WO2010010947A1 - Aluminate phosphor, method for producing the same, fluorescent lamp using the phosphor and liquid crystal display - Google Patents

Abstract

Disclosed is an aluminate phosphor represented by the following general formula: (Ce_xTb_1-x)₂O₃·y(Mg_1-zMn_z)O·nAl₂O₃ (wherein x, y, z and n represent numbers satisfying the following relations: when 0 < x < 1, 0.6 ≤ y ≤ 1.8, 0 ≤ z ≤ 1 and 7 ≤ n, or alternatively when x = 1, 0.2 ≤ y ≤ 1.8, 0.1 ≤ z ≤ 1 and 7 ≤ n). The aluminate phosphor has  significantly improved luminance and a significantly shortened 1/10 afterglow time when compared with conventional phosphors.  In addition, the aluminate phosphor can reduce the use of Tb which is a rare element. The phosphor is suitably used for fluorescent lamps for illumination or backlight lamps.  In particular, a liquid crystal display device having excellent moving picture characteristics can be provided by using a phosphor having a short 1/10 afterglow time as a backlight lamp and making the phosphor emit light intermittently.

Description

Aluminate phosphor, method for producing the same, and fluorescent lamp and liquid crystal display device using the phosphor

The present invention relates to an aluminate phosphor exhibiting green light emission with higher brightness than conventional under excitation by ultraviolet rays and vacuum ultraviolet rays (particularly 180 nm to 300 nm).
In particular, when Mn is used as a base material for green light emission, the light emission intensity is about twice that of conventional phosphors. Moreover, due to the structure, Eu / Mn co-activated barium / magnesium is currently available. The present invention relates to an Mn-activated aluminate phosphor having a longer life than an aluminate phosphor (hereinafter referred to as BAM phosphor) (BAM: Eu, Mn), and a method for producing the phosphor.

The present invention also relates to a fluorescent lamp, particularly preferably a cold cathode fluorescent lamp, using such an aluminate phosphor and having excellent luminance and color reproduction range.
The present invention also relates to a Tb-activated cerium / magnesium / aluminate phosphor exhibiting high-brightness green light emission equivalent to or higher than that of a conventional phosphor and a Tb / Mn co-activated cerium / magnesium / aluminate phosphor.
In addition, the present invention has an afterglow in the afterglow time and material cost reduction while having almost the same brightness as the conventional one under excitation by ultraviolet rays and vacuum ultraviolet rays, particularly 180 nm to 300 nm. The present invention relates to a Tb-activated cerium-magnesium-aluminate phosphor that emits green light.
Furthermore, the present invention relates to a fluorescent lamp having a short afterglow time, particularly preferably a cold cathode fluorescent lamp, using these phosphors.
The present invention relates to a display using these phosphors, and particularly to a display using a backlight unit using a cold cathode fluorescent lamp using these phosphors.

Conventional aluminate-based green phosphors include Tb-activated cerium / magnesium / aluminate phosphors (hereinafter referred to as CAT phosphors) and Eu / Mn co-activated barium / magnesium / aluminate phosphors. The body is known. However, the price of Tb has increased remarkably in recent years, and it has been difficult to avoid the decrease in color purity due to the emission of Tb sub-light, and the BAM phosphor has problems such as a short lifetime.
On the other hand, as an aluminate phosphor that exhibits high-luminance green light emission by ultraviolet excitation, for example, Mn-activated cerium / magnesium / aluminate fluorescence whose composition is CeMg _0.75 Mn _0.25 Al ₁₁ O ₁₉ or the like And an aluminate phosphor obtained by substituting a part of Mg of the phosphor with another divalent metal element (for example, see Patent Documents 2 to 4).

However, there is a demand for the development of phosphors that always emit light with higher brightness than conventional products. For example, cold cathode fluorescent lamps (in which rare gases such as Ar and Xe are enclosed in a tube in addition to mercury, Development of phosphors that produce green light emission that is brighter and brighter than conventional phosphors for green phosphors used for fluorescent films of lamps that excite phosphors by ultraviolet rays generated by electric discharge or vacuum ultraviolet rays) Is desired.

By the way, the above-mentioned Mn-activated cerium / magnesium / aluminate phosphor emits light in the near ultraviolet region (around 350 nm) derived from Ce when Mn is not activated originally. In addition, Mn is excited by receiving energy from Ce, and emits light having a peak in the green wavelength region (around 518 nm) derived from divalent Mn. Therefore, in this Mn-activated cerium / magnesium / aluminate phosphor, in order to obtain high luminance green light emission by excitation with ultraviolet rays (particularly 180 nm to 300 nm), the energy absorbed by the trivalent Ce is efficiently Mn. Need to be reabsorbed (ie energy transfer).
Therefore, the light emission in the near-ultraviolet region derived from Ce is light emission in which energy was not transferred from Ce to Mn, and is not visible to the naked eye and does not contribute to the light emission intensity. There was also a request to increase the luminescence intensity.

Further, as one of aluminate-based green light emitting phosphors having a structure similar to that, the above-described Tb-activated cerium / magnesium / aluminate phosphor (hereinafter also referred to as CAT phosphor) or Tb / Mn Co-activated cerium / magnesium / aluminate phosphors (hereinafter also referred to as CAT: Mn phosphors) are known.
The stoichiometric composition of these known CAT phosphors << (Ce, Tb) MgAl ₁₁ O ₁₉ >> and CAT: Mn phosphors << (Ce, Tb) (Mg, Mn) Al ₁₁ O ₁₉ >> is usually (Ce + Tb). : Mg or (Ce + Tb) :( Mg + Mn) is approximately 1: 1 (that is, the ratio of each mole of Ce + Tb and Mg in the phosphor composition, or the ratio of each mole of Ce + Tb and Mg + Mn is substantially equal). It is.

For example, Patent Document 5 proposes a CAT: Mn phosphor having a composition of (Mg _1-a Mn _a ) O.xAl ₂ O ₃ .yCe ₂ O ₃ zTb ₂ O ₃ , While changing (Ce + Tb) :( Mg + Mn) to 1: 1, an attempt is made to change the brightness by increasing the amount of Mn substitution.

In Patent Document 6, a part of Ce having a composition of (1 / 2-xy) Ce ₂ O ₃ .xLa ₂ O ₃ .yTb ₂ O ₃ .MgO.pAl ₂ O ₃ is replaced with La. In a CAT phosphor capable of increasing the p-value (amount of Al ₂ O ₃ ) from the stoichiometric composition, it can be compared with the stoichiometric composition or a slightly higher luminous flux can be obtained. It is disclosed.
Needless to say, there is a demand for the development of a phosphor that emits green light with higher brightness than the conventional phosphors that are activated with Tb or Tb and Mn.

More recently, green phosphors are required to have a shorter afterglow in addition to an improvement in luminance.
That is, a liquid crystal display (LCD) forms an image on a panel by a combination of a backlight and a liquid crystal shutter, and further enables color display of the image by combining a color filter.

LCD is a hold display in which all pixels are displayed at the same time and always displayed until one frame of video is replaced with the next frame. In this hold display, the afterimage feeling does not disappear due to the characteristic of the human eye to feel the afterimage, and the image with a strong afterimage is only displayed in a motion picture such as a sports program.

Incidentally, the number of frames displayed per second for television signals in the world is about 50 to 60 frames. In Japan, 60 frames per second is common, and the display time for one frame is about 16 msec. Due to advances in technology, the response speed of liquid crystals is shorter than 16 msec and the afterimage feeling is being reduced. However, just increasing the response speed has little effect, and even if the response speed can be reduced to 0 msec, the afterimage feeling Will not disappear.
As described above, LCDs are required to have moving image characteristics similar to those of a color cathode ray tube (CRT) that performs impulse-type display, particularly in an image with intense movement.

In order to eliminate the afterimage on LCD, for example, the display, which was 60 frames per second in the past, is doubled to 120 frames, the held image is shortened to half of 8 msec, and the video signal for one frame is input. Each time, full-screen black display is performed, backlight emission timing is selectively performed, or both are combined to realize a pseudo-impulse display, thereby providing a moving image characteristic close to that of a CRT. It has gained.

On the other hand, in order to reduce the afterimage feeling and contour blur of the LCD, attempts have been made to blink a cold cathode fluorescent lamp (CCFL) used for a backlight in synchronization with a full screen black display. As the frame frequency, which was 60 Hz, has recently become faster to 120 Hz or higher, the CCFL lighting time / light-off time has become shorter. For this reason, the phosphor used in the CCFL is also required to be developed with the shortest afterglow time.
Conventionally, three-wavelength fluorescent lamps have been used as CCFLs for liquid crystal backlights, and these three-wavelength fluorescent lamps emit light that is strong and has a narrow half-value width in the vicinity of each wavelength region of 450, 540, and 610 nm. Blue, green and red phosphors with spectral peaks are used.

The 1/10 afterglow time of europium-activated yttrium oxide phosphor (hereinafter also referred to as YOX phosphor), which is a typical CCFL red phosphor, is approximately 3.0 ms. One europium-activated barium magnesium aluminate phosphor (hereinafter also referred to as BAM phosphor) has a 1/10 afterglow time of approximately 1.0 ms or less, while it is a typical green color that is currently widely used for CCFLs. The 1/10 afterglow time of the phosphors Ce and Tb co-activated lanthanum phosphate phosphors (hereinafter also referred to as LAP phosphors) is 7.4 ms.
Among these red, blue, and green phosphors, the afterglow time of the green phosphor is particularly long compared to the other two colors, and the green emission in the wavelength region of 540 nm has high relative visibility, so that the afterglow of green There was a problem of being conspicuous.

On the other hand, as a green phosphor other than the LAP phosphor, an aluminate-based Tb / Mn co-activated cerium / magnesium / aluminate phosphor (hereinafter also referred to as CAT: Mn phosphor) or a Tb-activated phosphor. Cerium / magnesium / aluminate phosphors (hereinafter also referred to as CAT phosphors) are known.

However, the CAT: Mn phosphor as described in Patent Document 7 is not suitable for LCD backlights that require a relatively long afterglow of light emission and a short afterglow, similar to the LAP phosphor. .
Regarding the CAT phosphor, for example, according to Non-Patent Document 1, from the viewpoint of brightness, Ce: Tb = 2: 1 (ie Ce / Tb = 2.0), Mg: (Ce + Tb) = 1: 1 (ie Mg / (Ce + Tb) = 1.0) is said to be optimal, but such a ratio was not satisfactory with respect to 1/10 afterglow time.
In this specification, the 1/10 afterglow time is required until the emission intensity immediately after the phosphor is irradiated with ultraviolet rays to emit light and the excitation light is cut off to 1/10 brightness. It's time.

JP 49-77893 A Japanese Patent No. 2663306 JP-A-4-255790 JP 2000-169844 A JP 56-86983 A Japanese Patent Publication No.57-61068 JP 2008-308634 A

The present invention exhibits green light emission with higher brightness than conventional products under vacuum ultraviolet light or ultraviolet light excitation, and has a higher emission intensity in the visible light region than the conventional product and absorption of mercury rays. Another object of the present invention is to provide an excellent Mn-activated aluminate phosphor, a method for producing the phosphor, a general illumination lamp using the phosphor, and a cold cathode fluorescent lamp.
Another problem of the present invention is that Tb-activated cerium / magnesium / aluminate phosphor and Tb / Mn coexisting that emit green light with high brightness equal to or higher than that of the conventional one under vacuum ultraviolet light or ultraviolet light excitation. It is to provide an active cerium / magnesium / aluminate phosphor.

Furthermore, the problem of the present invention is that the afterglow time is remarkably shortened while having almost the same brightness as that of the conventional one under excitation by ultraviolet rays and vacuum ultraviolet rays, particularly 180 nm to 300 nm. To provide a Tb-activated cerium / magnesium / aluminate phosphor exhibiting green light emission, a method for producing the phosphor, and a cold cathode fluorescent lamp using the phosphor capable of realizing material cost reduction. Let it be an issue.

In order to solve the above-mentioned problems, the present inventors first studied in detail the relationship between the composition of a conventional Mn-activated cerium / magnesium / aluminate phosphor and light emission characteristics such as luminance. As a result, the stoichiometric composition of a conventional similar aluminate phosphor (hereinafter referred to as a composition in which Ce: Mg + Mn of a conventionally known Mn-activated cerium / magnesium / aluminate phosphor is approximately 1: 1) Is abbreviated as “stoichiometric composition”), the absorption of excitation light such as mercury rays is improved nearly twice and the efficiency of energy transfer from Ce to Mn is improved (Ce). The intensity ratio of the light emission near 350 nm derived from Mn and the light emission near 517 nm derived from Mn has changed in the direction in which the light emission from Mn increases), the present invention has found that the luminance of the green light emission is remarkably improved. It came to.

As described above, the Mn-activated aluminate phosphor of the present invention (hereinafter also simply referred to as “aluminate phosphor” of the present invention) has a chemical content ratio of each metal element constituting the phosphor. Fluorescence that has excellent properties due to deviation from the stoichiometric composition, and this deviation from the stoichiometric composition (non-stoichiometry) brings about changes in the crystal structure and optical properties (luminescence characteristics) of the phosphor. Presumed to be a body.
The present inventors have found that this finding is not limited to phosphors activated only by Mn, but high brightness can be achieved even with phosphors activated only by Mn and Tb or Tb.

As a result of further detailed examination,
(Α) Decreasing the amount (mole) of Tb relative to Ce in the phosphor, that is, Ce / Tb> 2.0 (molar ratio).
(Β) Decreasing the amount (mole) of Mg relative to (Ce + Tb) in the phosphor, that is, Mg / (Ce + Tb) <1.0 (molar ratio).
(Γ) Combining such a decrease in Tb amount and a decrease in Mg amount,
As a result, it was found that a green phosphor having substantially the same brightness as that of the conventional one and having a long afterglow time can be obtained.

Furthermore, the present inventors have also found that when this green phosphor is used in a white fluorescent lamp, a decrease in brightness can be further suppressed.
This is because when the amount of Tb in the phosphor decreases, the Ce emission increases and the Tb emission decreases, so that the luminance tends to decrease. However, the Ce emission reduces the other color phosphor (red phosphor, blue phosphor). This is probably because the white lamp does not have a very low luminance for excitation.

In addition, as described above, in order to reduce the afterimage feeling and blurring of the outline, LCDs are going to adopt a method of blinking the backlight and further shortening the blinking interval of the backlight. Since it is necessary for the brightness to rise instantaneously, a phosphor having a short decay time (afterglow time) also has a short rise time, which is considered to work favorably on the brightness.

The present invention has been made based on such knowledge, and the gist thereof is as follows.
(1) General formula;
_{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3
(However, in the formula, x, y, z and n are numbers satisfying the conditions of 0.6 ≦ y ≦ 1.8, 0 ≦ z ≦ 1, and 7 ≦ n, respectively, when 0 <x <1. , X = 1, 0.2 ≦ y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n. .
(2) The aluminate phosphor according to (1), wherein x = 1 and 0.3 ≦ y ≦ 1.2 in the general formula.
(3) The aluminate phosphor according to (2) above, wherein x = 1 and 0.7 ≦ y ≦ 1.2 in the general formula.
(4) The aluminate phosphor according to any one of (2) and (3) above, wherein n in the general formula is 12 ≦ n ≦ 40.
(5) A phosphor composed of at least cerium (Ce), manganese (Mn), magnesium (Mg), aluminum (Al), and oxygen (O), and an emission intensity of 518 nm when excited by ultraviolet light having a wavelength of 254 nm The aluminate phosphor, characterized in that the ratio of the emission intensity at 350 nm to less than 15%.
(6) The phosphor has the general _{formula; (Ce x Tb 1-x} ) is represented by _{2 O 3 · y (Mg 1} -z Mn z) O · nAl 2 O 3, and in the general formula, x, y , Z and n are numbers satisfying the conditions of x = 1, 0.2 ≦ y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n, respectively. Aluminate phosphor.
(7) The aluminate phosphor according to (1), wherein x is 0 <x <1 and y is 0.8 ≦ y ≦ 1.6 in the general formula .
(8) The aluminate phosphor according to (7), wherein x is 0.5 ≦ x ≦ 0.9 in the general formula.
(9) The aluminate phosphor according to any one of (1) to (3), wherein in the general formula, n is 11 ≦ n.
(10) The aluminate phosphor according to any one of (7) to (9), wherein z in the general formula is z = 0.
(11) The aluminate phosphor according to (1), wherein in the general formula, 0.68 ≦ x ≦ 0.95 and z = 0.
(12) The aluminate phosphor according to (11), wherein 0.7 ≦ x ≦ 0.85 in the general formula.
(13) A phosphor composed of at least cerium (Ce), terbium (Tb), magnesium (Mg), aluminum (Al) and oxygen (O), and having a 1/10 afterglow time of 6.4 ms or less. An aluminate phosphor characterized by
(14) The aluminate phosphor according to any one of (1) to (13), wherein the surface is coated with a coating substance.
(15) The aluminate phosphor according to (14), wherein the coating material is a rare earth metal carbonate.
(16) The aluminate phosphor according to (15) above, wherein a coating amount of the rare earth metal carbonate is 0.05 to 5% by weight with respect to the phosphor.
(17) Ce compounds, Tb compounds, Mg compounds, Mn compounds, and Al compounds are stoichiometrically represented by the above formulas (1) to (4) and (6) with respect to Ce, Tb, Mg, Mn, and Al. ) To (12). A method for producing an aluminate phosphor, comprising mixing and firing at a ratio described in any one of the above.
(18) Ce compound that can be changed to oxide of cerium (Ce) by heating, Tb compound that can be changed to oxide of terbium (Tb) by heating, Mg compound that can be changed to oxide of magnesium (Mg) by heating, The Mn compound that can be changed to an oxide of manganese (Mn) and the Al compound that can be changed to an oxide of aluminum (Al) by heating are represented by the above stoichiometric composition formulas for Ce, Tb, Mg, Mn, and Al. A method for producing an aluminate phosphor, comprising mixing and firing at a ratio according to any one of (1) to (4) and (6) to (12).
(19) A fluorescent lamp using the aluminate phosphor according to any one of (1) to (16) above.
(20) The fluorescent lamp as described in (19) above, wherein the fluorescent lamp is a cold cathode fluorescent lamp.
(21) As the green phosphor, the aluminate phosphor according to any one of claims 1 to 16,
As a blue phosphor, a phosphor having a 1/10 afterglow time of 1.0 ms or less is used as a red phosphor, and a phosphor having a 1/10 afterglow time of 3.0 ms or less is used as a phosphor film. Cold cathode fluorescent lamp.
(22) The blue phosphor is Eu-activated strontium / calcium apatite phosphor or Eu-activated barium / magnesium aluminate phosphor, and the red phosphor is Eu-activated yttrium oxide phosphor or Eu-activated vanadium. The cold cathode fluorescent lamp according to (21), which is an yttrium acid phosphor.
(23) A backlight unit using the fluorescent lamp according to (19) or (20) or the cold cathode fluorescent lamp according to (21) or (22).
(24) A liquid crystal display device that is driven by pseudo impulse using the backlight unit according to (23).

In the aluminate phosphor of the present invention, each component element constituting the matrix itself is composed of the same components as the conventional phosphor, but the component ratio of each component element is different from that of the conventional one. As a result, green light emission with higher luminance than the conventional one can be obtained.
In addition, since the ratio of the relatively inexpensive Al ₂ O _{3 to} the base component is high and the ratio of the relatively expensive Tb to the base component is low, there is an advantage that the manufacturing cost is reduced.
Further, when Mn is used as a main green light-emitting activator (especially when x = 1), the light emission intensity in the green region is higher than that in the ultraviolet region that cannot be seen with the naked eye and does not contribute to luminance. Can be.
And the phosphor of this invention can also make the afterglow remarkably short with respect to the conventional green light emission fluorescent substance.

The phosphor of the present invention can be used as a fluorescent lamp as a substitute for a conventional Tb-activated lanthanum phosphate phosphor.
In particular, in the cold cathode fluorescent lamp, by using the aluminate phosphor of the present invention, a cold cathode fluorescent lamp having a higher luminous flux and an improved luminous flux maintenance factor can be obtained.
In particular, in the case of the cold cathode fluorescent lamp using the aluminate phosphor of the present invention (when Z ≠ 0) using Mn as a green light emitting activator, the color reproduction range is the conventional Tb activated green phosphor. And a color reproduction range of a TV or the like can be expanded.

Further, the afterglow time as a cold cathode lamp can be remarkably shortened. In particular, when used for a liquid crystal display device driven intermittently, a liquid crystal display device with little afterimage feeling can be obtained.
Note that the aluminate phosphor of the present invention is recognized not only for cold cathode fluorescent lamps but also for excellent characteristics when applied to vacuum ultraviolet light emitting devices such as plasma displays utilizing excitation in the vacuum ultraviolet region.
Moreover, it can use suitably also for LED etc. by selecting suitably the excitation wavelength of the light source for excitation used in combination with the fluorescent substance of this invention.

(A) is a general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1) in the aluminate phosphor represented It is the graph which showed the correlation with y in general formula at the time of exciting with the ultraviolet-ray with a wavelength of 254 nm, emission intensity (♦) of emission wavelength 518nm, and emission intensity (▲) of emission wavelength 350nm. (B) is a graph showing the correlation between y and the ratio of the emission intensity at an emission wavelength of 350 nm to the emission intensity at an emission wavelength of 518 nm. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1) y of the general formula in aluminate phosphor represented by And the ratio of the excitation intensity at 254 nm to the excitation intensity at 172 nm. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1) y of the general formula in aluminate phosphor represented by It is the graph which showed the correlation with brightness | luminance. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) n in the general formula in O · nAl ₂ O ₃ (provided that x = 1) in the aluminate phosphor represented It is the graph which showed the correlation with brightness | luminance. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1) n and FSSS method in aluminate phosphor represented by ( It is the graph which showed the correlation with the average particle diameter of a Fisher subsieve sizer method. General _formula: and _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) y and luminance in aluminate phosphor represented by O · nAl ₂ O ₃ (provided that z = 0) And a correlation between n and luminance. 6 is a graph illustrating emission spectra of phosphors in Examples 30 to 34 and Comparative Example 6. It is the graph which expanded the main peak of the graph shown in FIG. It is a graph which illustrates each emission spectrum of the fluorescent substance of Examples 38 and 39 and Comparative Examples 8 and 9. It is a graph which illustrates each excitation spectrum of the fluorescent substance of Examples 38 and 39 and Comparative Examples 8 and 9. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that z = 0) x of the general formula in aluminate phosphor represented by And a 1/10 afterglow time. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that z = 0) x of the general formula in aluminate phosphor represented by It is the graph which showed the correlation with brightness | luminance. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that z = 0) y of the general formula in aluminate phosphor represented by And a 1/10 afterglow time. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that z = 0) y of the general formula in aluminate phosphor represented by It is the graph which showed the correlation with brightness | luminance. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) n in the general formula in O · nAl ₂ O ₃ (provided that z = 0) with an aluminate phosphor represented And a 1/10 afterglow time. Formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) n in the general formula in O · nAl ₂ O ₃ (provided that z = 0) with an aluminate phosphor represented It is the graph which showed the correlation with brightness | luminance.

Aluminate phosphor of the present invention have the general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( where in the formula, x, y, z And n are numbers satisfying the conditions of 0.6 ≦ y ≦ 1.8, 0 ≦ z ≦ 1, and 7 ≦ n when 0 <x <1, respectively, and 0.2 ≦ when x = 1 y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n).
The phosphor of the present invention is expressed by one general formula, and has common features such as significantly improved luminance as compared with conventional phosphors.

Below, (1) When Mn is mainly used as an activator, (2) When Tb and Mn are used as an activator, (3) Mainly using Tb as an activator, 1/10 remaining Three preferred embodiments where the light time can be made extremely short will be described.

(First embodiment of the present invention)
First aluminate phosphor suitable for embodiments of the present invention have the general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1), where y, z and n are numbers satisfying the conditions of 0.2 ≦ y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n, respectively. Features.
That is, the aluminate phosphor according to the first embodiment of the present invention has a ratio of manganese, magnesium, and aluminum from the stoichiometric composition of the conventional Mn-activated cerium / magnesium / aluminate phosphor, X, y, z, and n in the above general formula are adjusted within such a range according to the luminance of green light emission, desired chromaticity, the intensity ratio between light emission in the near ultraviolet region and light emission in the green region, and the like. It is important to.
The stoichiometric composition of a conventional Mn-activated cerium / magnesium / aluminate phosphor (Ce: Mg + Mn is approximately 1: 1) is a y value of 2 in the above general formula, and z is an arbitrary number. Yes, n value is 11.

The aluminate phosphor according to the first embodiment of the present invention is characterized in that the total amount of manganese and magnesium with respect to Ce is reduced as compared with the above stoichiometric composition. If y in the above general formula (total ratio of manganese and magnesium in the phosphor) is less than 0.2, it is difficult to obtain sufficient light emission. On the other hand, if it exceeds 1.8, it will approach the conventional stoichiometric composition, and an improvement in light emission luminance cannot be achieved. The preferable range of the y value is 0.3 ≦ y, y ≦ 1.2, and more preferably 0.7 ≦ y and y ≦ 1.2.

And z in the above general formula (ratio of Mn in Mg + Mn in the phosphor) may be appropriately selected within the range of 0.1 ≦ z ≦ 1, but if it is less than 0.1, the amount of Mn is small. If too much light is not obtained and more intense light emission is desired, 0.2 or more, particularly preferably 0.4 or more is preferable. On the other hand, a large amount of Mn is unlikely to be a big problem. However, when deeper green is obtained as the chromaticity (when a wide color reproduction range is obtained), 0.9 or less is preferable, and the chromaticity is obtained according to NTSC (National Vision System Committee) coordinates. Is most preferably 0.9 or more.

In the aluminate phosphor according to the first embodiment of the present invention, n in the general formula is 7 or more. If this n value (x = 1, the blending ratio of Al ₂ O ₃ to Ce ₂ O ₃ in the phosphor) is less than 7, the luminance characteristics are likely to deteriorate.
As described above, in the aluminate phosphor according to the first embodiment of the present invention, the amount of Al ₂ O ₃ can be increased as compared with the known composition described in Patent Document 1 described above.
When the n value is 12 or more, the shape of the phosphor crystal changes from a flat plate shape to a shape closer to a sphere than the thickness is increased. It is easy to match the phosphor, and it is difficult to produce a color difference at the end of the tube. In addition, it is advantageous in terms of filling properties, and it is easy to obtain a sufficient amount of light as a lamp. On the other hand, since the luminance gradually decreases when it exceeds 40, the n value is preferably 12 ≦ n ≦ 40, more preferably 12 ≦ n ≦ 30, and particularly preferably 12 ≦ n ≦ 20. .

The aluminate phosphor according to the first embodiment of the present invention may contain other elements in the composition thereof within a range that does not greatly exclude the effects of the present invention. As for Mg in the range, there is no problem even if a small amount is substituted by a divalent metal such as Sr or Ba whose ionic radius is close to that of Mg within a range that does not greatly impair the effect of the present invention. A small amount of Y, Gd, La, etc. may be substituted, and a part of Al may be replaced by Ga and / or Sc.

The composition of the aluminate phosphor according to the first embodiment of the present invention can be confirmed by ICP emission spectroscopy (Inductively Coupled Plasma).
The aluminate phosphor according to the first embodiment of the present invention is presumed to have a change in crystal structure because its composition is significantly different from that of the conventional stoichiometric composition. It is not yet clear, however, according to preliminary measurements, it seems that the a-axis direction is contracted and the c-axis direction is extended as compared with the conventional stoichiometric composition.

That is, J. Electrochem. Soc. SOLID-STATE SCIENCE AND TECHNOLOGY May 1976 Vol. 123 No. 5 P691 includes CeMgAl ₁₁ O ₁₉ (= Ce ₂ O ₃ .2 (Mg) O.11Al ₂ O ₃ ) The axis is 5.61 nm, the c-axis is 21.99 nm, the a-axis of CeMnAl ₁₁ O ₁₉ (= Ce ₂ O ₃ · 2 (Mn) O · 11Al ₂ O ₃ ) is 5.62 nm, and the c-axis is 21.96 nm. The c-axis length / a-axis length is 3.92 or less. In comparison, in the phosphor structure of the present invention where n is 12 or more, the a-axis is 5.58 nm or less, the c-axis is 22.00 nm or more, and the c-axis length / a-axis length is 3.93 or more, Particularly preferably, the c-axis length / a-axis length is 3.94 or more.

As an aspect viewed from the characteristics of the aluminate phosphor according to the first embodiment of the present invention, the ratio of the emission intensity at 350 nm to the emission intensity at 518 nm is preferably less than 15%. Since the light emission intensity ratio of a normal stoichiometric composition is slightly over 20%, it can be seen that energy transfer from Ce to Mn is efficiently performed in the aluminate phosphor of the present invention.

Hereinafter, description will be made using data.
In the aluminate phosphor according to the first embodiment of the present invention, as shown in Table 1, Ce, Mn, and Al are fixed to a certain amount, and when the amount of Mg is varied, ultraviolet rays with a wavelength of 254 nm are used. FIG. 1A shows changes in emission intensity (♦) with an emission wavelength of 518 nm and emission intensity (▲) with an emission wavelength of 350 nm when excited. Incidentally, y in Table 1, and z, y in the general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( provided that x = 1) The numerical values other than y and z are the number of moles of each constituent element.

In addition, FIG. 1B shows the intensity ratio of light emission with a light emission wavelength of 350 nm to light emission with a light emission wavelength of 518 nm, which is generated based on the data of FIG.
Incidentally, FIG. 1 (A), the and in each graph of (B), the general formula x-axis _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 It represents the value of y in (where x = 1). Therefore, the stoichiometric composition means that the Mn amount is 0.21 mol and the Mg amount is 0.79 mol << in the above general formula, y = 2, z = 0.21, n = 11, that is, Ce ₂ O _3. • 2 (Mn _0.21 , Mg _0.79 ) O · 11Al ₂ O ₃ aluminate phosphor ”.
Thus, from FIGS. 1A and 1B, when y is shifted from the stoichiometric composition (y = 2.0) in the direction of decreasing y, the emission intensity in the near ultraviolet region derived from Ce is reduced. It can be seen that the emission intensity in the Mn-derived green light region is significantly increased.

In addition, the aluminate phosphor according to the first embodiment of the present invention has not only improved energy transfer from the above-mentioned Ce to Mn, but also mercury as compared with the conventional stoichiometric composition. Absorption for luminescence is also improved.

FIG. 2 shows this. While conventional phosphors of stoichiometric composition show almost the same excitation spectrum intensity in the range of VUV (Vacuum Ultra-Violet light) (172 nm) and emission of mercury rays (mainly 254 nm), In the phosphor of the present invention shifted from the stoichiometric composition (y = 2.0) in the direction of decreasing y, it can be seen that the excitation with mercury rays is improved to nearly twice that of excitation with VUV. .

The method for producing the aluminate phosphor according to the first embodiment of the present invention is not particularly limited as long as the method usually used for producing the phosphor is used. Preferably, the Ce compound, the Mg compound, the Mn compound, and the Al compound are stoichiometrically combined with the composition ratio of the aluminate phosphor in which the composition ratio of Ce, Mg, Mn, and Al is related to the first embodiment. What is necessary is just to mix and bake so that it may correspond. More preferably, a Ce compound that can be converted to an oxide of cerium (Ce) by heating, an Mg compound that can be converted to an oxide of magnesium (Mg) by heating, an Mn compound that can be converted to an oxide of manganese (Mn) by heating, and It is mixing and baking the Al compound which can be changed into the oxide of aluminum (Al) by heating.
Examples of the phosphor material preferably used in the present invention include cerium carbonate, cerium oxide, magnesium carbonate, magnesium oxide, manganese carbonate, manganese oxide, alumina, and the like, and other salts that easily become oxides when heated. It is done.

A specific method for producing an aluminate phosphor according to the first embodiment of the present invention can be performed, for example, by the following procedure.
(1) A predetermined amount of the raw materials as described above are weighed and sufficiently mixed by a mixing means using a ball mill, a V-type mixer or the like.
(2) The obtained mixture is filled in a heat-resistant container such as an alumina crucible and fired at 1400 to 1600 ° C. in a reducing atmosphere for 10 to 26 hours in a high temperature furnace including the time required for raising and lowering the furnace temperature.
(3) The obtained fired product is subjected to the same dispersion, washing, and drying treatments as in the post-treatment step applied during normal phosphor production.

In the present invention, as in the case of obtaining a known aluminate phosphor in a mixture of phosphor raw material compounds subjected to firing, a fluoride such as aluminum fluoride or boric acid or boron oxide is used for promoting the reaction. Etc. can be added as a flux.
The particle diameter of the aluminate phosphor according to the first embodiment of the present invention is not particularly limited, but when applied to the fluorescent film of the cold cathode fluorescent lamp of the present invention, handling and color uniformity are not limited. From this point, the FSSS particle size may be arbitrarily selected from the range of about 1 to 20, preferably 2 to 8, more preferably 2 to 7.

The fluorescent lamp of the present invention is manufactured in the same manner as a conventional fluorescent lamp except that the aluminate phosphor of the present invention thus obtained is used as a fluorescent film. The same applies to a cold cathode fluorescent lamp (including an external electrode type).
That is, the aluminate phosphor according to the first embodiment of the present invention includes, for example, water or butyl acetate together with a binder such as low melting glass powder, fine metal oxide, or fine metal borate or phosphate, Prepare a phosphor coating slurry by suspending it in an organic solvent such as isopropyl alcohol, apply it to the inner wall of the glass tube, and dry it to form a phosphor film. Stop and attach electrodes. Of course, at this time, it is obvious that phosphors of other colors can be mixed and used in white.

The aluminate phosphor according to the first embodiment of the present invention and the fluorescent lamp using the same are preferably used for general illumination, and the color reproduction range is a conventional cold cathode fluorescent lamp (usually blue). Compared with BAM phosphor, LAP phosphor as green, and YOX (yttrium oxide) phosphor as red), a wide range can be reproduced.

When the phosphor of the present invention is used as a fluorescent lamp for illumination, it is usually mixed with blue and red phosphors to emit white light. The phosphor used at this time can be used by diverting one used in combination with a conventional LAP phosphor. For example, as a material emitting blue light, Eu-activated BAM or SCA phosphor can be used. When used as a lamp for illumination, a lamp having a wide half-value width of the emission spectrum is preferably used. For this reason, for example, BAM to which Mn or Sr is added, or SCA to which the blending amount of Sr, Ba, Ca, Mg or the like is appropriately changed is preferably used. As red, Y2O3: Eu, Y (P, VO) 4: Eu, or the like is preferably used. If necessary (for example, lighting for meat), 3.5MgO.0.5MgF2 is used as a deep red phosphor. -It is also preferable to add GeO2: Mn or the like. Of course, the phosphor of the present invention may be used as a rare gas lamp instead of mercury excitation. In that case, a suitable combination for producing white is a vacuum such as BAM and Y (P, VO) 4: Eu. What is necessary is just to select suitably what can obtain the light emission by an ultraviolet-ray.

On the other hand, when the phosphor of the present invention is used for a lamp used for image display, such as CCFL, deep green can be expressed as compared with a conventional LAP phosphor. A lamp is preferred. As a result, for example, a forest can be expressed as a more realistic green compared to the slightly yellowish green of conventional LAP. In this case, as the phosphor to be combined, a phosphor used in combination with Eu and Mn co-activated BAM for CCFL can be suitably used. For example, as a blue phosphor, a BAM phosphor having a y value smaller than 0.070, Alternatively, SCA or the like whose y value is smaller than 0.040 is preferably used, and Y2O3: Eu or Y (P, VO) 4: Eu is preferably used as the red phosphor, and YVO4 is particularly preferably used. : Eu. The phosphor of the present invention can be used by being incorporated in a backlight unit for a liquid crystal display device, and a wide color reproduction range can be obtained as a liquid crystal display device by using the phosphor of the present invention. In this case, from the viewpoint of widening the color reproduction range, a phosphor suitable for use in combination with the aluminate phosphor according to the first embodiment of the present invention is Eu-activated BAM phosphor or An SCA phosphor having a y value of 0.04 or less, and red is preferably a YOX or VYO4 phosphor.
Moreover, it can be used also as a fluorescent substance for LED by selecting the excitation wavelength suitably.

(Second embodiment of the present invention)
Aluminate phosphors suitable for the second embodiment of the present invention have the general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( where In the formula, x, y, z, and n are each represented by 0 <x <1, 0.6 ≦ y ≦ 1.8, 0 ≦ z ≦ 1, and 7 ≦ n. It is an aluminate phosphor.
It should be noted that the aluminate phosphor according to the second embodiment of the present invention may contain other elements in the composition thereof within a range not greatly excluding the effects of the present invention. For Mn and Mn, as well as the aluminate phosphor according to the first embodiment, Mg and Mn are not significantly affected by the effect of the aluminate phosphor according to the second embodiment of the present invention. Even if a small amount is substituted by a divalent metal such as Sr or Ba having a close ionic radius, Ce may be substituted by a small amount of Y, Gd, La, etc. A part of Al may be replaced by Ga and / or Sc.

The aluminate phosphor suitable for the second embodiment of the present invention has a stoichiometric composition of the conventional CAT: Mn phosphor << (total mole of (Ce + Tb): ratio of the total mole of (Mg + Mn)] Compared with the composition which is 1: 1 >>, depending on the luminance of the green light emission, the desired chromaticity, etc., (the total mole of Ce + Tb) :( the total mole of Mg + Mn) is from 2: 0.6 to 1.8 It has compositional characteristics in shifting.

The stoichiometric composition of the conventional CAT: Mn phosphor is that x in the general formula is an arbitrary number, the y value is 2, the z value is 0 <z ≦ 1, and the n value is 11. .
In the general formula, x (the ratio of Ce substituting Tb in the phosphor) may be appropriately selected within the range of 0 <x <1, but in order to obtain a phosphor with higher luminance, 0.5 ≦ x ≦ 0.9 is preferable.
If y in the general formula (ratio of (Mg + Mn) to the total of Ce ₂ O ₃ and Tb ₂ O ₃ in the phosphor) is less than 0.6, it is difficult to obtain sufficient light emission. On the other hand, if it exceeds 1.8, it will approach the conventional stoichiometric composition, and an improvement in light emission luminance cannot be achieved. Preferred ranges of the y value are 0.8 ≦ x and x ≦ 1.6, and more preferably 1.1 ≦ y and y ≦ 1.6.

Z in the general formula (ratio of Mn in Mg + Mn in the phosphor) may be appropriately selected so that desired chromaticity and luminance can be obtained within the range of 0 ≦ z ≦ 1, but the chromaticity point and luminance From the viewpoint, 0 ≦ z ≦ 0.2 is preferable. Most preferably, z = 0. When the phosphor does not contain z = 0, that is, does not contain Mn, the selection range of the chromaticity point is narrow. However, for example, the chromaticity can be appropriately mixed with the phosphor according to the first embodiment of the present invention. The point can be adjusted.
In the general formula, n (the ratio of Al ₂ O ₃ to the total of Ce ₂ O ₃ and Tb ₂ O ₃ in the phosphor) is 7 or more. As described above, in the phosphor of the present invention, the amount of Al ₂ O ₃ can be increased. On the other hand, if the n value is less than 7, the luminance characteristics are deteriorated, which is not preferable.
An n value of 11 or more is preferable because the shape of the crystal is rounded and it is easy to improve the film quality of the fluorescent film when it is applied. On the other hand, if it exceeds 20, the luminance starts to decrease. In terms of luminance, the n value is more preferably 11 ≦ n ≦ 20.

Similarly to the phosphor of the first embodiment, the aluminate phosphor of the second embodiment of the present invention is not particularly limited as long as the method usually used for producing the phosphor is used. Preferably, the Ce compound, the Tb compound, the Mg compound, the Mn compound, and the Al compound are used in the aluminate fluorescence in which the stoichiometric composition ratio of Ce, Tb, Mg, Mn, and Al is related to the second embodiment. It may be mixed and fired so as to match the composition ratio of the body. More preferably, (i) a cerium oxide, a cerium carbonate, a cerium nitrate, a Ce compound that can be converted into an oxide of cerium (Ce) by heating, (ii) terbium oxide, or terbium carbonate, terbium nitrate, terbium chloride, etc. Tb compound that can be changed to oxide of terbium (Tb) by heating, (iii) Mg compound that can be changed to oxide of magnesium (Mg) by heating such as magnesium oxide, or magnesium carbonate, and (iv) Aluminum oxide, or sulfuric acid An Al compound that can be converted into an oxide of aluminum (Al) by heating, such as aluminum, has a stoichiometric composition formula: (Ce _x Tb _1-x ) ₂ O ₃ .y (Mg _1-z Mn _z ) O · nAl ₂ O ₃ (where in the formula, x, y, z and n respectively, 0 ≦ x < , Weight ratio to form 0.6 ≦ y ≦ 1.8,0 <a satisfying number of z ≦ 1,7 ≦ n), it may be fired.

The method for producing an aluminate phosphor according to the second embodiment of the present invention can be performed, for example, by the following procedure.
(1) A predetermined amount of the raw materials as described above are weighed and sufficiently mixed by a mixing means using a ball mill, a V-type mixer or the like.
(2) The obtained mixture is filled in a heat-resistant container such as an alumina crucible and fired at 1400 to 1600 ° C. in a reducing atmosphere for 10 to 26 hours in a high temperature furnace including the time required for raising and lowering the furnace temperature.
(3) The resulting fired product is subjected to the same dispersion, washing, and drying treatments as in the post-processing step applied during normal phosphor production.
In the present invention, as in the case of obtaining a known aluminate phosphor in a mixture of phosphor raw material compounds subjected to firing, a fluoride such as aluminum fluoride or boric acid or boron oxide is used for promoting the reaction. Etc. may be added as a flux.

The particle diameter of the aluminate phosphor of the second embodiment of the present invention is not particularly limited, but when applied to the fluorescent film of the fluorescent lamp or the cold cathode fluorescent lamp of the present invention, From the viewpoint of uniformity, the FSSS particle size may be arbitrarily selected from the range of about 1 to 20, preferably 2 to 8.
The fluorescent lamp and cold cathode fluorescent lamp of the present invention are the same as the conventional cold cathode fluorescent lamp (of course, the so-called EEFL of the external electrode type), except that the thus obtained aluminate phosphor of the present invention is used as a fluorescent film. Manufactured).

That is, the aluminate phosphor according to the second embodiment of the present invention, together with phosphors of other colors as necessary, for example, low melting point glass powder, fine metal oxide, fine metal borate or phosphate, etc. A phosphor coating slurry is prepared by suspending in water or an organic solvent such as butyl acetate or isopropyl alcohol together with the binder of the above, and this is applied to the inner wall of the glass tube and dried to form a phosphor film. After baking, mercury sealing, decompression, sealing, and electrode mounting may be performed.

The aluminate phosphor according to the second embodiment of the present invention and the fluorescent lamp using the same are preferably used for general illumination, and the color reproduction range is a conventional cold cathode fluorescent lamp (usually blue). Compared with BAM phosphor, LAP phosphor as green, and YOX (yttrium oxide) phosphor as red), a wide range can be reproduced. Therefore, it can be used by being incorporated in a backlight unit for a liquid crystal display device, and a wide color reproduction range can be obtained as a liquid crystal display device by using the phosphor of the present invention.
Moreover, it can be used also as a fluorescent substance for LED by selecting the excitation wavelength suitably.

(Third embodiment of the present invention)
The third embodiment of the present invention was made based on the fact that among the compositions included in the second embodiment of the present invention, there is a composition having extremely excellent characteristics in 1/10 afterglow time. Since this effect cannot be obtained with a phosphor having a normal stoichiometric composition, it will be described in detail as a third embodiment.
The aluminate phosphor according to the third aspect of the present invention is a phosphor composed of at least Ce, Tb, Mg, Al and O, and has a 1/10 afterglow time of 6.4 ms or less. It is an aluminate phosphor.
The term “consisting of” used in the specification of the present invention is not limited to the portion of the third embodiment, but includes those containing other substances as long as the effects of the present invention are not significantly impaired.
If the 1/10 afterglow time is longer than 6.4 ms, it is not significantly different from conventional products, and is inappropriate for LCD backlights that require short afterglow time, preferably 6.0 ms or less, more preferably Is 5.7 ms or less.

The feature of the aluminate phosphor according to the third embodiment of the present invention is a phosphor composed of at least Ce, Tb, Mg, Al, and O, having a 1/10 afterglow time of 6.4 ms or less. The composition is not particularly limited. Preferably the general formula _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3 ( where in the formula, x, y, z and n respectively, 0.68 ≦ x ≦ 0.95, 0.6 ≦ y ≦ 1.8, z = 0, and 7 ≦ n.

In addition, the phosphor represented by the above general formula may contain other elements in the composition in a range not greatly excluding the effect of the present invention. For specific examples, regarding Mg and Mn, As in the first aspect, there is no problem even if a small amount is substituted by a divalent metal such as Sr or Ba, which has an ionic radius close to that of Mg or Mn, as long as the effect of the present invention is not significantly impaired. Similarly, Ce may be replaced with a small amount of Y, Gd, La, etc., and a part of Al may be replaced with Ga and / or Sc.

The aluminate phosphor represented by the above general formula has Ce / Tb = 2.0 which is a suitable composition of the conventional CAT phosphor or Mg / (Ce + Tb) = 1.0 which is also a stoichiometric composition. The ratio of Tb to Ce (in the above formula, x / (1-x) ratio) or the ratio of Mg to (Ce + Tb) depending on the luminance of green light emission, the desired afterglow time, etc. In the above formula, the y value) is shifted.

As described above, the aluminate phosphor according to the third embodiment of the present invention has a composition or stoichiometric composition in which the content ratio of each metal element constituting the phosphor is suitable for the conventional CAT phosphor. This deviation (non-stoichiometry) causes changes in the crystal structure and optical properties (afterglow characteristics) of the phosphor, and it is assumed that the phosphor can have excellent characteristics. . The stoichiometric composition of the conventional CAT phosphor is that x in the general formula is an arbitrary number, the y value is 2, the z value is 0, and the n value is 11.

When 1-x in the general formula (the ratio of Tb substituting Ce in the phosphor) becomes small, the luminance of the phosphor tends to decrease, but the rise time of the luminance is shortened by shortening the afterglow time. Therefore, it works favorably on the brightness. However, if 1-x is less than 0.05, that is, if x exceeds 0.95, the decrease in Tb emission (green emission) is too low, leading to a decrease in the brightness of the entire phosphor.

On the other hand, if the 1-x value is 0.32 or more, that is, x <0.68, the conventional suitable composition is approached and the afterglow time cannot be shortened. Therefore, the preferable range of the x value is 0.68 ≦ x ≦ 0.95, and the more preferable range of the x value is 0.7 ≦ x ≦ 0.85, more preferably considering the balance with the luminance. Is 0.7 ≦ x ≦ 0.75, and if the afterglow time characteristic is more important, 0.75 ≦ x ≦ 0.85.

By reducing the amount of Tb with respect to Ce in the phosphor (that is, the x value in the general formula is 0.68 or more), the afterglow time can be shortened, and x = 0. Up to about 95, it can maintain almost the same brightness as the conventional one. Further, since the ratio of the relatively expensive Tb to the base component is reduced, the manufacturing cost can be reduced.

If the y value in the general formula (ratio of MgO to the total of Ce ₂ O ₃ and Tb ₂ O ₃ in the phosphor) is less than 0.6, the afterglow time becomes shorter but sufficient light emission is obtained. It's hard to be done. On the other hand, if it exceeds 1.8, the luminance tends to decrease. A preferable range of the y value is 0.6 ≦ y ≦ 1.8, and more preferably 0.8 ≦ y ≦ 1.6.
The afterglow time can be significantly shortened by reducing the amount of Tb for Ce in the phosphor and reducing the amount of Mg for (Ce + Tb).
The n value in the general formula (the ratio of Al ₂ O ₃ to the total of Ce ₂ O ₃ and Tb ₂ O ₃ in the phosphor) is 7 or more. If the n value is less than 7, the luminance characteristics deteriorate, which is not preferable.

Further, when the n value is 11 or more, the crystal shape is rounded, and it is easy to improve the film quality of the fluorescent film when applied. On the other hand, when it exceeds 30, the luminance starts to decrease. In terms of emission luminance, the lower limit value more preferable as the n value is 11 or more, and the preferable upper limit value is 30 or less, and more preferably 20 or less.
Of course, the preferable 1/10 afterglow time of the phosphor represented by this general formula is 6.4 ms or less.
When the 1/10 afterglow time is longer than 6.4 ms, it is unsuitable for LCD backlights that require short afterglow, preferably 6.0 ms or less, and more preferably 5.7 ms or less.

Similarly to the phosphor of the first embodiment, the aluminate phosphor of the third embodiment of the present invention is not particularly limited as long as the method usually used for producing the phosphor is used. Preferably, the Ce compound, the Tb compound, the Mg compound, and the Al compound are stoichiometrically mixed with the composition ratio of the aluminate phosphor in which the composition ratio of Ce, Tb, Mg, and Al is related to the third embodiment. What is necessary is just to mix and bake so that it may correspond. More preferably, (i) a cerium oxide, a cerium carbonate, a cerium nitrate, a Ce compound that can be converted into an oxide of cerium (Ce) by heating, (ii) terbium oxide, or terbium carbonate, terbium nitrate, terbium chloride, etc. Tb compound that can be changed to oxide of terbium (Tb) by heating, (iii) Mg compound that can be changed to oxide of magnesium (Mg) by heating such as magnesium oxide, or magnesium carbonate, and (iv) Aluminum oxide, or sulfuric acid An Al compound that can be converted into an oxide of aluminum (Al) by heating, such as aluminum, has a stoichiometric composition formula: (Ce _x Tb _1-x ) ₂ O ₃ .y (Mg _1-z Mn _z ) O · nAl ₂ O ₃ (where in the formula, x, y, z and n respectively, 0.68 x ≦ 0.95,0.6 ≦ y ≦ 1.8, z = 0,7 is a satisfying number of ≦ n) and weight ratio to form, may be fired.

The method for manufacturing the aluminate phosphor according to the third embodiment of the present invention is the same as the method for manufacturing the aluminate phosphor according to the first and second embodiments of the present invention. Can be done in a simple procedure.
(1) A predetermined amount of the raw materials as described above are weighed and mixed sufficiently by mixing means using a ball mill, a V-type mixer or the like.
(2) The obtained mixture is filled in a heat-resistant container such as an alumina crucible and fired at 1400 to 1600 ° C. in a reducing atmosphere for 10 to 26 hours in a high temperature furnace including the time required for raising and lowering the furnace temperature.
(3) The obtained fired product is subjected to the same dispersion, washing, and drying treatments as in the post-treatment step applied during normal phosphor production.
In the present invention, as in the case of obtaining a known aluminate phosphor in a mixture of phosphor raw material compounds subjected to firing, a fluoride such as aluminum fluoride or boric acid or boron oxide is used for promoting the reaction. Etc. may be added as a flux.

The particle size of the aluminate phosphor of the third embodiment of the present invention is not particularly limited, but when applied to the fluorescent film of the fluorescent lamp of the present invention or the cold cathode fluorescent lamp, the handling and color uniformity are not limited. From the viewpoint of properties, the FSSS particle size may be arbitrarily selected from the range of about 1 to 20, preferably 2 to 8.
The fluorescent lamp or cold cathode fluorescent lamp of the present invention is produced in the same manner as conventional fluorescent lamps and cold cathode fluorescent lamps, except that the thus obtained aluminate phosphor of the present invention is used as a fluorescent film. The

That is, the aluminate phosphor of the present invention is combined with other color phosphors as necessary, for example, a low melting point glass powder, a particulate metal oxide, or a binder such as a particulate metal borate or phosphate with water or A phosphor-coated slurry is prepared by suspending in an organic solvent such as butyl acetate or isopropyl alcohol. The obtained slurry is applied to the inner wall of the glass tube and dried with warm air to form a fluorescent film, which is baked and then sealed with mercury, decompressed, sealed, and attached with an electrode.

In the cold cathode fluorescent lamp of the present invention, the aluminate phosphor according to the third embodiment of the present invention described so far is used as the green phosphor, and the 1/10 afterglow time is 1.0 ms or less. It is preferable to use as the phosphor film a mixed phosphor formed by mixing a blue phosphor of 1 and a red phosphor having a 1/10 afterglow time of 3.0 ms or less.
Examples of blue phosphors having a 1/10 afterglow time of 1.0 ms or less include Eu-activated strontium / calcium apatite phosphors (hereinafter also referred to as SCA phosphors), BAM phosphors, etc. Among them, SCA phosphors Can be suitably used.
Examples of red phosphors having a 1/10 afterglow time of 3.0 ms or less include YOX phosphors and Eu-activated yttrium vanadate phosphors (hereinafter also referred to as YVO phosphors). It can be used suitably.

Since the aluminate phosphor of the third embodiment of the present invention is characterized by a short 1/10 afterglow time, by appropriately selecting a multicolor phosphor to be combined therewith as described above Thus, a fluorescent lamp having a short afterglow time can be produced, and a backlight unit having a short afterglow time or an intermittent lighting using the fluorescent lamp can be used to obtain a liquid crystal display device having excellent moving image characteristics.

The phosphor of the present invention has a phosphor surface that is coated with a coating material composed of an inorganic compound or an organic compound for the purpose of suppressing deterioration of luminance over time and improving life characteristics. It can also be coated.
The method of the coating treatment is not particularly limited. For example, the coating material formed into fine particles is mixed with the phosphor to be coated and dried to adhere, or the coating material is deposited on the surface of the phosphor to be coated. Such as a method of adjusting pH and the like, a method of adsorbing on the surface of a phosphor to be coated using an electric potential, or a method of coating by separately mixing a substance serving as a binder. It can be arbitrarily selected according to the characteristics.

Specific examples of the coating material include various oxides such as magnesium oxide, lanthanum oxide and yttrium oxide; carbonates such as alkaline earth metal carbonates and rare earth metal carbonates; hydroxides such as yttrium hydroxide and the like. Can be mentioned. Among them, the coating with rare earth metal carbonate described in Japanese Patent No. 4199530 is preferable in the case of using for lamps because the effect of improving the life is great.
The rare earth metal carbonate is preferably yttrium carbonate, lanthanum carbonate or the like, and the coating amount is preferably 0.05 to 5% by weight, preferably 0.1 to 1.0% by weight based on the phosphor. Is more preferable.

EXAMPLES Hereinafter, although this invention is demonstrated in detail using an Example, this invention is not limited and limited to an Example, unless the summary is exceeded.
(Example corresponding to the first embodiment of the present invention)
[Examination of y value and z value 1: Constant ratio change of Mg amount when Mn and Al are constant]
When the amount of manganese and aluminum was fixed, the amount of magnesium was changed and the improvement of light emission luminance was examined.

Example 5
· _Ce 2 _O 3: 1.00mol
・ MgCO ₃ : 0.47 mol
・ MnO ₂ : 0.42 mol
· _Al 2 _{O 3} (alpha type): 12.94mol
・ AlF ₃ : 0.02 mol
After sufficiently mixing the above raw materials, the crucible is filled, and then a lump of graphite is placed on the phosphor raw material. The lid is covered, and the temperature is increased and lowered at a maximum temperature of 1550 ° C in a nitrogen atmosphere containing water vapor. And baked for 24 hours.

Next, the fired powder is subjected to dispersion, washing, drying, and sieving treatment, and the composition formula is Ce ₂ O ₃ .0.42MnO · 0.47MgO · 12.9Al ₂ O ₃ << ie Ce ₂ O ₃ · 0. A Mn ²⁺ activated aluminate phosphor represented by .89 (Mn _0.47 , Mg _0.53 ) O · 12.9Al ₂ O ₃ was obtained. AlF ₃ is a flux generally used for manufacturing phosphors.
Table 2 shows the chromaticity and luminance of light emission of the obtained phosphor. In Table 2, the Al ₂ O ₃ column represents the n value, the Mg + Mn column represents the y value, and the Mn / (Mg + Mn) column represents the z value.
As a method for measuring color luminance, a color luminance meter (manufactured by Konica Minolta Co., Ltd .: CS200) is used. ) Was set to 100, and the luminance was measured.

Examples 1 to 4, 6 to 12, and Comparative Examples 1 to 5
Mn ²⁺ activated aluminate phosphors of Examples 1 to 4, 6 to 12 and Comparative Examples 1 to 5 were obtained in the same manner as Example 5 except that the composition shown in Table 2 was used.
Table 2 also shows the chromaticity and luminance of each phosphor obtained. Further, the luminance accompanying the change of the y value based on the results of Table 2 is shown in the graph of FIG.
[Examination of y value and z value 2: Constant ratio change of Mn amount when Mg and Al are constant]
When the amount of magnesium and aluminum was fixed, the amount of manganese was changed and the improvement of the light emission luminance was examined.

Examples 14-20
Mn ²⁺ activated aluminate phosphors of Examples 14 to 20 were obtained in the same manner as in Example 5 except that the composition shown in Table 2 was used.
Table 2 also shows the chromaticity and luminance of each phosphor obtained.
[Examination of n value: Constant ratio change of Al amount when Mn and Mg are constant]
When the amount of manganese and magnesium was fixed, the amount of aluminum was changed and the improvement of light emission luminance was examined.

Examples 21-29
Mn ²⁺ activated aluminate phosphors of Examples 21 to 29 were obtained in the same manner as in Example 5 except that the composition shown in Table 2 was used.
Table 2 also shows the chromaticity, luminance, and average particle diameter measured by the FSSS method of each phosphor obtained.
Further, based on the results in Table 2, the luminance accompanying the change in the Al content is shown in the graph of FIG. In FIG. 4, the horizontal axis represents the n value (alumina amount in the phosphor).
Further, for Examples 22 to 28, the particle diameter accompanying the change in the Al content is shown in the graph of FIG. 5 based on the results shown in Table 2. In FIG. 5, the horizontal axis represents the amount of Al (mol) in the phosphor.

[Examination of Mg content]
Example 13
A Mn ²⁺ activated aluminate phosphor of Example 13 was obtained in the same manner as in Example 5 except that the composition shown in Table 2 was used.
Table 2 shows the chromaticity and luminance of the obtained phosphor.
As described above, all of Examples 1 to 29 exhibited green light emission with higher luminance than Comparative Examples 1 to 5.
Further, from the results of Examples 22 to 28, it was found that when the amount of Al ₂ O ₃ is increased, the average particle size tends to decrease.

(Example corresponding to the second embodiment of the present invention)
[CAT phosphor]
Examples 30 to 37, 70 and Comparative Examples 6 and 7
After sufficiently mixing six raw materials (CeO ₂ , Tb ₄ O ₇ , MgCO ₃ , Al ₂ O ₃ (alpha type), H ₃ BO ₃ , and AlF ₃ ) so as to have the compositions shown in Table 3, respectively. Then, the crucible was filled, and a graphite lump was placed on the phosphor material, and the lid was covered and fired in a nitrogen atmosphere containing water vapor at a maximum temperature of 1550 ° C. for 24 hours including heating and cooling. H ₃ BO ₃ and AlF ₃ in the raw material are fluxes generally used for the production of phosphors.
The fired powder was then dispersed, washed, dried, and sieved to obtain Tb-activated aluminate phosphors of Examples 30 to 37 and 70 and Comparative Examples 6 and 7. The composition was confirmed by ICP.
Table 3 shows the emission color (chromaticity), relative luminance, and average particle diameter measured by the FSSS method (Fischer sub-sieve sizer method) of each phosphor obtained.
A chromaticity meter (trade name “CS200” manufactured by Konica Minolta Co., Ltd.) was used for the measurement of chromaticity. As for the emission luminance, a terbium-activated lanthanum phosphate phosphor for a cold cathode fluorescent lamp (trade name “LP-G2 manufactured by Kasei Optonics Co., Ltd.), which was measured as a standard product in the same manner as the phosphor of each example, was used. The relative value when the luminance of “)” is 100 is shown.

Further, based on the results shown in Table 3 (Examples 30 to 37, 70 and Comparative Examples 6 and 7), the n value (number of moles of Al ₂ O ₃ relative to the total moles of Ce + Tb) was 11.0 (× mark). ) And 13.0 (marked with ●), FIG. 6 shows changes in emission luminance of each phosphor accompanying changes in the y value (Mg amount relative to the total moles of (Ce + Tb)).
Although not shown, in the phosphor of the present invention, even when the n value is 11.0 or a value other than 13.0, the correlation between the y value and the emission luminance is almost It was confirmed that the correlation was similar to that shown in FIG.

FIG. 7 is a graph illustrating emission spectra when the phosphors of Examples 30 to 34 and Comparative Example 6 are excited with ultraviolet light having a wavelength of 254 nm. FIG. 8 shows the vicinity of the main peak of the spectrum of FIG. An enlarged spectrum of the wavelength region is shown.
7 and 8, the emission spectrum of the phosphor of the example has a larger emission intensity of 545 nm than the emission intensity of 542 nm, and the subpeak emission intensity in the vicinity of 490 nm, 580 nm, and 620 nm. Since no change is observed, relatively unnecessary light emission is reduced, and when used as a phosphor for a light emitting display, an improvement in crosstalk is expected. This is because the sub-peak of 490 nm close to 450 nm, which is blue light emission, cannot be completely cut by the blue filter, and the blue color purity deteriorates. Similarly, emission at 580 nm deteriorates red color purity. The phosphor of the present invention does not change the absolute intensity of these sub-peaks, but the main emission (sum of 542 nm and 545 nm) used as green has increased intensity, so the sub-peak is relatively low. This is because the same effect is obtained.

[CAT: Mn phosphor]
Example 38, Example 39, Comparative Example 8, and Comparative Example 9
Seven kinds of raw materials (CeO ₂ , Tb ₄ O ₇ , MgCO ₃ , MnCO ₃ , Al ₂ O ₃ (alpha type), H ₃ BO ₃ , and AlF ₃ ) are sufficiently provided to have the compositions shown in Table 3, respectively. After mixing, firing, dispersion, washing, drying, and sieving were performed in the same manner as in Examples 30 to 37 and 70 and Comparative Examples 6 and 7, and Tb of Examples 38 and 39 and Comparative Examples 8 and 9 were used. ^{A 2 +} · Mn ²⁺ co-activated aluminate phosphor was obtained. The composition was confirmed by ICP.
Table 3 shows the emission color (chromaticity), relative luminance, and average particle diameter measured by the FSSS method (Fischer sub-sieve sizer method) of the obtained phosphor.
The measuring methods of chromaticity, relative luminance, and particle diameter are the same as in Examples 30 to 37 and 70 and Comparative Examples 6 and 7.

FIG. 9 is a graph illustrating emission spectra when the phosphors of Example 38, Example 39, Comparative Example 8, and Comparative Example 9 are excited with ultraviolet light having a wavelength of 254 nm.
As can be seen from FIG. 9, in the phosphors of Examples (38 and 39), as in the case of the CAT phosphor, the emission intensity of 545 nm with respect to 542 nm is improved and the emission intensity of Mn near 517 nm is also improved. I understand that.
In addition, as shown in FIG. 10, the aluminate phosphors of the present invention (Examples 38 and 39) have an absorption of mercury emission as compared with the stoichiometric compositions (Comparative Examples 8 and 9). It has been improved.
From FIG. 10, the aluminate phosphor of the present invention shifted in the direction of decreasing y from the stoichiometric composition (y = 2.0) has a wavelength of 172 nm as compared with the conventional phosphor having the stoichiometric composition. It can be seen that the excitation intensity increases both in the wavelength range of the VUV and in the wavelength range of the mercury line with a wavelength of 254 nm. In particular, the increase in excitation intensity is preferably from 140 nm to 300 nm, more preferably from 180 nm to 300 nm.

(Example corresponding to the third embodiment of the present invention)
[Phosphor]
Examples 40 to 55, 71, 72 and Comparative Examples 12, 14, 15
After sufficiently mixing the six raw materials (CeO ₂ , Tb ₄ O ₇ , MgCO ₃ , Al ₂ O ₃ (alpha type), H ₃ BO ₃ , and AlF ₃ ) so as to have the compositions shown in Table 4, respectively. Then, the crucible was filled, and a graphite lump was placed on the phosphor material, and the lid was covered and fired in a nitrogen atmosphere containing water vapor at a maximum temperature of 1550 ° C. for 24 hours including heating and cooling. H ₃ BO ₃ and AlF ₃ in the raw material are fluxes generally used for the production of phosphors. The numerical values in the columns 1-x, x, y, and n in Table 4 are the values in the general formula (Ce _1-x Tb _x ) ₂ O ₃ .yMgO.nAl ₂ O ₃ because there is no Mn. (Omitted including z) The values of 1-x, x, y, and n are represented respectively, and each numerical value in the Mg column is the number of moles of Mg in the phosphor.
Next, the fired powder was dispersed, washed, dried, and sieved to obtain Tb-activated aluminate phosphors of Examples 40 to 55, 71, and 72 and Comparative Examples 12, 14, and 15. The composition was confirmed by ICP. Examples 40 to 55, 71 and 72 and Comparative Examples 12, 14, and 15 are mainly intended to show the relationship between the 1/10 afterglow time when the amount of Tb is changed and the relative luminance.

The emission color (chromaticity), relative luminance, 1/10 afterglow time, and average particle size of each phosphor obtained were evaluated by the following evaluation methods. The results are shown in Table 4. The average particle size was measured only for the phosphors of Examples 40 to 50.
(A) Chromaticity: It was measured using a color luminance meter (trade name “CS200” manufactured by Konica Minolta).
(B) Relative luminance: Commercially available terbium-activated lanthanum phosphate phosphor for cold cathode fluorescent lamp (trade name “LP- manufactured by Kasei Optonics Co., Ltd.), measured in the same manner as the phosphor of each example. The value is shown as a relative value when the light emission luminance of G2 ″) is 100.
(C) Average particle diameter: Measured according to the FSSS method (Fischer sub-sieve sizer method).
(D) 1/10 afterglow time: Measured in a phosphorescence measurement mode (phosphorescent short life) using a trade name “F-4500 type spectrofluorometer” manufactured by Hitachi, Ltd. The time (ms) until the emission intensity at the peak wavelength near 540 nm at the start of the measurement was attenuated to 1/10 after the irradiation of the ultraviolet light was emitted after being irradiated with the ultraviolet light having a wavelength of 254 nm was obtained. .

Based on the results shown in Table 4 (Examples 40 to 55, 71, 72 and Comparative Examples 12, 14, 15), a phosphor having a y value of 1.3 and an n value of 13.0, and a y value of 2 FIG. 11 shows a change in 1/10 afterglow time of each phosphor with a change in 1-x value (Tb amount with respect to Ce amount) for a phosphor having an 0.0 value and an n value of 13.0.

In addition, FIG. 12 shows changes in luminance of each phosphor accompanying changes in the x value. Comparative Example 14 is a stoichiometric composition and an accurate composition of known literature, y = 2, and Ce / Ce + Tb = 2.
Although not shown, in the phosphor of the present invention, even when the y value is 1.3 and the n value is other than 13.0, the correlation between the x value and the afterglow time is as follows: It is confirmed that the relationship is almost similar to the correlation shown in FIG. On the other hand, as apparent from FIG. 11, when the y value is 2.0 and the n value is 13.0, that is, when the amount of cerium and terbium is changed while maintaining the stoichiometric composition, the 1/10 afterglow time The effect of shortening is relatively small. On the other hand, FIG. 12 shows that the luminance tends to be higher when the y value is lower, but the correlation between the luminance and x is not significantly affected by the y value. It can be seen that the luminance decreases rapidly when x is 0.85 or more.

Examples 56 to 61, 80 and Comparative Examples 16 to 19
In the same manner as in Example 40, phosphors of Examples 56 to 61 and 80 and Comparative Examples 16 to 19 were produced with the composition ratios shown in Table 5. The results are shown in Table 5 and FIGS. 13 and 14 together with the results of Example 47 (the numerical values in Table 5 are the same as those in Table 4). Here, the x value is fixed to x = 0.67 which is the recommended composition, and the y value is changed. The average particle size was measured only for the phosphors of Examples 56 to 61 and 80 and Comparative Examples 18 and 19.
From the data of 1/10 afterglow time in FIG. 13, it can be seen that when y becomes smaller than the stoichiometric composition y = 2, the 1/10 afterglow time rapidly decreases. On the other hand, from the viewpoint of luminance, it can be seen that y is preferably 0.6 or more as shown in FIG.

Examples 62 to 65 and Comparative Example 20
In the same manner as in Example 40, phosphors of Examples 62 to 65 and Comparative Example 20 were manufactured at the composition ratio shown in Table 6. The results are shown in Table 6, FIG. 15 and FIG. 16 (the numerical values in Table 6 are the same as in Table 4). Here, the x value is fixed to 1-x = 0.33 which is the recommended composition, the y value is fixed to 1.3, and the n value is changed.
From the data of 1/10 afterglow time in FIG. 15, it can be seen that when n is smaller than 7, the 1/10 afterglow time is rapidly increased. On the other hand, n is more preferably 11 or more from the point of brightness.

[White fluorescent lamp]
Example 66
As the green phosphor, the phosphor described in Example 45 was used. The blue phosphor “LP-B4” (BAM phosphor) manufactured by Kasei Optonics Co., Ltd. and the red phosphor “LP-RE1” manufactured by Kasei Optonics Co., Ltd. ( And a white cold cathode lamp having a chromaticity point of (x / y = 0.270 / 0.240).
Comparative Example 22
A white cold cathode lamp having a chromaticity point of (x / y = 0.270 / 0.240) as in Example 66, except that the phosphor described in Comparative Example 6 was used as the green phosphor. Was made.
Comparative Example 23
Similar to Example 66, except that the green phosphor “LP-G2” (LAP phosphor) manufactured by Kasei Optonix was used as the green phosphor, the chromaticity point was (x / y = 0.270 / 0.240) was produced.
When the luminances of the lamps of Example 66, Comparative Example 22, and Comparative Example 23 were measured, when the luminance of the lamp of Comparative Example 23 was 100, all of the lamps of Comparative Example 22 and Example 66 were 99. Brightness. From this result, it can be seen that the lamp luminance of the aluminate phosphor having a short afterglow time of the present invention has a lamp luminance equivalent to that of the conventional product and is practical.

The aluminate phosphor of the present invention exhibits a brighter green light emission than the conventionally known Mn-activated cerium-magnesium-aluminate phosphor, and more visible light than the near ultraviolet region compared to the conventional product. The emission intensity in the region is high and the absorption of mercury rays is excellent.
Further, the aluminate phosphor of the present invention has a brightness equivalent to or higher than that of conventionally known Tb-activated cerium / magnesium / aluminate phosphors and Tb / Mn co-activated cerium / magnesium / aluminate phosphors. It emits green light.
Furthermore, the aluminate phosphor of the present invention exhibits a green emission while having substantially the same brightness as a conventionally known Tb-activated cerium-magnesium-aluminate phosphor, and has a significant afterglow time. Is short.
The aluminate phosphor of the present invention having the above characteristics includes a cold cathode fluorescent lamp, a rare gas lamp, a mercury lamp, a backlight unit, a liquid crystal display device, a plasma display, an LED, and the like utilizing excitation in a vacuum ultraviolet region or an ultraviolet region. It can be suitably used in a wide range of fields.
Note that Japanese Patent Application No. 2008-190855 filed on July 24, 2008, Japanese Patent Application No. 2008-270155 filed on October 20, 2008, and Japanese Patent Application filed on March 13, 2009. The entire contents of the specification, claims, drawings and abstract of patent application 2009-061087 are hereby incorporated herein by reference as the disclosure of the specification of the present invention.

Claims (24)

1. General formula;
   _{(Ce x Tb 1-x)} 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3
   (However, in the formula, x, y, z and n are numbers satisfying the conditions of 0.6 ≦ y ≦ 1.8, 0 ≦ z ≦ 1, and 7 ≦ n, respectively, when 0 <x <1. , X = 1, 0.2 ≦ y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n. .
2. The aluminate phosphor according to claim 1, wherein x = 1 and 0.3 ≦ y ≦ 1.2 in the general formula.
3. 3. The aluminate phosphor according to claim 2, wherein x = 1 and 0.7 ≦ y ≦ 1.2 in the general formula.
4. 4. The aluminate phosphor according to claim 2, wherein in the general formula, n is 12 ≦ n ≦ 40.
5. A phosphor composed of at least cerium (Ce), manganese (Mn), magnesium (Mg), aluminum (Al), and oxygen (O), and 350 nm with respect to the emission intensity at a wavelength of 518 nm when excited by ultraviolet light at a wavelength of 254 nm The aluminate phosphor characterized in that the ratio of the emission intensity is less than 15%.
6. The phosphor has the general _{formula; (Ce x Tb 1-x} ) 2 O 3 · y (Mg 1-z Mn z) O · nAl 2 O 3
   In the general formula, x, y, z, and n are numbers satisfying the conditions of x = 1, 0.2 ≦ y ≦ 1.8, 0.1 ≦ z ≦ 1, and 7 ≦ n, respectively. The aluminate phosphor according to claim 5, wherein the aluminate phosphor is provided.
7. The aluminate phosphor according to claim 1, wherein, in the general formula, x is 0 <x <1, and y is 0.8 ≦ y ≦ 1.6.
8. The aluminate phosphor according to claim 7, wherein x is 0.5 ≦ x ≦ 0.9 in the general formula.
9. The aluminate phosphor according to any one of claims 1 to 3, wherein in the general formula, n is 11≤n.
10. 10. The aluminate phosphor according to claim 7, wherein in the general formula, z is z = 0.
11. 2. The aluminate phosphor according to claim 1, wherein in the general formula, 0.68 ≦ x ≦ 0.95 and z = 0.
12. The aluminate phosphor according to claim 11, wherein 0.7 ≦ x ≦ 0.85 in the general formula.
13. A phosphor composed of at least cerium (Ce), terbium (Tb), magnesium (Mg), aluminum (Al), and oxygen (O), and having a 1/10 afterglow time of 6.4 ms or less. Aluminate phosphor.
14. The aluminate phosphor according to any one of claims 1 to 13, wherein the surface is coated with a coating substance.
15. 15. The aluminate phosphor according to claim 14, wherein the coating material is a rare earth metal carbonate.
16. The aluminate phosphor according to claim 15, wherein a coating amount of the rare earth metal carbonate is 0.05 to 5% by weight with respect to the phosphor.
17. The Ce, Tb compound, Mg compound, Mn compound, and Al compound have a stoichiometric composition formula for Ce, Tb, Mg, Mn, and Al, as defined in any one of claims 1 to 4 and 6 to 12. A method for producing an aluminate phosphor, comprising mixing and firing at a ratio described in the item.
18. Ce compound that can be changed to oxide of cerium (Ce) by heating, Tb compound that can be changed to oxide of terbium (Tb) by heating, Mg compound that can be changed to oxide of magnesium (Mg) by heating, Manganese (Mn by heating) The composition formula stoichiometrically with respect to Ce, Tb, Mg, Mn, and Al is an Mn compound that can be converted into an oxide of (A) and an Al compound that can be converted into an oxide of aluminum (Al) upon heating. A method for producing an aluminate phosphor, comprising mixing and firing at a ratio according to any one of 4 and 6 to 12.
19. A fluorescent lamp using the aluminate phosphor according to any one of claims 1 to 16.
20. The fluorescent lamp according to claim 19, wherein the fluorescent lamp is a cold cathode fluorescent lamp.
21. The aluminate phosphor according to any one of claims 1 to 16 as a green phosphor, the phosphor having a 1/10 afterglow time of 1.0 ms or less as a blue phosphor,
    A cold cathode fluorescent lamp characterized in that a phosphor having a 1/10 afterglow time of 3.0 ms or less is used as a red phosphor.
22. The blue phosphor is an Eu activated strontium / calcium apatite phosphor or an Eu activated barium / magnesium aluminate phosphor,
    The cold cathode fluorescent lamp according to claim 21, wherein the red phosphor is an Eu activated yttrium oxide phosphor or an Eu activated yttrium vanadate phosphor.
23. A backlight unit using the fluorescent lamp according to claim 19 or 20, or the cold cathode fluorescent lamp according to claim 21 or 22.
24. 25. A liquid crystal display device, wherein the backlight unit according to claim 23 is used and pseudo-impulse driving is performed.

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