CN101146748A - Ultraviolet absorbing glass, glass tube for fluorescent lamp using same, and method for producing ultraviolet absorbing glass for fluorescent lamp - Google Patents

Abstract

Disclosed is an ultraviolet absorbing glass for fluorescent lamps which is composed of a borosilicate glass containing, in mass%, 60-80% of SiO<SUB>2</SUB>, 1-7% of Al<SUB>2</SUB>O<SUB>3</SUB>, 10-25% of B<SUB>2</SUB>O<SUB>3</SUB>, 3-15% of Li<SUB>2</SUB>O + Na<SUB>2</SUB>O + K<SUB>2</SUB>O, 0-5% of CaO + MgO + BaO + SrO + ZnO, 0.001-0.05% of Fe<SUB>2</SUB>O<SUB>3</SUB>, 0.1-5% of CeO<SUB>2</SUB>, 0.01-5% of SnO + SnO<SUB>2</SUB> and 0.01-5% of ZrO<SUB>2</SUB> + ZnO + Nb<SUB>2</SUB>O<SUB>5</SUB>, and having an average linear expansion coefficient in the range of 0-300 DEG C of 36-57 10<SUP>-7</SUP>/ DEG C which is determined in accordance with JISR 3102.

Description

Ultraviolet absorbing glass and adopt the manufacture method of the fluorescent-lamp-use Glass tubing and the fluorescent-lamp-use ultraviolet absorbing glass of this glass

Technical field

The present invention relates to ultraviolet absorbing glass, relate to the glass of the backlight used luminescent lamp of display unit such as the peripherals, the especially liquid-crystal display that are applicable to the light source of following ultra violet radiation (below be sometimes referred to as LCD), and adopt the fluorescent-lamp-use Glass tubing of this glass and the manufacture method of fluorescent-lamp-use ultraviolet absorbing glass.

Background technology

In recent years, as the key device of multi-media relevant device, extensively adopt liquid-crystal display (below be sometimes referred to as LCD), but when its purposes enlarges, also require lightweight, slimming, low consumption electrification, high brightnessization, cost degradation etc.Especially, even in LCD, also require high-quality display unit with aspects such as indicating meter, on-vehicle display, TV Monitors in PC.On the other hand, because the right and wrong of liquid crystal display device own are luminous, so in above-mentioned such purposes, use with luminescent lamp to be the employing of light source transmission-type liquid crystal display element backlight always.In addition, in the equipment that adopts reflection type liquid crystal display element, light is as the radiation source from the front before the use that also has.

Along with the electrochemical trend of lightweight, slimming, high brightnessization, low consumption of LCD, backlight with luminescent lamp also to the development of tubuleization, thin-walled property.The tubuleization of luminescent lamp, thin-walled property cause the decline of physical strength, and having in addition because of improving luminous efficiency increases the tendency of the thermal value of lamp, therefore need have higher physical strength, stable on heating glass.

Based on background so, in order to ensure being higher intensity of soft glass and thermotolerance than used in the past plumbous sodium, adopted borosilicic acid is the exploitation of the luminescent lamp of hard glass always, and makes it commercialization.Potted line as electrode uses kovar alloy or tungsten, has developed the pyrex that can carry out the low bulk of air-tight packaging with these metals.Herein, so-called " kovar alloy " is meant that Fe-Ni-Co is the trade name of the Westinghouse Ele.Corp. company of alloy, also comprises the system KOV of Toshiba other equal company's goods such as (trade(brand)names).

The pyrex of this low bulk is the glass of the common employing used as in the past xenon flash lamp of migrating.In purposes is under the situation of xenon flash lamp, and in order to make the flash of light of glass ability lamp, be designed to can transmission ultraviolet ray to a certain degree.But, in purposes is under the situation of luminescent lamp, must consider to prevent the countermeasure that ultraviolet ray is sewed, or consider because of occurring in the glass variable color that the interior ultraviolet irradiation of lamp causes, the countermeasure of promptly so-called " ultraviolet ray is tanned by the sun ", thereby using always and adding the glass that can improve the composition of these characteristics on a small quantity.

Disclosed glass in patent documentation 1 or the patent documentation 2 is the representational example of the glass in this purposes, is by based on pyrex, contains TiO ₂, PbO, Sb ₂O ₃In any, improved the composition of the tanning by the sun property of UV resistant of glass thus.In addition, disclosed glass in patent documentation 3 or the patent documentation 4 is by further interpolation Fe ₂O ₃, CeO ₂, the ultraviolet transmittance of the 253.7nm of the resonance line of mercury is suppressed at low-level composition.

The manufacturing process of the Glass tubing during as batch process has floating method, dimension sieve (Vello) method, Dan Na (Danner) method etc., and the Glass tubing that is used for backlight is a tubule, because demanding dimensional precision, so the most suitable employing danner process.

As the fluorescent lamp for lighting of representing as liquid crystal with element etc., especially in recent years be used for large-scale liquid crystal TV with or the characteristic of the backlight of the watch-dog of band TV etc., along with the increase of per unit lamp usage quantity, the long sizeization of lamp, following project is required higher characteristic now.

Principle of luminosity with luminescent lamp backlight and general lighting excite the mercury vapor of generation to penetrate ultraviolet ray with identical by interelectrode discharge, and it is ultraviolet and visible rays takes place to be coated in fluorescent substance acceptance on the inside pipe wall face.In lamp, the ultraviolet ray of 253.7nm wavelength mainly takes place, wherein major part is transformed into visible rays, but some can not be carried out the visible light conversion by fluor sometimes, can arrive glass.

In luminescent lamp, though to compare luminous intensity lower with 253.7nm, also exist except that this wavelength 297,313,334, the ultraviolet ray of 366nm wavelength.Therefore, need to consider the ultraviolet of this wavelength covered.

With backlight, because the radical of luminescent lamp is to use several in each equipment to more than 10, therefore total ultra violet radiation amount also must increase for liquid crystal TV.

With the liquid crystal TV purposes is the center, as in order to improve the improvement of the desired brightness of back lighting device, will improve the characteristic of lamp itself certainly, but also accounts for suitable proportion as the improvement of the resin material of light guiding plate or speculum.The resins such as polyester, polystyrene, polypropylene, polycarbonate film or cyclic olefin polymer that are used for such light guiding plate or speculum, owing to can not fully have the UV resistant characteristic, the deterioration wavelength is especially arranged near 300～330nm, therefore, will descend or become the reason that makes product life, reliability decrease as the display quality of back lighting device if be exposed under the ultraviolet ray of this wavelength.Therefore, also need to take to absorb the ultraviolet ray of described wavelength zone, prevent its countermeasure to the outside radiation of lamp with glass.

Be used at pyrex that will be in the past under the situation of the outer tube with luminescent lamp backlight, take the following measure of Denging: reflecting or absorb ultraviolet composition in the coating of Glass tubing inner face is Al ₂O ₃, TiO ₂, ZnO etc., be coated with fluor then thereon, form multilayer film, weaken the ultraviolet intensity that arrives glass.But, thin footpathization or the long sizeization of aforesaid method because of following Glass tubing, it is difficult that coating becomes, and perhaps owing to need to increase painting process, causes cost to rise inevitably.

In addition, also require the characteristic of ultraviolet anti-tanning by the sun property excellence or the thermal expansivity of Glass tubing are fit to the importing metal, this is necessary item keeping backlight with on the characteristic of Glass tubing as everyone knows.

Above-mentioned patent documentation 1 disclosed glass, has tanning by the sun property of UV resistant and to the ultraviolet sufficient screening effect of 253.7nm, but do not take into full account the ultraviolet cutoff of the 315nm corresponding, have through making the misgivings of internal resin deterioration after using for a long time with the resin deterioration that is used for back lighting device.

Above-mentioned patent documentation 2,3,4 disclosed glass are by combination WO ₃, ZrO ₂, SnO ₂, Fe ₂O ₃, CeO ₂, adjusted the ultraviolet cutoff characteristic, but the characteristic of these both sides of increased devitrification resistance in can not say so the ultraviolet cutoff characteristic that fully satisfies 315nm and 2 processing has Fe ₂O ₃, CeO ₂, TiO ₂Mutually strengthen painted tendency, the absorption characteristic that has a 315nm by the glass melting state about, ultraviolet absorption limit problem of unstable.In addition, especially contain CeO ₂Glass owing to produce to absorb at visible area easily, therefore be not suitable for requiring the liquid crystal TV of good brightness and colorrendering quality to use.

Patent documentation 1: the spy opens flat 9-110467 communique

Patent documentation 2: the spy opens the 2002-187734 communique

Patent documentation 3: the spy opens the 2002-293571 communique

Patent documentation 4: the spy opens the 2004-91308 communique

Summary of the invention

The present invention considers that above various situations propose, its purpose is, a kind of glass of using the Glass tubing of luminescent lamp backlight that is suitable as is provided, especially to below the wavelength 315nm to influential harmful ultraviolet the covering property excellence of resin deterioration, have good tanning by the sun property of UV resistant as the luminescent lamp purposes.

For addressing the above problem, a mode of the present invention provides a kind of fluorescent-lamp-use ultraviolet absorbing glass, it is characterized in that, and be that glass constitutes by borosilicic acid, this borosilicic acid is that glass contains 0.001～0.05% Fe2O3,0.1～5% CeO by quality % ₂, 0.01～5% SnO+SnO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅, and the average coefficient of linear expansion of 0～300 ℃ of scope stipulating among the JIS R3102 is 36～57 * 10 ^-7/ ℃; Described ultraviolet absorbing glass is 315nm at wavelength, the transmissivity when wall thickness is 0.3mm is below 10%, impairment grade in following ultraviolet radiation test is below 5%, wherein, impairment grade in the described ultraviolet radiation test, be will to the two sides carried out the minute surface optical grinding the abrasive surface of thick glass for 1mm to be configured in from predominant wavelength to ground relatively be on the position of 400W high pressure mercury vapour lamp 20cm of 253.7nm, after having shone ultraviolet ray in 300 hours, measuring wavelength is the transmissivity (T at 400nm place ₁), and the wavelength that utilizes following formula to obtain before uviolizing is the initial stage transmissivity (T at 400nm place ₀) beginning impairment grade.

Impairment grade (%)=[(T ₀-T ₁)/T ₀] * 100

Described borosilicic acid is that glass is characterised in that, contains 60～80% SiO by quality % ₂, 1～7% Al ₂O ₃, 10～25% B ₂O ₃, 3～15% Li ₂O+Na ₂O+K ₂O, 0～5% CaO+MgO+BaO+SrO.

In addition, another way of the present invention is described fluorescent-lamp-use ultraviolet absorbing glass can be molded into tubulose.In addition, the external diameter of Glass tubing is 0.7～6mm, and wall thickness is 0.07～0.7mm, is preferred for the back light of liquid crystal indicator.

In addition, another mode of the present invention is a kind of manufacture method of fluorescent-lamp-use ultraviolet absorbing glass, wherein, described fluorescent-lamp-use ultraviolet absorbing glass is that glass constitutes by borosilicic acid, this borosilicic acid is that glass uses the raw materials of compound of divalent as the Sn source, with frit fusion under reductibility, and contain 0.001～0.05% Fe2O3,0.1～5% CeO by quality % ₂, 0.01～5% SnO+SnO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅As herein borosilicic acid is glass, preferably above-mentioned 60～80% the SiO that contains ₂, 1～7% Al ₂O ₃, 10～25% B2O3,3～15% Li ₂O+Na ₂O+K ₂The glass of O, 0～5% CaO+MgO+BaO+SrO.

In addition, another mode of the present invention is a kind of manufacture method of fluorescent-lamp-use ultraviolet absorbing glass, wherein, described fluorescent-lamp-use ultraviolet absorbing glass is that glass constitutes by borosilicic acid, this borosilicic acid is that glass is with frit fusion under reductibility, and contains 0.001～0.05% Fe by quality % ₂O ₃, 0.1～5% CeO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅As herein borosilicic acid is glass, preferably above-mentioned 60～80% the SiO that contains ₂, 1～7% Al ₂O ₃, 10～25% B ₂O ₃, 3～1 5% Li ₂O+Na ₂O+K ₂The glass of O, 0～5% CaO+MgO+BaO+SrO.

The fluorescent-lamp-use glass of a mode of the present invention, owing to have and the matched thermal expansivity of the sealing of kovar alloy and tungsten, and has excellent a tanning by the sun property of UV resistant, so be suitable as the fluorescent-lamp-use Glass tubing, especially be suitable as the backlight of display unit such as liquid-crystal display with the used Glass tubing of luminescent lamp.

In addition, the glass of a mode of the present invention, because the ultraviolet cutoff characteristic at 315nm place is also excellent, even therefore use under the situation of luminescent lamp the backlight of display unit such as being used for liquid-crystal display, also can not make the material deterioration of the resin component etc. of display unit inside, can improve the reliability of display unit.

In addition, adopt the glass of a mode of the present invention and the fluorescent-lamp-use Glass tubing made, because tanning by the sun property of UV resistant height, so can prevent to result from the deterioration of display quality of the liquid-crystal display etc. of glass variable color.

Embodiment

The present invention realizes described purpose by above-mentioned formation, below aforesaid qualification is constituted each composition of glass of the present invention the reason of content etc. describe.

Fe ₂O ₃Be to absorb ultraviolet composition, be just can expect obligato composition in an embodiment of the invention of ultraviolet cutoff effect by a small amount of interpolation powerfully, if but be lower than 0.001% by quality %, can not expect its effect.In addition, surpass 0.05%, tanning by the sun property of UV resistant is had a negative impact if add.Thereby be preferably 0.003～0.04%, more preferably 0.005～0.03%.

CeO ₂Be to absorb ultraviolet composition, be the essential composition of an embodiment of the invention powerfully, if but owing to be lower than 0.1% by quality %, then do not cover ultraviolet effect, if it is not surpass 5%, then preferred because increased devitrification resistance increases.Because CeO ₂Oxidizing power strong, so himself be reduced, be the state of 3 valencys easily, but in simple glass with Ce ³⁺And Ce ⁴⁺State coexistence, Ce ³⁺Has absorption band at 316nm, Ce ⁴⁺Has absorption band at 243nm.With respect to Ce ³⁺Demonstrate sharp-pointed absorption, because Ce ⁴⁺The wide cut that demonstrates visible area absorbs, if therefore increase its addition, then glass can be coloured to tawny.For the flint glass that is used in visible area and does not have to absorb absorbs ultraviolet ray below the 315nm expeditiously, need to improve Ce ³⁺Ratio, using CeO ₂Situation under, preferably make glass melting have reductibility.

SnO+SnO ₂It is the necessary composition of control Ce ionic valence mumber.The Sn ion exists with the state of divalent or 4 valencys in glass.With CeO ₂Under the situation of coexistence, because of CeO ₂Oxidizing power make the Sn ion be the state of 4 valencys, the Ce ion is reduced itself, is the state of 3 valencys easily, can absorb ultraviolet ray effectively.Sn preferably uses with the form of the such divalent compound of SnO, but since oxidized in glass, SnO become ₂Form, so use SnO+SnO ₂Expression.Sn uses by the form with the compound of divalent, can be used as effective reductive agent and plays a role.As reductive agent, also can use the such organic system raw material of carbon, but the organic system reductive agent is gaseous phase by playing a role as reductive agent, owing in melting process, from glass, volatilize, so can not remain in the end article.In melting process, after the decomposition of organic system reductive agent, volatilization, the redox state of glass depends on fusion atmosphere, if under the long-time situation of being detained, be difficult to keep reductibility in tank furnace.SnO is residual as glass ingredient, also has the effect that makes ionic valence mumber stabilization in glass, in an embodiment of the invention, and SnO+SnO ₂Be essential composition.If SnO+SnO ₂Both total amounts are lower than 0.01%, then Ce ⁴⁺Ratio increase, glass coloring becomes tawny, the transmissivity of visible area descends.In addition, if surpass 5%, then not preferred because the tendency towards devitrification of glass strengthens.In addition, SnO+SnO ₂Except effect, also has the ultraviolet effect of absorption with control Ce ionic valence mumber.The Ce ion makes Ce by reduction ³⁺Increase Ce ⁴⁺Reduce.Herein, SnO+SnO ₂With Sn ²⁺And Sn ⁴⁺State coexist as in the glass Sn ²⁺Near 240nm, has absorption band.Therefore, can pass through Sn ²⁺Replenish because Ce ⁴⁺The reduction of the ultraviolet radiation absorption characteristic of the 253.7nm that reduces and cause.

By adding SnO+SnO ₂The manufacture method that makes fusion have reductibility is the prominent feature of an embodiment of the invention, even but do not contain the composition of SnO, adopt other method also might make fusion have reductibility.Specifically, be organic reducing agents such as ammonium salt by interpolation carbon or sucrose etc. in raw material, or the control of consideration fusion atmosphere etc., carry out the fusion under such reductibility, Ce ionic valence mumber can be formed Ce ³⁺State.Also can replace SnO+SnO with above-mentioned reductive agent ₂A part, also can both and use.But, such as mentioned above under the situation of using the organic system reductive agent, be disadvantageous for ionic valence mumber stabilization, needing increases addition etc., and condition is noted.If especially owing to increase Ce ⁴⁺Ratio, then glass can be coloured to tawny, the transmissivity of 400nm descends, it is important therefore keeping reductibility.Is that the sample of 1mm is that the transmissivity at 400nm place is a yardstick at wavelength to the evaluation of glass coloring to be ground to wall thickness.As long as its value is more than 88%, preferably more than 89%, more preferably more than 90%, then glass painted reaches visual detectable hardly level, do not influence the brightness of luminescent lamp.

Improve Ce by interpolation or the reductibility fusion that utilizes SnO ³⁺Ratio, can obtain effective ultraviolet radiation absorption characteristic, but think and be difficult to make the Ce ion to become the state of 3 valencys fully, a part is with Ce ⁴⁺State remaining.Because Ce ⁴⁺Also be the xanchromatic coloring components,, also can make glass coloring become light yellow therefore according to Ce ionic state difference.Preferred over-drastic is painted, but if light color painted can be corrected corresponding by color.In color is corrected, can use CoO, NiO, Nd ₂O ₃, MnO ₂Deng, because these compositions are powerful tinting materials, therefore preferred excessively interpolation, the upper limit is defined as 1%.

ZrO ₂, ZnO, Nb ₂O ₅Be the effective constituent that improves tanning by the sun property of UV resistant, by quality %, its total amount need be more than 0.01%, if but above 5%, because of increased devitrification resistance improves not preferred.These compositions can add separately, also can add more than 2 kinds, but use Nb ₂O ₅Situation under, in order to prevent glass coloring, Nb ₂O ₅On be limited to 0.2%.

The average coefficient of linear expansion of glass is defined as 36～57 * 10 ^-7/ ℃ scope, be in order to obtain the matching with the thermal expansion that becomes the kovar alloy of electrode material or tungsten, to improve stopping property.The preferable range of each electrode material is, is to be 36～46 * 10 under the situation of tungsten at electrode materials ^-7/ ℃, be 46～57 * 10 under the situation that is kovar alloy ^-7/ ℃, if surpass this scope, then stopping property worsens.

As mentioned above, penetrate, then can impel the material deterioration of the resin component etc. of LCD display unit inside, become the major cause that reduces product life or reliability if ultraviolet ray transmitting glass Guan Erxiang pipe is outer.Therefore, in an embodiment of the invention, making it have the ultraviolet cutoff characteristic by mentioned component, is under the state of 0.3mm at glass to wall thickness by optical grinding, is that the ultraviolet transmittance at 315nm place is set in below 10% with wavelength.Therefore, with glassy phase ratio in the past, the ultraviolet ray of the 313nm of ejaculation outside pipe can be reduced by 8 one-tenth～9 one-tenth degree.

In addition, in an embodiment of the invention, the reasons are as follows of the impairment grade in aforesaid definite ultraviolet radiation test.Generally, near the intensive ultraviolet source in the accelerated test of exposure glass, can confirm painted tendency (whether being easy painted glass) by 1 hour～several hours, if but above 100 hours, its degree gradual slow can confirmed the roughly state of approaching painted gauge of tanning by the sun through 300 hours the moment.Therefore, the influence that the transmissivity in the time of can more correctly holding long-time use of actual product descends.The decline of tanning by the sun the painted transmissivity that causes if this variation relates to visible area, then can produce detrimentally affect to the brightness of lamp in ultraviolet portion maximum.Especially owing to can think near the violaceous minute light energy distribution that 400nm, has luminescent lamp, and because of tanning by the sun the transmissivity deterioration that causes is the easiest to influence brightness, therefore with the transmissivity at wavelength 400nm place yardstick as evaluation.If the impairment grade of the transmissivity in the test under this condition is below 5%, can be suppressed at the degree that the user can not discern with resulting from the scotopiaization that the LCD of fluorescent-lamp-use Glass tubing shows, can keep practical display quality.

In addition, an embodiment of the invention are characterised in that, described pyrex contains 60～80% SiO by quality % ₂, 1～7% Al ₂O ₃, 10～25% B ₂O ₃, 3～15% Li ₂O+Na ₂O+K ₂O, 0～5% CaO+MgO+BaO+SrO, the below reason that as mentioned above content of each composition limited of explanation.

SiO ₂Be the one-tenth net composition of glass, if but surpass 80%, then glass melting, plasticity worsen, if be lower than 60%, then the chemical durability of glass descends.The reason that is declined to become wind erosion, browning etc. of chemical durability, and become the brightness decline of luminescent lamp, the reason of generation look inequality.Thereby be preferably 62～78%.

Al ₂O ₃Have the increased devitrification resistance of improving glass and the effect of chemical durability, if but surpass 7%, because of striped etc. takes place meltbility is worsened.If be lower than 1%, phase-splitting or devitrification then take place easily, the chemical durability of glass also descends.Thereby be preferably 2～5% scope.

B ₂O ₃Be the composition that adopts in order to improve meltbility and adjustment viscosity, its volatility is very high, if content surpasses 25%, then seldom arrives the glass of homogeneous.In addition, if content is lower than 10%, then meltbility worsens.Thereby be preferably 12～20%.

Li ₂O, Na ₂O, K ₂O plays a role as flux, is to be used to improve glass melting, to adjust the composition of viscosity, thermal expansivity simultaneously, but does not have effect under the situation that can not satisfy above-mentioned content separately, surpassing under its situation of higher limit, thermal expansivity is excessive, in addition, and deteriorates chemical durability.The content of each composition, % is preferably Li by quality ₂O is 0～3%, Na ₂O is 0～8%, K ₂O is 2～12%, compares with independent interpolation, by containing 2 kinds or 3 kinds, can expect to obtain owing to mixed base the effect of insulativity raising etc.Surpass under the situation of each higher limit at each content, thermal expansivity is excessive, or makes deteriorates chemical durability.In addition, in the bright lamp of luminescent lamp, known Na ₂O and mercury reaction form amalgam, and the result is Na superfluous in the glass ₂O can reduce the amount of mercury that acts on effectively in luminescent lamp, the environmental of Cong Xiao Minus mercury usage quantity is considered, also preferred Na ₂O add to surpass above-mentioned higher limit, and more preferably 0～4%.In addition, when being used for the purposes that seals with kovar alloy, be preferably 8～15%, when being used for the purposes that seals with tungsten, be preferably 3～10%.If be lower than each lower value, then, therefore can not form good sealing with kovar alloy or tungsten because the coefficient of expansion reduces significantly, and viscosity rises significantly.

CaO, MgO, BaO, SrO are the compositions that has viscosity when reducing glass high temperature, improves the effect of meltbility, can add 5% in total amount as required.Surpass higher limit if add, then the vitreousness instability is easy to generate devitrification.

In an embodiment of the invention, use during glass melting limpid dose limpid dose of reductibility preferably.The feature of an embodiment of the invention is, by will be as the CeO of UV light absorber ₂Be controlled at Ce ³⁺The ionic state can obtain good ultraviolet radiation absorption characteristic, preferably do not adopt oxidisability limpid dose.Based on same reason, also should avoid using the raw material of having an effect as oxygenant.Specifically, as limpid dose, preferably NaCl or Na ₂SO ₄+ C does not preferably use Sb ₂O ₃, As ₂O ₃In addition, also should not use the nitrate etc. of alkaline components.

In addition, penetrate, will impel the material deterioration of the resin component etc. of LCD display unit inside, become the reason that reduces product life or reliability if ultraviolet ray transmitting glass Guan Erxiang pipe is outer as mentioned above.Therefore, in an embodiment of the invention, make it have the ultraviolet cutoff characteristic by the mentioned component composition, glass optics is being ground under the state of wall thickness 0.3mm, the ultraviolet transmittance at wavelength 315nm place is below 10%.If under the situation that does not influence visual optical transmission, seek preferred quality level,, be under the situation of 0.3mm then at wall thickness by adjusting trace ingredients etc., also can be below 1%.

The glass of an embodiment of the invention can be made in the following manner.At first, reach the mode weighing raw material and the mixing of above-mentioned compositing range with resulting glass.This raw mix is housed in quartz crucible or the platinum crucible, in the fusion of electric furnace internal heating.fully stir, limpid after, be configured as desired form.When being configured as tubulose in batches for the fluorescent-lamp-use tubule of making another embodiment of the invention etc., can be shaped without a doubt with danner process, multistage deep-draw known trombone slide manufacturing process such as (redraw) supplying with builder by the forehearth (fore hearth) and the glass that have used the platinum parts with tank furnace fused glass.

Then, describe the glass of an embodiment of the invention in detail based on embodiment.Table 1 illustrates embodiments of the invention and comparative example.Sample No.1～10th, embodiments of the invention, No.11, the 12nd represents the comparative example of glass in the past.Also have, the composition in the table is represented by quality %.The glass of putting down in writing in the table is to come raw material powders such as weighing, the carbonate that mixes silica sand, each metal, nitrate, oxyhydroxide in the mode that reaches each oxide compound composition shown in the table, with the limpid method that has adopted NaCl, adopt quartz crucible 1450 ℃ of following fusions 5 hours.At this moment, with the form importing Sn of divalent compounds such as tin protoxide, but all be converted into SnO in the table ₂Represent.In addition, in No.5,10 the glass by total combined amount than having mixed 2% carbon as reductive agent, and carry out fusion.Thereafter, with fully stir, the glass of limpid mistake flows out in rectangle frame, after slow cooling, in conjunction with assessment item shown below, is processed into the sample of desired shape.

Table 1

	Embodiment										Comparative example
													No.1	No.2	No.3	No.4	No.5	No.6	No.7	No.8	No.9	No.10	No.11	No.12
	SiO 2	66.59	65.05	65.05	65.19	65.48	69.28	65.97	64.49	67.39	68.28	68.55													72.97
B 2O 3													17.3	17.5	19	16.2	18.5	15.5	17	16.8	15	17.2	17.5	17
	Al 2O 3	3	3.5	3.5	2.5	2	3.5	4	3	2.8	3	3.5													3
Li 2O													1	1	1.5	2	0.5	1		0.8	0.7	0.5	1	1
	Na 2O	0.5	0.4	1	0.5	1	0.4	0.7	2.8	0.4	3	0.5													2
K 2O													7.5	7.7	7.7	7	7.2	5.5	6.5	3	7	1.5	7.9	3.5
	MgO					0.1						1
CaO																	0.2	0.1
	BaO								0.1		2.4
SrO																					0.1
	ZrO 2		0.1	0.5	1	0.5	0.2		2	1	0.3
ZnO													2	0.2	1		2.5	1	3		0.5	1.5
	Nb 2O 5	0.1			0.1					0.1
TiO 2																								0.5
	Fe 2O 3	0.01	0.05	0.05	0.01	0.02	0.02	0.03	0.01	0.01	0.02	0.05													0.03
CeO 2													0.8	1.5	0.6	3.5	2	1	0.8	4.5	3	2.3	1
	Sno+SnO 2(SnO 2Convert)	1.2	3	0.1	2.0		2.5	2	2.5	2.0
Glass colour													Colourless	Colourless	Colourless	Colourless	Colourless	Colourless	Colourless	Colourless	Colourless	Colourless	Tawny	Colourless
	The transmissivity of 315nm (%)	3.5	0.2	8.5	<0.1	0.1	1.6	3.3	<0.1	<0.1	<0.1	2.2													75.0
Thermal expansivity (* 10 -7/℃)													49.6	51.8	52.4	51.2	50.5	40.1	40.5	37	38.5	40.2	52	39
	Transmissivity impairment grade (%)	4.1	3.5	4.8	2.8	3.6	1.7	4.2	1.8	3.3	4.1	1.8													0.3

If the project shown in the his-and-hers watches describes, then thermal expansivity is the value that draws according to the average coefficient of linear expansion in 0～300 ℃ of JIS method mensuration.

In order to estimate the stopping property that glass and electrode material can cut down alloy or tungsten, the metallographic phase of the thermal expansivity of preferred glass and electrode material is same or low slightly.If the difference of the thermal expansivity of glass and electrode material is big, will become the reason of leaking or take place crackle from sealing, can not be used as fluorescent-lamp-use.

The impairment grade of the transmissivity that draws by the test of tanning by the sun property of UV resistant, be that each glass sample is cut on one side square tabular for 30mm, will with mode that thickness reaches 1mm carried out two sides optics attrition process sample be placed on the position of mercuryvapour lamp (H-400P) 20cm, after irradiation ultraviolet ray in 300 hours, measure the transmissivity at wavelength 400nm place, the impairment grade of using the initial stage transmissivity before uviolizing to begin is represented.In addition, impairment grade (%)=[(transmissivity after initial stage transmissivity-uviolizing)/initial stage transmissivity] * 100.

In addition, together show the mode that reaches 0.3mm with thickness carried out the two sides optical grinding the measured value of transmissivity of wavelength 315nm of sample.

In each sample of embodiments of the invention No.1～10, No.1～5th, with the sample that the average coefficient of linear expansion of suitable kovar alloy sealing is complementary, No.6～10th, the sample that is complementary with the average coefficient of linear expansion of suitable tungsten sealing.Its average coefficient of linear expansion all is the average coefficient of linear expansion 55 * 10 of comparison near kovar alloy ^-7/ ℃ and the average coefficient of linear expansion 45 * 10 of tungsten ^-7/ ℃ value, can obtain good and sealing that reliability is high.Average coefficient of linear expansion with glass is defined as 36～57 * 10 in an embodiment of the invention ^-7/ ℃ be exactly this cause.

In addition, the transmissivity of the wavelength 315nm during wall thickness 0.3mm is lower than very with glassy phase in the past, and transmission impels harmful ultraviolet ray of resin deterioration hardly.In addition, the transmissivity degradation inhibiting that uviolizing can be caused has very high tanning by the sun property of UV resistant below 5%.

On the contrary, the sample of comparative example No.11 is the example that does not contain the composition of SnO, and the transmissivity at 315nm place is low, and the transmissivity deterioration that causes because of uviolizing is also little, but glass coloring becomes tawny.In addition, the transmissivity deterioration that the sample of No.12 causes because of uviolizing is in low-level, but the transmissivity height at 315nm place, because the ultraviolet ray that can not cover 313nm with Glass tubing, therefore impels the danger of resin component deterioration of backlight apparatus very big.

In addition, the glass of an embodiment of the invention is PbO owing to do not contain environmentally hazardous substance, thereby has the advantage little to the influence of environment.Also have, in the present invention, so-called " not containing in fact " meaning is deliberately not add, but does not get rid of containing of the degree that does not influence desired characteristic that can not sneak into from raw material etc. with keeping away.

As described in detail above, glass of the present invention is suitable as the fluorescent-lamp-use Glass tubing, because the ultraviolet cutoff characteristic is also excellent, even so be used for the backlight of liquid-crystal display etc. with under the situation of luminescent lamp, also can not make the material deterioration of the resin component etc. of display unit inside, can prevent the decline of display quality.In addition, also be not limited to this purposes,, also can be used for the ultraviolet cutoff wave filter owing to have excellent ultraviolet cutoff and visible light transmissivity, simultaneously owing to have high tanning by the sun property of UV resistant, also can be used for mercuryvapour lamp etc. with the peripherals of the light source of ultra violet radiation etc.

Claims (7)

1. a fluorescent-lamp-use ultraviolet absorbing glass is characterized in that, is that glass constitutes by borosilicic acid, and this borosilicic acid is that glass contains 0.001～0.05% Fe by quality % ₂O ₃, 0.1～5% CeO ₂, 0.01～5% SnO+SnO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅, and the average coefficient of linear expansion of 0～300 ℃ of scope stipulating among the JIS R3102 is 36～57 * 10 ^-7/ ℃; The transmissivity at the wavelength 315nm place of described ultraviolet absorbing glass when wall thickness is 0.3mm is below 10%, and the impairment grade in following ultraviolet radiation test is below 5%, wherein,

Impairment grade in the described ultraviolet radiation test is tried to achieve by following method: will to the two sides carried out the minute surface optical grinding wall thickness be that to be configured in from predominant wavelength to ground relatively be on the position of 400W high pressure mercury vapour lamp 20cm of 253.7nm for the abrasive surface of the glass of 1mm, after having shone ultraviolet ray in 300 hours, measure the transmissivity T at wavelength 400nm place ₁, utilize following formula to obtain the initial stage transmissivity T at the wavelength 400nm place before uviolizing ₀The impairment grade of beginning,

Impairment grade (%)=[(T ₀-T ₁)/T ₀] * 100

2. fluorescent-lamp-use ultraviolet absorbing glass as claimed in claim 1 is characterized in that, described borosilicic acid is that glass contains 60～80% SiO by quality % ₂, 1～7% Al ₂O ₃, 10～25% B ₂O ₃, 3～15% Li ₂O+Na ₂O+K ₂O, 0～5% CaO+MgO+BaO+SrO.

3. fluorescent-lamp-use Glass tubing, it is molded into tubulose with each described fluorescent-lamp-use ultraviolet absorbing glass in claim 1 or 2 and forms.

4. fluorescent-lamp-use Glass tubing as claimed in claim 3 is characterized in that, the external diameter of described Glass tubing is 0.7～6mm, and wall thickness is 0.07～0.7mm, is used for the back light of liquid crystal indicator.

5. the manufacture method of a fluorescent-lamp-use ultraviolet absorbing glass, wherein, described fluorescent-lamp-use ultraviolet absorbing glass is that glass constitutes by borosilicic acid, this borosilicic acid is that glass uses the raw materials of compound of divalent as the Sn source, with frit fusion under reductibility, and contain 0.001～0.05% Fe by quality % ₂O ₃, 0.1～5% CeO ₂, 0.01～5% SnO+SnO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅

6. the manufacture method of a fluorescent-lamp-use ultraviolet absorbing glass, wherein, described fluorescent-lamp-use ultraviolet absorbing glass is that glass constitutes by borosilicic acid, and this borosilicic acid is that glass is with frit fusion under reductibility, and contains 0.001～0.05% Fe by quality % ₂O ₃, 0.1～5% CeO ₂, 0.01～5% ZrO ₂+ ZnO+Nb ₂O ₅

7. as the manufacture method of each described fluorescent-lamp-use ultraviolet absorbing glass in claim 5 or 6, it is characterized in that described borosilicic acid is that glass contains 60～80% SiO ₂, 1～7% Al ₂O ₃, 10～25% B ₂O ₃, 3～15% Li ₂O+Na ₂O+K ₂O, 0～5% CaO+MgO+BaO+SrO.