JPH0967141A - Glass material having coercive force - Google Patents
Glass material having coercive forceInfo
- Publication number
- JPH0967141A JPH0967141A JP24084595A JP24084595A JPH0967141A JP H0967141 A JPH0967141 A JP H0967141A JP 24084595 A JP24084595 A JP 24084595A JP 24084595 A JP24084595 A JP 24084595A JP H0967141 A JPH0967141 A JP H0967141A
- Authority
- JP
- Japan
- Prior art keywords
- glass
- coercive force
- glass material
- fine particles
- magnetic fine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F10/00—Thin magnetic films, e.g. of one-domain structure
- H01F10/08—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers
- H01F10/10—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition
- H01F10/12—Thin magnetic films, e.g. of one-domain structure characterised by magnetic layers characterised by the composition being metals or alloys
- H01F10/13—Amorphous metallic alloys, e.g. glassy metals
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C14/00—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix
- C03C14/004—Glass compositions containing a non-glass component, e.g. compositions containing fibres, filaments, whiskers, platelets, or the like, dispersed in a glass matrix the non-glass component being in the form of particles or flakes
-
- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2214/00—Nature of the non-vitreous component
- C03C2214/30—Methods of making the composites
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、保磁力と可視域に
おける透光性とを兼ね備えたガラス材料に関する。The present invention relates to a glass material having both coercive force and translucency in the visible region.
【０００２】[0002]
【従来の技術】磁性体微粒子は、ほぼ単磁区を構成する
数十ｎｍ程度の微粒子の状態では、保磁力が著しく増大
する。磁性体微粒子が凝集した粉体については、保磁力
に関する多くの研究例があるが、磁性体微粒子を安定な
マトリックス中に分散させた材料の磁気的性質に関する
研究例は、ほとんどない。2. Description of the Related Art In the case of magnetic fine particles in the state of fine particles of about several tens of nm constituting substantially a single magnetic domain, the coercive force is significantly increased. There are many examples of research on coercive force with respect to powder in which magnetic fine particles are aggregated, but there are few research examples on magnetic properties of a material in which magnetic fine particles are dispersed in a stable matrix.
【０００３】例えば、高い保磁力を有する磁性体微粒子
を可視域で透明なガラス材料に均一に分散させることが
できれば、高い保磁力を有し、且つ透明なガラス材料が
できる可能性がある。For example, if magnetic fine particles having a high coercive force can be uniformly dispersed in a transparent glass material in the visible region, a transparent glass material having a high coercive force may be produced.
【０００４】[0004]
【発明が解決しようとする課題】従って、本発明は、保
磁力と透光性の両方を兼ね備えたガラス材料を提供する
ことを主な目的とする。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a glass material having both coercive force and translucency.
【０００５】[0005]
【課題を解決するための手段】本発明者は、鋭意研究を
重ねた結果、磁性体微粒子形成成分と透明ガラス成分と
を用いて高周波スパッタリング法を行う場合には、高い
保磁力を有し且つ透明なガラス材料が得られることを見
出した。As a result of intensive studies, the present inventor has found that when a high-frequency sputtering method is performed using a magnetic fine particle forming component and a transparent glass component, a high coercive force is obtained. It has been found that a transparent glass material can be obtained.
【０００６】すなわち、本発明は、下記のガラス材料お
よびその製造方法を提供するものである： １．磁性体微粒子を分散含有しており、高い保磁力を有
し且つ可視域において透光性をもつガラス材料。That is, the present invention provides the following glass materials and a method for producing the same: A glass material that contains magnetic fine particles in a dispersed manner, has a high coercive force, and has a light-transmitting property in the visible region.
【０００７】２．磁性体微粒子がα−Ｆｅであり、該微
粒子を分散せしめるガラス材料がシリカガラスである上
記項１に記載のガラス材料。[0007] 2. Item 2. The glass material according to item 1, wherein the magnetic fine particles are α-Fe, and the glass material in which the fine particles are dispersed is silica glass.
【０００８】３．磁性体微粒子形成成分と透明ガラス成
分とを用いて高周波スパッタリング法により磁性体微粒
子を含有する透明ガラス材料を作製する方法。[0008] 3. A method of producing a transparent glass material containing magnetic fine particles by high frequency sputtering using a magnetic fine particle forming component and a transparent glass component.
【０００９】４．磁性体微粒子形成成分が鉄であり、ガ
ラス成分がシリカガラスである上記項３に記載の方法。4. Item 4. The method according to Item 3, wherein the magnetic fine particle forming component is iron, and the glass component is silica glass.
【００１０】５．高周波スパッタリングを行う際のガス
がアルゴンを主成分とする上記項３または４に記載の方
法。5. Item 5. The method according to Item 3 or 4, wherein the gas used for high-frequency sputtering is mainly composed of argon.
【００１１】６．上記項３乃至５のいずれかの方法で得
られた磁性体微粒子分散含有する透明ガラスをさらに温
度６５０〜７００℃の範囲で熱処理することを特徴とす
る保磁力を改善した透明ガラス材料。6. Item 7. A transparent glass material having improved coercive force, wherein the transparent glass containing the magnetic fine particles dispersed therein obtained by any one of the above items 3 to 5 is further heat-treated at a temperature of 650 to 700 ° C.
【００１２】[0012]
【発明の実施の形態】本発明のガラス材料における強磁
性体微粒子としては、特に限定されるものではないが、
原料として安価な鉄を使用することにより形成できるα
-Ｆｅ微粒子が好ましい。BEST MODE FOR CARRYING OUT THE INVENTION The ferromagnetic fine particles in the glass material of the present invention are not particularly limited,
Α that can be formed by using inexpensive iron as a raw material
-Fe fine particles are preferred.
【００１３】また、可視域において透光性をもつガラス
材料についても、特に限定されるものではないが、例え
ば、シリカガラスがあげられる。本発明において、「可
視域において透光性をもつガラス」とは、可視域でファ
ラデー効果を利用できることを意味する。The glass material having a light-transmitting property in the visible region is not particularly limited, and examples thereof include silica glass. In the present invention, "glass having translucency in the visible region" means that the Faraday effect can be used in the visible region.
【００１４】α−Ｆｅ微粒子の粒径は、通常６〜１５ｎ
ｍ程度であり、より好ましくは１５ｎｍ程度である。The particle size of the α-Fe fine particles is usually 6 to 15 n.
m, more preferably about 15 nm.
【００１５】α−Ｆｅ微粒子分散シリカガラスの製造方
法としては、アルゴンガスなどの不活性ガス中で高周波
スパッタリング法によって鉄とシリカガラスとを同時ス
パッタして、ガラスなどの基板上にα−Ｆｅ含有シリカ
ガラスを析出させる方法が好ましい。例えば、同じ原料
を用いて通常の溶融法によって鉄−シリカガラスを製造
する場合には、Ｆｅの大半がイオンとしてガラス中に溶
解するので、α−Ｆｅ微粒子は殆ど形成されない。高周
波スパッタリング法は、常法により行うことができ、そ
の条件などは限定されないが、通常１０-2torr〜１０-3
torr程度の圧力下で数十Ｗ〜数百Ｗ程度の出力で行う。As a method for producing α-Fe fine particle-dispersed silica glass, iron and silica glass are simultaneously sputtered by a high-frequency sputtering method in an inert gas such as argon gas, and α-Fe-containing A method of precipitating silica glass is preferred. For example, when iron-silica glass is produced using the same raw material by a normal melting method, most of Fe dissolves in the glass as ions, so that almost no α-Fe fine particles are formed. The high-frequency sputtering method can be performed by a conventional method, and the conditions and the like are not limited, but usually 10 −2 torr to 10 −3.
The operation is performed under a pressure of about torr and an output of about several tens W to several hundred W.
【００１６】ここで、ＳｉＯ2に対するＦｅの含有割合
をＦｅ／Ｓｉモル比で表すと、Ｆｅ／Ｓｉ＝１５〜２０
％程度の領域が好ましく、Ｆｅ／Ｓｉ＝２０程度がより
好ましい。Ｆｅの量が少なすぎる場合には、α−Ｆｅ微
粒子が十分に析出いないのに対し、多すぎる場合には、
ガラスの透光性が失われる傾向がある。Here, when the content ratio of Fe to SiO 2 is represented by a molar ratio of Fe / Si, Fe / Si = 15 to 20
% Is preferable, and Fe / Si = 20 is more preferable. When the amount of Fe is too small, α-Fe fine particles are not sufficiently precipitated, while when it is too large,
The translucency of the glass tends to be lost.
【００１７】本発明方法により得られた鉄微粒子分散ガ
ラス材料を空気中で熱処理すると、α−Ｆｅがより効率
よくガラス中に析出するので、ガラス材料の保磁力がよ
り一層改善される。熱処理温度は、通常６３０〜７２０
℃程度であり、より好ましくは６５０〜７００℃程度で
ある。熱処理温度が低すぎる場合には、鉄微粒子が十分
に成長しないため保磁力が小さくなるのに対し、高すぎ
る場合には、常磁性であるＦｅ2Ｏ3微粒子が析出すると
いう欠点がある。When the iron fine particle-dispersed glass material obtained by the method of the present invention is heat-treated in air, α-Fe is more efficiently precipitated in the glass, so that the coercive force of the glass material is further improved. The heat treatment temperature is usually 630 to 720
C., and more preferably about 650-700.degree. When the heat treatment temperature is too low, the coercive force is reduced because the iron fine particles do not grow sufficiently. On the other hand, when the heat treatment temperature is too high, paramagnetic Fe 2 O 3 fine particles are precipitated.
【００１８】[0018]
【実施例】以下、本発明を実施例に基づいてさらに詳し
く説明する。EXAMPLES The present invention will be described in more detail based on the following examples.
【００１９】実施例１ 雰囲気ガス＝Ａｒ、流量＝２ｃｃ／分、チャンバー内圧
力＝１０-2torrの条件下にて、Ｆｅ／Ｓｉモル比が１８
％である鉄−シリカガラス混合材料を高周波スパッタリ
ング法によりスパッタして、約１．７ｎｍ／分の速度で
約１２０分間シリカガラス基板上に堆積させた。Example 1 Under the conditions of an atmosphere gas = Ar, a flow rate = 2 cc / min, and a chamber pressure = 10 −2 torr, the Fe / Si molar ratio was 18
% Of an iron-silica glass mixed material was sputtered by a high frequency sputtering method and deposited on a silica glass substrate at a rate of about 1.7 nm / min for about 120 minutes.
【００２０】得られた薄膜材料の組成は、ＸＰＳによっ
て目的どおりに調整されていることを確認した。It was confirmed that the composition of the obtained thin film material was adjusted as intended by XPS.
【００２１】次いで、得られた薄膜材料を温度７００℃
の空気中で９０分間熱処理したところ、図１に示す様に
α−ＦｅによるＸ線回折ピークが明瞭に観測された。ま
た、この薄膜材料を透過電子顕微鏡により観察したとこ
ろ、該鉄微粒子の平均粒径は１５ｎｍ程度であることが
確認された。Next, the obtained thin film material is heated to a temperature of 700 ° C.
As a result, the X-ray diffraction peak due to α-Fe was clearly observed as shown in FIG. When the thin film material was observed with a transmission electron microscope, it was confirmed that the average particle size of the iron fine particles was about 15 nm.
【００２２】また、この材料の保磁力を測定したとこ
ろ、図２に示す様に３５エルステッドであり、α−Ｆｅ
単体の保磁力の３０倍以上であることが確認された。When the coercive force of this material was measured, it was 35 Oe as shown in FIG.
It was confirmed that the coercive force was at least 30 times the coercive force of a single substance.
【００２３】実施例２ 実施例１と同様なスパッタ条件で得られた薄膜を７００
℃大気中で３０分熱処理したところ実施例−１と同様に
α−ＦｅのＸ線回折ピークが明瞭に観測され、保磁力は
３０エルステッドと大きな値を示した。Example 2 A thin film obtained under the same sputtering conditions as in Example 1 was 700
When heat treatment was performed in the air at 30 ° C. for 30 minutes, the X-ray diffraction peak of α-Fe was clearly observed as in Example 1, and the coercive force showed a large value of 30 Oe.
【００２４】実施例３ Ｆｅ／Ｓｉモル比が２０％である鉄−シリカガラス混合
材料を使用する以外は実施例１と同様にして膜厚０．６
μｍのα−Ｆｅ微粒子含有シリカガラス薄膜を得た。Example 3 A film thickness of 0.6 was obtained in the same manner as in Example 1 except that an iron-silica glass mixed material having an Fe / Si molar ratio of 20% was used.
A μm-containing α-Fe fine particle-containing silica glass thin film was obtained.
【００２５】得られた薄膜の製造直後の磁化曲線と大気
中６５０℃で３０分間熱処理した場合の磁化曲線とを図
３に示す。熱処理により、薄膜の磁化の絶対値が著しく
上昇していることが明らかである。FIG. 3 shows a magnetization curve obtained immediately after the production of the obtained thin film and a magnetization curve obtained by heat-treating at 650 ° C. for 30 minutes in the atmosphere. It is clear that the heat treatment significantly increases the absolute value of the magnetization of the thin film.
【００２６】熱処理後の薄膜中には、薄膜Ｘ線回折によ
り、粒子径６ｎｍ程度のα−Ｆｅまたはその固溶体の結
晶が存在することが確認された。In the thin film after the heat treatment, it was confirmed by thin film X-ray diffraction that crystals of α-Fe or a solid solution thereof having a particle diameter of about 6 nm were present.
【００２７】比較例１ Ｆｅ／Ｓｉ比が８％である鉄−シリカガラス混合材料を
実施例１と同様なスパッタ条件でスパッタし、得られた
薄膜材料を６５０℃で３０分熱処理したところα−Ｆｅ
による回折ピークは認められず、保磁力も測定不可能な
ほど小さかった。Comparative Example 1 An iron-silica glass mixed material having an Fe / Si ratio of 8% was sputtered under the same sputtering conditions as in Example 1, and the obtained thin film material was heat-treated at 650 ° C. for 30 minutes. Fe
No diffraction peak was observed, and the coercive force was too small to be measured.
【００２８】比較例２ Ｆｅ／Ｓｉ比が２１％の組成からなる薄膜材料を実施例
１と同様なスパッタ条件にて作製し、６５０℃で３０分
熱処理したところ、α−Ｆｅによる回折が確認された
が、同時にＦｅ2ＳｉＯ4、Ｆｅ2Ｏ3による強いピークも
みられた。また、薄膜はやや金属光沢を帯びており、そ
のため透過率の低下が見られた。Comparative Example 2 A thin film material having a composition having an Fe / Si ratio of 21% was prepared under the same sputtering conditions as in Example 1 and heat-treated at 650 ° C. for 30 minutes. As a result, diffraction by α-Fe was confirmed. However, at the same time, strong peaks due to Fe 2 SiO 4 and Fe 2 O 3 were also observed. In addition, the thin film had a slightly metallic luster, and a decrease in transmittance was observed.
【００２９】[0029]
【発明の効果】本発明によれば、高周波スパッタリング
法を用いることにより、従来にない高い保磁力を有し、
かつ透光性をも兼ね備えたα−Ｆｅ微粒子分散ガラスを
容易に得ることができる。According to the present invention, by using a high frequency sputtering method, a high coercive force, which has not been achieved in the past, is obtained.
Further, it is possible to easily obtain α-Fe fine particle-dispersed glass which also has a light transmitting property.
【００３０】本発明による高い保磁力と透明性とを兼ね
備えた新規なガラス材料は、ファラデー効果を利用した
光磁気記録材料などとして有用である。The novel glass material having both high coercive force and transparency according to the present invention is useful as a magneto-optical recording material utilizing the Faraday effect.
【図１】実施例１により得られたα−Ｆｅ微粒子分散シ
リカガラス薄膜材料の熱処理後のＸ線回折結果を示すチ
ャートである。FIG. 1 is a chart showing the results of X-ray diffraction after heat treatment of a silica glass thin film material with α-Fe fine particles dispersed therein obtained in Example 1.
【図２】実施例１により得られたα−Ｆｅ微粒子分散シ
リカガラス薄膜材料の熱処理後の減磁曲線を示すグラフ
である。FIG. 2 is a graph showing a demagnetization curve after heat treatment of the α-Fe fine particle-dispersed silica glass thin film material obtained in Example 1.
【図３】実施例３で得られた薄膜材料の製造直後の磁化
曲線と大気中６５０℃で３０分間熱処理した場合の磁化
曲線とを示すグラフである。FIG. 3 is a graph showing a magnetization curve immediately after the production of the thin film material obtained in Example 3 and a magnetization curve when heat-treated at 650 ° C. for 30 minutes in the atmosphere.
Claims (6)
磁力を有し且つ可視域において透光性をもつガラス材
料。1. A glass material containing magnetic fine particles dispersed therein, having a high coercive force and transmitting light in the visible region.
を分散せしめるガラス材料がシリカガラスである請求項
１に記載のガラス材料。2. The glass material according to claim 1, wherein the magnetic fine particles are α-Fe, and the glass material in which the fine particles are dispersed is silica glass.
を用いて高周波スパッタリング法により磁性体微粒子を
含有する透明ガラス材料を作製する方法。3. A method for producing a transparent glass material containing magnetic fine particles by a high frequency sputtering method using a magnetic fine particle forming component and a transparent glass component.
成分がシリカガラスである請求項３に記載の方法。4. The method according to claim 3, wherein the magnetic fine particle forming component is iron and the glass component is silica glass.
ルゴンを主成分とする請求項３または４に記載の方法。5. The method according to claim 3, wherein the gas used for high frequency sputtering has argon as a main component.
た磁性体微粒子分散含有する透明ガラスをさらに温度６
５０〜７００℃の範囲で熱処理することを特徴とする保
磁力を改善した透明ガラス材料。6. A transparent glass containing a dispersion of magnetic fine particles, which is obtained by the method according to claim 3, is further subjected to a temperature of 6
A transparent glass material with improved coercive force, characterized by being heat-treated in the range of 50 to 700 ° C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7240845A JP2799429B2 (en) | 1995-08-25 | 1995-08-25 | Glass material with coercive force |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7240845A JP2799429B2 (en) | 1995-08-25 | 1995-08-25 | Glass material with coercive force |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0967141A true JPH0967141A (en) | 1997-03-11 |
| JP2799429B2 JP2799429B2 (en) | 1998-09-17 |
Family
ID=17065568
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7240845A Expired - Lifetime JP2799429B2 (en) | 1995-08-25 | 1995-08-25 | Glass material with coercive force |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2799429B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6242085B1 (en) | 1997-09-17 | 2001-06-05 | Matsushita Electric Industrial Co., Ltd. | Magnetic recording medium and method for producing the same |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04325423A (en) * | 1991-04-25 | 1992-11-13 | Hoya Corp | Production of polarizing glass |
| JPH05119362A (en) * | 1991-10-28 | 1993-05-18 | Res Dev Corp Of Japan | Method for controlling fine crystal grain distribution of thin film of glass doped with fine crystal |
-
1995
- 1995-08-25 JP JP7240845A patent/JP2799429B2/en not_active Expired - Lifetime
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH04325423A (en) * | 1991-04-25 | 1992-11-13 | Hoya Corp | Production of polarizing glass |
| JPH05119362A (en) * | 1991-10-28 | 1993-05-18 | Res Dev Corp Of Japan | Method for controlling fine crystal grain distribution of thin film of glass doped with fine crystal |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6242085B1 (en) | 1997-09-17 | 2001-06-05 | Matsushita Electric Industrial Co., Ltd. | Magnetic recording medium and method for producing the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2799429B2 (en) | 1998-09-17 |
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