JPS60161352A - Glass for annular fluorescent lamp - Google Patents
Glass for annular fluorescent lampInfo
- Publication number
- JPS60161352A JPS60161352A JP1790784A JP1790784A JPS60161352A JP S60161352 A JPS60161352 A JP S60161352A JP 1790784 A JP1790784 A JP 1790784A JP 1790784 A JP1790784 A JP 1790784A JP S60161352 A JPS60161352 A JP S60161352A
- Authority
- JP
- Japan
- Prior art keywords
- glass
- pbo
- bao
- sro
- annular fluorescent
- 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
-
- 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
- C03C3/076—Glass compositions containing silica with 40% to 90% silica, by weight
- C03C3/102—Glass compositions containing silica with 40% to 90% silica, by weight containing lead
- C03C3/105—Glass compositions containing silica with 40% to 90% silica, by weight containing lead containing aluminium
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- 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)
Abstract
Description
【発明の詳細な説明】
〔発明の技術分野〕
本発明は環形螢光ランプ用ガラスに係り、特暑こ熱加工
性の優れたガラス組成物に関する。DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a glass for annular fluorescent lamps, and more particularly to a glass composition having excellent heat processability.
一般に環形螢光ランプの製造は直管ガラスからなる気密
容器の内壁に螢光体を被着させ、その両端部をこ電極を
保持するステムを封止し、これを電気炉等で700〜8
00℃に加熱軟化させて成形ドラムに捲回して環形に成
形するものであるが、このガラス製気密容器を形成する
ガラスは従来上記環形成形時の熱加工の容易さから鉛酸
化物pbOを4〜28重量%含有する鉛ガラスが使われ
ていた。In general, annular fluorescent lamps are manufactured by coating the inner wall of an airtight container made of straight glass with a phosphor, sealing both ends of the stem that holds the electrodes, and heating this in an electric furnace or the like to
The glass used to form this airtight glass container is softened by heating to 00°C and wound around a forming drum to form a ring shape. Conventionally, the glass used to form this glass airtight container is made of lead oxide pbO 4. A lead glass containing ~28% by weight was used.
また最近は軽量化とコストダウンの目的から直管形螢光
ランプのガラスバルブや一般照明亀球バルグに用いられ
るソーダ石灰ガラスの使用も試みられ、既に一部は市販
されているが未だ問題点が残されていた。Recently, attempts have been made to use soda lime glass, which is used in glass bulbs for straight tube fluorescent lamps and general lighting bulbs, for the purpose of weight reduction and cost reduction, and although some are already on the market, there are still problems. was left behind.
一般にPbOを多量に含有するガラス(以下鉛ガラスと
いう)は鉛原料の飛散およびガラス溶解時ないし成形・
加工時の鉛成分の揮散による環境汚染等を防止するため
、多大の作業環境整備費用を要するうえに原料費も嵩み
、また製品自体の重量が重くなるなどの欠点があった。In general, glass containing a large amount of PbO (hereinafter referred to as lead glass) suffers from the scattering of lead raw materials during glass melting or molding.
In order to prevent environmental pollution due to the volatilization of lead components during processing, a large amount of work environment maintenance costs are required, and raw material costs also increase, and the product itself becomes heavier.
そのため安価で比重の小さいソーダ石灰ガラスへの転換
が行なわれているが、ソーダ石灰ガラスは上記鉛ガラス
に比べて熱加工温度が約100℃高くなるため、加工時
の歩留は勿論、螢光体や結着剤とガラス管との間に物理
的および化学的反応を生じ、螢光体が変質し、環形螢光
ランプの初期光束および光束維持率を劣化させる問題が
生じた。For this reason, a switch has been made to soda-lime glass, which is cheaper and has a lower specific gravity. However, since soda-lime glass has a thermal processing temperature approximately 100°C higher than the above-mentioned lead glass, the yield rate during processing is affected, as well as the fluorescence. Physical and chemical reactions occur between the body or binder and the glass tube, resulting in deterioration of the phosphor and deterioration of the initial luminous flux and luminous flux maintenance rate of the annular fluorescent lamp.
従って環形螢光ランプ用ガラスとしては曲げ加工が容易
をこできるような粘性特性を有することが必須条件であ
り、それをこは軟化温度は出来るだけ低く、かつ作業温
度付近の粘性曲線は緩やかで作業温度域の広いものが望
まれている。Therefore, it is essential for glass for annular fluorescent lamps to have viscosity properties that can be easily bent, and this requires that the softening temperature be as low as possible and the viscosity curve near the working temperature be gentle. A wide working temperature range is desired.
また膨張係数は鉛ガラスを用いるステムガラスとの封着
性の関係から0〜300℃の温度範囲で91〜103
X 10−’/の範囲に規制される。化学的耐久性は貯
蔵時のウェザリングによるアルカリ分、析出等の問題が
発生するおそれがあり、大阪工業試験新法による試験で
8 m −Q /N/ 100HCfi以下を必要とす
る。In addition, the expansion coefficient is 91 to 103 in the temperature range of 0 to 300°C due to the sealing property with stem glass using lead glass.
It is limited to a range of X 10-'/. Regarding chemical durability, problems such as alkali content and precipitation may occur due to weathering during storage, and a test based on the new Osaka Industrial Testing Method requires 8 m-Q/N/100HCfi or less.
以上の特性をすべて満足するガラス組成物は未だ開発さ
れていない。A glass composition that satisfies all of the above characteristics has not yet been developed.
本発明は上記事情に鑑みてなされたものであり、その目
的とするところは、環形螢光ランプ用ガラスとしてラン
グ特性を向上させるため、熱加工性のよいソーダ石灰系
ガラスを提供することである。The present invention has been made in view of the above circumstances, and its object is to provide a soda-lime-based glass with good heat processability in order to improve Lang properties as a glass for annular fluorescent lamps. .
本発明は上記目的を達成するために、従来のソーダ石灰
系ガラスに0.1〜2%のPbOを導入し、BaOおよ
びSrOと共存させることによって従来の鉛ガラス系、
またはB2O3、BaOおよびSrOを主体に導入した
ソーダ石灰系ガラスに比べて奢るしく熱加工性の優れた
ガラス組成を開発したものである。In order to achieve the above object, the present invention introduces 0.1 to 2% of PbO into the conventional soda-lime glass and makes it coexist with BaO and SrO.
Alternatively, a glass composition has been developed that is more luxurious and has superior heat processability compared to soda-lime-based glasses that mainly incorporate B2O3, BaO, and SrO.
即ちランプ特性としての初期光束および光束維持率は、
ランプの働程特性として最も重要な特性であるが、本発
明者らはその中でも特にガラス材質と結着剤および螢光
体との高温時における物理的および化学的反応が、最も
大きな影響を及ぼしていることを見い出した。In other words, the initial luminous flux and luminous flux maintenance rate as lamp characteristics are:
This is the most important characteristic of a lamp's operating cycle, and the inventors have found that the physical and chemical reactions between the glass material, binder, and phosphor at high temperatures have the greatest influence. I found out that
そのためには環形成形時の曲げ加工温度を出来るだけ低
くシ、螢光体および結着剤の変質を防止すると共をこ、
ガラスバルブの管壁への喰い込みを防止する必要がある
。一般的にはソーダ石灰ガラスのアルカリ酸化物含量を
増加すれば、軟化温度は低下して熱加工性はよくなるが
、その反面化学的耐久性が劣化してウェザリングが発生
し、また膨張係数も大きくしてステムガ)スとの封着性
の問題があって無闇に増加することはできない。本発明
者らは種々実験の結果、ソーダ石灰ガラス中にPbOを
少量添加することで著るしく熱加工性が改良されること
、およびBaOとSrOとPbOとを共存させることで
より一層その効果が顕著となることを見い出した。To achieve this, the bending temperature during ring forming should be kept as low as possible to prevent deterioration of the phosphor and binder.
It is necessary to prevent the glass bulb from digging into the pipe wall. In general, increasing the alkali oxide content of soda-lime glass lowers the softening temperature and improves thermal processability, but on the other hand, it deteriorates chemical durability, causes weathering, and increases the coefficient of expansion. Due to the problem of sealing properties with stem gas, it is not possible to increase the number of stem gases. As a result of various experiments, the present inventors have found that adding a small amount of PbO to soda-lime glass significantly improves thermal processability, and that the effect is further improved by coexisting BaO, SrO, and PbO. was found to be significant.
即ち本発明の要旨は重量百分率で5iO260〜75%
、kL20s O,5〜4%、Na、012〜17%、
K2O0〜3%(但し0は含まず)Liz00〜1%(
但し0は含まず、カッNa2Oとに20とLi2Oとの
和が13〜18.5%)0601〜8%、M5i00.
5〜3%、BaO0〜2% (但し0を含ます゛)、8
r00.〜2%(但し0を含ます入Pb00.1〜2%
、(但しBaOとSrOとPbOとの和が0.2〜2.
5%)、B20sO〜3%(但しOを含まず)bAsz
ch O〜0.6%(但しOを含まず)、5bzOs
O〜0.5%(但し0を含まず、かつAg2O3と5b
zOxとの和が0.02〜0.8%)の組成を有する環
形螢光ラング用ガラスである。That is, the gist of the present invention is 5iO260-75% by weight percentage.
, kL20s O, 5-4%, Na, 012-17%,
K2O0~3% (however, 0 is not included) Liz00~1% (
However, 0 is not included, and the sum of Na2O, 20 and Li2O is 13-18.5%)0601-8%, M5i00.
5-3%, BaO 0-2% (including 0゛), 8
r00. ~2% (including 0) Input Pb00.1~2%
, (However, the sum of BaO, SrO and PbO is 0.2 to 2.
5%), B20sO ~ 3% (excluding O) bAsz
ch O ~ 0.6% (not including O), 5bzOs
O ~ 0.5% (however, does not include 0, and contains Ag2O3 and 5b
This is a glass for annular fluorescent rung having a composition of 0.02 to 0.8%).
次に上記組成範囲の数値限定理由について詳述する。Next, the reason for limiting the numerical value of the above composition range will be explained in detail.
s io、はガラス形成の必須成分の一つであるが、6
0%未満では膨張係数が高(なり化学的耐久性が劣化す
るので好ましくない。また75゛%を越えると膨張係数
が低くなり過ぎ、軟化温度も高くなり環形成形が困難と
なる。望ましくは65〜73%である。Afi203は
0.5%未満では化学的耐久性が劣化し、4%を越える
とガラスが不均質となり、脈理不良が増加する。望まし
くは1〜3%である。s io, is one of the essential components for glass formation, but 6
If it is less than 0%, the expansion coefficient is high (and the chemical durability deteriorates, which is undesirable. If it exceeds 75%, the expansion coefficient becomes too low, the softening temperature becomes high, and ring formation becomes difficult. Desirably 65%). If Afi203 is less than 0.5%, the chemical durability will deteriorate, and if it exceeds 4%, the glass will become non-uniform and the number of striae defects will increase.It is preferably 1 to 3%.
Na*012%未満かツNazoとに20とLi1Oと
の和が13%未満であると軟化温度が高くなり環形成形
が難かしくなるうえ、膨張係数も低くなり過ぎる。If the sum of Na*020 and Li1O is less than 12% or less than 13%, the softening temperature will be high, making it difficult to form a ring, and the expansion coefficient will also be too low.
またNanoが17%%およびKxOが3%、かツNa
、oとに、OとLi2Oとの和が18,5%を越えると
膨張係数が大きくなり過ぎ、化学的耐久性と電気絶縁性
が低下する。Li 20は少量の添加でも溶融促進に大
きな効果を有するが、高価であるため1%以内とした。Also, Nano was 17%%, KxO was 3%, and Na
, o, and if the sum of O and Li2O exceeds 18.5%, the expansion coefficient becomes too large and the chemical durability and electrical insulation properties decrease. Although Li 20 has a great effect on promoting melting even when added in a small amount, it is expensive, so it was limited to 1% or less.
CaOおよびMjIOのアルカリ土類金属酸化物は電気
絶縁性および化学的耐久性を向上させるが、Ca01%
沫満およびMり0α5%未満ではその効果が期待できず
、CaO3%およびMjlo 3%を越えるとガラスを
失透させる傾向が強くなり好ましくない。またCaOお
よびMjIOは高温粘性は低下させる効果があるが、作
業温度域以下では粘性を上げる1効果があるため軟化温
度を低下させる目的・こは好ましくない。Alkaline earth metal oxides of CaO and MjIO improve electrical insulation and chemical durability, but CaO1%
If the content and M content are less than 5%, no effect can be expected, and if the content exceeds 3% CaO and 3%, the glass tends to devitrify, which is not preferable. Further, although CaO and MjIO have the effect of lowering high temperature viscosity, they have the effect of increasing viscosity below the working temperature range, so they are not preferred for the purpose of lowering the softening temperature.
本発明は環形成形時の作業性を改良するため番二ソーダ
石灰ガラスへ必須成分の一つとしてPbOを0.1〜2
%添加し、併せてBaO9〜2%および5r00〜2%
を添加し、かつPbOとBaOとSrOとの合量が0.
2〜2.5%となるようにした点に特徴がある。即ちp
boo、i%未満、かツPbOとBaOとSrOとの合
量が0.2%以下では作業温度付近の粘性を低下させる
ことができず、またPbOが2%を越え、かつPbOと
BaOとSrOとの合量が2..5%を越えると失透性
傾向が増加し好ましくない。The present invention adds 0.1 to 2 PbO as one of the essential components to Banji soda lime glass in order to improve workability during ring forming.
% added, combined with BaO9~2% and 5r00~2%
is added, and the total amount of PbO, BaO, and SrO is 0.
It is distinctive in that it is set to 2 to 2.5%. That is, p
If the total amount of PbO, BaO and SrO is less than 0.2%, the viscosity near the working temperature cannot be lowered, and if PbO exceeds 2% and PbO and BaO The total amount with SrO is 2. .. If it exceeds 5%, the tendency towards devitrification increases, which is not preferable.
B2O3は溶融性を向上させ、かつ化学的耐久性も向上
させるが3%を越えると軟化温度を上昇させるうえ、溶
融にスカムを発生し易くするので好ましくない。Asz
osおよび5bzOsは共に清澄剤として使用され、ま
た溶融ガラスを酸化雰囲気状態に維持しFe”+による
ガラスの着色を防止する効果も有するが、その合量が0
.02%未満では効果が期待できず、またASzOa
0.6%、および8bzOs 0.5%かつAs、0.
とSb 20mとの合量が0.8%を越えると熱加工時
に再発泡して泡不良を作るので好ましくない。B2O3 improves melting properties and chemical durability, but if it exceeds 3%, it increases the softening temperature and tends to cause scum during melting, which is not preferred. Asz
Both os and 5bzOs are used as refining agents, and also have the effect of maintaining molten glass in an oxidizing atmosphere and preventing glass coloring due to Fe"+, but when the total amount is 0.
.. If it is less than 0.02%, no effect can be expected, and ASzOa
0.6%, and 8bzOs 0.5% and As, 0.
If the total amount of Sb 20m and Sb 20m exceeds 0.8%, it is not preferable because foaming may occur again during heat processing, resulting in defective foaming.
以下に本発明の詳細な説明する。第1表は本発明に係る
環形螢光ランプ用ガラスの実施例と従来品の比較例を示
す。The present invention will be explained in detail below. Table 1 shows examples of the glass for annular fluorescent lamps according to the present invention and comparative examples of conventional products.
第 1 表
比較例1は鉛ガラスの従来例であり、比較例2は改良前
のソーダ石灰ガラスの従来例である。実施例1〜6は本
発明による実施例である。Table 1 Comparative Example 1 is a conventional example of lead glass, and Comparative Example 2 is a conventional example of soda lime glass before improvement. Examples 1 to 6 are examples according to the present invention.
膨張係数は0〜300℃間の平均熱膨張係数であり、軟
化温度は粘性xo7Js ボイズに相当する温度であり
、それぞれJI8R3102rガラスの線膨張係数の測
定方法」およびJIS几3104 rガラスの軟化温度
測定方法」に準拠して測定した値を示した。The expansion coefficient is the average thermal expansion coefficient between 0 and 300°C, and the softening temperature is the temperature corresponding to the viscosity xo7Js voids, respectively. The values measured in accordance with ``Method'' are shown.
作業温度は粘性10’ボイズに相当する温度を高温粘性
測定曲線より読み取り、その値を表示した。As for the working temperature, the temperature corresponding to viscosity of 10' voids was read from the high temperature viscosity measurement curve, and the value was displayed.
本発明の実施例によれば環形成形時の加工温度は比較例
2に示した従来のソーダ石灰ガラスより低く、比較例1
にほぼ近い作業温度を示し、熱加工が容易をこなったこ
とが理解される。According to the embodiment of the present invention, the processing temperature during ring forming is lower than that of the conventional soda lime glass shown in Comparative Example 2;
It is understood that the working temperature was almost close to that of , and that the thermal processing was easy.
更に上記実施例のうち代表例として実施例No、INo
、 3およびN095のガラスバルブを使用して30W
環形螢光ランプを試作しランプ特性を評価した。実施例
No、 I No、 2 kよびN005で製作したラ
ンプと従来品の比較例No、 1およびNα2とのラン
プ特性の比較を第2表に示す。Furthermore, as representative examples among the above-mentioned examples, Example No. and INo.
, 30W using 3 and N095 glass bulbs
A prototype ring-shaped fluorescent lamp was manufactured and the lamp characteristics were evaluated. Table 2 shows a comparison of the lamp characteristics between the lamps manufactured in Examples No., I No. 2k, and No. 005 and the conventional comparative examples No. 1 and Nα2.
本発明をこよる実施例ガラスを使用した環形螢光ランプ
は上表の如くランプ特性が従来のソーダ石灰ガラス・こ
比べて著るしく向上し、製造工程における歩留も良好で
あった。またステムガラスとの封着性も良く、工程間で
発生するクラックおよびリーク不良等は現行ガラスと同
等であった。As shown in the table above, the annular fluorescent lamp using the example glass according to the present invention had significantly improved lamp characteristics as compared to the conventional soda-lime glass, and the yield in the manufacturing process was also good. It also had good sealing properties with stem glass, and cracks and leak defects that occurred during the process were comparable to those of current glass.
以上説明したように本発明による環形螢光ランプ用ガラ
スは熱加工性がよく、ランプ特性もよくかつ化学的耐久
性および耐失透性に優れ、直管形および環形のいずれの
管球ガラスとしても使用できる。As explained above, the glass for annular fluorescent lamps according to the present invention has good heat processability, good lamp properties, and excellent chemical durability and devitrification resistance, and can be used as a tube glass for both straight tube and ring shapes. can also be used.
特許出願人 東芝硝子株式会社Patent applicant: Toshiba Glass Corporation
Claims (1)
,5〜4%、N172012〜17%、N200〜3%
(但し0を含まず)、Liz00〜1%(但し0を含ま
ず、かツNa2Oとに、0とLi2Oとの和が13〜1
8.5%)、Ca01〜8%、Mfoo、 5〜3.%
、Ba0O〜2%(但し0を含まず)、5r00〜2%
(但し0を含まず)、Pb00.1〜2% (但しBa
Oと8rOとPbOとの和が0.1〜2.5%)、B2
O30〜3%(但し0を含まず)、Ag2O30〜0.
6%(但し0を含まず)、5bzOs O〜0.5%(
但しOを含まず、かつAs2O3と5bzOaとの和が
0,02〜0.8%)の組成を有することを特徴とする
環形螢光ランプ用ガラス。8i0z 60-75% by weight percentage, Al-2030
,5~4%, N172012~17%, N200~3%
(However, 0 is not included), Liz00~1% (However, 0 is not included, and the sum of 0 and Li2O is 13~1.
8.5%), Ca01-8%, Mfoo, 5-3. %
, Ba0O~2% (excluding 0), 5r00~2%
(however, 0 is not included), Pb00.1~2% (however, Ba
The sum of O, 8rO and PbO is 0.1 to 2.5%), B2
O30~3% (excluding 0), Ag2O30~0.
6% (excluding 0), 5bzOs O~0.5% (
A glass for an annular fluorescent lamp characterized in that it does not contain O and has a composition in which the sum of As2O3 and 5bzOa is 0.02 to 0.8%.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1790784A JPS60161352A (en) | 1984-02-01 | 1984-02-01 | Glass for annular fluorescent lamp |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP1790784A JPS60161352A (en) | 1984-02-01 | 1984-02-01 | Glass for annular fluorescent lamp |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS60161352A true JPS60161352A (en) | 1985-08-23 |
JPS6357374B2 JPS6357374B2 (en) | 1988-11-11 |
Family
ID=11956813
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP1790784A Granted JPS60161352A (en) | 1984-02-01 | 1984-02-01 | Glass for annular fluorescent lamp |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS60161352A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007018981A1 (en) * | 2005-08-04 | 2007-02-15 | Guardian Industries Corp. | Glass composition for improved refining and method |
-
1984
- 1984-02-01 JP JP1790784A patent/JPS60161352A/en active Granted
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2007018981A1 (en) * | 2005-08-04 | 2007-02-15 | Guardian Industries Corp. | Glass composition for improved refining and method |
US7772144B2 (en) | 2005-08-04 | 2010-08-10 | Guardian Industries Corp. | Glass composition for improved refining and method |
Also Published As
Publication number | Publication date |
---|---|
JPS6357374B2 (en) | 1988-11-11 |
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