JPH0678523B2 - Fluorescent lamp - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a fluorescent lamp, and more particularly to an improvement of an anti-fading type high color rendering fluorescent lamp.

(Prior Art) A general fluorescent lamp emits light from a visible wavelength range to a short wavelength range of 400 nm or less including mercury emission lines of 313 nm and 365 nm. It is known that such emission energy of 400 nm or less causes fading of various object colors. For this reason, anti-fading fluorescent lamps that cut off the light emission energy on the short wavelength side are used for lighting such as museums and exhibitions of object colors where color is important.

This anti-fading fluorescent lamp transmits or reflects visible light on the inner surface of the glass tube, and adheres an anti-fading layer that absorbs ultraviolet rays, and further, a phosphor layer that emits light in the visible wavelength range on the anti-fading layer. It has a deposited structure. The fading of the object color is prevented by absorbing the ultraviolet rays emitted from the phosphor layer with the fading prevention layer.

By the way, conventionally, as a fluorescent lamp exhibiting a color rendering AAA type in such a fading-preventing type, one described in JP-A-54-102071 is known.

However, since this fluorescent lamp uses a mixture of four types of phosphors having greatly different chromaticity points as the phosphor layer, chromaticity adjustment is extremely difficult when manufacturing this fluorescent lamp in mass production equipment. Difficult to do. In addition, the manganese-activated zinc silicate phosphor (ZnSiO ₄ : Mn) used in the phosphor layer of this fluorescent lamp has a large deterioration when the fluorescent lamp is turned on for a long time. Has changed, and the luminous flux of the lamp has decreased.

On the other hand, in recent years, the illumination light source in the museum also has fluorescence that brings the light color of the fluorescent lamp closer to that of a light bulb to enhance the illumination effect, depending on the exhibits and contents. For example, lamps with a correlated color temperature of about 5000K are used for Western paintings such as oil paintings and Japanese paintings, while lamps with a correlated color temperature of about 3000K are required for ukiyo-e paintings and hanging scrolls.

However, the latter correlated color temperature of 3000 K cannot be obtained with the fluorescent lamp disclosed in Japanese Patent Laid-Open No. 54-102071.

In addition, other known anti-fading fluorescent lamps can
There is no known one that shows the AAA shape and the color of the light bulb, and there has been a demand from the related parties to develop a high color rendering lamp that is comparable to the light bulb.

(Problems to be Solved by the Invention) The present invention has been made in order to solve the above problems, and achieves the same lighting effect as a light bulb while maintaining the advantages of fluorescent lamps such as long life and high efficiency. It is an object of the present invention to provide an anti-fading fluorescent lamp with high color rendering that exhibits a low color temperature (light bulb color).

[Structure of Invention]

(Means and Actions for Solving Problems) The fluorescent lamp of the present invention includes a glass tube, an anti-fading layer which is attached to the inner surface of the glass tube, transmits or reflects visible light, and absorbs ultraviolet rays, and the fading. In a fluorescent lamp having a phosphor layer which is deposited on the prevention layer and emits light in the visible range, the phosphor layer has the general formula M _5-X X (PO ₄ ) ₃ : Eu _X (where M is 2.5-4.0 gram atom Ba, 0.5-2.0 gram atom Ca and 0.01-1.0 gram atom Mg, X
Is at least one selected from F, Cl and Br, 0.01 <x
≦ 0.25), and a first phosphor comprising a divalent europium-activated alkaline earth metal halophosphate phosphor having an emission peak in the wavelength range of 450 to 500 nm, and 620 to 640 nm Has an emission peak in the wavelength range of
A third phosphor composed of a tin-activated strontium-magnesium phosphate phosphor having a half-width of 50 nm and a manganese-activated magnesium fluorogermanate phosphor having an emission peak in the wavelength range of 650 to 660 nm. And a mixture of a white pigment and a yellow pigment is used as the substance deposited on the anti-fading layer.

Hereinafter, the present invention will be described in more detail.

In the present invention, the first phosphor constituting the phosphor layer, that is, the divalent europium-activated alkaline earth metal halophosphate phosphor has an emission peak in the wavelength range of 450 to 500 nm. This first phosphor has Ba as a main component, and the peak wavelength of light emission can be changed by changing the amount of Ca, and the temperature characteristics and brightness of the phosphor can be changed by changing the amounts of Mg and Eu. Can be improved. Hereinafter, the action of each element of the first phosphor and the reasons for limiting the content will be described.

When Ca is about 1.0 gram atom, the peak wavelength of the emission of the first phosphor is about 500 nm, which is the maximum, but when Ca is less than 0.5 gram atom or exceeds 0.2 gram atom, the y value of the chromaticity of the phosphor becomes sharp. And the specified lamp chromaticity cannot be obtained.

As described above, Mg greatly contributes to the improvement of the temperature characteristics and the brightness, but if it is less than 0.01 gram atom or more than 1.0 gram atom, this effect is not remarkable.

Eu also greatly contributes to the improvement of brightness, but when it is less than 0.01 gram atom, the brightness of the obtained phosphor decreases significantly, while when it exceeds 0.25 gram atom, the price becomes expensive and the brightness is significantly increased. There is no improvement. More preferred Fu
The range of the content is 0.05 <x <0.20.

The above-mentioned first phosphor can be easily manufactured as follows. First, Ba, Ca, Mg, F, Cl, Br, P and Eu
A predetermined amount of each source compound such as oxide, phosphate, carbonate, ammonium salt, etc. is weighed, and then these raw materials are sufficiently pulverized and mixed by, for example, a ball mill. Next, the obtained mixture is placed in an alumina or quartz crucible and fired in the air at a temperature of 800 to 1200 ° C. for 1 to 5 hours. After that, the first phosphor can be easily manufactured by cooling, pulverizing, selecting, washing, filtering, drying and selecting the fired product.

As a result of computer simulation, the first
The color rendering of the fluorescent lamp obtained by mixing tin-activated strontium-magnesium orthophosphate phosphor as the second phosphor and manganese-activated magnesium fluoro-germanate phosphor as the third phosphor with the above phosphor. It has been found that can improve.

Second phosphor, tin-activated strontium orthophosphate
The magnesium phosphor has an emission peak in the wavelength range of 620 to 640 nm and a full width at half maximum of 120 to 150 nm.

The third phosphor, manganese-activated magnesium fluorogermanate, has an emission peak in the wavelength range of 650 to 660 nm, and is particularly effective for improving the color rendering index of red (R ₉ ).

The mixing ratio of these first to third phosphors is preferably 10 to 30% for the first phosphor, 55 to 87% for the second phosphor, and 3 to 15% for the third phosphor. .

Here, when the mixing ratio of the first phosphor is less than 10%, JIS Z9
The color temperature is lower than 2600K of the light bulb color classification of 112-1983,
On the other hand, if it exceeds 30%, the color temperature becomes higher than 3150K, which is not suitable. Similarly, the second phosphor has a similar mixing ratio.
If it is less than 55%, the color temperature becomes high, while if it exceeds 87%, the color temperature becomes low, and both fall outside the above color temperature range.
It is not possible to obtain a fluorescent lamp having a predetermined characteristic. Further, if the compounding ratio of the third phosphor is less than 3%, the effect of improving the color rendering index of red is small and R _{9 of} 80 or more cannot be obtained.
If it exceeds%, not only the lamp price becomes expensive, but also the amount of red component is too large for the whole, and R _{9 of} 80 or more cannot be obtained.

Next, the substance adhered to the anti-fading layer used in the present invention will be described. The conventional substance used in the anti-fading fluorescent lamp was a method using only a white pigment such as titanium oxide as disclosed in Japanese Patent Laid-Open No. 54-102071.

However, when this conventional technique is applied to the lamp of the present invention as it is, the color rendering property is good, but the ultraviolet ray (300 to 400 n
m) was detected in trace amounts. This amount is a value that can be ignored in terms of fading to the object color, but a new substance was required for complete removal, and its study was conducted.

Conventionally, yellow lead, cadmium yellow, etc. have been used as yellow pigments, but lead and its compounds, cadmium and its compounds, etc. have recently been designated as harmful substances,
Since the use thereof is also limited, the present inventors can safely use the TiO ₂ --NiO--S, which is safe in place of these.
By using a yellow pigment having a b ₂ O ₅ -based rutile structure, the above-mentioned object could be achieved.

This is a solid solution in which antimony and nickel atoms are thermally diffused in the crystal lattice of rutile type titanium oxide to develop a yellow color, which has high fastness, excellent heat resistance and chemical resistance,
It can be applied to a fluorescent lamp in exactly the same manner as conventional titanium oxide.

Since this yellow pigment completely absorbs short-wavelength light emission of about 490 nm or less, it cannot be used alone in the lamp of the present invention, but the lamp of the present invention completely removes the desired ultraviolet rays and simultaneously obtains high color rendering. For this purpose, an appropriate amount of the white pigment may be mixed, and the mixing ratio is preferably 1 to 15%.

Here, if the mixing ratio of the yellow pigment is less than 1%, the effect of completely removing ultraviolet rays is small, and a very small amount is detected. On the other hand, if it is 15 (%) or more, the absorption in the blue region becomes large, and not only the light color of the lamp is too yellowish green but also the color rendering property is deteriorated, which is not preferable.

As the white pigment, rutile type one such as TiO ₂ may be used.

According to such a fluorescent lamp of the present invention, it is possible to obtain the same lighting effect as a light bulb while maintaining the advantages of the fluorescent lamp such as long life and high efficiency. Further, it never emits ultraviolet rays that cause fading of the object color. Furthermore, since there are only three types of phosphors that form the phosphor layer, it is very advantageous in terms of manufacturing such as chromaticity adjustment.

(Example) Hereinafter, the Example of this invention is described with reference to drawings.

First, an anti-fading fluorescent lamp according to the present invention will be described with reference to FIG. In FIG. 1, an anti-fading layer 2 made of a mixture of a white pigment 1 and a yellow pigment 2 having a spectral transmittance shown in FIG. 2 is applied to the inner surface of a glass tube 1 having a tube diameter of 32.5 mm. In addition, a phosphor layer 3 is deposited on the fading prevention layer 2. Further, discharge electrodes 4 and 5 are provided at both ends of the glass tube 1.

Next, No. 1 to 3 (first phosphor), N shown in Table 1 below
The fluorescent lamps of Examples 1 to 3 were actually manufactured under the following conditions using o.4 (second phosphor) and No. 5 (third phosphor) phosphors. FIG. 3 shows the spectral distribution of the phosphors Nos. 1 to 5 described above. The numbers in FIG. 3 correspond to the No. of each phosphor. Table 2 below shows some of the manufacturing conditions of the fluorescent lamps of Examples 1 to 3.

Example 1 First, a white pigment (titanium oxide) and a yellow pigment were mixed at a ratio of 95: 5, and the mixed solution was applied to the inner surface of a glass tube at a rate of 0.35 mg / cm ² and then baked at a predetermined temperature. Then, an anti-fading layer was formed. Next, as shown in FIG. 3, the phosphors of Nos. 1, 4 and 5 in Table 1 were mixed in a ratio (shown in Table 2) such that the color temperature was 3000 K and the deviation was ± 0. Was applied on the anti-fading layer to form a phosphor layer. Furthermore,
The discharge electrodes 4 and 5 were formed according to a usual method, and a 40 watt type fluorescent lamp (La) was manufactured as a prototype.

Example 2 First, a white pigment (titanium oxide) and a yellow pigment were mixed at a ratio of 85:15, and the mixed solution was applied to the inner surface of a glass tube at a rate of 0.45 mg / cm ² and then baked at a predetermined temperature. Then, an anti-fading layer was formed. Next, as shown in FIG. 3, the phosphors of Nos. 2, 4 and 5 in Table 1 have a color temperature of 2600 K and a deviation of ± 0.005 uv.
The mixture was mixed in such a ratio as shown in Table 2 (shown in Table 2), and the mixture was coated and deposited on the anti-fading layer to form a phosphor layer.
Hereinafter, in the same manner as in Example 1, a 40 watt type fluorescent lamp (Lb) was prototyped.

Example 3 First, a white pigment (titanium oxide) and a yellow pigment were mixed in a ratio of 99: 1, and the mixed solution was applied to the inner surface of a glass tube at a rate of 0.40 mg / cm ² and then baked at a predetermined temperature. Then, an anti-fading layer was formed. Next, the phosphors of Nos. 3, 4 and 5 in Table 1 were mixed in a ratio (shown in Table 2) such that the color temperature was 3150 K and the deviation was 0.003 uv as shown in FIG. Was applied on the anti-fading layer to form a phosphor layer. Thereafter, in the same manner as in Example 1, a 40-watt type fluorescent lamp (L
c) was prototyped.

Table 2 shows the lamp characteristics of the fluorescent lamps of Examples 1 to 3 and the 40 watt type common type light bulb (Comparative Example, Ld). The standard of JIS Z9112-1983 is also shown in Table 2. The spectral distribution of these lamps is shown in FIG.

As is clear from Table 2, the fluorescent lamps of Examples 1 to 3 have the color rendering AAA according to the color rendering category defined in JIS Z9112-1983.
The shape and light source color classification show numerical values that greatly exceed the color rendering index of each bulb color. In addition, the fluorescent lamps of Examples 1 to 3 have almost the same color rendering index as that of the ordinary light bulb (comparative example), which is the most basic light source, and the front luminous flux and the life are each about 4 times. ing. Further, as is clear from FIG. 5, the ordinary type light bulb (Ld) emits ultraviolet rays that cause fading, whereas the fluorescent lamps (La, Lb, Lc) of Examples 1 to 3 emit ultraviolet rays. Not detected at all.

Since the phosphor layers of the fluorescent lamps of Examples 1 to 3 are a mixture of only three kinds of phosphors, it is also advantageous from the aspect of lamp manufacturing such as chromaticity adjustment.

[Effects of the Invention] According to the present invention as described in detail above, it is possible to obtain the same lighting effect as a light bulb while maintaining long life and high efficiency.
Moreover, it is possible to provide an anti-fading fluorescent lamp which is advantageous in terms of manufacturing.

[Brief description of drawings]

FIG. 1 is a sectional view of a fluorescent lamp according to the present invention, FIG. 2 is a curve diagram showing a relative spectral transmittance of a pigment for an anti-fading layer used in the fluorescent lamp of the present invention, and FIG. 3 is Example 1 of the present invention. 3 to 3 are spectral distribution charts of phosphors used in the fluorescent lamps, FIG. 4 is a chromaticity diagram showing light colors of the fluorescent lamps of Examples 1 to 3 of the invention, and FIG. 5 is Example 1 of the invention. FIG. 4 is a spectral distribution diagram of the fluorescent lamps and the ordinary bulbs of FIG. 1 ... glass tube, 2 ... fading prevention layer, 3 ... phosphor layer,
4, 5 ... Discharge electrodes.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location H01J 61/44 N 7135-5E

Claims (3)

[Claims] 1. A glass tube, which is adhered to the inner surface of the glass tube,
In a fluorescent lamp having a fading prevention layer that transmits or reflects visible light and absorbs ultraviolet rays, and a phosphor layer that is deposited on the fading prevention layer and emits light in the visible range, the phosphor layer has the general formula: M _5-X X (PO ₄ ) ₃ : Eu _X (where M is 2.5 to 4.0 gram atom Ba, 0.5 to 2.0 gram atom Ca and 0.01 to 1.0 gram atom Mg, and X
Is at least one selected from F, Cl and Br, 0.01 <x
≤0.25), and a first phosphor composed of a divalent europium-activated alkaline earth metal halophosphate phosphor having an emission peak in the wavelength range of 450 to 500 nm, and 620 to 640 nm Has an emission peak in the wavelength range of
A second phosphor composed of a tin-activated strontium magnesium phosphate phosphor having a half width of 50 nm and a manganese-activated magnesium fluorogermanate phosphor having an emission peak in the wavelength range of 650 to 660 nm. The fluorescent lamp is characterized in that it is made of a mixture of the above-mentioned phosphors and a mixture of a white pigment and a yellow pigment as a substance to be adhered to the anti-fading layer. 2. The fluorescent lamp according to claim 1, wherein a substance having a rutile structure of TiO ₂ —NiO—Sb ₂ O ₅ type is used as the yellow pigment. 3. The color rendering evaluation index indicates a color rendering AAA type in the color rendering property defined in JIS Z9112-1983, and belongs to the light bulb color in the light source color classification. Fluorescent lamp.