JPS6054247B2 - optical glass - Google Patents
optical glassInfo
- Publication number
- JPS6054247B2 JPS6054247B2 JP12204978A JP12204978A JPS6054247B2 JP S6054247 B2 JPS6054247 B2 JP S6054247B2 JP 12204978 A JP12204978 A JP 12204978A JP 12204978 A JP12204978 A JP 12204978A JP S6054247 B2 JPS6054247 B2 JP S6054247B2
- Authority
- JP
- Japan
- Prior art keywords
- glass
- devitrification
- tendency
- optical glass
- refractive index
- 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
- 239000005304 optical glass Substances 0.000 title claims description 9
- 239000000203 mixture Substances 0.000 claims description 3
- 238000004031 devitrification Methods 0.000 description 12
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 10
- ZKATWMILCYLAPD-UHFFFAOYSA-N niobium pentoxide Chemical compound O=[Nb](=O)O[Nb](=O)=O ZKATWMILCYLAPD-UHFFFAOYSA-N 0.000 description 10
- 239000011521 glass Substances 0.000 description 9
- 230000003287 optical effect Effects 0.000 description 8
- 239000006185 dispersion Substances 0.000 description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 6
- KKCBUQHMOMHUOY-UHFFFAOYSA-N Na2O Inorganic materials [O-2].[Na+].[Na+] KKCBUQHMOMHUOY-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- 229910000272 alkali metal oxide Inorganic materials 0.000 description 3
- 229910000149 boron phosphate Inorganic materials 0.000 description 3
- 229910052681 coesite Inorganic materials 0.000 description 3
- 229910052906 cristobalite Inorganic materials 0.000 description 3
- 239000000377 silicon dioxide Substances 0.000 description 3
- 235000012239 silicon dioxide Nutrition 0.000 description 3
- 229910052682 stishovite Inorganic materials 0.000 description 3
- PBCFLUZVCVVTBY-UHFFFAOYSA-N tantalum pentoxide Inorganic materials O=[Ta](=O)O[Ta](=O)=O PBCFLUZVCVVTBY-UHFFFAOYSA-N 0.000 description 3
- 229910052905 tridymite Inorganic materials 0.000 description 3
- MCMNRKCIXSYSNV-UHFFFAOYSA-N Zirconium dioxide Chemical compound O=[Zr]=O MCMNRKCIXSYSNV-UHFFFAOYSA-N 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- YBMRDBCBODYGJE-UHFFFAOYSA-N germanium dioxide Chemical compound O=[Ge]=O YBMRDBCBODYGJE-UHFFFAOYSA-N 0.000 description 2
- 239000000156 glass melt Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 229910019704 Nb2O Inorganic materials 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- DHAHRLDIUIPTCJ-UHFFFAOYSA-K aluminium metaphosphate Chemical compound [Al+3].[O-]P(=O)=O.[O-]P(=O)=O.[O-]P(=O)=O DHAHRLDIUIPTCJ-UHFFFAOYSA-K 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- KGBXLFKZBHKPEV-UHFFFAOYSA-N boric acid Chemical compound OB(O)O KGBXLFKZBHKPEV-UHFFFAOYSA-N 0.000 description 1
- 239000004327 boric acid Substances 0.000 description 1
- 239000005388 borosilicate glass Substances 0.000 description 1
- 150000004649 carbonic acid derivatives Chemical class 0.000 description 1
- 239000008395 clarifying agent Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 150000002823 nitrates Chemical class 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 239000005368 silicate glass Substances 0.000 description 1
- OGIDPMRJRNCKJF-UHFFFAOYSA-N titanium oxide Inorganic materials [Ti]=O OGIDPMRJRNCKJF-UHFFFAOYSA-N 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 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
- C03C3/062—Glass compositions containing silica with less than 40% silica by weight
- C03C3/064—Glass compositions containing silica with less than 40% silica by weight containing boron
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 Compositions (AREA)
Description
【発明の詳細な説明】
本発明は、屈折率ｎｄが１．６８乃至１．８４と大きく
、且つアツベ数νｄが２２乃至３２と小さい、高屈折率
高分散の光学性能範囲にある光学ガラスに関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an optical glass having a high refractive index, high dispersion, and a high refractive index nd of 1.68 to 1.84 and a small Abbe number νd of 22 to 32. .
従来上記した如き光学性能を具備する光学ガラスは、Ｔ
ｉＯ２を多量に含有する珪酸塩ガラスで作成されて来た
。Conventionally, optical glass having the above-mentioned optical performance is T.
They have been made of silicate glasses containing large amounts of iO2.
しかしながら、多量のＴＩＯ。を含有するガラスは、失
透傾向が極めて大きく、これを量産するには不適である
。上記の欠点を改善するために、ＴｉＯ２の増量に伴つ
て、アルカリ金属酸化物を増量せしめることが知られて
いるが、アルカリ金属酸化物を上記失透性が改善される
まで増量すると、本発明が得んとする高屈折率高分散の
光学的性能範囲は得られなくなり、その上ガラＪスの化
学的耐久性、機械的強度が劣化し、加えて熱膨張係数が
大きくなる。また同様の目的でＮｂ２Ｏ５とかＴａ。Ｏ
、等を導入せしめたガラスも公知である。即ち例えば、
特開昭４８−３４９１３号公報に示されるものは、Ｎｂ
。０５あるいはＴａ、ｑを導入し７て、屈折率の低下及
び失透を改善せんとしている。However, a large amount of TIO. Glasses containing these materials have an extremely large tendency to devitrify, making them unsuitable for mass production. In order to improve the above drawbacks, it is known that the amount of alkali metal oxide is increased as the amount of TiO2 is increased, but if the amount of alkali metal oxide is increased until the devitrification is improved, the present invention The optical performance range of high refractive index and high dispersion that is desired to be obtained cannot be obtained, and in addition, the chemical durability and mechanical strength of the glass deteriorate, and in addition, the coefficient of thermal expansion increases. Also, Nb2O5 or Ta is used for the same purpose. O
, etc. are also known. That is, for example,
What is shown in Japanese Patent Application Laid-open No. 48-34913 is Nb
. 05, Ta, and q are introduced to improve the decrease in refractive index and devitrification.
このようにＮｂ２Ｏ５あるいはＴａ２Ｏ５を導入すると
、失透傾向を大きくすることなく、高屈折率となすこと
はできるが、これを高分散とするためには多量のＴｉＯ
２あるいはＨｏを含有せしめねばなりらず、しかも失透
傾向は量産に適する程度迄には改善されず、加えてＰｂ
Ｏを含有せしめた場合には、失透析出温度が低温側へ拡
大し、プレス加工時における加熱程度でも失透を生じる
し、加えて熔融時には強い黄色の着色を呈することが判
つ５た。また、特公昭５１−２７４５０号公報に示され
るものは、Ｎｂ２Ｏ５を含有する硼珪酸塩ガラスとする
ことによつて失透傾向を改善せんとしているが、この内
本発明が得んとする光学性能範囲に属するガラスは、Ｎ
ｂ７Ｏ５と多量のＴｉＯ２とを含有するもので、ブレス
加工時に極めて失透し易い欠点を有するものであること
が判つた。本発明は、これら従来の欠点を除去し、前記
した光学的性能範囲の高屈折率高分散で、量産可能な光
学ガラスを得んとすることを目的とするものである。By introducing Nb2O5 or Ta2O5 in this way, a high refractive index can be achieved without increasing the tendency for devitrification, but in order to achieve high dispersion, a large amount of TiO is required.
However, the devitrification tendency has not been improved to the extent suitable for mass production, and in addition, Pb
It was found that when O is contained, the devitrification temperature increases to a lower temperature side, devitrification occurs even when heated at the time of press working, and in addition, a strong yellow coloration is exhibited when melted5. Furthermore, the glass disclosed in Japanese Patent Publication No. 51-27450 attempts to improve the devitrification tendency by using a borosilicate glass containing Nb2O5. Glass belonging to the range is N
It was found that it contained b7O5 and a large amount of TiO2, and had the drawback of being extremely susceptible to devitrification during pressing. The object of the present invention is to eliminate these conventional drawbacks and to obtain an optical glass that has a high refractive index and high dispersion within the above-mentioned optical performance range and can be mass-produced.
本発明に係る光学ガラスは、ＳｉＯ２−ＴｊＯ２一Ｎｂ
２Ｏ５−Ｎａ２Ｏ及びまたはＫ２Ｏ系のガラスを基礎と
して、これにＢＰＯ４及びまたはＡｌ（ＰＯ３）３をそ
の範囲を限定して導入することにより、高屈折率高分散
で、しかも失透傾向が極めて小さく、化学的耐久性及び
機械的強度に優れ、しかも好適な熱膨張係数を有し、更
に着色のない、量産可能なものである。The optical glass according to the present invention comprises SiO2-TjO2-Nb
Based on 2O5-Na2O and/or K2O glass, by introducing BPO4 and/or Al(PO3)3 in a limited range, it has a high refractive index and high dispersion, and has an extremely small tendency to devitrify. It has excellent chemical durability and mechanical strength, has a suitable coefficient of thermal expansion, is free from coloration, and can be mass-produced.
本発明に係る光学ガラスは、重量％において、下記の組
成より成る。The optical glass according to the present invention has the following composition in weight percent.
即ち、である。That is,.
次に、各成分並びにその重量％を上記範囲に限定した理
由を詳述する。Next, the reason why each component and its weight % are limited to the above ranges will be explained in detail.
ＳｉＯ２は、化学的耐久性を増し、機械的強度を増強し
、加えて熱膨張係数を良好にするためのものであるが、
その含有量を１０％より少なくすると、上記性質を示す
効果は著しく低下する上に、失透傾向が増大し、またこ
れを３５％より多くすると、本発明が目的とする光学的
性能に達し得なくなるので不適当である。SiO2 is used to increase chemical durability, enhance mechanical strength, and improve the coefficient of thermal expansion.
If the content is less than 10%, the effect of exhibiting the above properties will be significantly reduced, and the tendency to devitrify will increase, and if the content is more than 35%, the optical performance aimed at by the present invention cannot be achieved. It is inappropriate because it will disappear.
ＴｉＯ２は、その含有量を１５％より少なくすると、上
記本発明が目的とする光学的性能範囲に達することが不
能となり、不適当となり、また４５％より多くすると、
急激に失透傾向が増大すると共に、着色が著しくなるの
で、不適当である。When the content of TiO2 is less than 15%, it becomes impossible to reach the optical performance range aimed at by the present invention, making it unsuitable, and when it exceeds 45%,
This is unsuitable because the tendency to devitrify increases rapidly and the coloration becomes significant.
Ｎａ２Ｏ及びＫ２Ｏは、上記光学的性能範囲を得る上に
おいて、またガラス融液の粘度を調整する上において、
両者を同時に、あるいは単独で加えることを要するもの
であつて、Ｎａ２Ｏ＋Ｋ２Ｏの範囲をその調整上２０〜
３０％とすることを要するものである。ＢＰＯ４とＡｌ
（ＰＯ３），は、ＴｉＱ，及びＮｂ２Ｏ５の含有量が多
く、ＳｉＯ２及びアルカリ金属酸化物の含有７量が比較
的少ないガラスにおいて、失透防止剤として著しく有効
に作用するものであるが、これらの単独成分あるいは、
合量が１％より少ないと、その効果は殆ど得られず、こ
れが３０％より多くなると失透傾向が逆に増大するので
、不適当であ）る。Na2O and K2O are useful in obtaining the above optical performance range and in adjusting the viscosity of the glass melt.
It is necessary to add both at the same time or singly, and the range of Na2O + K2O is set at 20 to 20 for adjustment.
It is necessary to set it to 30%. BPO4 and Al
(PO3) acts extremely effectively as a devitrification preventive agent in glasses with a high content of TiQ and Nb2O5 and a relatively low content of SiO2 and alkali metal oxides. Single ingredient or
If the total amount is less than 1%, almost no effect can be obtained, and if it is more than 30%, the tendency to devitrify increases, which is inappropriate).
このとき、ＢＰＯ４及びＡｌ（ＰＯ３）３は、夫々最高
３０％及び１１％まで導入することができる。Ｎｂ２Ｏ
５は、ＴｉＯ２を多量に含有するガラスにおいて、その
失透傾向を抑制しつ）、上記ガラスを高屈折率高分散と
することができるものであるが、これを１１％より少な
くすると、その効果は極めて薄くなり、これを４０％よ
り多くすると、失透傾向が増大する上に、低分散となる
ため不適当である。またＴａ２Ｏ５、ＺｒＯ２及びＷＯ
３は、上記Ｎ■０５と置換して夫々１５％、５％及び５
％まで導入することができ、これによつて光学的性能を
調整することができる。ＡＳ２Ｏ３は、消色剤および清
澄剤として有効に作用するものであるため、ＴｉＯ２の
含有量が多く着色し易いガラスにおいては、必須の成分
であるが、これが０．１％より少なくなると、その作用
が急激に弱化し、またこれを１％より多くすると、失透
傾向が増大するので不適当である。At this time, BPO4 and Al(PO3)3 can be introduced up to a maximum of 30% and 11%, respectively. Nb2O
5 is a glass containing a large amount of TiO2, which can be made to have a high refractive index and high dispersion while suppressing its devitrification tendency, but when this is less than 11%, the effect is reduced. becomes extremely thin, and if it exceeds 40%, the tendency to devitrify increases and dispersion becomes low, which is inappropriate. Also Ta2O5, ZrO2 and WO
3 is 15%, 5% and 5% respectively by replacing the above N■05.
%, thereby adjusting the optical performance. AS2O3 acts effectively as a decolorizing agent and a clarifying agent, so it is an essential component in glass that has a high TiO2 content and is easily colored. However, when it is less than 0.1%, its effect is reduced. is unsuitable because it weakens rapidly, and increasing it more than 1% increases the tendency to devitrify.
Ｂ２Ｏ３，ＧｅＯ２及びＡｌ２ｑは、前記したＳｉＯ２
と置換して光学性能及びガラス融液の粘度調整のために
、これらを使用することができるが、これらが夫々１０
％、１０％及び５％より多くなると、失透析出温度が低
温側へ拡大され、ブレス加工時に失透するため不適当で
ある。B2O3, GeO2 and Al2q are the above-mentioned SiO2
These can be used to adjust the optical performance and the viscosity of the glass melt by replacing them with 10
%, 10%, and 5%, the devitrification temperature is expanded to a lower temperature side and devitrification occurs during pressing, which is inappropriate.
上記本発明に係る光学ガラスの成分となる原料は、Ｓｌ
Ｏ２，ＴｌＯ２，Ｎｂ２Ｏ５，Ｔａ２Ｏ５，ｚｒＯ２，
ＷＯ３，ＧｅＱ，，Ａｌ２Ｏ３及びＡＳ２Ｏ３にあつて
は、夫々の金属の酸化物を使用し、Ｎａ２Ｏ，Ｋ２Ｏは
、夫々の炭酸塩または硝酸塩を、Ｂ２Ｏ３は硼酸を、Ｂ
ＰＯ４，Ａｌ（ＰＯ３）３は硼リン酸、メタリン酸アル
ｂミを使用し、これらの混合物を通例のような白金容器
に入れ、１２００℃乃至１３００℃で熔解、清澄、攪拌
を行ない、適当な温度に予熱された鋳型に注入＊して徐
冷することによつて製造できる。The raw material that is a component of the optical glass according to the present invention is Sl
O2, TlO2, Nb2O5, Ta2O5, zrO2,
For WO3, GeQ, Al2O3 and AS2O3, oxides of the respective metals are used; for Na2O and K2O, their respective carbonates or nitrates; for B2O3, boric acid;
For PO4 and Al(PO3)3, borophosphoric acid and aluminum metaphosphate are used.The mixture is placed in a conventional platinum container, melted, clarified, and stirred at 1200°C to 1300°C. It can be manufactured by pouring into a mold that has been preheated to a certain temperature and slowly cooling it.
このようにして製造されたガラスは、殆ど無色で透明度
が高く、しかも化学的耐久性と機械的強度に優れ、膨張
係数が好適のものである。The glass thus produced is almost colorless, highly transparent, has excellent chemical durability and mechanical strength, and has a suitable coefficient of expansion.
上記本発明に係る光学ガラスの実施例を、その屈折率Ｎ
ｄ並びにアツベ数νｄと共に次表に示す。The above embodiment of the optical glass according to the present invention has a refractive index N
d and Atsube number νd are shown in the following table.
Claims (1)
ＳｉＯ＿２：１０〜３５％ＴｉＯ＿２：１５〜４５％ Ｎａ＿２Ｏ：０〜３０％，Ｋ＿２Ｏ：０〜３０％但し、
Ｎａ＿２Ｏ＋Ｋ＿２Ｏ：２０〜３０％ＢｐＯ＿４：０〜
３０％，Ａｌ（ｐＯ＿３）＿３：０〜１１％但し、Ｂｐ
Ｏ＿４＋Ａｌ（ｐＯ＿３）＿３：１〜３０％Ｎｂ＿２Ｏ
＿５：１１〜４０％，Ｔａ＿２Ｏ＿５：０〜１５％，Ｚ
ｒＯ＿２：０〜５％，ＷＯ＿３：０〜５％但し、Ｎｂ＿
２Ｏ＿５＋Ｔａ＿２Ｏ＿５＋ＺｒＯ＿２＋ＷＯ＿３：１
１〜４０％ＡＳ＿２Ｏ＿３：０．１〜１％Ｂ＿２Ｏ＿３
：０〜１０％ ＧｅＯ＿２：０〜１０％ Ａｌ＿２Ｏ＿３：０〜５％[Claims] Optical glass having the following composition in 1% by weight:
SiO_2: 10-35% TiO_2: 15-45% Na_2O: 0-30%, K_2O: 0-30% However,
Na_2O+K_2O: 20-30% BpO_4: 0-
30%, Al(pO_3)_3:0-11% However, Bp
O_4+Al(pO_3)_3:1~30%Nb_2O
_5: 11-40%, Ta_2O_5: 0-15%, Z
rO_2: 0-5%, WO_3: 0-5% However, Nb_
2O_5+Ta_2O_5+ZrO_2+WO_3:1
1-40% AS_2O_3: 0.1-1% B_2O_3
: 0~10% GeO_2: 0~10% Al_2O_3: 0~5%
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12204978A JPS6054247B2 (en) | 1978-10-05 | 1978-10-05 | optical glass |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12204978A JPS6054247B2 (en) | 1978-10-05 | 1978-10-05 | optical glass |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5551732A JPS5551732A (en) | 1980-04-15 |
| JPS6054247B2 true JPS6054247B2 (en) | 1985-11-29 |
Family
ID=14826334
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP12204978A Expired JPS6054247B2 (en) | 1978-10-05 | 1978-10-05 | optical glass |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6054247B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6234350A (en) * | 1985-08-02 | 1987-02-14 | ブラウプンクト−ヴエルケ・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング | Brake for tape recorder |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH01148726A (en) * | 1987-12-04 | 1989-06-12 | Sumita Kogaku Glass Seizosho:Kk | Optical glass |
| US6605834B1 (en) * | 1999-02-08 | 2003-08-12 | Lg Electronics Inc. | Dielectric for plasma display panel and composition thereof |
| EP1236693A1 (en) * | 2001-02-21 | 2002-09-04 | Gemmindustria Gaia Ferrando S.p.A. | A material, particularly for artificial stones of ornamental articles, a process for the preparation of this material and artificial stone made using this process |
| DE10133763C1 (en) * | 2001-07-11 | 2002-08-14 | Schott Glas | Lead-free optical heavy flint glasses |
| TWI250135B (en) | 2001-10-15 | 2006-03-01 | Hoya Corp | Optical glass, glass material for press molding, optical element, and method of manufacturing same |
| JP4990805B2 (en) * | 2001-10-15 | 2012-08-01 | Ｈｏｙａ株式会社 | Method for producing glass material for press molding, method for producing glass press-molded product, and method for producing optical element |
| JP4904590B2 (en) * | 2007-06-22 | 2012-03-28 | 清水建設株式会社 | Open caisson construction method |
| JP5545917B2 (en) | 2008-01-31 | 2014-07-09 | 株式会社オハラ | Optical glass |
-
1978
- 1978-10-05 JP JP12204978A patent/JPS6054247B2/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6234350A (en) * | 1985-08-02 | 1987-02-14 | ブラウプンクト−ヴエルケ・ゲゼルシヤフト・ミツト・ベシユレンクテル・ハフツング | Brake for tape recorder |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5551732A (en) | 1980-04-15 |
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