201006377 六、發明說明： 【發明所屬之技術領域】 本發明有關一種自Ni-Zn鐵素體燒結體所構成之抑制 雜訊薄片，更詳言之，係提供一種藉由控制Ni-Zn鐵素體 (ferrite )材料之複導磁率（complex magnetic permeability )與體積電阻率，於貼附於電路上時在 10MHz至1 GHz下之電磁波反射量少之抑制雜訊薄片。 【先前技術】 近幾年來，數位電子設備有驚人的進步，尤其是以行 動電話、數位相機或筆記型電腦爲代表之行動電子設備， 顯著要求有動作訊號之高頻化·小型化或輕量化，電子零 件或電路基板之高密度安裝被舉出爲最大的技術課題之一 〇 由於電子設備的電子零件或電路基板之高密度安裝與 ® 動作訊號之高頻化進展，故無法去除發生雜訊之零件與其 他零件之距離，而於電子電路或電路基板上貼附用以抑制 自電子設備之微處理器、LSI或液晶面板等所放射之不需 要輻射之抑制雜訊薄片。其使甩時，若自抑制雜訊薄片之 反射量大，則其反射波因必要訊號的干涉而有引起電子零 件錯誤動作之可能性。因此，如專利文獻1之記載「 [0007]強烈要求有電磁波反射少之電磁波干涉抑制用薄 片」，而其望有電磁波反射少的抑制雜訊薄片。 如本用途之於附近電磁場之電磁波吸收反射現象，利 -5- 201006377 用於在電波暗室或建築物壁面使用之電波吸收體（專利文 獻2)之設計的傳送線路理論（遠方電磁場處理理論）難 以解析，故抑制雜訊薄片之設計倚賴於經驗的部分相當大 (非專利文獻1 )。 於最近，如專利文獻1及專利文獻3所揭示，已廣泛 使用於樹脂中添加扁平狀或球狀金屬軟磁性粉末作爲軟磁 性粉末並成形爲薄片狀之抑制雜訊薄片。 又，專利文獻4中皆是有使用鐵素體燒結體之電磁波 @ 抑制體，於專利文獻5中則揭示使用鐵素體燒結體之電波 吸收體以及使用該電波吸收體之高頻電路用封裝。 另一方面，製作薄的薄片狀鐵素體燒結體時，令於樹 脂中混合鐵素體粉末之鐵素體成形薄片予以燒結。此時， 鐵素體成形薄片彼此間或燒結薄片固著於燒結用基座。由 於將固著之燒結薄片剝離時會使燒結薄片破損，故一般係 進行在燒結前之鐵素體成形薄片或燒結用基座表面上塗佈 用以防止固著之氧化锆粉末或氧化鋁粉末等之脫模粉末並 ❹ 予以燒結’於燒結後去除脫模粉末之方法。此等作業極其 煩雜，且脫模用粉末難以完全去除，故若使用於精密電子 零件等時’有脫模粉末污染設備之情況。又，脫模用粉末 凝集時，於燒結時產生拉力而使鐵素體燒結薄片產生起伏 ’最終產生破裂之頻度變高。作爲解決此之方法，於專利 文獻6中揭示有利用「於鐵素體成形體燒結之際使用之鐵 素體核心變形防止用鐵素體薄片」。 又’於專利文獻7中，作爲獲得天線一體型磁性薄片 -6- 201006377 ，揭示有將燒結鐵素體固片敷置在薄片基材上並接奢固定 之方法。 [專利文獻1]特開2007-288006號公報 [專利文獻2]特開平06-224583號公報 [專利文獻3]特開平7-2 12079號公報 [專利文獻4]特開2002-204094號公報 [專利文獻5]特開2004-6591號公報 [專利文獻6]特開平2-305416號公報 [專利文獻7]特開2006-174223號公報 [非專利文獻1 ]橋本修，「電波吸收體之動向」，電 子情報通訊學會誌，卷86，第10期，800〜803頁，2003 年10月 【發明內容】 [發明所欲解決之課題] ❹ 專利文獻1及專利文獻3，雖揭示於樹脂中添加扁平 狀或球狀金屬軟磁性粉末作爲軟磁性粉末並成形爲薄片狀 之抑制雜訊薄片，貼附此薄片時之反射量變大，故輸入訊 號與反射訊號產生干涉的可能性高。 於專利文獻2中揭示關於在電波暗室等使用之電波吸 收體，藉控制導磁率、體積電阻率及介電率，而提高在數 十MHz帶之吸收特性。 此電波吸收體，如非專利文獻1中所示，爲可藉由傳 送線路理論設計者，其吸收特性可藉由自導磁率、介電率 201006377 及電波吸收體厚度計算而求得。又，該專利文獻2中雖未 顯示，但電波吸收體厚度通常有必要爲5mm以上。因此 ，關於設計思想全然不同之雜訊吸收薄片，利用專利文獻 2之見解有其困難。 於專利文獻4中，雖揭示使用鐵素體燒結體之電磁波 抑制體，但有關鐵素體燒結體並無詳細記載，且有關自電 磁波抑制體之反射亦無記載。 於專利文獻5中，雖揭示使用鐵素體之電波吸收體及 @ 使用該電波吸收體之高頻電路用封裝，但作爲其對象之頻 率爲10GHz以上，遠高於本發明中作爲對象之頻率數範圍 。由於若對象的頻率數不同，設計思想亦不同，因此有關 本發明之雜訊吸收薄片，利用專利文獻5之見解有其困難 另一方面，於專利文獻6，雖揭示於鐵素體成形體燒 結之際使用鐵素體薄片，但此方法之生產性差，必須另外 準備鐵素體薄片本身，亦無法經濟地使用。 Θ 又，於專利文獻7中，雖揭示敷置鐵素體固片之方法 ，但將鐵素體固片效率良好地並排於薄片基材上有困難， 故而不實用。 因此，本發明之技術課題係提供一種在10 MHz至 1GHz中雜訊衰減量大且反射量少之由Ni-Zn鐵素體燒結 體所構成之抑制雜訊片。 再者，本發明之技術課題係提供一種殘留脫模粉末不 會污染電子設備等之由乾淨Ni-Zn鐵素體燒結體所構成之 -8- 201006377 抑制雜訊片。 [用以解決課題的手段] 前述技術課題可藉由下列之本發明達成。 亦即，本發明係一種抑制雜訊薄片，其特徵爲由厚度 爲30~400μιη、體積電阻率爲l_0xl0Q〜1.0χ103Ωιη、微帶線 (microstrip line)之評價中，於1GHz之反射量爲-20dB 0 以下，且吸收量爲25%以上之Ni-Zii鐵素體燒結體所構成 (本發明1 )。 又，本發明係如上述1記載之抑制雜訊薄片，其中 Ni-Zn鐵素體之組成換算成氧化物計，爲51~57莫耳％之 ?62〇3、8~23莫耳％之？^〇、2 5〜40莫耳％之211〇(本發明 2 )。 又，本發明係如上述1或2記載之抑制雜訊薄片，其 中抑制雜訊薄片之至少一表面之表面粗糙度，其中心線平 ❹ 均粗糙度爲130〜650nm，最大高度爲2~9μιη，且ΙΟΟμιη見 方之區域中於最大高度之50%深度沿水平方向截斷之剖面 面積佔有率爲5~70% (本發明3 )。 又，本發明係如上述3記載之抑制雜訊薄片，其中抑 制雜訊薄片之至少單面上設有溝槽（本發明4 )。 又，本發明係如上述3或4記載之抑制雜訊薄片，其 中抑制雜訊薄片之至少單面上貼附黏著薄膜，且於由Ni_ Zn鐵素體燒結體所構成之抑制雜訊薄片上設有裂縫（本 發明5)。 -9- 201006377 [發明效果] 本發明之抑制雜訊薄片，由於藉由控制複導磁率及體 積電阻率，而可控制於微帶線評價中於1 GHz之反射量爲-20dB以下，吸收量爲25 %以上，故貼附於電子電路時可 減低於10MHz至1 GHz之輸入訊號反射，且顯示吸收大的 雜訊吸收量。 又，依據本發明，提供一種抑制雜訊薄片，其即使未 © 進行氧化锆或氧化鋁粉末等之脫模處理亦可獲得未固著之 乾淨且薄的抑制雜訊薄片，於安裝於電子設備時亦無因脫 模粉末飛散等引起之污染。 【實施方式】 首先，就本發明之抑制雜訊薄片加以描述。 本發明之抑制雜訊薄片厚度爲30〜400 μιη。抑制雜訊 薄片厚度未達30μιη時，無法獲得於1GHz爲25%以上的 參 吸收量。抑制雜訊薄片之厚度超過4 00μιη時，吸收量雖高 ，但由於貼附於偏向薄型之電子設備內部時厚度過厚而不 佳。抑制雜訊薄片厚度較好爲35〜3 80 μιη。 本發明之抑制雜訊薄片之體積電阻率爲1.0x10°〜1.Ox 103Ωπι。Ni-Zn系鐵素體無法獲得體積電阻率小於l.Ox lOMm之抑制雜訊薄片。抑制雜訊薄片之體積電阻率若超 過1.0χ103Ωπι時，由於吸收量降低故而不佳。抑制雜訊薄 片之體積電阻率較好爲更好爲1.8χ -10- 201006377 10。〜7_3χ102Ωιη。 本發明之抑制雜訊薄片於微帶線評價中，於1GHz之 反射量爲-20(18、吸收量爲25%以上。反射量超過-20(18時 及吸收量未達2 5 %時，無法獲得電磁波反射少之抑制雜訊 薄片。反射量之下限値爲-40 dB左右，吸收量上限値爲 5 0 %左右。 本發明之抑制雜訊薄片之於100MHz之複磁導率，較 φ 好 μ’爲 5~40，較好 μ”爲 30~1 10。 本發明之抑制雜訊薄片中，Ni-Zn鐵素體之組成，換 算爲氧化物計，較好爲 51.0〜57.0莫耳％之 Fe203、 8.0 〜23.0莫耳％ 之 NiO、25.0 〜40.0 莫耳 ％之 ZnO。201006377 VI. Description of the Invention: [Technical Field] The present invention relates to a noise suppression sheet composed of a sintered body of Ni-Zn ferrite, and more particularly, to provide a method for controlling Ni-Zn ferrite The complex magnetic permeability and volume resistivity of the ferrite material, which suppresses the noise sheet at a frequency of 10 MHz to 1 GHz when the electromagnetic wave is reflected on the circuit. [Prior Art] In recent years, digital electronic devices have made amazing progress, especially mobile electronic devices such as mobile phones, digital cameras, or notebook computers. There is a significant demand for high-frequency, miniaturization or weight reduction of motion signals. High-density mounting of electronic components or circuit boards is cited as one of the biggest technical issues. Due to the high-density mounting of electronic components or circuit boards of electronic equipment and the high frequency of the motion signals, it is impossible to remove noise. The distance between the component and the other component is attached to the electronic circuit or the circuit board to suppress the noise suppression thin film emitted from the microprocessor, LSI or liquid crystal panel of the electronic device. In the case of 甩, if the amount of reflection of the self-suppressing noise sheet is large, the reflected wave may cause an erroneous operation of the electronic component due to interference of the necessary signal. Therefore, as described in the Patent Document 1, "the electromagnetic wave interference suppressing sheet having less electromagnetic wave reflection is strongly required", and the noise suppression sheet having less electromagnetic wave reflection is expected. If the electromagnetic wave absorption and reflection phenomenon of the electromagnetic field in the vicinity is used for this purpose, the transmission line theory (the far-field electromagnetic field treatment theory) designed for the design of the radio wave absorber (Patent Document 2) used in the anechoic chamber or the wall of the building is difficult. Since the analysis is suppressed, the part that suppresses the design of the noise sheet depends on experience (Non-Patent Document 1). Recently, as disclosed in Patent Document 1 and Patent Document 3, a noise-inhibiting sheet in which a flat or spherical metal soft magnetic powder is added as a soft magnetic powder and formed into a sheet shape is widely used. Further, in Patent Document 4, there is an electromagnetic wave suppressor using a ferrite sintered body, and Patent Document 5 discloses a radio wave absorber using a ferrite sintered body and a package for a high-frequency circuit using the radio wave absorber. . On the other hand, when a thin flaky ferrite sintered body is produced, the ferrite formed sheet in which the ferrite powder is mixed in the resin is sintered. At this time, the ferrite formed sheets or the sintered sheets are fixed to the sintering susceptor. Since the sintered flakes are broken when the fixed sintered flakes are peeled off, the zirconia powder or the alumina powder for preventing fixation is generally applied to the surface of the ferrite formed sheet or the sintered base before sintering. The method of removing the mold release powder after sintering is performed by sintering the powder. These operations are extremely cumbersome, and it is difficult to completely remove the powder for mold release. Therefore, when used in precision electronic parts or the like, there is a case where the mold release powder contaminates the equipment. Further, when the powder for mold release is aggregated, a tensile force is generated during sintering to cause undulation of the ferrite sintered flakes, and the frequency of occurrence of cracking eventually becomes high. As a method for solving this problem, Patent Document 6 discloses a ferrite core sheet for preventing deformation of a core body used for sintering a ferrite body. Further, in Patent Document 7, as an antenna-integrated magnetic sheet -6-201006377, a method of depositing a sintered ferrite sheet on a sheet substrate and attaching it to it is disclosed. [Patent Document 1] JP-A-2002-204094 [Patent Document 3] JP-A-2002-204094 (Patent Document 4) JP-A-2002-204094 [Patent Document 7] JP-A-2002-174223 [Patent Document 7] JP-A-2006-174223 [Non-Patent Document 1] Hashimoto Sho, "The Trend of Radio Wave Absorbers Electronic Information and Communication Society, Vol. 86, No. 10, pp. 800-803, October 2003 [Invention] [Problems to be Solved by the Invention] 专利 Patent Document 1 and Patent Document 3 are disclosed in the resin. When a flat or spherical metal soft magnetic powder is added as a soft magnetic powder and formed into a sheet-like noise suppression sheet, the amount of reflection when the sheet is attached becomes large, so that there is a high possibility that the input signal and the reflection signal interfere with each other. Patent Document 2 discloses that the radio wave absorber used in an anechoic chamber or the like improves the absorption characteristics in a tens of MHz band by controlling the magnetic permeability, the volume resistivity, and the dielectric constant. This radio wave absorber, as shown in Non-Patent Document 1, is a design that can be designed by a transmission line theory, and its absorption characteristics can be obtained by calculation of self-magnetic permeability, dielectric constant 201006377, and thickness of a radio wave absorber. Further, although not shown in Patent Document 2, the thickness of the radio wave absorber is usually required to be 5 mm or more. Therefore, with regard to the noise absorbing sheet in which the design concept is completely different, it is difficult to use the knowledge of Patent Document 2. In Patent Document 4, an electromagnetic wave suppressor using a ferrite sintered body is disclosed. However, the ferrite sintered body is not described in detail, and the reflection from the electromagnetic wave suppressor is not described. Patent Document 5 discloses a radio wave absorber using a ferrite and a package for a high-frequency circuit using the radio wave absorber. However, the frequency of the target is 10 GHz or more, which is much higher than the target frequency in the present invention. Number range. Since the design of the noise absorption sheet of the present invention is different depending on the frequency of the object, the knowledge of the patent document 5 is difficult. On the other hand, in Patent Document 6, it is disclosed that the ferrite formed body is sintered. Ferrite flakes are used, but the productivity of this method is poor, and the ferrite flakes themselves must be separately prepared and cannot be used economically. Further, in Patent Document 7, although a method of depositing a ferrite solid sheet is disclosed, it is difficult to efficiently arrange the ferrite sheets on the sheet base material, which is not practical. Accordingly, the technical problem of the present invention is to provide a noise suppressing sheet comprising a Ni-Zn ferrite sintered body having a large amount of noise attenuation and a small amount of reflection in 10 MHz to 1 GHz. Further, the technical problem of the present invention is to provide a -8-201006377 suppression noise absorbing sheet composed of a clean Ni-Zn ferrite sintered body which does not contaminate an electronic device or the like. [Means for Solving the Problems] The above technical problems can be achieved by the following invention. That is, the present invention is a noise suppression sheet characterized by a thickness of 30 to 400 μm, a volume resistivity of 1_0x10Q to 1.0χ103Ωιη, and a microstrip line, and the reflection amount at 1 GHz is -20 dB. 0 or less, and the Ni-Zii ferrite sintered body having an absorption amount of 25% or more is constituted (Invention 1). Further, the present invention is the noise suppression sheet according to the above 1, wherein the composition of the Ni-Zn ferrite is converted to an oxide of 51 to 57 mol%, 62 〇 3, and 8 to 23 mol%. ? ^〇, 2 5~40 mol% of 211〇 (Inventive 2). Further, the present invention is the noise suppression sheet according to the above 1 or 2, wherein the surface roughness of at least one surface of the noise sheet is suppressed, and the center line has a flat roughness of 130 to 650 nm and a maximum height of 2 to 9 μm. And the area ratio of the cross-sectional area cut off in the horizontal direction at a depth of 50% of the maximum height in the region of ΙΟΟμιη square is 5 to 70% (Invention 3). Further, the present invention is the noise suppression sheet according to the above 3, wherein the noise suppression sheet is provided with a groove on at least one surface thereof (Invention 4). Further, the present invention is the noise suppression sheet according to the above 3 or 4, wherein the adhesion film is adhered to at least one side of the noise suppression sheet, and the noise suppression sheet is formed of the Ni_Zn ferrite sintered body. A crack is provided (Invention 5). -9- 201006377 [Effect of the Invention] The noise suppression sheet of the present invention can be controlled by the control of the magnetic permeability and the volume resistivity, and the amount of reflection at 1 GHz in the evaluation of the microstrip line is -20 dB or less. It is more than 25%, so it can be reduced to input signal reflection below 10MHz to 1 GHz when attached to an electronic circuit, and it shows a large absorption of noise. Further, according to the present invention, there is provided a noise suppression sheet which can obtain an unfixed clean and thin noise suppression sheet even if it is subjected to a release treatment such as zirconia or alumina powder, and is mounted on an electronic device. There is also no pollution caused by the scattering of the release powder. [Embodiment] First, the noise suppression sheet of the present invention will be described. The noise suppression sheet of the present invention has a thickness of 30 to 400 μm. When the thickness of the noise suppression sheet is less than 30 μm, the amount of absorption of 25% or more at 1 GHz cannot be obtained. When the thickness of the noise suppression sheet is more than 400 μm, the absorption amount is high, but it is not preferable because the thickness is too thick when attached to the inside of the thin electronic device. The thickness of the noise suppression sheet is preferably from 35 to 3 80 μm. The volume resistivity of the noise suppression sheet of the present invention is 1.0 x 10 ° to 1. Ox 103 Ω π. Ni-Zn ferrite cannot obtain a noise suppression sheet having a volume resistivity of less than 1.0×10 Mm. When the volume resistivity of the noise suppression sheet is over 1.0 χ 103 Ω π, the absorption amount is lowered, which is not preferable. The volume resistivity of the noise suppressing film is preferably 1.8 χ -10- 201006377 10. ~7_3χ102Ωιη. In the microstrip line evaluation of the noise suppression sheet of the present invention, the reflection amount at 1 GHz is -20 (18, the absorption amount is 25% or more. When the reflection amount exceeds -20 (at 18 hours and the absorption amount is less than 25%, It is impossible to obtain a noise suppression sheet with less electromagnetic wave reflection. The lower limit of the reflection amount is about -40 dB, and the upper limit of the absorption amount is about 50%. The complex magnetic permeability of the noise suppression sheet of the present invention at 100 MHz is higher than φ. Preferably, μ' is 5 to 40, preferably μ" is 30 to 1 10. In the noise suppression sheet of the present invention, the composition of Ni-Zn ferrite is converted to an oxide meter, preferably 51.0 to 57.0 m. % of Fe203, 8.0 to 23.0 mol% of NiO, 25.0 to 40.0 mol% of ZnO.
Ni-Zn鐵素體之組成中Fe含量在上述組成範圍之外時 ，體積電阻率變成大於1·〇Χΐ〇3Ωιη，無法或的高吸收量。 更好Fe含量爲51.0-56.5莫耳％，更好爲5 1.5〜56.0莫耳 %。 ® 又，Ni含量在前述組成範圍外時，藉由使複導磁率之 μ”變低使吸收量變小。更好Ni含量爲9.0〜22.5莫耳％， 又更好爲9.5〜22.0莫耳。 又，Zn含量在前述組成範圍外時，藉由使複導磁率 之μ”變低使吸收量變小。更好Zn含量爲25.0〜39.0莫耳％ ，又更好爲25.5〜38_5吴耳。 本發明之抑制雜訊薄片之至少一表面上之表面粗糙度 ，較好爲中心線平均粗糙度爲130〜650nm，最大高度較好 爲 2.0〜9_0μιη。 -11 - 201006377 關於表面粗糙度，若中心線平均粗糙度（Ra)未達 130nm、最大高度（Rmax)未達2.0μιη，則燒結時會使薄 片固著。 關於表面粗糙度，若中心線平均粗糙度（Ra)超過 650nm、或最大高度（Rmax)超過9.0μηι，則將失去平滑 性，變成易龜裂，變成易於與絕緣薄膜或導電層之界面混 入空隙等。又，燒結體之剖面積降低且導磁率降低。 本發明之抑制雜訊薄片，較好爲具有前述中心線平均 粗糙度（Ra)或前述最大高度（Rmax )之値同時控制表 面凹凸之存在頻率。關於求得表面粗糙度之ΙΟΟμπι見方影 像之方位（Bearing )解析中，於最大高度之50%深度朝水 平方向截斷之截斷面面積之佔有率較好爲5〜70%。 本發明之抑制雜訊薄片較好於由Ni-Zn鐵素體所構成 之抑制雜訊薄片之至少單面上設有溝槽。 藉由設置溝槽，爲了防止貼附後述黏著薄膜之抑制雜 訊薄片之非預期之龜裂，可預先沿著溝槽於抑制雜訊薄片 上預先設置裂縫（若於破裂時，以使不成爲不規則形狀之 方式預先割成預先決定之形狀）。亦即，亦可爲於黏著薄 膜上貼附有預先割成所需形狀之抑制雜訊薄片之形狀。 本發明之抑制雜訊薄片亦可爲於由Ni-Zn鐵素體燒結 體所構成之抑制雜訊薄片之至少單面上貼附黏著薄膜且於 由Ni-Zn鐵素體燒結體所構成之抑制雜訊薄片上設置裂縫 藉由貼附黏著薄膜，即使於設置裂縫後Ni-Zn鐵素體 201006377 燒結體亦不會飛散，而可獲得有彎曲性之抑制雜訊薄片。 接著，描述本發明之抑制雜訊薄片之製造方法。 本發明之抑制雜訊薄片係製作鐵素體成型薄片後，經 燒結，獲得由Ni_Zn鐵素體燒結體所構成之抑制雜訊薄片 者。 本發明之鐵素體成型薄片可藉由下列方法獲得：於熱 可塑性樹脂及/或熱可塑性彈性體中熔融混合鐵素體粉末 φ 並藉砑光輥或模具加壓成型而薄片化之方法，將分散有鐵 素體粉末之塗料塗佈於塑膠薄膜上之方法等。 本發明中，視需要，藉由於鐵素體成型薄片上形成特 定凹凸並燒成，可獲得相互薄片不固著而具有所需表面粗 糙度之抑制雜訊薄片。 獲得本發明之鐵素體成型薄片之方法並無特別限定’ 但本發明之鐵素體成型薄片表面之粗面加工方法可使用廣 泛利用金屬硏磨等之噴砂加工。亦即，於鐵素體成型薄片 〇 上噴射於水溶液中分散有作爲硏磨劑之玻璃、氧化鋁等之 溶液，藉由水洗，獲得經粗面加工之鐵素體成型薄片。 又，獲得本發明鐵素體成型薄片之其他方法’有於熱 可塑性樹脂及/或熱可塑性彈性體中熔融混合鐵素體粉末 ，藉由砑光輥或表面加工之模具加壓成型而薄片化之方法 。又，視需要，藉由使用預先表面加工（凹凸硏磨）之砑 光輥或表面經加工之模具加壓，可獲得經粗面加工之鐵素 體成型薄片。When the Fe content in the composition of the Ni-Zn ferrite is outside the above composition range, the volume resistivity becomes greater than 1·〇Χΐ〇3 Ω ηη, and the high absorption amount cannot be. The Fe content is preferably 51.0-56.5 mol%, more preferably 5 1.5~56.0 mol%. Further, when the Ni content is outside the above composition range, the absorption amount becomes small by lowering the μ of the double magnetic permeability. The Ni content is preferably 9.0 to 22.5 mol%, more preferably 9.5 to 22.0 mol. Further, when the Zn content is outside the above composition range, the absorption amount is made small by lowering the μ of the complex magnetic permeability. The better Zn content is 25.0~39.0 mol%, and more preferably 25.5~38_5 wu. The surface roughness of at least one surface of the noise suppression sheet of the present invention is preferably from 130 to 650 nm, and the maximum height is preferably from 2.0 to 9_0 μm. -11 - 201006377 Regarding the surface roughness, if the center line average roughness (Ra) is less than 130 nm and the maximum height (Rmax) is less than 2.0 μm, the sheet will be fixed during sintering. When the center line average roughness (Ra) exceeds 650 nm or the maximum height (Rmax) exceeds 9.0 μm, the smoothness is lost and the crack is easily broken, and it becomes easy to mix into the gap with the interface of the insulating film or the conductive layer. Wait. Further, the cross-sectional area of the sintered body is lowered and the magnetic permeability is lowered. The noise suppression sheet of the present invention preferably has a center line average roughness (Ra) or a maximum height (Rmax) as described above while controlling the frequency of occurrence of surface irregularities. Regarding the surface roughness obtained by the ΙΟΟμπι square image, the occupation ratio of the cross-sectional area cut at a depth of 50% of the maximum height in the horizontal direction is preferably 5 to 70%. The noise suppression sheet of the present invention preferably has a groove provided on at least one side of the noise suppression sheet composed of Ni-Zn ferrite. By providing a groove, in order to prevent unintended cracking of the noise-sensitive film by attaching an adhesive film to be described later, a crack may be previously provided on the noise suppression sheet along the groove (if it is broken, so as not to become The irregular shape is pre-cut into a predetermined shape). That is, it is also possible to attach a shape of the noise suppression sheet which is previously cut into a desired shape to the adhesive film. The noise suppression sheet of the present invention may be formed by adhering an adhesive film to at least one surface of a noise suppression sheet composed of a sintered body of Ni-Zn ferrite and being formed of a sintered body of Ni-Zn ferrite. By suppressing the provision of cracks on the noise sheet by attaching the adhesive film, even if the crack is formed, the Ni-Zn ferrite 201006377 sintered body does not scatter, and a bend suppressing noise sheet can be obtained. Next, a method of manufacturing the noise suppression sheet of the present invention will be described. In the noise suppression sheet of the present invention, a ferrite formed sheet is produced, and after sintering, a noise suppressing sheet composed of a sintered body of Ni_Zn ferrite is obtained. The ferrite-molded sheet of the present invention can be obtained by melt-mixing a ferrite powder φ in a thermoplastic resin and/or a thermoplastic elastomer and extruding it by a calender roll or a die press molding, A method of applying a coating material in which a ferrite powder is dispersed on a plastic film. In the present invention, if necessary, irregularities are formed on the ferrite-formed sheet and fired, whereby a noise-inhibiting sheet having a desired surface roughness without being fixed to each other can be obtained. The method of obtaining the ferrite-molded sheet of the present invention is not particularly limited. However, the rough surface processing method of the surface of the ferrite-molded sheet of the present invention can be subjected to sandblasting using a metal honing or the like. Namely, a solution of glass, alumina or the like as a honing agent is dispersed in an aqueous solution by spraying on a ferrite-molded sheet, and a rough-processed ferrite-formed sheet is obtained by washing with water. Further, another method for obtaining a ferrite-molded sheet of the present invention is to melt-mix ferrite powder in a thermoplastic resin and/or a thermoplastic elastomer, and to form a sheet by press molding of a calender roll or a surface-machining mold. The method. Further, if necessary, a rough-processed ferrite-molded sheet can be obtained by pressurizing a calender roll or a surface-processed mold which has been previously subjected to surface processing (obtrusion honing).
作爲熱可塑性樹脂可使用聚乙烯（PE)、聚丙烯（PP -13- 201006377 )、聚乙烯縮丁醛（PVB )等。又，作爲熱可塑性彈性體 可使用苯乙烯·乙烯·丁烯系等之樹脂。視需要亦可混合 兩種以上之熱可塑性樹脂及/或熱可塑性彈性體。就燒結 時之熱分解性等而言，可較好地使用低密度聚乙烯（ LDPE )或聚乙烯縮丁醛（PVB )等。 組成爲對1000重量份鐵素體粉未處理5~50重量份偶 合劑，較好相對於經偶合劑處理之鐵素體粉末1 0 00重量 份，成爲熱可塑性樹脂20〜1〇〇重量份。更好的組成範圍 @ 爲經偶合劑處理之鐵素體粉末1 000重量份爲熱可塑性樹 脂30〜80重量份。 前述鐵素體粉末與熱可塑性樹脂之混合物以加壓捏合 機等在12 0〜140 °C混練20〜60分鐘後，使用加壓模具（視 需要，爲表面經凹凸加工之加壓模具）而成型。 獲得本發明鐵素體成型薄片之其他方法，有於塑膠薄 膜上塗佈分散有鐵素體粉末之塗料之方法。分散有鐵素體 粉末之塗料之調配組成爲相對於鐵素體粉未1〇〇重量份， 參 聚乙烯醇樹脂爲5~12重量份，作爲可塑劑之丁基苯二甲 酸丁酯爲1〜8重量份，溶劑爲30〜100重量份。 作爲溶劑可使用二醇醚系或MEK、甲苯、甲醇、乙醇 、正丁醇等。若考慮鐵素體粉末之分散性或混合作業性或 乾燥性等，作爲塗料之較佳調配組成範圍爲相對於鐵素體 粉末100重量份，聚縮丁醛爲6~ 11重量份，丁基苯二甲 酸丁酯爲1〜6重量份，溶劑爲30〜80重量份。 至於鐵素體粉末之分散塗料的製造方法並未特別限定 -14- 201006377 ，較好使用球磨機。先塡充並混合溶劑與鐵素體粉末後， 添加樹脂及可塑劑並混合獲得均勻塗料。爲了防止所得塗 料於塗佈乾燥之際於塗膜發生龜裂，較好以真空容器充分 進行減壓脫泡。 鐵素體分散塗料之塗佈方法並無特別限制，可使用輥 塗佈器或刮刀塗佈器。由膜厚精度或塗料安定性觀之，較 好使用刮刀塗佈器。由刮刀塗佈器於塑膠薄膜上塗部所需 φ 厚度，於80〜130°C乾燥30〜60分鐘，可獲得鐵素體成型 薄片。 鐵素體分散塗料之塗佈用塑膠薄膜並無特別限制，但 可使用聚乙烯（PE)、聚丙烯（PP)、聚對苯二甲酸乙二 酯（PET )、聚醯亞胺等各種薄膜。由薄膜表面加工性或 塗佈乾燥時之熱安定性觀之，較好爲聚對苯二甲酸乙二酯 (PET )薄膜。 依據需要而於鐵素體成型薄片表面上賦予特定凹凸時 φ ，可使用對前述各種薄膜噴砂加工者。藉由使用經噴砂處 理之塑膠薄膜，可對鐵素體成型薄片上轉印塑膠薄膜之凹 凸，可獲得具有所需表面粗糙度之成型薄片。 本發明中，將前述鐵素體成型薄片燒結，獲得抑制雜 訊薄片。As the thermoplastic resin, polyethylene (PE), polypropylene (PP-13-201006377), polyvinyl butyral (PVB), or the like can be used. Further, as the thermoplastic elastomer, a resin such as styrene-ethylene/butylene or the like can be used. Two or more thermoplastic resins and/or thermoplastic elastomers may be mixed as needed. As the thermal decomposition property at the time of sintering, etc., low density polyethylene (LDPE), polyvinyl butyral (PVB), or the like can be preferably used. The composition is prepared by treating 5 to 50 parts by weight of the coupling agent for 1000 parts by weight of the ferrite powder, preferably 100 parts by weight of the ferrite powder treated with the coupling agent, to be 20 to 1 part by weight of the thermoplastic resin. . A better composition range @1 parts by weight of the ferrite powder treated with the coupling agent is 30 to 80 parts by weight of the thermoplastic resin. The mixture of the ferrite powder and the thermoplastic resin is kneaded at 120 to 140 ° C for 20 to 60 minutes by a pressure kneader or the like, and then a press mold (if necessary, a pressure mold having a surface subjected to uneven processing) is used. forming. Another method of obtaining the ferrite formed sheet of the present invention is a method of coating a coating film on which a ferrite powder is dispersed on a plastic film. The composition of the coating in which the ferrite powder is dispersed is not more than 1 part by weight relative to the ferrite powder, 5 to 12 parts by weight of the polyvinyl alcohol resin, and butyl butyl phthalate as a plasticizer is 1 To 8 parts by weight, the solvent is 30 to 100 parts by weight. As the solvent, a glycol ether system, MEK, toluene, methanol, ethanol, n-butanol or the like can be used. Considering the dispersibility of the ferrite powder, the mixing workability, the drying property, etc., the composition ratio of the coating is preferably from 6 to 11 parts by weight, based on 100 parts by weight of the ferrite powder, of the butyl group. The butyl phthalate is 1 to 6 parts by weight, and the solvent is 30 to 80 parts by weight. The method for producing the dispersion coating of the ferrite powder is not particularly limited to -14 to 201006377, and a ball mill is preferably used. After filling and mixing the solvent and the ferrite powder, a resin and a plasticizer are added and mixed to obtain a uniform coating. In order to prevent the coating material from being cracked on the coating film during coating drying, it is preferred to sufficiently defoam the vacuum in a vacuum vessel. The coating method of the ferrite dispersion coating is not particularly limited, and a roll coater or a knife coater can be used. From the viewpoint of film thickness precision or paint stability, it is preferable to use a blade coater. The φ thickness is applied to the plastic film by a knife coater, and dried at 80 to 130 ° C for 30 to 60 minutes to obtain a ferrite formed sheet. The plastic film for coating a ferrite dispersion coating is not particularly limited, but various films such as polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), and polyimide may be used. . From the viewpoint of the surface processability of the film or the thermal stability at the time of coating drying, a polyethylene terephthalate (PET) film is preferred. When a specific unevenness φ is imparted to the surface of the ferrite-molded sheet as needed, the above-mentioned various film blasting machines can be used. By using a sandblasted plastic film, the concave shape of the plastic film can be transferred onto the ferrite formed sheet to obtain a formed sheet having a desired surface roughness. In the present invention, the ferrite formed sheet is sintered to obtain a noise suppressing sheet.
本發明之抑制雜訊薄片之燒結，工業上較好以在氣孔 率30 %之氧化鋁板上重疊5 ~20片左右之本發明之鐵素體 成型薄片而進行。燒結條件，較好設有使用電爐等除去樹 脂成分即使鐵素體粒子成長之製程。樹脂除去係在1 50°C -15- 201006377 〜550°C歷時5~80小時之條件進行，鐵素體粒子之成長係 在1100°C〜1 300°C歷時1〜5小時之條件進行。成長時之溫 度未達1100°C時，無法獲得具有所需反射量及吸收量之抑 制雜訊薄片。 爲了防止薄片之加熱變形或裂開，樹脂成份去除較好 以10〜20°c/小時左右自室溫升溫後保持一定溫度。又隨後 ，可適當地以30〜60°C/小時升溫後保持一定溫度充分使燒 結之鐵素體粒子成長後緩慢冷卻。又，各製程之保持溫度 © 貨時間，只要依據所處理之鐵素體成型薄片之片數選擇最 適條件即可。 本發明之抑制雜訊薄片可在至少單面上設有黏著薄膜 後，於基板中加入裂縫而對層合體賦予彎曲性後使用。 設於本發明之抑制雜訊薄片中之溝槽可於成型薄片之 單面上藉由壓花加工用輥或金屬刀刃等設置前端角度爲 25-45 m Z V型溝槽。 溝槽間隔較好爲溝槽合底間間隔爲l~5mm。若未達 參 1mm，則Ni-Zn鐵素體燒結體沿著溝槽彎折時之導磁率將 降低，又加工變困難。若超過5 mm，則Ni-Zn鐵素體燒結 體之撓曲性較低。溝槽更佳之間隔爲2〜4mm。 溝槽深度較好與成型薄片後度之比（溝槽深度/薄片 厚度）成爲0.4〜0.7。溝槽深度/薄片厚度之比若未達〇.4 ，則有沿著溝槽無法割開之情形，裂縫將成爲不均一而有 導磁率不安定之傾向。溝槽深度/薄片厚度之比若超過〇.7 ，則於燒成處理時有沿著溝槽裂開之情況。溝槽深度之更 -16- 201006377 佳範圍爲溝槽深度/薄片厚度比爲0.4〜0.6。 又，於薄片面上所描繪之溝槽圖形可爲正三角形或格 子狀或多角型等任一者。若Ni-Zn鐵素體燒結體沿著溝槽 割裂，則重要的是可割裂之單片儘量爲均一單片，即使彎 曲基板也儘量不使導磁率產生變化。 本發明之抑制雜訊薄片由於薄且易割裂故較好至少於 單面上貼合黏著保護薄膜後設置裂縫。 〈作用> 於本發明之要點是本發明之抑制雜訊薄片係藉由控制 導磁率及體積電阻率，而可在微帶線（microstrip line) 之評價中，於1 GHz之反射量控制爲-20dB以下，且吸收 量控制爲25 %以上。 以往，爲了抑制來自電路之雜訊，而使用於樹脂中調 配作爲軟磁性粉末之扁平狀金屬軟磁性粉末並成型爲薄片 φ 狀之抑制雜訊薄片。此抑制雜訊薄片由於含有體積電率低 的金屬粉末，如後述實施例或比較例所示，薄片之體積電 阻率低如1〇3Ωπχ左右，反射亦大。因此，反射訊號與輸入 訊號有干擾的可能性。另一方面，Ni-Zn鐵素體通常爲絕 緣體，由於顯示1〇6Ωηι左右之體積電阻率，故雖然反射量 低，但無法獲得大的吸收量。 因此，爲了獲得反射量低、吸收量大的抑制雜訊薄片 而進行積極探討之結果，發現即使比以往使用之含有扁平 狀金屬軟磁性粉末之抑制雜訊薄片之體積電阻率低也無妨 -17- 201006377 ，亦可獲得反射量低、吸收量高的由Ni-Zn鐵素體所構成 之抑制雜訊薄片。 因此，本發明之抑制雜訊薄片於貼附於電路上時可防 止於10MHz至1GHz中輸入訊號與輸出訊號之干涉，亦可 吸收雜訊。 [實施例] 本發明之代表性實施型態如下。 @ 鐵素體粉末之組成係使用螢光X射線分析裝置RIX 2100(理學電機工業（股）製）測定。 鐵素體粉末之比表面積（BET)係以MONOSOB MS-21 ( YUASA IONICS (股） 製）測定。 抑制雜訊薄片後度係使用微測計（micrometer )測定 〇 抑制雜訊薄片之燒結密度係由自試料外型尺寸所求的 之體積與重量而算出。 @ 抑制雜訊薄片之體積電阻率係於超音波加工機中切出 外徑20mm大小之碟片兩面上塗佈銀糊膏並乾燥後，使用 電阻計354 1 (日置電機（股）製）測定。 抑制雜訊薄片之複導磁率μ’與μ”係於超音波加工機 中切出外徑14mm、內徑8mm的環，使用射頻阻抗分析儀 (RF impedance material analyzer) E499 1 A ( AZILENT 技 術（股）製）測定。 抑制雜訊薄片之反射量及吸收量係以下述方法測定。 -18- 201006377 將製作成寬度40mm、長度50mm之抑制雜訊薄片，以使 抑制雜訊薄片之長度方向對準微帶線長度方向並使各中心 爲一致之方式，裝設於施工有長度100mm、寬度2.3mm、 厚度3 5 μιη之阻抗調整爲5 0Ω之微帶線之基板上。於抑制 雜訊薄片上重疊寬度40mm、長度50mm及厚度10mm之 發泡倍率20〜30倍之發泡聚苯乙烯所構成之板上，以於其 上載置荷重3 00g之狀態，使用與微帶線連接之網路分析 φ 計N523 0A ( AZILENT技術（股）製）測定S參數。自所 得S參數由下式算出反射量[dB]及吸收量[%]。 反射量[dB] = 201og | Sn | 吸收量[%]=(1- I Sh I 2- I S21 丨 2)/lxlOO 抑制雜訊薄片表面粗糙度（中心線平均粗糙度Ra， 最大高度 Rmax )係使用原子間力顯微鏡 AFM ( Nano S cope III，Digital Instrument 公司製），測定 1 0 0 μιη 見方區域而求得。 φ 又，爲表示抑制雜訊薄片表面之凹凸形狀，以相同裝 置之Bearing解析軟體數値化。自求得表面粗糙度之影像 ，求得以其最大高度（Rmax)之50%深度於水平方向之截 斷面之面積佔有率，並比較凹凸形狀狀態。 實施例1 : <Ni-Zn系鐵素體粉末之製造> 以使Ni-Zn系鐵素體之組成成爲特定組成之方式秤取 各氧化物原料，使用磨碎機（attritor)進行濕式混合30 201006377 分鐘後，將混合漿料過濾並乾燥獲得原料混。 料混合粉末於大氣中在900°C暫時燒成i.5小’得 時燒成物以霧化器及振動硏磨機粉碎，獲得Ni_Zn 體粉末。 所得Ni-Zn系鐵素體粉末組成爲？62〇3 = 525莫耳％， NiO = 15.5莫耳％，ΖηΟ = 32·0莫耳％。bet比表面積爲 4.5 m2/g。 <鐵素體成型薄片之製造> 相對於100重量份之所得Ni-Zn系鐵素體粉末，添加 8重量份之作爲結合材料之聚乙烯縮丁醛、3重量份之作 爲可塑劑之苯二甲酸苄酯正丁酯、50重量份之作爲溶劑之 3 -甲基-3-甲氧基-1-丁醇後，充份混合獲得獎料。此獎料 藉由刮刀板式塗佈器，塗佈在單面經噴砂處理成中心線平 均粗糙度（Ra )爲530nm、最大高度（Rmax )爲5.6μιη 之 PET 薄膜 RUMIMAT 50S200 TORRES ( PANAC (股）製 )上，形成塗膜後，藉由乾燥獲得厚度125 μιη之素胚薄片 (green sheet )。所得素胚薄片切斷成寬度4 8mm、長度 6 0mm的大小後，剝離PET薄膜藉此獲得鐵素體成型薄片 <由鐵素體燒結體構成之抑制雜訊薄片之製造> 重疊10片所得鐵素體成型薄片，以氧化鋁片（ Alumina setter )(菊水化學工業（股）製）上下挾持後， 201006377 在5 00 °C脫脂10小時，隨後於空氣中以1 25 0 °C燒成2小時 。冷卻後剝離所得燒結物後，可不使薄片損壞而容易地剝 離。 所得抑制雜訊薄片爲厚度1〇3μηι，寬度40mm，長度 50mm。體積電阻率爲S.SxlC^Qm，燒結密度爲5.15g/cm3 ，於100MHz之μ’爲15，μ”爲72。於10MHz之反射量 爲-36dB，於100MHz之反射量爲-32dB，於500MHz之反 0 射量爲- 33dB，於1GHz之反射量爲-2 7dB，於自10MHz至 1GHz爲止的寬廣頻率範圍爲低的反射量。於10MHz之吸 收量爲3%，於100MHz之吸收量爲10%，於500MHz之吸 收量爲24%，於1 GHz之吸收量爲32%，於自1 0MHz至 I GHz爲止的寬廣頻率範圍爲高的吸收量。 所得抑制雜訊薄片之表面粗糙度爲中心線平均粗糙度 (Ra)爲 345nm，最大高度（Rmax)爲 4.2μιη，於 ΙΟΟμπι 見方之區域內以最大高度之5 0%深度於水平方向截斷面之 φ 面積佔有率爲35%。 實施例2 : 取代經噴砂處理之PET薄膜，而使用未經噴砂處理之 PET薄膜（中心線平均粗糙度（Ra)爲17nm，最大高度 (Rmax)爲0·3μιη ’厚度50μιη)，且逐片燒成鐵素體成 型薄片以外，與實施例1同樣的方法，獲得抑制雜訊薄片 。此時之製造條件及所得之抑制雜訊薄片之諸特性顯示於 表2。如表2所示，與以實施例1之方法所得之抑制雜訊 -21 - 201006377 薄片之特性幾乎無差異。 實施例3 : 除改變鐵素體之組成與BET比表面積以外，以與實施 例1同樣的方法，獲得Ni-Z η系鐵素體粉末。其組成爲 Fe2〇3 = 52.0 莫耳 ％，Ni〇 = 9.8 莫耳 ％，ΖηΟ = 38·2 莫耳 ％。 BET比表面積爲4.9m2/g。 將所得Ni-Zn系鐵素體粉末1〇〇〇重量份以鈦酸酯系 爽 偶合劑KR-TTS (味之素（股）製）10重量份進行表面處 理之Ni-Zn系鐵素體粉末1 000重量份，與熱可塑性彈性 體LUMITAC 22-1 (東曹（股）製）50重量份、密度 0_9g/cm3之聚乙烯1〇〇重量份及硬脂酸20重量份以加壓 捏合機在130 °C混練40分鐘。所得Ni-Zn系鐵素體樹脂混 練物使用噴砂加工成中心線平均粗糙度（Ra)爲650nm， 最大高度（Rmax)爲ΙΟμιη之鐵板，以溫度160°C、壓力 lOOkg/cm2、加壓時間3分鐘進行加壓成型，獲得厚度 馨 58μιη、寬度47mm、長度59mm之鐵素體成型薄片。 重疊1〇片所得鐵素體成型薄片，以氧化鋁片（ Alumina setter)(菊水化學工業（股）製）上下挾持後， 在5 00 °C脫脂1 5小時，隨後於空氣中以丨22〇亡燒成2小時 。冷卻後剝離所得燒結物後，可不使薄片損壞而容易地剝 離。所得抑制雜訊薄片之諸特性顯示於表2。 實施例4 : -22- 201006377 除使用噴砂加工成中心線平均粗糙度（Ra)爲120nm ，最大高度（Rmax)爲2μιη之鐵板且逐片燒成鐵素體成 型薄片以外，與實施例3同樣的方法，獲得抑制雜訊薄片 。此時之製造條件及所得之抑制雜訊薄片之諸特性顯示於 表2。如表2所示，與以實施例3之方法所得之抑制雜訊 薄片之特性幾乎無差異。 φ 實施例5 ' 6 : 除變更鐵素體粉末組成及燒結溫度以外，以與實施例 1同樣方法，獲得抑制雜訊薄片。此時之製造條件及所得 之抑制雜訊薄片之諸特性顯示於表2。 實施例7 : 除變更鐵素體粉末組成及燒結溫度以外，以與實施例 3同樣方法’獲得抑制雜訊薄片。此時之製造條件及所得 〇 之抑制雜訊薄片之諸特性顯示於表2。 比較例1、2 : 取代經噴砂處理之PET薄膜，而使用未經噴砂處理之 PET薄膜（中心線平均粗糙度（Ra )爲1 7nm，最大高度 (Rmax)爲0·3μιη，厚度50μιη)，且變更鐵素體粉末之 組成以外’與實施例1同樣的方法，獲得抑制雜訊薄片。 此時之製造條件及所得之抑制雜訊薄片之諸特性顯示於表 2。又，於比較例1、2中，由於重疊1〇片鐵素體成型薄 -23- 201006377 片燒成時該等固著，故表2中記載其情況逐片燒成之抑制 雜訊薄片之諸特性。 比較例3 : 除使用粗加工成中心線平均粗糖度（Ra)爲252nm， 最大高度（Rmax)爲3.3μηι之PET薄膜U4-50(帝人杜邦 薄膜（股）製）以外，與實施例1同樣的方法，獲得抑制 雜訊薄片。此時之製造條件及所得之抑制雜訊薄片之諸特 性顯示於表2。又，於比較例3中，由於重叠1〇片鐵素體 成型薄片燒成時該等固著，故表2中記載其情況逐片燒成 之抑制雜訊薄片之諸特性。 比較例4、5、6、7 : 除變更鐵素體粉末組成及燒結溫度以外，以與實施例 1同樣方法’獲得抑制雜訊薄片。此時之製造條件及所得 之抑制雜訊薄片之諸特性顯示於表2。 比較例8、9 : 除變更鐵素體粉末組成及燒結溫度以外，以與前述比 較例2同樣方法，獲得抑制雜訊薄片。此時之製造條件及 所得之抑制雜訊薄片之諸特性顯示於表2。 比較例1 0 : 於將苯乙烯系彈性體（密度爲〇.9g/cm3)以20重量％ •201006377 溶解於環己酮中之溶液TF-4200E (日立化成 製）中，以使除去溶劑後體積比成爲扁平狀鐵 金粉末（鐵 '鋁、矽的重量比爲 85:6:9 15〜20，密度爲6_9g/cm3，平均粒徑爲50μιη) ’苯乙烯系彈性體爲53體積％之方式予以計量 獲得漿料。此時，添加用以調整黏度之與彈性 積之乙基環己酮。此漿料以刮刀式塗佈器，塗 φ 處理之PET薄膜（中心線平均粗糙度（Ra：) Μ 大尚度（Rmax)爲 〇.3μιη，厚度 50μιη)上並 塗膜在溫度130°C、壓力90MPa、加壓時間5 成型’獲得韓有ΙΟΟμιη之扁平狀鐵-鋁-矽合 片。 所得薄片諸特性示於表2。體積電阻率爲 ，雖爲本發明範圍之上限値，但爲於500MHz 如-1 0 d B，於5 0 0 Μ Η z之吸收量低如1 2 %者。 ❹ 工業（股） 一銘—砂合 ，縱橫比爲 爲47體積％ ，充份混合 體溶液同體 佈在經噴砂 ^ 1 7nm，最 乾燥。所得 分鐘之條件 金粉末之薄 1.0x1 03Qm 之反射量大 -25- 201006377 [表i] 鐵素體粉末特性 組成 BET[m2/g] Fe2〇3 NiO ZnO 實施例1 52.5 15.5 32.0 4.5 實施例2 52.5 15.5 32.0 4.5 實施例3 52.0 9.8 38.2 4.9 實施例4 52.0 9.8 38.2 4.9 實施例5 51.0 22.1 26.9 3.4 實施例6 56.2 18.7 25.1 5.3 實施例7 53.7 13.1 33.2 6.2 比較例1 50.8 7.8 41.4 4.8 比較例2 57.3 18.1 24.6 3.9 比較例3 51.4 23.4 25.2 5.1 比較例4 51.4 23.4 25.2 5.1 比較例5 58.2 10.0 31.8 4.8 比較例ό 47.9 17.3 34.8 5.0 比較例7 55.7 6.2 38.1 4.5 比較例8 54.5 21.4 24.1 5.2 比較例9 51.1 8.2 40.7 4.9 比較例10 - • •The sintering of the noise suppression sheet of the present invention is preferably carried out industrially by laminating about 5 to 20 sheets of the ferrite formed sheet of the present invention on an alumina plate having a porosity of 30%. The sintering conditions are preferably provided by a process of removing the resin component by using an electric furnace or the like, even if the ferrite particles are grown. The resin removal is carried out at 150 ° C -15 - 201006377 550 ° C for 5 to 80 hours, and the growth of ferrite particles is carried out at 1100 ° C to 1 300 ° C for 1 to 5 hours. When the temperature at the time of growth is less than 1100 ° C, the noise suppression sheet having the required amount of reflection and absorption cannot be obtained. In order to prevent heat deformation or cracking of the sheet, the resin component is preferably removed at a temperature of from room temperature to about 10 to 20 ° C / hour. Further, it is possible to appropriately raise the temperature at 30 to 60 ° C / hour and maintain a constant temperature to sufficiently grow the sintered ferrite particles and then slowly cool them. In addition, the holding temperature of each process © the time of shipment, as long as the optimum conditions are selected according to the number of sheets of ferrite-formed sheets to be processed. The noise suppression sheet of the present invention can be used by providing an adhesive film on at least one surface, adding a crack to the substrate, and imparting flexibility to the laminate. The groove provided in the noise suppression sheet of the present invention can be provided with a front end angle of 25-45 m Z V groove on one side of the formed sheet by an embossing roll or a metal blade. Preferably, the groove spacing is between 1 and 5 mm. If the reference weight is less than 1 mm, the magnetic permeability of the Ni-Zn ferrite sintered body when it is bent along the groove will be lowered, and the processing becomes difficult. If it exceeds 5 mm, the flexibility of the Ni-Zn ferrite sintered body is low. The better spacing of the grooves is 2 to 4 mm. The ratio of the groove depth to the degree of the formed sheet (groove depth/sheet thickness) is 0.4 to 0.7. If the ratio of the groove depth to the thickness of the sheet is less than 〇.4, there is a possibility that the groove cannot be cut along the groove, and the crack will become uneven and the magnetic permeability tends to be unstable. If the ratio of the groove depth to the sheet thickness exceeds 〇.7, it may be cracked along the groove during the firing process. The groove depth is further -16-201006377. The preferred range is the groove depth/sheet thickness ratio of 0.4 to 0.6. Further, the groove pattern drawn on the sheet surface may be an equilateral triangle, a lattice shape or a polygonal shape. If the Ni-Zn ferrite sintered body is split along the groove, it is important that the splittable single piece is as uniform as possible, and the magnetic permeability is not changed as much as possible even if the substrate is bent. Since the noise suppressing sheet of the present invention is thin and easy to be cut, it is preferable to provide a crack after bonding the adhesive protective film to at least one side. <Function> The gist of the present invention is that the noise suppression sheet of the present invention can be controlled at a frequency of 1 GHz in the evaluation of a microstrip line by controlling the magnetic permeability and the volume resistivity. Below -20dB, and the absorption amount is controlled to be 25% or more. Conventionally, in order to suppress noise from a circuit, a flat metal soft magnetic powder as a soft magnetic powder is blended in a resin to form a sheet-like φ-like noise suppression sheet. Since the noise-inhibiting sheet contains a metal powder having a low volume electric power, as shown in Examples or Comparative Examples described later, the sheet has a low volume resistivity of about 1 〇 3 Ω π , and a large reflection. Therefore, there is a possibility that the reflected signal interferes with the input signal. On the other hand, Ni-Zn ferrite is usually an insulator, and since it exhibits a volume resistivity of about 1 〇 6 Ω ηι, although the amount of reflection is low, a large absorption amount cannot be obtained. Therefore, in order to obtain a noise suppression sheet having a low amount of reflection and a large absorption amount, it has been found that the volume resistivity of the noise suppression sheet containing the flat metal soft magnetic powder is lower than that of the conventional one. - 201006377 , it is also possible to obtain a noise suppression sheet composed of Ni-Zn ferrite with low reflection and high absorption. Therefore, the noise suppression sheet of the present invention can prevent the interference of the input signal and the output signal in the 10 MHz to 1 GHz when attached to the circuit, and can also absorb the noise. [Examples] Representative embodiments of the present invention are as follows. The composition of the ferrite powder was measured using a fluorescent X-ray analyzer RIX 2100 (manufactured by Rigaku Corporation). The specific surface area (BET) of the ferrite powder was measured by MONOSOB MS-21 (manufactured by YUASA IONICS Co., Ltd.). The suppression of the noise sheet was measured using a micrometer. 烧结 The suppression of the sintered density of the noise sheet was calculated from the volume and weight of the sample size. The volume resistivity of the noise suppression sheet is measured by cutting the silver paste on both sides of the disk having an outer diameter of 20 mm and drying it in an ultrasonic machine, and then measuring it with a resistance meter 354 1 (manufactured by Hioki Electric Co., Ltd.). The complex magnetic permeability μ' and μ" of the noise suppression sheet are cut out in an ultrasonic machine to cut a ring having an outer diameter of 14 mm and an inner diameter of 8 mm, using an RF impedance material analyzer E499 1 A (AZILENT technology) The measurement of the amount of reflection and the amount of absorption of the noise suppression sheet is measured by the following method: -18- 201006377 A noise suppression sheet having a width of 40 mm and a length of 50 mm is formed so as to suppress the length direction of the noise sheet. The microstrip line has a length direction and the centers are uniform, and is mounted on a substrate having a microstrip line having a length of 100 mm, a width of 2.3 mm, and a thickness of 35 μm adjusted to 50 Ω. A plate made of expanded polystyrene having a width of 40 mm, a length of 50 mm, and a thickness of 10 mm and a foaming ratio of 20 to 30 times is used, and a network analysis connected to the microstrip line is used in a state where a load of 300 g is placed thereon. φ meter N523 0A (AZILENT technology system) measures the S parameter. From the obtained S parameter, the reflection amount [dB] and the absorption amount [%] are calculated from the following equation: Reflectance [dB] = 201og | Sn | Absorption [%] ]=(1- I Sh I 2- I S21 丨2)/lxlOO The surface roughness (center line average roughness Ra, maximum height Rmax) of the noise suppression sheet was determined by using an atomic force microscope AFM (Nano S cope III, manufactured by Digital Instrument Co., Ltd.) to measure a 100 μm square region. In addition, in order to suppress the uneven shape of the surface of the noise sheet, the number of the analysis software of the same device is reduced. From the image of the surface roughness, the depth of the maximum height (Rmax) is 50% and the horizontal direction is cut off. The area ratio of the surface was compared with the state of the uneven shape. Example 1: <Production of Ni-Zn-based ferrite powder> Each oxidation was measured in such a manner that the composition of the Ni-Zn-based ferrite became a specific composition. Raw material, wet mixing with an attritor 30 201006377 minutes, the mixed slurry is filtered and dried to obtain a raw material mixture. The mixed powder is temporarily fired at 900 ° C in the atmosphere i.5 small 'time The fired product was pulverized by an atomizer and a vibration honing machine to obtain a Ni_Zn bulk powder. The composition of the obtained Ni-Zn ferrite powder was ?62〇3 = 525 mol%, NiO = 15.5 mol%, ΖηΟ = 32 ·0 mole% The specific surface area of the bet is 4.5 m 2 /g. <Production of ferrite-formed sheet> 8 parts by weight of polyvinyl butyral as a binding material is added with respect to 100 parts by weight of the obtained Ni-Zn-based ferrite powder After 3 parts by weight of benzyl butyl methacrylate as a plasticizer and 50 parts by weight of 3-methyl-3-methoxy-1-butanol as a solvent, the mixture was mixed to obtain a prize. This prize was coated on a single-sided blast-coated PET film RUMIMAT 50S200 TORRES (PANAC) with a center line average roughness (Ra) of 530 nm and a maximum height (Rmax) of 5.6 μm by a doctor blade applicator. On the basis of the formation of a coating film, a green sheet having a thickness of 125 μm was obtained by drying. After the obtained prime embryonic sheet was cut into a width of 48 mm and a length of 60 mm, the PET film was peeled off to obtain a ferrite formed sheet. <Manufacture of a noise suppressing sheet composed of a ferrite sintered body>> Overlapping 10 pieces The obtained ferrite-formed sheet was held up and down by an Alumina setter (manufactured by Kikusui Chemical Industry Co., Ltd.), degreased at 20100377 for 10 hours at 500 ° C, and then fired at 1500 ° C in air. 2 hours. After the obtained sintered product is peeled off after cooling, the sheet can be easily peeled off without damaging the sheet. The resulting noise suppression sheet had a thickness of 1 〇 3 μηι, a width of 40 mm, and a length of 50 mm. The volume resistivity is S.SxlC^Qm, the sintered density is 5.15g/cm3, the μ' at 100MHz is 15, and the μ is 72. The reflection at 10MHz is -36dB, and the reflection at 100MHz is -32dB. The 500MHz inverse zero is -33dB, the reflection at 1GHz is -27dB, and the wide frequency range from 10MHz to 1GHz is low. The absorption at 10MHz is 3%, and the absorption at 100MHz. It is 10%, the absorption at 500MHz is 24%, the absorption at 1 GHz is 32%, and the absorption in the wide frequency range from 10 MHz to I GHz is high. The surface roughness of the resulting noise suppression sheet is obtained. The center line has an average roughness (Ra) of 345 nm and a maximum height (Rmax) of 4.2 μm. In the region of ΙΟΟμπι square, the area of the φ area in the horizontal direction at a depth of 50% of the maximum height is 35%. Example 2: Instead of a sandblasted PET film, a non-blasted PET film (center line average roughness (Ra) of 17 nm, maximum height (Rmax) of 0·3 μιη 'thickness 50 μιη) was burned piece by piece. In the same manner as in Example 1, except for forming a ferrite-formed sheet, suppression was obtained. The sheet processing conditions at this time and the characteristics of the obtained noise suppression sheet are shown in Table 2. As shown in Table 2, the characteristics of the sheet of the noise suppression-21 - 201006377 obtained by the method of Example 1 were almost absent. Example 3: Ni-Z η-based ferrite powder was obtained in the same manner as in Example 1 except that the composition of the ferrite and the BET specific surface area were changed. The composition was Fe2〇3 = 52.0 mol%. Ni〇= 9.8 Mohr%, ΖηΟ = 38·2 Mohr %. The BET specific surface area is 4.9 m 2 /g. The obtained Ni-Zn ferrite powder is 1 part by weight to the titanate type Mixture KR-TTS (manufactured by Ajinomoto Co., Ltd.) 10 parts by weight of surface-treated Ni-Zn ferrite powder 1 000 parts by weight, and thermoplastic elastomer LUMITAC 22-1 (manufactured by Tosoh Corporation) 50 parts by weight, 1 part by weight of polyethylene having a density of 0-9 g/cm3, and 20 parts by weight of stearic acid were kneaded by a pressure kneader at 130 ° C for 40 minutes. The obtained Ni-Zn-based ferritic resin kneaded material was sandblasted. The center line has an average roughness (Ra) of 650 nm and a maximum height (Rmax) of ΙΟμιη iron plate at a temperature of 160°. C, pressure lOOkg / cm2, pressurization time 3 minutes for pressure molding, to obtain a ferrite-molded sheet having a thickness of 58 μm, a width of 47 mm, and a length of 59 mm. The ferrite-molded sheet obtained by overlapping one sheet of the sheet was made of alumina sheet ( Alumina setter (manufactured by Kikusui Chemical Industry Co., Ltd.) was degreased at 500 ° C for 15 hours, then burned in air for 22 hours. After the obtained sintered product is peeled off after cooling, the sheet can be easily peeled off without damaging the sheet. The characteristics of the resulting noise suppression sheet are shown in Table 2. Example 4: -22-201006377 In addition to the use of sandblasting into an iron plate having a center line average roughness (Ra) of 120 nm and a maximum height (Rmax) of 2 μm, and firing a ferrite-formed sheet by piece, and Example 3 In the same way, a noise suppression sheet is obtained. The manufacturing conditions at this time and the characteristics of the resulting noise suppression sheet are shown in Table 2. As shown in Table 2, there was almost no difference from the characteristics of the noise suppression sheet obtained by the method of Example 3. φ Example 5 '6 : A noise suppression sheet was obtained in the same manner as in Example 1 except that the composition of the ferrite powder and the sintering temperature were changed. The manufacturing conditions at this time and the characteristics of the resulting noise suppression sheet are shown in Table 2. Example 7: A noise suppression sheet was obtained in the same manner as in Example 3 except that the composition of the ferrite powder and the sintering temperature were changed. The manufacturing conditions at this time and the characteristics of the obtained noise suppression sheet are shown in Table 2. Comparative Examples 1 and 2: Instead of the sandblasted PET film, a PET film which was not blasted (center line average roughness (Ra) of 17 nm, maximum height (Rmax) of 0.3 μm, thickness of 50 μm), In addition to the composition of the ferrite powder, the same method as in Example 1 was carried out to obtain a noise suppression sheet. The manufacturing conditions at this time and the characteristics of the obtained noise suppression sheet are shown in Table 2. Further, in Comparative Examples 1 and 2, since the overlap of the one-sheet ferrite-molded thin -23-201006377 sheet was fixed at the time of firing, the table 2 described the case where the noise-reducing sheet was fired piece by piece. Various characteristics. Comparative Example 3: The same procedure as in Example 1 except that PET film U4-50 (manufactured by Teijin DuPont Film Co., Ltd.) having a coarseness (Ra) of 252 nm and a maximum height (Rmax) of 3.3 μm was used. The method of obtaining a noise suppression sheet. The manufacturing conditions at this time and the characteristics of the obtained noise suppression sheet are shown in Table 2. Further, in Comparative Example 3, since the first one of the bismuth ferrite-molded sheets was fixed at the time of firing, the characteristics of the noise-suppressing sheets which were fired piece by piece in Table 2 were described. Comparative Examples 4, 5, 6, and 7: Noise suppression sheets were obtained in the same manner as in Example 1 except that the composition of the ferrite powder and the sintering temperature were changed. The manufacturing conditions at this time and the characteristics of the resulting noise suppression sheet are shown in Table 2. Comparative Examples 8 and 9: In addition to changing the composition of the ferrite powder and the sintering temperature, a noise suppression sheet was obtained in the same manner as in the above Comparative Example 2. The manufacturing conditions at this time and the characteristics of the resulting noise suppression sheet are shown in Table 2. Comparative Example 1 0 : A solution of styrene-based elastomer (density: 9.9 g/cm 3 ) in 20% by weight of 201006377 dissolved in cyclohexanone TF-4200E (manufactured by Hitachi Chemical Co., Ltd.) was used to remove the solvent. The volume ratio is a flat iron powder (the weight ratio of iron 'aluminum to tantalum is 85:6:9 15 to 20, the density is 6-9 g/cm 3 , and the average particle diameter is 50 μm). The styrene elastomer is 53% by volume. The method is to measure the slurry. At this time, ethylcyclohexanone for adjusting the viscosity and the elastic product was added. This slurry was coated with a φ-treated PET film (center line average roughness (Ra:) Μ (Rmax) of 〇.3 μιη, thickness 50 μιη) with a knife coater and coated at a temperature of 130 ° C. , pressure 90MPa, pressurization time 5 molding 'obtained Han-style ΙΟΟμιη flat iron-aluminum-矽 piece. The properties of the obtained flakes are shown in Table 2. The volume resistivity, which is the upper limit of the range of the present invention, is such that at 500 MHz, for example, -1 0 d B, the absorption at 500 Μ Η z is as low as 12%. ❹ Industry (shares) Yiming—sanding, the aspect ratio is 47% by volume, and the mixture of the mixed solution is sprayed with sand at a distance of 17 nm, which is the most dry. The obtained minute condition gold powder thin 1.0x1 03Qm reflection amount is large -25-201006377 [Table i] Ferrite powder characteristic composition BET[m2/g] Fe2〇3 NiO ZnO Example 1 52.5 15.5 32.0 4.5 Example 2 52.5 15.5 32.0 4.5 Example 3 52.0 9.8 38.2 4.9 Example 4 52.0 9.8 38.2 4.9 Example 5 51.0 22.1 26.9 3.4 Example 6 56.2 18.7 25.1 5.3 Example 7 53.7 13.1 33.2 6.2 Comparative Example 1 50.8 7.8 41.4 4.8 Comparative Example 2 57.3 18.1 24.6 3.9 Comparative Example 3 51.4 23.4 25.2 5.1 Comparative Example 4 51.4 23.4 25.2 5.1 Comparative Example 5 58.2 10.0 31.8 4.8 Comparative Example 7.9 47.9 17.3 34.8 5.0 Comparative Example 7 55.7 6.2 38.1 4.5 Comparative Example 8 54.5 21.4 24.1 5.2 Comparative Example 9 51.1 8.2 40.7 4.9 Comparative Example 10 - • •
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抑制雜訊薄片之特性 固著 狀況 無固著1 垂 無固著1 > 無固著 無固著 無固著 有固著] i有固著1 有固著Ί 無固著 無固著 無固著1 無固著1 R固著1 1有固著1 • Bearing 解析數據 | £ 的 1ΠΕ N S 英iB | Μ 〇〇 (S CS μ <N Os KT) (N <N ο 00 〇〇 <N s〇 (N Os (S <N 寸 1 表面粗糙度 Rmax 1 ["m] (N — P 00 in (N <N rn irj (N Γ ΟΟ ίΝ 〇\ 卜 (N m (N m ITi r-i ON 卜 rn 1 <§ I •Ti s 454 v〇 278 S 642 v〇 \〇 v> 1 〇0 334 沄 ON m IT： ο m « 吸收量[%] 1 1 GHz (S ON m m m ?： S s rs oo Os fS ΓΛ fN 500 ! MHz 艺 m <N VJ m *Ti 00 CN 00 (Ν <N <N p*·» CN = oo = fS Γ|4 100 i MHz o Os v〇 so = 卜 二 <N <N (N (N iS <N cn \η 10 i MHz m »r> V» m (N r*> — 一 — - — — — — — 反射量[册] 1 i GHz 卜 <N oo (N 〇\ rs 00 <N 啤 ίΝ 〇 rn 〇 rn 00 <N 〇0 <N r^i 〇 <N o ο rn m 500 ;MHz m 〇 pn 兮 rn 对 ΓΟ 〇\ (N m fS cn m rn <N rn 〇\ fS o PO m r^i tJ- rn rn (N m rn Ο 100 MHz (N m o m m m rn ON rs S Vi fO c<p V*) r^j cn rn w> fn rf C^l m m 〇\ I 10 i MHz s〇 fn Ό rn 卜 rn r- rn CN rn (N 00 rn oo P： 兮 rn r^> oo m so rn V) rn Ό rn «Τί ΓΟ Os cn 1 在 100MHz 之複磁導率 (N 〇 ro oo m 00 S Vi (N 艺 00 (N - v〇 (N 〇\ 卜 =1 tn Ό KT> 00 <N 卜 m Os 卜 寸 卜 w~> fS 體積 電阻率 [Qm] 5.5x10* 5.6x10' 1.3xl02 1.3xl02 9.7x10° 1.8x10° 7.3xl02 3.5xl03 I 2.4xl03 -1 3.3x10' 1 3.2x10' | 6.1xl04 4.5xl06 1.7xl02 9.8x1ο1 2.5x10' l.OxlO3 燒結 密度 [g/cm3] iri 5.15 tn wi 5.13 5.22 5.12 4.97 m wi 5.19 m 5.11 | 5.02 卜 νϊ 5.15 5.14 厚度 _ s 守 m (N 239 V〇 00 P； 355 § 450 W) CM § 00 Os s 444 <Ν tn 对 1燒結 溫度 rc] 1250 1250 1220 1220 1290 1200 1100 1220 1280 1200 1220 1230 1270 1250 1250 1230 實施例1 實施例2 實施例3 實施例4 實施例5 實施例6 實施例7 比較例1 比較例2 比較例3 比較例4 I 比較例5 比較例6 比較例7 比較例8 比較例9 ： 比較例10 -27- 201006377 本發明之抑制雜訊薄片於10MHz、100MHz、500MHz 及1GHz反射量均爲-20dB以下，自10MHz至1GHz之廣 頻率範圍內爲低的反射量。又，於10MHz之吸收量爲2% 以上，於100MHz之吸收量爲6%以上，於500MHz之吸收 量爲 20%以上，於 1 GHz之吸收量爲25%以上，確認自 10MHz至1 GHz之廣頻率範圍內爲高的吸收量。因此，本 發明之抑制雜訊薄片於自10MHz至1GHz之廣頻率範圍內 之反射量低，吸收量高，故確認可使用作爲抑制雜訊薄片Suppresses the characteristics of the noise sheet. The fixation condition is not fixed. 1 垂 无 fixation 1 > No fixation, no fixation, no fixation, fixation, fixation, fixation, fixation, fixation, fixation, fixation, fixation, fixation, fixation 1 固定 fixation 1 R fixation 1 1 fixation 1 • Bearing analysis data | £ 1 ΠΕ NS 英 iB | Μ 〇〇 (S CS μ <N Os KT) (N <N ο 00 〇〇< ;N s〇(N Os (S <N inch 1 surface roughness Rmax 1 ["m] (N — P 00 in (N <N rn irj (N Γ ΟΟ Ν Ν 〇 N (N m (N m ITi ri ON 卜 1 <§ I •Ti s 454 v〇278 S 642 v〇\〇v> 1 〇0 334 沄ON m IT: ο m « Absorption [%] 1 1 GHz (S ON mmm ?: S s rs oo Os fS ΓΛ fN 500 ! MHz 艺 m <N VJ m *Ti 00 CN 00 (Ν <N <N p*·» CN = oo = fS Γ|4 100 i MHz o Os V〇so = 卜二<N <N (N (N iS <N cn \η 10 i MHz m »r> V» m (N r*> — one — — — — — — — reflection amount [Book] 1 i GHz 卜<N oo (N 〇\ rs 00 <N 啤酒 Ν 〇rn 〇rn 00 <N 〇0 <N r^i 〇<N o ο rn m 500 ;MHz m 〇pn 兮rn confrontation Ο 〇\ (N m fS cn m rn <N rn 〇\ fS o PO mr^i tJ- rn rn (N m rn Ο 100 MHz (N mommm rn ON rs S Vi fO c<p V*) r^ j cn rn w> fn rf C^lmm 〇\ I 10 i MHz s〇fn Ό rn rn r- rn CN rn (N 00 rn oo P: 兮rn r^> oo m so rn V) rn Ό rn «Τί ΓΟ Os cn 1 Complex permeability at 100MHz (N 〇ro oo m 00 S Vi (N 00 00 (N 〇 00 N =1 t t t t t t t t t t O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O Inch w~> fS volume resistivity [Qm] 5.5x10* 5.6x10' 1.3xl02 1.3xl02 9.7x10° 1.8x10° 7.3xl02 3.5xl03 I 2.4xl03 -1 3.3x10' 1 3.2x10' | 6.1xl04 4.5xl06 1.7xl02 9.8x1ο1 2.5x10' l.OxlO3 Sintering density [g/cm3] iri 5.15 tn wi 5.13 5.22 5.12 4.97 m wi 5.19 m 5.11 | 5.02 卜νϊ 5.15 5.14 thickness _ s m (N 239 V〇00 P; 355 § 450 W) CM § 00 Os s 444 < Ν tn to 1 sintering temperature rc] 1250 1250 1220 1220 1290 1200 1100 1220 1280 1200 1220 1230 1270 1250 1250 1230 Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Comparative Example 1 Comparative Example 2 Comparison 3 Comparative Example 4 I Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 Comparative Example 9: Comparative Example 10 -27- 201006377 The noise suppression sheet of the present invention has a reflection amount of -20 dB or less at 10 MHz, 100 MHz, 500 MHz, and 1 GHz. , a low amount of reflection in a wide frequency range from 10 MHz to 1 GHz. In addition, the absorption at 10 MHz is 2% or more, the absorption at 100 MHz is 6% or more, the absorption at 500 MHz is 20% or more, and the absorption at 1 GHz is 25% or more, and it is confirmed from 10 MHz to 1 GHz. High absorption in a wide frequency range. Therefore, the noise suppression sheet of the present invention has a low reflection amount in a wide frequency range from 10 MHz to 1 GHz and a high absorption amount, so that it can be used as a noise suppression sheet.
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