WO2018235952A1 - 電磁波吸収性組成物、電磁波吸収シート - Google Patents
電磁波吸収性組成物、電磁波吸収シート Download PDFInfo
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- WO2018235952A1 WO2018235952A1 PCT/JP2018/023865 JP2018023865W WO2018235952A1 WO 2018235952 A1 WO2018235952 A1 WO 2018235952A1 JP 2018023865 W JP2018023865 W JP 2018023865W WO 2018235952 A1 WO2018235952 A1 WO 2018235952A1
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K9/00—Screening of apparatus or components against electric or magnetic fields
- H05K9/0073—Shielding materials
- H05K9/0081—Electromagnetic shielding materials, e.g. EMI, RFI shielding
- H05K9/0083—Electromagnetic shielding materials, e.g. EMI, RFI shielding comprising electro-conductive non-fibrous particles embedded in an electrically insulating supporting structure, e.g. powder, flakes, whiskers
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L67/00—Compositions of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Compositions of derivatives of such polymers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L75/00—Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
- C08L75/04—Polyurethanes
- C08L75/06—Polyurethanes from polyesters
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
- H01F1/36—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles
- H01F1/37—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites in the form of particles in a bonding agent
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2206—Oxides; Hydroxides of metals of calcium, strontium or barium
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K3/00—Use of inorganic substances as compounding ingredients
- C08K3/18—Oxygen-containing compounds, e.g. metal carbonyls
- C08K3/20—Oxides; Hydroxides
- C08K3/22—Oxides; Hydroxides of metals
- C08K2003/2265—Oxides; Hydroxides of metals of iron
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/01—Magnetic additives
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
- H01F1/342—Oxides
- H01F1/344—Ferrites, e.g. having a cubic spinel structure (X2+O)(Y23+O3), e.g. magnetite Fe3O4
- H01F1/348—Hexaferrites with decreased hardness or anisotropy, i.e. with increased permeability in the microwave (GHz) range, e.g. having a hexagonal crystallographic structure
Definitions
- the present disclosure relates to an electromagnetic wave absorbing composition having a property of absorbing an electromagnetic wave, and in particular, an electromagnetic wave absorbing property that includes magnetic iron oxide powder as an electromagnetic wave absorbing material and can absorb radio waves of high frequencies above the millimeter wave band.
- the present invention relates to a composition and an electromagnetic wave absorbing sheet provided with the electromagnetic wave absorbing composition as an electromagnetic wave absorbing layer.
- an electromagnetic wave absorbing composition that absorbs the radio wave is used.
- the electromagnetic wave absorbing composition is molded into a predetermined shape as an electromagnetic wave absorbing member such as a block-like electromagnetic wave absorber or a sheet-like electromagnetic wave absorbing sheet, and a form of use as an electromagnetic wave absorbing paint applied to a desired place It is also known.
- electromagnetic wave absorbers In response to technology trends that use radio waves of such higher frequencies, electromagnetic wave absorbers, electromagnetic wave absorbing sheets and electromagnetic wave absorbing coatings that absorb unnecessary radio waves can absorb radio waves from the gigahertz band to the terahertz band There is a growing demand for what to do.
- Patent Document 1 Particles that have epsilon iron oxide ( ⁇ -Fe 2 O 3 ) crystals in the magnetic phase that exhibit electromagnetic wave absorption performance in the range of 25 to 100 GHz as electromagnetic wave absorbers that absorb radio waves in high frequency bands above the millimeter wave band
- An electromagnetic wave absorber having a filling structure has been proposed (see Patent Document 1).
- a sheet-like oriented body has been proposed in which fine particles of epsilon iron oxide are kneaded with a binder, and a magnetic field is externally applied during drying and curing of the binder to enhance the magnetic field orientation of epsilon iron oxide particles. (See Patent Document 2).
- an electromagnetic wave absorbing sheet having elasticity an electromagnetic wave absorbing sheet in which carbon nanotubes are dispersed in silicone rubber has been proposed (see Patent Document 3). Also, by using alkali metal silicate salt-based water glass as a binder, an electromagnetic wave absorbing paint is proposed that has heat resistance of 300 degrees or more and can be used in parts that are in a high temperature state such as around engine exhaust ports. (See Patent Document 4).
- an organic metal complex having magnetic spin such as Co (cobalt) or Fe (iron) as a clathrate containing a rare earth ion is used as an electromagnetic wave absorbing fine particle, and an acid value of 8-20, an amine value of 20- 32.
- An ink composition for an electromagnetic wave absorber comprising a polymer-type wetting dispersant and a resin binder (see Patent Document 5), and a water-soluble resin having an amine value of 20 mg KOH / g or more and an acid value of 30 mg KOH / g or more
- a paste composition for an electronic material containing an inorganic oxide such as a black pigment containing an inorganic dispersant has been proposed.
- the electromagnetic wave absorbing material When shielding the leaked electromagnetic wave from the generation source which generates the electromagnetic wave, it is necessary to arrange the electromagnetic wave absorbing material in a housing etc. which covers the target circuit component, but especially when the shape of the arrangement place is not planar shape. It is more convenient to use an electromagnetic wave absorbing sheet with flexibility than using an electromagnetic wave absorber which is a solid body. In the case of covering a large area such as a wall surface or covering the entire mechanical device having a complicated shape, it is useful to use an electromagnetic wave absorbing paint that exhibits electromagnetic wave absorbability by coating.
- the frequency of the radio wave that can be absorbed is in the centimeter wave band, and in the electromagnetic wave absorbing paint described in Patent Document 4, the frequency of the radio wave to be absorbed remains around 10 GHz. ing.
- the paste composition of patent document 5 and patent document 6 does not absorb the electromagnetic waves of the high frequency more than a millimeter-wave zone.
- an electromagnetic wave absorbing composition capable of absorbing electromagnetic waves in the so-called millimeter wave band or more with a frequency of several tens of gigahertz or more, it is applied to an electromagnetic wave absorbing sheet having sufficient flexibility or elasticity, or a desired place.
- the electromagnetic wave absorbing paint that can be done is not realized.
- the present disclosure is an electromagnetic wave absorbing sheet capable of favorably absorbing electromagnetic waves of high frequency in the millimeter wave band and higher, and having sufficient flexibility and elasticity. It is another object of the present invention to obtain an electromagnetic wave absorbing composition which can be used as an electromagnetic wave absorbing paint.
- the electromagnetic wave absorbing composition disclosed in the present application contains a magnetic iron oxide powder having a magnetic resonance frequency, a binder resin, and a dispersant, and the acid value of the dispersant is 8 mg KOH / g to 46 mg KOH / G or less, amine value is 18 mg KOH / g or more and 44 mg KOH / g or less.
- the electromagnetic wave absorbing composition disclosed in the present application uses a magnetic iron oxide powder having a magnetic resonance frequency capable of absorbing high frequencies in the millimeter wave band by magnetic resonance as an electromagnetic wave absorbing material, a resin binder, and an acid value of 8 mg KOH
- the dispersant contains a dispersant of 1 g / g to 46 mg KOH / g and an amine value of 18 mg KOH / g to 44 mg KOH / g.
- a fine magnetic iron oxide powder can be favorably dispersed in the binder, and an electromagnetic wave absorbing sheet having flexibility and elasticity, or an electromagnetic wave absorbing composition which can be used as an electromagnetic wave absorbing paint can be obtained. be able to.
- the electromagnetic wave absorbing composition disclosed in the present application is an electromagnetic wave absorbing composition containing magnetic iron oxide powder having a magnetic resonance frequency, a binder resin, and a dispersing agent, and the acid value of the dispersing agent is 8 mg KOH / g
- the amine number is 18 mg KOH / g or more and 44 mg KOH / g or less.
- the electromagnetic wave absorbing composition disclosed in the present application can disperse the magnetic iron oxide powder having a magnetic resonance frequency, which is an electromagnetic wave absorbing material, in the binder well, and is formed into a sheet shape. In some cases, high flexibility and elasticity can be achieved, and it can be stored as a solution for a long time.
- the glass transition temperature (Tg) of the binder resin is preferably ⁇ 10 ° C. to ⁇ 40 ° C.
- the magnetic iron oxide powder is at least one of epsilon iron oxide and strontium ferrite.
- the magnetic iron oxide powder is at least one of epsilon iron oxide and strontium ferrite.
- an electromagnetic wave absorbing composition that makes use of the high electromagnetic wave absorption performance of epsilon iron oxide and strontium ferrite.
- a part of the Fe site of the epsilon iron oxide is substituted by a trivalent metal atom. In this way, an electromagnetic wave absorbing composition that absorbs radio waves in a desired frequency band can be easily realized.
- seat provided with high flexibility and elasticity is realizable by comprising an electromagnetic wave absorption layer by one of the electromagnetic wave absorptive compositions concerning this application.
- FIG. 1 is a cross-sectional view for explaining the configuration of an electromagnetic wave absorbing sheet formed using the electromagnetic wave absorbing composition according to the present embodiment.
- FIG. 1 the state which apply
- FIG. 1 is a view described to facilitate understanding of the configuration of the electromagnetic wave absorbing sheet according to the present embodiment, and represented in reality with respect to the size and thickness of the members shown in the figure. It is not a thing.
- the electromagnetic wave absorbing sheet 1 exemplified in the present embodiment includes a magnetic iron oxide powder 1a, which is a particulate electromagnetic wave absorbing material having a magnetic resonance frequency, and a resin binder 1b. In addition, it contains a dispersant for well dispersing the magnetic iron oxide powder 1a in the resinous binder 1b. In addition, the dispersing agent is illustrated including in the resin-made binders 1b.
- the powder of epsilon iron oxide is used as the magnetic iron oxide powder 1a, and the epsilon iron oxide causes magnetic resonance to convert the electromagnetic wave into thermal energy and dissipate it by magnetic loss. .
- absorption of electromagnetic waves is possible only with an electromagnetic wave absorption sheet, and it can be used as what is called a transmission type electromagnetic wave absorption sheet which does not equip a back surface with a reflection layer.
- Electromagnetic wave absorbing material In the electromagnetic wave absorbing sheet according to the present embodiment, magnetic powder of epsilon iron oxide is used as magnetic iron oxide powder having a magnetic resonance frequency.
- Epsilon iron oxide is a ferric oxide (Fe 2 O 3 ) between the alpha phase ( ⁇ -Fe 2 O 3 ) and the gamma phase ( ⁇ -Fe 2 O 3 ) It is a magnetic material that is a phase that appears and can be obtained in a single phase state by a nanoparticulate synthesis method combining reverse micelle method and sol-gel method.
- Epsilon-iron oxide is a fine particle of several nm to several tens of nm, but has maximum coercivity as a metal oxide of about 20 kOe at normal temperature, and furthermore, dozens of natural magnetic resonances due to the precession gyromagnetic effect. Since it occurs in the so-called millimeter wave band of gigahertz or more, it has a high effect of absorbing high frequency electromagnetic waves of 30 to 300 gigahertz or more, which is the millimeter wave band.
- epsilon iron oxide is a crystal in which a part of the Fe site of the crystal is replaced with a trivalent metal element such as aluminum (Al), gallium (Ga), rhodium (Rh), indium (In) or the like.
- the magnetic resonance frequency that is, the frequency of the electromagnetic wave to be absorbed when used as an electromagnetic wave absorbing material can be made different.
- a epsilon iron oxide gallium substitution that is, when the ⁇ -Ga x Fe 2-x O 3, the peak of absorption in a frequency band from 30 GHz by adjusting the substitution amount "x" up to about 150 GHz
- aluminum-substituted epsilon iron oxide that is, ⁇ -Al x Fe 2-x O 3
- substitution amount “x” it has an absorption peak in a frequency band of about 100 gigahertz to about 190 gigahertz.
- the type of the element to be substituted for the Fe site of epsilon iron oxide is determined so that the natural resonance frequency of the frequency to be absorbed by the electromagnetic wave absorbing sheet is obtained, and the absorption is adjusted by adjusting the substitution amount with Fe.
- the frequency of the electromagnetic wave can be set to a desired value.
- Epsilon iron oxide can be easily obtained since it is commercially available including some of the Fe sites in which metal substitution is performed.
- barium ferrite magnetic powder and strontium ferrite may be used as the magnetic iron oxide powder as the electromagnetic wave absorbing portion material having a magnetic resonance frequency used for the electromagnetic wave absorbing composition according to the present embodiment.
- a magnetic powder etc. can be used and the electromagnetic wave absorptive composition which absorbs electromagnetic waves of the high frequency band of a GHz zone or a millimeter wave zone, and an electromagnetic wave absorption sheet produced using this composition are realizable.
- the strontium ferrite it is preferable to use magnetic powder of magnetoplumbite type strontium ferrite.
- the magnetoplumbite-type strontium ferrite magnetic powder represented by the composition formula SrFe (12-x) Al x O 19 (x: 1.0 to 2.2) electromagnetic waves in the 76 GHz ⁇ 10 GHz band Can be absorbed effectively.
- the size (particle diameter) of the strontium ferrite one having a peak particle diameter of 1 ⁇ m or more of the laser diffraction scattering particle size distribution can be used, particularly from the viewpoint of electromagnetic wave absorption characteristics, and the peak particle diameter of the laser diffraction scattering particle size distribution Those having a size of 10 ⁇ m or more are preferable.
- resin binder As resin binder in the electromagnetic wave absorptive composition concerning this embodiment, resin materials, such as epoxy resin, polyester resin, polyurethane resin, acrylic resin, phenol resin, melamine resin, rubber resin, etc., are used. be able to.
- polyester-type urethane resin a compound obtained by epoxidizing hydroxyl groups at both ends of bisphenol A can be used as the epoxy resin.
- polyester-type urethane resin a polyether-type urethane resin, a polycarbonate-type urethane resin, an epoxy-type urethane resin etc. can be used as polyurethane-type resin.
- acrylic resin it is a methacrylic resin, and acrylic acid alkyl ester and / or methacrylic acid alkyl ester in which the carbon number of the alkyl group is in the range of 2 to 18 and functional group-containing monomer, these as needed And a functional group-containing methacrylic polymer obtained by copolymerizing the monomer and another modifying monomer copolymerizable therewith.
- SIS styrene-isobrene block copolymer
- SBS styrene-butadiene block copolymer
- EPDM ethylene-propylene-cobalt
- polyester resin as a binder from the viewpoint of dispersion after compounding the resin, since an electromagnetic wave absorbing sheet with high flexibility can be formed.
- glass transition temperature (Tg) ⁇ 10 ° C. to ⁇ 40 ° C. are preferably used. If the glass transition temperature is lower than -40 ° C., the resin is so soft that an electromagnetic wave absorbing sheet can not be formed. On the other hand, when the glass transition point is higher than -10 ° C., it is difficult to realize a sheet having sufficient flexibility and elasticity as an electromagnetic wave absorbing sheet formed because the resin becomes too hard. It is more preferable to use a resin binder having a glass transition temperature (Tg) in the range of -15.degree. C. to -30.degree.
- magnetic iron oxide powder 1a such as epsilon iron oxide powder is used as an electromagnetic wave absorbing material. It is important that the epsilon iron oxide powder is a fine nanoparticle with a particle diameter of several nm to several tens of nm, and that the magnetic iron oxide powder has a small particle diameter, so that it is important to disperse well in the electromagnetic wave absorbing composition. Become.
- the flexibility and the elasticity of the electromagnetic wave absorbing sheet can be favorably secured by dispersing the strontium ferrite magnetic powder in the electromagnetic wave absorbing sheet.
- the electromagnetic wave absorptive composition concerning this embodiment considers the utilization as an electromagnetic wave absorptive paint besides the case where it shape
- the acid value of the dispersant is 8 mg KOH / g to 46 mg KOH / g
- the amine value is 18 mg KOH / g to 44 mg KOH / g. It turned out that it is preferable.
- the binder resin when magnetic iron oxide powder is dispersed with a binder resin, the binder resin is appropriately adsorbed on the surface of the magnetic iron oxide powder, and the steric hindrance of the non-adsorbed free binder resin maintains the distance between the magnetic iron oxide powders. , Need to maintain the distribution.
- Iron oxide magnetic powder used as an electromagnetic wave absorbing material usually has a large number of alkaline active points and a small number of acidic active points.
- the binder resin it is preferable to use a binder resin having an acidic group or an acid salt among the above from the viewpoint of solubility in a solvent at the time of molding of an electromagnetic wave absorbing sheet or when used as an electromagnetic wave absorbing paint.
- a binder resin having an acid group or an acid salt is used to disperse the magnetic iron oxide powder having many alkaline active points on the surface, and the interaction between the two is too strong. Many binder resins will be adsorbed.
- FIG. 2 is an image view for explaining the function of the dispersing agent in the electromagnetic wave absorbing composition according to the present embodiment.
- FIG. 2 (a) shows a state in which a dispersing agent is contained together with a resinous binder
- FIG. 2 (b) shows a state in which the dispersing agent is not contained.
- the binder (polymer main chain) 1b having the above-mentioned acid group and acid salt (white squares in FIG. 2 (b)) has an alkaline active point ( The amount adsorbed on the magnetic iron oxide powder 1a having many black circles in FIG. 2 (b) increases, and the amount of binder resin in a free state decreases, so that the steric hindrance due to the binder resin can not be maintained.
- the powders 1a come close to each other to cause aggregation.
- the amount of binder resin used is increased to increase the amount of binder resin in a free state, the amount of iron oxide magnetic powder relatively decreases, so the electromagnetic wave absorbing ability may be reduced. .
- the binder resin is adsorbed to the surface of the magnetic iron oxide powder by using a dispersant having an acid value of 8 mg KOH / g to 46 mg KOH / g and an amine value of 18 mg KOH / g to 44 mg KOH / g.
- a dispersant having an acid value of 8 mg KOH / g to 46 mg KOH / g and an amine value of 18 mg KOH / g to 44 mg KOH / g.
- the amount of binder resin in a free state can be increased without increasing the amount of binder resin used, so an electromagnetic wave absorbing sheet or the like having sufficient flexibility and elasticity without reducing the electromagnetic wave absorbing ability
- An electromagnetic wave absorbing paint can be realized.
- part of the dispersant 1c blocks the alkaline active points (black circles in FIG. 2 (a)) of the magnetic iron oxide powder 1a, so the magnetic iron oxide powder 1a and the resin binder ( Appropriate amount of the binder 1b adsorbed to the magnetic iron oxide powder 1a and the free state binder 1b not adsorbed to the magnetic iron oxide powder 1a while suppressing the interaction with the polymer main chain) 1b It becomes.
- the electromagnetic wave absorbing composition steric hindrance is maintained by the resin binder 1b in a free state, aggregation and sedimentation of the composition can be suppressed and stability can be maintained, and the electromagnetic wave absorbing composition is used.
- the flexibility and elasticity of the electromagnetic wave absorbing sheet can be enhanced.
- the acid value and the amine value in one molecule are an acidic functional group such as a carboxyl group exhibiting an acid value, and an alkaline function exhibiting an amine value such as an amine group or an amide group.
- the acidic functional group of the dispersant is adsorbed on the surface of the magnetic iron oxide powder which is alkaline.
- the alkaline functional group of the dispersant interacts with the binder resin, in particular, the binder resin having an acidic group or an acid salt.
- the adsorption of the binder resin to the magnetic iron oxide powder is appropriately controlled, and as a result, steric hindrance due to the free binder resin can be maintained, and therefore aggregation of the composition for an electromagnetic wave absorber without increasing the amount of the resin binder. And sedimentation can be suppressed to improve the dispersibility.
- the solubility in the solvent becomes good, and the aggregation and sedimentation of the electromagnetic wave absorbing composition are suppressed to improve the dispersibility. be able to.
- the acid value of the dispersant used is less than 8 mg KOH / g, the interaction with the magnetic iron oxide powder becomes too weak, and adsorption of the binder resin to the magnetic iron oxide powder can not be suppressed, so that the free binder resin is used.
- the steric hindrance due to the above can not be maintained, and the magnetic iron oxide powder can not be dispersed, and the electromagnetic wave absorbing composition is aggregated.
- the dispersant is adsorbed too much to the magnetic iron oxide powder, so that the interaction between the binder resin and the magnetic iron oxide powder becomes weak, and the magnetic iron oxide powder of the binder resin is The adsorption of the magnetic iron oxide powder is too small, so that the plurality of magnetic iron oxide powders become easy to approach, and the electromagnetic wave absorbing composition is also aggregated.
- the amine value is larger than 44 mg KOH / g, the interaction between the dispersant and the binder resin becomes strong, so the interaction between the binder resin and the magnetic iron oxide powder becomes weak, and the magnetic iron oxide of the binder resin Since the adsorption to the powder is too small, the magnetic iron oxide powder can not be dispersed, and the electromagnetic wave absorbing composition is aggregated.
- the interaction between the dispersant and the binder resin becomes weak, so the adsorption of the binder resin to the magnetic iron oxide powder decreases, and the magnetic iron oxide powder is dispersed. And the electromagnetic wave absorbing composition is aggregated.
- the electromagnetic wave absorbing composition it is preferable to use a dispersant or an amphoteric dispersant in which both the acid value and the amine value satisfy predetermined requirements.
- the acid value is more preferably 24 mg KOH / g or more and 46 mg KOH / g or less.
- the acid value is the number of mg of potassium hydroxide required to neutralize free fatty acid, resin acid and the like contained in 1 g of the sample.
- the amine value is the number of mg of acid and equivalent potassium hydroxide required to neutralize the amount of 1 g of sample.
- the electromagnetic wave absorbing sheet of this embodiment is prepared by using an electromagnetic wave absorbing composition containing at least a magnetic iron oxide powder, a dispersing agent, and a resin binder, and coating the same with a predetermined thickness, followed by drying. After being subjected to calendering, an electromagnetic wave absorbing sheet is formed. Furthermore, by using a solvent for the electromagnetic wave absorbing composition, the aggregation and sedimentation of the magnetic iron oxide powder can be suppressed to improve the dispersibility. Calendering may be performed as necessary, and when the magnetic iron oxide powder has a volume content in a predetermined range in a state where the magnetic paint is dried, calendering may not be performed. Absent.
- the magnetic paint is prepared by blending magnetic iron oxide powder such as epsilon iron oxide powder, a dispersant having an acid value and an amine value within the predetermined range, a resin binder and a solvent.
- the produced magnetic paint is dispersed using a sand mill.
- a more favorable electromagnetic wave absorptive composition can be obtained by re-dispersing with a sand mill.
- a crosslinking agent can be blended together with a resin binder, and crosslinking may be performed.
- the magnetic paint may be previously dispersed using a sand mill after being kneaded using a kneader.
- An electromagnetic wave absorption sheet is produced using the electromagnetic wave absorptive composition produced in this way.
- the electromagnetic wave absorptive composition produced above is apply
- the resin sheet 2 as an example, a 38 ⁇ m-thick sheet of polyethylene terephthalate (PET) which has been subjected to a peeling treatment on the surface by a silicone coat can be used.
- An electromagnetic wave absorbing composition is applied onto the resin sheet 2 using a coating method such as a table coater method or a bar coater method.
- the electromagnetic wave absorbing composition in the wet state is dried and further calendered to form an electromagnetic wave absorbing sheet on the support.
- the thickness of the electromagnetic wave absorbing sheet can be controlled by the coating thickness, the conditions of calendering, and the like.
- the electromagnetic wave absorbing sheet 1 after the calendering treatment is peeled off from the resin sheet 2 to obtain the electromagnetic wave absorbing sheet 1 having a desired thickness.
- an electromagnetic wave absorbing composition is manufactured by the above-mentioned manufacturing method, and an electromagnetic wave absorbing sheet is manufactured using this electromagnetic wave absorbing composition, and changes in various properties depending on the acid value and the amine value of the dispersant are compared and compared. did.
- Electromagnetic wave absorption sheet Subsequently, the obtained electromagnetic wave absorbing composition is coated on a 38 ⁇ m-thick sheet of polyethylene terephthalate (PET) peeled off by silicon coating using a bar coater, and dried at 80 ° C.
- PET polyethylene terephthalate
- a sheet having a thickness of 400 ⁇ m was obtained.
- the sheet obtained in this manner was subjected to calendering at a temperature of 80 ° C. and a pressure of 150 kg / cm to obtain an electromagnetic wave absorbing sheet having a thickness of 300 ⁇ m.
- DISPERBYK-142 used as a dispersing agent is a high molecular weight wetting and dispersing agent for solvent-type paints manufactured by Bick Chemie Japan Ltd.
- Byron UR 8700 used as a resin binder is a polyester-based urethane resin manufactured by Toyobo Co., Ltd.
- the electromagnetic wave absorbing sheets of Examples 2 to 4 in which the acid value and the amine value are in the numerical ranges described in the present embodiment are different
- the electromagnetic wave absorbing sheets of Comparative Examples 1 to 4 in which at least one of the acid value and the amine value was out of the above numerical range were produced.
- the dispersant used in preparing each of the electromagnetic wave absorbing sheets, and the numerical values of the acid value and the amine value are as follows.
- Example 2 Dispersant ANTI-TERRA-U (trade name) Acid value: 24 mg KOH / g, amine value: 19 mg KOH / g
- Example 3 Dispersant DISPERBYK-2013 (trade name) Acid value: 8 mg KOH / g, amine value: 18 mg KOH / g
- Example 4 Dispersant BYK-9076 (trade name) Acid value: 38 mg KOH / g, amine value: 44 mg KOH / g.
- Dispersant DISPERBYK-140 (trade name) Acid value: 73 mg KOH / g, amine value: 76 mg KOH / g Comparative Example 2
- Dispersant DISPERBYK-145 (trade name) Acid value: 76 mg KOH / g, amine value: 71 mg KOH / g Comparative Example 3
- Dispersant DISPERBYK-2155 (trade name) Acid value: 0 mg KOH / g, amine value: 48 mg KOH / g Comparative Example 4
- Dispersant DISPERBYK-185 (trade name) Acid value: 0 mg KOH / g, amine value: 17 mg KOH / g.
- the dispersants used in Examples 2 to 4 and Comparative Examples 1 to 4 are all the same as the dispersants used in Example 1, but the high molecular weight wet dispersion for solvent type paints manufactured by Bick Chemie Japan Ltd. It is an agent.
- the electromagnetic wave absorptive composition 2 using strontium ferrite as magnetic iron oxide powder was produced, and the electromagnetic wave absorptive sheet of Example 5 was produced using this electromagnetic wave absorptive composition 2.
- Example 5 Magnetic paint component 2 ⁇ A magnetic paint component 2 was produced in the same manner as in Example 1 except that strontium ferrite magnetic powder was used as the magnetic iron oxide powder.
- Solvent Methyl ethyl ketone / toluene 95 parts ( 1/1 mixed solvent).
- the magnetic paint component 2 was dispersed in a disc-type sand mill having an inner volume of 2 L using zirconia beads of 0.5 mm in diameter as a dispersion medium.
- a magnetic paint component 46 parts of a polyurethane binder Byron UR 8700 (trade name), Tg: -22 ° C)
- the obtained electromagnetic wave absorbing composition is coated on a 38 ⁇ m-thick sheet of polyethylene terephthalate (PET) peeled off by silicon coating using a bar coater, and dried at 80 ° C.
- PET polyethylene terephthalate
- a sheet with a thickness of 1400 ⁇ m was obtained.
- the sheet thus obtained was subjected to calendering at a temperature of 80 ° C. and a pressure of 150 kg / cm to obtain an electromagnetic wave absorbing sheet having a thickness of 1362 ⁇ m.
- Byron 55 SS used as a resin binder in Example 6 is an amorphous polyester resin manufactured by Toyobo Co., Ltd.
- Byron UR 6100 used as a resin binder in Example 7 is a polyester-based urethane resin manufactured by Toyobo
- Average particle size The average particle size was measured by mixing with a stirrer using ⁇ magnetic paint component 1 ⁇ and ⁇ magnetic paint component 2 ⁇ in each example and comparative example, and having a solid component concentration of 52% by weight was the subject of measurement.
- a concentrated particle size analyzer FPAR-1000 (product name) manufactured by Otsuka Electronics Co., Ltd., an ND filter: 10%, a dilution solvent: MEK, and a dilute probe were used.
- the measurement results show that when the average particle diameter is 150 nm or less, the evaluation of “o” is sufficiently dispersed, and when the average particle diameter exceeds 150 nm, the dispersion is insufficient, “x” It was evaluated.
- Reflection density The reflection density is measured by applying an applicator with a wet thickness of 60 ⁇ m on a PET film using ⁇ electromagnetic wave absorbing composition ⁇ in each of the Examples and Comparative Examples, and using a naturally dried coating film as a measurement target used.
- a reflection densitometer Macbeth RD-920 (product name) manufactured by Sakata Inx Engineering Co., Ltd. was used.
- the measurement results were such that the reflection density was 1.9 or more as “o” evaluation, and the reflection density was less than 1.9 as “x” evaluation.
- FIG. 3 is a view showing a method of evaluating the flexibility of the electromagnetic wave absorbing sheet.
- a ribbon-shaped ⁇ electromagnetic wave absorbing sheet ⁇ having a length of 100 mm and a width of 20 mm is prepared in each of the examples and the comparative examples, and as shown in FIG. It curved so that the both ends of the length direction may overlap centering on the middle part, and the external force which maintains this state was calculated.
- the thickness of the produced electromagnetic wave absorption sheet of an Example, a comparative example, and each was shown in Table 1 mentioned later.
- the electromagnetic wave absorbing sheet 1 to be measured is disposed on the measuring table 21 of the electronic balance, and the weight of the electromagnetic wave absorbing sheet in a state where no external force is applied is measured. Thereafter, as shown in FIG. 3, the weight applied to the electronic balance in a state of being deformed by applying the external force 23 is measured, and the weight of the weight of the electromagnetic wave absorbing sheet is removed from the obtained measurement result.
- the added weight required to keep the electromagnetic wave absorbing sheet in a curved state is known.
- a plate member 22 as shown in FIG. 3 is disposed on the upper side of the electromagnetic wave absorbing sheet 1, and the vertically lower side with respect to the plate member 22.
- L 10 mm
- d 10 mm
- the magnitude of the external force 23 was measured as weight, and the value obtained by dividing this by the cross-sectional area D (unit: mm 2 ) of the electromagnetic wave absorbing sheet was taken as the flexibility evaluation value F (g / mm 2 ).
- the electromagnetic wave absorption sheet in each Example and a comparative example WHEREIN The electromagnetic wave absorption sheet produced without adding a dispersing agent as a reference is produced, the flexibility evaluation value in this reference is set to F0, and a dispersing agent is added and produced
- the effect numerical value (%) of this dispersing agent is a numerical value indicating the degree of improvement in flexibility by using the dispersing agent for the electromagnetic wave absorbing sheet generated without using the dispersing agent.
- an electromagnetic wave absorbing sheet produced by mixing magnetic iron oxide powder, which is a fine metal powder, into a resin binder as shown in this embodiment if the volume content of magnetic iron oxide powder is the same, The higher the degree of dispersion, the higher the flexibility of the electromagnetic wave absorbing sheet. For this reason, the degree of dispersion of the magnetic iron oxide powder by the dispersant is measured purely by the above-mentioned measuring method.
- the flexibility evaluation value is obtained by using a dispersant having an acid value and an amine value within the ranges defined as the present invention.
- the size of the external force required for bending to a predetermined shape is about 1/2 compared with the case where no dispersant is used, and the electromagnetic wave absorbing sheet is softened by the dispersant. I understand.
- the measurement was carried out at a tension rate of 10 mm / min to a maximum of 100 mm under an environment of a temperature of 23 ° C. and a humidity of 50% RH using a tensile tester TRE-1 kN manufactured by Minebea Mitsumi Co., Ltd.
- the amount of elongation of the sheet the amount of elongation in a state where the maximum tensile force (N / mm 2 ) is applied to the sheet at the time of tensile test Expressed as a percentage to 30 mm.
- the electromagnetic wave absorbing sheet of Example 1 indicated by the solid line 31 continues to expand in a state of a tensile force of about 0.1 N / mm 2 and is stable even when the elongation amount is 100%, that is, the total length of 30 mm becomes 60 mm. showed that.
- the maximum tensile force was 0.11 N / mm 2 .
- the electromagnetic wave absorbing sheet manufactured using the electromagnetic wave absorbing composition of the range of the present invention in which the acid value and the amine value of the dispersant are within the predetermined range has high elasticity. did it.
- each ⁇ electromagnetic wave absorbing composition ⁇ was placed in a 9 cc screw bottle and allowed to stand for 24 hours.
- the electromagnetic wave absorbing composition Assuming that the electromagnetic wave absorbing composition is used as an electromagnetic wave absorbing paint, the electromagnetic wave absorbing material does not cause sedimentation or the like for a certain period of time from preparation of the paint to actual application to an object. It is necessary for the magnetic iron oxide powder to maintain good dispersion. Also in this respect, it has been confirmed that high practicability can be secured by preparing the electromagnetic wave absorbing composition using the dispersant of the acid value and the amine value specified in the present application.
- the degree of reduction of the external force in the case where each dispersant is contained is evaluated using the external force in the state where the dispersant is not used as a reference as an evaluation value of flexibility. It was measured as a value.
- the relationship between the thickness of the electromagnetic wave absorbing sheet and the absorption characteristics of the electromagnetic wave in the case of containing the dispersing agent and the case of not containing the dispersing agent was also confirmed.
- the absorption characteristics of the electromagnetic waves were measured by the free space method. Specifically, it is carried out using a millimeter wave network analyzer N5250C (trade name) manufactured by Agilent Technologies, Inc., and using one port, a transmitting and receiving antenna from the transmitting and receiving antenna via the dielectric lens to the electromagnetic wave absorbing sheet
- the input wave (millimeter wave) is irradiated, the radio wave transmitted through the electromagnetic wave absorbing sheet is received by the receiving antenna arranged on the back side, the intensity of the irradiation wave is compared with the intensity of the reception wave, and the attenuation degree is dB I asked.
- the thickness of the electromagnetic wave absorbing sheet is converted to 4.0 mm in comparison between the electromagnetic wave absorbing sheet of Example 1 and the electromagnetic wave absorbing sheet containing no dispersant serving as a reference in the electromagnetic wave absorbing sheet of Example 1.
- the electromagnetic wave absorption characteristic of the electromagnetic wave absorption sheet of Example 1 was 20 dB, and the electromagnetic wave absorption characteristic of the electromagnetic wave absorption sheet of the reference was 21 dB.
- the absorption characteristics of the electromagnetic wave hardly change due to the presence or absence of the dispersant.
- the inventors further confirmed the degree to which the dispersing effect of the dispersant contained in the numerical value range of the acid value and the amine value specified in the present application is maintained with respect to [precipitation] in the above evaluation result.
- Example 1 the electromagnetic wave absorbing composition of Example 1 was placed in a 9 cc screw bottle and left in the same manner as described above, and the average particle size of epsilon iron oxide powder was measured after a predetermined time elapsed.
- FIG. 5 shows the relationship between the standing time and the average particle size of epsilon iron oxide powder.
- the average particle diameter of epsilon iron oxide powder is substantially constant between 90 and 100 nm for at least 86 hours from the start of standing. Was confirmed.
- the electromagnetic wave absorbing composition disclosed in the present application has high practicability as an electromagnetic wave absorbing paint.
- the electromagnetic wave absorbing composition according to the present embodiment includes the magnetic iron oxide contained as an electromagnetic wave absorbing material by using a dispersant having an acid value and an amine value within a predetermined numerical range. It has been confirmed that the high dispersibility of the powder can be maintained for a long time.
- an electromagnetic wave absorbing sheet excellent in flexibility and elasticity can be obtained by preparing an electromagnetic wave absorbing sheet using the electromagnetic wave absorbing composition according to the present embodiment, and the electromagnetic wave according to the present embodiment.
- the absorbing composition itself can also be suitably used as an electromagnetic wave absorbing paint.
- the electromagnetic wave absorption sheet made only from the electromagnetic wave absorption layer which absorbs electromagnetic waves produced from the electromagnetic wave absorptive composition was illustrated and explained.
- the invention disclosed in the present application when producing the electromagnetic wave absorbing sheet, as a laminate of the electromagnetic wave absorbing layer and the resin layer to be the base, as long as the high flexibility and elasticity of the electromagnetic wave absorbing layer are not impaired. In this case, the durability and ease of handling of the electromagnetic wave absorbing sheet are improved. Further, by forming a laminate of the electromagnetic wave absorbing layer and the adhesive layer, it can be realized as an electromagnetic wave absorbing sheet which can be easily fixed to the place of arrangement.
- it can be realized as a reflection type electromagnetic wave absorbing sheet that reflects electromagnetic waves by laminating with a reflection layer having a certain or more reflection characteristics without impairing the flexibility and elasticity of the electromagnetic wave absorption layer. it can.
- the electromagnetic wave absorbing composition disclosed in the present application and an electromagnetic wave absorbing sheet produced using this electromagnetic wave absorbing composition are useful as an absorbing paint and absorbing sheet for absorbing electromagnetic waves in a high frequency band higher than the millimeter wave band. is there.
Abstract
Description
[電磁波吸収シート]
図1は、本実施形態にかかる電磁波吸収性組成物を用いて形成された電磁波吸収シートの構成を説明する断面図である。
本実施形態にかかる電磁波吸収シートでは、磁気共鳴周波数を有する磁性酸化鉄粉として、イプシロン酸化鉄の磁性粉を用いている。
本実施形態にかかる電磁波吸収性組成物における樹脂製バインダーとしては、エポキシ系樹脂、ポリエステル系樹脂、ポリウレタン系樹脂、アクリル系樹脂、フェノール系樹脂、メラミン系樹脂、ゴム系樹脂などの樹脂材料を用いることができる。
本実施形態にかかる電磁波吸収性組成物では、上述のように、電磁波吸収材料としてイプシロン酸化鉄粉などの磁性酸化鉄粉1aを用いる。イプシロン酸化鉄粉は粒径が数nmから数十nmの微細なナノ粒子であるなど、磁性酸化鉄粉は粒子径が小さいために、電磁波吸収性組成物内において良好に分散させることが重要となる。
ここで、本実施形態にかかる電磁波吸収シートの製造方法の一例について説明する。
以下、上記の作製方法によって電磁波吸収性組成物を作製し、さらにこの電磁波吸収性組成物を用いて電磁波吸収シートを作製して、分散剤の酸価とアミン価による諸特性の変化について比較検討した。
{磁性塗料成分1}
まず、以下の材料を攪拌機で混合し、磁性塗料成分1を作製した
磁性酸化鉄粉 イプシロン酸化鉄磁性粉 100部
(平均粒径30nm)
分散剤 DISPERBYK-142(商品名) 15部
酸価:46mgKOH/g、アミン価:43mgKOH/g
溶媒 メチルエチルケトン/トルエン 95部
(=1/1混合溶剤)。
{電磁波吸収性組成物}
この磁性塗料成分1を径0.5mmのジルコニアビーズを分散媒体とし、内容量が2Lのディスク型サンドミルで分散した。このようにして得た分散塗料を攪拌機で攪拌しながら、以下の材料を配合し、上記と同じ条件で分散して電磁波吸収性組成物を得た
磁性塗料成分1 100部
バインダー ポリウレタンバインダー 46部
(バイロンUR8700(商品名)、Tg:-22℃)
溶媒(希釈) メチルエチルケトン/トルエン 120部
(=1/1混合溶剤)。
{電磁波吸収シート}
続いて、得られた電磁波吸収性組成物を、シリコンコートにより剥離処理された厚さ38μmのポリエチレンテレフタレート(PET)のシート上に、バーコータを用いて塗布し、湿潤状態において80℃で1440分乾燥後、厚さ400μmのシートを得た
こうして得られたシートに温度80℃、圧力150kg/cmでカレンダ処理を行い、厚さ300μmの電磁波吸収シートを得た。
分散剤 ANTI-TERRA-U(商品名)
酸価:24mgKOH/g、アミン価:19mgKOH/g
<実施例3>
分散剤 DISPERBYK-2013(商品名)
酸価: 8mgKOH/g、アミン価:18mgKOH/g
<実施例4>
分散剤 BYK-9076(商品名)
酸価:38mgKOH/g、アミン価:44mgKOH/g。
分散剤 DISPERBYK-140(商品名)
酸価:73mgKOH/g、アミン価:76mgKOH/g
<比較例2>
分散剤 DISPERBYK-145(商品名)
酸価:76mgKOH/g、アミン価:71mgKOH/g
<比較例3>
分散剤 DISPERBYK-2155(商品名)
酸価: 0mgKOH/g、アミン価:48mgKOH/g
<比較例4>
分散剤 DISPERBYK-185(商品名)
酸価: 0mgKOH/g、アミン価:17mgKOH/g。
{磁性塗料成分2}
磁性酸化鉄粉としてストロンチウムフェライト磁性粉を用いた以外は実施例1と同じとして磁性塗料成分2を作製した。
磁性酸化鉄粉 ストロンチウムフェライト磁性粉 100部
(平均粒径5μm)
分散剤 DISPERBYK-142(商品名) 15部
酸価:46mgKOH/g、アミン価:43mgKOH/g
溶媒 メチルエチルケトン/トルエン 95部
(=1/1混合溶剤)。
{電磁波吸収性組成物2}
この磁性塗料成分2を径0.5mmのジルコニアビーズを分散媒体とし、内容量が2Lのディスク型サンドミルで分散した。このようにして得た分散塗料を攪拌機で攪拌しながら、以下の材料を配合し、上記と同じ条件で分散して電磁波吸収性組成物を得た
磁性塗料成分2 100部
バインダー ポリウレタンバインダー 46部
(バイロンUR8700(商品名)、Tg:-22℃)
溶媒(希釈) メチルエチルケトン/トルエン 120部
(=1/1混合溶剤)。
{電磁波吸収シート2}
続いて、得られた電磁波吸収性組成物を、シリコンコートにより剥離処理された厚さ38μmのポリエチレンテレフタレート(PET)のシート上に、バーコータを用いて塗布し、湿潤状態において80℃で1440分乾燥後、厚さ1400μmのシートを得た。こうして得られたシートに温度80℃、圧力150kg/cmでカレンダ処理を行い、厚さ1362μmの電磁波吸収シートを得た。
<実施例6>
磁性塗料成分1 100部
バインダー ポリエステルバインダー 46部
(バイロン55SS(商品名)、Tg:-15℃)
溶媒(希釈) メチルエチルケトン/トルエン 127部
(=1/1混合溶剤)
<実施例7>
磁性塗料成分1 100部
バインダー ポリウレタンバインダー 44部
(バイロンUR6100(商品名)、Tg:-30℃)
溶媒(希釈) メチルエチルケトン/トルエン 118部
(=1/1混合溶剤)
なお、実施例6に樹脂製バインダーとして用いたバイロン55SSは、東洋紡株式会社製の非晶性ポリエステル樹脂である。また、実施例7に樹脂製バインダーとして用いたバイロンUR6100は、東洋紡株式会社製のポリエステル系ウレタン樹脂である。
平均粒子径の測定は、各実施例、比較例における、{磁性塗料成分1}、および、{磁性塗料成分2}を用いて攪拌機で配合して作製した、固形成分濃度が52重量%のものを測定対象とした。
反射濃度の測定は、各実施例、比較例共に、{電磁波吸収性組成物}を用いて、PETフィルム上にWet厚60μmのアプリケーターで塗布した後、これを自然乾燥した塗布膜を測定対象として使用した。
図3は、電磁波吸収シートの可撓性の評価方法を示す図である。
電磁波吸収シートの伸び(弾性)については、各実施例、および、比較例として作製された{電磁波吸収シート}を、長さ30mm、幅20mmのリボン状に形成して測定試料とした。
各実施例、および、各比較例において、それぞれの{電磁波吸収性組成物}について、9ccのスクリュ瓶に入れて24時間放置した。
以上、実施例1~4、比較例1~4について、それぞれで使用した分散剤の酸価とアミン価の値、[平均粒子径][反射濃度][可撓性][伸び][沈降]についての評価結果を下記表1にまとめた。
1a イプシロン酸化鉄(磁性酸化鉄粉)
1b バインダー
1c 分散剤
Claims (5)
- 磁気共鳴周波数を有する磁性酸化鉄粉と、バインダー樹脂と、分散剤とを含む電磁波吸収性組成物であって、
前記分散剤の酸価が8mgKOH/g以上46mgKOH/g以下、アミン価が18mgKOH/g以上44mgKOH/g以下であることを特徴とする電磁波吸収性組成物。 - 前記バインダー樹脂のガラス転移温度(Tg)が-10℃から-40℃である、請求項1に記載の電磁波吸収性組成物。
- 前記磁性酸化鉄粉がイプシロン酸化鉄、または、ストロンチウムフェライトの少なくともいずれか1種である、請求項1または2に記載の電磁波吸収性組成物。
- 前記イプシロン酸化鉄のFeサイトの一部が3価の金属原子で置換されている、請求項3に記載の電磁波吸収性組成物。
- 請求項1~4のいずれかに記載の電磁波吸収性組成物により構成された電磁波吸収層を備えたことを特徴とする電磁波吸収シート。
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WO2020230448A1 (ja) * | 2019-05-14 | 2020-11-19 | 富士フイルム株式会社 | 電波吸収体及びコンパウンド |
WO2021033517A1 (ja) * | 2019-08-19 | 2021-02-25 | 国立大学法人 東京大学 | 電波吸収体フィルム、及びその製造方法 |
JPWO2021039787A1 (ja) * | 2019-08-26 | 2021-03-04 | ||
JP2022003133A (ja) * | 2019-08-26 | 2022-01-11 | 国立大学法人富山大学 | 微粒子吸着防止ポリマー |
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Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01106317A (ja) * | 1987-10-19 | 1989-04-24 | Konica Corp | 磁気記録媒体 |
JP2002188031A (ja) | 2000-12-19 | 2002-07-05 | Dainippon Printing Co Ltd | 電波吸収体用インキ組成物及び電波吸収体 |
JP2002299876A (ja) * | 2001-03-30 | 2002-10-11 | Dainippon Printing Co Ltd | 携帯型電話機用電波吸収性包装体 |
JP2002312922A (ja) * | 2001-04-18 | 2002-10-25 | Fuji Photo Film Co Ltd | 磁気記録媒体 |
JP2008060484A (ja) | 2006-09-01 | 2008-03-13 | Univ Of Tokyo | 電波吸収性磁性結晶および電波吸収体 |
JP2009149745A (ja) | 2007-12-19 | 2009-07-09 | Taiyo Ink Mfg Ltd | ペースト組成物 |
JP2011029620A (ja) * | 2009-06-24 | 2011-02-10 | Univ Of Tokyo | 磁性薄膜の製造方法、磁性薄膜及び磁性体 |
JP2011233834A (ja) | 2010-04-30 | 2011-11-17 | Shachihata Inc | 電波吸収体 |
JP2016062963A (ja) * | 2014-09-16 | 2016-04-25 | セイコーエプソン株式会社 | 電子基板またはデバイスの製造方法、電子基板およびデバイス |
JP2016098243A (ja) | 2014-11-18 | 2016-05-30 | 防衛装備庁長官 | 電波吸収体用塗料組成物及び電波吸収体 |
JP2016135737A (ja) | 2015-01-19 | 2016-07-28 | 国立大学法人 東京大学 | ε酸化鉄を含む配向体とその製造方法、並びに製造装置 |
-
2018
- 2018-06-22 EP EP18820169.3A patent/EP3643752A1/en not_active Withdrawn
- 2018-06-22 TW TW107121408A patent/TW201906937A/zh unknown
- 2018-06-22 WO PCT/JP2018/023865 patent/WO2018235952A1/ja active Application Filing
- 2018-06-22 JP JP2019525711A patent/JPWO2018235952A1/ja active Pending
Patent Citations (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01106317A (ja) * | 1987-10-19 | 1989-04-24 | Konica Corp | 磁気記録媒体 |
JP2002188031A (ja) | 2000-12-19 | 2002-07-05 | Dainippon Printing Co Ltd | 電波吸収体用インキ組成物及び電波吸収体 |
JP2002299876A (ja) * | 2001-03-30 | 2002-10-11 | Dainippon Printing Co Ltd | 携帯型電話機用電波吸収性包装体 |
JP2002312922A (ja) * | 2001-04-18 | 2002-10-25 | Fuji Photo Film Co Ltd | 磁気記録媒体 |
JP2008060484A (ja) | 2006-09-01 | 2008-03-13 | Univ Of Tokyo | 電波吸収性磁性結晶および電波吸収体 |
JP2009149745A (ja) | 2007-12-19 | 2009-07-09 | Taiyo Ink Mfg Ltd | ペースト組成物 |
JP2011029620A (ja) * | 2009-06-24 | 2011-02-10 | Univ Of Tokyo | 磁性薄膜の製造方法、磁性薄膜及び磁性体 |
JP2011233834A (ja) | 2010-04-30 | 2011-11-17 | Shachihata Inc | 電波吸収体 |
JP2016062963A (ja) * | 2014-09-16 | 2016-04-25 | セイコーエプソン株式会社 | 電子基板またはデバイスの製造方法、電子基板およびデバイス |
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