TW200806468A - Resin coated metal plate having excellent electromagnetic wave shielding property - Google Patents

Abstract

To provide a new resin-coated metal plate which can exert excellent performance of shielding electromagnetic waves by improving the conductivity of the resin-coated metal plate and preferably exert the good characteristics even under light-contact conditions. The plate is surface-coated with a resin film, and the resin film meets the condition (1) PPIt ≥ 70 (wherein, PPIt is the number of peak-trough counts, with the half of the peak count level (2H) equal to the thickness t (μm) of the resin film, for PPI (Peaks Per Inch) defined by SAE J911-1986).

Description

(1) In the present invention, the present invention relates to a resin-coated metal sheet excellent in electromagnetic shielding properties (electrical conductivity). The resin-coated metal sheet of the present invention can exhibit excellent electrical conductivity even under light contact (at a light pressure) of, for example, a pressure of about 10 to 12 g/mm 2 , and is therefore suitable for use in, for example, electronic, electrical, and optical equipment (hereinafter sometimes). A frame made of a frame or the like represented by an electronic device. [Prior Art] With the advancement of the high-performance and miniaturization of electronic devices, electronic devices are required to prevent electromagnetic waves generated inside the electronic devices from being exposed to the outside or electromagnetic waves intruding from the outside of the electronic devices. The frame has excellent electromagnetic shielding. In order to improve the electromagnetic shielding of the electronic device housing, it is recommended to use a material having excellent conductivity, such as the electric mining record steel plate. Therefore, although it is possible to attenuate Φ, for example, electromagnetic waves leaking from the gap between the steel sheets, there is a problem that leakage of electromagnetic waves such as from the air holes and the wiring holes cannot be effectively prevented. On the other hand, in Japanese Patent Laid-Open No. 2005-21 Japanese Laid-Open Patent Publication No. 572 discloses a resin-coated metal sheet in which a magnetic coating film containing an electromagnetic wave absorbing additive such as magnetic powder is coated on a back surface of a steel sheet (the inner side surface of the casing) at a predetermined thickness. Therefore, it is considered that the electromagnetic wave generated inside the casing is absorbed by the above-described metal plate multiple reflection or the like, so that the effect of attenuating electromagnetic waves leaking from the air hole or the like to the outside of the casing can be finally achieved. In the following, the following technique is disclosed in Japanese Laid-Open Patent Publication No. 2004-158810, the Japanese Patent Publication No. 2005-23 853, and the Japanese Patent Publication No. 2004-277876. By controlling the thickness of the resin film of the resin-coated metal sheet, the surface roughness, and the roughness of the metal plate, the conductivity is improved, thereby improving the electromagnetic wave shielding property. In Japanese Laid-Open Patent Publication No. 2004-158018, a surface-treated steel sheet having improved electromagnetic wave shielding properties by appropriately controlling the relationship between the center line average roughness (Ra) and the average thickness of the film after formation of the film is disclosed. . Here, the relationship between the Ra and the average thickness of the film is determined according to the following knowledge, that is, the conductivity of the film is determined by the film thickness of the convex portion in which the film thickness is relatively thin, and when the average film thickness is the same, the Ra is increased. The conductivity of the film is improved. In Japanese Laid-Open Patent Publication No. 2005_23 8 5 3 5, a steel sheet which is subjected to temper rolling by appropriately controlling the surface roughness Ra and PPI and using an electric discharge machining roll as a plated raw material sheet is disclosed. Conductive surface treated steel sheet. In the same manner as in the above-mentioned Japanese Patent Publication No. 20 04-156081, the conductivity of the film is determined by the film thickness of the convex portion. Further, it is described that when the Ra is the same level, the plated raw material plate having a high PPI exceeds the cut line peak in the average line direction of the roughness curve as compared with the plated raw material plate having a low PPI. Since the number is increased, the convex portion of the surface of the steel sheet is treated with a high PPI, and there is more a portion having a thin portion of the local film thickness, thereby improving conductivity. In Japanese Laid-Open Patent Publication No. 2004-277876, it is disclosed that a good grounding is ensured by appropriately controlling the surface roughness (arithmetic mean coarseness - 6 - (3) (3) 200,806,468 roughness Ra) of the surface-treated steel sheet. Sexual surface treatment of zinc-based plated steel. The case where the grounding property can be improved by appropriately controlling the filter center line waveform (Wca) is also described. With the high performance of electronic devices, the demand for improving the shielding of electromagnetic waves is greatly increased. In addition, in order to reduce the cost, it is strongly desired to provide a resin-coated metal sheet which can eliminate the simplification of the electromagnetic wave shielding member such as a gasket and a copper spring, and which exhibits excellent electrical conductivity and electromagnetic wave shielding property under light contact. In view of the above, an object of the present invention is to provide a novel resin-coated metal sheet which can exhibit excellent electromagnetic shielding properties by improving the conductivity of a resin-coated metal sheet. Good characteristics can also be achieved under light contact. The resin-coated metal sheet of the present invention which solves the above-described problems is a resin-coated metal sheet coated with a resin film on the surface of a metal sheet, and the resin film satisfies the requirements of the following (1), and PPIt^ 70 PPIt indicates In PPI (Peaks Per Inch) described in SAE J911-19, the number of peak-to-valley counts when 1/2 of the peak value (2H) is taken as the thickness ί(μιη) of the resin film. In a preferred embodiment, the glass transition point of the resin film (200806468 (4)

Tg) is below 60 °C. In a preferred embodiment, the metal sheet is a zinc and iron group alloy plated steel sheet. In a preferred embodiment, the metal sheet is an alloyed molten steel sheet. Since the resin-coated metal sheet of the present invention has the above-described configuration, it is possible to improve the electrical conductivity under light contact and achieve good electromagnetic wave shielding. [Inventors] The present inventors have provided contact with, for example, a pressure of about 10 to 12 g/mm 2 ( Under light pressure, it is also possible to exhibit good electrical conductivity, and the resin having good electromagnetic shielding properties is coated with a metal plate, and the side surfaces of both the resin film and the metal plate (plate) are inspected. The inventors have conducted a plurality of basic experiments, and the results clearly show that • the fat film is related, and the deformation energy of the resin film is larger (that is, the resin film), and the conductivity is improved. In addition, it is found that in order to promote the resin film, (1) the shape of the resin film is controlled to be the most effective, and the number of peaks and valleys exceeding the film thickness t per one inch is set, and the individual index is described in detail later, and (2) According to the shape of the resin film, it is also effective to control the glass transition point (Tg) of the resin film, thereby completing the invention. On the other hand, it has been found that it is related to the metal plate (raw material plate) and compared with the conventional electrogalvanized steel sheet. It is best to use zinc and iron elements (galvanized by Fe, such as the opaque light-shielding material and the softer deformation of the tree PPIt). The local alloy, Co (5) 200806468, N i ) alloying A plated steel sheet (hereinafter sometimes referred to as "zinc-iron alloy-plated steel sheet"), in which alloying melting by alloying by zinc and iron is more preferable in consideration of cost reduction. Galvanized steel. In order to obtain a resin-coated metal sheet having excellent electromagnetic shielding properties, as described above, it is possible to carry out a method for promoting the deformation of the resin film to further improve electromagnetic shielding properties, and it is preferable to further appropriately control the type of the metal plate. In the present specification, "the electromagnetic wave shielding property is good, and it is a characteristic (action effect) that can prevent leakage of electromagnetic waves regardless of the inside and outside of the electronic device. On the other hand, in the present specification, "electromagnetic wave absorption" It is a characteristic required for a metal plate (raw material plate), etc. in order to improve the characteristic of the electromagnetic shielding property. The metal plate excellent in electromagnetic wave absorption can reduce the leakage electromagnetic wave from the air hole and the wiring hole, for example, and it is excellent in electromagnetic shielding. In the following, the method for promoting the deformation of the resin film and the optimum type of the metal plate will be described in detail. (The method for promoting the deformation of the resin film) (1) The shape control of the resin film (PPIt 2 70 of the resin film) In the present invention, in order to embody the technical idea that "the deformation energy of the resin film is larger (the hardness of the resin film is smaller) and the conductivity is improved", the parameter of PPIt described below is determined. In order to promote the deformation of the resin film. The method of properly controlling the hardness of the resin film itself is most effective, -9 - (6) 200806468 but It is extremely difficult to measure the hardness of the resin film coated on the metal plate. Therefore, in the present invention, the hardness of the resin film is not controlled, but the shape of the resin film (here, PPIt) is controlled. The resin-coated metal plate is generally When the thickness of the resin film is large, the unevenness of the metal plate is not affected. However, when the resin film is thin, the unevenness of the metal plate has a large influence on the thickness of the resin film, and the resin film is thinned at the convex portion of the metal plate, and the thickness of the resin film tends to be small. It varies depending on the position. 0 PPIt is obtained by converting the peak value of PPI (Peaks Per Inch) normalized in SAE J91 1-JUN86 (1 98 6 ) in the United States to the thickness t ( μιη ) of the resin film. The index indicating the deformation energy of the resin film is determined by the inventors. The difference between the SAE standard and the PPIt specified in the present invention will be described below with reference to Fig. 1. First, the PPI of the SAE standard refers to the extraction curve f. The average line of (x) sets a certain reference water® quasi-Η in both directions of positive (+) negative (-) (so the width of the reference level between positive and negative = 2H) will exceed the negative When the quasi-level (-H, valley portion) exceeds the positive reference level (+H, peak portion), it is recorded as "1 count, ', every 1 inch (25.4 mm) count. Mesh (peak-to-valley count) number). Here, the width (2H) of the reference level between positive and negative is called the peak 値 count level, and is fixed 値, which is usually set to 2H = 50pinch. In contrast, the PPIt specified in the present invention does not make the reference level between positive and negative. The width (2H) is set as the fixed crucible as described above, but based on the thickness t (μπι) of the resin film. That is, in Fig. 1, by setting H = t, -10-(7)(7)200806468 for PPIt, the number of peak-to-valley counts exceeding the thickness t of the resin film was measured. In this case, it is considered that a portion (conduction point) capable of exhibiting conductivity in the uneven portion of the resin film is a peak portion (convex portion) having a thin thickness of the resin film, and a concave portion having a thick thickness of the resin film does not become a conduction point' Thus set. Further, in t, the average thickness of the resin layer was determined by the method described later, and the crucible was used. In Fig. 1, the horizontal axis represents the measurement distance, and the extraction curve is the unevenness of the surface of the resin film covering the metal plate. According to the present invention, the number of peak-to-valley counts according to the thickness t of the resin film is measured so that the number of peak portions having a small thickness of the resin film is increased. Therefore, compared with the conventional method using PPI, it is possible to evaluate the sum with high precision. The relationship of electrical conductivity. In other words, in the method of using the PPI of the SAE standard, the convex portion having a thick film thickness of the resin film exceeds a predetermined peak value level (2H, for example, in the above-mentioned Japanese Patent Publication No. 2005-238535). ) are all counted. However, the conductivity is determined by the thickness of the film of the convex portion (peak portion) having a small thickness of the resin film, and the peak portion of the thickness of the resin film does not become a conduction point. Therefore, only the peak is measured regardless of the thickness of the resin film. In the above method of the number of valley counts, the relationship with the conductivity cannot be accurately grasped. On the other hand, in the present invention, as described above, "PPIt" which measures the number of peak-to-valley counts according to the thickness of the resin film is used as an index of conductivity, so that the portion to be a conduction point can be accurately grasped. The resin film which is thinly covered in the conduction point portion (peak portion) is very soft compared to the metal plate, so that the resin film is deformed even under light contact, and excellent -11 - (8) (8) 200806468 can be obtained. Electrical conductivity. In order to effectively exhibit the deformation energy-promoting action of the resin film controlled by PpIt, the excellent conductivity is ensured, and PPIt is made 70 or more. When PPIt is less than 70, excellent conductivity cannot be obtained as shown in the examples described later. The larger the PPIt, the better. Thus, the number of peak portions that can become the conduction point can be increased. Further, when the number of peak portions is increased, the local pressure applied to the peak portion is increased, and as a result, the entire resin film is easily deformed, so that deformation under light contact can be promoted. The PMt is, for example, preferably 100 or more, more preferably 120 or more, and most preferably 150 or more. In addition, the upper limit of the PPIt is not particularly limited. However, when the PPIT is too large, unevenness of the resin film occurs, and it is difficult to make the adhesion amount uniform, and the appearance is unstable. In view of these, it is preferably set to be approximately 500 or less. More preferably 400 or less, and most preferably 3 〇 0 or less. The control method of PPIt will be described in detail later. Examples of the base resin constituting the resin film include a polyester resin, a propylene resin, a urethane resin, a polyolefin resin, a fluorine resin, a fluorene resin, and a mixture of these resins or a modified resin. . Further, the resin-coated metal sheet of the present invention is mainly used for a frame of an electronic device, and it is preferably a polyester resin or a modified poly group in consideration of characteristics such as bending workability, film adhesion, and corrosion resistance. An ester resin (for example, a resin modified by adding an epoxy resin to an unsaturated polyester resin). The resin film may further contain a bridging agent in addition to the base resin. The type of the bridging agent is not particularly limited as long as it is generally used in the resin-coated metal sheet. For example, a melamine-based compound, an isocyanide-12-200806468 (9) acid-based compound, and the like can be given. These can be used alone or in combination. The content (total amount) of the bridging agent is preferably in the range of approximately 5 to 30% by mass. (2) Control of the glass transition point (Tg) of the resin film According to the present invention, the resin is controlled as in the above (1) The shape of the film (PP It ) can promote the deformation of the resin film, and as a result, the conductivity can be improved. However, for the purpose of further improving the properties, it is preferable to control the glass transition point (Tg) of the resin film to 60° C. or less. In the control of the Tg of the resin film, particularly when the PPIt of the resin film is in the range of about 70 to 250, the deformation promoting effect of the resin film can be further improved (see the examples described later). On the other hand, when the PPIt of the resin film is extremely large, for example, at about 3 50 or more, the deformation of the resin film can be maximized regardless of the Tg of the resin film, so that the Tg of the resin film exceeds 60°. C, also • The desired conductivity can be obtained. Here, the Tg of the resin film means the Tg of the entire resin film. As described in detail later, in the resin film, in addition to the base resin and the bridging agent constituting the coating film, a known additive such as a rust preventive, a matting agent, or a pigment may be contained, and the Tg is not affected by the inorganic agent such as a rust preventive agent. The influence of the compound is such that the Tg of the resin film is substantially determined by the type and amount of the base resin and the bridging agent to be used. Therefore, in order to control the Tg of the resin film, the blending amount may be appropriately adjusted depending on the type of the base resin and the bridging agent as the main component. Resin skin -13- 200806468 (10) The Tg of the film is largely governed by the Tg of the base resin. Further, the content of the base resin is more than that of the bridging agent, and the Tg of the resin film tends to decrease. On the contrary, the content of the base resin is less than that of the bridging agent, and the tendency to rise is increased. In consideration of the above aspects, in order to control the Tg of the resin film, first, a base resin having a Tg close to the target Tg is selected, and the base resin and the bridging agent are blended to control the Tg of the resin film within a predetermined range. Just fine. In the following, as a representative example of the resin film used in the present invention, a polyester resin is used as the base resin, and a melamine resin is used as the bridging agent, and the method for controlling the Tg is specifically described. Description. Typical examples of the polyester-based resin include the Vylon series manufactured by Toyobo Co., Ltd. Specifically, it can be exemplified by Vylon 103 (Tg: about 47 ° C) and Vylon 2 00 (Tg: about 67 〇 C).

Vylon 220 (Tg: about 53 ° C), Vylon 240 (Tg: about 60 # °C), Vylon 245 (Tg: about 60 ° C), Vylon 270 (Tg: about 67 ° C), Vylon 280 (Tg: About 6 8 ° C), Vylon 290 (Tg: about 7 2 ° C), Vylon 2 96 (Tg: about 71 ° C), Vylon 300 (Tg: about 7 ° C), Vylon 500 (Tg: about 4 °) C),

Vylon 5 30 (Tg ·· about 5°C), Vylon 5 5 0 (Tg: about -15 °C), Vylon 5 60 (Tg: about 7°C), Vylon 600 (Tg: about 4 7〇C) , Vylon 630 (Tg: about 7 °C), Vylon 650 (Tg: about l〇 °C), Vylon GK110 (Tg: about 50 °C) > Vylon

GK130 (Tg: about 15 ° C), Vylon GK140 (Tg: about 20 ° C • 14- (11) 200806468 ), Vylon GK1 50 ( Tg : about 2 01 : ) , Vylon GK1 8 0 ( Tg : about 0 ° C), Vylon GK190 (Tg: approx. 1 1 °C), Vylon

GK250 (Tg: about 60〇C), Vylon GK3 3 0 (Tg: about 16°C), Vylon GK590 (Tg: about 15 °C), Vylon GK640 (Tg: about 79°C), Vylon GK680 (Tg: About 10 °C), Vylon GK780 (Tg: about 36 °C), Vylon GK 8 1 0 (T g: about 4 61: ), Vylon GK8 80 (Tg: about 84 ° C), Vylon GK890 (Tg

: approximately 17 ° C), Vylon BX1001 (Tg: approximately -18 ° C), etc. These Tg are the temperatures stated in the catalog. Examples of the melamine-based resin include SUMIMAL M-40ST manufactured by Sumitomo Chemical Co., Ltd., and the like. In the examples described later, in order to control the Tg of the resin film to a predetermined enthalpy (10 ° C, 25 ° C, 40 ° C, 60 ° C, 75 ° C), the polyester resin is selected from the polyester resin. A polyester resin having a Tg close to the predetermined 値Tg is blended with a melamine resin. Specifically, 'as shown in Table 1 below. -15- (12) 200806468 [Table 1] Tg (°C) of the resin film Base resin A bridging agent B Mixing ratio (mass ratio) Type Tg (°C) 10 Vylon 650 10 manufactured by Toyobo Co., Ltd. Sumitomo SIIMALM- 40ST A manufactured by Chemical Co., Ltd.: B=100: 20 25 Vylon GK140, manufactured by Toyobo Co., Ltd. 20 40 Vylon GK780, manufactured by Toyobo Co., Ltd. 60 60 Vylon 245 60 75, manufactured by Toyobo Co., Ltd. Vylon 290 72, manufactured by Kasei Co., Ltd.

The Tg of the resin film can be measured by a conventional method using DSC (differential scanning calorimeter). The Tg of the resin film is preferably as low as possible from the viewpoint of improving the conductivity of the resin film, and for example, it is preferably at most 5 5 ° C, more preferably at most 50 ° C, and most preferably at 45 ° C. the following. In addition, the lower limit of Tg is not particularly limited from the viewpoint of conductivity, and when Tg is low, characteristics other than electromagnetic shielding properties required for the casing of the electronic device (for example, tamper resistance and uranium resistance) are lowered. Preferably, it is l〇°C or more, more preferably 15°C or more, and most preferably 20°C or more. (Type of metal plate) In order to obtain a resin-coated metal plate having excellent electromagnetic shielding properties, the shape of the resin film is controlled as described above, or it is optimal to further control the Tg of the resin film-16-(13)(13)200806468 However, the electromagnetic wave absorptivity can be improved by controlling the type of the metal plate as follows, and as a result, the electromagnetic wave shielding property can be further improved. In addition, as described below, by using a metal plate having a large hardness (the deformation energy of the metal plate is small), the deformation of the resin film can be promoted, and the conductivity tends to be improved. Therefore, it is considered that good electromagnetic wave shielding properties can be obtained. As a metal plate used in the present invention, a plated steel sheet (zinc-iron group alloy plating) which is preferably alloyed with zinc and an iron group element (Fe, Co, Ni) is preferable to the widely used electrogalvanized steel sheet. Covered steel plate). Examples of the alloy-plated steel sheet of the zinc-iron group element include an alloy-plated steel sheet of Zn and Fe, an alloy-plated steel sheet of Zn and Ni, and an alloy-plated steel sheet of Zn and Co. From the viewpoint of ensuring electromagnetic wave absorptivity, the Fe, Ni, and Co contents are preferably controlled to be substantially in the range of 5 to 20% by mass. Further, the method of plating is not particularly limited, and can be obtained by any of a hot-dip plating method and an electroplating method. Further, the detailed plating conditions of the hot-dip plating method and the plating method are not particularly limited, and a method generally used for alloying can be employed. When the electromagnetic wave absorptivity is considered, the amount of adhesion of the plating is preferably as small as possible, and for example, it is preferably 50 g/m 2 or less, more preferably 40 g/m 2 or less, still more preferably 35 g/m 2 or less, and most preferably 3 〇 mg / Below m2. The lower limit of the amount of plating adhesion is not particularly limited, but is preferably 5 g / m 2 , and most preferably 1 〇 g / m 2 , in view of resistance to enthalpy and the like. Further, in consideration of cost and the like, it is preferable to use an alloyed hot-dip galvanized steel sheet which is inexpensive and easy to manufacture (a steel sheet which is alloyed by Zn and Fe -17-(14) 200806468 by a hot-dip coating method). As described above, in the present invention, an alloy steel sheet is preferably used as the metal sheet, and a pure zinc plated steel sheet or a cold-rolled steel sheet having a plating adhesion amount of about or less may be used. This is because these have excellent electromagnetic wave absorbing effects and can realize desired conductive embodiments as will be described later. Further, as described above, by using a steel sheet which is not alloyed, it is possible to avoid problems in use of the alloyed steel sheet (cracking or peeling of cracks or the like which occur during bending processing). For example, if a cold-rolled steel sheet which is not plated is used, it can be processed for strict use. In particular, it has been found that the cold-rolled steel sheet has superior wave absorbability as compared with the alloyed steel sheet (see the examples described later). However, the difference in cold-rolled steel sheets, if considering the frame used for electronic equipment, is a comprehensive feature. Therefore, it is preferable to use alloyed plated steel sheets as compared with cold-rolled steel sheets. On the other hand, if pure zinc-plated steel sheets are used. It can be used in applications that are severe and require corrosion resistance. In order to effectively exhibit the contact-resistant adhesion amount, it is preferably about 3 g/m2 or more, more preferably 6 g/m2, and in consideration of electromagnetic wave absorptivity, the upper limit of the plating adhesion amount is 15 g/m2, more preferably 12 g/ M2 is optimally 10 g/m2. The necessary conditions and types for characterizing the resin film of the present invention have been described above. The thickness (average thickness) of the resin film is preferably in the range of approximately 3. Ομηη. If the thickness is outside the above range, the characteristics of the electromagnetic shielding of the electric frame are not the same as those of the electromagnetic shielding (bending plus plating of 15 g/m2 steel plate (see, for example, for electromagnetic observation) Corrosion resistance evaluation is lower than workability, plating. It is also best for metal plate 0· 1~ sub-workability, -18 - (15) 200806468 According to the so-called, etc., there are also 0 · 2 μιη The frame of the mirror observation device is because of course, it can also contain, etc.) additives, powders, powders, and the like. The ferrite metal powder (35% or more of the alloy) has a decreased film adhesion, corrosion resistance, and the like. The thickness of the base material resin and the metal plate for the thickness of the resin film is different from the roughness of the metal plate, and it is difficult to uniquely determine the thickness of the resin film. More preferably, it is approximately 2.0 μm or less, more preferably 0.3 μm or more and 1.5 μm or less. The thickness of the film can be measured by the specific gravity according to the weight of the film, or the cross section of the resin film can be measured (SEM observation). The φ resin film may be formed on at least the back surface of the metal plate (the inside of the non-outer side (outside gas side) as viewed from the electron body). The electromagnetic wave shielding property may cause problems on the inner side of the electronic device member or may be formed on the front and back sides of the metal plate. In addition to the base resin and the bridging agent, the resin film may have a known additive (for example, a rust preventive, a matting agent, or a pigment resin film may further contain a magnetic powder (electromagnetic wave absorption, whereby electromagnetic wave shielding can be further improved) Examples of the magnetic soft magnetic ferrite powder and the magnetic metal are soft magnetic ferrite powders, for example, soft magnetic Ni-Zn powder, Mn-Zii ferrite powder, etc. For example, permalloy (an alloy having a Ni content in a Ni-Fe alloy) and an iron alloy (Sendust) (Si-Al-Fe system) may be used alone or in combination. The content of the magnetic powder (total amount) is the most Preferably, it is in the range of 20 to 60% by mass. When the content is less than 20% by mass, the above effects cannot be effectively exerted. On the other hand, when it exceeds 60% by mass, the electronic device member is coated with the tree 200806468 (16). The properties required for the steel sheet (bending workability, film adhesion, and corrosion resistance) tend to deteriorate. The content of the magnetic powder depends, for example, on the type and shape of the magnetic powder used. The thickness of the resin film is also different, and it is difficult to determine uniquely. However, it is more preferably about 25% by mass or more and 5% by mass or less, and most preferably 30% by mass or more and 45% by mass or less. When the average particle diameter is 15 μm or less, it is preferable to remove a powder having a large particle diameter (for example, 20 μm or more) as much as possible. Thereby, formation of the Φ magnetic coating film is easy, and workability and uranium resistance can be suppressed from being lowered. Here, the average particle diameter of the magnetic powder is a particle size distribution of the magnetic powder particles after classification by a general particle size distribution meter, and the particle size of the 値50% from the small particle diameter side calculated based on the measurement result. (D50) The particle size distribution is measured by a diffraction pattern of the diffraction and scattering of the magnetic powder particles, and the particle size distribution meter is exemplified by Microtrac 9220FRA or Microtrac HRA # manufactured by Nikkiso Co., Ltd. In the case of the magnetic powder which satisfies the above-mentioned optimum average particle diameter, a commercially available product can also be used. For example, Ni-Zn-based soft magnetic ferrite can be cited [Toda Industry BSN-125, average particle size 13·0μιη], permalloy (78% Ni) [SFR-PC78, Atomize Processing Co., Ltd., average particle size 5·7μπι], permalloy (45% Ni) [SFR-PB45 manufactured by Atomize Processing Co., Ltd., average particle diameter 5.8 μm], iron-stained aluminum alloy [SFR_FeSiAl (84.5-10-5.5) manufactured by Atomize Processing Co., Ltd., average particle diameter 6.9 μm], etc. 20- (17) 200806468 In order to further improve the electromagnetic shielding properties of the resin-coated metal sheet, a conductivity imparting agent may be added to the resin film. Examples of the conductivity imparting agent include metal monomers such as Ag, Zn, Fe, Ni, and Cu, and metal compounds such as FeP. Among them, Ni is particularly preferred. Further, the shape thereof is not particularly limited, but in order to obtain more excellent conductivity, for example, a scaly structure is recommended. The content of the conductivity imparting agent contained in the resin film is preferably approximately 20 # to 40% by mass. Strictly speaking, the amount of addition can be appropriately adjusted depending on the kind of the magnetic powder to be used and the like. For example, when a soft magnetic ferrite powder is used as the magnetic powder, it is preferred to add a conductivity imparting agent as much as possible (for example, 25% by mass or more). Further, when a magnetic metal powder is used as the magnetic powder, it is preferred to add a conductivity imparting agent as little as possible (for example, 30% by mass or less). On the other hand, when the conductivity imparting agent is considered to have an adverse effect on the workability or the like as in the case of the magnetic powder, the total content of the conductive property imparting agent and the magnetic powder contained in the magnetic coating film is preferably about 60. Within the range of mass % or less. The metal plate may be subjected to a surface treatment (substrate treatment) such as chromate treatment or phosphate treatment for the purpose of improving the contact resistance and improving the adhesion to the resin film. Alternatively, a metal plate not subjected to chromate treatment may be used in consideration of environmental pollution or the like, and a metal plate subjected to any substrate treatment is included in the scope of the present invention. When performing the above substrate treatment, the adhesion amount of the substrate treatment is preferably about 300 mg/m2 or less, and most preferably 2 〇〇mg/m2 or less - 21 - (18) (18) 200806468 in consideration of conductivity and the like. More preferably, it is 150 mg/m2 or less, and most preferably i〇〇mg/m2 or less. Further, the method of non-chromate treatment is not particularly limited, and a known substrate treatment which is generally used may be carried out. Specifically, it is recommended to treat the substrate alone or in combination with a phosphate-based or cerium oxide-based "titanium system" or a pin system. Further, in general, when the non-base acid salt treatment is performed, the corrosion resistance is lowered. Therefore, for the purpose of improving the corrosion resistance, a rust preventive agent can be used in the coating film or the substrate treatment. Examples of the rust preventive agent include a cerium oxide compound, a phosphate compound, a phosphite compound, a polyphosphate compound, a sulfur organic compound, a benzotriazole, a tannic acid, and a molybdate compound. A tungstate compound, a vanadium compound, a decane coupling agent, etc. can be used individually or in combination. Particularly preferred is a combination of a cerium oxide-based compound (for example, calcium ion-exchanged cerium oxide) and a phosphate-based compound, a phosphite-based compound, or a polyphosphate-based compound (for example, aluminum tripolyphosphate). A cerium oxide compound (a phosphate compound, a phosphite compound, or a polyphosphate compound) is used in combination with a mass ratio of 0.5: 9.5 to 9.5: 0.5 (more preferably 1: 9 to 9: 1 ). ). By controlling in this range, both desired corrosion resistance and workability can be ensured. By the use of the above rust preventive agent, the corrosion resistance of the non-chromate-treated metal sheet can be ensured, but on the contrary, the workability is lowered due to the addition of the rust preventive agent. For this reason, as a component for forming a coating film, a polyester resin in which an epoxy-modified polyester resin and/or a phenol derivative is introduced into a skeleton, and a bridging agent (preferably an isocyanate resin and/or Or a melamine-based resin, preferably used in combination). Among them, an epoxy-modified polyester resin and/or a phenol derivative are introduced into a polyester resin of a bone-22-(19) (19)200806468 shelf (for example, a polyester resin in which bisphenol A is introduced into a skeleton, etc.) ) It is excellent in corrosion resistance and coating film adhesion compared with a polyester resin. On the other hand, the 'isocyanate bridging agent has an effect of improving the workability (refers to an effect of improving the appearance after processing, and is evaluated in the examples described later by the number of cracks in the adhesion bending test). Even if a rust inhibitor is added, excellent workability can be ensured. In addition, the melamine bridging agent has excellent corrosion resistance. Therefore, in the present invention, by using in combination with the above-mentioned rust preventive agent, very good corrosion resistance can be obtained. These isocyanate bridging agents and melamine-based bridging agents can be used singly, but when used in combination, the workability and the tamper resistance of the non-chromated metal sheets can be further improved. Specifically, it is recommended to contain the melamine-based resin in a ratio of 5 to 80 parts by mass with respect to the isocyanate-based resin 1 〇〇 mass portion. When the melamine resin is less than 5 parts by mass, the desired corrosion resistance cannot be obtained. On the other hand, when the melamine resin exceeds 80 parts by mass, the effect of the addition of the isocyanate resin cannot be satisfactorily exhibited, and the effect cannot be obtained. The desired processability is enhanced. More preferably, it is 10 parts by mass or more and 40 parts by mass or less, more preferably 15 parts by mass or more and 30 parts by mass or less, based on 100 parts by mass of the isocyanate-based resin. The resin-coated metal sheet of the present invention is coated with a resin film containing the above various additives on the surface of the metal plate (including the portion subjected to the substrate treatment described above), but imparts tamper resistance and fingerprint resistance as needed. For the purpose, a two-layer film structure in which another resin film is applied may be formed on the surface of the resin film. -23- (20) (20) 200806468 Next, a method of producing the resin-coated metal sheet of the present invention will be described. In the resin-coated metal sheet of the present invention, a coating material containing various additives as needed, in addition to the base resin and the bridging agent, is applied to the surface of the metal plate by a known coating method, and is obtained by baking. Here, in order to control the PPIt of the resin film within the scope of the present invention (70 or more), it is preferable to control the surface roughness of the raw material sheet (metal plate) as follows (the arithmetic mean roughness prescribed by JIS B 060 1 (1 994)) The degree Ra, hereinafter referred to as Ra) and the method of forming the resin film (viscosity and solid concentration of the coating, the burning condition of the coating, etc.). First, the Ra of the metal plate as the raw material plate is preferably controlled to be in the range of 0.8 to 1·6 μm. For example, when the steel sheet is used as the raw material sheet, if the Ra of the tempering roll is approximately controlled within the range of 0.6 to 3.2 μm, and the rolling ratio during rolling is approximately controlled within the range of 0.3 to 2.5%, it is possible to The Ra of the metal plate is controlled within the above range. In the temper rolling process, the surface shape of the roll for temper rolling is transferred to the plated raw material plate at a high transfer rate, but as in the present invention, a very thin resin film is applied to the plating. In the case of the raw material plate, the surface shape of the plated resin film is considered to substantially reflect the surface shape of the raw material plate, and therefore, Ra of the metal plate as the raw material plate is appropriately controlled. The rolling ratio is determined based on the Ra of the tempering roll in an appropriate range. The Ra of the tempering roll can be appropriately adjusted by, for example, a known processing method such as a spray passivation process, a discharge passivation process, or a laser passivation process. For example, when using a spray-passivation process, the surface roughness of the tempering roll can be adjusted using a grinding material having a particle size adjusted. The viscosity of the coating is preferably in the range of 10 -24- (21) (21)200806468 seconds to 40 seconds, preferably in the range of 1 5 to 30 seconds. . Here, it means that the shorter the time, the lower the viscosity. For example, when the viscosity of the coating material used is less than 10 seconds in Ford Cup No. 4, the paint easily penetrates into the valley portion (concave portion) of the metal sheet, and therefore the PPIt of the resin film tends to decrease. On the other hand, when the viscosity of the coating material used is more than 40 seconds in Ford Cup No. 4, the surface roughness (the shape of the unevenness) of the metal sheet greatly affects the formation of the resin film, under light contact. Conductivity may become unstable. The solid concentration of the coating material is appropriately adjusted to be easy to apply depending on the viscosity and coating conditions of the coating material to be used, but is preferably in the range of preferably 2 to 20% by mass, more preferably 4 to 16% by mass. The optimum is in the range of 6 to 12% by mass. The burnt-bonding condition is, for example, a change in the degree of the valley portion (concave portion) which flows into the metal sheet according to the type of the solvent used for the dilution of the paint, and the like, and it is preferable to finish the sticking in about one minute. The coating method is not particularly limited, and examples thereof include a cleaning surface, and if necessary, a roll coating method, a spray method, or a spray method on a surface of a long metal strip on which a pre-coating treatment (for example, a phosphate treatment, a chromate treatment, or the like) is performed. A method of applying a coating such as a curtain coating method to dry it in a hot air drying oven. The roll coating method is practically preferable in consideration of uniformity of film thickness and processing cost, coating efficiency, and the like. As an electronic device member to which the resin-coated metal sheet of the present invention is applied, for example, an electronic device member in which a heat generating body is built in an enclosed space, the electronic device member further including all or a part of an outer wall thereof by the above-described electronic device member -25-200806468 ( twenty two)

An electronic device component constructed of an applicator. As the above electronic device component, oh! J holds information recording products such as CD, LD, DVD, CD-ROM, CD-RAM, PDP, LCD, etc., personal computers, car navigation systems, car AV, etc. 电气 Electrical, electronic, communication related products, projectors, televisions, Video recorders such as AV equipment such as game machines, copying equipment such as photocopiers and printers, power box covers such as air conditioner outdoor units, control box covers, vending machines, refrigerators, etc. [Embodiment] Hereinafter, examples are more specific. The present invention is not limited by the following examples, and can be appropriately modified and implemented within the scope of the present invention. These are all included in the technical scope of the present invention. Plate) The surface roughness (Ra) of the tempering roll was changed within the range of 0.6 to 3.2 μm using various metal plates (the plate thickness was 0.6 mm) shown below, and the rolling ratio during rolling was made 〇 3 to 1. 5 % variation within the range, whereby the surface roughness (Ra) of the metal sheet is varied within the range of 0.56 to 1.35 μm. By changing the grain size of the sand within the range of #50 to #70 , use adjusted granularity In the following description, "%" is not particularly limited to mass%. In addition, the plated steel sheet (EG, GI, GA, ZN) is changed by the spray-cutting passivation process. , ZF ) All carried out -26- (23) 200806468 two-sided plating. EG (1): electro-galvanized steel sheet (single-side plating adhesion 20g / m2, Ra: 0.76pm) EG ( 2 ): electro-galvanized steel sheet ( Single-sided plating adhesion amount 15g/m2, Ra: 0·78μπι) EG (3): electro-galvanized steel sheet (single-side plating adhesion amount 12g/m2, Ra: 0·75μπι) φ EG ( 4 ): electrogalvanized steel sheet (single-side plating adhesion amount: 9g/m2, Ra: 0.80μιη) EG (5): electro-galvanized steel sheet (single-side plating adhesion amount: 6g/m2, Ra: 0·76μηι) EG (6): electrogalvanized steel sheet ( Single-sided plating adhesion amount 3g/m2, Ra: 0.77μπ〇GI: hot-dip galvanized steel sheet (single-side plating adhesion amount 60g/m2, Ra: 0·56μηι) # CR : cold-rolled steel sheet (Ra: 0·86μπι GA (1): Alloyed hot-dip galvanized steel sheet (single-side plating adhesion 40g/m2, Fe: 10%, Ra: 1. 3 4 μιη) GA ( 2 ): alloyed hot-dip galvanized steel sheet (single-sided Plating adhesion amount 40g/m2, Fe: 10%, Ra: 0.8 2 μ m ) GA ( 3): Alloyed hot-dip galvanized steel sheet (single-sided plating adhesion amount 35g/m2, Fe: 10%, Ra: -27- (24)200806468

1 . 3 2 μιη ) GA ( 4 ): Alloyed hot-dip galvanized steel sheet (single-side plating adhesion amount 30 g/m 2 , Fe : 10%, 1. 3 5 μιη ) GA ( 5 ): alloyed hot-dip galvanized steel sheet (Single-side plating adhesion amount 25g/m2, Fe: 1 〇%, 1.30 μιη) φ ΖΝ : Zn-Ni alloyed plated steel sheet (single-side plating adhesion amount 20g/m2, Ni·: 10%, 0.8 3 μιη ) ZF : Ζ η - F e alloyed plated steel sheet (single-side plating adhesion amount: 20g/m2, Fe: 10%, 0.81 μιη) (Preparation of resin film) # Prepare various materials containing the components shown in Table 1. The coating was applied to a metal bar with a bar coat. As the diluent, a mixed solvent of dioxanone (1:1) was used. The thickness of the resin film was varied in the range of 0.3 to 2.4 μm by diluting the solid concentration of the coating material and the number of bars used in the coating of the strip coating film. After coating the above coating, the passing time of the hot air drying oven was carried out under the following conditions (in-furnace time): 50 seconds. The arrival temperature of the hot air drying oven was 2 3 0 °C.

Ra :

Ra :

Ra ··

Ra : Branches for the change of toluene -28- (25) (25)200806468 (Evaluation of resin film) (Measurement of T g) The Tg of the resin film is based on a differential scanning calorimeter according to JIS K 7121 (product name: Thermo Plus DSC8230, The measurement was carried out by Rigaku Co., Ltd. Specifically, the resin film obtained from the resin-coated metal sheet produced as described above was placed in a differential scanning calorimeter, cooled to -100 ° C, and stabilized, and then heated to 180 ° at a rate of 2 (TC / min). c, and then the glass transition temperature (Tg) is obtained from the obtained DSC curve. (Measurement of PPIt) For PPIt, a resin film is standardized in the PPI of SAE J91 1-JUN86 (1 98 6 ) in the United States. The average thickness (μιη) was taken as the reference height, and the PPIt of the resin-coated metal plate was calculated. The measurement conditions were cutoff 値: 〇·8 mm, and the tip end radius R: 2 μιη (the stylus portion was regarded as a ball), and the measurement was performed. Length: 2 5 · 4 mm. Actually, considering the measurement error (±4 mm), cross-contact the needle in the range of 26.2 mm. In addition, the measurement position is arbitrarily selected from 1 position and the average 値 is taken as PPIt. Five positions are selected in total in the same direction, and five positions are selected in total in the direction perpendicular to the direction. The average thickness of the resin film is obtained by the method described below. First, the weight is 1 to 10% by weight in the paint. Ratio of strontium oxide added Si〇2) The amount of Si adhesion was measured by a fluorescent X-ray analysis method as a marker. When measuring the amount of attachment of Si, a calibration curve indicating the relationship between the amount of § i and the intensity of fluorescent X-rays was prepared in advance. Based on the calibration curve, the amount of adhesion of Μ -29-(26) 200806468 was measured. Then, as described above, the weight of the resin film was calculated from the measured amount of Si deposition, and the average thickness t was obtained. Μηι ) The specific conversion method is as follows.

The average thickness of the resin film ί(μπι) = {A/(BxCxD) } xlOOO φ where

Si adhesion amount (mg/m2) B = 2 8/ 6 0 (Si/Si02) c Weight ratio of diSi〇2 D = specific gravity of resin film (g/cm3) Average of resin film obtained as described above The thickness (t) was used as a reference level for each of the positive and negative (peak enthalpy level), and the number of peaks and valleys exceeding the film thickness t per inch was measured to determine PP It. (Evaluation of Conductivity) _ The resistance of the surface of the resin-coated metal plate was measured as follows using a tester [manufactured by Casuyama Co., Ltd. CX-250]. As shown in FIG. 5, the terminal is held at 45. At the same time, it was slid on the surface of the resin-coated metal plate at an average speed of 30 mm/sec (measurement length 100 mm). The pressure at the time of measurement was carried out under light contact of only the terminal weight (7 g). The measurement enthalpy was read after the measurement of enthalpy (resistance enthalpy) was completed for 1 second or more from the start of the measurement. -30- (27) (27)200806468 The measurement position was changed to perform the same operation as above for a total of 20 times, and the average 値 was used as the resistance 値. In the present embodiment, the evaluation of the electric resistance 値 obtained as described above was lower than 〇〇 Ω, and the electric conductivity was excellent (pass), and the evaluation of the electric resistance 値 of 100 Ω or more was poor in conductivity (failed). The larger the resistance, the worse the conductivity. In addition, in the evaluation method of the present embodiment, the pressure at the time of resistance 値 measurement is in the range of 10 to 12 g/mm 2 and the conductivity under light contact is evaluated, and the above-mentioned Japanese Patent Laid-Open Publication No. 2004-156081, Japan The conductivity evaluation methods described in JP-A-2005-277876 are different. In these documents, Loreta AP or GP manufactured by Mitsubishi Petrochemical Co., Ltd. was used as a surface resistance tester, and ASP or LSP probe was used as the probe probe conductivity, and the pressure of the probe at the time of measurement was calculated. It is 33 to 460 g/mm 2 and is very high compared to this embodiment. (Evaluation of electromagnetic wave absorptivity) Fig. 2 is a view for explaining a method of evaluating electromagnetic wave absorptivity of a resin-coated metal plate. As shown in FIG. 2, in the rectangular parallelepiped casing 1, a high-frequency loop antenna 5 is provided, and a magnetic field is combined. The high frequency loop antenna 5 is connected to one end of the coaxial cable 6 via a connector (not shown), and the other end of the coaxial cable 6 is connected to the network analyzer 7. In the network analyzer 7, an electromagnetic wave is generated while sweeping the frequency, and is input into the casing 1 via the coaxial cable 6 and the high-frequency loop antenna 5 (high-frequency input wave: arrow B). In the resonance frequency of the casing 1, since the input electromagnetic wave is accumulated, it is possible to observe the characteristic of the decrease in the amount of reflection (see Fig. 3). Then, the high-frequency reflected wave of -31 - 200806468 (28) is indicated by the arrow C as the observation 値 input network analyzer 7 (high-frequency reflected wave: arrow C). At this time, when Q値 obtained by the following formula (2) in the measurement frame 1 is measured, the amount of energy accumulated in the casing 1 is known. Further, Q 求出 obtained from the following formula (2) is a 算出 calculated from the frequency difference Af obtained by the condition satisfied by the admittance orbit and the resonance frequency fr (for example, Nakajima will be lighted "Senbei Electrotechnical Series 3 Microwave Engineering - Foundation and Principles issued by Moribe Publishing Co., Ltd. _ , pp. 159 ~ 163.) Q 値 = fr / Af .... (2) This means that the smaller the Q 求出 from the above equation (2) The smaller the energy accumulated in the body 1. Therefore, the smaller the Q値, the smaller the electromagnetic field level reflected from the frame i to the inside. The situation pattern at this time is not shown in Fig. 4, which shows the so-called Ez ^ = 0 The electromagnetic field distribution of the resonance mode of the lowest frequency of TE0 1 1 , where E is a local frequency magnetic field and F is a high frequency electric field. The above Ez is the meaning of the electric field strength in the z direction, and TEou represents the electromagnetic field distribution of the resonance mode. Attitude. The TE means that the wave advances in the z direction, and there is an electric field in the lateral direction. The additional word t〇ll” indicates that there is an electric field intensity distribution in the y and Z directions with respect to the X, y, and z directions, in the X direction. The electric field intensity distribution does not change (for example, 'refer to pages 141 to 144 of the above-mentioned documents). In addition, the electromagnetic field distribution shown in FIG. 4 is represented by the following formula.

Hz ^ H011 · cos ( ky · y ) · sin ( kz · z) -32» (29) 200806468

Hy= ( -kz · ky/kc2) · Η〇ιι· sin(ky· y) · cos ( kz • z )

Ex=(-jcopky/kc2) · H 〇 11 · s i n ( k y · y ) · sin ( kz · z ) Here, ky=^K/b, kz^w/c, and kc=ky. b, c is the length in the y and z directions of the rectangular parallelepiped (frame 1) of Fig. 4, j is an imaginary number, ω is the frequency, and μ is the magnetic permeability of the air... φ The inventors have made the sample steel plate The ratio of the inner surface is increased to around 100% (i.e., until the entire surface of the inner surface of the frame). Fig. 6 is an explanatory view showing a SUS frame (frame) constituting the frame, Fig. 6(a) is a plan view, Fig. 6(b) is a front view, and Fig. 6(c) is a left side view. Further, the frame is configured to be vertically symmetrical, so that the bottom view, the rear view, and the right view are respectively a top view (Fig. 6 (a)), a main view (Fig. 6 (b)), and a left view (Fig. 6 (c) ) Same performance. On the frame shown in Fig. 6, the sample steel plate and the SUS plate shown in Figs. 7 and 8 are attached (mounting screws) to form a frame (240 x 1 80 x 90 mm). Further, Fig. 7(a) is a sample steel plate (two pieces) disposed on the front and back portions of the frame, and Fig. 7(b) is a sample steel plate (two pieces) disposed on the left and right side surface portions of the frame, Fig. 8 (a) is a SUS plate disposed on the upper portion, and (b) is a SUS plate disposed on the bottom surface portion. According to the configuration described above, if the frame is produced, the sample steel sheet can occupy the inner surface up to a ratio of approximately 100%. In addition, the mounting screws have a pitch of 20 to 40 mm, which reduces the contact resistance, and therefore requires a plurality of stopper screws. The set screw can improve the Q値 measurement by managing the torque. -33- (30) 200806468 Present. Using this frame, Q 値 (the above Fig. 2) was measured, and electromagnetic wave absorptivity was calculated from the following formula. Electromagnetic wave absorptivity (dB) of the sample steel sheet = l〇xl〇g1G([EG)/[A)) where [EG]: Q値[A] of the electrogalvanized steel sheet to be the substrate: Q of the sample steel sheet The 値 evaluation is that the higher the enthalpy (dB) calculated by the above method, the more excellent the electromagnetic wave absorptivity. In the present embodiment, the evaluation of enthalpy calculated as described above above 3.0 dB is excellent in electromagnetic wave absorptivity (pass), and the evaluation below 3.0 dB is poor in electromagnetic wave absorptivity (failed). The evaluation was as described above, and the larger the electromagnetic enthalpy, the more excellent the electromagnetic wave absorptivity. These results are collectively recorded in Tables 2 and 3. In addition, in Tables 2 and 3, a comprehensive evaluation column is provided, and a comprehensive evaluation is performed based on the following criteria. The comprehensive evaluation of ◎ or 〇 is "an example of the present invention". ◎: Both conductivity and electromagnetic wave absorption are acceptable. 导电 导电 导电 导电 导电 导电 导电 导电 导电 导电 导电 导电 : : : : : : : : : : : : : : : : : : : : : : : X X X X X X X X X X X X X X X X 2】

No Raw material sheet resin film guide, comprehensive evaluation of 电磁 electromagnetic wave absorption Tg (°C) Average thickness (μπι) PPIt resistance 値 (Ω) Evaluation 値 dB) Evaluation 1 0.3 351 8 〇 3.29 〇 ◎ 2 0.5 300 15 〇 3.31 〇 ◎ 3 0.7 242 21 〇 3.25 〇 ◎ 4 40 1.0 184 28 〇 3.28 〇 ◎ 5 1.2 146 32 〇 3.30 〇 ◎ 6 1.6 107 60 〇 3.29 〇 ◎ 7 1.9 80 80 〇 3.27 〇 ◎ S GA 2.4 51 100 or more X 3.22 〇X 9 (1) 10 1.9 78 57 〇 3.27 〇 ◎ 10 25 1.9 82 65 〇 3.29 〇 ◎ 11 60 1.9 81 86 〇 3.30 〇 ◎ 12 75 1.9 83 97 〇 3.28 〇 ◎ 13 10 1.0 180 8 〇 3.31 〇 ◎ 14 25 1.0 182 16 〇 3.27 〇 ◎ 15 60 1.0 179 34 〇 3.29 〇 ◎ 16 75 1.0 185 50 〇 3.24 〇 ◎ 17 0.3 262 21 〇 3.31 〇 ◎ 18 0.5 190 32 〇 3.26 〇 ◎ 19 40 0.7 138 40 〇 3.24 〇◎ 20 0.9 80 79 〇3.27 〇◎ 21 1.0 61 100 or more X 3.30 〇X 22 GA 10 0.9 77 59 〇3.28 〇◎ 23 25 0.9 78 67 〇3.29 〇◎ 24 (2) 60 0.9 80 85 〇3.25 〇 ◎ 25 75 0.9 78 93 3.24 〇 ◎ 26 10 0.7 135 18 〇 3.26 〇 ◎ 27 25 0.7 140 27 〇 3.28 〇 ◎ 28 60 0.7 145 50 〇 3.31 〇 ◎ 29 75 0.7 141 71 〇 3.21 〇 ◎ 30 GA (3) 40 0.6 280 17 〇 3.45 〇 ◎ 31 GA(4) 40 0.6 310 13 〇3.65 〇◎ 32 〇A(5) 40 0.6 298 16 〇3.86 〇◎ -35- (32)200806468

[Table 3] Comprehensive evaluation of conductive electromagnetic wave absorptivity of resin film No T2 (°C) Average thickness (μιη) PPIt Resistance 値 (Ω) Evaluation proud dB) Evaluation 33 0.6 147 39 〇0.01 X 〇34 40 0.9 120 60 〇-0.02 X 〇35 1.0 71 88 〇0.03 X 〇36 10 1.0 74 68 〇0.01 X 〇37 25 1.0 72 80 〇0.02 X 〇38 EG(1) 60 1.0 75 90 〇0.00 X 〇39 75 1.0 76 98 〇-0.01 X 〇40 10 0.6 150 18 〇0.01 X 〇41 25 0.6 142 27 〇-0.01 X 〇42 60 0.6 153 50 〇0.02 X 〇43 75 0.6 146 71 〇0.03 X 〇44 EG(2) 40 0.6 150 40 〇0.51 X 〇45 EG(3) 40 0.6 146 41 〇0.73 X 〇46 EG(4) 40 0.5 149 39 〇0.98 X 〇47 EG(5) 40 0.6 156 37 〇1.32 X 〇48 EG(6) 40 0.6 143 42 〇1.78 X 〇49 ZN 40 0.6 163 35 〇3.40 〇◎ 50 ZF 40 0.6 158 36 〇3.97 〇◎ 51 40 0.5 179 41 〇-0.54 X 〇52 1.1 47 100 or more X -0.56 XX 53 GI 10 0.5 175 20 〇 -0.60 X 〇54 25 0.5 172 28 〇-0.57 X 〇55 60 0.5 180 55 〇-0.54 X 〇56 75 0.5 184 69 〇-0 .58 X 〇57 0.5 178 38 〇4.11 〇◎ 58 40 1.2 76 78 〇4.12 〇◎ 59 1.6 53 100 or more X 4.15 〇X 60 10 1.2 78 56 〇4.13 〇◎ 61 25 1.2 75 67 〇4.16 〇◎ 62 CR 60 1.2 73 84 〇 4.12 〇 ◎ 63 75 1.2 76 97 〇 4.12 〇 ◎ 64 10 0.5 178 19 〇 4.12 〇 ◎ 65 25 0.5 175 26 〇 4.14 〇 ◎ 66 60 0.5 170 55 〇 4.09 〇 ◎ 67 75 0.5 173 82 〇 4.11 〇◎ -36- (33) (33)200806468 These results can be examined as follows. First, the results of using the alloyed hot-dip galvanized steel sheet as the plated raw material sheet (Νο·1 to 32 in Table 2) were examined. In the present embodiment, conductivity and electromagnetic wave absorptivity were evaluated using a total of five kinds of raw material sheets (GA (1) to GA (5)) having different plating adhesion amounts. Among them, No. 1 to 16 are examples in which an alloyed molten galvanized steel sheet (plating adhesion amount: 40 g/m2, Fe: 10%) is used as a plated raw material sheet. Since they are all alloyed hot-dip galvanized steel sheets, good electromagnetic absorption can be obtained. As shown in Table 2, No. 1 to 7, 9 to 16 in which PPIt was controlled at 70 or more was superior in conductivity to N 〇.8 in which PPIt did not satisfy the range of the present invention. In detail, the larger the PPIT, the smaller the resistance 値, and the conductivity has a tendency to lift the cylinder. Further, when the relationship between the Tg of the resin film and the electric resistance 値 is examined, it is as follows. First, the case where the average thickness of the resin film was 1.9 μm was examined. Νο·7 ( Tg = 40°C ), Νο·9 ( Tg = 1 (TC ) ' No.10 ( Tg =25〇C ) > No.11 ( Tg= 60°C ) , N o · 12 ( The PPIt of T g = 7 5 〇C ) is about 78 to 83, which is set near the lower limit 70( 70 ) prescribed by the present invention, but it can be seen when comparing their resistance 値, and the lower the Tg is substantially the resistance 値The smaller the conductivity, the higher the conductivity. The same tendency is observed when the average thickness of the resin film is Ι.Ομπι. No. 4 (Tg = 40 ° C), No. l3 (Tg = 10 ° C) ) > No.14 ( -37- 200806468 (34)

The PPIt of Tg=25〇C), No.l5 (Tg=60°C) and No.l6 (Tg=75°C) are all about 179~185, and the control is within the range specified by the present invention (PPIt 2 7). 0), but when the resistance 値 is compared, the lower the Tg, the smaller the resistance 基本上, and the higher the conductivity. In the example (Νο·17 to 29) in which the amount of plating adhesion is different from that of the above-described GA (1) (Νο· 17 to 29), the same tendency as described above is similarly observed.

In addition, as the plated raw material plate, Νο·30 to 32 of GA (3) to GA (5) having different plating adhesion amounts are used, and PPIt satisfies the scope of the present invention, so that good electrical conductivity can be ensured. Since they use an alloyed molten galvanized steel sheet, electromagnetic wave absorbability is also excellent. In another aspect, Νο. 49 and 50 of Table 3 are examples of alloy-plated steel sheets using zinc and iron group elements other than the above-described mineral-coated raw material sheets. Specifically, No. 49 is an example of a steel sheet in which Ζη and Ni are alloyed by an electroplating method, and Νο·50 is an example of a steel sheet in which Zn and Fe alloys are Φ by electroplating, but their PPIts are In the range of the present invention, it is possible to ensure good electrical conductivity and to be excellent in electromagnetic wave absorptivity. On the other hand, Nos. 33 to 48 of Table 3 are examples in which an electrogalvanized steel sheet is used as a plated raw material plate. In the present embodiment, conductivity and electromagnetic wave absorptivity were evaluated using a total of six kinds of raw material sheets (EG(1) to EG(6)) having different plating adhesion amounts. As shown in Table 3, the pipp of the above-mentioned steel sheet was controlled to be 7 Å or more, and therefore, the electric conductivity was excellent. In detail, it can be seen that the larger the PPIt is, the more the resistance 値 -38-(35) 200806468 is, the smaller the conductivity is. On the other hand, it was confirmed by experiments that PPIt does not satisfy the use of any of the plated raw material sheets of the present invention, and the conductivity is poor (not shown in the table). Further, when the relationship between the T g and the resistance 値 of the resin film is examined, the above is considered. First, the case where the average thickness of the resin film is Ι.Ομπι is observed. Table 3 Ν 〇 · 3 5 ( T g = 4 0 °C ) , ο ο · 3 6 ( T g = 1 0 °C No.37 ( Tg = 25C ) , Νο·38 ( TTg: 60〇C ) The PPIt of No. 39 (75C) is about 71 to 76, which is set near the lower limit of the invention (PP It II 70), but the resistance is visible. The lower the Tg, the more the resistance is. Small, the conductivity has a tendency to lift. When the average thickness of the resin film is 0.6 μm, the same direction is also observed. Νο·33 (Tg = 40〇C), Νο·40 (Tg = 1 0 〇C), No.

T g — 2 5 ° C ) ' No. 42 ( Tg = 60 ° C ) ' No. 43 ( Tg = 75 ° C PPIt is approximately 142 to 153, controlled in the scope of the invention (PPIt- 70) However, when comparing their resistance 値, it is obvious that the resistance 値 is basically smaller, and the conductivity tends to increase. No. 5 1 to 56 of Table 3 is a molten steel sheet used as a mineral-coated raw material sheet. In the case where the PPIt satisfies the scope of the present invention, No. 51 and 53 to 56 are excellent in electrical conductivity as compared with No. 52 which satisfies the scope of the present invention. Further, since the steel sheets are all made of a hot-dip galvanized steel sheet, electrosorption is performed. Poor. The range is as follows:) Tg- 値 値 闻 41 41 41 ( ( ( ( ( ( ( ( ( ( ( ( ( ( - - - - - - - - - - - - - - - - - - - - - - - - - - - - - An example of a cold rolled steel sheet is used for the plated raw material sheet. Among them, No. 57 to 58, 60 to 67 in which PPIt satisfies the scope of the present invention is superior in conductivity to No. 59 which does not satisfy the scope of the present invention. Further, since all of the steel sheets described above are cold-rolled steel sheets, good electromagnetic wave absorption can be obtained as compared with the case of using alloyed plated steel sheets. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a view for explaining the concept of P PI of the S A E standard. Fig. 2 is a view for explaining a method of evaluating electromagnetic wave absorption performance of a coated steel sheet. Fig. 3 is a view for explaining a state in which the amount of reflection of the input electromagnetic wave is small due to the resonance frequency of the casing. Fig. 4 is a view schematically showing a state in which electromagnetic wave absorptivity is measured. Fig. 5 is a view for explaining a method of measuring conductivity of a resin-coated metal sheet. Fig. 6 is an explanatory view showing a s u S frame (frame) constituting a casing for measuring electromagnetic wave absorptivity. Fig. 7 is an explanatory view showing the shape of a sample steel sheet disposed on the left and right side surface portions of the frame. Fig. 8 is an explanatory view showing the shape of a sample steel sheet disposed on the upper portion and the bottom portion of the frame. -40 - (37) (37)200806468

[Main component symbol description] 1 : Frame 5 : High frequency loop antenna 6 : Coaxial cable 7 : Network analyzer -41

Claims (1)

(1) 200806468 X. Patent Application No. 1. A resin-coated metal sheet obtained by coating a resin film on a surface of a metal sheet, wherein the resin film satisfies the requirement of the following formula (1), PPIt-70. ..... (1) The PPIt table is not in the ppi (peaks Per Inch) described in SAE J91 1 -1986, when 1/2 of the peak level (2H) is used as the thickness of the resin film ί(μπι) The number of peak-to-valley counts. The resin-coated metal sheet according to the first aspect of the invention, wherein the resin film has a glass transition point (Tg) of 60 ° C or lower. The resin-coated metal sheet according to the first aspect of the invention, wherein the metal sheet is an alloy-plated steel sheet of zinc and an iron group element. The resin-coated metal sheet according to any one of claims 1 to 3, wherein the metal sheet is an alloyed hot-dip galvanized steel sheet. -42-