JP2015079640A - Fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent lamp using, as a blue band emission phosphor, only an Eu activated aluminate phosphor, for example only BaMgAlO:Eu, without containing an Eu and Mn-coactivated aluminate phosphor, and also capable of satisfying a color rendering index of a narrow band emission fluorescent lamp and a minimum value of a three wavelength band radiation flux type which are stipulated in JIS Z 9112.SOLUTION: A fluorescent lamp includes: a layer of a manganese activated halophosphate phosphor, as an auxiliary luminescent layer, formed at the outermost part excluding a protective film, in a glass tube; and a three wavelength type phosphor layer in an inner layer, as a main luminescent layer, at the inside of the auxiliary luminescent layer, the three wavelength type phosphor layer containing, as a three wavelength phosphor, a red band emission phosphor of YO:Eu, a green band emission phosphor of LaPO:Ce,Tb, and a blue band emission phosphor a color tone of which is adjusted by only an Eu activated aluminate phosphor, for example only BaMgAlO:Eu, without containing an Eu and Mn-coactivated aluminate phosphor.

Description

  The present invention relates to a fluorescent lamp.

Conventionally, in order to satisfy the color rendering index of the narrow-band light-emitting fluorescent lamp specified in JIS Z 9112 and the minimum value of the three-wavelength radiant flux ratio, the three-wavelength fluorescent lamp is Are aluminate phosphors that co-activate Eu and Mn, such as (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ , and Eu-activated aluminate phosphors such as BaMgAl ₁₀ O ₁₇ : Lamps using a mixture of Eu are in widespread use. In addition, since the three-wavelength fluorescent lamp uses an expensive phosphor, a second layer after forming a halophosphate phosphor layer in the vicinity of the inner wall of the translucent airtight container as a technology for reducing the amount of phosphor used. A phosphor having a two-layer phosphor structure in which a three-wavelength phosphor layer is formed is also employed.

JP 57-180468 A

The present invention uses only an Eu-activated aluminate phosphor, for example, BaMgAl ₁₀ O ₁₇ : Eu, as a blue phosphor that did not satisfy the minimum value of the above three-wavelength display conditions in the structure of one light emitting layer. A lamp capable of satisfying the above characteristics by using the combination of the three-wavelength phosphors used in the second layer of the two-layer coating lamp using the manganese-activated halophosphate phosphor as the first layer. With the goal.

The present invention relates to a fluorescent lamp having a glass tube, a pair of electrodes provided at a tube end of the glass tube, a discharge medium containing mercury and a rare gas sealed in the glass tube, and a base. A manganese-activated halophosphate phosphor layer is formed as an auxiliary light emitting layer on the outermost portion of the glass tube excluding the protective film, and a red light is formed as a three-wavelength phosphor on the inner layer as the main light emitting layer inside the auxiliary light emitting layer. Luminescent phosphor Y ₂ O ₃ : Eu, green phosphors LaPO ₄ : Ce, Tb, blue phosphors do not include aluminate phosphors that co-activate Eu and Mn. A three-wavelength phosphor layer having a color tone adjusted only with an activated aluminate phosphor, for example, BaMgAl ₁₀ O ₁₇ : Eu, is provided.

  According to the present invention, the fluorescent lamp capable of satisfying the simplification of the adjustment of the designated chromaticity of the three-wavelength phosphor, the color rendering index of the luminous flux and the narrow-band light-emitting fluorescent lamp, and the minimum value of the three-wavelength radiant flux ratio type. Can be provided.

An overall view of a fluorescent lamp is shown. FIG. 2 shows a cross-sectional view of the tube end of FIG. FIG. 3 shows a partially enlarged view of FIG. 2. FIG. 6 is a graph showing the mixing rate variation lamp characteristics of (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu.

  Details will be described below with reference to the drawings.

  FIG. 1 shows a structural diagram of a straight tube fluorescent lamp as an external view of the fluorescent lamp 100.

  The glass sealing container 11 occupies most of the fluorescent lamp 100. The glass sealing container 11 is filled with several hundred Pa of inert gas such as rare gas and mercury, and electricity is supplied to the lead wires 16 to the electrodes 112 through the cap pins 3 attached to the caps 2 at both ends. When energized, a discharge occurs between the electrodes 112 at both ends, and a current flows. This discharge excites mercury and emits ultraviolet rays. The glass sealing container 11 has a glass tube 18. In this embodiment, the glass tube 18 has substantially the same tube diameter from the center to the end. The phosphor layer 4 formed on the inner surface of the glass sealing container emits near ultraviolet light or visible light using this ultraviolet light as an excitation source. Reference numeral 19 denotes a protective film.

  FIG. 2 shows a cross-sectional view of a fluorescent lamp having two phosphor layers for the lamp of FIG. FIG. 1 is an enlarged view of the vicinity of the tube end 114 of FIG. 2 and 1 correspond to a state immediately after the exhaust pipe 111 is sealed by welding while keeping the inside of the sealed container at a reduced pressure. As shown in FIGS. 2 and 1, both tube end portions 114 of the glass tube 18 have portions where the tube diameter is smaller than the central portion of the glass tube 18. This is to facilitate attachment of the base 2 at the tube end 114. Reference numeral 113 denotes a portion where the glass tube diameter starts to decrease from the center of the glass tube 18 to the tube end 114 of the glass tube 18. Reference numeral 115 denotes a range from the portion 113 where the glass tube diameter starts to decrease to the tube end portion 114.

  The phosphor layer 4 is formed inside the glass sealing container 11. In the present embodiment, the phosphor layer 4 is formed of a first phosphor layer (auxiliary phosphor layer) 110 and a second phosphor layer (main light emitting layer) 116. Inside the central portion of the glass tube 18, the first phosphor layer (auxiliary phosphor layer) 110 and the second phosphor layer (main light emitting layer) 116 are called in order from the side close to the glass tube 18 toward the inside. I will do it.

As shown in FIG. 1, the first phosphor layer (auxiliary phosphor layer) 110 adjacent to the glass sealing container 11 side is formed from one portion 113 starting to decrease to the other portion 113 starting to decrease. However, it is not formed in the range 115 from the portion 113 where the glass tube diameter starts to decrease from the center of the glass tube 18 to the tube end 114 of the glass tube 18 to the tube end 114. By adopting a configuration in which the first phosphor layer (auxiliary phosphor layer) 110 is not formed in the range 115, the phosphor layer is not peeled off at that location, and the appearance can be avoided. Here, a manganese-activated halophosphate phosphor is used as the phosphor used for the first phosphor layer (auxiliary phosphor layer) 110 adjacent to the glass tube 18 side. On the other hand, as the phosphor used in the phosphor layer formed on the discharge space side (second phosphor layer 116 in the present embodiment), a three-wavelength phosphor is used. The fluorescent lamp 100 is a two-layer fluorescent lamp that uses a manganese-activated halophosphate phosphor as the first phosphor layer 110 and a three-wavelength phosphor 102 as the second phosphor layer. . Further, in Example 1 of Table 1, an average color rendering index of a lamp using only the manganese-activated halophosphate phosphor used as the first layer is shown. Further, in Example 2, in a normal three-wavelength phosphor, (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu are set to 2: 8 as a blue region light emitting phosphor. The average color rendering index of the lamp as a mixing ratio is shown. In Example 3, in the phosphor double-layer structure, a layer having a light emission contribution ratio of 5 to 10% (or a first layer thickness designation) of the first halophosphate phosphor is formed. Shows an average color rendering index when a paint using the same blue phosphor mixture as in Example 2 is applied in an amount of 60 to 90% of the normal coating amount.

  Like this characteristic, in the case of light emission with a single-wavelength phosphor single layer, it is a paint having a characteristic of Ra of 83.3. However, as the phosphor double layer structure, the coating amount of the second layer is usually 60 of one layer. By setting the weight to about 90%, Ra can be raised to 84.9 when used as the second layer having a structure in which the first halo layer is used as auxiliary light emission.

Further, in the lamp of only a three-wavelength phosphor in which the mixing ratio of (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu was changed while keeping the chromaticity of the completed lamp the same. The relationship between the luminous flux and Ra is shown in FIG. It can be seen that by reducing the mixing ratio of the phosphor containing Mn in this way, Ra is reduced but the luminous flux value is increased. Using this characteristic, the mixing ratio of (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu is changed as the specifications of the second layer of the phosphor double-layer structure lamp. However, a lamp with the same chromaticity was created. Table 2 shows the characteristics of each lamp. Thus, when the mixing ratio of the phosphor containing Mn is reduced, Ra slightly decreases, but the luminous flux value is improved. For example, when (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu are set to 0:10 rather than 2: 8, Ra is narrow band light emission defined in JIS Z 9112 The luminous flux value can be improved as compared with a lamp containing a phosphor containing Mn, while satisfying the color rendering index of the fluorescent lamp and the minimum value of the radiant flux ratio in the three wavelengths.

As a result, the phosphors of the three-wavelength type have so far been red-range phosphors Y ₂ O ₃ : Eu, green-range phosphors LaPO ₄ : Ce, Tb, and blue-range phosphors (Ba, Sr, Eu). ) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu mixture were used, but only a BaMgAl ₁₀ O ₁₇ : Eu can be used as a blue region emitting phosphor in a phosphor bilayer lamp . In addition, the phosphor mixture type for creating the same color temperature of the three-wavelength fluorescent lamp is selected from the red region phosphor Y ₂ O ₃ : Eu, the green region phosphor LaPO ₄ : Ce, Tb, and the blue region. Luminescent phosphors (Ba, Sr, Eu) (Mg, Mn) Al ₁₀ O ₁₇ and BaMgAl ₁₀ O ₁₇ : Eu, a total of four types, red region phosphor Y ₂ O ₃ : Eu, green region phosphor LaPO ₄ : Ce, Tb, and blue light emitting phosphor BaMgAl ₁₀ O ₁₇ : Eu can be reduced to three types, and the same chromaticity adjustment can be simplified.

DESCRIPTION OF SYMBOLS 100 Fluorescent lamp 2 Cap 3 Cap pin 4 Phosphor layer 11 Glass sealing container 16 Lead wire 18 Glass tube 19 Protective film 110 First phosphor layer (auxiliary phosphor layer)
112 Electrode 114 Tube end 116 Second phosphor layer (main light emitting layer)

Claims (1)

In a fluorescent lamp having a glass tube, a pair of electrodes provided at a tube end of the glass tube, a discharge medium containing mercury and a rare gas sealed in the glass tube, and a base, protection in the glass tube A manganese-activated halophosphate phosphor layer is formed as an auxiliary light-emitting layer on the outermost portion excluding the film, and a red-light-emitting phosphor as a three-wavelength phosphor in the inner layer as a main light-emitting layer inside the auxiliary light-emitting layer Y ₂ O ₃ : Eu, green light emitting phosphor LaPO ₄ : Ce, Tb, blue light emitting phosphor does not contain an aluminate phosphor that co-activates Eu and Mn, and Eu activated aluminate A fluorescent lamp comprising a three-wavelength phosphor layer whose color tone is adjusted only with a salt phosphor.