JPS6346015B2 - - Google Patents
Info
- Publication number
- JPS6346015B2 JPS6346015B2 JP12597681A JP12597681A JPS6346015B2 JP S6346015 B2 JPS6346015 B2 JP S6346015B2 JP 12597681 A JP12597681 A JP 12597681A JP 12597681 A JP12597681 A JP 12597681A JP S6346015 B2 JPS6346015 B2 JP S6346015B2
- Authority
- JP
- Japan
- Prior art keywords
- glass
- fine particles
- viscosity
- surface layer
- particles
- 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.)
- Expired
Links
- 239000010419 fine particle Substances 0.000 claims description 29
- 239000011521 glass Substances 0.000 claims description 25
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical group O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 16
- 239000002344 surface layer Substances 0.000 claims description 16
- 239000000654 additive Substances 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 11
- 238000004519 manufacturing process Methods 0.000 claims description 10
- 238000005245 sintering Methods 0.000 claims description 9
- 230000000996 additive effect Effects 0.000 claims description 6
- 229910052581 Si3N4 Inorganic materials 0.000 claims description 5
- HQVNEWCFYHHQES-UHFFFAOYSA-N silicon nitride Chemical compound N12[Si]34N5[Si]62N3[Si]51N64 HQVNEWCFYHHQES-UHFFFAOYSA-N 0.000 claims description 5
- 239000000377 silicon dioxide Substances 0.000 claims description 4
- 239000010410 layer Substances 0.000 claims description 3
- 235000012239 silicon dioxide Nutrition 0.000 claims description 3
- 239000011882 ultra-fine particle Substances 0.000 claims description 3
- 239000002245 particle Substances 0.000 description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 10
- 229910004298 SiO 2 Inorganic materials 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 6
- 239000007858 starting material Substances 0.000 description 6
- 229910052757 nitrogen Inorganic materials 0.000 description 5
- QJGQUHMNIGDVPM-UHFFFAOYSA-N nitrogen group Chemical group [N] QJGQUHMNIGDVPM-UHFFFAOYSA-N 0.000 description 5
- 239000007789 gas Substances 0.000 description 4
- 229910003902 SiCl 4 Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000010574 gas phase reaction Methods 0.000 description 3
- 150000004767 nitrides Chemical class 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- -1 He gas Chemical class 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 239000002019 doping agent Substances 0.000 description 2
- 230000000704 physical effect Effects 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 229910003910 SiCl4 Inorganic materials 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000011346 highly viscous material Substances 0.000 description 1
- 238000001513 hot isostatic pressing Methods 0.000 description 1
- 239000011859 microparticle Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000006060 molten glass Substances 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 239000005373 porous glass Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- FDNAPBUWERUEDA-UHFFFAOYSA-N silicon tetrachloride Chemical compound Cl[Si](Cl)(Cl)Cl FDNAPBUWERUEDA-UHFFFAOYSA-N 0.000 description 1
- 150000003384 small molecules Chemical class 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
Classifications
-
- 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
- C03C3/00—Glass compositions
- C03C3/04—Glass compositions containing silica
- C03C3/06—Glass compositions containing silica with more than 90% silica by weight, e.g. quartz
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Glass Melting And Manufacturing (AREA)
- Glass Compositions (AREA)
Description
【発明の詳細な説明】
本発明は高密度で透光性の秀れた添加物含有ガ
ラスの製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing additive-containing glass with high density and excellent light transmission.
一般にガラスの物性、例えば屈折率や透光性な
どの光学特性あるいは熱膨張係数などを変えるた
めガラス成分に添加物を配合することが行なわれ
る。ところが微粒子ガラスを焼結することにより
熔融ガラス体を造る場合添加物の種類によつては
該添加物をガラス成分中に含有させた為に軟化点
が上昇し、このためガラス微粒子の焼結が困難に
なり熔融した透明ガラス体を得られない場合があ
る。例えば窒素含有石英ガラスについては従前次
のようなUSP 4203744にみられるような製造方
法が知られている。この方法は、先づ第１図に示
すようにSiO2の微粒子状の石英ガラス１又は多
孔質ガラスを造り、次にこれをNH3含有雰囲気
中で処理した後これを焼結して窒素をドープした
石英ガラス３を得る方法である。ところがこの方
法では窒素含有量の多い透光性のあるガラス体を
得ることができなかつた。 Additives are generally added to glass components to change the physical properties of glass, such as optical properties such as refractive index and translucency, or coefficient of thermal expansion. However, when producing a molten glass body by sintering fine glass particles, depending on the type of additive, the softening point may rise due to the inclusion of the additive in the glass component, which may cause the sintering of the glass fine particles to increase. It may be difficult to obtain a molten transparent glass body. For example, for nitrogen-containing quartz glass, the following manufacturing method is known, as shown in USP 4203744. In this method, as shown in Figure 1, silica glass 1 or porous glass containing SiO 2 particles is first prepared, then treated in an atmosphere containing NH 3 and then sintered to remove nitrogen. This is a method for obtaining doped quartz glass 3. However, with this method, it was not possible to obtain a translucent glass body with a high nitrogen content.
本発明は上記欠点を解消し、比較的窒素含有量
の多い、かつ透光性のあるガラスを提供するもの
であつて、その構成は、内部よりも低粘度である
ガラス微粒子集合体を形成した後に、該微粒子集
合体を焼結することを特徴とする。 The present invention solves the above-mentioned drawbacks and provides a light-transmitting glass with a relatively high nitrogen content. Afterwards, the fine particle aggregate is sintered.
以下に本発明を実施例と共に詳細に説明する。 The present invention will be explained in detail below along with examples.
本発明はガラス微粒子の内部と外表面層との粘
性を変え、ガラス微粒子内部の粘度を高くし、外
表面層の粘度を低くすることを基本とする。 The present invention is based on changing the viscosity between the inside and the outer surface layer of the glass fine particles, increasing the viscosity inside the glass fine particles and lowering the viscosity of the outer surface layer.
添加物を含有させた時に、その粘性が高くな
り、このため、粘性流動により支配される焼結が
進まなくなる場合、本発明では、添加物を含有し
た超微粒子を合成し、この微粒子表面層の添加物
量を減少させることにより、又は添加物を含有し
た超微粒子の表面層上に、添加物の少ない層を合
成することにより微粒子表面を低粘性状態とし、
この物性により焼結を進める。出発材料のガラス
微粒子としては、透過させる光の波長よりも小さ
なガラス微粒子を用いる。例えば可視光が対象で
あれば、約0.5μｍ径以下が望ましい。 When additives are added, their viscosity becomes high, which prevents sintering controlled by viscous flow from progressing. In the present invention, ultrafine particles containing additives are synthesized and the surface layer of these particles is By reducing the amount of additives or by synthesizing a layer with less additives on the surface layer of ultrafine particles containing additives, the surface of the microparticles is brought into a low viscosity state,
This physical property facilitates sintering. As the starting material glass particles, glass particles smaller than the wavelength of the light to be transmitted are used. For example, if visible light is the target, the diameter is preferably about 0.5 μm or less.
本発明により窒素含有石英ガラスを製造する場
合、第２図に示すように先づ窒化硅素Si2N3の微
粒子１０を造り、該微粒子１０の外表面に二酸化
硅素SiO2の外表面層１１を形成し、これを焼結
して窒素含有石英ガラス１２を製造する。 When manufacturing nitrogen-containing quartz glass according to the present invention, first, as shown in FIG. 2, fine particles 10 of silicon nitride Si 2 N 3 are prepared, and an outer surface layer 11 of silicon dioxide SiO 2 is formed on the outer surface of the fine particles 10. The nitrogen-containing quartz glass 12 is manufactured by forming and sintering this.
焼結雰囲気としてはガラス成分に対し不活性で
ありかつ分子の小さなガス例えばHeガス等を用
いると、これらのガスはガラス中に容易に拡散
し、又、ガラス中に溶解し易いため気泡として残
らず、従つて残留気泡の一層少ないものが得られ
る。 If a gas that is inert to the glass components and has small molecules, such as He gas, is used as the sintering atmosphere, these gases will easily diffuse into the glass and dissolve in the glass, so they will not remain as bubbles. Therefore, fewer residual air bubbles are obtained.
次に内部が高粘性であり、外表面層が低粘性の
構成を有する微粒子を造るには次の２種類の方法
がある。第１の方法は高粘性を有する微粒子を出
発材料とし、この微粒子表面層の組成ないし成分
を反応処理して低粘性のものに変化させる方法で
ある。例えば出発材料として気相合成法などで得
られる窒化硅素微粒子Si3H4を用い、この粒子表
面を酸化処理して二酸化硅素SiO2の表面層を形
成する。この場合、急激な酸化処理は好ましくな
い。粒子が小さい場合窒化物の微粒子は酸化され
易く不安定なため急激に酸化すると局所的に粒子
全体が酸化物のシリカSiO2となり残留窒素が急
激に減少するからである。酸化処理の温度範囲と
しては700℃〜1200℃が好ましい。この範囲を超
えると酸化した微粒子が焼結し始め均一な酸化を
妨げる。上記微粒子を造る第２の方法は高粘性を
有する微粒子表面上に低粘性の膜をコーテイング
する方法である。 Next, there are two methods for producing fine particles having a high viscosity inside and a low viscosity outer surface layer. The first method is to use fine particles having high viscosity as a starting material, and to change the composition or components of the surface layer of the fine particles to a low-viscosity one by subjecting them to a reaction treatment. For example, silicon nitride fine particles Si 3 H 4 obtained by a vapor phase synthesis method are used as a starting material, and the particle surfaces are oxidized to form a surface layer of silicon dioxide SiO 2 . In this case, rapid oxidation treatment is not preferred. This is because when the particles are small, the nitride fine particles are easily oxidized and unstable, so if they are rapidly oxidized, the entire particle locally becomes an oxide, silica SiO 2 , and the residual nitrogen is rapidly reduced. The temperature range for the oxidation treatment is preferably 700°C to 1200°C. When this range is exceeded, oxidized fine particles begin to sinter and prevent uniform oxidation. The second method for producing the above-mentioned fine particles is to coat the surface of the high-viscosity fine particles with a low-viscosity film.
即ち、粘性の高い物質で核を形成し、この核の
表面に低粘性の物質を成長させるように気相反応
系の原料、反応条件を構成する。例えばSiO2−
B2O3系ガラスを得る場合、原料としてSiCl4、
BBr3、O2を用い、まず最初に約1200℃以上の反
応温度下でSiCl4、O2を供給しSiCl4→SiO2の均一
気相反応を進めてガラス微粒子の核を生成させ、
引き続きBBr3を供給し、BBr3→B2O3の反応を進
めて上記SiO2の表面にB2O3の膜を形成する。 That is, the raw materials and reaction conditions of the gas phase reaction system are configured so that a nucleus is formed from a highly viscous substance and a low viscosity substance is grown on the surface of this nucleus. For example, SiO 2 −
When obtaining B2O3 glass , SiCl4 ,
Using BBr 3 and O 2 , first supply SiCl 4 and O 2 at a reaction temperature of about 1200°C or higher to proceed with a homogeneous gas phase reaction of SiCl 4 → SiO 2 to generate nuclei of glass particles.
Subsequently, BBr 3 is supplied to advance the reaction of BBr 3 →B 2 O 3 to form a B 2 O 3 film on the surface of the SiO 2 .
次に微粒子を集合して焼結するには次のような
方法によればよい。第１の方法は、高粘性の微粒
子１０を出発材料とし、この微粒子の表面に前述
したような表面処理反応又は低粘性膜のコーテイ
ングにより低粘性の表面層１１を形成し、その後
この表面層を有する微粒子を集合させた後に焼結
する（第３図ａ参照）。第２の方法は、第１の方
法と同様に表面層を有する微粒子を形成した後、
熱間静圧成形などにより微粒子集合体を成形する
と同時に焼結する（第３図ｂ参照）。第３の方法
は予め静圧成形などにより微粒子集合体を形成し
た後、前述したような表面処理反応又は低粘性膜
のコーテイングにより個々の粒子表面に低粘性の
表面層を形成し、これを焼結する（第３図ｃ参
照）。 Next, the following method may be used to collect and sinter the fine particles. In the first method, high-viscosity fine particles 10 are used as a starting material, a low-viscosity surface layer 11 is formed on the surface of the fine particles by a surface treatment reaction as described above or coating with a low-viscosity film, and then this surface layer is coated with a low-viscosity film. After the fine particles are aggregated, they are sintered (see Figure 3a). In the second method, after forming fine particles having a surface layer in the same way as the first method,
The fine particle aggregate is formed by hot isostatic pressing or the like and sintered at the same time (see FIG. 3b). The third method is to form a fine particle aggregate in advance by static pressure molding, etc., then form a low-viscosity surface layer on the surface of each particle by surface treatment reaction or coating with a low-viscosity film as described above, and then bake this. (See Figure 3c).
次に本発明の実施例を示す。 Next, examples of the present invention will be shown.
実施例 １
出発材料として、SiCl4とNH3とを高周波プラ
ズマ火炎中の高温帯にて反応させた後急冷し、補
集して得た微粒子状窒化硅素を用意した。この粒
子はほぼ球状で約0.5μｍ程度の粒径を有する。こ
の粒子の粉末をペレツト状（15mm〓×15mm）に加
圧成形し、この成形体を焼結炉内にセツトした。Example 1 As a starting material, fine particulate silicon nitride was prepared by reacting SiCl 4 and NH 3 in a high-temperature zone in a high-frequency plasma flame, followed by rapid cooling and collection. The particles are approximately spherical and have a particle size of about 0.5 μm. This powder of particles was press-molded into a pellet shape (15 mm x 15 mm), and this compact was set in a sintering furnace.
炉内温度を500℃に保ち、Heガス100c.c.／分流
した状態で、約10時間保持した。この後、炉内温
度を900℃に上昇させ、O2を50c.c.／分加え、２時
間保持した。引き続きO2を停止し、Heを流した
まま炉温を1600℃に上昇させ、この状態で30分保
持した後、約２時間かけて、試料を室温程度に下
げた。得られた試料は殆んど透明であり、窒素の
含有量が約５重量パーセントの窒素含有シリカガ
ラスが得られた。 The temperature inside the furnace was maintained at 500°C, and He gas was kept flowing at 100c.c./minute for about 10 hours. Thereafter, the temperature inside the furnace was raised to 900° C., O 2 was added at 50 c.c./min, and the temperature was maintained for 2 hours. Subsequently, the O 2 supply was stopped, and the furnace temperature was raised to 1600° C. while He was flowing. After maintaining this state for 30 minutes, the sample was cooled to about room temperature over about 2 hours. The resulting sample was almost transparent, yielding a nitrogen-containing silica glass with a nitrogen content of approximately 5 weight percent.
以上、主に窒素含有石英ガラスを例にして本発
明を説明したが、本発明は上記のものに限らず、
硅素以外の窒化物例えばBN、Ti3N4、AlNなど
についても適用でき、また更に窒化物以外の化合
物についても適用できる。例えば出発材料として
酸化物の微粒子を用い該酸化物微粒子の表面にド
ーパントを含む低粘性の表面層を気相反応にて形
成し、これを焼結することによりドーパント含有
量の大きな透光性の秀れたガラスを容易に製造す
ることができる。また本発明はその他の複合材料
にも適用することができる。 The present invention has been explained above mainly using nitrogen-containing quartz glass as an example, but the present invention is not limited to the above.
It can also be applied to nitrides other than silicon, such as BN, Ti 3 N 4 , AlN, etc., and it can also be applied to compounds other than nitrides. For example, by using oxide fine particles as a starting material, forming a low-viscosity surface layer containing a dopant on the surface of the oxide fine particles through a gas phase reaction, and sintering this, a light-transmitting layer with a large dopant content is formed. Excellent glass can be manufactured easily. The present invention can also be applied to other composite materials.
第１図は従来の製造方法の説明図、第２図は本
発明の製造原理を示す説明図、第３図ａ，ｂ，ｃ
は本発明の製造手順の概略を示す説明図である。
図面中、１……SiO2微粒子、２……窒化硅素の
表面層、３……窒素ドープした石英ガラス、１０
……微粒子、１２……焼結体である。
Fig. 1 is an explanatory diagram of the conventional manufacturing method, Fig. 2 is an explanatory diagram showing the manufacturing principle of the present invention, and Fig. 3 a, b, c.
FIG. 1 is an explanatory diagram showing an outline of the manufacturing procedure of the present invention.
In the drawing, 1...SiO 2 fine particles, 2...Silicon nitride surface layer, 3...Nitrogen-doped silica glass, 10
...Fine particles, 12... Sintered body.
Claims (1)
粒子集合体を形成した後に該微粒子の集合体を焼
結することを特徴とする添加物含有ガラスの製造
方法。 ２ 前記ガラス微粒子の内部が窒化硅素であり、
外表面層が二酸化硅素であることを特徴とする特
許請求の範囲第１項記載の添加物含有ガラスの製
造方法。 ３ 前記ガラス微粒子の直径が0.5μｍ以下の超微
粒子であることを特徴とする第１項又は第２項記
載の添加物含有ガラスの製造方法。[Scope of Claims] 1. A method for manufacturing additive-containing glass, which comprises forming an aggregate of glass fine particles in which the outer surface layer has a lower viscosity than the inner layer, and then sintering the aggregate of the fine particles. 2 The interior of the glass fine particles is silicon nitride,
2. The method for producing additive-containing glass according to claim 1, wherein the outer surface layer is silicon dioxide. 3. The method for producing additive-containing glass according to item 1 or 2, wherein the glass fine particles are ultrafine particles having a diameter of 0.5 μm or less.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12597681A JPS5832037A (en) | 1981-08-13 | 1981-08-13 | Preparation of glass containing additive |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12597681A JPS5832037A (en) | 1981-08-13 | 1981-08-13 | Preparation of glass containing additive |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5832037A JPS5832037A (en) | 1983-02-24 |
| JPS6346015B2 true JPS6346015B2 (en) | 1988-09-13 |
Family
ID=14923642
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12597681A Granted JPS5832037A (en) | 1981-08-13 | 1981-08-13 | Preparation of glass containing additive |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5832037A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2525538Y2 (en) * | 1990-03-02 | 1997-02-12 | 三菱鉛筆株式会社 | Liquid applicator |
| JP2525539Y2 (en) * | 1990-03-02 | 1997-02-12 | 三菱鉛筆株式会社 | Liquid applicator |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6042244A (en) * | 1983-08-12 | 1985-03-06 | Toshiba Ceramics Co Ltd | Quartz glass having resistance to melting loss |
| JPH0657614B2 (en) * | 1985-09-13 | 1994-08-03 | 株式会社フジクラ | Method for manufacturing optical fiber preform |
-
1981
- 1981-08-13 JP JP12597681A patent/JPS5832037A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2525538Y2 (en) * | 1990-03-02 | 1997-02-12 | 三菱鉛筆株式会社 | Liquid applicator |
| JP2525539Y2 (en) * | 1990-03-02 | 1997-02-12 | 三菱鉛筆株式会社 | Liquid applicator |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5832037A (en) | 1983-02-24 |
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