JP2003297290A - Fluorescent lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three band type fluorescent lamp having a light color similar to an incandescent lamp and capable of brightly illuminating color while preventing lowering of luminous flux. <P>SOLUTION: A light-emitting layer of a light-emitting tube is formed with a blue phosphor having a emission peak wavelength of 440-470 nm, a green phosphor having a emission peak wavelength of 505-534 nm and a red phosphor having a emission peak wavelength of 600-615 nm as main components, and a mixing ratio among these phosphors is preset in such a manner that a chromaticity point of the light color falls within a range of an ellipse D that a major axis is 0.0360, a minor axis is 0.0191, and an inclination of the major axis from an x-axis is 57.3° with the chromaticity point C (x0, y0)=(0.4519, 0.4086) in the CIE1931XYZ color system as the center. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a fluorescent lamp,
In particular, it relates to a technique for improving the light emission characteristics of a fluorescent lamp.

[0002]

2. Description of the Related Art A fluorescent lamp has an arc tube that emits visible light to the outside when a voltage is applied. This arc tube has a light emitting layer (phosphor layer) mainly composed of a phosphor on the inner surface, and is composed of a glass tube with electrodes sealed at both ends. Mercury, argon, neon, and A rare gas such as krypton is filled in, and the wavelength radiated from mercury excited in the discharge space of the lamp is 25
The phosphor of the light emitting layer is excited by ultraviolet rays of 3.7 nm, and the visible light emitted from this phosphor is emitted to the outside.

As described above, the light emitting mechanism of the fluorescent lamp is different from that of the incandescent light bulb, and it is economically advantageous in that it has a high luminous efficiency and a long life until the lamp is not normally lit. Instead, it is used in various fields including general home lighting. As such a fluorescent lamp, a combination of a plurality of phosphors having a rare earth element as an emission center has an emission peak wavelength of 440 to 47.
0nm blue region and emission peak wavelength 535-570
nm green region and emission peak wavelength of 600 to 615n
A so-called three-wavelength light emitting type fluorescent lamp has been devised in which the power of light emission is concentrated in three wavelength regions of the red region of m.

The three-wavelength emission type fluorescent lamp has a high luminous efficiency and an average color rendering index showing an average fidelity of color as compared with the conventional one using a phosphor which emits white light alone. It has a high color rendering property of Ra = 80 or more, and various colored lights can be obtained by changing the mixing ratio of each phosphor, so that it is becoming the mainstream of the present fluorescent lamps. In particular, in recent years, in order to produce a calm atmosphere, a three-wavelength band emission type fluorescent lamp in which the mixing ratio of a plurality of phosphors is adjusted so that the emission color is in a low color temperature region has been attracting attention.

[0005]

However, the above-mentioned three-wavelength-range light-emitting fluorescent lamp in the low color temperature region actually has a high average color rendering index, but in reality, it is the entire illuminated space. There is a problem that the colored object looks yellowish and the illuminated object cannot be seen in bright colors.

In particular, a so-called light bulb type fluorescent lamp having a three-wavelength band emission type fluorescent lamp integrated with a lighting circuit and having a similar shape to a light bulb is used as an alternative light source for an incandescent light bulb.
Light colors that have a color temperature that is almost the same as that of incandescent light bulbs are widely used, but conventional lamps of this type increase the ratio of red light emission by the red phosphor to become light colors similar to incandescent light bulbs. It has been designed so that the emission spectrum is completely different from that of an incandescent light bulb, so that there is a problem in that the vividness of the colors seen by the eye is significantly inferior to that of an incandescent light bulb.

[0007] Therefore, although the bulb-type fluorescent lamp has great advantages such as reduced power consumption and long life,
Substitution may be difficult due to the above-mentioned color appearance problem, which greatly hinders the spread of the bulb-type fluorescent lamp. In order to solve such a problem, for example, addition of a deep red light emitting component in addition to the above-mentioned three main light emitting phosphors used in a three-wavelength band emission type fluorescent lamp has been studied. As a phosphor, a manganese-activated fluoromagnesium fluorogermanate phosphor having an emission peak wavelength around 650 nm is well known. However, this phosphor has a problem that the luminous flux is greatly reduced when it is used due to the emission of a long wavelength, and the advantage of high luminous efficiency in the fluorescent lamp is greatly impaired.

The present invention has been made in view of the above problems, and has a light wavelength similar to that of an incandescent light bulb, and is capable of vividly illuminating colors while suppressing a decrease in luminous flux. An object of the present invention is to provide a light emitting type fluorescent lamp.

[0009]

In order to achieve the above object, a fluorescent lamp according to the present invention is a fluorescent lamp including an arc tube having a phosphor layer formed on an inner surface thereof, wherein the phosphor layer emits light. A blue phosphor having a peak wavelength of 440 to 470 nm, a green phosphor having an emission peak wavelength of 505 to 534 nm, and a red phosphor having an emission peak wavelength of 600 to 615 nm as main components, and light at the time of lighting. In the CIE1931XYZ color system, the chromaticity point of color is 0.0360 on the major axis and 0.0191 on the minor axis with the chromaticity point (x, y) = (0.4519, 0.4086) as the center.
It is characterized in that the ratio of the blue phosphor, the green phosphor and the red phosphor is set so as to fall within the range of an ellipse whose major axis is inclined from the x-axis by 57.3 degrees.

The phosphors having the above-mentioned three kinds of emission peak wavelengths are the main components, and the chromaticity of the emission color by them is C
By setting the ratio of the blue phosphor, the green phosphor, and the red phosphor so that it falls within the range of a predetermined ellipse in the IE1931XYZ color system, it has a light color similar to that of an incandescent lamp and has a luminous flux of It is possible to obtain a fluorescent lamp that can make the color vivid and preferably illuminate while suppressing the decrease.

In the phosphor layer, the blue phosphor is 0.5 to 10.0% by weight, and the green phosphor is 28.0.
~ 45.0% by weight, the red phosphor is 50.0-70.
It is desirable that the content be 0% by weight.
By adjusting the amount of each phosphor in the phosphor layer specifically within the above-mentioned range by weight, a light color similar to that of an incandescent lamp can be obtained, and the vividness of color appearance is also guaranteed.

Here, the blue phosphor is a europium-activated barium aluminate strontium magnesium aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) phosphor, and a europium-manganese activated barium aluminate phosphor.
Strontium magnesium ((Ba, Sr) MgA
l ₁₀ O ₁₇ : Eu, Mn) phosphor, europium activated barium halocalcium calcium strontium magnesium ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl
₂ : Eu) phosphor, wherein the green phosphor is manganese-activated cerium / magnesium / zinc aluminate (Ce (Mg, Zn) Al).
₁₁ O ₁₉ : Mn) phosphor, and the red phosphor is preferably europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor.

Further, a lighting circuit for lighting the light emitting tube may be provided together with the light emitting tube, and further, it may be configured as a light bulb type fluorescent lamp. In this way, it is possible to obtain a bulb-shaped fluorescent lamp that has a light color similar to that of an incandescent bulb and has a vivid color appearance similar to that of an incandescent bulb. Can be obtained as an advantage.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. (Structure of Light Bulb Fluorescent Lamp) FIG. 1 (a) is a partially cutaway view showing the structure of the light bulb shaped fluorescent lamp according to the present embodiment, and FIG. 1 (b) shows the arc tube thereof. It is a partially expanded sectional view which shows the laminated structure of an inner wall surface. Also, FIG.
FIG. 2 is a view of the bulb-type fluorescent lamp of FIG. 1 seen from below.
Note that the gloves are omitted in FIG. 2 for convenience.

As shown in FIG. 1A, a light bulb type fluorescent lamp 1 includes an arc tube 2 and a base 3 to which the arc tube 2 is attached.
A cover 4 having a substantially conical shape that covers a portion of the base 3 on the side opposite to the arc tube 2, a lighting circuit 5 housed inside the cover 4, a base 6 attached to the top of the cover 5, and light emission. It consists of a glove 7 covering the tube 2. The arc tube 2 comprises three glass tubes 21, 22, 23 bent in a substantially U shape.
The connecting glass tubes 24, 25 having a smaller diameter than those
(Refer to FIG. 2) to form a discharge path having a predetermined length, and both ends of the discharge path are sealed by stems (not shown), and a rare gas such as neon, argon, or krypton is formed inside. And mercury is enclosed. The filament electrode 8 (FIG. 2) is attached to the stem via a lead wire (not shown).

1 is a partially enlarged sectional view of the glass tube 23 on the inner wall surface of each glass tube 21, 22, 23.
As shown in (b), the protective film 9 and the light emitting layer 10 are formed. The protective film 9 is composed of fine particles of a metal oxide such as aluminum oxide or silicon oxide, and prevents sodium in the components of the glass tube from contacting with mercury in the discharge space on the inner surface of the glass tube and deteriorating by lighting. It serves to prevent the luminous flux from decreasing over time.

The light emitting layer 10 is composed of a mixed phosphor containing three predetermined types of phosphors as main components. Details of the types of these phosphors and the mixing ratio thereof will be described later. The lighting circuit 5 has a well-known configuration including a ballast, a capacitor, and other circuit parts, and is supplied with power from a household power source through a base 6 having a shape substantially the same as the base of an incandescent light bulb, and is not illustrated. Filament electrode 8 of arc tube 2 through the lead wire of
A predetermined electric power is supplied to turn on. This makes it possible to directly connect to the socket of the incandescent light bulb and light it.

The globe 7 is made of a material that transmits visible light and is transparent or has been subjected to a treatment for diffusing light so that the appearance of the fluorescent lamp is similar to that of an incandescent lamp. In addition to the above-mentioned arrangement, it plays a role of reducing unevenness of light emitted from the arc tube 2, particularly in the case of a globe subjected to light diffusion processing. The base 3 also serves as a light shielding plate that prevents light from leaking toward the lighting circuit 5. (Components of Phosphor in Light-Emitting Layer) Next, the types of phosphors contained in the light-emitting layer 10 of the fluorescent lamp in the present embodiment and the mixing ratio thereof will be described. Types of Phosphors Used In the present embodiment, as the phosphors of the light emitting layer 10,
A mixed phosphor mainly composed of a blue phosphor having an emission peak wavelength of 440 to 470 nm, a green phosphor having an emission peak wavelength of 505 to 534 nm, and a red phosphor having an emission peak wavelength of 600 to 615 nm. It is used, and is characterized in that a green phosphor whose emission peak wavelength is slightly shifted to the short wavelength side is used as compared with the conventional phosphor.

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 strontium magnesium aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu, M
n) Phosphor, europium activated barium halophosphate calcium strontium magnesium ((Ba, C
At least one selected from a, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) phosphor may be used.

The emission peak wavelength is 505 to 534n.
The green phosphor in m is cerium / magnesium / zinc aluminate (Ce (Mg, Zn) A) activated by manganese.
A l ₁₁ O ₁₉ : Mn) phosphor may be used. The red phosphor having an emission peak wavelength of 600 to 615 nm includes europium-activated yttrium oxide (Y ₂ O ₃ : E).
u) A phosphor may be used.

In general, the larger the particle size of the phosphor, the brighter the light emission. However, if the particle size exceeds 15 μm, the formed light emitting layer looks granular and the appearance may be deteriorated. . If it is 1 μm or less, sufficient brightness cannot be obtained. Therefore, as for any of the above phosphors, those having an average particle diameter in the range of 1 μm to 15 μm are used, and more preferably those in the range of 2 to 10 μm are used.

These mixed phosphors are combined so that 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 phosphors are not dropped into a glass tube when the lamp is completed. It is mixed with a binding agent or the like to be adhered and adjusted as a phosphor suspension. And
This suspension is applied to the inner surface of a glass tube on which a protective film 9 made of fine particles of metal oxide has been formed in advance, dried and baked to form a light emitting layer 10, and both ends of a discharge path are sealed with a stem. Subsequently, the inside of the glass tube is evacuated, and a rare gas and mercury are sealed therein, so that the arc tube 2 is manufactured.

Mixing Ratio of Each Phosphor The above phosphors must be mixed in such a ratio that the light color of a fluorescent lamp using the same becomes substantially the same as the light color of an incandescent lamp. Therefore, an experiment for obtaining the range of light color similar to that of an incandescent light bulb was conducted as follows.

First, a plurality of subjects were presented with two types of light sources having different color temperatures, and subjective evaluation was made on a scale of 5 to determine whether or not the difference in the color of the light felt uncomfortable. As a result of the experiment, compared to an incandescent light bulb with a color temperature of 2800K, almost no difference in light color is felt, or even if a difference in light color is felt, it is perceived as "no problem" (no discomfort). It was revealed that the range of the color temperature used was 2650K or more and 2960K or less.

The chromaticity coordinates of the incandescent lamp are located on the black body radiation locus, but the chromaticity coordinates of the fluorescent lamp are not necessarily located on the black body radiation locus. The range also needs to be defined as a range away from the blackbody radiation locus. CIE1931XYZ is the range of chromaticity that humans perceive to have little difference in color from a particular color.
It has been clarified by MacAdam that the color system is represented by an ellipse centered on the chromaticity coordinate of the specific color (Visual Sensitivities).
to color difference inda
ylight, J .; Opt. Soc. Am. , 32,
247-274 (1942)).

Therefore, as shown in FIG. 3, the chromaticity coordinate C on the black body radiation locus whose color temperature is 2800 K, which is the same as that of an incandescent lamp.
Chromaticity coordinates A (x1, y1) = (0.4397,0.4050) on a blackbody locus with a color temperature of 2960K centered on (x0, y0) = (0.4519,0.4086)
And an ellipse passing through two points of chromaticity coordinates B (x2, y2) = (0.4636, 0.4114) on the black body radiation locus having a color temperature of 2650K were obtained. The major axis, the minor axis, and the tilt angle of the ellipse from the x axis are based on the coefficient revealed by MacAdam (Specification).
of small chromaticity di
FFersences, J .; Opt. Soc. Am. ，
33, 18-26 (1943)).

As a result, the range of light color similar to that of an incandescent lamp is chromaticity point (x) in the CIE1931XYZ color system.
0, y0) = (0.4519,0.4086) as the center of the ellipse D whose major axis is 0.0360, minor axis is 0.0191, and whose major axis is inclined from the x-axis by 57.3 degrees. It became clear that it was within the range. Therefore, the chromaticity point of the light color is CI
In the E1931XYZ color system, phosphors having the above-mentioned emission peak wavelengths are mixed in appropriate proportions so that they fall within the range of the ellipse D, and an arc tube is manufactured by using the mixed phosphor containing them as a main component. By doing so, it becomes possible to obtain a fluorescent lamp having almost the same light color as an incandescent light bulb.

The main component here is 100% of all phosphors.
When referred to as weight%, it means a range of 70 to 100%. That is, phosphors other than the above may be used within the range of 0 to 30%. As a result of repeated experiments, in order for the light color of the fluorescent lamp to fall within the range of the ellipse D, it is desirable that the ratio of each of the main phosphors in the finished lamp product be in the following range. found. Blue phosphor having an emission peak wavelength of 440 to 470 nm: 0.
5 to 10.0 wt% Green phosphor with emission peak wavelength of 505 to 534 nm: 2
8.0 to 45.0% by weight Red phosphor having emission peak wavelength of 600 to 615 nm: 5
0.0 to 70.0% by weight And, when a fluorescent lamp containing a phosphor of such a component is used, the color looks much more vivid than that of a conventional fluorescent lamp, and it is possible to approach an incandescent light bulb. became. (Experiment 1) Next, an experimental example for showing the above effect will be described.

First, a comparative experiment was carried out between a fluorescent lamp FL (product of the present invention) having the following phosphor components and a conventional fluorescent lamp R1. In each case, the rated output was 13 W.

Main Component of Phosphor of Fluorescent Lamp FL (Product of the Present Invention) Blue Phosphor: Europium Activated Barium Strontium Magnesium Aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) Phosphor Emission Peak Wavelength 455 nm 2 wt% Green phosphor: terbium activated cerium-magnesium-zinc aluminate (Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn) phosphor Emission peak wavelength 517 nm 37 wt% Red phosphor: europium activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor Emission peak wavelength 611 nm 61% by weight

Main Component of Phosphor of Fluorescent Lamp R1 (Conventional Product) Blue Phosphor: Europium Activated Barium Strontium Magnesium Aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) Phosphor Emission Peak Wavelength 455 nm 4 wt%, the green phosphor: cerium terbium-activated lanthanum phosphate (LaPO _4: Ce, Tb) phosphor peak emission wavelength 544 nm 41 wt% red phosphor: europium-activated yttrium oxide (Y ₂ O _3: Eu) Phosphor Emission peak wavelength 611 nm 55% by weight Here, the fluorescent lamps FL1 and R1 are made to have the same total amount of phosphors to be used and to have a chromaticity point of almost the same light color as an incandescent light bulb. .

The spectral spectrum of each lamp is as shown in FIG. In the figure, the horizontal axis represents the emission wavelength (n
m), and the vertical axis represents relative energy (%). Further, the solid line shows the spectrum of the fluorescent lamp FL1, and the broken line shows the spectrum of the fluorescent lamp R1. Due to the difference in the emission spectrum, the vividness of the color of the illuminated object was greatly different as shown in Table 1 below.

[0033]

[Table 1]

In this table, "luminous flux ratio" is a value obtained by measuring an unlit lamp after fabrication in accordance with JIS C 7607-1991, and the luminance of the conventional product R1 is 100%.
Expressed as a percentage. The “average color rendering index Ra” is a value indicating the average value of the index indicating the fidelity of color appearance with respect to a plurality of test colors illuminated with test light, and is obtained in accordance with CIE1974.

The "color gamut area ratio Ga" is an index showing the vividness of the average color appearance, and is defined by JIS Z 87.
26-1990 for reference. It is shown that the larger the Ga value, the more vividly the colors look. As is clear from Table 1, in the fluorescent lamp FL1 of the present invention, the luminous flux and Ra are slightly lower than those of the conventional product R1, but the color gamut area ratio Ga could be significantly increased. That is, it is shown that the fluorescent lamp FL1 can illuminate colors more vividly.

Therefore, the fluorescent lamps FL1 and R1 are actually used.
Then, when a space in which various color objects (desk, chair, magazine, curtain, flower, clothes, etc.) and color charts existing in the living space are present is illuminated and visual evaluation is performed, the fluorescent lamp FL1 of the present invention is obtained. When you illuminate with, the color appearance is more beautiful overall,
Especially, the colors of green and red were vividly and preferably felt.
From these, it is apparent that the color gamut area ratio Ga calculated from the emission spectrum and the actual visual evaluation can make the color vivid by using the fluorescent lamp according to the present embodiment, and as a result, can be preferably viewed. Became. (Experiment 2) Next, in order to confirm that the luminous flux of the fluorescent lamp according to the present embodiment is less reduced as compared with the case where a deep red fluorescent material is added to the conventional fluorescent material, the following procedure is performed. Three types of fluorescent lamps of Example 1, Comparative Example 1, and Comparative Example 2 having different phosphor components were produced and tested. The rated output of each test lamp is 40W.

Component of Phosphor of Example 1 (Product of the Present Invention) Blue Phosphor: Europium Activated Barium Calcium Strontium Halophosphate Magnesium ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) Phosphor Emission peak wavelength 456 nm 4 wt% Green phosphor: Manganese activated cerium / magnesium / zinc aluminate (Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn) phosphor Emission peak wavelength 517 nm 34 wt % Red phosphor: europium activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor Emission peak wavelength 611 nm 60% by weight

Components of Phosphor of Comparative Example 1 (Conventional Phosphor + Deep Red Phosphor) Blue Phosphor: Europium Activated Barium Calcium Strontium Magnesium Halophosphate ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) Phosphor Emission peak wavelength 456 nm 3 wt% Green phosphor: Cerium-terbium activated lanthanum phosphate (LaPO ₄ : Ce, Tb) phosphor Emission peak wavelength 544 nm 29 wt% Red fluorescence Body: Europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor Emission peak wavelength 611 nm 22 wt% Deep red phosphor: Manganese-activated fluoromagnesium germanate (3.5MgO · 0.5MgF ₂ · GeO ₂ : Mn) ) Phosphor Emission peak wavelength 650 nm 46% by weight

Component of Phosphor of Comparative Example 2 (Conventional Product) Blue Phosphor: Europium Activated Barium Calcium Strontium Magnesium Halophosphate ((Ba, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) phosphor emission peak 456 nm 5 wt% green phosphor: cerium terbium-activated lanthanum phosphate (LaPO _4: Ce, Tb) phosphor peak emission wavelength 544 nm 40 wt% red phosphor: europium-activated yttrium oxide ( Y ₂ O ₃ : Eu) Phosphor Emission peak wavelength 611 nm 55% by weight In addition, the total amount of the phosphors used in the emission layers of the three types of fluorescent lamps is the same, and the types and blending ratios of the phosphors other than All the lamps were manufactured with the same specifications.

The following Table 2 shows the above Example 1 and Comparative Examples 1 and 2.
Emission characteristics (light flux (lighting 0 hours), chromaticity point x of light color,
y, correlated color temperature, average color rendering index Ra, color gamut area ratio G
The experimental result of a) is shown.

[0041]

[Table 2]

As is clear from Table 2, Example 1 and Comparative Examples 1 and 2 have almost the same chromaticity point as the light color of the incandescent lamp, and it is felt that the colors are almost the same when the lamp is directly seen. You can However, in Example 1 and Comparative Example 1, the color gamut area ratio Ga is significantly improved as compared with Comparative Example 2. In fact, various colored objects (desks,
When a visual evaluation was performed by illuminating a space in which a chair, a magazine, a curtain, curtains, flowers, clothes, etc.) and a color chart are present, Example 1 is the same as the fluorescent lamp of Comparative Example 1, and the fluorescent lamp of Comparative Example 2 is used. In comparison, the overall color was vivid, and as a result, it was felt to be preferable. In Example 1 according to the present embodiment, although the same increase in Ga as in Comparative Example 1 was observed, the decrease in luminous flux was 18.2% less than that in Comparative Example 1. Therefore, it was proved that the fluorescent lamp of Example 1 according to the invention according to the present embodiment makes the color vivid while suppressing the decrease in luminous flux, and as a result, preferably illuminates. (Experiment 3) Next, a comparative experiment similar to the experiment 2 was performed on the fluorescent lamps of Example 2, Comparative Example 3, and Comparative Example 4.
The rated output of each test lamp is 13W.

Component of Phosphor of Example 2 (Product of the Present Invention) Blue Phosphor: Europium Activated Barium Strontium Magnesium Aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) Phosphor Emission Peak Wavelength 455 nm 3 wt% Green phosphor: manganese-activated cerium-magnesium-zinc aluminate (Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn) phosphor Emission peak wavelength 517 nm 36 wt% Red phosphor: europium-activated yttrium oxide ( Y ₂ O ₃ : Eu) phosphor emission peak wavelength 611 nm 61% by weight

Components of Phosphor of Comparative Example 3 (Conventional Phosphor + Deep Red Phosphor) Blue Phosphor: Europium Activated Barium Strontium Aluminate Magnesium ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) Phosphor Emission peak wavelength 455 nm 2 wt% Green phosphor: Cerium terbium activated lanthanum phosphate (LaPO ₄ : Ce, Tb) Phosphor Emission peak wavelength 544 nm 29 wt% Red phosphor: Europium activated yttrium oxide (Y ₂ O ₃ : Eu) Phosphor Emission peak wavelength 611 nm 23 wt% Deep red phosphor: Manganese activated fluoromagnesium germanate (3.5 MgO · 0.5MgF ₂ · GeO ₂ : Mn) phosphor Emission peak wavelength 650 nm 46 wt%

Component of Phosphor of Comparative Example 4 (Conventional Product) Blue Phosphor: Europium Activated Barium Strontium Magnesium Aluminate ((Ba, Sr) MgAl ₁₀ O ₁₇ : Eu) Phosphor Emission Peak Wavelength 455 nm 4 % By Weight Green Phosphor: Cerium-Terbium Activated Lanthanum Phosphate (LaPO ₄ : Ce, Tb) Phosphor Emission Peak Wavelength 544 nm 41% by Weight Red Phosphor: Europium Activated Yttrium Oxide (Y ₂ O ₃ : Eu) Phosphor Emission peak wavelength 611 nm 55% by weight It is to be noted that the total amount of the phosphors used in the light emitting layers of the three types of fluorescent lamps is the same, and the lamps are manufactured with the same specifications except for the type and mixing ratio of the phosphors. It was

The following Table 3 shows Example 2 and Comparative Examples 3 and 4 above.
Emission characteristics (light flux (lighting 0 hours), chromaticity point x of light color,
y, correlated color temperature, average color rendering index Ra, color gamut area ratio G
The experimental result of a) is shown.

[0047]

[Table 3]

As is clear from Table 3, Example 2,
Comparative Examples 3 and 4 have substantially the same chromaticity point as the light color of the incandescent light bulb, and it can be perceived to have almost the same color when directly looking at the lamp. Similar to Experiment 2, in Example 2 and Comparative Example 3, the color gamut area ratio Ga could be significantly improved as compared with Comparative Example 4. In addition, when we actually illuminate the space where there are various colored objects (desks, chairs, magazines, curtains, flowers, clothes, etc.) and color charts that exist in our living space, we perform visual evaluation.
Similar to the fluorescent lamp of Comparative Example 3, Example 2 had an overall brighter color than the fluorescent lamp of Comparative Example 4, and as a result, it was felt to be preferable.

Then, Example 2 according to the present embodiment is
Despite the same increase in Ga as in Comparative Example 3, the decrease in luminous flux was 18.2% less than that in Comparative Example 3. Therefore, it became clear that, in the fluorescent lamp of Example 2, it was possible to illuminate the color vividly and favorably while suppressing the decrease of the luminous flux. In the above, the experiments were carried out for the cases where the rated output was 40 W and 13 W, but similar results are commonly obtained in fluorescent lamps having other rated outputs. (Modification) The present invention has been described above based on the embodiment, but it goes without saying that the content of the present invention is not limited to the above embodiment. For example, in the above embodiment,
I explained about the bulb type fluorescent lamp with gloves,
It may be a bulbless fluorescent lamp without a globe in which the arc tube is exposed as it is. Further, the arc tube is not limited to one in which a plurality of U-shaped glass tubes are connected, but may be one in which one glass tube is bent or molded into a spiral shape by thermal processing.

From the viewpoint of an alternative light source for the incandescent light bulb currently used at home, it goes without saying that the light bulb type integrated with the lighting circuit and the base as described above is desirable, but the indirect lighting or Fluorescent lamps used for other purposes do not necessarily need to be integrated with a lighting circuit or the like. For example, a so-called compact fluorescent lamp that has a long discharge path length in a compact space by simply connecting a plurality of short arc tubes or bending one arc tube without providing a lighting circuit or the like. Or even,
It may be a straight tube fluorescent lamp or a round fluorescent lamp with the highest diffusion rate.

Of these, the structure of the straight tube fluorescent lamp will be briefly described with reference to FIG. FIG. 5 is a cross-sectional view for schematically showing the structure of the straight tube fluorescent lamp. Both ends of the glass tube 31 are sealed by a stem 32, and a rare gas such as neon, argon, or krypton and mercury are sealed inside. Then, the filament electrode 34 is connected to the inner tip portions of the two lead wires 33 held by each stem 32. Then, the caps 36 having the electrode terminals 35 are attached to both ends of the glass tube 31, and the electrode terminals 35 and the lead wires 33 are connected.

As in the above-mentioned embodiment, the inner surface of the glass tube 31 suppresses contact between sodium and mercury on the inner surface of the glass tube, and aluminum oxide, silicon oxide, or the like is used to prevent a decrease in luminous flux over the lighting time. The protective film 37 is made of fine particles of metal oxide, and a light emitting layer 38 made of a mixed phosphor is formed thereon. The light emitting layer 38 of this straight tube fluorescent lamp is made to have the same fluorescent substance component as that of the fluorescent lamp FL in Experiment 1 described above. These phosphors are bound together so that the water or organic solvent that is a solvent, a binder made of a polymer that is soluble in the solvent, and the light-emitting layer that is a mixed phosphor when the lamp is completed will not fall into the glass tube. It is mixed with an agent and the like to prepare a phosphor suspension. Then, the protective film 37 is previously formed.
Is applied to the inner surface of the glass tube 1 having been formed, dried and baked to form the light emitting layer 38, the stems 32 are sealed at both ends, and then the inside of the glass tube 31 is evacuated to emit noble gas and mercury. After encapsulation, an arc tube is manufactured. Then, the base 36 is attached and the straight tube fluorescent lamp is completed.

Even in the case of a straight tube fluorescent lamp having such a structure, a fluorescent substance having an emission peak wavelength in the above-mentioned range is selected as the fluorescent substance, and these are mixed in a ratio satisfying the above-mentioned condition. The same effects as those described for the bulb-type fluorescent lamp can be obtained.

[0054]

As described above, according to the present invention, while having a light color similar to that of an incandescent light bulb, and suppressing a decrease in luminous flux,
It is possible to provide an excellent fluorescent lamp that can make colors look vivid and make the color of an object feel good.

[Brief description of drawings]

FIG. 1 is a partially cutaway cross-sectional view showing a configuration of a light bulb shaped fluorescent lamp according to an embodiment of the present invention.

FIG. 2 is a bottom view of the bulb-type fluorescent lamp of FIG. 1 when a globe is omitted.

FIG. 3 is a diagram showing a range of chromaticity in chromaticity coordinates for having substantially the same light color as an incandescent light bulb.

FIG. 4 is a diagram showing spectral spectra of a fluorescent lamp according to an embodiment of the present invention and a conventional fluorescent lamp in an experimental example.

FIG. 5 is a cross-sectional view showing the configuration of a straight tube fluorescent lamp as a modified example of the present invention.

[Explanation of symbols]

1 Light bulb type fluorescent lamp 2 arc tube 3 base 4 cover 5 lighting circuit 6,36 mouthpiece 7 gloves 8,34 filament electrode 9,37 protective film 10,38 Light emitting layer 21,22,23,31 glass tube 24,25 glass tubes for connection

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5C039 EB11 EB13                 5C043 AA01 AA03 CC09 CD10 DD28                       EB02 EB04 EC06 EC13 EC14

Claims (5)

[Claims] 1. A fluorescent lamp including an arc tube having a phosphor layer formed on an inner surface thereof, wherein the phosphor layer has an emission peak wavelength of 440 to 470 nm.
And the emission peak wavelength of 505 to 534
green phosphor with an emission peak wavelength of 600 to 6
In the CIE1931XYZ color system, the chromaticity point of the light color at the time of lighting is mainly composed of a red phosphor at 15 nm and the chromaticity point (x, y) = (0.4519, 0.40).
86) with the major axis at 0.0360 and the minor axis at 0.0
191 is characterized in that the ratio of the blue phosphor, the green phosphor and the red phosphor is set so as to fall within the range of an ellipse whose major axis is 57.3 degrees from the x-axis. Fluorescent lamp. 2. The blue phosphor is contained in the phosphor layer.
5 to 10.0% by weight, the green phosphor is 28.0 to 4
The fluorescent lamp according to claim 1, wherein the red phosphor is included in an amount of 5.0% by weight and 50.0 to 70.0% by weight. 3. The europium activated barium strontium magnesium aluminate ((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 halophosphate, calcium, strontium, magnesium ((B
a, Ca, Sr, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu) phosphor, wherein the green phosphor is manganese-activated cerium / magnesium / zinc aluminate (Ce (Mg, Zn) Al ₁₁ O ₁₉ : Mn) phosphor, and the red phosphor is a europium-activated yttrium oxide (Y ₂ O ₃ : Eu) phosphor. Fluorescent lamp. 4. The fluorescent lamp according to claim 1, further comprising a lighting circuit for lighting the arc tube together with the arc tube. 5. The fluorescent lamp according to claim 4, which is configured as a light bulb type fluorescent lamp.