JPH0139190B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a fluorescent lamp having a transparent conductive coating on the inner surface of a glass tube, a so-called rapid-start type fluorescent lamp.
The present invention relates to measures for lowering the discharge starting voltage.

Rapid-start fluorescent lamps are lamps that are designed so that they can be started immediately at relatively low circuit voltages by providing suitable starting aids in the lamp itself and using a ballast with an electrode preheating circuit. . As a starting aid, a transparent conductive coating (commonly known as Nesa film) is provided on the inner surface of the glass tube.

Such rapid-start fluorescent lamps typically operate without the use of a glow starter, which is required to start fluorescent lamps commonly used in households. Therefore, when this fluorescent lamp is used in department stores, buildings, schools, etc., advantages such as extremely easy maintenance can be obtained.

Incidentally, in recent years, a wave of energy saving has been spreading to the lighting field, and fluorescent lamps that save energy are being actively developed.
This energy-saving fluorescent lamp uses a mixed rare gas containing krypton gas, which has a larger molecular weight, as the main component, instead of argon gas, which has been commonly used in the past. Representative examples of this enclosed rare gas include krypton-argon and krypton-neon mixed gas.
Energy-saving fluorescent lamps filled with these gases are being put into practical use. By using such a mixed rare gas containing krypton gas as the main component as the filler gas, for example, in a 40 watt type fluorescent lamp, maximum lamp efficiency can be obtained when krypton gas: neon gas = 75:25. At this time, the lamp power was reduced from 40 watts to 35 watts, resulting in a fluorescent lamp with approximately 10% power savings.

As a natural consequence, it is necessary to save power even in the above-mentioned rapid start type fluorescent lamp, and efforts are being made to save power.

However, the rapid-start fluorescent lamp filled with the rare gas mixture mainly composed of krypton gas developed in this way cannot be attached to a conventional device equipped with a ballast for rapid-start fluorescent lamps. When we conducted lighting experiments, we found that a large number of lamps did not turn on, and that it was particularly difficult to turn them on at low ambient temperatures. When the cause of this was investigated, it was found that the discharge starting voltage of such rapid start type fluorescent lamps is extremely high.

In particular, lamps that use a phosphor with a high color rendering property to improve the color rendering properties of such power-saving rapid-start fluorescent lamps have become even more difficult to light. It was found that the discharge starting voltage was further increased in this case as well.

Therefore, an object of the present invention is to provide a rapid start type fluorescent lamp which can be easily lit with any filler gas composition and any type of phosphor by reducing the discharge starting voltage. It's about doing.

In order to achieve the above object, in the present invention,
A glass tube with electrodes at both ends and with appropriate amounts of mercury and inert gas sealed inside, a transparent conductive coating provided on the inner surface of this glass tube, and a phosphor provided on this coating. In a rapid start type fluorescent lamp comprising a coating, at least one phosphor selected from the group consisting of barium titanate, lead titanate, and lead/barium titanate is contained in the phosphor constituting the phosphor coating. It is characterized in that 0.1 to 3% by weight of the substance is added to the phosphor.

Owing to the characteristic structure of the present invention, it has become possible to significantly reduce the discharge starting voltage of a rapid start type fluorescent lamp having a transparent conductive coating on the inner surface. As a result, rapid-start fluorescent lamps with any fill gas composition and phosphor, especially those with krypton-based fill gases, which tend to have higher firing voltages, are Even if it is a power type rapid start type fluorescent lamp or a high color rendering power saving type rapid start type fluorescent lamp with improved color rendering properties, it is stable for a conventional rapid start type fluorescent lamp. By attaching it to a device with a container, it became possible to reliably light the lamp.

That is, the present invention improves the discharge starting voltage of a rapid-start type fluorescent lamp having a transparent conductive coating on the inner surface by using one of barium titanate, lead titanate, lead/barium titanate, or a mixture thereof. This is achieved by adding a predetermined amount to the phosphor. However, the mechanism as to why these substances can lower the discharge starting voltage of a rapid-start type fluorescent lamp having a Nesa film is currently unknown.

Hereinafter, the present invention will be explained in more detail using Examples.

Example 1 A transparent conductive coating made of tin oxide (SnO ₂ ) was uniformly provided on the entire inner surface of ten straight 40-watt glass tubes, a phosphor coating was uniformly applied on the coating, and the coating was dried and dried. Fire. The phosphor used is Sb or Sb, Mn-activated halophosphate phosphor 85% by weight.
It has high color rendering properties and consists of 14% by weight of Eu ³⁺ -activated yttrium oxide and 1% by weight of Mn-activated zinc silicate. Then, after sealing the mounts at both ends and exhausting the air, the exhaust pipe is tipped off by filling with an appropriate amount of mercury and inert gas. The inert gas used has a composition of Kr:Ne=75:25, which is suitable for power saving. Thereafter, a rapid start type fluorescent lamp is completed by attaching caps to both ends.
The fluorescent lamp manufactured in this way is a rapid-start type fluorescent lamp with high color rendering properties and low power consumption, and the average value of the discharge starting voltage is
It was 196 volts.

Next, barium titanate (BaTiO ₃ ), lead/barium titanate (Ba _0.5 Pb _0.5 TiO ₃ ), and lead titanate (PbTiO ₃ ) were added to the phosphor of the lamp described above, and Ten lamps each with varying amounts of discharge were produced, and the average value of each discharge starting voltage was determined. The first graph shows how many volts the average value of this discharge starting voltage has decreased compared to the average value of the firing voltage of a lamp without any addition to the phosphor (i.e., a conventional lamp). It is a diagram. In other words, Figure 1 is
The graph shows the relationship between the amount of each of BaTiO ₃ , Ba _0.5 Pb _0.5 TiO ₃ , and PbTiO ₃ added and the decrease in discharge starting voltage. In the figure, straight line 1 shows the relationship between the amount (wt%) of BaTiO ₃ added to the phosphor and the decrease in discharge starting voltage (volts). As is clear from straight line 1, as the amount of BaTiO ₃ added to the phosphor increases, the decrease in the firing voltage increases linearly. In other words, this means that the discharge starting voltage of a rapid start type fluorescent lamp can be arbitrarily controlled by the amount of BaTiO ₃ added.

Straight line 2 shows the relationship between the addition (wt%) and the decrease in discharge starting voltage (volts) when PbTiO ₃ is added to the phosphor. As is clear from straight line 2, adding to the phosphor
As the amount of PbTiO ₃ increases, the decrease in discharge starting voltage increases linearly, and this trend is almost the same as in the case of BaTiO ₃ shown by straight line 1. However, the effect of lowering the discharge starting voltage is
_BaTiO3 is better than _PbTiO3 .

Straight line 3 shows the relationship between the amount (wt%) of _{Ba0.5Pb0.5TiO3} , which is a compound of BaTiO3 _{and PbTiO3} , added to _{the phosphor} and the decrease in discharge starting voltage (volts). It is something that straight line 3
As is clear from the graph, Ba _0.5 added to the phosphor
As the amount of Pb _0.5 TiO ₃ increases, the drop in discharge starting voltage increases linearly, and this trend is almost the same as in the case of BaTiO ₃ and PbTiO ₃ shown in straight lines 1 and 2. ing. It can be seen that the effect of lowering the discharge starting voltage is approximately intermediate between BaTiO ₃ and PbTiO ₃ . This tendency remained almost the same even when the ratio of replacing part of Ba with Pb in BaPbTiO ₃ was changed. Although not shown, a mixture of BaTiO ₃ and PbTiO ₃ ,
Mixture of _BaTiO3 and _BaPbO3 , _PbTiO3 and
Mixture with _BaPbTiO3 , _BaTiO3 and _PbTiO3
Regarding mixtures with BaPbTiO ₃ , lamps were fabricated by varying the mixing ratio and substitution ratio, and the addition amount was varied, and the reduction in the discharge starting voltage was determined. As a result, it was found that in any of these combinations, the decrease in the discharge starting voltage existed within the region surrounded by straight lines 1 and 2 shown in FIG. These experimental results are
This shows that the discharge starting voltage of a rapid-start fluorescent lamp can be controlled arbitrarily by adding at least one substance selected from the group consisting of BaTiO ₃ , PbTiO ₃ , and BaPbTiO ₃ to the phosphor. .

However, further experiments revealed that when the above-mentioned substance was added to the phosphor, the luminous flux decreased as the amount added increased. FIG. 2 is a graph showing the relationship between the amount of each of BaTiO ₃ , Ba _0.5 Pb _0.5 TiO ₃ , and PbTiO ₃ added and the luminous flux reduction rate. Here, the luminous flux reduction rate is defined as follows. That is, when the 0-hour luminous flux of a fluorescent lamp with an additive amount of zero is set to 100, the 0-hour luminous flux of a fluorescent lamp with addition is performed is determined, and this difference is referred to as the luminous flux reduction rate. Now, the straight line 4 shows the relationship between the amount (% by weight) of BaTiO ₃ added to the phosphor and the luminous flux reduction rate (%). As is clear from straight line 4, as the amount of BaTiO ₃ added to the phosphor increases, the luminous flux reduction rate increases linearly. In other words, this shows that by increasing the amount of BaTiO ₃ added, the discharge starting voltage of the rapid-start type fluorescent lamp can be significantly lowered, but on the other hand, the luminous flux reduction rate also increases.
This tendency is almost the same in the cases of PbTiO ₃ shown by straight line 5 and Ba _0.5 Pb _0.5 TiO ₃ shown by straight line 6. Although not shown, a mixture of these substances also shows a similar tendency. Normally, it is desirable that this luminous flux reduction rate be within 10%, and for this purpose, the practical upper limit of the amount added must be 3% by weight or less. Moreover, its practical lower limit is the amount necessary to reduce the discharge starting voltage, that is, 0.1%. That is,
In order to suppress the luminous flux reduction rate below a value that does not pose a practical problem and reduce the discharge starting voltage, the optimum addition amount range is 0.1 to 3% by weight.

Example 2 A 40W rapid start type cell was manufactured by providing a transparent conductive film made of SnO ₂ on the inner surface of a glass tube, and providing an Sb- and Mn-activated calcium halophosphate phosphor film on the inner surface of the glass tube, and using argon gas as the filler gas. A light lamp was made. The average firing voltage of this lamp was 153 volts. On the contrary,
When BaTiO ₃ was added to this phosphor and the amount added was varied, the drop in discharge starting voltage increased linearly in proportion to the amount added, and the discharge when the amount added was 3% by weight. The average starting voltage was 148 volts. That is, by adding 3% by weight of BaTiO ₃ , the firing voltage can be lowered by 5 volts compared to a lamp without additives.

Example 3 A transparent conductive coating made of SnO ₂ was provided on the inner surface of a glass tube, and an Sb- and Mn-activated calcium halophosphate phosphor coating was provided on top of the transparent conductive coating, and a gas composition of krypton gas: neon gas = 75:25 was used as the sealed gas. A 40 watt rapid start type fluorescent lamp was fabricated using the same. The average firing voltage of this lamp was 159 volts. On the contrary,
When PbTiO ₃ was added to this phosphor and the amount added was varied, the drop in discharge starting voltage increased linearly in proportion to the amount added, and the discharge when the amount added was 2% by weight. The average starting voltage was 151 volts. That is, by adding 2% by weight of PbTiO ₃ , the firing voltage can be lowered by 8 volts compared to a lamp without additives.

Example 4 A transparent conductive film made of SnO ₂ was provided on the inner surface of a glass tube, and on top of that, 13% by weight of Sb and Mn-activated halophosphate phosphor and 35% by weight of Sb-activated halophosphate phosphor.
Weight%, Mn-activated zinc silicate phosphor 3% by weight,
A phosphor coating consisting of 44% by weight of Sn-activated strontium/zinc orthophosphate phosphor and 5% by weight of Mn-activated germanate phosphor is provided, and the enclosed gas is krypton gas: neon gas = 75:25. A 40 watt high color rendering rapid start type fluorescent lamp was fabricated using a gas composition of: The average value of the discharge starting voltage of this lamp is
It was 169 volts. On the other hand, when we added a mixture of BaTiO ₃ and PbTiO ₃ to this phosphor and varied the amount and mixing ratio, the drop in discharge starting voltage increased linearly in proportion to the amount added. The average value of the discharge starting voltage was 160 volts when the additive amounts were 1% by weight of BaTiO ₃ and 1% by weight of PbTiO ₃ .

Example 5 A transparent conductive coating made of SnO ₂ was provided on the inner surface of the glass tube, and on top of that, 15% by weight of Eu ²⁺ activated aluminate blue phosphor and 40% by weight of Tb ³⁺ activated aluminate green phosphor. , and a mixed phosphor coating consisting of ⁴⁵ wt.
A rapid-start type fluorescent lamp was manufactured. The average discharge starting voltage of this lamp is 180
It was hot with bolts. On the other hand, this phosphor
When BaTiO ₃ was added and the amount added was varied, the decrease in the discharge starting voltage increased linearly in proportion to the amount added, and the average value of the starting voltage when the amount added was 2% by weight. was 162 volts.

Example 6 A transparent conductive film made of SnO ₂ was provided on the inner surface of the glass tube, and on top of that, 15% by weight of Eu ²⁺ activated aluminate blue phosphor and 40% by weight of Tb ³⁺ activated aluminate green phosphor. , and a mixed phosphor coating consisting of ⁴⁵ wt.
A rapid-start type fluorescent lamp was manufactured. The average discharge starting voltage of this lamp is 180
It was hot with bolts. On the other hand, this phosphor
When PbTiO ₃ was added and the amount added was varied, the decrease in the discharge starting voltage increased linearly in proportion to the amount added, and the average value of the starting voltage when the amount added was 2% by weight. was 165 volts.

Example 7 A transparent conductive film made of SnO ₂ was provided on the inner surface of a glass tube, and on top of that, 85% by weight of Sb or Sb, Mn-activated halophosphate phosphor, 14% by weight of Eu-activated yttrium oxide phosphor, A mixed phosphor coating consisting of 1% by weight of Mn-activated zinc silicate phosphor and Mn-activated zinc silicate phosphor was provided, and a gas composition of krypton gas: argon gas = 75:25 was used as the sealed gas for a 40 watt rapid start. A shaped fluorescent lamp was made. The average firing voltage of this lamp was 193 volts. On the other hand, this phosphor
When Ba _0.5 Pb _0.5 TiO ₃ was added and the amount added was varied, the decrease in the discharge starting voltage increased linearly in proportion to the amount added, and the discharge start when the amount added was 2% by weight. The average voltage was 187 volts.

In the seven embodiments described above, a 40 watt rapid start type fluorescent lamp was described, but it goes without saying that the present invention can also be applied to a 20 watt type rapid start type fluorescent lamp.

Furthermore, for the same reason as described in Example 1, the amount of the discharge starting voltage lowering substance added in Examples 2 to 7 was 0.1 to 3% relative to the phosphor.
Optimally, it is expressed as % by weight.

As described above, the present invention makes it possible to lower the discharge starting voltage of a rapid-start type fluorescent lamp having a transparent conductive coating on the inner surface of the tube, and can be used with any gas composition. Even if a rapid-start fluorescent lamp is constructed using a light body, this lamp can be installed in a fixture with a conventional rapid-start fluorescent lamp ballast, even in low-temperature environments. It can be lit reliably.

[Brief explanation of drawings]

FIG. 1 is a graph showing the relationship between the amount added and the reduction in discharge starting voltage in the fluorescent lamp according to the present invention, and FIG. 2 is a graph showing the relationship between the amount added and the luminous flux reduction rate in the fluorescent lamp according to the present invention. be. 1,4: BaTiO ₃ , 2,5: PbTiO ₃ , 3,
6 _{: Ba0.5Pb0.5TiO3 .}

Claims (1)

[Claims] 1. A fluorescent lamp in which a transparent conductive coating is provided on the inner surface of a glass tube and a phosphor coating is provided thereon, in which the phosphor coating is made of barium titanate,
A fluorescent lamp comprising a phosphor to which 0.1 to 3% by weight of at least one substance selected from the group consisting of lead titanate and lead/barium titanate is added to the phosphor.