JP2002298787A - Fluorescent lamp - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluorescent lamp capable of preferably emitting a red color and capable of restraining deterioration of light flux to a minimum. SOLUTION: This fluorescent lamp is equipped with an arc tube having a light emitting layer comprising a mixed phosphor mainly constituted by a blue phosphor having a light emitting peak wavelength of 440 to 470 nm, a green phosphor having a light emitting peak wavelength of 535 to 570 nm, a first red phosphor having a light emitting peak wavelength of 600 to 620 nm, and a second red phosphor having a light emitting peak wavelength of 620 to 640 nm. An energy ratio of a light emitting peak height of 620 to 640 nm to a light emitting peak height of 600 to 620 nm is 40% or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent lamp.

[0002]

2. Description of the Related Art Generally, a fluorescent lamp has a light-emitting layer mainly composed of a phosphor on an inner surface of a glass tube having electrodes sealed at both ends, and mercury, argon, neon,
A rare gas such as krypton is sealed, and the phosphor in the light emitting layer is excited by mainly 253.7 nm ultraviolet rays emitted from the mercury excited in the discharge space of the lamp, and visible light emitted from the phosphor is externally emitted. It is designed to release.

[0003] As described above, the light emission mechanism of a fluorescent lamp is different from that of an incandescent light bulb.
In the point that the life until the lamp stops lighting normally is long,
Fluorescent lamps are used for various purposes including general lighting.

The above-mentioned fluorescent lamp can obtain various light colors by changing the kind of phosphor in the light emitting layer. For example, a fluorescent lamp using an antimony / manganese-activated halophosphate phosphor that emits white light alone has a wide correlation between daylight, neutral white, warm white, and bulb color by adjusting the composition ratio of the phosphor. Light colors in the color temperature range can be realized and have been widely used.

However, the appearance of the color of an object illuminated by the above-mentioned fluorescent lamp, that is, the color rendering property is significantly inferior to that of an incandescent light bulb, and at present, a combination of a plurality of phosphors having a rare earth element as a luminescent center is used. The so-called light emission power is concentrated in three wavelength regions of a blue region having an emission peak wavelength of 440 to 470 nm, a green region having an emission peak wavelength of 535 to 570 nm, and a red region having an emission peak wavelength of 600 to 620 nm. BACKGROUND ART Three-wavelength emission fluorescent lamps achieve high color rendering with high efficiency and are widely used.

[0006] The three-wavelength band fluorescent lamp is
A variety of shapes have become widespread, and in particular, by taking advantage of the good characteristics that can withstand the high load of the phosphor used in the three-wavelength emission fluorescent lamp, connecting a plurality of arc tubes, The so-called compact fluorescent lamp, which has a long discharge length in a compact space by bending the arc tube, integrates the compact arc tube and the lighting circuit that turns it on, and has almost the same shape as an incandescent lamp Have
In recent years, a bulb-type fluorescent lamp that has a base similar to an incandescent lamp and can be directly attached to an incandescent lamp appliance has become well known in recent years.

[0007]

The above three-wavelength emission fluorescent lamp is a light source that achieves high efficiency and high color rendering.
Looking at the emission spectrum, it can be seen that the emission of red light, especially the wavelength of 62
Since the emission of red to deep red light of 0 nm or more is relatively poor, a special color rendering index R9, which is an index indicating the fidelity of red appearance, is given.
Is low, and it is difficult to illuminate a vividly red-colored object beautifully and to correctly distinguish two similar red colors under the illumination of the lamp. In other words, in the current three-wavelength band fluorescent lamp,
It can be said that it is difficult to illuminate red-based colors preferably.

The above problem is more remarkable in a fluorescent lamp in a low color temperature region having a correlated color temperature of 2,600 K to 3,700 K, which has a relatively high red light emission ratio.

In particular, since a bulb-type fluorescent lamp is used as an alternative light source for an incandescent bulb, light of a bulb color has become widespread. The lamp is designed to increase the ratio of red light emission to have a correlated color temperature of 2600K to 3150K, but the emission spectrum is completely different from that of an incandescent lamp. Therefore, although the shape of the bulb-shaped fluorescent lamp is similar to that of the incandescent lamp, there is a big problem that the red color looks dull compared to the incandescent lamp.

[0010] In order to solve this problem, it has been studied to add a red light-emitting component in addition to the three main lights used in a three-wavelength band fluorescent lamp. A manganese-activated fluoromagnesium germanate fluorophore having a wavelength of around 650 nm is well known. However, since this phosphor emits light of a long wavelength, the luminous flux when used is greatly reduced, which is problematic.

Accordingly, an object of the present invention is to provide a fluorescent lamp capable of illuminating red more preferably and minimizing a decrease in luminous flux in order to solve the conventional problem.

[0012]

To achieve the above object, the fluorescent lamp of the present invention has an emission peak wavelength of 440 to 440.
A blue phosphor at 470 nm and an emission peak wavelength of 53
A mixed phosphor mainly composed of a green phosphor at 5 to 570 nm, a first red phosphor having an emission peak wavelength at 600 to 620 nm, and a second red phosphor having an emission peak wavelength at 620 to 640 nm. Consisting of, and 600-62
620-640 nm relative to the peak height of the emission at 0 nm
Characterized by having an arc tube having a light emitting layer in which the energy ratio of the peak height of light emission is 40% or more.

As a result, a fluorescent lamp which can more preferably illuminate red and minimize the reduction in luminous flux can be obtained.

Further, in the fluorescent lamp of the present invention, the peak height of the light emission at 600 to 620 nm is 62%.
The energy ratio of the peak height of the emission at 0 to 640 nm is
More preferably, it is 50% or more and 200% or less.

Further, in the fluorescent lamp of the present invention, the correlated color temperature of the light color is preferably from 2600 K to 3700 K, and the correlated color temperature is from 2600 K to 3150 K.
More preferably, it is K or less.

In the fluorescent lamp according to the present invention, it is preferable that a lighting circuit for lighting the arc tube is provided together with the arc tube.

Further, in the fluorescent lamp according to the present invention, the blue phosphor is a barium aluminate activated with europium.
Strontium magnesium ((Ba, Sr) MgA
l ₁₀ O ₁₇ : Eu) phosphor, europium / manganese activated barium / strontium / magnesium aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu, Mn) phosphor, europium activated barium / calcium / strontium halophosphate・ Magnesium ((Ba, Ca, S
r, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) phosphor, and the green phosphor is cerium / terbium-activated lanthanum phosphate (LaP).
O ₄ : Ce, Tb) phosphor, terbium-activated cerium / magnesium aluminate (CeMgAl ₁₁ O ₁₉ : Tb)
At least one member selected from the group consisting of phosphors, wherein the first red phosphor is a europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor, and the second red phosphor is a europium-activated yttrium oxide. Active yttrium oxysulfide (Y ₂
O ₂ S: Eu) is preferably a phosphor.

[0018]

Embodiments of the present invention will be described below.

FIG. 1 is a sectional view schematically showing a straight tube fluorescent lamp FL1 as an example of a fluorescent lamp having the effect of the present invention.

In FIG. 1, a glass tube 1 is sealed at both ends by a stem 2 and has a neon argon argon inside.
A rare gas such as krypton and mercury are sealed. A filament electrode 4 is attached to the stem 2 by two lead wires 3 to constitute an arc tube having the effects of the present invention. Then, a base 6 provided with an electrode terminal 5 is adhered to the end of the glass tube 1, and the electrode terminal 5 and the lead wire 3 are attached.
Is connected.

On the inner surface of the glass tube 1, a metal such as aluminum oxide or silicon oxide, which functions to suppress the contact of sodium and mercury on the inner surface of the glass tube and to improve the reduction of the luminous flux over the lighting time. A protective film 7 made of oxide fine particles and a light emitting layer 8 made of a mixed phosphor are formed on the protective film 7.

In the straight tube fluorescent lamp FL1, the light emitting layer 8 has a light emission peak wavelength of 455 nm as a blue phosphor.
Europium activated barium strontium magnesium aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : E
u) 22% by mass of phosphor, 37% by mass of cerium / terbium-activated lanthanum phosphate (LaPO ₄ : Ce, Tb) phosphor having an emission peak wavelength of 544 nm as a green phosphor, and emitting as a first red phosphor 611n peak wavelength
m europium-activated yttrium oxide (Y ₂ O ₃ : E
u) A mixed phosphor obtained by mixing 16 mass% of a phosphor and 25 mass% of a europium-activated yttrium oxysulfide (Y ₂ O ₂ S: Eu) phosphor having an emission peak wavelength of 626 nm as a second red phosphor. It is configured.

These mixed phosphors are combined with water or an organic solvent as a solvent, a binder made of a polymer soluble in the solvent, and a light emitting layer made of the mixed phosphor when the lamp is completed so as not to fall off the glass tube. It is mixed with a binder or the like to be attached and adjusted to a phosphor suspension. Then, this suspension is applied to the inner surface of the glass tube 1 on which the protective film 7 made of metal oxide fine particles has been formed in advance.
The light emitting layer 8 is formed by drying and baking, and the stem 2 is sealed at both ends. Subsequently, the inside of the glass tube is evacuated, and a rare gas and mercury are sealed therein, thereby manufacturing a light emitting tube. Then, the base 6 is attached, and the fluorescent lamp FL1 of the present invention is completed.

FIG. 2 shows the spectrum when the straight tube fluorescent lamp FL1 is turned on. In FIG. 2, the horizontal axis indicates the emission wavelength (nm), and the vertical axis indicates the relative energy (%). As shown in FIG. 2, the addition of the europium-activated yttrium oxysulfide (Y ₂ O ₂ S: Eu) phosphor caused the emission ratio at approximately 625 nm (FIG. 2).
* Part) is increasing.

The light emitting layer 8 is a blue phosphor having a peak emission wavelength of 455 nm, europium-activated barium strontium magnesium aluminate ((B
a, Sr) MgAl ₁₀ O ₁₇ : Eu) phosphor is 25 mass%, and a cerium / terbium-activated lanthanum phosphate (LaPO ₄ :) having a light emission peak wavelength of 544 nm is used as a green phosphor.
It is composed of a mixed phosphor obtained by mixing 41% by mass of Ce, Tb) phosphor and 34% by mass of europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor having an emission peak wavelength of 611 nm as a red phosphor. The current straight tube fluorescent lamp R1 manufactured with the same specifications as the fluorescent lamp FL1 except for the above was manufactured as a conventional product.

The fluorescent lamps FL1 and R1 were prepared so as to have chromaticity points of almost the same light color, but a large difference was observed in the color appearance of the illuminated object due to the difference in emission spectrum. The emission characteristics (luminous flux ratio (lighting 0 hours), chromaticity points x and y of light color, correlated color temperature, average color rendering index Ra, and special color rendering indexes R9 to R15) are shown in comparison with Table 1.

[0027]

[Table 1]

As is clear from Table 1, although the luminous flux of the fluorescent lamp FL1 of the present invention is reduced, the special color rendering index R
9 could be greatly improved.

In addition, the fluorescent lamp FL1 of the present invention and the conventional straight tube fluorescent lamp R1 actually use various colors of objects (desks, chairs, magazines, curtains, flowers,
When luminous evaluation was performed by illuminating the space where clothes and the like existed and the color table was present, the overall appearance of colors was more beautiful when illuminated with the fluorescent lamp FL1 of the present invention, and the red-based colors were particularly vivid. I felt it. Therefore, also in the color rendering index,
In actual luminous evaluation, it became clear that the fluorescent lamp of the present invention was excellent in color rendering properties.

According to a further experiment, the effect of improving the color rendering property is 600 to 620 nm, which is emission in the red region.
It was found that there was a correlation with the ratio between the emission intensity of m and the emission intensity of 620 to 640 nm.

FIG. 3 shows a correlated color temperature of 3000 K, 50 K, which was prepared using a mixed phosphor obtained by mixing the phosphors used at the time of producing the straight tube fluorescent lamp FL1 at various ratios.
600 in fluorescent lamps of light colors of 00K and 6700K
620-64 for peak height of emission at ~ 620 nm
The energy ratio of the peak height of the emission of 0 nm and the increase number ΔR9 of the special color rendering index R9 from the current fluorescent lamp R1.
Shows the relationship.

As is apparent from FIG.
As the emission of nm increases, the special color rendering index R9 increases. More specifically, the energy ratio of the peak height of the emission of 620 to 640 nm to the peak height of the emission of 600 to 620 nm is 40% or more. It has been found that ΔR9 is 20 or more in a fluorescent lamp of a light color having a correlated color temperature which is commonly used, and at this time, the appearance of a red-based color is particularly improved. When the energy ratio is 50% or more, ΔR9
Was 30 or more, which was even better.

As described above, as the energy ratio increases, the appearance of the red-based color is improved vividly and beautifully. However, when the energy ratio exceeds 200%, the luminous flux is greatly reduced. I can't say it.

In a fluorescent lamp having a high color temperature, when the energy ratio is 100% or more, a phenomenon that ΔR9 decreases as the energy ratio increases is observed. This is because red is brightly and beautifully illuminated by an increase in emission of 620 to 640 nm.
When the light emission of m becomes relatively large, it indicates that red is illuminated too vividly and color reproduction is not faithful. However, it is known that, depending on the type of color, such as red system, a rather vivid color reproduction tends to be preferred over a faithful color reproduction. It can be said that the effect of the present invention of illuminating beautifully is not lost.

As described above, the energy ratio of the peak height of light emission at 620 to 640 nm to the peak height of light emission at 600 to 620 nm is 40% or more, preferably 50% or more.
It was found that a fluorescent lamp having the effect of the present invention can be obtained at 0% or less.

It was also found that the effect of improving the appearance of the red-based color by the addition of the light emission of 620 to 640 nm differs depending on the light color of the obtained fluorescent lamp. That is, in a fluorescent lamp in a low color temperature region having a correlated color temperature of 2600K or more and 3700K or less, in which the ratio of red light emission is relatively high, and the value of R9 is less than about 25 in the conventional three-wavelength emission fluorescent lamp, The effect of improving the appearance of red-based color by adding 620 to 640 nm light emission is remarkable,
Among them, the fluorescent lamp in the bulb color region having a correlated color temperature of 2600K or more and 3150K or less, in which the value of R9 was extremely low at less than about 10, was most remarkable.

From the above results, the present invention can be applied to any light color of a fluorescent lamp, but a remarkable effect is particularly obtained in a fluorescent lamp in a low color temperature region having a correlated color temperature of 2600 K to 3700 K. Among them, it was found that the most remarkable effect can be obtained with a fluorescent lamp in a bulb color region having a correlated color temperature of 2600K or more and 3150K or less.

Next, FIG. 1 shows the structure of a straight tube fluorescent lamp, but the type of the fluorescent lamp in the present invention may be a round fluorescent lamp in addition to a straight tube fluorescent lamp, and a plurality of arc tubes may be used. By connecting or bending the arc tube,
A compact fluorescent lamp having a long discharge length in a compact space may be used.

Also, by integrating a compact arc tube and a lighting circuit for lighting the same, having almost the same shape as an incandescent lamp, and having a base similar to an incandescent lamp, it can be directly attached to an incandescent lamp appliance. It can also be applied to compact fluorescent lamps.

Here, the bulb-type fluorescent lamp is a light source that has been widely used as a substitute for an incandescent lamp because of its longer life and higher efficiency than incandescent lamps. Unlike other straight tube fluorescent lamps and round tube fluorescent lamps, the light color in the low color temperature region, particularly the light color in the bulb color region, is used at a high rate. However, for the reasons described above, the appearance of red-based colors in a conventional low color temperature region, in particular, a three-wavelength region fluorescent lamp in a bulb color region, is significantly inferior to incandescent lamps.

Accordingly, in the present invention, the low color temperature region,
In particular, it can be said that it is preferable to apply the fluorescent lamp of the present invention to a bulb-type fluorescent lamp from the viewpoint that the effect is particularly remarkable in the bulb color region.

The structure of the bulb-type fluorescent lamp is substantially the same as that of a straight tube fluorescent lamp or a round tube fluorescent lamp, but will be described with reference to FIGS.

FIG. 4 is a front sectional view in which the light emitting tube portion of the bulb-type fluorescent lamp is enlarged and partly cut away, and FIG. 5 is a bottom sectional view of FIG. In the figure, reference numeral 9 denotes a glass tube formed by connecting three glass tubes 91, 91, 91 bent in a U-shape. The glass tube 9 is sealed at both ends of the discharge path with stems (not shown), and a rare gas such as neon, argon, and krypton and mercury are sealed therein.
Further, a filament electrode 10 is attached to the stem by a lead wire (not shown), thereby forming an arc tube having the effects of the present invention.

On the inner surface of the glass tube 9, a protective film 11 made of fine particles of a metal oxide such as aluminum oxide or silicon oxide, and a light emitting layer 12 made of a mixed phosphor are formed on the protective film 11. . The light-emitting layer 12 is made of the above-mentioned mixed phosphor in which the types and ratios are defined so as to have the effects of the present invention.

The arc tube is connected to a lighting circuit 13 composed of a ballast, a capacitor, and other circuit components through a lead wire connected to the filament electrode 10. The lighting circuit 13 is fixed together with the glass tube 9 by a cover 14 and a light-shielding plate 15 which are usually made of a white light-shielding member. Reference numeral 16 denotes a glove made of a transparent member that transmits visible light or a member that has been subjected to a process for diffusing light.

The base 14 is connected to the cover 14, and the base 17 is electrically connected to the lighting circuit 13. Thus, a bulb-type fluorescent lamp which can be directly used as a socket for an incandescent lamp is obtained.

As described above, an example of the structure of the bulb-type fluorescent lamp has been described, but the structure of the bulb-type fluorescent lamp of the present invention is not limited to the above embodiment. For example, in the above embodiment, the globe 16 is provided, but a structure in which the arc tube is exposed as it is and the globe is not provided may be used. Further, the arc tube may be formed by bending or molding a single glass tube by thermal processing, in addition to the one formed by a plurality of glass tubes.

Next, in order to obtain an arc tube having the effect of the present invention, a blue phosphor having an emission peak wavelength of 440 to 470 nm, a green phosphor having an emission peak wavelength of 535 to 570 nm, and an emission peak Wavelength is 600-620n
m, a first red phosphor having a light emission peak wavelength of 620
It is sufficient to use a mixed phosphor mainly composed of the second red phosphor at 640 nm.

As a blue phosphor having an emission peak wavelength of 440 to 470 nm, europium-activated barium strontium magnesium aluminate ((Ba, S
_{r) MgAl 10 O 17: Eu} ) phosphor, europium-manganese-activated barium aluminate strontium magnesium _{((Ba, Sr) MgAl 10} O 17: Eu, M
n) phosphor, europium-activated barium calcium halophosphate strontium magnesium ((Ba, C
a, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) At least one selected from the group consisting of phosphors may be used.

The peak emission wavelength is 535 to 570 n.
m, a cerium / terbium-activated lanthanum phosphate (LaPO ₄ : Ce, Tb) phosphor;
Terbium-activated cerium / magnesium aluminate (C
eMgAl ₁₁ O ₁₉ : Tb) At least one member selected from the group consisting of phosphors may be used.

The emission peak wavelength is 600 to 620 n.
As the first red phosphor at m, a europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor may be used. Further, as the second red phosphor emission peak wavelength in the 620～640Nm, europium-activated sulfide yttrium _{(Y 2 O 2 S: Eu} ) may be used phosphor.

Then, when the fluorescent lamp is used, 600 to 6
620-640 n for the peak height of the emission at 20 nm
The phosphors having the above-mentioned emission peak wavelengths are mixed at an appropriate ratio so that the energy ratio of the peak height of emission of m is 40% or more, preferably 50% or more and 200% or less. By creating an arc tube using the mixed phosphor described above, a fluorescent lamp having the effects of the present invention can be obtained.

Here, the main component is 100% of all phosphors.
When it is represented by mass%, it means a range of 70 to 100%. That is, a phosphor other than the above may be used in the range of 0 to 30% by mass.

[0054]

Next, the present invention will be described with reference to examples and comparative examples.

Example 1 Europium-activated barium calcium halophosphate strontium magnesium ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : E
u) blue phosphor 27 wt%, a cerium terbium-activated lanthanum phosphate (LaPO _4: Ce, Tb) green phosphor 36 mass%, europium activated yttrium oxide (Y ₂ O _3: Eu) red phosphor Using a mixture of 16% by mass and 21% by mass of europium-activated yttrium oxysulfide (Y ₂ O ₂ S: Eu) red phosphor, the chromaticity point of the light color is x = 0.339, A straight tube 40W fluorescent lamp with y = 0.350 (correlated color temperature 5250K) was prepared. When the spectrum of this fluorescent lamp was measured,
620-64 for peak height of emission at ~ 620 nm
The energy ratio of the peak height of emission at 0 nm is 123%
Met.

Comparative Example 1 Europium-Activated Barium Calcium Strontium Magnesium Halophosphate ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : E
u) 26% by mass of blue phosphor, 35% by mass of cerium / terbium activated lanthanum phosphate (LaPO ₄ : Ce, Tb) green phosphor, and europium activated yttrium oxide (Y ₂ O ₃ : Eu) red phosphor Manganese-activated fluoromagnesium germanate (3.5MgO.
0.5MgF ₂ · GeO ₂ : Mn) Using a mixed phosphor obtained by mixing 16% by mass of a deep red phosphor, the chromaticity point of light color is x.
= 0.339, y = 0.350, a straight tube 40W fluorescent lamp was produced.

Comparative Example 2 Europium-activated barium calcium halophosphate strontium magnesium ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : E
u) 30% by mass of a blue phosphor, 39% by mass of a cerium / terbium-activated lanthanum phosphate (LaPO ₄ : Ce, Tb) green phosphor, and europium-activated yttrium oxide (Y ₂ O ₃ : Eu) red phosphor Is mixed at 31% by mass, and the chromaticity point of light color is x = 0.339, y
A straight tube 40W fluorescent lamp having a capacity of 0.350 was produced.

The total amount of the phosphors used in the light-emitting layers of the above three types of fluorescent lamps was the same, and all the lamps were manufactured with the same specifications except for the types and blending ratios of the phosphors.

As described above, the light emission characteristics (luminous flux, luminous flux ratio (lighting 0 hours), chromaticity points x and y of light color,
Correlated color temperature, average color rendering index Ra, special color rendering index R9
To R15) are shown in Table 2.

[0060]

[Table 2]

As is clear from Table 2, R9 of Example 1 and Comparative Example 1 were able to be greatly improved as compared with Comparative Example 2. In addition, when luminous evaluation was performed by actually illuminating a space in which objects of various colors (desks, chairs, magazines, curtains, flowers, clothes, etc.) and a color table existed in the living space, Example 1 showed that Similar to the fluorescent lamp of Comparative Example 1, the overall color appearance was more beautiful than that of the fluorescent lamp of Comparative Example 2, and the red color was particularly vivid. And
In Example 1, although the same increase in R9 as in Comparative Example 1 was observed, the luminous flux ratio was reduced by 3.5% compared to Comparative Example 1.
Was also less. Therefore, in the fluorescent lamp of Example 1, it was possible to more preferably illuminate red, and it was possible to minimize a decrease in luminous flux.

Example 2 Europium-activated barium / strontium / aluminum aluminate ((Ba, S
r) MgAl ₁₀ O ₁₇ : Eu) 3% by mass of blue phosphor, cerium / terbium activated lanthanum phosphate (LaPO ₄ :
(Ce, Tb) 38% by mass of green phosphor and 31% of europium-activated yttrium oxide (Y ₂ O ₃ : Eu) red phosphor.
Mass%, europium-activated yttrium oxysulfide (Y ₂ O ₂
S: Eu) Using a mixed phosphor in which a red phosphor is mixed at 28% by mass, the chromaticity point of light color is x = 0.443, y = 0.43.
A 413 (correlated color temperature of 2960K) 13 W bulb-shaped fluorescent lamp was produced. When the spectrum of this fluorescent lamp was measured, the energy ratio of the peak height of light emission at 620 to 640 nm to the peak height of light emission at 600 to 620 nm was 85%.

(Comparative Example 3) Europium-activated barium strontium magnesium aluminate ((Ba, S
_{r) MgAl 10 O 17: Eu} ) blue phosphor 4 wt%, a cerium terbium-activated lanthanum phosphate (LaPO _4:
(Ce, Tb) 37% by mass of green phosphor and 40% of europium-activated yttrium oxide (Y ₂ O ₃ : Eu) red phosphor.
Using a mixed phosphor obtained by mixing 19% by mass of a manganese-activated fluoromagnesium germanate fluoromagnesium (3.5MgO.0.5MgF ₂ .GeO ₂ : Mn) deep red phosphor at 19% by mass,
A 13W bulb fluorescent lamp with x = 0.443 and y = 0.411 was prepared.

(Comparative Example 4) Europium-activated barium strontium magnesium aluminate ((Ba, S
r) MgAl ₁₀ O ₁₇ : Eu) 5% by mass of blue phosphor, cerium / terbium activated lanthanum phosphate (LaPO ₄ :
(Ce, Tb) 42% by mass of green phosphor and 53% of europium-activated yttrium oxide (Y ₂ O ₃ : Eu) red phosphor.
A 13 W bulb-shaped fluorescent lamp having a light color chromaticity point of x = 0.443 and y = 0.411 was prepared using the mixed phosphor mixed in a mass%.

The total amount of the phosphors used in the light-emitting layers of the above three types of fluorescent lamps was the same, and all the lamps were manufactured with the same specifications except for the types and blending ratios of the phosphors.

As described above, the light emission characteristics (luminous flux, luminous flux ratio (lighting 0 hours), chromaticity points x and y of light color,
Correlated color temperature, average color rendering index Ra, special color rendering index R9
To R15) are shown in Table 3.

[0067]

[Table 3]

As is clear from Table 3, R9 was significantly improved in Example 2 and Comparative Example 3 as compared with Comparative Example 4. In addition, when luminous evaluation was performed by actually illuminating a space where objects of various colors (desks, chairs, magazines, curtains, flowers, clothes, etc.) and a color table existed in the living space, Example 2 was performed. Similar to the fluorescent lamp of Comparative Example 3, the overall color appearance was more beautiful than that of the fluorescent lamp of Comparative Example 4, and the red color was particularly vivid. And
In Example 2, although the same increase in R9 as in Comparative Example 3 was observed, the luminous flux ratio decreased by 4.2% compared to Comparative Example 3.
Was also less. Therefore, in the fluorescent lamp of Example 2, it was possible to more preferably illuminate red, and it was possible to minimize a decrease in luminous flux.

[0069]

As described above, according to the present invention, it is possible to obtain a fluorescent lamp capable of illuminating red more preferably and minimizing a decrease in luminous flux. Thus, the present invention is of great industrial value.

[Brief description of the drawings]

FIG. 1 is a sectional view of a straight tube fluorescent lamp according to an embodiment of the present invention.

FIG. 2 is a spectrum diagram of a straight tube fluorescent lamp according to an embodiment of the present invention.

FIG. 3 Correlation color temperature 3000K, 5000K, 6700
600 to 620 in the fluorescent lamp of the present invention of K light color
It is a figure which shows the relationship between the energy ratio of the peak height of light emission of 620-640 nm with respect to the peak height of light emission of nm, and the increase number (DELTA) R9 of the special color rendering evaluation number R9 from the existing fluorescent lamp.

FIG. 4 is a front sectional view of a bulb-type fluorescent lamp according to an embodiment of the present invention.

FIG. 5 is a bottom sectional view of the bulb-type fluorescent lamp of one embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass tube 2 Stem 3 Lead wire 4 Filament electrode 5 Electrode terminal 6 Base 7 Protective film 8 Light emitting layer 9 Glass tube 10 Filament electrode 11 Protective film 12 Light emitting layer 13 Lighting circuit 14 Cover 15 Shielding plate 16 Globe 17 Base

Claims (6)

[Claims] 1. A blue phosphor having an emission peak wavelength of 440 to 470 nm, and a blue phosphor having an emission peak wavelength of 535 to 570 nm.
m, a green phosphor having an emission peak wavelength of 600 to 62.
A first red phosphor at 0 nm and an emission peak wavelength of 6
When the energy ratio of the peak height of light emission at 620 to 640 nm to the peak height of light emission at 600 to 620 nm is 40% or more, comprising a mixed phosphor mainly containing the second red phosphor at 20 to 640 nm. A fluorescent lamp comprising an arc tube having a certain light emitting layer. 2. The fluorescent lamp according to claim 1, wherein the energy ratio of the peak height of light emission at 620 to 640 nm to the peak height of light emission at 600 to 620 nm is 50% or more and 200% or less. 3. The correlated color temperature of light color is 2600K or more and 37.
The fluorescent lamp according to claim 1, wherein the fluorescent lamp is at most 00K. 4. A correlated color temperature of light color is 2600K or more and 31.
4. The fluorescent lamp according to claim 3, which has a temperature of 50K or less. 5. The fluorescent lamp according to claim 1, further comprising a lighting circuit for lighting said arc tube together with said arc tube. 6. The blue phosphor is a barium strontium magnesium aluminate activated by europium ((B
a, Sr) MgAl ₁₀ O ₁₇ : Eu) phosphor, europium / manganese-activated barium / strontium / magnesium aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : E)
u, Mn) phosphor, europium-activated barium calcium halophosphate strontium magnesium ((B
a, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) at least one selected from the group consisting of phosphors,
The green phosphor is a cerium / terbium activated lanthanum phosphate (LaPO ₄ : Ce, Tb) phosphor, a terbium activated cerium / magnesium aluminate (CeMgAl ₁₁₎
O ₁₉ : Tb) at least one selected from the group consisting of phosphors, wherein the first red phosphor is a europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor, and the second red phosphor is phosphor europium Katsusan sulfide yttrium _{(Y 2 O 2 S: Eu} ) fluorescent lamp according to any one of claims 1 5 is a phosphor.