JP2009249396A - Luminous white light emitting phosphor, fluorescent lamp, luminous display, and luminous molded product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a luminous white light emitting phosphor, which is excited by ultraviolet rays, exhibits high afterglow intensity after the excitation light is interrupted and can maintain light emission with good white color purity in particular, a fluorescent lamp, a luminous display, and a luminous molded product each using the phosphor. <P>SOLUTION: The luminous phosphor is produced by mixing or mutually sticking a first phosphor, which absorbs ultraviolet rays to emit long persistent light in a first wavelength area, and a second phosphor, which absorbs at least a part of light emission in the first wavelength area to emit light in a second wavelength area. In the phosphor, chromaticity points of light emission is within a rectangle surrounding by a point P (0.200, 0.200), a point Q (0.300, 0.400), a point R (0.400, 0.400) and a point S (0.300, 0.400) in the chromaticity coordinate, and intensity (I<SB>[10]</SB>) of afterglow after 10 minutes from interruption of irradiation, which is carried out for 20 minutes with illuminance of 200 lx by a fluorescent lamp of an ordinary light source D65, is 110 mcd/m<SP>2</SP>or more. The fluorescent lamp, the luminous display body, and the luminous molded product each using the phosphor are also provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a phosphor that absorbs ultraviolet rays in sunlight, ultraviolet rays such as fluorescent lamps, and exhibits long afterglow white light emission (hereinafter also referred to as phosphorescent white light-emitting phosphor), and fluorescence using the phosphor The present invention relates to luminous displays such as lamps, evacuation guidance signs, displays, and luminous molded articles.

In recent years, safe and appropriate evacuation guidance measures have been studied in the event of a sudden power failure in high-rise buildings, subways, homes, etc. in large cities due to earthquakes, etc. or in situations where there is a risk of tsunamis outdoors. As products, evacuation guidance signs using phosphorescent phosphors that emit light for a long time even during a power outage or at night, phosphorescent sheets and phosphorescent tapes that are affixed to stairs, handrails, and the like have come to be used.
In addition, phosphorescent phosphors are also used in fluorescent films of fluorescent lamps used in homes and offices, diffusion plates and cover sheets attached to fluorescent lamps, fluorescent lamp switches, and the like. In addition, phosphorescent phosphors have come to be used in a wide variety of forms such as plastic displays such as wall displays, toys and fishing gear, and glass, ceramics, and ceramics. In recent years, there has been a strong demand for the development of phosphorescent phosphors having higher luminance and emitting various emission colors.

By the way, as a phosphorescent phosphor for the above-mentioned uses, conventionally, a blue-emitting (Ca, Sr) S: Bi phosphor, a yellow-green emitting ZnS: Cu phosphor, and a red-emitting (Zn, Cd). Sulphide-based phosphors such as S: Cu phosphors are known.
However, the (Ca, Sr) S: Bi phosphor described above has extremely poor matrix stability and insufficient luminance and afterglow characteristics. In addition, (Zn, Cd) S: Cu is a toxic substance, and Cd occupies about half of the matrix, and neither brightness nor afterglow can be satisfied. Further, ZnS: Cu phosphors are inexpensive and have been used considerably, such as evacuation guidance signs and indoor nighttime displays, but the afterglow time that can be recognized with the naked eye is not so long as 1-2 hours, and the weather resistance is also poor.

In recent years, Sr—Mg—Si complex oxide phosphors (Patent Document 1) activated with Eu and Dy that emit blue light and SrAl ₂ O _{4 that} emits green light as novel phosphorescent phosphors with higher luminance: Eu,
Dy (Patent Document 2), Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy (Patent Document 3) emitting green-blue light, Sr ₂ SiO ₄ : Eu: Dy, SrAl ₂ Si ₂ O ₈ : Eu, Dy, Sr ₆ Al Sr—Al-based and Sr—Al—Si-based complex oxide phosphors activated with Eu and Dy such as ₁₈ Si ₂ O ₃₇ : Eu, Dy (Patent Document 4) have been developed.

By the way, recently, diversification of displays has progressed, and phosphorescent phosphors with various emission colors according to the place of use and purpose have been desired. In addition, high-intensity phosphorescence that exhibits natural white light emission that is particularly easy on the eyes. Fluorescent phosphors are strongly desired.
Conventionally, as a white light emitting phosphor phosphorescent, for example, a composition formula _{(Ca 1-p-q-} r Eu p Nd q Mn r) O · (Al 1-m B m) 2 O 3 · kP 2 O ₅ is known (Patent Document 5), but its afterglow characteristics are not sufficient, and its white chromaticity value is almost (x / y = 0.300 / 0.430). In addition, the color purity is poor compared to the desired white chromaticity (x / y = 0.300 / 0.300) and is not practically used.

Further, Patent Document 6 discloses that a phosphorescent phosphor having a first emission spectrum by absorbing energy of an excitation source and a first emission spectrum that is different from at least a part of the first emission spectrum. A fluorescent material composed of a plurality of fluorescent materials with a second fluorescent material having a second emission spectrum, and a fluorescent material in which a phosphorescent fluorescent material having the first emission spectrum and a second fluorescent material are formed in layers, respectively. A fluorescent lamp using a fluorescent material as a substance is described.
Examples of phosphorescent phosphors having the first emission spectrum include sulfide phosphors, aluminate phosphors activated by specific rare earth elements, and oxysulfide phosphors. The second fluorescent material includes Ce-activated yttrium oxide / aluminum-based fluorescent material, nitride-based fluorescent material activated by rare earth elements, oxynitride-based fluorescent material activated by rare earth elements, Eu The silicate type fluorescent material activated by is exemplified.

However, the fluorescent lamp and the light emitting device to which the fluorescent material described in Patent Document 6 is applied include a fluorescent film in which two kinds of phosphors are applied in layers, and has a structure using special transmitted light. Further, according to Patent Document 6, even if the emission color is closest to true white, the chromaticity point is approximately x / y = 0.302 / 0.375, and true white (chromaticity point x / y = 0.300 / 0.300), and the afterglow emits light with poor purity as white.
Therefore, it is stimulated by ultraviolet light in sunlight, which is external light, and fluorescent lamps containing ultraviolet light, and the intensity of afterglow is high, the persistence time is long, and especially white afterglow with good color purity. Development of application products of phosphorescent phosphors to be exhibited and phosphorescent phosphors such as display boards is desired.

Japanese Patent No. 3257842 Japanese Patent No. 2543825 Japanese Patent No. 2,697,688 JP 2004-359701 A JP-A-8-151573 JP 2005-330459 A

  The present invention has been made in view of the above circumstances, and has a high afterglow intensity after being excited by ultraviolet rays such as ultraviolet rays, sunlight including ultraviolet rays, and fluorescent lamps, and the excitation light (ultraviolet rays) is blocked. Particularly, phosphorescent white light-emitting phosphor capable of sustaining white afterglow with better color purity than conventional ones, and a fluorescent lamp, phosphorescent display, and phosphorescent molded product using the phosphor It is an issue to provide.

  While examining the presence or absence of phosphorescent properties of a large number of phosphors, the present inventors have developed a specific phosphorescent phosphor that emits light when excited by ultraviolet rays, sunlight, or ultraviolet rays in a fluorescent lamp, and the emission of this phosphor. A mixed phosphor composed of a specific phosphor that absorbs at least a part and emits light in a color complementary to the light emission of the phosphorescent phosphor has a good white light emission with a higher white purity than the conventional phosphor. In addition, the present inventors have found that a storage white light-emitting phosphor that maintains a constant emission intensity even after the excitation source is shut off and has an excellent storage property can be obtained. The above-mentioned problems have been solved by using it as a phosphorescent display body in a part, and by making it into a molded product by containing it in a plastic or the like.

(1) The phosphorescent white light-emitting phosphor of the present invention includes a first phosphor that absorbs ultraviolet rays and emits long afterglow light in the first wavelength region, and at least emits light in the first wavelength region. It is a phosphor formed by mixing or adhering a second phosphor that absorbs a part and emits light in the second wavelength region, and has a chromaticity coordinate of the light emission of a P point (0.200, 0.200), Q point (0.300, 0.400), R point (0.400, 0.400), and quadrangular sides surrounded by S point (0.300, 0.200) Above and inside (however, excluding the line connecting point P and point Q. The range of chromaticity coordinates is hereinafter referred to as “inside of a quadrangle surrounded by four points”) and a regular light source After irradiating with a D65 fluorescent lamp for 20 minutes at an illuminance of 200 lx, the afterglow of 10 minutes after the irradiation was cut off Degrees _{(I [10]),} characterized in that at 110mcd / ^{m 2} or more.

(2) Further, in the phosphorescent white light-emitting phosphor of the present invention, the chromaticity coordinates of the P point are (0.200, 0.200) and the chromaticity coordinates of the Q point are (0.300, 0.400). ), The chromaticity coordinates of the R point are (0.400, 0.400), and the chromaticity coordinates of the S point are (0.250, 0.200).

(3) Further, in the phosphorescent white light-emitting phosphor of the present invention, the chromaticity coordinates of the P point are (0.220, 0.240), and the chromaticity coordinates of the Q point are (0.275, 0.350). The chromaticity coordinates of the R point are (0.350, 0.350), and the chromaticity coordinates of the S point are (0.270, 0.240).

(4) The fluorescent lamp of the present invention is characterized in that the phosphorescent white light-emitting phosphor described in any one of (1) to (3) is a fluorescent film.

(5) A phosphorescent white light-emitting fluorescence according to any one of (1) to (3), wherein at least a character and / or a figure and / or an image of the display portion of the phosphorescent display body of the present invention is any one of the above (1) to (3). It is formed by the body.

(6) The phosphorescent molded article of the present invention contains the phosphorescent white light-emitting phosphor described in any one of (1) to (3).

In the phosphorescent white light-emitting phosphor of the present invention, the chromaticity coordinates of afterglow after excitation light is blocked by the selection of the first phosphor and the second phosphor are P points (0.200, 0. 200), Q point (0.300, 0.400), R point (0.400, 0.400), and S point (0.300, 0.200). It exhibits a white color with good color purity and, for example, after irradiation for 20 minutes at an illuminance of 200 lx with a fluorescent lamp of the ordinary light source D65, the intensity (I _{[ 10]} ) exhibits an emission intensity of 110 mcd / m ² or more, has better color purity than the conventional one, and exhibits long afterglow.
In addition, the fluorescent lamp, phosphorescent display and phosphorescent molded product using the phosphorescent white light-emitting phosphor of the present invention as a phosphor film maintain white afterglow with high brightness and high color purity even after the excitation source is cut off. be able to.

Hereinafter, the present invention will be described in more detail.
The phosphorescent phosphor of the present invention includes the following first phosphor that is excited by ultraviolet light, sunlight, or ultraviolet light in a fluorescent lamp, and emits long afterglow light in the first wavelength range. It is made of a mixture with a second phosphor that is excited by absorbing at least a part of the light emission of the second phosphor and emits light in a wavelength region different from the first wavelength region (second light emission).
The phosphorescent phosphor of the present invention is configured as described above, so that when excited by excitation light (ultraviolet rays), the first phosphor is excited by ultraviolet rays and exhibits first emission, Since the phosphor is excited by the light emission of the first phosphor and exhibits the second light emission, the phosphor exhibits a white light emission that is a mixed color light of the first and second light emission.
Even after the excitation light is blocked, the second phosphor absorbs the afterglow of the first emission emitted by the first phosphor and is excited to exhibit the second emission, so that the excitation light is blocked. Even after that, it is possible to continue white light emission having a much better color purity than the conventional light that is fluorescence of mixed color light of the first light emission (afterglow) and the second light emission.

  The first phosphor is a so-called phosphorescent phosphor that is excited by ultraviolet rays and exhibits long afterglow emission alone. Examples of the first phosphor used in the present invention include Sr, Mg, and the like. In addition, a magnesium silicate / strontium-based phosphor obtained by co-activating a composite oxide containing Si and Si as a matrix constituent metal component with Eu and Dy is used.

From the viewpoint of afterglow intensity and duration, the first phosphor used is, among the magnesium silicate / strontium phosphors, particularly the composition formula m (Sr _1-a M ¹ _a ) O · n. (Mg _1-b M ² _b ) O 2 (Si _1-c Ge _c ) O ₂ : Eux _, Dy _y (where M ¹ is one or more elements selected from Ca and Ba, M ² is one or more elements selected from Be, Zn and Cd, wherein a, b, c, x, m, n, x and y are 0 ≦ a ≦ 0.80 and 0 ≦ b, respectively. ≦ 0.2, 0 ≦ c ≦ 0.2, 1.5 ≦ m ≦ 3.5, 0.5 ≦ n ≦ 1.5, 1 × 10 ⁻⁵ ≦ x ≦ 1 × 10 ⁻¹ and 1 × 10 phosphor is more preferably represented by ^-5 ≦ y ≦ 1 a × 10 ^-1 satisfies number made), formula _{Sr 2 MgSi 2 O 7: Eu} , represented by Dy That the phosphor is particularly preferred.
In the magnesium silicate / strontium phosphor, 0.1 g or less of halogen (X) is added to 1 mol of each phosphor matrix, or 0.6 g or less of boron (B). By containing, the intensity | strength of the light emission and the afterglow can be raised more.

  The second phosphor used in the present invention absorbs at least a part of the light emission (first light emission) of the first phosphor, and is excited by this light emission to emit light different from the first light emission. Since the first phosphor exhibits blue light emission, the second phosphor has a yellowish color that is complementary to the emission color of the first phosphor. A phosphor that emits light or a mixed phosphor of a green light-emitting phosphor and a red light-emitting phosphor is selected.

For example, the as the second phosphor, the composition formula _{(Y 1-x-y Gd} x Sm y) 3 Al 5 O 12: Ce, rare earth aluminate fluorescent that coactivation by Ce and Tb represented by Tb When a phosphor is used, the wavelength matching between the excitation spectrum of the phosphor and the emission spectrum of the first phosphor is very good. It is an overlap between the wavelength range of the emission of the first phosphor (first emission) and the excitation wavelength range of the rare earth aluminate phosphor (second phosphor) co-activated with Ce and Tb. This is because the area is wide, and the second phosphor is efficiently excited by the afterglow (first light emission) of the first phosphor and emits light with extremely high light emission efficiency. It is particularly preferable because the luminescence can be sustained.

FIG. 1 is a graph illustrating an emission spectrum when the first phosphor, which is one component of the phosphorescent white light-emitting phosphor of the present invention, is excited with ultraviolet light having a wavelength of 365 nm. It is an emission spectrum of Sr ₂ MgSi ₂ O ₇ : Eu, Dy phosphor, which is one of the phosphors belonging to the strontium-based phosphor.
As shown in FIG. 1, the magnesium silicate / strontium-based phosphor emits blue light having a peak wavelength of an emission spectrum at about 467 nm.

FIG. 2 shows an emission spectrum when the second phosphor, which is the other component of the phosphorescent phosphor of the present invention, is excited with light having a wavelength of 460 nm (light close to the emission peak wavelength of the first phosphor). Curves c, d and e are improved (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphor, (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphor, And an emission spectrum of Y ₃ Al ₅ O ₁₂ : Ce, Tb phosphor. Incidentally, the above _{(Y, Gd) 3 Al 5} O 12: Ce The phosphor improved products of, obtained by firing once _{(Y, Gd) 3 Al 5} O 12: Ce, phosphor under certain atmosphere Phosphor with improved emission brightness by re-firing (product name “KX-692B” manufactured by Kasei Optonics Co., Ltd., hereinafter referred to as an improved product of (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphor ).
As can be seen from FIG. 2, the second phosphor exhibits yellowish emission having a peak wavelength of the emission spectrum at 560 to 580 nm.

FIG. 3 shows an excitation spectrum for obtaining the light emission of each of the second phosphors (the light emission at the emission peak wavelength of the phosphor that excites the phosphor and the light emitted when the excitation light is irradiated). The curve f, the curve g, and the curve h are (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphor, and the (Y, Gd) ₃ Al _{5 described above.} It is an emission excitation spectrum of an improved product of O ₁₂ : Ce phosphor and Y ₃ Al ₅ O ₁₂ : Ce, Tb phosphor.

As can be seen from FIGS. 1 and 3, the peak wavelength of the excitation spectrum of the second phosphor, which is one component of the phosphorescent white phosphor of the present invention, is in a wavelength region centered around 460 nm, Matching with the emission peak wavelength region of the first phosphor as a component, particularly the Sr ₂ Mg ₂ SiO ₇ : Eu, Dy phosphor (curve in FIG. 1) is extremely good. This indicates that the second phosphor exhibits efficient yellow light emission by the light emission of the first phosphor, and exhibits high efficiency white light emission by mixing with the blue light emission of the first phosphor. ing.

  In particular, when the magnesium silicate / strontium-based phosphor is used as the first phosphor, and the improved rare earth aluminate phosphor activated with Ce is used as the second phosphor, the first phosphor Since the first phosphor exhibits blue light emission with good color purity and the second phosphor exhibits yellow light emission with good color purity, the phosphorescent phosphor composed of this combination is irradiated with excitation light (ultraviolet rays). Not only when the excitation light is blocked, but also the afterglow after the excitation light is blocked can exhibit white light emission with high color purity.

The phosphorescent white phosphor of the present invention is produced by mechanically mixing a predetermined amount of the first phosphor and the second phosphor by a mixing means such as a ball mill or a V-con. Can do.
Further, the first phosphor and the second phosphor are suspended and mixed in a solvent containing a binder such as acrylic resin and gelatin, and then solid-liquid separation is performed, followed by dehydration and drying. Even if the first phosphor and the second phosphor are attached to each other through a binder by a method, they can be produced.
However, rather than simply mixing the first phosphor having the long afterglow and the second phosphor, it is more effective to coat the surface of the first phosphor with the second phosphor. This is more preferable because it can increase the emission intensity.

In the phosphorescent white light-emitting phosphor of the present invention thus obtained, the chromaticity points of the light emission are P point (0.200, 0.200) and Q point (0.300) of the chromaticity coordinates shown in FIG. , 0.400), R point (0.400, 0.400), and S point (0.300, 0.200). After irradiation for 20 minutes at an illuminance of 200 lx, the intensity of afterglow (I _[10] ) after 10 minutes from the time when the irradiation was cut off is 110 mcd / m ² or more, which is longer afterglow than the conventional one. And emits white light with good color purity. Then, the chromaticity coordinates of the P point are (0.220, 0.240) and the chromaticity coordinates of the Q point are selected by selecting the types of the first phosphor and the second phosphor and the mixing ratio thereof. (0.275, 0.350), the chromaticity coordinate of the R point is (0.350, 0.350), and the chromaticity coordinate of the S point is (0.270, 0.240). An accumulative white light emitting phosphor that exhibits a higher purity white light emission within the table range is obtained.

  In the present invention, the afterglow characteristic of each phosphorescent white light-emitting phosphor is such that the illuminance on the surface of the phosphor powder is 200 lx brightness on the powder of the phosphor to be measured whose surface is smoothed. The fluorescent light of the ordinary light source D65 is irradiated for 20 minutes in such a direction that the luminous flux is substantially perpendicular to the surface of the phosphor powder, and the fluorescence after a certain time has passed since the irradiation was stopped. Evaluation was made by comparing the luminous intensity of the body (intensity of afterglow).

In the phosphorescent white light-emitting phosphor of the present invention, the mixing ratio of the first phosphor and the second phosphor is appropriately selected according to the desired emission color of the obtained phosphor, but the emission chromaticity coordinate is 4 of P point (0.200, 0.200), Q point (0.300, 0.400), R point (0.400, 0.400), and S point (0.300, 0.200) The intensity of the afterglow (I _[10] ) 10 minutes after the irradiation was interrupted after being irradiated for 20 minutes at an illuminance of 200 lx with a fluorescent lamp of the ordinary light source D65, which is inside a rectangle surrounded by dots. In order to obtain a phosphorescent white light-emitting phosphor having 110 mcd / m ² or more, the content of the first phosphor is 30 to 99.5% by weight with respect to the total amount of the phosphorescent white light-emitting phosphor. The content of the phosphor of 2 is 0.5 to 70 weight with respect to the total amount of phosphorescent phosphor Is preferably in the range of), more preferably 30 to 99 wt%, more preferably preferably set to 40 to 98 wt%.

  When the content of the first phosphor is less than 30% by weight with respect to the total amount of the phosphorescent white light-emitting phosphor, the emission intensity based on the first phosphor in the phosphor decreases, and excitation light (ultraviolet light) Since the afterglow intensity based on the first phosphor when the light is blocked is also lowered, the afterglow intensity of the phosphorescent phosphor itself excited by this is likely to be lowered. In particular, when importance is placed on luminance, the content of the first phosphor is preferably 40% by weight or more with respect to the total amount of the phosphorescent white light-emitting phosphor. However, the chromaticity coordinates of the luminescent color of the phosphorescent white light-emitting phosphor, which is a mixed color of the light emission of the first phosphor and the light emission of the second phosphor, are the P point (0.200, 0.200), It shifts to the outside of the quadrangle surrounded by the four points of Q point (0.300, 0.400), R point (0.400, 0.400), and S point (0.300, 0.200), as white The content of the first phosphor is 99.5% by weight or less, preferably 99% by weight or less, more preferably, from the viewpoint of the color purity of the phosphor as a white light emission color. Is preferably 98% by weight or less.

  Further, the particle diameter of the first and second phosphors used in the phosphorescent phosphor of the present invention is not particularly limited, but is arbitrarily selected from a range of about 1 to 3000 μm from the viewpoint of color uniformity. What is necessary is just to select, Preferably it is 5-1000 micrometers. By appropriately selecting the ratio of the particle sizes of the first phosphor and the second phosphor, it is possible to obtain a white color that is close to true white even if the blending ratio of the aforementioned phosphors changes greatly. . However, particularly when used for a lamp, both the first and second phosphors are preferably in the range of 1 to 30 μm.

When two types of phosphors are used, basically, those having color coordinates on a line connecting the chromaticity points of light emission of both phosphors are obtained according to the mixing ratio of the two phosphors. If it is desired to obtain a chromaticity point that deviates from this line, an appropriate pigment is added to absorb a part of the emission color or the first or second phosphor, preferably the first phosphor. By adding the third phosphor that emits light by light emission, an emission color deviating from the above line can be obtained. The amount of the third phosphor added at this time preferably does not exceed the amount of the second phosphor, and is preferably 20% by weight or less based on the total amount of the phosphorescent phosphor of the present invention.
Examples of phosphors that can be suitably used as the third phosphor in the present invention include so-called CASN phosphors such as CaAlSiN ₃ : Eu, for example, so-called SCASN phosphors such as (Sr, Ca) AIN ₃ : Eu, For example, a so-called 258 phosphor such as Ca ₂ Si ₅ N ₈ : Eu, Tm, a so-called BSS phosphor such as (Ba, Sr) ₂ SiO ₄ : Eu, a so-called Ba ₃ Si ₆ O ₁₂ N ₂ : Eu, or the like. Examples include BSON phosphors, so-called CSO phosphors such as CaSc ₂ O ₄ : Ce, and so-called CSMS phosphors such as Ca ₃ (Sc, Mg) ₂ Si ₃ O ₁₂ : Ce.

The fluorescent lamp of the present invention comprises the phosphorescent white light-emitting phosphor of the present invention in a solvent such as water together with a binder such as a low-melting glass powder, a fine metal oxide, or a fine metal borate or phosphate. This is manufactured in the same manner as a conventional fluorescent lamp, except that a phosphor coating slurry is prepared by suspending the slurry in the glass bulb, and this is coated on the inner surface of the glass bulb and dried to form a phosphor layer.
In this case, the phosphorescent white light-emitting phosphor of the present invention is not prepared by mixing the first phosphor and the second phosphor in advance, but the second phosphor is applied to the glass tube wall side, Next, the first phosphor is applied on the side (the side where ultraviolet rays are generated by discharge), thereby forming a phosphor film in which the first phosphor and the second phosphor are laminated on the glass tube wall. Also good.

  In the fluorescent lamp of the present invention, the first phosphor emits light (first light emission) by the ultraviolet light generated by the discharge in the mercury vapor sealed in the glass bulb, and is generated by the discharge of mercury vapor or a rare gas. The second phosphor emits light (second light emission) by absorbing the ultraviolet light to be emitted and the first light emission by the first phosphor, and emits mixed color light of the first light emission and the second light emission. And even if the energization to the fluorescent lamp is stopped, since the first light emission by the first phosphor continues, the first phosphor (afterglow) is absorbed by the second phosphor in the phosphor film, Excited to emit second light and continue to emit white light with high color purity, which is a mixed color light of the first light emission (afterglow) and the second light emission even when the energization to the fluorescent lamp is stopped. .

  The phosphorescent display of the present invention has a character and / or figure and / or figure on one side or both sides of a base material such as a plastic such as acrylic resin or vinyl chloride resin, a metal plate, wood, tile, etc. A display unit on which an image is formed is provided. Characters, figures, and images to be displayed are, for example, a plate-like plastic that is coated with paint, ink, or the like containing the phosphorescent phosphor of the present invention, or that phosphorescent phosphor is mixed and has phosphorescence itself. The molded article such as the above-mentioned base material, it may be further written on the surface with various colors of paint, ink, etc., or may be used as a display unit by drawing figures and images, the phosphorescent display of the present invention, A display body using the phosphorescent phosphor of the present invention is included in at least a part of the display portion composed of characters, figures, and images.

  As a specific example of the phosphorescent display body of the present invention, for example, a display unit that displays the direction of the emergency exit or the escape staircase on the substrate using the phosphorescent phosphor of the present invention is provided on at least one surface. Examples thereof include an evacuation guide sign and a guide light in which a backlight made of a fluorescent lamp or the like is housed in a box having a rectangular parallelepiped shape or a cylindrical shape. In the phosphorescent display body of the present invention, such as an evacuation guide sign or guide light provided with a backlight behind the display unit, the phosphorescent property of the present invention used in the display unit even when the backlight is turned off due to a power failure or the like Since the phosphor exhibits afterglow, and the second phosphor is excited by this afterglow and continues to emit light, the display unit displays the mixed light of the first phosphor and the second phosphor even in the dark. The characters and figures drawn on the can be visually recognized.

  Conventionally, there is no phosphorescent phosphor exhibiting high luminance, long afterglow, and good white light emission, so for example, an evacuation guide sign having a display portion on which a figure of a person walking is drawn is unavoidable. Although the graphic part is black and the background is displayed in green, the phosphorescent display body of the present invention exhibits particularly high luminance white light emission (afterglow). As with the guide light, the figure of the person can be green, and the background can be realized as white using the phosphorescent phosphor of the present invention.

The luminous display of the present invention is not limited to using a backlight as described above, but may be plate-shaped or sheet-shaped and installed in a predetermined place such as an indoor or outdoor wall or floor. In that case, even if it is excited by a fluorescent lamp or ultraviolet rays in sunlight from the outside of the display unit, the phosphorescent phosphor of the display unit emits light, and the fluorescent lamp or sunlight is cut off and becomes dark as described above. Similarly, characters and figures on the display unit for a certain period can be visually recognized.
As other specific examples of the phosphorescent display material of the present invention, a clock face plate using the phosphorescent phosphor of the present invention, an image or the like is drawn on the display portion with a paint containing the phosphorescent phosphor of the present invention. A wall surface display in which the display unit is stored in a forehead or the like, or a sheet having the entire display unit made of the phosphorescent phosphor of the present invention is installed on the wall surface, so that it is possible to provide wall surface illumination during a power failure.

In addition, the phosphorescent molded product of the present invention is a powder of the phosphorescent phosphor of the present invention applied to a raw material of plastic resin or synthetic rubber conventionally used as a raw material for molded products such as acrylic resin, vinyl chloride resin and synthetic rubber. It is manufactured by adding and molding into a desired two-dimensional or three-dimensional shape, or mixing it into a raw material such as glass, ceramic or tile and molding it into a desired shape. .
Examples of the phosphorescent molded product of the present invention include molded products including toys, fishing gear, indoor switch plates, accessories, etc., but the phosphorescent phosphor of the present invention is a resin, ceramics, glass or the like. As long as it is a molded product dispersed and contained in a molding substrate such as the above, it is not particularly limited to its shape, use environment or application.
EXAMPLES Next, although an Example demonstrates this invention, this invention is not limited to an Example, unless the summary is exceeded.

[Examples 1-3]
A long afterglow phosphor (hereinafter referred to as phosphor “A”) represented by the composition formula Sr ₂ MgSi ₂ O ₇ : Eu, Dy is used as the first phosphor, and the composition formula (Y Gd) ₃ Al ₅ O ₁₂ : A yellow light-emitting phosphor represented by Ce (hereinafter referred to as phosphor “C”), and the phosphor 1 and the phosphor 2 are respectively shown in the ratios shown in Table 1. By mixing, the phosphorescent white light-emitting phosphors of Examples 1 to 3 were obtained.
The resulting phosphorescent white light-emitting phosphor is irradiated with 365 nm ultraviolet light, and the chromaticity value of the light emission of each phosphor, and the intensity of afterglow after 10 minutes from the time when the irradiation of the fluorescent light of the ordinary light source D65 is cut off. Table 1 shows (I _[10] ) and the intensity of afterglow after 60 minutes (I _[60] ). Moreover, the chromaticity point of each fluorescent substance of Examples 1-3 is shown in FIG.
In Examples 1 to 3, and in the following examples and comparative examples, the illumination of the fluorescent light of the regular light source D65 means that irradiation with 200 lx was performed for 20 minutes with the fluorescent light of D65 as described above. .

[Examples 4 to 6]
(Y, Gd) ₃ Al is a yellow light-emitting phosphor obtained by using the phosphor “A” of Example 1 as the first phosphor and improving the phosphor “C” as the second phosphor. ₅ O ₁₂ : an improved product of Ce (manufactured by Kasei Optonix, product number: KX-692B, phosphor “C”) which is further manufactured by adding additives and changing manufacturing conditions such as firing temperature and atmosphere. Hereinafter, phosphors “D”) were used and mixed at the mixing ratios shown in Table 1 to obtain phosphorescent white light-emitting phosphors of Examples 4 to 6, respectively.
The resulting phosphorescent white light-emitting phosphor is irradiated with 365 nm ultraviolet light, and the chromaticity value of the light emission of each phosphor, and the intensity of afterglow after 10 minutes from the time when the irradiation of the fluorescent light of the ordinary light source D65 is cut off. Table 1 shows (I _[10] ) and the intensity of afterglow after 60 minutes (I _[60] ). Moreover, the chromaticity point of each fluorescent substance of Examples 4-6 is shown in FIG.

[Examples 7 to 9]
The phosphor “A” of Example 1 was used as the first phosphor, and the yellow light-emitting phosphor represented by the composition formula Y ₃ Al ₅ O ₁₂ : Ce, Tb (hereinafter, phosphor “ E ”) and mixed at the ratios shown in Table 1 to obtain phosphorescent white light-emitting phosphors of Examples 7 to 9.
With respect to the obtained phosphorescent phosphor, the chromaticity value of light emission of each phosphor when irradiated with ultraviolet light of 365 nm, and the intensity of afterglow 10 minutes after the point of time when the fluorescent light of the ordinary light source D65 is cut off (I _[10] ) and the intensity of afterglow after 60 minutes (I _[60] ) are shown in Table 1, respectively. Moreover, the chromaticity point of each fluorescent substance of Examples 4-6 is shown in FIG.

[Comparative example]
60 parts by weight: 40 weight parts of the phosphor represented by the composition formula Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy (hereinafter referred to as phosphor “F”) and the phosphor “C” used in Example 1 The phosphorescent phosphor of Comparative Example was obtained by mixing at a ratio of parts.
With respect to the obtained phosphorescent phosphor of the comparative example, the chromaticity value of light emission of each phosphor when irradiated with ultraviolet rays of 365 nm, and the afterglow after 10 minutes from the point of time when the irradiation of the fluorescent light of the ordinary light source D65 was cut off. Table 1 shows the intensity (I _[10] ) and the intensity of afterglow after 60 minutes (I _[60] ). Moreover, the chromaticity point of the phosphor of this comparative example is shown in FIG.

[Reference example]
For the phosphor “A” used in the examples and comparative examples, the emission chromaticity when irradiated with ultraviolet light of 365 nm, and the intensity of afterglow (I _{[10 ] And} afterglow intensity (I _[60] ) after 60 minutes are shown in Table 1 as reference examples. Moreover, the chromaticity point of the phosphor of this reference example is shown in FIG.

As can be seen from Table 1, in the phosphorescent white phosphors (Examples 1 to 9) of the present invention, unlike the conventional phosphorescent phosphor (comparative example), the chromaticity point of the light emission is the P point (0. 200, 0.200), Q point (0.300, 0.400), R point (0.400, 0.400), and a quadrangle surrounded by S point (0.300, 0.200) In addition, the afterglow intensity (I _[10] ) in the powder 10 minutes after blocking the excitation light is larger than that of the conventional phosphorescent phosphor (comparative example). The value is at least higher than 110 mcd / cm ² , and the light emission intensity is practically sufficient as a phosphorescent phosphor.

In Examples (1) and (4) to (9), since the emission color is shifted to a longer wavelength than the first phosphor used as the component, it approaches a luminance measurement visibility curve. It was brighter than the first phosphor used as the component. In addition, fluorescent lamps, display bodies, and phosphorescent molded products using this phosphor can be made brighter than the afterglow luminance of the powder by optimizing the concentration and the like, and the visibility in the dark is also good.
Further, by adjusting the mixing ratio of the first phosphor and the second phosphor, which are the constituent components, and selecting the type of the second phosphor, for example, the phosphorescent phosphor of Example 5 A phosphorescent white light-emitting phosphor having a chromaticity point of light emission of 0.300 / 0.308 and a particularly good white purity compared with the conventional one and exhibiting high-luminance white light emission and its application products can get.

Which is one component of the phosphorescent phosphor of the present invention, the first phosphor _{(Sr 2 MgSi 2 O 7:} Eu, Dy phosphor) is a graph illustrating the emission spectrum of the. Which is another component of the stimulable phosphor of the present invention, is a graph illustrating the emission spectrum of the second phosphor, respectively curve c, the curves d and the curve _{e (Y, Gd) 3 Al} 5 O 12 : Ce phosphor, (Y, Gd) ₃ Al ₅ O ₁₂ : Emission spectrum of improved Ce phosphor and Y ₃ Al ₅ O ₁₂ : Ce, Tb phosphor. The excitation spectrum for obtaining the light emission of each of the second phosphors (FIG. 2) is illustrated, and the curves f, g and h are (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphors, respectively. , (Y, Gd) ₃ Al ₅ O ₁₂ : Ce phosphor improved product, and Y ₃ Al ₅ O ₁₂ : Ce, Tb phosphor emission excitation spectrum. It is a figure which shows the chromaticity point of the luminescent color of each fluorescent substance of the Example of this invention, a comparative example, and a reference example.

Claims (6)

A first phosphor that absorbs ultraviolet rays and emits long afterglow in the first wavelength range; and absorbs at least a portion of the emission in the first wavelength range to emit light in the second wavelength range. The phosphors are mixed with each other or adhered to each other, and the chromaticity coordinates of the emission are P point (0.200, 0.200), Q point (0.300, 0. 400), R point (0.400, 0.400), and S point (0.300, 0.200) on the side of the rectangle surrounded by four points, and the inside thereof (however, P point and Q point The intensity of the afterglow (I _[10] ) 10 minutes after the irradiation was interrupted for 20 minutes at a luminance of 200 lx with the fluorescent lamp of the ordinary light source D65, A phosphorescent white light-emitting phosphor characterized by being 110 mcd / m ² or more. The chromaticity coordinates of the P point are (0.200, 0.200), the chromaticity coordinates of the Q point are (0.300, 0.400), and the chromaticity coordinates of the R point are (0.400,0). 400), and the chromaticity coordinates of the S point are (0.250, 0.200). The chromaticity coordinates of the P point are (0.220, 0.240), the chromaticity coordinates of the Q point are (0.275, 0.350), and the chromaticity coordinates of the R point are (0.350, 0). . 350) and the chromaticity coordinates of the S point are (0.270, 0.240). A fluorescent lamp comprising the phosphorescent white light-emitting phosphor according to any one of claims 1 to 3 as a fluorescent film. A phosphorescent display body, wherein at least part of characters and / or graphics and / or images of the display section is formed of the phosphorescent white light-emitting phosphor according to claim 1. A phosphorescent molded article containing the phosphorescent white light-emitting phosphor according to any one of claims 1 to 3.

Images