KR100432664B1 - BLUE PHOSPHOR PRODUCED BY ADDING TELBIUM TO BARIUM MAGNESIUM ALUMINATE PHOSPHOR USING Eu AS ACTIVATOR - Google Patents

Abstract

PURPOSE: A blue phosphor is provided to achieve improved energy transfer efficiency and luminance by adding small amount of telbium to barium magnesium aluminate phosphor that uses europium as an activator. CONSTITUTION: A barium magnesium aluminate blue phosphor is expressed as a chemical formula Baa Mgb Alc Oa+b+3c/2:Eud,Tbe, wherein 0.1<=a<=2.4, 0.1<=b<=5, 8<=c<=64, 0.1<=d<=4, and 50ppm<=e<=2000ppm. The blue phosphor has a luminance which is improved by 5 to 15% by adding small amount of telbium to barium magnesium aluminate phosphor that uses europium as an activator.

Description

Blue phosphor

[Industrial Applicable Field]

The present invention relates to a blue phosphor, and more particularly, to an aluminate phosphor used as a blue phosphor of a three-wavelength fluorescent lamp.

BACKGROUND ART [0002]

In general, a fluorescent lamp uses a phosphor that emits visible light by being excited by light of a wavelength of 254 nm generated by the discharge of mercury gas. Conventionally, Ca ₁₀ (PO ₄ ) ₆ (F, Cl) ₂ : Sb, In recent years, trivalent fluorescent lamps have been used in which red, green, and blue phosphors are appropriately mixed. Recently, europium (Eu) has been used as a reverberant as a red color A barium magnesium aluminate fluorescent material in which a yttrium oxide fluorescent material to be used is a magnesium aluminate fluorescent material which uses telbium (Tb) as an activator in green and an europium (Eu) as an activator in blue is used.

Of the above phosphors, BaMgAl ₁₆ O ₂₇ : Eu ²⁺ is first disclosed in Japanese Patent Publication No. 52-22836, but has a low brightness and a disadvantage of singularity in the barium magnesium aluminate material which is a blue phosphor. In order to solve the above disadvantages, US Pat. No. 4,249,108, US Pat. No. 4,733,126, and Japanese Patent Publication No. 61-254689 disclose phosphors which are improved in material composition or added with additives to improve the luminance and lifetime characteristics of phosphors. Japanese Patent No. 5350971 also discloses a phosphor which improves the luminance and lifetime characteristics of the phosphor by appropriately adjusting the particle size and the particle size distribution, but is not sufficient for the effect.

It is another object of the present invention to provide a barium magnesium aluminate blue phosphor which is capable of providing a fluorescent lamp having a high luminance and a long life, (Korean Patent Application No. 94-18087) which can be used as a blue component of a device for converting a red phosphor into a red phosphor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a light emission spectrum showing the luminescence characteristics of phosphors prepared according to Examples and Comparative Examples of the present invention in excitation light of 254 nm. FIG.

FIG. 2 shows emission spectra of phosphors prepared according to the examples and comparative examples of the present invention in the excitation light of 394 nm. FIG.

In order to achieve the above object, the present invention provides a barium magnesium aluminate blue phosphor represented by the following formula (1)

[Chemical Formula 1]

0.1? A? 2.4, 0.1? B? 5, 8? C? 64, 0.1? D? 4, and 50 ppm? E? 2000 ppm in the above formula. More preferably, it is preferable that e is 50 ppm? E? 1500 ppm.

A process for producing a barium magnesium aluminate blue phosphor comprising a step of using a compound containing barium as a matrix, a compound containing magnesium and aluminum oxide, using europium oxide as an activator and using a fluorine compound as a flux , And further, a compound containing telbium is further added. The compound containing telbium is preferably selected from the group consisting of talbium oxide, telbium carbonate, telbium nitrate, and telbium sulfate.

[Example]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe preferred embodiments in order to facilitate understanding of the present invention. However, it should be understood that the following examples are provided for a better understanding of the present invention, and the present invention is not limited to the following examples.

Example 1

The following raw materials were thoroughly mixed using a ball mill or a mortar bowl, filled in an alumina crucible and fired at 1400 ° C for 2 hours.

BaCO ₃ 0.1 mole

MgCO ₃ 0.2 moles

Al ₂ CO ₃ 0.8 mole

0.05 mol of Eu ₂ CO ₃

0.03 mol of AlF ₃

Then, the STD phosphor (standard phosphor) using the conventional technique of BaMgAl ₁₀ O ₁₇ : Eu was manufactured through the processes of ball mill, washing, drying and classification. [Tb] = 50 ppm was added to the mixture aqueous dispersion as a raw material of the STD phosphor by using Tb 1000 ppm standard solution, and the resultant was dried and treated with BaMgAl ₁₀ O ₁₇ : Eu, Tb.

Example 2

A phosphor of BaMgAl ₁₀ O ₁₇ : Eu, Tb was prepared in the same manner as in Example 1, except that [Tb] = 100 ppm was added in Example 1.

Example 3

A phosphor of BaMgAl ₁₀ O ₁₇ : Eu, Tb was prepared in the same manner as in Example 1, except that [Tb] = 500 ppm was added in Example 1.

Example 4

A phosphor of BaMgAl ₁₀ O ₁₇ : Eu, Tb was prepared in the same manner as in Example 1, except that 1500 ppm of [Tb] was added in the above Example 1.

Comparative Example

The phosphor of BaMgAl ₁₀ O ₁₇ : Eu prepared in Example 1 was performed in the same manner as in Example 1, except that Telbium (Tb) was not added in Example 1, and Comparative Example was used.

When the phosphors prepared in Examples 1 to 4 and Comparative Examples were excited with light of 254 nm using MSR7000, the emission spectrum was measured and shown in FIG. Spectra 1, 2, 3, 4, and 5 show phosphors of Comparative Examples 1, 2, 3, and 4, respectively. Except for 2, 3, 4, and 5 show intensities the intensity is increased and the luminance is increased. The results are summarized in Table 1 below.

[Table 1]

Emission characteristics in excitation light of 254 nm

As shown in Table 1, in Examples 2, 3 and 4, the luminance was improved by 5 to 15% according to the addition amount of Tb, as compared with the comparative example.

Further, when the phosphors were excited with light of 394 nm using MSR7000, the emission spectrum was measured and shown in FIG. The spectra 1 ', 2', 3 ', 4', and 5 'represent phosphors of Comparative Examples 1, 2, 3, and 4, The intensity of the spectrum is high and the luminance is increased. The results are summarized in Table 2 below.

[Table 2]

Luminescence characteristics in excitation light of 394 nm

As shown in Table 2, in Examples 1, 2, 3 and 4, the luminance was improved by 8.1 to 16.1% according to the addition amount of Tb, as compared with Comparative Example.

It is possible to provide a blue phosphor for a fluorescent lamp in which the luminance is improved by 5 to 15% by adding a small amount of Tb to a barium magnesium aluminate phosphor which uses Eu as a activator to improve energy transfer efficiency, It has become possible to provide a phosphor of high luminance which can be used in a device (Korean Patent Application No. 94-18087) which converts ultraviolet rays of about 394 nm, which is the application of the present inventor, to RGB visible light with a luminance improvement of 17%. In addition, a small amount of Telbium (Tb) was added to barium magnesium aluminate phosphor which uses the existing europium (Eu) as an activator, and the phosphor with improved brightness was made easy and economical without changing firing conditions or other manufacturing methods .

Claims (3)

A barium magnesium aluminate blue phosphor represented by the following formula (1). Formula 1 0.1? A? 2.4, 0.1? B? 5, 8? C? 64, 0.1? D? 4, and 50 ppm? E? 2000 ppm in the above formula. The blue phosphor according to claim 1, wherein e is 50 ppm &lt; = e &lt; 1500 ppm. (0.1? A? 2.4, 0.1? B? 5, 8? C? 64, 0.1? D? 4) in an aqueous dispersion containing a terebium oxide, a telbium carbonate, a telbium nitrate, And adding the selected telbium compound.