JPS6121503B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a novel phosphor that emits red light when irradiated with electron beams, ultraviolet rays, etc. Recently, energy saving has become an important issue in various fields. Looking at this in the case of fluorescent lamps for lighting, it follows that in order to save energy, the efficiency of the phosphor must be increased. When considering phosphor light emission from such a viewpoint, it is necessary to pay special attention to the following two points. That is, the human eye's sensitivity to brightness differs depending on the color of the emitted light, such that greenish colors feel bright and reddish and blueish colors seem dark.
Therefore, the first thing to do is to be satisfied with the sense of brightness as seen by human senses, that is, with respect to visibility. Second, the color of the illuminated object can be reproduced in a natural state, that is, it has good color rendering properties. By the way, high color rendering and high efficiency are generally difficult to coexist, and in order to achieve high color rendering,
Usually, a large amount of red component, which has poor visibility, is required. Therefore, there has been a strong demand for a red phosphor that exhibits high efficiency and high color rendering properties when used in combination with known green phosphors and blue phosphors. Therefore, the inventor conducted studies on various phosphors based on the above objective, and finally succeeded in providing a new red-emitting phosphor. That is, the phosphor according to the present invention is represented by the composition formula 3BaO.2Y ₂ O ₃ :Eu ³⁺ , and trivalent europium Eu ³⁺ is substituted for a part of yttrium Y as an activator. It is a feature. As shown in FIG. 1, this phosphor has a main emission peak around 614 nm and sub-emission peaks around 624 nm and 595 nm when excited by ultraviolet rays, electron beams, etc. Therefore, the color rendering properties are good,
Moreover, it is advantageous in terms of visibility. In addition, trivalent europium as an activator
Eu ³⁺ is calculated as trivalent and is equivalent to yttrium Y.
Practically speaking, it is preferable that 1 to 16 atomic % of the element be substituted with that part. This phosphor can be used, for example, as a raw material.
Select BaCO ₃ , Y ₂ O ₃ and Eu ₂ O ₃ , mix them in predetermined amounts, thoroughly dry mix them, and heat them in a firing furnace at 1000 to 1400°C under an oxidizing atmosphere, preferably an air atmosphere. It is synthesized by baking at a certain temperature for about 1 to 10 hours. This phosphor can be used alone as a red-emitting phosphor, or can be used in combination with other phosphors. Next, an example will be described together with a conventional example. A fluorescent lamp was manufactured using the red phosphor according to the present invention, and its emission characteristics were compared with those of a conventional fluorescent lamp. The phosphors used in this example are as follows. Blue component Sr ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu ²⁺ Green component (Ce・Tb) MgAl ₁₁ O ₁₉ Red component 3BaO・2Y ₂ O ₃ : Eu ³⁺ Mixture of the above phosphors, butyl acetate, nitrocellulose It was dispersed in a thickened product and applied to fluorescent lamp bulbs. In this case, a binder such as calcium pyrophosphate may be added to increase the binding effect. The mixing ratio of each phosphor was expressed as the emission spectrum intensity ratio of each of these phosphors, as shown in Table 1. Here, the emission spectrum intensity ratio is given to the mixed composition.
It represents the ratio of the intensity of each fluorescence spectrum in the mixed composition when the intensity of each fluorescence spectrum is set to 1 when the same amount of UV is applied to each single phosphor.

[Table] As above, 40W, 32mmφ, Ar filled,
We fabricated a 2.5Torr fluorescent lamp and investigated its fluorescent characteristics. The results are shown in Table 2. In addition, the fluorescent lamp is 4200〓, white (chromaticity point x =
0.37, y=0.38).

【table】 [Brief explanation of the drawing]

FIG. 1 is a characteristic diagram showing the spectral energy distribution of the phosphor according to the present invention.

Claims (1)

[Claims] 1 Compositional formula 3BaO・2Y ₂ O ₃ : Represented by Eu ³⁺ , characterized in that trivalent europium Eu ³⁺ replaces a part of yttrium Y as an activator. phosphor. 2. The phosphor according to claim 1, wherein the substitution amount of trivalent europium Eu ³⁺ is 1 to 16 atomic % relative to yttrium Y.