickness change and the permeability change were both measured to be less than 5%.

Test Example 5. Measurement of rust-inhibiting properties

KS D9502, a magnetic sheet was sprayed with NaCl neutral brine at a concentration of 5% at an average of 1 to 2 mL per hour for 72 hours at 35 ° C, and then rust formation was observed. The ration number was measured by the area method (rating number method) to be 9.8 or more. (Rating number method is an evaluation method indicating the degree of corrosion by the ratio of corrosion area to effective area. .

Test Example 6 Peel strength measurement

Using a universal testing machine (UTM), the peel strength between the magnetic sheet and the copper foil of the copper-clad laminated magnetic composite sheet was measured. As a result, the peel strength was measured to be 0.6 kgf / cm or more.

Test Example 7. Measurement of joint strength - Crosscut test

The bonding force between the magnetic sheet and the copper foil of the copper-clad laminated magnetic composite sheet was measured by the cross-cut test (ASTM D3369). Cross cut test results were measured as 0/100 to 5/100.

Test Example 8. Measurement of high temperature and high humidity characteristics

After the magnetic sheet was allowed to stand in a constant temperature and humidity oven at 85 ° C / 85% RH for 72 hours, the change in the thickness of the magnetic sheet and the change in the magnetic permeability were measured. As a result, both the change in the thickness of the magnetic sheet and the change in the magnetic permeability were all measured to be 5% or less.

10: laminate,
20: an antenna element according to the embodiment, 30: case,
31: Electromagnetic wave non-transmission area, 32: Electromagnetic wave transmission area,
40: external terminal, 50: electromagnetic signal,
100: magnetic sheet (cured)
101: a dry magnetic sheet (in which curing is not completed)
110: magnetic powder,
120: binder resin (cured)
121: binder resin (not cured)
210: first conductive foil, 220: second conductive foil,
230: first antenna pattern,
231: first conductive line pattern, 232: second conductive line pattern,
240: wiring pattern, 250: via,
251: first via, 252: second via,
260: via hole,
271: first terminal pattern, 272: second terminal pattern,
400: carrier film,
500: Coater, 600: Roll,
CR: core region, OR: peripheral region.

Claims (15)

Preparing a magnetic sheet comprising a magnetic powder and a thermosetting binder resin;
Laminating the magnetic sheet and the first conductive foil; And
And curing the binder resin by applying heat and pressure to the obtained laminate to bond the first conductive foil and the magnetic sheet while the binder resin is cured,
The first conductive foil is directly bonded to the magnetic sheet without an adhesive layer,
When the temperature is raised from 30 ° C to 240 ° C at a constant rate for 200 seconds and then the temperature is lowered at a constant rate from 240 ° C to 130 ° C for 100 seconds, the magnetic sheet and the first The peeling strength between the conductive foils is 0.6 to 20 kgf / cm, and the rate of decrease of the peeling strength is 10% or less when the heat treatment is repeated twice,
The magnetic sheet has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz Wherein the conductive magnetic composite sheet is produced by the method.
The method according to claim 1,
Applying heat and pressure to the laminate at a temperature of 150 to 200 DEG C and a pressure of 5 to 30 MPa.
3. The method of claim 2,
The laminating step and the step of applying heat and pressure are performed by a roll-to-roll process, wherein the roll-to-roll process is performed at a roll temperature of 150 to 200 DEG C, a roll pressure of 5 to 30 MPa, At a speed of 1 to 5 m / min.
The method according to claim 1,
Wherein the binder resin comprises a polyurethane resin, an isocyanate curing agent, and an epoxy resin.
The method according to claim 1,
The magnetic sheet is characterized in that, based on the total weight of the magnetic sheet,
The magnetic powder is contained in an amount of 70 to 95% by weight,
As the thermosetting binder resin, 6 to 12% by weight of a polyurethane resin; 0.5 to 2% by weight of an isocyanate-based curing agent; And 0.3 to 1.5% by weight of an epoxy resin.
The method according to claim 1,
The magnetic sheet
The temperature is raised from 30 ° C. to 240 ° C. at a constant rate for 200 seconds, and then the temperature is lowered at a constant rate from 240 ° C. to 130 ° C. for 100 seconds. When the heat treatment is repeated twice, Having a permeability change of 5% or less,
When it is immersed in a 2N hydrochloric acid solution for 30 minutes, it has a thickness change of 5% or less and a permeability change of 5% or less. When immersed in 2N sodium hydroxide solution for 30 minutes, the thickness change is less than 5% , And a method for producing a conductive magnetic composite sheet.
Preparing a magnetic sheet comprising a magnetic powder and a thermosetting binder resin;
Stacking the first conductive foil, the magnetic sheet and the second conductive foil in order; And
Curing the binder resin by applying heat and pressure to the resulting laminate and bonding the first conductive foil, the magnetic sheet and the second conductive foil while the binder resin is cured. A process for producing
Wherein the first conductive foil and the second conductive foil are directly bonded to the magnetic sheet without an adhesive layer,
When the temperature is raised from 30 ° C to 240 ° C at a constant rate for 200 seconds and then the temperature is lowered at a constant rate from 240 ° C to 130 ° C for 100 seconds, the magnetic sheet and the first The peeling strength between the conductive foil and the second conductive foil is 0.6 to 20 kgf / cm 2, and the rate of decrease of the peeling strength is 10% or less when the heat treatment is repeated twice,
The magnetic sheet has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz Wherein the conductive magnetic composite sheet is produced by the method.
8. The method of claim 7,
The magnetic sheet is characterized in that, based on the total weight of the magnetic sheet,
The magnetic powder is contained in an amount of 70 to 95% by weight,
As the thermosetting binder resin, 6 to 12% by weight of a polyurethane resin; 0.5 to 2% by weight of an isocyanate-based curing agent; And 0.3 to 1.5% by weight of an epoxy resin.
A magnetic sheet comprising a magnetic powder and a thermosetting binder resin; And
And a first conductive foil directly bonded to one surface of the magnetic sheet,
As the conductive magnetic composite sheet,
The first conductive foil is directly bonded to the magnetic sheet without an adhesive layer,
When the temperature is raised from 30 ° C to 240 ° C at a constant rate for 200 seconds and then the temperature is lowered at a constant rate from 240 ° C to 130 ° C for 100 seconds, the magnetic sheet and the first The peeling strength between the conductive foils is 0.6 to 20 kgf / cm, and the rate of decrease of the peeling strength is 10% or less when the heat treatment is repeated twice,
The magnetic sheet has a magnetic permeability of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz A conductive magnetic composite sheet.
10. The method of claim 9,
Wherein the conductive magnetic composite sheet further comprises a second conductive foil directly bonded to the other surface of the magnetic sheet.
10. The method of claim 9,
The magnetic sheet is characterized in that, based on the total weight of the magnetic sheet,
The magnetic powder is contained in an amount of 70 to 95% by weight,
As the thermosetting binder resin, 6 to 12% by weight of a polyurethane resin; 0.5 to 2% by weight of an isocyanate-based curing agent; And 0.3 to 1.5% by weight of an epoxy resin.
10. The method of claim 9,
The magnetic sheet
The temperature is raised from 30 ° C. to 240 ° C. at a constant rate for 200 seconds, and then the temperature is lowered at a constant rate from 240 ° C. to 130 ° C. for 100 seconds. When the heat treatment is repeated twice, Having a permeability change of 5% or less,
When it is immersed in a 2N hydrochloric acid solution for 30 minutes, it has a thickness change of 5% or less and a permeability change of 5% or less. When immersed in a 2N sodium hydroxide solution for 30 minutes, a thickness change of 5% or less and a permeability change of 5% , A conductive magnetic composite sheet.
Preparing a magnetic sheet comprising a magnetic powder and a thermosetting binder resin;
Laminating the magnetic sheet and the first conductive foil;
Curing the binder resin by applying heat and pressure to the resulting laminate, and bonding the first conductive foil and the magnetic sheet with the binder resin cured; And
And etching the first conductive foil to form a first antenna pattern, the method comprising the steps of:
The first conductive foil is directly bonded to the magnetic sheet without an adhesive layer,
When the temperature is raised from 30 ° C to 240 ° C at a constant rate for 200 seconds and then the temperature is lowered at a constant rate from 240 ° C to 130 ° C for 100 seconds, the magnetic sheet and the first The peeling strength between the conductive foils is 0.6 to 20 kgf / cm, and the rate of decrease of the peeling strength is 10% or less when the heat treatment is repeated twice,
The magnetic sheet has a thickness change of 5% or less and a permeability change of 5% or less when immersed in a 2N hydrochloric acid solution for 30 minutes and has a thickness change of 5% or less and a thickness change of 5% or less when immersed in 2N sodium hydroxide solution for 30 minutes Having a magnetic permeability change of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz, Of the antenna element.
A magnetic sheet comprising a magnetic powder and a thermosetting binder resin; And
And a first antenna pattern directly bonded to one surface of the magnetic sheet,
As an antenna element,
The first antenna pattern is formed by directly bonding the first conductive foil to one surface of the magnetic sheet by heat and pressure and then etching. The temperature is raised from 30 ° C to 240 ° C for 200 seconds at a constant rate, And the temperature is lowered at a constant rate for a period of 100 seconds from 130 deg. C to 100 deg. C. The peeling strength between the magnetic sheet and the first conductive foil is 0.6 to 20 kgf / cm, The rate of decrease of the peel strength is not more than 10%
The magnetic sheet has a thickness change of 5% or less and a permeability change of 5% or less when immersed in a 2N hydrochloric acid solution for 30 minutes and has a thickness change of 5% or less and a thickness change of 5% or less when immersed in 2N sodium hydroxide solution for 30 minutes Having a magnetic permeability change of 100 to 300 for an alternating current of 3 MHz frequency and a permeability of 80 to 270 for an alternating current of 6.78 MHz and a permeability of 60 to 250 for an alternating current of 13.56 MHz, .
15. The method of claim 14,
The magnetic sheet is characterized in that, based on the total weight of the magnetic sheet,
The magnetic powder is contained in an amount of 70 to 95% by weight,
As the thermosetting binder resin, 6 to 12% by weight of a polyurethane resin; 0.5 to 2% by weight of an isocyanate-based curing agent; And 0.3 to 1.5% by weight of an epoxy resin.

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