KR19980067655A - Fluorescent lamp - Google Patents

Abstract

The first and second phosphor coatings of one or more of the phosphors are applied on the inner surface of the fluorescent lamp. The first phosphor coating on the glass bulb side has a long afterglow characteristic and is coated with 0.2 mg per 1 cm < ^{2 &} gt ;, and the second phosphor coating is composed of a halophosphate phosphor or a rare earth phosphor. The phosphor coating having a long afterglow characteristic may include, for example, a europium activated strontium aluminum phosphate phosphor.

Description

Fluorescent lamp

The present invention relates to a fluorescent lamp, and more particularly, to an improvement of a fluorescent lamp that emits afterglow sufficient to identify an object for at least 10 minutes after the lamp is turned on.

A fluorescent lamp for afterglow purposes is generally constructed by forming a phosphor coating on the inner surface of a glass bulb, for example, a halophosphate phosphor or a rare earth phosphor. For example, a straight tube 40-watt fluorescent lamp using a halophosphate phosphor has a luminous intensity of 2700-3100 (lm) and is widely used for public offices, large shops, theaters, and lighting for bathhouses and underground shopping malls.

Especially in areas where a large number of bookstores, theaters and underground shopping malls are gathering, human life protection is the priority, and preparations are needed to safely and quickly evacuate from fire, earthquake and other disasters Do.

Therefore, for those facilities that meet stringent conditions, taking into account the size of the large shops and the space occupied by theaters such as theaters and underground shopping malls and the number of people using these facilities, And installation.

The guiding or emergency lighting is normally configured to illuminate a fluorescent or light bulb for at least 20-30 minutes with an illuminance of at least 1 lx using an ordinary power source and using an internal battery in an emergency (during a power outage). Therefore, when a power failure occurs and the general lighting device is inoperable, minimum illumination at a ground surface of 1 lx or more can be ensured, which allows quick and quick evacuation. However, guide lights or emergency lights are expensive compared to general lighting devices. For example, if the aisle guide light is placed along a low wall surface, while distracted by evacuation, people far from the wall will find it significantly more difficult to recognize the aisle guide light than people near the wall, do. On the other hand, it is difficult to evacuate smoothly and quickly if there is a shortage of power during a power outage caused by a disaster or the like in a general home in which the guide light and the emergency light are not installed. Especially, evacuation of children or persons with disabilities will be more difficult.

Therefore, the present applicant has proposed a fluorescent lamp having a phosphor coating consisting of one or more phosphors on the inner surface of a glass bulb, wherein the phosphor coating has a long afterglow characteristics of at least 0.2 mg per cm ² Lt; / RTI >

According to this proposal, by using the fluorescent lamp as a fluorescent lamp for general illumination purposes, at least 0.05 lx of illumination capable of identifying an object can be obtained even 500 seconds after the fluorescent lamp is turned on. Therefore, Of course, it can function as a guide light for power failure.

However, in general use, the fluorescent lamp has a brightness of only 40% of the brightness of an ordinary fluorescent lamp used for illumination purposes, so that the number of the fluorescent lamps to be installed for general use must be increased , Which increases the financial burden of using such lighters.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fluorescent lamp which can be practically used through a relatively simple structure of illumination and has some improvement in maintaining long afterglow characteristics. In order to achieve the above-described objects, the fluorescent lamp of the present invention is manufactured by applying first and second phosphor coatings composed of one or more kinds of phosphors on a glass bulb, wherein the first phosphor coating on the glass bulb side is a long afterglow Lt; / RTI >

As a modification of the present invention, the application amount of the phosphor having a long afterglow characteristic of the first phosphor coating is set to 0.2 mg per 1 cm ² , the second phosphor coating is formed from the phosphor having a long afterglow characteristic, The coating may be formed from one or more rare earth phosphors.

As another modification of the present invention, an ultraviolet light reflection layer made of alumina or magnesia can be formed between the glass bulb and the first phosphor coating.

As another modification of the present invention, a transparent conductive film may be formed between the glass bulb and the first phosphor coating, and additionally, an ultraviolet light reflection layer may be formed between the conductive film and the first phosphor coating.

As another modification of the present invention, the outer surface of the glass bulb can be coated with a transparent protective layer made of a resin tube.

These and other objects, features, and advantages of the present invention will become apparent from the following description, taken in conjunction with the accompanying drawings, illustrating examples of preferred embodiments of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing main elements of a fluorescent lamp according to Embodiment 1 of the present invention. FIG.

2 is a cross-sectional view showing main elements of Embodiment 2 of the present invention.

3 is a cross-sectional view showing main elements of Embodiment 3 of the present invention.

4 is a cross-sectional view showing main elements of Embodiment 4 of the present invention.

5 is a graph showing the relationship between afterglow illuminance and the elapsed time after lighting in the embodiment of the present invention.

6 is an enlarged view of the roughness scale of FIG. 5;

Description of the Related Art [0002]

1: glass bulb 2: first phosphor coating

3: Second phosphor coating 4: Electrode

5: ultraviolet light reflection layer 6: transparent conductive film

7: Protective layer

A fluorescent lamp shown in Fig. 1 using mercury discharge is described as Embodiment 1 of the present invention. In this figure, chemical compounds used in the above-described phosphors having long afterglow characteristics are represented by the general formula MAl ₂ O ₄ , where M is a light-accumulating phosphor, and at least one selected from the group consisting of calcium, strontium and barium A chemical compound composed of a metal element forms a crystalline mother particle. In addition, europium (Eu) is used as an activator, and elements such as dysprosium (Dy) or neodymium (Nd) are used as a coactivator. The average particle diameter of such a phosphor is set to, for example, 2-12 占 퐉 (depending on the Fischer Subsieve Sizer method (FSSS)).

A second phosphor coating (3) consisting of one or more phosphors is applied on top of the first phosphor coating (2). An application amount in the range of 2-5 mg per 1 cm ² is effective for this second phosphor coating 3 and 3.3 mg is the optimum application amount and this layer is for example halophosphate phosphor (Ca ₁₀ (PO ₄ ) ₆ (SrCaBaMg) ₅ (PO ₄ ) ₃ Cl: Eu or the like) or rare earth phosphor (Y ₂ O ₃ : Eu, LaPO ₄ : Ce / Tb, or (SrCaBaMg) ₅ (PO ₄ ) ₃ Cl: Eu or the like). In forming these phosphor coatings 2 and 3, the layer thickness is relatively uniform by reversing the application direction when forming the second phosphor coating 3, as opposed to the coating direction when forming the first phosphor coating 2 . Finally, the electrodes 4 are disposed at both ends of the glass bulb 1.

According to the present embodiment for the first and second phosphor coatings 2 and 3 formed in layers on the inner surface of the glass bulb 1, at least the second phosphor coating 3 on the discharge path side is of the light- A phosphor such as a rare-earth phosphor used in general fluorescent lamps, and as a result, when the lamp is turned on, a significant increase in brightness can be realized since this phosphor is effectively excited by azeotropic light of, for example, 253.7 nm wavelength have. In addition, the first phosphor coating 2 formed on the glass bulb side is excited by ultraviolet light passing through the second phosphor coating 3 to emit light. On the other hand, when the backlight is turned off, almost all the radiated light is radiated directly from the glass bulb 1 to the outside. Therefore, the light directly radiated from the first phosphor coating 2 to the glass bulb side can be radiated to the outside without being lost, and can be effectively used in emergency lighting or other applications. Particularly, since the application amount of the phosphor having a long afterglow characteristic is set to be at least 0.2 mg per 1 cm ² , the first phosphor coating (2) has a luminance of 0.05 lx which can identify an object for a long time even after the fluorescent lamp is turned on Lt; / RTI > As a result, it is stipulated that the general household lighting system or the fire or building standard law should be equipped with an indicator light or emergency lighting which gives afterglow of brightness to identify objects in order to enable smooth and rapid evacuation in the event of a disaster Such a fluorescent lamp can be applied to a general lighting device in a place.

Another embodiment of the present invention in which a transparent ultraviolet light reflecting layer 5 is formed between the glass bulb 1 and the first phosphor coating 2 is shown in Fig. The ultraviolet light reflection layer 5 is formed from alumina (Al ₂ O ₃ ) or magnesia (MgO) having an average particle diameter of, for example, less than 0.1 μm, preferably 30 to 50 nm.

Although the first and second phosphor coatings 2 and 3 are excited by ultraviolet light having a wavelength of, for example, 253.7 nm generated by the discharge between the electrodes 4, the phosphor located on the discharge path side is effectively excited The phosphors located on the glass bulb farther away from the discharge path tend to be excited with a reduced degree of efficiency. However, according to the present invention, the ultraviolet light passing through the first and second phosphor coatings 2 and 3 is reflected by the ultraviolet light reflection layer 5, Lt; RTI ID = 0.0 > UV < / RTI > As a result, the luminous effect of this and the like is increased.

In addition, for example, by forming the ultraviolet light reflection layer 5 made of alumina, the contact between the glass bulb and mercury is prevented, and the color change due to the reversal phenomenon is reduced or eliminated.

Another embodiment of the present invention in which a transparent conductive film 6 is formed between a glass bulb 1 and a first phosphor coating 2 is shown in Fig. This conductive film 6 is formed, for example, by spraying a liquid containing tin chloride on the inner surface of a heated glass bulb and applying the liquid. This film 6 has a resistance value of, for example, about 1-1000 k OMEGA.

This embodiment can be applied to a lighting apparatus equipped with an ignition circuit device for a quick ignition, and is ideal for use in a large shop, a theater, and a place such as an underground shopping mall.

In particular, if the ultraviolet light reflection layer 5 as shown in Fig. 2 is formed between the glass bulb 1 and the conductive film 6, not only the brightness can be improved, but also the film due to the contact of tin and mercury The change in color due to corrosion of the crystal structure of the fluorescent material 6 can be also reduced or controlled, so that the appearance of the fluorescent lamp can be improved. Another embodiment of the present invention in which the protective layer 7 is formed on the outer surface of the glass bulb 1 is shown in Fig. The protective layer 7 is made of a resin material such as polyethylene terephthalate (PET) having a thickness set to, for example, 100-150 mu m. This protective layer 7 is first prepared in a tubular shape, and after the glass bulb 1 is inserted, the tube is shrunk by heating to 150-200 占 폚 so that the tube is brought into intimate contact with the outer surface of the glass bulb 1 . In particular, when the ultraviolet light absorbing agent such as titanium oxide (TiO ₂ ) is mixed with the protective layer 7, not only the optical resistance value of the protective layer 7 can be improved, It can also be used as a layer. This structure can also be applied to the fluorescent lamps shown in Figs.

According to the present embodiment, the protective layer 7 made of resin is formed on the outer surface of the glass bulb 1, and this protective layer not only prevents the glass bulb 1 from being damaged in an emergency, It is possible to radiate enough light to identify an object, thereby enabling a smooth and quick evacuation. Further, the fluorescent lamp can be separated from the optical device, and can be used for a number of purposes as well as a guide light for evacuation. The present invention can be used as a substitute for flash light.

The present invention is not limited to any of the above-described embodiments, but may be applied to annular fluorescent lamps, compact fluorescent lamps and spherical fluorescent lamps as well as 40-watt fluorescent lamps and other straight tube fluorescent lamps. As a phosphor that has a long afterglow property, europium-neodymium-and yttrium-activated calcium aluminate phosphors: a long afterglow property as an addition to those described in the embodiment referred to above such as _{(CaAl 2 O 4 Eu / Nd} / Y) May be used. Further, in a triple phosphor fluorescent lamp made of three or more kinds of fluorescent materials in the second fluorescent material coating, at least one kind of fluorescent material can be replaced with a fluorescent material having long afterglow characteristics.

Next, test measurement results of the respective embodiments of the fluorescent lamp according to the present invention will be described.

The inventors of the present invention have found that cerium- and terbium-activated lanthanum phosphate phosphors (LaPO ₄ : Ce / Tb --- phosphor A) having a light emission peak at a wavelength of 544 nm and long afterglow characteristics, (SrAl ₂ O ₄ : Eu / Dy-Phosphor B) was first prepared, and then the total luminous flux was measured to obtain the results shown in Table 1 below . The application amount of the phosphor is 4.0 mg / cm < ² > uniform for each of the first and second phosphor coatings.

[Table 1]

First phosphor coating Second phosphor coating Total luminous flux (relative value) A phosphor B phosphor 90 B phosphor A phosphor 100

It can be clearly seen from the table that if the total luminous flux in the case where the phosphor A is combined with the phosphor B by the first phosphor coating with the second phosphor coating is 100, . These results demonstrate that the use of a phosphor having a good luminescent effect on the discharge path side can improve the efficiency as a whole. In a fluorescent lamp using a previous combination in which an ultraviolet light reflection layer made of alumina is formed between the glass bulb and the first phosphor coating, the total luminous flux is increased by about 3%.

When the application amount of the phosphor A is constant at 4 mg / cm ² and the application amount of the phosphor B is changed from 0 to 8.0 mg / cm ² or more, the phosphor A and the phosphor B are combined with the first phosphor coating by the second phosphor coating Table 2 shows the total luminous flux and illuminance measured after 300 seconds after the lamp was turned on in the FL40 fluorescent lamp used. Here, illuminance is measured by placing the light meter 10 mm away from the center of the fluorescent lamp.

[Table 2]

Lamp number Application amount of the first phosphor coating (mg / cm ² ) Total luminous flux (relative value) Afterglow illuminance (lx) One 0 100 0 2 0.1 99 0.03 3 0.2 98 0.05 4 0.5 96 0.09 5 1.0 94 0.13 6 2.0 92 0.17 7 3.9 90 0.21 8 5.7 80 0.25 9 8.0 65 0.32

As can be seen from this table, the total luminous flux decreases as the amount of application of the phosphor B increases, but the afterglow illuminance increases. For example, the illuminance that can identify an object during a power outage was determined to be about 0.05 lx, and the amount of phosphor B required to achieve this intensity is at least 0.2 mg / cm ² . Although a fluorescent lamp having a total luminous flux of at least 50% of the luminous flux of a typical fluorescent lamp can be practically suitably used, the application amount of the fluorescent substance should be limited to 8.0 mg / cm ² from the viewpoint of economic use.

The inventors of the present invention have further found that by applying a europium- and dysprosium-activated strontium aluminum phosphate phosphor (Sr ₄ Al ₁₄ O ₂₅ : Eu / Dy --- phosphor C) having a light emission peak of 490 nm as a first phosphor coating, FL40 (Y ₂ O ₃ : Eu --- phosphor D) having a light emission peak at a wavelength of 622 nm, the phosphor A, and a light emitting phosphor having a wavelength of 453 nm (SrCaBaMg) ₅ (PO ₄ ) ₃ Cl: Eu --- Phosphor E) having a peak of the europium-activated strontium-calcium-barium-magnesium phosphor was prepared. The application amounts of the first and second phosphor coatings were 5.3 and 3.4 mg / cm ^2, respectively.

[Table 3]

Phosphor coating The phosphor used Ratio (wt%) Application amount (mg / cm ² ) The first coating C phosphor ---------- 5.3 Second coating D phosphor 32.2 3.4 A phosphor 23.9 E phosphor 43.9

As a result of measuring the characteristics of each of these fluorescent lamps, the total luminous flux is 2842 lm. The total luminous flux of a prior art fluorescent lamp in which the primary phosphate coating is not provided is 3200 lm. The illuminance for the elapsed time after the lamp is turned on is shown in Fig. 5 and Fig. Fig. 6 is substantially the same as Fig. 5 except that the roughness scale on the vertical axis is enlarged. As can be clearly seen from Figs. 5 and 6, the afterglow roughness is 0.2 lx for almost 500 seconds after the back light is turned on, and the object is sufficiently identified with this class of illuminance, and smooth and rapid evacuation is possible. Further, the fluorescent lamp maintains an illuminance of 0.05 lx or more even after 2 hours have elapsed.

While the features and advantages of the present invention have been described in the foregoing description, the description is only illustrative and modifications may be made to adapt some of them within the scope of the appended claims.

As described above, according to the present invention, in which the first and second phosphor coatings are layered on the inner surface of the glass bulb, at least the second phosphor coating on the discharge path side is a rare earth Such as a phosphor, and as a result this phosphor coating is effectively excited by ultraviolet light, for example, at a wavelength of 253.7 nm when the lamp is turned on, resulting in a noticeably increased brightness.

On the other hand, the first phosphor coating is formed so that the coating amount is 0.2 mg or more per 1 cm < ² > on the glass bulb side, and as a result, the coating is excited by ultraviolet light passing through the second phosphor coating to emit light. When the bulb is lit, all of the emitted light is emitted directly to the outside of the bulb. Thus, the light emitted from the first phosphor coating can be directed outward practically without loss and can be effectively used as emergency guidance lights or night illumination. Particularly, when an ultraviolet light reflection layer is formed between the glass bulb and the first phosphor coating, ultraviolet light, which normally passes through the glass bulb, is reflected back by the reflection layer to excite the phosphor, . If the translucent conductive film is additionally formed between the glass bulb and the first fluorescent coating, the starting characteristics of the fluorescent lamp can be improved.

Lastly, for example, when a protective layer made of resin is formed on the outer surface of the glass bulb, not only breakage of the bulb in an emergency is prevented, but also sufficient light is generated so that the bulb can be identified even in a broken state And the protective layer may be detached from the optical device and used as a substitute for flashing.

Claims (12)

In the fluorescent lamp, first and second phosphor coatings containing at least one kind of fluorescent material are formed on the inner surface of the glass bulb, and the first fluorescent material coating on the glass bulb side is formed of a fluorescent material having long afterglow characteristics Fluorescent light. The fluorescent lamp according to claim 1, wherein the application amount of the phosphor having a long afterglow characteristic of the first phosphor coating is 0.2 mg or more per cm ² . 3. The phosphor according to claim 1 or 2, wherein the first phosphor coating is formed of a chemical compound represented by the general formula MAl ₂ O ₄ , wherein M is a light-accumulating phosphor and is composed of calcium, strontium, and barium An element such as dysprosium (Dy) or neodymium (Nd) is used as a coactivator in addition to the use of europium (Eu) as an activator and a chemical compound composed of at least one metal element selected from the group consisting of Wherein the average particle diameter of the fluorescent material is set to 2-12 占 퐉. The fluorescent lamp according to claim 1, wherein the second phosphor coating is formed of a phosphor having a long afterglow characteristic. The fluorescent lamp of claim 1, wherein the second phosphor coating is formed of one or more rare earth phosphors and the second phosphor coating is applied in an amount of 2 to 5 mg / cm ² . 5. The phosphor according to claim 4 or 5, wherein the second phosphor coating is a halophosphate phosphor (Ca ₁₀ (PO ₄ ) ₆ FCl 2: Sb / Mn) or a rare earth phosphor (Y ₂ O ₃ : Eu, LaPO ₄ : Ce / , (SrCaBaMg) ₅ (PO ₄ ) ₃ Cl: Eu, and the like). The fluorescent lamp according to claim 1, wherein an ultraviolet light reflection layer is formed between the glass bulb and the first phosphor coating. The method according to claim 1, wherein a translucent conductive film is formed between the glass bulb and the first phosphor coating, and the translucent conductive film is formed by spraying a liquid containing tin chloride on the inner surface of the heated glass bulb and applying the liquid And has a resistance value of about 1-1000 k ?. The fluorescent lamp according to claim 8, wherein an ultraviolet light reflection layer is further formed between the conductive film and the first phosphor coating. The fluorescent lamp according to claim 7 or 9, wherein the ultraviolet light reflecting layer is made of alumina or magnesia having an average particle diameter of less than 0.1 μm. The fluorescent lamp according to claim 1, wherein the outer surface of the glass bulb is also covered with a transparent protective layer. 12. The fluorescent lamp according to claim 11, wherein the protective layer comprises a resin tube.