JP4266339B2 - Long-wavelength ultraviolet-excited alkaline earth aluminate phosphor and light emitting device using the same - Google Patents

Description

  The present invention relates to a long-wavelength ultraviolet excitation alkaline earth aluminate phosphor exhibiting high-luminance emission by long-wavelength ultraviolet light in the wavelength range of 330 to 390 nm, and a high-luminance light-emitting device using this phosphor in a light-emitting portion.

In recent years, LED lamps using light emitting diodes (LEDs) are becoming widespread. LED, which is a semiconductor element, has a long lifetime and high reliability, and its replacement work is reduced when used as a light source. Therefore, various devices such as a light source for backlight, portable devices, PC peripheral devices, OA devices, etc. Application to a display device has been attempted.
In particular, when LED lamps are applied to various uses, it is more important to obtain white light emission with one LED lamp in addition to a color LED having a light emission peak in each desired visible region from blue to red. It is coming. Therefore, a phosphor that absorbs light emitted from the chip and emits blue (B), green (G), and red (R) light is applied to the surface of the LED chip, or is molded on the surface from which the light emitted from the LED chip is extracted. In addition, white light is extracted from a single LED by incorporating a mixture of phosphor powders that absorb light emitted from the chip into the resin constituting the LED lamp and emit light in the colors B, G, and R, respectively. Has been proposed (see Non-Patent Document 1, etc.). Recently, various display devices have been required to have high color reproducibility (color purity), and color reproducibility (color purity) for LED lamps used as display elements of these various display devices has been increased. Further improvement is desired.

In addition to color LEDs such as blue light emission and green light emission, LED lamps that combine LED chips and phosphors as described above emit long-wavelength ultraviolet light having a wavelength of around 370 nm as a light source for exciting the phosphors. LED chips (for example, LED chips having a GaN compound semiconductor layer as a light emitting layer) are used. For this reason, for LED lamps made of LED chips and wavelength conversion materials such as phosphors that absorb light emitted from the chips and convert them into visible light, they absorb long wavelength ultraviolet rays well and emit visible light efficiently. There is a need for wavelength conversion materials.
By the way, among the phosphors of each color emitting that are excited by long wavelength ultraviolet rays, which is one of the wavelength conversion materials used for this kind of application, as the green emitting phosphor, the divalent europium described in Patent Document 1 ( Eu ²⁺ ) and divalent manganese (Mn ²⁺ ) co-activated barium magnesium aluminate phosphor {3 (Ba, Mg) O.8Al ₂ O ₃ : Eu _0.2 , Mn _0.4 } are known. Such Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphors sensitize with europium (Eu ²⁺ ) and emit green light with high color purity very efficiently. This is because when this phosphor is excited with ultraviolet rays having a wavelength of 180 to 390 nm, Eu ²⁺ efficiently absorbs the ultraviolet rays and transmits energy to Mn ²⁺ to emit visible light. It has often been put to practical use as a fluorescent material for fluorescent lamps, and in recent years, this fluorescent material efficiently absorbs long-wavelength ultraviolet light having a wavelength of around 370 nm, and is therefore being applied to LED lamps and the like.

However, Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor {(3 (Ba, Mg) O.8Al ₂ O ₃ : Eu _0.2 , Mn _0.4 ) for LED lamps described in Patent Document 1 An aluminate phosphor composed of magnesium and barium co-activated with Eu ²⁺ and Mn ²⁺ for a copying machine described in Patent Document 2 (0.7 BaO · MgO · 8Al ₂ O ₃ : 0.05 Eu, 0.2 Mn ), fluorescent lamp Eu ²⁺ and Mn ²⁺ coactivated alkaline earth aluminate phosphor disclosed in Patent Document _{3 (Ba 0.9 Eu 0.1 Mg 1.8} Mn 0.2 Al 16 O 27) or the like of the Eu ²⁺ and Mn ²⁺ Co-activated alkaline earth aluminate phosphors have the disadvantage that when these phosphors are used as a wavelength conversion material in the light emitting part of an LED lamp, the emission luminance is low. Further, these Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphors have a first emission peak in the wavelength range of 430 to 490 nm and a second in the wavelength range of 500 to 540 nm. It emits light having an emission peak, but the intensity of the second emission peak is low, which is insufficient as a green phosphor.

JP 2003-160785 A Japanese Patent Laid-Open No. 56-152883 Japanese Examined Patent Publication No. 52-228336 "Proceedings of the 2001 Annual Meeting of the Illuminating Society of Japan", The Illuminating Institute of Japan, September 2001, page 287

  The present invention has been made in view of the above circumstances, and an alkaline earth aluminate phosphor having high emission luminance when irradiated with long-wavelength ultraviolet light in the wavelength range of 330 to 390 nm, and the phosphor as a wavelength conversion material. An object of the present invention is to provide a light-emitting device with high luminance that uses a light-emitting part.

In order to achieve the above object, the inventor of the present invention relates to Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphors, and oxides of alkaline earth metal elements and divalent metal elements constituting the matrix. As a result of detailed examination of the correlation between the composition and luminous intensity, such as the composition ratio with aluminum oxide, the contents of Eu and Mn in the activator, the matrix composition and the concentration range of Eu and Mn in the activator were specified. In particular, a phosphor having high emission luminance is obtained by excitation with long-wavelength ultraviolet light in the wavelength range of 330 to 390 nm, and this phosphor is used as a light source that emits long-wavelength ultraviolet light in the wavelength range of 330 to 390 nm. When used as a wavelength conversion material of a light emitting device having a light emitting portion made of a wavelength conversion material that is excited by the light source and converts to light having a wavelength different from that of the light source. High luminous device has reached the present invention found that the resulting.

That is, the present invention has the following configuration.
(1) is represented by a compositional formula of _{a (P 1-x Eu x} ) O · (Mg 1-y Mn y) O · bAl 2 O 3, green when irradiated with long-wave ultraviolet light in the wavelength range of 330~390nm An alkaline earth aluminate phosphor for long-wavelength ultraviolet excitation characterized by emitting light. (In the formula, P is Ba, represents at least one alkaline earth metal element in the Sr and Ca, a, b, x and y are 0.8 ≦ a ≦ 1.2,4.0 ≦ respectively It represents a number satisfying b ≦ 6.0, 0.10 ≦ x ≦ 0.35 and 0.15 ≦ y ≦ 0.50, provided that the a value is 1.0 and the b value is 5.0. Except when ).
(2) The alkaline earth aluminate for long wavelength ultraviolet excitation according to the above (1), wherein the a value and the b value are numbers satisfying 0.36 ≦ (1 + a) /b≦0.44 Salt phosphor.
(3) The alkaline earth aluminate phosphor for long wavelength ultraviolet excitation according to (1), wherein the x value is in a range of 0.15 ≦ x ≦ 0.25 .
(4) The alkaline earth aluminate phosphor for long-wavelength ultraviolet excitation according to (1), wherein the y value is in the range of 0.25 ≦ y ≦ 0.45 .

( 5 ) At least a light source that emits long-wavelength ultraviolet light in a wavelength range of 330 to 390 nm, and a wavelength conversion material that absorbs at least a part of light emitted from the light source and emits light having a wavelength different from that of the light source. It is a light-emitting device, Comprising: The said wavelength conversion material contains the alkaline-earth aluminate fluorescent substance for long wavelength ultraviolet excitation in any one of said (1) -(4), The light-emitting device characterized by the above-mentioned.
( 6 ) Any one of the above ( 1 ) to (4), wherein the light source is a light emitting diode having a light emitting chip made of a nitride compound semiconductor layer that emits long wavelength ultraviolet rays in a wavelength range of 330 to 390 nm. the light emitting device according to any.
(7) The light-emitting device according to any one of (1) to (4), wherein the light source is a black light that emits long-wavelength ultraviolet light in a wavelength range of 330 to 390 nm .

Since the alkaline earth aluminate phosphor of the present invention was the construction exhibits light emission with high luminance green in the long wavelength ultraviolet excitation of a wavelength range of 330～390Nm, luminescence, such as an LED lamp phosphor When used in the light emitting portion of the device, a light emitting device with high luminance can be obtained.

The alkaline earth aluminate phosphor for exciting long wavelength ultraviolet light of the present invention (hereinafter also referred to as Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphor of the present invention, or simply the phosphor of the present invention) They can be produced in the same manner as conventional Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphors except that they are prepared by blending phosphor raw materials so as to have a predetermined composition.
That is, the phosphor of the present invention has a stoichiometric composition formula a (P _1−x Eu _x ) O · (Q _1−y Mn _y ) O · bAl ₂ O ₃ ( wherein P is Ba, Sr And at least one alkaline earth metal element in Ca, Q represents at least one divalent metal element of Mg and Zn, and a, b, x, and y are each 0.8 ≦ a ≦ 1.2, 4.0 ≦ b ≦ 6.0, 0.10 ≦ x ≦ 0.35 and 0.15 ≦ y ≦ 0.50 , where a value is 1.0 1) P oxide, or P nitrate, nitrate, sulfate, carbonate, halide, hydroxide, etc. , except for the case where b value is 5.0, and the same applies hereinafter) A compound of P that can be converted to an oxide of P at high temperatures, 2) an oxide of Q, or a nitrate, sulfate, carbonate, halo of Q Q compounds that can be converted to Q oxides at high temperatures such as nitrides and hydroxides, and 3) Al oxides or Al nitrates, sulfates, carbonates, halides, hydroxides, etc. at high temperatures Al compounds that can be converted to Al oxides and 4) Eu oxides, or Eu compounds that can be converted to Eu oxides at high temperatures such as Eu nitrates, sulfates, carbonates, halides, hydroxides, etc. And 5) Mn oxides or mixtures of Mn nitrates, sulfates, carbonates, halides, hydroxides, and other Mn compounds that can be converted to Mn oxides at high temperatures, that is, the above 1) to 5) A phosphor raw material compound composed of at least one compound selected from each group of 5) is packed in a heat-resistant container, and a neutral gas atmosphere such as argon gas or nitrogen gas, or nitrogen gas or monoxide containing a small amount of hydrogen gas. carbon By a method for firing one or more times at 1200 to 1700 ° C. in a reducing atmosphere such as scan, composition formula _{a (P 1-x Eu x} ) O · (Q 1-y Mn y) O · bAl 2 O The alkaline earth aluminate phosphor of the present invention represented by ₃ can be produced. In the present invention, a composition formula _{a (P 1-x Eu x} ) O · (Q 1-y Mn y) O · bAl 2 alkaline earth aluminate phosphor represented by _{O 3} is obtained The phosphor in which the constituent ratio of each metal element contained in the phosphor satisfies the composition formula.

Further, when the raw material compound is fired, a fluorine-containing compound or boron-containing compound may be added to the raw material compound as a flux and fired. In addition, the manufacturing method of the phosphor of the present invention is not limited to the above-described method, and can be manufactured by any conventionally known method as long as the composition is in the stoichiometric range. .
Then the composition formula of _{a (Ba 1-x Eu x} ) O · (Mg 1-y Mn y) O · bAl 2 O 3, Eu 2+ and Mn ²⁺ coactivated barium magnesium aluminate phosphor Taking the body as an example, the results of studying the correlation between the matrix composition of the phosphor and the concentrations of the activators (Eu ²⁺ and Mn ²⁺ ) and the emission luminance are shown. The relative luminance shown below means that each phosphor is excited by ultraviolet rays having a wavelength of 365 nm, and the composition formula described in Patent Document 1 is 3 (Ba, Mg) O.8Al ₂ O ₃ : Eu _0.2 , This is a value expressed as a relative value when the emission luminance of the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors represented by Mn _0.4 is 100.

1 and 2 respectively show Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate with an Eu concentration of 0.20 (x = 0.20) and an Mn concentration of 0.35 (y = 0.35). Taking the phosphor {a (Ba _0.80 Eu _0.20 ) O. (Mg _0.65 Mn _0.35 ) O.bAl ₂ O ₃ } as an example, the number of moles of barium europium oxide {(Ba _0.80 Eu _0.20 ) O} in this phosphor ( The relationship between the number of moles of aluminum oxide (b value) and the relative luminance when excited with ultraviolet light having a wavelength of 365 nm, and barium europium oxide {(Ba _0.80 Eu _0.20 ) O} per mole of aluminum oxide magnesium oxide, manganese _{{(Mg 0.65 Mn 0.35) O} } total moles of {(1 + a) / b } value} and the relationship between the relative luminance when excited at a wavelength 365nm UV illustrate respectively It is a graph. 1 and 2, curves A, B and C are 0.5 mol (a = 0.5), 1 mol (a = 1) and 1.5 mol (a = 1.5) of barium europium oxide, respectively. It is a curve shown about the case of. In FIG. 1, the horizontal axis represents the number of moles of aluminum oxide (b value), the horizontal axis in FIG. 2 represents the {(1 + a) / b} value, and the vertical axis represents the relative luminance.

As can be seen from FIG. 1, the emission luminance of the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor greatly depends on its composition. When the number of moles (a value) of barium and europium oxide is constant, the light emission luminance becomes maximum when the barium oxide is about 4 to 6 moles (b = 4 to 6), and it becomes smaller even if the b value is larger than that. Even in this case, the light emission luminance decreases rapidly. In addition, when the number of moles of aluminum oxide (b value) is constant, the emission luminance is maximum when 1 mole (a = 1) of barium oxide and europium, and decreases even when the a value is larger than that. However, the light emission luminance decreases rapidly. In particular, the emission luminance was highest when barium and europium oxide were 1 mol (a = 1) and aluminum oxide was 5 mol (b = 5) (point E in FIG. 1).

Further, as can be seen from FIG. 2, the emission luminance of the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor is 1 (a = 1) in terms of the number of moles of barium and europium oxide, and is 1 mole of aluminum oxide. The total number of moles of barium europium oxide {(Ba _0.80 Eu _0.20 ) O} and magnesium oxide manganese {(Mg _0.65 Mn _0.35 ) O} is 0.4 {(1 + a) /b=0.4, that is, FIG. The maximum is obtained at the point E} on the curve B, and the luminance is lowered regardless of whether the {(1 + a) / b} value is larger or smaller. In addition, the emission luminance is high when the number of moles of barium / europium oxide is 1 (a = 1), and the emission luminance decreases even if the a value is larger or smaller.
On the other hand, in barium magnesium aluminate, the number of moles of barium oxide is 1 (a = 1), and the total number of moles of barium oxide (BaO) and magnesium oxide (MgO) per mole of aluminum oxide is 0.4 {(1 + a). /B=0.4}, that is, when the number of moles of barium oxide is 1 (a = 1) and the number of moles of aluminum oxide is 5 (b = 5), the crystallographically stable single-phase alumina Produces barium magnesium acid. Therefore, in the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor, the number of moles of barium oxide and europium is 1 (a = 1), and barium oxide, europium and magnesium oxide. When the total number of moles of manganese is 0.4 {(1 + a) /b=0.4}, that is, the number of moles of barium and europium is 1 mole (a = 1) and the number of moles of aluminum oxide is 5 (b = In the case of 5), it is considered that since the crystallographically stable single-phase Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor was obtained, the emission luminance was increased.

The phosphor proposed in Patent Document 1 corresponds to a {(1 + a) / b} value of 0.45 in the above composition formula, and the phosphor proposed in Patent Document 2 has the above composition. The number of moles of barium europium oxide is 0.625 (a = 0.625), the number of moles of aluminum oxide is 6.67 (b = 6.67), and the {(1 + a) / b} value is 0.244. In the phosphor composition proposed in Patent Document 3, the number of moles of barium and europium oxide is 0.5 (a = 0.5) and the number of moles of aluminum oxide is 4 (b = 4). ), The {(1 + a) / b} value is 0.375, which corresponds to the point D on FIGS. Comparing the emission luminance of the phosphors in FIGS. 1 and 2, the number of moles of barium and europium is 1 (a = 1), the number of moles of aluminum oxide is 5 (b = 5), and {(1 + a) / B} value is considerably inferior to the phosphor of the present invention having a 0.4 value (point E on FIGS. 1 and 2).
This is because, in the case of the Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphors proposed in each of the above-mentioned patent documents, the composition of the base alkaline earth aluminate is crystallography. This is because the alkaline earth aluminate containing crystallographic impurities is generated because it deviates from the composition of the alkaline earth aluminate that produces a stable single phase. In particular, the alkaline earth aluminate (barium magnesium aluminate) whose composition formula has been expressed as 3 (Ba, Mg) O.8Al ₂ O ₃ or BaMg ₂ Al ₁₆ O _{27 from the} past, such as Patent Document 1, composition formula means a _{BaO · 2MgO · 8Al 2 O 3} , a phosphor different from the composition crystallographically impure alkaline earth aluminate of the present invention (barium magnesium aluminate).

  Therefore, in order to obtain excellent emission characteristics under excitation by long-wavelength ultraviolet light as a phosphor activated with alkaline earth aluminate as a base and europium and manganese, it is crystallographically stable and has few impurity phases. It is important to have a single phase, and the phosphor composition has a {(1 + a) / b} value of 0.4, that is, the number of moles of barium and europium is 1 (a = 1), and the number of moles of aluminum oxide. It is important to make the matrix composition as close as possible to 5 (b = 5).

In FIGS. 1 and 2, Eu ²⁺ and Mn ²⁺ whose composition formula is represented by a (Ba _1−x Eu _x ) O · (Mg _1−y M n _y ) O · bAl ₂ O ₃ Among the active barium magnesium aluminate phosphors, Eu concentration is 0.20 (x = 0.20) and Mn concentration is 0.35 (y = 0.35) {a (Ba _0.80 Eu _0.20 ) O. ( Mg _0.65 Mn _0.35 ) O · bAl ₂ O ₃ }, with the number of moles of barium and europium (a value) as a parameter, the number of moles of aluminum oxide (b value) and the relative luminance when excited by 365 nm ultraviolet light The relationship and the relationship between the total number of moles of barium / europium oxide and magnesium oxide / manganese {(1 + a) / b value} relative to 1 mole of aluminum oxide and the relative emission luminance when excited with ultraviolet light having a wavelength of 365 nm are illustrated. ,wavelength The correlation between the relative emission luminance and the b value when excited with 65 nm ultraviolet light, and the correlation between the relative emission luminance and the {(1 + a) / b} value are Eu concentration (x value) and Mn concentration (y value). It was confirmed that the correlation was almost the same as in FIG.

FIG. 3 shows that the Eu concentration is 0.2 mol (x = 0.2), the number of moles of barium europium oxide is 1 (a = 1), and the number of moles of aluminum oxide is 5 (b = 5). ²⁺ and Mn ²⁺ coactivated alkaline earth barium magnesium aluminate phosphor of _{{(Ba 0.80 Eu 0.20) O} · (Mg 1-y Mn y) O · 5Al 2 O 3} as an example, the phosphor It is the graph which showed the relationship between Mn density | concentration (y value) and the luminescent brightness | luminance (relative value) when excited by 365-nm ultraviolet rays. The horizontal axis represents the number of moles of Mn (y value), and the vertical axis represents the relative luminance.
As can be seen from FIG. 3, the emission brightness of the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor is 0.15 to 0.5 mol of Mn concentration (y = 0.15 to 0.5). And higher, especially at 0.25 to 0.45 mol (y = 0.25 to 0.45), and the emission brightness even when the Mn concentration is higher than 0.5 mol or lower than 0.15 mol Will decline. This is because when the Mn concentration is low, the luminance is low because the number of emission centers is small, and conversely, when the Mn concentration is too high, the luminance is reduced due to concentration quenching.

These Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors have a first emission peak in the wavelength region of 445 to 455 nm when irradiated with long-wave ultraviolet light in the wavelength region of 330 to 390 nm, It emits light having a second emission peak in the wavelength range of 510 to 520 nm. In these phosphors, when the Mn concentration is high, the energy transmitted from Eu to Mn can be easily converted into visible light, so that the intensity of the second emission peak between wavelengths 510 to 520 nm increases rapidly.
In FIG. 3, Eu ²⁺ and Mn ²⁺ co-activated aluminate whose composition formula is represented by a (Ba _1−x Eu _x ) O · (Mg _1−y M n _y ) O · bAl ₂ O ₃ Among barium magnesium phosphors, the Eu concentration is 0.20 (x = 0.20), and the Mn concentration (y value) in the barium magnesium aluminate phosphor having a composition of a and b values of 1 and 5, respectively. The relationship with the emission luminance when irradiated with long wavelength ultraviolet rays in the wavelength range of 365 nm was exemplified, but this correlation was substantially the same even when the europium concentration (x value), a value, and b value changed.

FIG. 4 shows Eu ²⁺ in which the Mn concentration is 0.35 mol (y = 0.35), the number of moles of barium europium oxide is 1 (a = 1), and the number of moles of aluminum oxide is 5 (b = 5). And an Mn ²⁺ co-activated barium magnesium aluminate phosphor {(Ba _1-x Eu _x ) O · (Mg _0.65 Mn _0.35 ) O · 5Al ₂ O ₃ } as an example, the Eu concentration of this phosphor and 365 nm It is the graph which showed the relationship of the luminescence brightness (relative value) when excited with ultraviolet rays. The horizontal axis is Eu concentration (x value), and the vertical axis is relative luminance.
As can be seen from FIG. 4, the emission intensity of the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor is 0.1 to 0.35 mol Eu (x = 0.1 to 0.35). Higher, especially at 0.15 to 0.25 mol (x = 0.15 to 0.25), even if the Eu concentration is higher than 0.35 mol or lower than 0.1 mol Will decline. This is because if the Eu concentration is low, the number of points that absorb and transmit energy is small, so that the luminance is low. Conversely, if the Eu concentration is too high, the luminance is reduced due to concentration quenching.

Regarding the activator concentration of these Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors, the ratio of the number of moles of Mn to the number of moles of Eu (y / x) is kept constant, and the concentration of activator (Eu If the total of Mn and Mn is increased, the intensity of the second emission peak appearing in the wavelength range of 510 to 520 nm is relatively high. This means that Eu exists as a site that absorbs and transmits energy rather than as a blue light emitting site, and the ratio of the number of moles of Mn to the number of moles of Eu as an activator (y / x) In the Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor, it is preferable to make manganese and europium so high that concentration quenching does not occur.

FIG. 4 shows Eu ²⁺ and Mn ²⁺ co-activated aluminate whose composition formula is represented by a (Ba _1−x Eu _x ) O · (Mg _1−y M n _y ) O · bAl ₂ O ₃ Among barium magnesium phosphors, Eu concentration (x value) in a barium magnesium aluminate phosphor having a composition in which the Mn concentration is 0.35 (y = 0.35) and the a value and the b value are 1 and 5, respectively. The relationship with the emission luminance when irradiated with long wavelength ultraviolet rays in the wavelength range of 365 nm was exemplified, but this correlation was almost the same even when the manganese concentration (y), a value, and b value were changed.
Further, the correlation between the a value, the b value, the {(1 + a) / b} value, the x value and the y value, and the relative luminance indicates that P is an alkaline earth metal element other than Ba, or an alkaline earth metal containing Ba. Even if it is an element, it has been confirmed that even if Q is Zn or Mg and Zn, the tendency is almost the same.

From the above results, the phosphor of the present invention, in terms of light emission luminance under excitation with ultraviolet rays having a wavelength of _{365nm, {(Q 1-y} Mn y) O} for _{{(P 1-x Eu x} ) O} in the range molar ratio a is 0.8 to 1.2 of (0.8 ≦ a ≦ 1.2), the molar ratio b of aluminum oxide to _{{(Q 1-y Mn y} ) O} is 4.0 ˜6.0 (4.0 ≦ b ≦ 6.0), particularly 4.5 to 5.5 (4.5 ≦ b ≦ 5.5). Even in the composition range, the total number of moles (a + 1) of {(P _1−x Eu _x ) O} and {(Q _1−y M n _y ) O} with respect to the number of moles (b value) of aluminum oxide. ) Ratio {(a + 1) / b} is more preferably in the range of 0.36 to 0.44 (0.36 ≦ (a + 1) /b≦0.44) in terms of light emission luminance. In addition to the matrix composition, the molar ratio (x) of Eu and the molar ratio (y) of Mn are in the range of 0.10 to 0.35 (0.10 ≦ x ≦ 0.35) and 0.15 to 0, respectively. .50 (0.35 ≦ y ≦ 0.50), and in particular, the x and y values are in the range of 0.15 to 0.25 (0.15 ≦ x ≦ 0.25) and A range of 0.25 to 0.45 (0.25 ≦ y ≦ 0.45 ) is more preferable in terms of light emission luminance.
The Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphor of the present invention having a composition included in the numerical values of the a value, b value, x value and y value is approximately 330 to 390 nm. When excited with ultraviolet rays in the wavelength band, it emits high-brightness blue-green to green light as in the case of excitation with ultraviolet rays with a wavelength of 365 nm. Therefore, the phosphor of the present invention is suitably used as a phosphor for a light emitting device that obtains visible light by being excited with, for example, long wavelength ultraviolet rays of 330 to 390 nm.

Next, the light emitting device of the present invention will be described.
The light-emitting device of the present invention basically has a light source that emits long-wavelength ultraviolet light having a wavelength of 330 to 390 nm and the Eu ²⁺ and Mn ^{2+ of} the present invention provided at a position where light emitted from the light source can be received. It consists of a light emitting surface formed of a wavelength conversion material containing an active alkaline earth aluminate phosphor, and this light emitting surface can have various shapes such as a dot shape and a planar shape depending on the application. It is also possible to form a planar display by two-dimensionally arranging a large number of light emitting devices each having a pointed light emitting surface.

FIG. 5 illustrates a schematic cross-sectional view of an LED lamp which is one of the light emitting devices of the present invention. For example, an adhesive layer is formed on one surface of a plate-like mount lead 1 electrically connected to one electrode. 6, an ultraviolet LED chip 3 having a GaN active layer as a light source and emitting ultraviolet light having a center wavelength of 370 nm is laminated, and electrically connected to the other electrode in a non-contact state with the mount lead 1 on its side surface The inner leads 2 are juxtaposed, and the mounting lead 1 and the ultraviolet LED chip 3 and the inner lead 2 and the ultraviolet LED chip 3 are short-circuited by bonding wires 4 respectively. Then, the phosphor-containing resin lens 5 made of, for example, a lens is made of a transparent epoxy resin in which the Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphor of the present invention is dispersed and contained. The ultraviolet LED chip 3 is fixed together with the mount lead 1 and the inner lead 2 together with the mount lead 1 and the inner lead 2 together with the mount lead 1 and the inner lead 2 in the transparent resin solution. It is manufactured by immersing the entire light emitting surface and then polymerizing it into a lens shape by a method such as heating it up and heating to form the phosphor-containing resin lens 5 on the light emitting surface of the ultraviolet LED chip 3.

The light emitting device (LED lamp) of this example causes the ultraviolet LED chip 3 as a light source to emit light by energizing the electrode of the device, and the fluorescence emitted from the ultraviolet LED chip 3 is dispersed in the phosphor-containing resin lens 5. The body absorbs and exhibits blue-green or green dot-like or planar light emission.
In this case, together with the phosphor of the present invention, a phosphor that similarly absorbs light emitted from the ultraviolet LED chip 3 having a wavelength of 370 nm and emits blue and red light can emit white light when these phosphors emit light simultaneously. If the mixed phosphors are mixed at a ratio and dispersed in the phosphor-containing resin lens 5, an LED lamp having a point emission of white light emission can be obtained. Needless to say, any ultraviolet LED chip that emits ultraviolet light in the wavelength range of 330 to 390 nm can be used as the ultraviolet LED chip 3, including those that emit ultraviolet light having a wavelength of 370 nm.

In addition, a phosphor coating solution obtained by dispersing the Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphor of the present invention in a solvent containing a binder is used as a transparent material such as glass or a transparent plastic plate. A fluorescent film is formed by coating on a plate, and a light guide plate made of a light guiding material such as a transparent acrylic resin is adhered to the fluorescent film, and a long wavelength ultraviolet ray having a wavelength of 330 to 390 nm is attached to the side surface of the light guide plate. An ultraviolet LED chip or black light that emits light is placed in optical contact or proximity as a light source, and a light diffusion surface is formed on the surface opposite to the fluorescent film side of the light guide plate, excluding the fluorescent surface The light-emitting device of the present invention having a planar phosphor screen is obtained by shielding the surroundings and irradiating the phosphor screen with light emitted from the light source through the light guide plate to emit light. In the case of the light-emitting device of this example, a phosphor that emits blue and red light by absorbing light emitted from an ultraviolet LED chip that emits long-wavelength ultraviolet light having a wavelength of 330 to 390 nm together with the phosphor of the present invention as a fluorescent film. If the phosphors are formed of mixed phosphors mixed at a ratio capable of emitting white light when the phosphors emit light simultaneously, a light emitting device having a white planar phosphor screen can be obtained.

Furthermore, the planar shape comprising the Eu ²⁺ and Mn ²⁺ co-activated alkaline earth aluminate phosphor of the present invention, or a mixed phosphor of the phosphor of the present invention and a phosphor emitting light of a different emission color. The fluorescent film and an excitation light source such as an ultraviolet LED chip or a black light that emits light in the wavelength range of 330 to 370 nm are arranged facing each other at regular intervals, and the inner surface scatters light except for the fluorescent film surface. It can also be set as the structure covered with the case which is a surface.

Next, an example explains the present invention.
[ Reference Example 1]
BaCO ₃ 0.80 mol
Eu ₂ O ₃ 0.10 mol
3MgCO ₃ .Mg (OH) ₂ 0.1625 mol
MnO ₂ 0.35 mol
Al ₂ O ₃ (alpha type) 5.0 mol
AlF ₃ 0.010 mol
The above compounds are sufficiently mixed as a phosphor raw material, filled in a crucible, and a lump of graphite is placed on the raw material and covered, and the temperature is raised and lowered at a maximum temperature of 1450 ° C in a nitrogen-hydrogen atmosphere containing water vapor. It baked over 24 hours including.
Next, the calcined powder is dispersed, washed, dried and sieved, and the average particle size is 2.7 μm as measured by the Fisher Subsizer. Its composition formula is (Ba _0.8 Eu _0.2 ). The Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors of Example 1 represented by (Mg _0.65 Mn _0.35 ) · 5Al ₂ O ₃ were obtained. AlF ₃ is a flux that is often used in the manufacture of phosphors.
When the phosphor of Reference Example 1 was irradiated with 365 nm ultraviolet light and the emission luminance at that time was measured, it was 133% of the phosphor of Comparative Example 1 below measured under the same conditions.

Next, the phosphor of Reference Example 1 (green light emitting component phosphor), trivalent europium (Eu ³⁺ ) activated lanthanum oxysulfide phosphor (red light emitting component phosphor) and Eu ²⁺ activated barium magnesium aluminate phosphor ( A phosphor mixed with a blue light-emitting component phosphor) is dispersed in an epoxy polymer precursor, and a GaN-based compound semiconductor LED chip that emits ultraviolet light of 370 nm is dipped in the slurry, and the LED chip is covered with the slurry, Thereafter, the LED chip was heated together with the LED chip to be polymerized into a lens shape, and the LED lamp of Reference Example 1A having the structure illustrated in FIG. 5 in which the LED chip and the phosphor were sealed in a resin capsule was manufactured.
The mixing ratio of the phosphor of Reference Example 1, the Eu ³⁺ activated lanthanum oxysulfide phosphor and the Eu ²⁺ activated barium magnesium aluminate phosphor in the mixed phosphor was determined from the GaN-based compound semiconductor LED chip used. The mixture ratio was adjusted such that the light emission emitted white light having a light emission chromaticity of x = 0.310 and y = 0.320 according to the CIE color system.
The brightness of the LED lamp of Reference Example 1A is the same as that of Example 1 except that the phosphor of Example 1 was used instead of the phosphor of Example 1 as the green light-emitting component phosphor when lit under the same conditions. It was 112.5% of the brightness | luminance of the LED lamp of the following comparative example 1A manufactured by this.

Separately from this, the phosphor of Reference Example 1 (green light emitting component phosphor), trivalent europium (Eu ³⁺ ) activated lanthanum oxysulfide phosphor (red light emitting component phosphor) and Eu ²⁺ activated barium aluminate. A phosphor slurry was prepared by thoroughly mixing 100 parts by weight of a mixture of magnesium phosphor (blue light emitting component phosphor) and 200 parts by weight of butyl acetate containing 1.1% nitrocellulose. A fluorescent film is formed by coating and drying on the glass surface, and a black light is arranged at a position facing the fluorescent film at a certain interval, and then the inner surface is black with an envelope made of a light-reflective metal plate. A brace that covers the periphery of the fluorescent film except the fluorescent film surface opposite to the side where the light is disposed and the black light, and emits the fluorescent film upon receiving irradiation of long wavelength ultraviolet light from the black light. A scaling to produce a light-emitting device of Reference Example 1B which a light source.
When the light emitting device of Reference Example 1B was also lit under the same conditions, it was manufactured in the same manner as above except that the phosphor of Reference Example 1 was used instead of the phosphor of Reference Example 1 as the green light emitting component phosphor. The luminance of the light emitting device of Comparative Example 1B using the black light as the light source was 110.3%, which was as good as that of the LED lamp.

[Example 1 ]
BaCO ₃ 0.8075 mol
Eu ₂ O ₃ 0.07125 mol
3MgCO ₃ .Mg (OH) ₂ 0.1375 mol
MnO ₂ 0.45 mol
Al ₂ O ₃ (alpha type) 4.75 mol
AlF ₃ 0.020 mol
Except for using each of the above compounds as the phosphor material, the average particle size was 4.8 μm as measured by the Fisher Subsizer in the same manner as in Reference Example 1, and the composition formula was 0.95 (Ba _0.85). Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors of Example 1 represented by Eu _0.15 ) (Mg _0.55 Mn _0.45 ) · 4.75Al ₂ O ₃ were obtained.
When the phosphor of this Example 1 was irradiated with ultraviolet rays of 365 nm and the luminance at that time was measured, it was 121% of the emission luminance of the phosphor of the following Comparative Example 1 measured under the same conditions.
Next, instead of the phosphor of Reference Example 1, the emission chromaticity by the CIE color system is x = 0.310, y as in the LED lamp of Reference Example 1A, except that the phosphor of Example 1 is used. The LED lamp of Example 1 with == 0.320 was manufactured.
The brightness of the LED lamp of Example 1 is the same as that of Example 1 except that the phosphor of Example 1 is used instead of the phosphor of Example 1 as the green light-emitting component phosphor when lit under the same conditions. It was 110.8% of the brightness | luminance of the LED lamp of the following comparative example 1A manufactured.

[Example 2 ]
BaCO ₃ 0.7875 mol
Eu ₂ O ₃ 0.13125 mol
3MgCO ₃ .Mg (OH) ₂ 0.1875 mol
MnO ₂ 0.25 mol
Al ₂ O ₃ (alpha type) 5.25 mol
AlF ₃ 0.010 mol
Except for using each of the above compounds as the phosphor raw material, the average particle size was 3.2 μm as measured by the Fisher Subsizer in the same manner as in Reference Example 1, and the composition formula was 1.05 (Ba _0. The Eu ²⁺ and Mn ²⁺ co-activated barium magnesium aluminate phosphors of Example 2 represented by ₇₅ Eu _0.25 ) · (Mg _0.75 Mn _0.25 ) · 5.25 Al ₂ O ₃ were obtained.
When the phosphor of Example 2 was irradiated with ultraviolet rays of 365 nm and the luminance at that time was measured, the emission luminance was 119% of the phosphor of Comparative Example 1 below measured under the same conditions.
Next, instead of the phosphor of Reference Example 1, the emission chromaticity by the CIE color system is x = 0.310, y as in the LED lamp of Reference Example 1A, except that the phosphor of Example 2 is used. An LED lamp of Example 3 with == 0.320 was produced.
The brightness of the LED lamp of Example 2 was the same as that of Example 2 except that the phosphor of Example 2 was used instead of the phosphor of Example 2 as the green light-emitting component phosphor when lit under the same conditions. It was 108.2% of the brightness | luminance of the LED lamp of the following comparative example 1A manufactured.

[Comparative Example 1]
BaCO ₃ 0.416 mol
Eu ₂ O ₃ 0.042 mol
3MgCO ₃ .Mg (OH) ₂ 0.208 mol
MnO ₂ 0.168 mol
Al ₂ O ₃ (alpha type) 3.33 mol
AlF ₃ 0.015 mol
Except for using each of the above compounds as the phosphor raw material, the average particle diameter was 4.1 μm as measured by the Fisher Subsizer, as in Example 1, and the composition formula is described in Patent Document 1. Eu2 ⁺ and Mn2 ⁺ co-activated aluminate of Comparative Example 1 represented by 0.5 (Ba _0.832 Eu _0.168 ) · (Mg _0.832 Mn _0.168 ) · 3.33Al ₂ O ₃ A barium magnesium phosphor was manufactured and subjected to comparison of light emission characteristics with the phosphor of the present invention.
Next, in place of the phosphor of Reference Example 1, the emission chromaticity according to the CIE color system is x = 0.310, y as in the LED lamp of Reference Example 1A, except that the phosphor of Comparative Example 1 is used. An LED lamp of Comparative Example 1A with == 0.320 was manufactured and subjected to comparison of light emission characteristics with the LED lamp of the present invention.
Comparative Example 1B using black light as a light source in the same manner as the light emitting device of Reference Example 1B using black light as a light source, except that the phosphor of Comparative Example 1 was used instead of the phosphor of Reference Example 1 as the fluorescent film. The light emitting device was manufactured and used for comparison of light emission characteristics with the light emitting device using the backlight of the present invention as a light source.

[Comparative Example 2]
BaCO ₃ 0.5825 mol
Eu ₂ O ₃ 0.02125 mol
3MgCO ₃ .Mg (OH) ₂ 0.208 mol
MnO ₂ 0.168 mol
Al ₂ O ₃ (alpha type) 6.67 mol
AlF ₃ 0.010 mol
Except for using each of the above compounds as the phosphor raw material, the average particle diameter was 2.9 μm as measured by the Fisher Subseize Sizer in the same manner as in Reference Example 1, and the composition formula is described in Patent Document 2. Eu2 ⁺ and Mn2 ⁺ co-activated barium aluminate of Comparative Example 2 represented by 0.625 (Ba _0.932 Eu _0.068 ) · (Mg _0.832 Mn _0.168 ) 6.67Al ₂ O ₃ A magnesium phosphor was obtained.
When the phosphor of Comparative Example 2 was irradiated with 365 nm ultraviolet light and the luminance at that time was measured, the emission luminance of the phosphor of Comparative Example 1 measured under the same conditions was 70%.
Next, in place of the phosphor of Reference Example 1, the emission chromaticity by the CIE color system is x = 0.310, y as in the LED lamp of Reference Example 1A, except that the phosphor of Comparative Example 2 is used. An LED lamp of Comparative Example 2 where == 0.320 was produced.
The brightness of the LED lamp of Comparative Example 2 is the same as that of Example 1 except that the phosphor of Comparative Example 1 is used instead of the phosphor of Comparative Example 2 as the green light-emitting component phosphor when lit under the same conditions. It was 86.9% of the brightness | luminance of the LED lamp of the said comparative example 1A manufactured by this.

[Comparative Example 3]
BaCO ₃ 0.45 mol
Eu ₂ O ₃ 0.025 mol
3MgCO ₃ .Mg (OH) ₂ 0.225 mol
MnO ₂ 0.1 mol
Al ₂ O ₃ (alpha type) 4.0 mol
AlF ₃ 0.005 mol
The average particle diameter when measured with a Fisher Subsizer is 1.9 μm in the same manner as in Example 1 except that each compound is used as a phosphor raw material, and its composition formula is described in Patent Document 3. Eu2 ⁺ and Mn2 ⁺ co-activated barium magnesium aluminate of Comparative Example 3 represented by 0.5 (Ba _0.9 Eu _0.1 ) · (Mg _0.9 Mn _0.1 ) · 4Al ₂ O ₃ A phosphor was obtained.
When the phosphor of Comparative Example 3 was irradiated with 365 nm ultraviolet rays and the luminance at that time was measured, the emission luminance was 93% of the phosphor of Comparative Example 1 measured under the same conditions.
Next, instead of the phosphor of Reference Example 1, the emission chromaticity according to the CIE color system is x = 0.310, y as in the LED lamp of Reference Example 1A except that the phosphor of Comparative Example 3 is used. An LED lamp of Comparative Example 3 where == 0.320 was produced.
The brightness of the LED lamp of Comparative Example 3 was the same as that of Comparative Example 1A manufactured in the same manner as above except that the phosphor of Comparative Example 1 was used instead of the phosphor of Comparative Example 3 as the green light-emitting component phosphor. It was 100.1% of the brightness | luminance of this LED lamp.

It is a figure which illustrates the correlation with the light-emission brightness | luminance of a Eu2 ⁺ and Mn2 ⁺ co-activation barium magnesium aluminate fluorescent substance, and fluorescent substance base composition. It is a figure which illustrates the correlation with the light-emission brightness | luminance of a Eu2 ⁺ and Mn2 ⁺ co-activation barium magnesium aluminate fluorescent substance, and fluorescent substance base composition. It is a diagram illustrating the correlation between the number of moles of emission luminance and activator Mn of Eu ²⁺ and Mn ²⁺ coactivated barium magnesium aluminate phosphor. Is a diagram illustrating the correlation between the number of moles of emission luminance and activator Eu of Eu ²⁺ and Mn ²⁺ coactivated barium magnesium aluminate phosphor. It is a schematic sectional drawing which shows one example of the light-emitting device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mount lead 2 Inner lead 3 Ultraviolet LED chip 4 Bonding wire 5 Phosphor containing resin lens 6 Adhesive layer

Claims (7)

The composition formula is represented by _{a (P 1-x Eu x} ) O · (Mg 1-y Mn y) O · bAl 2 O 3, emits green light when irradiated with long-wave ultraviolet light in the wavelength range of 330~390nm An alkaline earth aluminate phosphor for exciting long wavelength ultraviolet light. (In the formula, P is Ba, represents at least one alkaline earth metal element in the Sr and Ca, a, b, x and y are 0.8 ≦ a ≦ 1.2,4.0 ≦ respectively It represents a number satisfying b ≦ 6.0, 0.10 ≦ x ≦ 0.35 and 0.15 ≦ y ≦ 0.50, provided that the a value is 1.0 and the b value is 5.0. Except when ). 2. The alkaline earth aluminate phosphor for long wavelength ultraviolet excitation according to claim 1, wherein the a value and the b value are numbers satisfying 0.36 ≦ (1 + a) /b≦0.44. 2. The alkaline earth aluminate phosphor for long wavelength ultraviolet excitation according to claim 1, wherein the x value is in a range of 0.15 ≦ x ≦ 0.25 . 2. The alkaline earth aluminate phosphor for long-wavelength ultraviolet excitation according to claim 1 , wherein the y value is in the range of 0.25 ≦ y ≦ 0.45 . A light emitting device comprising at least a light source that emits long-wavelength ultraviolet light in a wavelength range of 330 to 390 nm and a wavelength conversion material that absorbs at least a part of light emitted from the light source and emits light having a wavelength different from that of the light source. A light-emitting device, wherein the wavelength converting material includes the alkaline earth aluminate phosphor for long-wavelength ultraviolet excitation according to any one of claims 1 to 4 . It said light source according to any one of claims 1-4, characterized in that the long-wave ultraviolet light in the wavelength region is a light emitting diode having a light emitting chip of a nitride-based compound semiconductor layer that emits the 330~390nm Light emitting device. The light emitting device according to any one of claims 1-4, wherein the light source is a black light that emits long-wave ultraviolet light in the wavelength range 330～390Nm.

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