JP2014170895A - Wavelength conversion member and light-emitting device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light-emitting device having excellent binning characteristics in which change in color tone due to shift of excitation wavelength is suppressed.SOLUTION: In a light-emitting device including a wavelength conversion member, having a peak wavelength of 530-550 nm of emission wavelength spectrum when excited at 450 nm and containing a yellowish green phosphor, the rate of change of excitation spectrum intensity is set to 0.25 or less at an emission wavelength of 540 nm of the wavelength conversion member.

Description

  The present invention relates to a light emitting device, and particularly to a light emitting device including a blue semiconductor light emitting element. The present invention also relates to a wavelength conversion member that is preferably applied to a light emitting device using a blue semiconductor light emitting element as an excitation source.

  Light-emitting devices using semiconductor light-emitting elements are increasing in presence as energy-saving light-emitting devices. On the other hand, various problems have arisen as the development of light-emitting devices using semiconductor light-emitting elements progresses.

  For example, Patent Document 1 has found a problem that color unevenness occurs in the illumination light as the lighting time becomes longer. To cope with this problem, two types of phosphors that generate visible light of the same color are provided, and the slopes of the excitation spectra of the two types of phosphors are reversed at the emission peak wavelength of the semiconductor light emitting device. It has been proposed (see Patent Document 1).

On the other hand, Patent Document 2 discloses "LED binning" as a problem, and discloses a multi-cell LED circuit having a plurality of cells having binning classes depending on emission wavelength characteristics and luminance characteristics, and an impedance element (patent). Reference 2).
Patent Document 3 discloses that the LED is binned from any viewpoint among the light peak wavelength, the light peak intensity, and the forward voltage, and in particular, the chromaticity is self-adjusted according to the fluctuation of the LED excitation wavelength. A “smart” phosphor composition is disclosed (see Patent Document 3).

  In addition, Patent Document 4 proposes a semiconductor light-emitting device in which the chromaticity variation is reduced with respect to the variation of the peak wavelength of the semiconductor light-emitting element. There has been proposed a semiconductor light emitting device having a first phosphor whose excitation intensity increases with an increase, and a second phosphor whose excitation intensity is flattened or decreased as the wavelength increases (see Patent Document 4).

JP 2005-228833 A Special table 2009-503831 Special table 2010-500444 gazette JP 2008-135725 A

Although LED binning has been pointed out in several documents, no specific proposal has been made for practical use. When the present inventors examined the combination of the phosphors according to the above documents, Patent Document 3 tried to solve the problem by adding an orange phosphor to the yellow phosphor, but suppressed the change in chromaticity. This is not enough for practical use. Further, in Patent Document 4, although an attempt is made to suppress a change in chromaticity by combining a yellow phosphor and an orange phosphor, color rendering properties and light emission efficiency are insufficient.
The present invention solves such problems and provides a light-emitting device having a binning characteristic that can withstand practical use. The present invention also relates to a wavelength conversion member that can provide a light-emitting device having binning characteristics that can be put to practical use when applied to a light-emitting device.

  The present inventors have intensively studied to solve the above-mentioned problems, and have focused on the excitation spectrum of the phosphor, which indicates how much light the phosphor emits at what excitation wavelength. In particular, the excitation spectrum in the vicinity of 450 nm light, which is the wavelength of light emitted from the blue semiconductor light emitting element, was examined in detail. As a result, the wavelength conversion member includes a specific phosphor and a yellow-green phosphor having an emission wavelength spectrum having a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm, and the emission wavelength of the wavelength conversion member is 540 nm. It has been conceived that the problem can be solved by using a wavelength conversion member having a rate of change in excitation spectrum intensity at or below a certain level.

The first aspect of the present invention is:
A light emitting device including a blue semiconductor light emitting element and a wavelength conversion member,
The wavelength conversion member is represented by the following general formula (X), and includes a yellow-green phosphor whose emission wavelength spectrum has a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm,
In this light-emitting device, the wavelength conversion member has an excitation spectrum intensity change rate at an emission wavelength of 540 nm of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.

  The excitation spectrum intensity change rate of the yellow-green phosphor is preferably 0.13 or less. However, the excitation spectrum intensity change rate of the yellow-green phosphor is the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the yellow-green phosphor at 450 nm is 1.0. Expressed as a difference.

Further, when the emission wavelength of the blue semiconductor light emitting element is continuously changed from 445 nm to 455 nm, the chromaticity change Δu′v ′ of light emitted from the light emitting device satisfies Δu′v ′ ≦ 0.005. It is preferable to satisfy. However, Δu′v ′ is the distance between the chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength inm from 445 nm to 455 nm and the average value (u ′ _ave , v ′ _ave ) of chromaticity from 445 nm to 455 nm. .

In addition, the yellow-green phosphor is preferably a yellow-green phosphor represented by the following general formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is one or more elements selected from the group of Y and Lu and containing 90% or more of Y. E is Ga or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2)

  Moreover, it is preferable that the intensity change of the excitation spectrum of the yellow-green phosphor is 4.0% or less of the excitation light spectrum intensity at 450 nm from 440 nm to 460 nm.

The second aspect of the present invention is:
A blue semiconductor light emitting device;
A light-emitting device including a wavelength conversion member containing a yellow-green phosphor,
The yellow-green phosphor is represented by the following general formula (2), and the difference between the maximum value and the minimum value of the excitation intensity normalized by the excitation intensity of 450 nm when excited at an excitation wavelength of 440 nm to 460 nm is 0.05. The following phosphors:
(Y, Ce) ₃ (Ga, Al) _f O _g (2)
(4.5 ≦ f ≦ 5.5, 10.8 ≦ g ≦ 13.2)
In the light emitting device, the chromaticity change Δu′v ′ from the average chromaticity of the light emitted from the wavelength conversion member when excited at an excitation wavelength of 445 nm to 455 nm is 0.005 or less.
However, Δu′v ′ is the distance between the chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength inm from 445 nm to 455 nm and the average value (u ′ _ave , v ′ _ave ) of chromaticity from 445 nm to 455 nm. .

In the first to second aspects of the present invention, it is preferable to further include a red phosphor, and the intensity change of the excitation spectrum of the red phosphor varies from 440 nm to 460 nm to 4.0 of the excitation light spectrum intensity at 450 nm. % Or less is preferable.
The red phosphor preferably contains 50% or more of a red phosphor having an emission peak wavelength of 620 to 640 nm and a half-value width of 2 nm to 100 nm in a composition weight ratio with respect to the total amount of the red phosphor. The red phosphor is preferably SCASN.

  The red phosphor preferably further includes a red phosphor having an emission peak wavelength of 640 to 670 nm and a half-value width of 2 nm to 120 nm.

  In addition, it is preferable that the light emitted from the light emitting device has a deviation duv from the light-colored black body radiation locus of −0.0200 to 0.0200 and a color temperature of 1800 K or higher and 7000 K or lower, while emitting light. An embodiment in which the color temperature of light emitted from the apparatus is 7000 K or more and 20000 K or less is also preferable.

  Moreover, in the 1st thru | or 2nd aspect of this invention, a blue semiconductor light-emitting device and the wavelength conversion member containing yellowish green fluorescent substance may be arrange | positioned through space.

The third aspect of the present invention is
A yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm to 550 nm when excited at 450 nm;
A wavelength conversion member including a transparent material,
The wavelength conversion member has an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.

The fourth aspect of the present invention is
A yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm to 550 nm when excited at 450 nm;
A phosphor composition comprising a transparent material,
When the phosphor composition is molded into a wavelength conversion member, the phosphor composition has an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.

The fifth aspect of the present invention is as follows.
A phosphor mixture containing a yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm,
The phosphor mixture has a synthetic excitation spectrum intensity change rate at an emission wavelength of 575 nm of 0.12 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the phosphor mixture is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the phosphor mixture at 450 nm is 1.0. It is represented by

According to the first aspect or the second aspect of the present invention, a light emitting device having excellent binning characteristics can be provided. Since these light-emitting devices not only have excellent binning characteristics, but also have high luminous efficiency and high color rendering properties, they can be put to practical use as illumination devices and backlights equipped with these light-emitting devices. In addition, since the luminous efficiency is high and the amount of phosphor used is reduced, there is an economic advantage. In addition, according to the third aspect of the present invention, it is possible to provide a wavelength conversion member that can provide a light emitting device having excellent binning characteristics.
In the first to third aspects of the present invention, conventionally, two types of phosphors, for example, a yellow phosphor and an orange phosphor as described in Patent Document 3 or 4, can be achieved without mixing. The binning characteristic that has not been achieved can be achieved by a simple method using only the yellow-green phosphor.

It is a cross-sectional schematic diagram of the light-emitting device which concerns on one Embodiment of this invention. Chromaticity change Δu ′ when excited at 430 nm to 470 nm for a light emitting device manufactured using a wavelength conversion member containing a GYAG phosphor and having an excitation spectral intensity change rate of 0.25 or less at an emission wavelength of 540 nm It is a graph which shows v '.

Hereinafter, although this invention is demonstrated using an embodiment, this invention is not limited only to a specific embodiment.
Hereinafter, in the phosphor composition formulas in the present specification, each composition formula is delimited by a punctuation mark (,). In addition, when a plurality of elements are listed separated by commas (,), one or two or more of the listed elements may be included in any combination and composition.
The light-emitting devices according to the first and second aspects of the present invention include a wavelength conversion member including a blue semiconductor light-emitting element and a yellow-green phosphor.
The blue semiconductor light emitting device is a semiconductor light emitting device that emits light having an emission peak at 420 nm or more and 475 nm or less. The blue semiconductor light emitting device preferably emits light having an emission peak at 430 nm to 470 nm, and preferably emits light having an emission peak at 445 nm to 455 nm.
The blue semiconductor light emitting element preferably has a half width of 5 nm or more and 30 nm or less from the viewpoint of light emission efficiency.
The blue semiconductor light emitting device is preferably a light emitting diode device having a pn junction type light emitting portion formed of a nitrogen gallium based, zinc oxide based or silicon carbide based semiconductor.

The wavelength converting member is a wavelength converting member that wavelength-converts at least part of incident light and emits outgoing light having a wavelength different from that of the incident light. The wavelength converting member is at least one of the incident light. And a phosphor that emits outgoing light having a wavelength different from that of the incident light. The phosphor is preferably dispersed in a transparent or translucent material that absorbs less visible light such as resin. In addition, the wavelength conversion member may have a self-supporting shape due to the contained transparent material or the like. As yet another aspect, the phosphor may be mixed and applied to a resin or the like on a transparent substrate such as glass if necessary.

The wavelength conversion member used in the first aspect includes a yellow-green phosphor that is represented by the following general formula (X) and has a peak wavelength of an emission wavelength spectrum of 530 nm to 550 nm when excited at 450 nm,
The excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member is 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.

It is preferable that the excitation spectrum intensity change rate of the yellow-green phosphor is 0.13 or less.
However, the excitation spectrum intensity change rate of the yellow-green phosphor is the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the yellow-green phosphor at 450 nm is 1.0. Expressed as a difference.

When the emission wavelength of the blue semiconductor light emitting element is continuously changed from 445 nm to 455 nm, the chromaticity change Δu′v ′ of light emitted from the light emitting device satisfies Δu′v ′ ≦ 0.005. preferable.
However, Δu′v ′ is the distance between the chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength inm from 445 nm to 455 nm and the average value (u ′ _ave , v ′ _ave ) of chromaticity from 445 nm to 455 nm. .

Moreover, it is preferable that the said yellow-green fluorescent substance is shown by following General formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is one or more elements selected from the group of Y and Lu and containing 90% or more of Y. E is Ga or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2)

  The phosphor represented by the general formula (1) has a peak wavelength of an emission wavelength spectrum of 530 nm or more and 550 nm or less when excited at 450 nm, that is, a peak wavelength of an emission wavelength spectrum in a yellow-green region. The phosphors referred to are included.

  The intensity change of the excitation spectrum of the yellow-green phosphor is preferably 4.0% or less of the intensity of the excitation light spectrum at 450 nm from 440 nm to 460 nm. Note that the intensity change of the excitation spectrum is usually calculated based on the emission peak wavelength or a wavelength near it, for example, the intensity at 540 nm.

The inventors pay attention to the excitation spectrum intensity of the phosphor, which indicates how much light the phosphor emits at what excitation wavelength, and particularly the wavelength of the light emitted by the blue semiconductor light emitting element. Excitation spectrum intensity in the vicinity of 450 nm light was examined in detail. As a result, it has been conceived that a high luminance can be achieved in addition to good binning characteristics when the change rate of the excitation spectrum intensity at the emission wavelength of 540 nm of the wavelength conversion member is 0.25 or less.
When the excitation spectrum intensity changes greatly, the fluorescence intensity emitted from the phosphor changes greatly when the excitation wavelength changes, and the chromaticity of the light emitted from the light emitting device is shifted. In this embodiment, the chromaticity deviation of the light emitted from the wavelength conversion member was suppressed by setting the excitation spectrum intensity change rate at the emission wavelength of 540 nm of the wavelength conversion member to 0.25 or less.

  In a blue semiconductor light-emitting element serving as a light source of a light-emitting device, the variation in emission peak wavelength is usually about ± 5 nm. Further, even the blue semiconductor light emitting element having the largest variation is about ± 20 nm. By satisfying the above requirements, the light-emitting device according to this embodiment has excellent binning characteristics in which the chromaticity change of the emitted light is small with respect to the variation in the emission peak wavelength of the blue semiconductor light-emitting element serving as the light source. A light emitting device is preferable.

A light emitting device according to the second aspect includes a blue semiconductor light emitting element,
A light-emitting device including a wavelength conversion member containing a yellow-green phosphor,
The yellow-green phosphor is represented by the following general formula (2), and the difference between the maximum value and the minimum value of the excitation spectrum intensity normalized by the excitation intensity of 450 nm when excited at the excitation wavelength of 440 nm to 460 nm is 0.05. The following phosphors.
(Y, Ce) ₃ (Ga, Al) _f O _g (2)
(4.5 ≦ f ≦ 5.5, 10.8 ≦ g ≦ 13.2)
Since the excitation spectrum intensity normalized with the excitation intensity of 450 nm when excited at an excitation wavelength of 440 nm to 460 nm depends on the Ga concentration, by adjusting the Ga concentration in the range of 4.5 ≦ f ≦ 5.5. The difference between the maximum value and the minimum value of the excitation spectrum intensity can be reduced to 0.05 or less.

  When the phosphors represented by the general formula (1) and the general formula (2) are GYAG phosphors, the half width is preferably 105 nm or more and 120 nm or less from the viewpoint of color rendering.

In this embodiment, the difference between the maximum value and the minimum value of the excitation spectrum intensity normalized with the excitation intensity of 450 nm when excited with an excitation wavelength of 440 nm to 460 nm is set to 0.05 or less, thereby reducing the wavelength conversion member. The chromaticity deviation of the emitted light was suppressed.
Therefore, by providing the wavelength conversion member, the light emitting device in this embodiment has a chromaticity change Δu′v from the average chromaticity of light emitted from the wavelength conversion member when excited at an excitation wavelength of 445 nm to 455 nm. 'Becomes 0.005 or less.
However, Δu′v ′ is an average value (u ′ _i ) of chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength _i nm from 445 nm to 455 nm and chromaticity from 445 nm to 455 nm.
_ave , v ′ _ave ).

  As described above, the light-emitting device according to the second aspect satisfies the above requirements, and has excellent binning characteristics that can withstand practical use even when the variation of the emission peak wavelength of the semiconductor light-emitting element is large. Light emitting device.

The chromaticity (u ′ _i , v ′ _i ) of light emitted from the light emitting device at the arbitrary wavelength inm, and the average value (u ′ _ave , v ′ _a ) of light emitted from the light emitting device at a wavelength in a specific region.
_ve ) is calculated based on the CIE 1976 UCS chromaticity diagram. Specifically, a 20 inch integrating sphere (LMS-200) manufactured by Labsphere and a spectroscope manufactured by Carl Zeiss (So
lid Lambda UV-Vis) is used to obtain a spectrum of light emitted from the light-emitting device, and chromaticity (u ′ _i , v ′ _i ) is calculated based on the spectrum. Then, the calculated chromaticity (u ′ _i , v ′ _i ) is plotted on the u ′ v ′ chromaticity diagram, and the average value (u ′
_ave , v ′ _ave ) are obtained and set as a chromaticity change Δu′v ′.

In the light emitting device according to the first and second aspects of the present invention, the chromaticity at an arbitrary wavelength i nm emitted from the light emitting device by changing the excitation wavelength at least every 3 nm, preferably every 2 nm, more preferably every 1 nm. (U ′ _i , v ′ _i ) are measured and the average value (u ′ _a
ve , v ′ _ave ) is calculated. Then, the distance between chromaticity (u ′ _i , v ′ _i ) and (u ′ _ave , v ′ _ave ) at wavelength inm is obtained.

In the first and second embodiments of the present invention, the distance Δu′v ′ between the chromaticity (u ′ _i , v ′ _i ) and (u ′ _ave , v ′ _ave ) at the wavelength in nm at the excitation wavelength of 445 nm to 455 nm. Are 0.005 or less.
Note that when measuring the average value of the chromaticity of light emitted from the light emitting device, the interval for changing the wavelength may be constant or random.

  In the wavelength conversion member according to the light emitting device of the first aspect and the second aspect, the phosphor represented by the general formula (X), the phosphor represented by the general formula (1), and the general formula (2) There is no particular limitation on the content of the phosphor, and it can be appropriately set according to a request such as a color temperature of light emitted from the light emitting device.

  The blue semiconductor light-emitting element and the wavelength conversion member including the yellow-green phosphor in the light-emitting device according to the first to second aspects of the present invention may be disposed via a space. By taking such an arrangement, it is possible to prevent the yellow-green phosphor contained in the wavelength conversion member from being deteriorated by the thermal energy of the light emitted from the blue semiconductor light emitting element, and to maintain the intensity, luminance, etc. of the phosphor. be able to. There may be a gap between the blue semiconductor light emitting element and the wavelength conversion member containing the yellow-green phosphor, or it may be filled with a filler.

  In the light-emitting device according to the first to second aspects of the present invention, other known phosphors can be added to the wavelength conversion member within a range that does not impair the effects of the present invention. It is included in the scope of the invention.

The light emitting device according to the first to second aspects of the present invention can be suitably applied as a light emitting device used for general illumination or a light emitting device used for a backlight.
The general lighting device including the light emitting device of the present invention is preferably a general lighting device that emits white light, and when applied to such applications, the light emitting device according to the first to second aspects of the present invention. The light emitted from the light emitting device preferably has a deviation duv from the light-colored black body radiation locus of −0.0200 to 0.0200 and a color temperature of 1800 K or more and 7000 K or less.
On the other hand, when the light-emitting device of the present invention is applied to a backlight, the light emitted from the light-emitting device according to the first to second aspects of the present invention has a color temperature greater than 7000K and less than 20000K. It is preferable that

A third aspect of the present invention is a yellow-green phosphor represented by the following general formula (X), wherein the peak wavelength of the emission wavelength spectrum when excited at 450 nm is 530 nm or more and 550 nm or less,
A wavelength conversion member including a transparent material,
The wavelength conversion member has an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.
The description of the first aspect can be applied to each requirement constituting the wavelength conversion member according to the third aspect.

A fourth aspect of the present invention is a phosphor composition capable of forming a wavelength conversion member capable of providing a light emitting device having excellent binning characteristics when applied to the light emitting device.
That is, the fourth aspect of the present invention is a yellowish green phosphor represented by the following general formula (X), wherein the peak wavelength of the emission wavelength spectrum when excited at 450 nm is 530 nm or more and 550 nm or less,
A phosphor composition comprising a transparent material,
When the phosphor composition is molded into a wavelength conversion member, the phosphor composition has an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.
For the yellow-green phosphor, the description of the yellow-green phosphor in the first aspect can be applied.

The fifth aspect of the present invention is a phosphor mixture containing a yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum peak wavelength of 530 nm to 550 nm when excited at 450 nm. There,
The phosphor mixture has a synthetic excitation spectrum intensity change rate at an emission wavelength of 575 nm of 0.12 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the phosphor mixture is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the phosphor mixture at 450 nm is 1.0. It is represented by

When the phosphor mixture and silicone resin are mixed, or polycarbonate resin is kneaded and molded into a wavelength conversion member, the excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member is 0.05 or less. It is preferable that
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 440 nm to 460 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed.
For the yellow-green phosphor, the description of the yellow-green phosphor in the first aspect can be applied.

In the first to fifth aspects of the present invention, it is preferable that a red phosphor (also referred to as a first red phosphor) is further included. By including the first red phosphor, it is possible to improve the color rendering of the light emitted from the light emitting device, and the color temperature of the light emitting device can be easily adjusted.
As a 1st red fluorescent substance, it is preferable that the intensity | strength change of the excitation spectrum when the excitation light wavelength changes from 440 nm to 460 nm is 4.0% or less of the excitation spectrum by 450 nm excitation light. It is more preferably 0% or less, and further preferably 1.0% or less. By using such a red phosphor, it is possible to further improve the color rendering property while making the binning characteristics of the light emitting device sufficient. The lower limit is not particularly limited and is 0% or more.
As red phosphors satisfying such requirements, (Sr, Ca) AlSiN ₃ : Eu, Ca _1-x Al _1-x Si _{1 + x} N _3−x O _x : Eu, K ₂ SiF: Mn ⁴⁺ , Eu _y (Sr, Ca, Ba) _1-y : Al _{1 + x} Si _4-x O _x N _7-x (where 0 ≦ x <4, 0 ≦ y <0.2), etc., (Sr, Ca) AlSiN ₃ : Eu or Ca _1−x Al _1−x Si _{1 + x} N _3−x O _x : Eu is preferable.

The first red phosphor is preferably a red phosphor having an emission peak wavelength of 620 nm or more and less than 640 nm and a half width of 2 nm or more and 100 nm or less. As red phosphors satisfying such requirements, (Sr, Ca) AlSiN ₃ : Eu, Ca _1-x Al _1-x Si _{1 + x} N _3−x O _x : Eu, Eu _y (Sr, Ca, Ba) _1-y : Al _{1 + x} Si _4-x O _x N _7-x (where 0 ≦ x <4, 0 ≦ y <0.2), K ₂ SiF: Mn ^4+, etc. (Sr, Ca) AlSiN ₃ : Eu or Ca _1−x Al _1−x Si _{1 + x} N _3−x O _x : Eu is preferable.
The _{(Sr, Ca) AlSiN 3:} Eu _{is, M a A b D c E} d X e ( wherein, M is Eu, 1 A is selected from Mg, Ca, Sr, the group consisting of Ba 1 or 2 or more elements, D is Si, E is an essential element of Al, and is selected from the group consisting of B, Al, Ga, In, Sc, Y, La, Gd, and Lu. X is an essential element, and X is one or more elements selected from the group consisting of O, N, and F. Also, a, b, c, d , E are 0.00001 ≦ a ≦ 0.1, a + b = 1, 0.5 ≦ c ≦ 1.8, 0.5 ≦ d ≦ 1.8, 0.8 × (2/3 + 4/3) × c + d) ≦ e, e ≦ 1.2 × (2/3 + 4/3 × c + d).
It may be shown by the general formula.
In addition, the first red phosphor having an emission peak wavelength of 620 nm or more and less than 640 nm and a half width of 2 nm or more and 100 nm or less preferably includes 30% or more, preferably 40% or more in a composition weight ratio with respect to the total amount of the red phosphor Is more preferable, and it is particularly preferable to include 50% or more.

In the present invention, it is preferable to include a red phosphor (hereinafter also referred to as a second red phosphor) in addition to the first red phosphor described above or instead of the first red phosphor. More preferably, two kinds of red phosphors are included.
By including the second red phosphor, in addition to the good color rendering due to the addition of the red phosphor, the degree of freedom regarding the type and amount of the phosphor that can be selected in order to achieve a light emitting device that can achieve high conversion efficiency Will increase.

As the second red phosphor, it is preferable that the intensity change of the excitation spectrum when the excitation light wavelength is changed from 440 nm to 460 nm is 5.0% or less of the excitation spectrum by 450 nm excitation light. It is more preferably 0% or less, and further preferably 1.0% or less.
A red phosphor having an emission peak wavelength of 640 nm to 670 nm and a half width of 2 nm to 120 nm is preferable. Examples of such a phosphor include CaAlSiN ₃ : Eu phosphor, 3.5MgO · 0.5MgF ₂ .GeO ₂ : Mn ⁴⁺ phosphor, and the like is preferably a CaAlSiN ₃ : Eu phosphor.
When the second red phosphor is contained, the content is not particularly limited as long as the effects of the present invention are not impaired, but the composition weight ratio with respect to the total amount of the red phosphor is 0.0% or more and 50.0%. The following is preferable.
When the second red phosphor is included, the intensity of the excitation spectrum of the red phosphor mixture when the excitation light wavelength is changed from 440 nm to 460 nm when mixed with the first red phosphor. The change is preferably 5.0% or less of the excitation spectrum by 450 nm excitation light, more preferably 3.0% or less, and further preferably 1.0% or less.

As for the particle size of the phosphor used in the embodiment of the present invention, the volume-based median diameter D _50v is preferably 0.1 μm or more, more preferably 1 μm or more. Moreover, the thing of 30 micrometers or less is preferable, and the thing of 20 micrometers or less can be used more preferably. Here, the volume-based median diameter D _50v is a volume-based relative when a sample is measured and a particle size distribution (cumulative distribution) is obtained using a particle size distribution measuring apparatus based on a laser diffraction / scattering method. It is defined as the particle size at which the particle amount is 50%. As a measuring method, for example, a phosphor is put in ultrapure water, an ultrasonic disperser (manufactured by Kaijo Co., Ltd.) is used, the frequency is 19 KHz, the ultrasonic intensity is 5 W, and the sample is ultrasonicated for 25 seconds. After the dispersion, the transmittance is adjusted to a range of 88% to 92% using a flow cell, and after confirming that the particles are not aggregated, the particle size is measured by a laser diffraction particle size distribution analyzer (Horiba LA-300). The method of measuring in a diameter range 0.1 micrometer-600 micrometers is mentioned. In the above method, when the phosphor particles are aggregated, a dispersing agent may be used. For example, the phosphor is put in an aqueous solution containing 0.0003% by weight of Tamol (manufactured by BASF). In the same manner as described above, the measurement may be performed after ultrasonic dispersion.

As an index indicating the degree of particle size distribution, there is a ratio (D _v / D _n ) between the volume-based average particle diameter D _v and the number-based average particle diameter D _n of the phosphor. In the present invention, D _v / D _n is preferably 1.0 or more, more preferably 1.2 or more, and further preferably 1.4 or more. On the other hand, D _v / D _n is preferably 25 or less, more preferably 10 or less, and particularly preferably 5 or less. If D _v / D _n is too large, there will be phosphor particles with greatly different weights, and the phosphor particles will tend to be non-uniformly dispersed in the phosphor layer.

  Further, as the phosphor, it is also possible to use a phosphor whose surface is previously coated with a third component. The type of the third component used for coating and the coating method are not particularly limited, and any known third component and method may be used.

  Examples of the third component include organic acids, inorganic acids, silane treating agents, silicone oil, liquid paraffin, and the like. By using these third components to surface-treat and coat the phosphor, the affinity to a wavelength conversion member such as a resin, dispersibility, thermal stability, and fluorescence coloring property tend to be improved. The surface treatment and the coating amount are usually 0.01 to 10 parts by weight per 100 parts by weight of the phosphor, and if less than 0.01 parts by weight, the affinity, dispersibility, thermal stability, fluorescence coloring property, etc. The improvement effect is difficult to obtain, and if it exceeds 10 parts by weight, problems such as deterioration of thermal stability, mechanical properties, and fluorescence coloring property are likely to occur.

  In the embodiment of the present invention, the content of the phosphor in the wavelength conversion member depends on the type of the light diffusing material and the resin to be described later. For example, when the resin is a polycarbonate resin, the content is 100 parts by weight of the polycarbonate resin. The amount is usually 0.1 parts by weight or more, preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, and usually 50 parts by weight or less, preferably 40 parts by weight or less, more preferably 30 parts by weight or less. More preferably, it is 20 parts by weight or less. If the content of the phosphor is too small, the wavelength conversion effect of the phosphor tends to be difficult to obtain, and if it is too large, the mechanical properties may deteriorate, which is not preferable.

  The transparent material contained in the wavelength conversion member or the phosphor composition according to the third and fourth aspects of the present invention is not particularly limited as long as it is used when the phosphor is dispersed. It preferably has a refractive index of 7 or less. In addition, the measuring method of the refractive index of a transparent material is as follows. The measurement temperature is 20 ° C., measured by the prism coupler method. The measurement wavelength is 450 nm.

  Table 1 below shows the refractive indexes of resins generally used as transparent materials. In addition, the refractive index of each resin in Table 1 is a general reference value, and the refractive index of each resin is not necessarily limited to the value in Table 1.

  These resins used as the transparent material described above may be used alone or in combination of two or more. Moreover, the copolymer of these resin may be sufficient.

As the transparent material, polycarbonate resin can be most preferably used because it is excellent in transparency, heat resistance, mechanical properties, and flame retardancy.
When the transparent material is a polycarbonate resin, the yellow-green phosphor is usually 0.1 parts by weight or more, preferably 0.5 parts by weight or more, more preferably 1 part by weight or more with respect to 100 parts by weight of the polycarbonate resin. The phosphors according to the fourth and fifth aspects of the present invention are usually dispersed in an amount of 50 parts by weight or less, preferably 40 parts by weight or less, more preferably 30 parts by weight or less, and even more preferably 20 parts by weight or less. A composition can be obtained. If the content of the yellow-green phosphor is too small, it tends to be difficult to obtain the wavelength conversion effect of the phosphor, and if it is too large, the mechanical properties may be deteriorated.
Hereinafter, the polycarbonate resin will be described in detail.

The polycarbonate resin used in this embodiment is a polymer having a basic structure having a carbonic acid bond represented by the following general chemical formula (1).

In the chemical formula (1), X ¹ is generally a hydrocarbon, but for imparting various properties, X ¹ into which a hetero atom or a hetero bond is introduced may be used.

  The polycarbonate resin can be classified into an aromatic polycarbonate resin in which carbon directly bonded to a carbonic acid bond is aromatic carbon and an aliphatic polycarbonate resin in which aliphatic carbon is aliphatic carbon, either of which can be used. Of these, aromatic polycarbonate resins are preferred from the viewpoints of heat resistance, mechanical properties, electrical characteristics, and the like.

Although there is no restriction | limiting in the specific kind of polycarbonate resin, For example, the polycarbonate polymer formed by making a dihydroxy compound and a carbonate precursor react is mentioned. At this time, in addition to the dihydroxy compound and the carbonate precursor, a polyhydroxy compound or the like may be reacted. Further, a method of reacting carbon dioxide with a cyclic ether using a carbonate precursor may be used. The polycarbonate polymer may be linear or branched. Further, the polycarbonate polymer may be a homopolymer composed of one type of repeating unit or a copolymer having two or more types of repeating units. At this time, the copolymer can be selected from various copolymerization forms such as a random copolymer and a block copolymer. In general, such a polycarbonate polymer is a thermoplastic resin.

  Examples of aromatic dihydroxy compounds among monomers used as raw materials for aromatic polycarbonate resins include dihydroxy compounds such as 1,2-dihydroxybenzene, 1,3-dihydroxybenzene (ie, resorcinol), 1,4-dihydroxybenzene, and the like. Benzenes; dihydroxybiphenyls such as 2,5-dihydroxybiphenyl, 2,2′-dihydroxybiphenyl, 4,4′-dihydroxybiphenyl; 2,2′-dihydroxy-1,1′-binaphthyl, 1,2-dihydroxy Dihydroxynaphthalenes such as naphthalene, 1,3-dihydroxynaphthalene, 2,3-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene; 2 , 2 -Dihydroxydiphenyl ether, 3,3'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 1,4-bis (3-hydroxyphenoxy) benzene, 1, Dihydroxydiaryl ethers such as 3-bis (4-hydroxyphenoxy) benzene; 2,2-bis (4-hydroxyphenyl) propane (ie, bisphenol A), 1,1-bis (4-hydroxyphenyl) propane, 2 , 2-bis (3-methyl-4-hydroxyphenyl) propane, 2,2-bis (3-methoxy-4-hydroxyphenyl) propane, 2- (4-hydroxyphenyl) -2- (3-methoxy-4 -Hydroxyphenyl) propane, 1,1-bis (3- ert-butyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 2- ( 4-hydroxyphenyl) -2- (3-cyclohexyl-4-hydroxyphenyl) propane, α, α′-bis (4-hydroxyphenyl) -1,4-diisopropylbenzene, 1,3-bis [2- (4 -Hydroxyphenyl) -2-propyl] benzene, bis (4-hydroxyphenyl) methane, bis (4-hydroxyphenyl) cyclohexylmethane, bis (4-hydroxyphenyl) phenylmethane, bis (4-hydroxyphenyl) (4- Propenylphenyl) methane, bis (4-hydroxyphenyl) diphenylmethane Bis (4-hydroxyphenyl) naphthylmethane, 1-bis (4-hydroxyphenyl) ethane, 2-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1 , 1-bis (4-hydroxyphenyl) -1-naphthylethane, 1-bis (4-hydroxyphenyl) butane, 2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) pentane 1,1-bis (4-hydroxyphenyl) hexane, 2,2-bis (4-hydroxyphenyl) hexane, 1-bis (4-hydroxyphenyl) octane, 2-bis (4-hydroxyphenyl) octane, -Bis (4-hydroxyphenyl) hexane, 2-bis (4-hydroxyphenyl) hexane, 4,4-bis Bis (hydroxyaryl) alkanes such as (4-hydroxyphenyl) heptane, 2,2-bis (4-hydroxyphenyl) nonane, 10-bis (4-hydroxyphenyl) decane, 1-bis (4-hydroxyphenyl) dodecane 1-bis (4-hydroxyphenyl) cyclopentane, 1-bis (4-hydroxyphenyl) cyclohexane, 4-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3, 3-dimethylcyclohexane, 1-bis (4-hydroxyphenyl) -3,4-dimethylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3,5-dimethylcyclohexane, 1,1-bis (4-hydroxy) Phenyl) -3,3,5-trimethylcyclohexane, 1,1-bis (4 Hydroxy-3,5-dimethylphenyl) -3,3,5-trimethylcyclohexane, 1,1-bis (4-hydroxyphenyl) -3-propyl-5-methylcyclohexane, 1,1-bis (4-hydroxyphenyl) ) -3-tert-butyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3-tert-butyl-cyclohexane, 1,1-bis (4-hydroxyphenyl) -3-phenylcyclohexane, 1,1 -Bis (hydroxyaryl) cycloalkanes such as bis (4-hydroxyphenyl) -4-phenylcyclohexane; 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methyl) Bisphenols containing cardo structure such as phenyl) fluorene; 4,4′-dihydroxy Dihydroxy diaryl sulfides such as phenyl sulfide and 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfide; 4,4′-dihydroxydiphenyl sulfoxide, 4,4′-dihydroxy-3,3′-dimethyldiphenyl sulfoxide and the like Dihydroxydiaryl sulfoxides; dihydroxydiaryl sulfones such as 4,4′-dihydroxydiphenylsulfone and 4,4′-dihydroxy-3,3′-dimethyldiphenylsulfone;

  Among these, bis (hydroxyaryl) alkanes are preferable, and bis (4-hydroxyphenyl) alkanes are preferable, and 2,2-bis (4-hydroxyphenyl) propane (ie, from the viewpoint of impact resistance and heat resistance). Bisphenol A) is preferred.

  In addition, 1 type may be used for an aromatic dihydroxy compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the monomer that is a raw material for the aliphatic polycarbonate resin include ethane-1,2-diol, propane-1,2-diol, propane-1,3-diol, 2,2-dimethylpropane-1, 3-diol, 2-methyl-2-propylpropane-1,3-diol, butane-1,4-diol, pentane-1,5-diol, hexane-1,6-diol, decane-1,10-diol Alkanediols such as cyclopentane-1,2-diol, cyclohexane-1,2-diol, cyclohexane-1,4-diol, 1,4-cyclohexanedimethanol, 4- (2-hydroxyethyl) cyclohexanol, Cycloalkanediols such as 2,2,4,4-tetramethyl-cyclobutane-1,3-diol; Glycols such as sidiethanol (ie, ethylene glycol), diethylene glycol, triethylene glycol, propylene glycol, spiroglycol; 1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, 1 , 4-benzenediethanol, 1,3-bis (2-hydroxyethoxy) benzene, 1,4-bis (2-hydroxyethoxy) benzene, 2,3-bis (hydroxymethyl) naphthalene, 1,6-bis (hydroxy Ethoxy) naphthalene, 4,4′-biphenyldimethanol, 4,4′-biphenyldiethanol, 1,4-bis (2-hydroxyethoxy) biphenyl, bisphenol A bis (2-hydroxyethyl) ether, bisphenol S bis (2 -Hydroxyethyl ) Aralkyldiols such as ether; 1,2-epoxyethane (ie, ethylene oxide), 1,2-epoxypropane (ie, propylene oxide), 1,2-epoxycyclopentane, 1,2-epoxycyclohexane, 1, Examples include cyclic ethers such as 4-epoxycyclohexane, 1-methyl-1,2-epoxycyclohexane, 2,3-epoxynorbornane, and 1,3-epoxypropane, and these may be used alone or in combination. The above may be used in any combination and ratio.

Among the monomers used as the raw material for the aromatic polycarbonate resin, examples of the carbonate precursor include carbonyl halide and carbonate ester. In addition, 1 type may be used for a carbonate precursor and it may use 2 or more types together by arbitrary combinations and a ratio.

  Specific examples of the carbonyl halide include phosgene, haloformates such as a bischloroformate of a dihydroxy compound, and a monochloroformate of a dihydroxy compound.

  Specific examples of the carbonate ester include diaryl carbonates such as diphenyl carbonate and ditolyl carbonate; dialkyl carbonates such as dimethyl carbonate and diethyl carbonate; biscarbonate bodies of dihydroxy compounds, monocarbonate bodies of dihydroxy compounds, and cyclic carbonates. And carbonate bodies of dihydroxy compounds such as

  The method for producing the polycarbonate resin is not particularly limited, and any method can be adopted. Examples thereof include an interfacial polymerization method, a melt transesterification method, a pyridine method, a ring-opening polymerization method of a cyclic carbonate compound, and a solid phase transesterification method of a prepolymer. Hereinafter, the interfacial polymerization method and the melt transesterification method, which are particularly suitable among these methods, will be specifically described.

(Interfacial polymerization method)
In the interfacial polymerization method, a dihydroxy compound and a carbonate precursor (preferably phosgene) are reacted in the presence of an organic solvent inert to the reaction and an aqueous alkaline solution, usually at a pH of 9 or higher. Polycarbonate resin is obtained by interfacial polymerization in the presence. In the reaction system, a molecular weight adjusting agent (terminal terminator) may be present as necessary, or an antioxidant may be present to prevent the oxidation of the dihydroxy compound.

  The dihydroxy compound and the carbonate precursor are as described above. Of the carbonate precursors, phosgene is preferably used, and a method using phosgene is particularly called a phosgene method.

  Examples of the organic solvent inert to the reaction include chlorinated hydrocarbons such as dichloromethane, 1,2-dichloroethane, chloroform, monochlorobenzene and dichlorobenzene; aromatic hydrocarbons such as benzene, toluene and xylene. . In addition, 1 type may be used for an organic solvent and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the alkali compound contained in the alkaline aqueous solution include alkali metal compounds and alkaline earth metal compounds such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and sodium hydrogen carbonate, among which sodium hydroxide and water Potassium oxide is preferred. In addition, 1 type may be used for an alkali compound and it may use 2 or more types together by arbitrary combinations and a ratio.

  Although there is no restriction | limiting in the density | concentration of the alkali compound in aqueous alkali solution, Usually, in order to control pH in the aqueous alkali solution of reaction to 10-12, it is used at 5 to 10 weight%. For example, when phosgene is blown, the molar ratio of the bisphenol compound and the alkali compound is usually 1: 1.9 or more in order to control the pH of the aqueous phase to be 10 to 12, preferably 10 to 11. Among these, it is preferable that the ratio is 1: 2.0 or more, usually 1: 3.2 or less, and more preferably 1: 2.5 or less.

Examples of the polymerization catalyst include aliphatic tertiary amines such as trimethylamine, triethylamine, tributylamine, tripropylamine, and trihexylamine; alicyclic rings such as N, N′-dimethylcyclohexylamine and N, N′-diethylcyclohexylamine. Tertiary amines of formula; aromatic tertiary amines such as N, N′-dimethylaniline and N, N′-diethylaniline; quaternary ammonium salts such as trimethylbenzylammonium chloride, tetramethylammonium chloride and triethylbenzylammonium chloride; Examples include pyridine, guanine, guanidine salts, and the like. In addition, 1 type may be used for a polymerization catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  Examples of the molecular weight modifier include aromatic phenols having a monovalent phenolic hydroxyl group; aliphatic alcohols such as methanol and butanol, mercaptans, and phthalimides, among which aromatic phenols are preferred. Specific examples of such aromatic phenols include alkyl groups such as m-methylphenol, p-methylphenol, m-propylphenol, p-propylphenol, p-tert-butylphenol, and p-long chain alkyl-substituted phenol. Substituted phenols: Vinyl group-containing phenols such as isopropanyl phenol, epoxy group-containing phenols, carboxyl group-containing phenols such as o-oxine benzoic acid, 2-methyl-6-hydroxyphenylacetic acid, and the like. In addition, a molecular weight regulator may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The usage-amount of a molecular weight modifier is 0.5 mol or more normally with respect to 100 mol of dihydroxy compounds, Preferably it is 1 mol or more, and is 50 mol or less normally, Preferably it is 30 mol or less. By making the usage-amount of a molecular weight modifier into this range, the thermal stability and hydrolysis resistance of a polycarbonate resin composition can be improved.

  In the reaction, the order of mixing the reaction substrate, reaction medium, catalyst, additive and the like is arbitrary as long as a desired polycarbonate resin is obtained, and an appropriate order may be arbitrarily set. For example, when phosgene is used as the carbonate precursor, the molecular weight regulator can be mixed at any time as long as it is between the reaction (phosgenation) of the dihydroxy compound and phosgene and the start of the polymerization reaction. In addition, reaction temperature is 0-40 degreeC normally, and reaction time is normally several minutes (for example, 10 minutes)-several hours (for example, 6 hours).

(Melted ester exchange method)
In the melt transesterification method, for example, a transesterification reaction between a carbonic acid diester and a dihydroxy compound is performed.

  The dihydroxy compound is as described above. On the other hand, examples of the carbonic acid diester include dialkyl carbonate compounds such as dimethyl carbonate, diethyl carbonate, and di-tert-butyl carbonate; diphenyl carbonate; substituted diphenyl carbonate such as ditolyl carbonate, and the like. Of these, diphenyl carbonate and substituted diphenyl carbonate are preferable, and diphenyl carbonate is particularly preferable. In addition, carbonic acid diester may use 1 type and may use 2 or more types together by arbitrary combinations and a ratio.

  The ratio of the dihydroxy compound and the carbonic acid diester is arbitrary as long as the desired polycarbonate resin can be obtained, but it is preferable to use an equimolar amount or more of the carbonic acid diester with respect to 1 mol of the dihydroxy compound. Is more preferable. The upper limit is usually 1.30 mol or less. By setting it as such a range, the amount of terminal hydroxyl groups can be adjusted to a suitable range.

In the polycarbonate resin, the amount of terminal hydroxyl groups tends to have a great influence on thermal stability, hydrolysis stability, color tone and the like. For this reason, you may adjust the amount of terminal hydroxyl groups as needed by a well-known arbitrary method. In the transesterification reaction, a polycarbonate resin in which the terminal hydroxyl group amount is adjusted can be usually obtained by adjusting the mixing ratio of the carbonic acid diester and the aromatic dihydroxy compound, the degree of vacuum during the transesterification reaction, and the like. In addition, the molecular weight of the polycarbonate resin usually obtained can also be adjusted by this operation.

  When adjusting the amount of terminal hydroxyl groups by adjusting the mixing ratio of the carbonic acid diester and the dihydroxy compound, the mixing ratio is as described above. Further, as a more aggressive adjustment method, there may be mentioned a method in which a terminal terminator is mixed separately during the reaction. Examples of the terminal terminator at this time include monohydric phenols, monovalent carboxylic acids, carbonic acid diesters, and the like. In addition, 1 type may be used for a terminal terminator and it may use 2 or more types together by arbitrary combinations and a ratio.

  When producing a polycarbonate resin by the melt transesterification method, a transesterification catalyst is usually used. Any transesterification catalyst can be used. Among them, it is preferable to use, for example, an alkali metal compound and / or an alkaline earth metal compound. In addition, auxiliary compounds such as basic boron compounds, basic phosphorus compounds, basic ammonium compounds, and amine compounds may be used in combination. In addition, 1 type may be used for a transesterification catalyst and it may use 2 or more types together by arbitrary combinations and a ratio.

  In the melt transesterification method, the reaction temperature is usually 100 to 320 ° C. The pressure during the reaction is usually a reduced pressure condition of 2 mmHg or less. As a specific operation, a melt polycondensation reaction may be performed under the above-mentioned conditions while removing a by-product such as an aromatic hydroxy compound.

  The melt polycondensation reaction can be performed by either a batch method or a continuous method. When performing by a batch type, the order which mixes a reaction substrate, a reaction medium, a catalyst, an additive, etc. is arbitrary as long as a desired aromatic polycarbonate resin is obtained, What is necessary is just to set an appropriate order arbitrarily. However, considering the stability of the polycarbonate resin and the polycarbonate resin composition, the melt polycondensation reaction is preferably carried out continuously.

  In the melt transesterification method, a catalyst deactivator may be used as necessary. As the catalyst deactivator, a compound that neutralizes the transesterification catalyst can be arbitrarily used. Examples thereof include sulfur-containing acidic compounds and derivatives thereof. In addition, 1 type may be used for a catalyst deactivator and it may use 2 or more types together by arbitrary combinations and a ratio.

  The amount of the catalyst deactivator used is usually 0.5 equivalents or more, preferably 1 equivalent or more, and usually 10 equivalents or less, relative to the alkali metal or alkaline earth metal contained in the transesterification catalyst. Preferably it is 5 equivalents or less. Furthermore, it is 1 ppm or more normally with respect to aromatic polycarbonate resin, and is 100 ppm or less normally, Preferably it is 20 ppm or less.

  The molecular weight of the polycarbonate resin is arbitrary and may be appropriately selected and determined. The viscosity average molecular weight [Mv] converted from the solution viscosity is usually 10,000 or more, preferably 16,000 or more, more preferably 18, 000 or more, and usually 40,000 or less, preferably 30,000 or less. By setting the viscosity average molecular weight to be equal to or higher than the lower limit of the above range, the mechanical strength of the polycarbonate resin composition of the present invention can be further improved, which is more preferable when used for applications requiring high mechanical strength. On the other hand, by setting the viscosity average molecular weight to be equal to or lower than the upper limit of the above range, the polycarbonate resin composition of the present invention can be suppressed and improved in fluidity, and the molding processability can be improved and the molding process can be easily performed. Two or more types of polycarbonate resins having different viscosity average molecular weights may be mixed and used, and in this case, a polycarbonate resin having a viscosity average molecular weight outside the above-mentioned preferred range may be mixed.

The viscosity average molecular weight [Mv] is obtained by using methylene chloride as a solvent and obtaining an intrinsic viscosity [η] (unit: dl / g) at a temperature of 20 ° C. using an Ubbelohde viscometer. , Η = 1.23 × 10 ⁻⁴ Mv ^0.83 . The intrinsic viscosity [η] is a value calculated from the following formula by measuring the specific viscosity [η _sp ] at each solution concentration [C] (g / dl).

  The terminal hydroxyl group concentration of the polycarbonate resin is arbitrary and may be appropriately selected and determined, but is usually 1,000 ppm or less, preferably 800 ppm or less, more preferably 600 ppm or less. Thereby, the residence heat stability and color tone of the polycarbonate resin composition of the present invention can be further improved. Moreover, the minimum is 10 ppm or more normally, Preferably it is 30 ppm or more, More preferably, it is 40 ppm or more. Thereby, the fall of molecular weight can be suppressed and the mechanical characteristic of the polycarbonate resin composition of this invention can be improved more. The unit of the terminal hydroxyl group concentration is the weight of the terminal hydroxyl group expressed in ppm relative to the weight of the polycarbonate resin. The measurement method is colorimetric determination (method described in Macromol. Chem. 88 215 (1965)) by the titanium tetrachloride / acetic acid method.

  A polycarbonate resin may be used individually by 1 type, and may use 2 or more types together by arbitrary combinations and a ratio.

  The polycarbonate resin is a polycarbonate resin alone (the polycarbonate resin alone is not limited to an embodiment containing only one type of polycarbonate resin, and is used in a sense including an embodiment containing a plurality of types of polycarbonate resins having different monomer compositions and molecular weights, for example. .), Or an alloy (mixture) of a polycarbonate resin and another thermoplastic resin may be used in combination. Further, for example, for the purpose of further improving flame retardancy and impact resistance, a polycarbonate resin is copolymerized with an oligomer or polymer having a siloxane structure; for the purpose of further improving thermal oxidation stability and flame retardancy A monomer, oligomer or polymer having a copolymer; a monomer, oligomer or polymer having a dihydroxyanthraquinone structure for the purpose of improving thermal oxidation stability; Copolymers with oligomers or polymers having an olefin-based structure; for the purpose of improving chemical resistance, they may be configured as copolymers mainly composed of polycarbonate resins, such as copolymers with polyester resin oligomers or polymers. . When used in combination with other thermoplastic resins, the proportion of the polycarbonate resin in the resin component is preferably 50% by weight or more, more preferably 60% by weight, and further preferably 70% by weight or more. preferable.

  Further, in order to improve the appearance of the molded product and improve the fluidity, the polycarbonate resin may contain a polycarbonate oligomer. The viscosity average molecular weight [Mv] of this polycarbonate oligomer is usually 1,500 or more, preferably 2,000 or more, and usually 9,500 or less, preferably 9,000 or less. Furthermore, the polycarbonate ligomer contained is preferably 30% by weight or less of the polycarbonate resin (including the polycarbonate oligomer).

Further, the polycarbonate resin may be not only a virgin raw material but also a polycarbonate resin regenerated from a used product (so-called material-recycled polycarbonate resin). Examples of the used products include: optical recording media such as optical disks; light guide plates; vehicle window glass, vehicle headlamp lenses, windshields and other vehicle transparent members; water bottles and other containers; eyeglass lenses; Examples include architectural members such as glass windows and corrugated sheets. Also, non-conforming products, pulverized products obtained from sprues, runners, etc., or pellets obtained by melting them can be used.

  However, the regenerated polycarbonate resin is preferably 80% by weight or less, more preferably 50% by weight or less, among the polycarbonate resins contained in the polycarbonate resin composition of the present invention. Recycled polycarbonate resin is likely to have undergone deterioration such as heat deterioration and aging deterioration, so when such polycarbonate resin is used more than the above range, hue and mechanical properties can be reduced. It is because there is sex.

  The above-mentioned transparent material can contain various known additives as necessary within a range not impairing the characteristics of the present invention. For example, heat stabilizer, antioxidant, mold release agent, flame retardant, flame retardant aid, UV absorber, lubricant, light stabilizer, plasticizer, antistatic agent, thermal conductivity improver, conductivity improver, Coloring agents, impact resistance improving agents, antibacterial agents, chemical resistance improving agents, reinforcing agents, laser marking improving agents, refractive index adjusting agents and the like can be mentioned. The specific kind and amount of these additives can be selected from known suitable materials for transparent materials.

  Here, it illustrates about the preferable additive mix | blended with polycarbonate resin.

  Examples of the heat stabilizer include phosphorus compounds. Any known phosphorous compound can be used. Specific examples include phosphorus oxo acids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; acidic pyrophosphate metal salts such as acidic sodium pyrophosphate, acidic potassium pyrophosphate, and acidic calcium pyrophosphate; phosphoric acid Examples thereof include phosphates of Group 1 or Group 10 metals such as potassium, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds.

  Among them, triphenyl phosphite, tris (monononylphenyl) phosphite, tris (monononyl / dinonyl phenyl) phosphite, tris (2,4-di-tert-butylphenyl) phosphite, monooctyl diphenyl phosphite, Dioctyl monophenyl phosphite, monodecyl diphenyl phosphite, didecyl monophenyl phosphite, tridecyl phosphite, trilauryl phosphite, tristearyl phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) ) Organic phosphites such as octyl phosphite are preferred.

  The content of the heat stabilizer is usually 0.001 parts by weight or more, preferably 0.001 parts by weight or more, more preferably 0.01 parts by weight or more with respect to 100 parts by weight of the polycarbonate resin. It is not more than parts by weight, preferably not more than 0.5 parts by weight, more preferably not more than 0.3 parts by weight, still more preferably not more than 0.1 parts by weight. If the amount of the heat stabilizer is too small, it is difficult to obtain the effect of improving the heat stability. If the amount is too large, the heat stability may be lowered.

  As antioxidant, a hindered phenolic antioxidant is mentioned, for example. Specific examples thereof include pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl). ) Propionate, thiodiethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N′-hexane-1,6-diylbis [3- (3,5-di-) tert-butyl-4-hydroxyphenylpropionamide), 2,4-dimethyl-6- (1-methylpentadecyl) phenol, diethyl [[3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl ] Methyl] phosphoate, 3,3 ′, 3 ″, 5,5 ′, 5 ″ -hexa-tert-butyl-a, a ′, ''-(Mesitylene-2,4,6-triyl) tri-p-cresol, 4,6-bis (octylthiomethyl) -o-cresol, ethylenebis (oxyethylene) bis [3- (5-tert- Butyl-4-hydroxy-m-tolyl) propionate], hexamethylenebis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 1,3,5-tris (3,5- Di-tert-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione, 2,6-di-tert-butyl-4- (4 6-bis (octylthio) -1,3,5-triazin-2-ylamino) phenol and the like.

  Among them, pentaerythritol tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate preferable.

  The content of the antioxidant is usually 0.001 part by weight or more, preferably 0.01 part by weight or more, and usually 1 part by weight or less, preferably 0.5 part by weight with respect to 100 parts by weight of the polycarbonate resin. Part or less, more preferably 0.3 part by weight or less. When the content of the antioxidant is less than or equal to the lower limit of the range, the effect as an antioxidant may be insufficient, and when the content of the antioxidant exceeds the upper limit of the range, There is a possibility that the effect reaches its peak and is not economical.

  Examples of the release agent include aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, polysiloxane silicone oils, and the like.

  Examples of the aliphatic carboxylic acid include saturated or unsaturated aliphatic monovalent, divalent or trivalent carboxylic acid. Here, the aliphatic carboxylic acid includes alicyclic carboxylic acid. Among these, preferable aliphatic carboxylic acids are monovalent or divalent carboxylic acids having 6 to 36 carbon atoms, and aliphatic saturated monovalent carboxylic acids having 6 to 36 carbon atoms are more preferable. Specific examples of such aliphatic carboxylic acids include palmitic acid, stearic acid, caproic acid, capric acid, lauric acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, mellicic acid, tetrariacontanoic acid, montanic acid, adipine Examples include acids and azelaic acid.

  As aliphatic carboxylic acid in ester of aliphatic carboxylic acid and alcohol, the same thing as the said aliphatic carboxylic acid can be used, for example. On the other hand, examples of the alcohol include saturated or unsaturated monohydric or polyhydric alcohols. These alcohols may have a substituent such as a fluorine atom or an aryl group. Among these, a monovalent or polyvalent saturated alcohol having 30 or less carbon atoms is preferable, and an aliphatic or alicyclic saturated monohydric alcohol or aliphatic saturated polyhydric alcohol having 30 or less carbon atoms is more preferable.

  Specific examples of such alcohols include octanol, decanol, dodecanol, stearyl alcohol, behenyl alcohol, ethylene glycol, diethylene glycol, glycerin, pentaerythritol, 2,2-dihydroxyperfluoropropanol, neopentylene glycol, ditrimethylolpropane, dipentaerythritol, and the like. Is mentioned.

Specific examples of esters of aliphatic carboxylic acids and alcohols include beeswax (a mixture based on myricyl palmitate), stearyl stearate, behenyl behenate, stearyl behenate, glycerin monopalmitate, glycerin monostearate Examples thereof include rate, glycerol distearate, glycerol tristearate, pentaerythritol monopalmitate, pentaerythritol monostearate, pentaerythritol distearate, pentaerythritol tristearate, pentaerythritol tetrastearate and the like.

  Examples of the aliphatic hydrocarbon compound having a number average molecular weight of 200 to 15,000 include liquid paraffin, paraffin wax, microwax, polyethylene wax, Fischer-Tropsch wax, and α-olefin oligomer having 3 to 12 carbon atoms. . Here, the aliphatic hydrocarbon includes alicyclic hydrocarbons.

  Among these, paraffin wax, polyethylene wax, or a partial oxide of polyethylene wax is preferable, and paraffin wax and polyethylene wax are more preferable.

  The number average molecular weight of the aliphatic hydrocarbon is preferably 5,000 or less.

  Examples of the polysiloxane silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, diphenyl silicone oil, and fluorinated alkyl silicone.

  The content of the release agent is usually 0.001 part by weight or more, preferably 0.01 part by weight or more, and usually 5 parts by weight or less, preferably 3 parts by weight or less, relative to 100 parts by weight of the polycarbonate resin. More preferably, it is 1 part by weight or less, and still more preferably 0.5 part by weight or less. When the content of the release agent is not more than the lower limit of the above range, the effect of releasability may not be sufficient, and when the content of the release agent exceeds the upper limit of the above range, hydrolysis resistance And mold contamination during injection molding may occur.

  Examples of the flame retardant include halogen-based, phosphorus-based, organic acid metal salt-based, and silicone-based flame retardants, and examples of the flame retardant auxiliary include fluororesin-based flame retardant auxiliary. A flame retardant and a flame retardant aid can be used in combination, or a plurality of flame retardants can be used in combination. Among these, phosphorus flame retardants, organic acid metal salt flame retardants, and fluororesin flame retardant aids are preferred.

  Examples of phosphorus flame retardants include aromatic phosphate esters and phosphazene compounds. As the organic acid metal salt flame retardant, an organic sulfonic acid metal salt is preferable, and a fluorine-containing organic sulfonic acid metal salt is particularly preferable. Specific examples thereof include potassium perfluorobutane sulfonate. As the fluorine-based flame retardant aid, a fluoroolefin resin is preferable, and a tetrafluoroethylene resin having a fibril structure can be exemplified. The fluorine-based flame retardant aid may be in a powder form, a dispersion form, a powder form in which a fluororesin is coated with another resin, or any form.

  The blending ratio of these flame retardants and flame retardant aids may be blended in the amount necessary to achieve the desired flame retardant level, but is usually in the case of phosphorus flame retardants relative to 100 parts by weight of polycarbonate. It is preferably blended in the range of 1 to 20 parts by weight, in the case of organic acid metal salts in the range of 0.01 to 1 parts by weight, and in the case of fluororesin-based flame retardant aids in the range of 0.01 to 1 part by weight. . Within the above range, one or more flame retardants and flame retardant aids can be used. If the amount is less than this range, it is difficult to improve the flame retardancy. If the amount is more than this range, the thermal stability and mechanical properties tend to decrease, which is not preferable. The flame retardant level can be determined by, for example, a combustion test typified by UL94.

  Examples of ultraviolet absorbers include inorganic ultraviolet absorbers such as cerium oxide and zinc oxide; organics such as benzotriazole compounds, benzophenone compounds, salicylate compounds, cyanoacrylate compounds, triazine compounds, oxanilide compounds, malonic ester compounds, and hindered amine compounds. Examples include ultraviolet absorbers. Of these, organic ultraviolet absorbers are preferred, and benzotriazole compounds are more preferred. By selecting an organic ultraviolet absorber, the polycarbonate resin composition of the present invention tends to have good transparency and mechanical properties.

  Specific examples of the benzotriazole compound include, for example, 2- (2′-hydroxy-5′-methylphenyl) benzotriazole, 2- [2′-hydroxy-3 ′, 5′-bis (α, α-dimethylbenzyl). ) Phenyl] -benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-tert-butyl-phenyl) -benzotriazole, 2- (2′-hydroxy-3′-tert-butyl-5 ′) -Methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butyl-phenyl) -5-chlorobenzotriazole), 2- (2'-hydroxy-3 ', 5'-di-tert-amyl) -benzotriazole, 2- (2'-hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] and the like, among others, 2- (2′- Hydroxy-5'-tert-octylphenyl) benzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2N-benzotriazol-2-yl) phenol] And 2- (2′-hydroxy-5′-tert-octylphenyl) benzotriazole is particularly preferable.

  Specific examples of such benzotriazole compounds include “Seesorb 701”, “Seesorb 702”, “Seesorb 703”, “Seesorb 704”, and “Seesorb 705” manufactured by Sipro Kasei Co., Ltd. (trade names, the same applies hereinafter). , “Seasorb 709”, “Biosorb 520”, “Biosorb 580”, “Biosorb 582”, “Biosorb 583” manufactured by Kyodo Yakuhin Co., Ltd. “UV5411”, “LA-32”, “LA-38”, “LA-36”, “LA-34”, “LA-31”, manufactured by Adeka, Inc. 234 "," Tinubin 326 "," Tinubin 327 "," Tinubin 3 8 ", and the like.

  The preferable content of the ultraviolet absorber is 0.01 parts by weight or more, more preferably 0.1 parts by weight or more, and 5 parts by weight or less, preferably 3 parts by weight or less with respect to 100 parts by weight of the polycarbonate resin. More preferably, it is 1 part by weight or less, and still more preferably 0.5 part by weight or less. If the content of the UV absorber is below the lower limit of the above range, the effect of improving the weather resistance may be insufficient, and if the content of the UV absorber exceeds the upper limit of the above range, the mold Debogit etc. may occur and cause mold contamination. In addition, 1 type may contain the ultraviolet absorber and 2 or more types may contain it by arbitrary combinations and a ratio.

Next, the silicone resin will be described in detail.
Although there is no restriction | limiting in particular as a silicone resin used for this embodiment, The loss of light is so preferable that there is little absorption in visible light, and it is preferable. In addition, a liquid silicone resin or the like is preferable in terms of mixing with a phosphor and processability to a wavelength conversion member. Especially in the liquid silicone resin, using an addition curing type that cures by hydrosilylation reaction, no by-product is generated at the time of curing, and there is no problem that the pressure in the mold does not become abnormally high, This is particularly preferable because sink marks and bubbles are hardly generated in the molded product, and further, since the curing speed is high, the molding cycle can be shortened.
The addition curing type liquid silicone resin contains an organopolysiloxane having a hydrosilyl group (first component), an organopolysiloxane having an alkenyl group (second component), and a curing catalyst.

  A typical example of the first component is a polydiorganosiloxane having two or more hydrosilyl groups in the molecule, specifically, a polydiorganosiloxane having hydrosilyl groups at both ends, and a polypolyorganosiloxane having both ends blocked with trimethylsilyl groups. Examples thereof include methylhydrosiloxane, methylhydrosiloxane-dimethylsiloxane copolymer, and the like. As the second component, those having at least two vinyl groups bonded to silicon atoms in one molecule are preferably used. An organopolysiloxane that serves both as the first component and the second component, that is, an organopolysiloxane having both a hydrosilyl group and an alkenyl group in one molecule may be used. Further, the first component and the second component may be used alone, or two or more kinds of the first component and / or the second component may be used in combination.

  The curing catalyst is a catalyst for promoting the addition reaction between the hydrosilyl group in the first component and the alkenyl group in the second component. Examples thereof include platinum black, second platinum chloride, chloroplatinic acid, chloride. Platinum group metal catalysts such as a reaction product of platinum acid and a monohydric alcohol, a complex of chloroplatinic acid and olefins, a platinum-based catalyst such as platinum bisacetoacetate, a palladium-based catalyst, and a rhodium-based catalyst. A curing catalyst may be used independently and may use 2 or more types together.

Furthermore, fumed silica can be added to the silicone resin for the purpose of imparting thixotropic properties to the raw material composition.
Fumed silica is an ultrafine particle having a large specific surface area of 50 m ² / g or more. Examples of commercially available fumed silica include Aerosil (registered trademark) of Nippon Aerosil Co., Ltd., WACKER HDK of Asahi Kasei Wacker Silicone Co., Ltd. ( Registered trademark). Giving thixotropy is effective in preventing the composition of the raw material composition from becoming non-uniform due to the precipitation of the phosphor.
In particular, when hydrophobic fumed silica whose surface is modified with a trimethylsilyl group, a dimethylsilyl group, a dimethylsilicone chain, or the like is used, thixotropic properties can be imparted to the raw material composition without causing excessive thickening. In other words, a raw material composition having both high fluidity suitable for injection molding and an anti-settling effect of the phosphor can be obtained.
Although there is no restriction | limiting in particular in the addition amount of a fumed silica, Usually 0.1 weight part or more with respect to 100 weight part of silicone resins, Preferably it is 0.5 weight part or more, Especially preferably, it is 1 weight part or more, Usually 20 It is not more than parts by weight, preferably not more than 18 parts by weight, particularly preferably not more than 15 parts by weight. If the amount is less than 0.1 parts by weight, high fluidity suitable for injection molding and the effect of preventing the settling of the phosphor cannot be sufficiently obtained. It is not preferable because the properties cannot be obtained.
In addition, as necessary, the raw material composition is a curing rate control agent, anti-aging agent, radical inhibitor, ultraviolet absorber, adhesion improver, flame retardant, surfactant, storage stability improver, ozone deterioration prevention. Additives such as an agent, a light stabilizer, a plasticizer, a coupling agent, an antioxidant, a heat stabilizer, an antistatic agent, and a release agent can be added.

  In addition, the phosphor composition may contain a known phosphor or a diffusion material. When a diffusing material is contained as another component, it is preferable to contain an inorganic light diffusing material, an organic light diffusing material, or bubbles.

As the inorganic light diffusing material, for example, inorganic light diffusing materials such as silicon, aluminum, titanium, zirconium, calcium, and barium can be used, and the group consisting of silicon, aluminum, titanium, and zirconium can be used. It is preferable to use an inorganic light diffusing material containing at least one element. As the organic light diffusing material, it is possible to use an acrylic light diffusing material, or an organic light diffusing material containing silicon as an element, or an organic material containing silicon as an element. It is preferable to use a system light diffusing material.

  Specific examples of inorganic light diffusing materials include silicon dioxide (silica), white carbon, talc, magnesium oxide, zinc oxide, titanium oxide, aluminum oxide, zirconium oxide, boron oxide, calcium carbonate, barium carbonate, magnesium carbonate, water Examples of the material include aluminum oxide, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, barium sulfate, calcium silicate, magnesium silicate, aluminum silicate, sodium aluminosilicate, zinc silicate, glass, and mica.

  Examples of the organic light diffusing material include materials such as a styrene (co) polymer, an acrylic (co) polymer, a siloxane (co) polymer, and a polyamide (co) polymer. Some or all of these molecules of the organic diffusing material may or may not be cross-linked. Here, “(co) polymer” means both “polymer” and “copolymer”.

  Among the materials described above, in order to increase the light diffusion effect with a small amount, it is preferable to select a material having a large difference between the refractive index of the transparent material and the refractive index of the selected diffusing material. In order not to greatly reduce the luminous efficiency, it is preferable to select a material having high transparency.

  For example, when the transparent material is a polycarbonate resin, the diffusing agent may be a crosslinked acrylic (co) polymer particle, a crosslinked particle of a copolymer of an acrylic compound and a styrene compound, a siloxane (co) polymer particle, an acrylic It is preferable to use hybrid crosslinked particles of a compound and a compound containing a silicon atom, and it is more preferable to use crosslinked acrylic (co) polymer particles and siloxane (co) polymer particles.

  As the crosslinked acrylic (co) polymer particles, polymer particles composed of a non-crosslinkable acrylic monomer and a crosslinkable monomer are more preferable, and polymer particles obtained by crosslinking methyl methacrylate and trimethylolpropane tri (meth) acrylate are more preferable. . As the siloxane-based (co) polymer, polyorganosilsesquioxane particles are more preferable, and polymethylsilsesquioxane particles are more preferable.

  In the present invention, polymethylsilsesquioxane particles are particularly preferable in terms of excellent thermal stability.

  The dispersion shape of the diffusing material in the wavelength conversion member may be substantially spherical, plate-like, needle-like, or indefinite, but is preferably substantially spherical in that there is no anisotropy in the light scattering effect. The average dimension of the diffusing material is usually 100 μm or less, preferably 30 μm or less, more preferably 10 μm or less, and usually 0.01 μm or more, preferably 0.1 μm or more. If the average size of the diffusing material is out of the above range, the light diffusivity is likely to fluctuate greatly due to subtle differences in the content of the diffusing material and the difference in particle size, and the light diffusing property should be controlled stably May become difficult, and it may be difficult to exhibit sufficient light diffusibility required in the present invention. As a result, it may become difficult to stably control the wavelength conversion efficiency within a preferable range. Here, the average dimension of the diffusing material is a 50% average dimension based on volume, and is the value of the median diameter (D50) of the volume standard particle size distribution measured by laser or diffraction scattering method.

In addition, the particle size distribution of the diffusing material may be a monodispersed system or a polydispersed system having several peak tops. However, it is preferable that the particle size distribution is narrow and the particle size is almost a single particle size (monodispersion or particle size distribution close to monodispersion).

As an index indicating the degree of distribution of the particle size of the diffusing material, there is a ratio (D _v / D _n ) between the volume-based average particle size D _v and the number-based average particle size D _n of the diffusing material. In the present _invention, it is preferred D v / _{D n} is 1.0 or more. On the other _hand, it is preferred D v / _{D n} is 5 or less. If D _v / D _n is too large, there will be a diffusing material having a significantly different weight, and the dispersion of the diffusing material tends to be non-uniform in the wavelength conversion member.

  The inorganic light diffusing material, the organic light diffusing material, and the bubbles used as the diffusing material described above may be used singly or in combination of two or more kinds having different materials and dimensions. When two or more types are used in combination, the refractive index of the diffusing material is calculated by the volume average of a plurality of diffusing materials.

The refractive index of the diffusing material is preferably 1.0 or more and 1.9 or less. The diffusing material preferably has high transparency and excellent light transmittance. For example, the extinction coefficient may be 10 ⁻² or less, preferably 10 ⁻³ or less, and more preferably 10 ^{−. 4} or less, particularly preferably 10 ⁻⁶ or less. The refractive index of the diffusing material can be measured by the immersion method (Aerosol Research Vol. 9, No. 1 Spring pp. 44-50 (1994)) of YOSHIYAMA et al. The measurement temperature is 20 ° C., and the measurement wavelength is 450 nm.

  Table 2 below lists the refractive indices of materials commonly used as diffusing materials. In addition, the refractive index of each material in Table 2 is a general reference value, and the refractive index of each material is not necessarily limited to the value in Table 2.

  The content of the diffusing material in the wavelength conversion member depends on the type of transparent material. For example, when the transparent material is a polycarbonate resin and the diffusing material is polymethylsilsesquioxane particles, the content is 100 parts by weight of the polycarbonate resin. On the other hand, it is usually 0.1 parts by weight or more, preferably 0.3 parts by weight or more, more preferably 0.5 parts by weight or more, and usually 10.0 parts by weight or less, preferably 7.0 parts by weight or less. More preferably, it is 3.0 parts by weight or less. If the content of the diffusing material is too small, the diffusing effect is insufficient, and if it is too large, the mechanical identification may decrease, which is not preferable.

  The manufacturing method of the phosphor composition and the processing method of the wavelength conversion member are not particularly limited, and a known method may be used as a processing method of the transparent material. For example, when the transparent material is a polycarbonate resin, a general method for producing a resin composition is as follows.

  A phosphor, a diffusing material, and other components blended as necessary are added to the polycarbonate resin and mixed with various mixers such as a tumbler mixer and a Henschel mixer. Mixing may be performed by mixing all raw materials at once, or by dividing several raw materials and mixing them. Thereafter, it is melt-kneaded with a Banbury mixer, roll, Brabender, single-screw kneading extruder, twin-screw kneading extruder, kneader or the like to obtain resin composition pellets.

  In the case where the transparent material is a polycarbonate resin, and the case where the diffusing material is other than bubbles, preferable conditions are illustrated in more detail.

  A polycarbonate resin, a phosphor, a diffusing material, and other additives are mixed with a tumbler mixer, and then melt-kneaded using a single screw or twin screw extruder. As a melt-kneading condition, a screw composed mainly of a forward-flight flight screw element is used as a screw so as not to apply excessive pruning force. The frequent use of a screw element that strongly applies a cutting force, such as a reverse feed flight screw or a kneading screw element, is undesirable because it causes discoloration of the resin. In addition, when the phosphor is hard, it is preferable to use a screw and cylinder made of a material that has been subjected to an abrasion-resistant treatment that is difficult to cut.

  The kneading temperature is preferably in the range of 230 to 340 ° C. If the measured resin temperature exceeds 340 ° C., discoloration tends to occur, which is not preferable. If the resin temperature is less than 230 ° C., the melt viscosity of the polycarbonate resin is too high, and the mechanical load on the extruder increases. A particularly preferable kneading temperature is in the range of 240 to 300 ° C.

  What is necessary is just to select a screw rotation speed and discharge amount suitably in view of the production speed, the load to an extruder, and the state of a resin pellet. Moreover, it is preferable to install one or more vent structures in the extruder for releasing air entrained with the raw material and gas generated by heating out of the extruder system.

  What is necessary is just to shape | mold and process into a desired shape by arbitrary processing methods using the polycarbonate resin composition pellet obtained by the above.

  The method for forming the phosphor composition is not particularly limited, and may be formed by a known method according to the required specifications. Examples thereof include sheet / film extrusion molding, profile extrusion molding, vacuum molding, injection molding, blow molding, injection blow molding, rotational molding, foam molding, and the like. Among these, it is preferable to adopt an injection molding method. Furthermore, if necessary, the molded body can be further processed by welding, bonding, cutting, and the like. When the diffusing material is a bubble, the bubble may be formed in the member by a method such as blending of a blowing agent, nitrogen gas injection, supercritical gas injection, or the like.

In addition, the wavelength conversion member may be an embodiment of a wavelength conversion member composed only of the phosphor composition, or may be formed by applying the phosphor composition on a transparent substrate such as glass or an acrylic plate, and may be used as the wavelength conversion member. .
Hereinafter, the structure of the light emitting device according to the embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic view of a light emitting device according to an embodiment of the present invention.
The light emitting device 10 includes at least a blue semiconductor light emitting element 1 and a wavelength conversion member 3 as its constituent members. The blue semiconductor light emitting element 1 emits excitation light for exciting the phosphor contained in the wavelength conversion member 3.
The blue semiconductor light emitting element 1 usually emits excitation light having a peak wavelength of 425 nm to 475 nm, and preferably emits excitation light having a peak wavelength of 440 nm to 460 nm. The number of blue semiconductor light emitting elements 1 can be appropriately set depending on the intensity of excitation light required by the apparatus.

The blue semiconductor light emitting element 1 is mounted on the chip mounting surface 2 a of the wiring board 2. A wiring pattern (not shown) for supplying electrodes to these blue semiconductor light emitting elements 1 is formed on the wiring substrate 2 to constitute an electric circuit.
It is preferable that the wiring board 2 is excellent in electrical insulation, has good heat dissipation, and has a high reflectance. The reflectance is preferably 80% or more. As such a wiring board, alumina ceramic, resin, glass epoxy, composite resin containing filler in resin, or the like can be used. From the viewpoint of improving the light reflectivity on the chip mounting surface 2a of the wiring board 2 and improving the light emission efficiency of the light emitting device 10, a silicone resin containing a white pigment such as alumina powder, silica powder, magnesium oxide, titanium oxide or the like is used. It is preferable to use it.

  The wavelength conversion member 3 converts the wavelength of a part of incident light emitted from the blue semiconductor light emitting element 1 and emits outgoing light having a wavelength different from that of the incident light. The wavelength conversion member 3 includes a yellow-green phosphor represented by the general formula (X), the general formula (1), or the general formula (2). As described above, these phosphors are uniformly dispersed in the resin. Examples of the resin in which the phosphor is dispersed include polycarbonate resin, polyester resin, acrylic resin, epoxy resin, and silicone resin. The wavelength conversion member 3 is obtained by molding a phosphor composition in which a yellow-green phosphor is dispersed in a transparent material such as a resin. It can also be obtained by forming the phosphor composition on a transparent substrate such as glass or an acrylic plate.

  Further, as described above, the wavelength conversion member 3 preferably contains a small amount of a diffusing material together with the phosphor.

  The wavelength conversion member 3 has a distance from the blue semiconductor light emitting element 1. There may be a gap between the wavelength conversion member 3 and the blue semiconductor light emitting element 1 or may be filled with a filler. Thus, by the aspect which has distance between the wavelength conversion member 3 and the blue semiconductor light-emitting device 1, deterioration of the phosphor contained in the wavelength conversion member 3 and the wavelength conversion member by the heat which the blue semiconductor light-emitting device 1 emits is suppressed. can do. The distance between the blue semiconductor light emitting element 1 and the wavelength conversion member 3 is preferably 10 μm or more, more preferably 100 μm or more, particularly preferably 1.0 mm or more, on the other hand, 1.0 m or less, more preferably 500 mm or less, 100 mm or less is particularly preferable.

EXAMPLES Next, although an Example and a comparative example are given and this invention is demonstrated more concretely, this invention is not limited to a following example, unless the summary is exceeded.
Synthesis example 1
Synthetic phosphor of phosphor GYAG1 23.44 g of Y ₂ O ₃ , Al ₂ O so that the charged composition of each raw material is Y _2.91 Ce _0.09 Al _3.8 Ga _1.2 O _{12 3} for 137.04 g, Ga ₂ O ₃ for 79.56 g, CeO
After the BaF ₂ is 10.96g and flux ₂ was performed 27.6g each weighed sufficiently stirred and mixed, was packed in an alumina crucible. This was placed in a resistance heating type electric furnace equipped with a temperature controller, heated to 1450 ° C. in a hydrogen-containing nitrogen atmosphere, allowed to cool to room temperature, and subjected to the above-mentioned phosphor GAYG1 (average particle diameter of 15 μm) by sieving and hydrochloric acid washing treatment. )
Synthesis example 2
Synthetic phosphor of phosphor GYAG2 23.71 g of Y ₂ O ₃ and Al ₂ O so that the charged composition of each raw material of the phosphor becomes Y _2.91 Ce _0.09 Al _4.2 Ga _0.8 O _{12 3} is 155.56 g, Ga ₂ O ₃ is 54.47 g, CeO
_A phosphor GYAG2 (average particle size 15 μm) was obtained in the same manner as in Synthesis Example 1 except that 11.25 g of ₂ and 27.6 g of BaF ₂ as a flux were weighed.
Synthesis example 3
245.01 g of Y ₂ O ₃ , Al ₂ O so that the raw material composition of the synthetic phosphor of phosphor GYAG3 is Y _2.97 Ce _0.03 Al _4.2 Ga _0.8 O _{12 3} is 156.43 g, Ga ₂ O ₃ is 54.78 g, CeO
Except that the BaF ₂ is 3.77g and flux ₂ were weighed 27.6g, respectively, in the same manner as in Synthesis Example 1 to obtain a phosphor GYAG3 (average particle size 12 [mu] m).
Synthesis example 4
Mixing composition of the raw material of the synthetic phosphor of the phosphor GYAG4 is, so that the _{Y 2.94 Ce 0.06 Al 4 Ga 1} O 12, a Y ₂ O ₃ 238.62g, the Al ₂ O ₃ 146. 58 g, Ga ₂ O ₃ 67.37 g, CeO ₂ 7.
A phosphor GYAG4 (average particle size 11 μm) was obtained in the same manner as in Synthesis Example 1 except that 42 g and 27.6 g of BaF ₂ as a flux were each weighed.

Preparation composition of Ga or Ce and results of powder characteristics (relative to phosphors GYAG1 to 4 synthesized in Synthesis Examples 1 to 4 and YAG phosphor (Mitsubishi Chemical Corporation BY-102; average particle size 18 μm)) Table 3 summarizes luminance, emission peak, chromaticity, particle size, and excitation intensity of each wavelength when the excitation intensity of 450 nm is 100%.

(Powder emission characteristics evaluation method)
Using a spectrofluorophotometer F-4500 manufactured by Hitachi, relative luminance, emission peak, and chromaticity were determined for the phosphors of Synthesis Examples 1 to 4 and Comparative Example 1 as emission spectra at an excitation wavelength of 450 nm.
The relative luminance was the relative luminance of each phosphor when the luminance of the YAG phosphor of Comparative Example 1 was 100%.
(Powder particle size measurement method)
The particle size and weight median diameter d50 were measured with a laser diffraction particle size distribution measuring apparatus LA-300 manufactured by Horiba. Specifically, it is a value obtained from a frequency-based particle size distribution curve measured by a laser diffraction / scattering method in which a phosphor is dispersed in an aqueous solution.
(Excitation intensity at each wavelength when the excitation intensity at 450 nm is 100%)
Using a spectrofluorometer F-4500 manufactured by Hitachi, the excitation spectrum at the emission peak shown in Table 1 of each phosphor was measured, and the relative excitation intensity at 440 nm to 460 nm when the excitation intensity at 450 nm was taken as 100%. Calculated.
As shown in Table 3, the phosphors shown in Synthesis Examples 1 to 4 have an excitation spectrum intensity change of 4.0% or less of the excitation light spectrum intensity at 450 nm in the wavelength range of 440 to 460 nm, and 440 to 460 nm. A stable emission spectrum is obtained upon excitation.
(Method and method for preparing test piece for optical properties of phosphor-containing resin composition)
Each material (phosphor, additive, silicone resin) was weighed at a weight ratio shown in Table 4 so that the total weight was 10 g, and 3 at 1200 rpm at room temperature using a vacuum defoaming kneader V-mini300 manufactured by EME. Defoaming and kneading for minutes was carried out to obtain a phosphor-containing silicone resin composition.

得られたシリコーン樹脂組成物を２０ｍｍΦのガラス製バイアル瓶に厚み１ｍｍとなるよう注型し、１５０℃５分、続いて２００℃２０分加熱硬化することで、蛍光体含有シリコーン樹脂組成物の光学特性用試験片（波長変換部材）を得た。得られた厚み１ｍｍ、２０ｍｍφの試験片に対して、ＬＥＤチップ（ピーク波長４５０ｎｍ）から発光させた青色光を照射することで白色光を得ることができる発光装置を作製した。その装置から発光スペクトルをＳｐｈｅｒｅＯｐｔｉｃｓ社製２０ｉｎｃｈ積分球およびＯｃｅａｎＯｐｔｉｃｓ社製分光器ＵＳＢ２０００を用いて観測し、色度、光束（ルーメン）、Ｒａを計測した。測定結果を表５に示す。

The obtained silicone resin composition was cast into a 20 mmφ glass vial so as to have a thickness of 1 mm, and cured by heating at 150 ° C. for 5 minutes and then at 200 ° C. for 20 minutes. A characteristic test piece (wavelength conversion member) was obtained. A light-emitting device capable of obtaining white light was produced by irradiating the obtained test piece having a thickness of 1 mm and 20 mmφ with blue light emitted from an LED chip (peak wavelength: 450 nm). The emission spectrum was observed from the apparatus using a 20 inch integrating sphere manufactured by Sphere Optics and a spectroscope USB2000 manufactured by Ocean Optics, and chromaticity, luminous flux (lumen), and Ra were measured. Table 5 shows the measurement results.

Next, for the light emitting devices manufactured in Examples 1 to 4 and Comparative Example 2, the excitation spectrum at 540 nm emission was measured using a spectrofluorometer F-4500 manufactured by Hitachi, and the excitation intensity at 450 nm was 1.0. The relative excitation intensity at 430 nm to 470 nm was calculated.
As shown in Table 6, in the phosphors shown in Examples 1 to 4, the difference between the maximum value and the minimum value of the relative excitation spectrum intensity in the wavelength range of 430 to 470 nm is 0.25 or less, The difference between the maximum value and the minimum value of the relative excitation spectrum intensity in the wavelength range of 440 to 460 nm is 0.13 or less, and a stable emission spectrum is obtained at 430 to 470 nm excitation, and particularly stable emission spectrum at 440 to 460 nm. Is obtained.

Next, regarding the light emitting devices manufactured in Examples 1 to 4 and Comparative Example 2, the change in chromaticity Δu′v ′ when the excitation light source is changed to a xenon spectral light source and the excitation wavelength is changed from 445 nm to 455 nm. Was measured. Spectral light source manufactured by Spectra Corp. 20
inch integrating sphere (LMS-200) and spectroscope manufactured by Carl Zeiss (Solid L)
ambda UV-Vis), the change in chromaticity was observed. Excitation wavelength is 445 nm, 4
Measure the chromaticity and lumen value in the case of 48 nm, 450 nm, 452 nm, 454 nm, and 455 nm, respectively. In chromaticity, calculate the average value (u ′ _ave , v ′ _ave ), and then calculate the distance from the average value. The relative luminance was calculated with respect to the lumen value when the lumen having an excitation wavelength of 455 nm was set to 1. They are shown in FIG. 2 and Table 7, respectively.

  As can be seen from Table 5, FIG. 2 and Table 6, it can be seen that the light emitting device using the phosphor of the present invention has high luminance and good binning characteristics.

(Each wavelength excitation intensity when 450 nm excitation intensity is 1.0 in the mixed powder)
The phosphors were weighed in a sealed container at the blending ratio shown in Table 8, and mixed phosphors were obtained by thoroughly stirring and mixing.
Relative excitation intensity at 430 nm to 465 nm when the excitation spectrum at 575 nm of light emission was measured using a spectrofluorimeter F-4500 manufactured by Hitachi, Ltd., and the excitation intensity at 450 nm was 1.0. Was calculated.
As shown in Table 9, in the phosphors shown in Examples 5 to 8, the difference between the maximum value and the minimum value of the relative excitation spectrum intensity in the wavelength range of 430 to 465 nm is 0.12 or less, The difference between the maximum value and the minimum value of the relative excitation spectrum intensity in the wavelength range of 440 to 460 nm is 0.05 or less, and a stable emission spectrum is obtained in the excitation of 430 to 465 nm, and in particular, the emission spectrum is stable in the range of 440 to 460 nm. Is obtained.

DESCRIPTION OF SYMBOLS 10 Light emitting device 1 Blue semiconductor light emitting element 2 Wiring board 2a Chip mounting surface 3 Wavelength conversion member

Claims (27)

A light emitting device including a blue semiconductor light emitting element and a wavelength conversion member,
The wavelength conversion member is represented by the following general formula (X), and includes a yellow-green phosphor whose emission wavelength spectrum has a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm,
The light-emitting device whose excitation spectrum intensity change rate in the light emission wavelength of 540 nm of this wavelength conversion member is 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed. The light emitting device according to claim 1, wherein an excitation spectrum intensity change rate of the yellow-green phosphor is 0.13 or less.
However, the excitation spectrum intensity change rate of the yellow-green phosphor is the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the yellow-green phosphor at 450 nm is 1.0. Expressed as a difference. The chromaticity change Δu′v ′ of light emitted from the light emitting device when the emission wavelength of the blue semiconductor light emitting element is continuously changed from 445 nm to 455 nm satisfies Δu′v ′ ≦ 0.005. Item 3. The light emitting device according to Item 1 or 2.
However, Δu′v ′ is the distance between the chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength inm from 445 nm to 455 nm and the average value (u ′ _ave , v ′ _ave ) of chromaticity from 445 nm to 455 nm. . The light emitting device according to any one of claims 1 to 3, wherein the yellow-green phosphor is represented by the following general formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is selected from the group of Y and Lu, and 1 or 2 or more elements including 90% or more of Y. E is Ga, or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2)   The light-emitting device according to any one of claims 1 to 4, wherein an intensity change of an excitation spectrum of the yellow-green phosphor is 4.0% or less of an excitation light spectrum intensity at 450 nm from 440 nm to 460 nm.   The light emitting device according to any one of claims 1 to 5, further comprising a red phosphor.   The light emitting device according to claim 6, wherein the intensity change of the excitation spectrum of the red phosphor is 4.0% or less of the excitation light spectrum intensity at 450 nm from 440 nm to 460 nm.   The red phosphor includes a red phosphor having an emission peak wavelength of 620 to 640 nm and a half width of 2 nm to 100 nm in a composition weight ratio of 50% or more with respect to the total amount of the red phosphor. The light-emitting device of description.   The light emitting device according to any one of claims 6 to 8, wherein the red phosphor is SCASN.   The light emitting device according to any one of claims 6 to 9, further comprising a red phosphor having an emission peak wavelength of 640 to 670 nm and a half-value width of 2 nm to 120 nm as the red phosphor.   The light emitted from the light emitting device has a deviation duv from a light-colored black body radiation locus of -0.0200 to 0.0200, and a color temperature of 1800K to 7000K. The light emitting device according to 1.   The light emitting device according to any one of claims 1 to 10, wherein a color temperature of light emitted from the light emitting device is 7000K or more and 20000K or less. A blue semiconductor light emitting device;
A light-emitting device including a wavelength conversion member containing a yellow-green phosphor,
The yellow-green phosphor is represented by the following general formula (2), and the difference between the maximum value and the minimum value of the excitation intensity normalized by the excitation spectrum intensity of 450 nm when excited at the excitation wavelength of 440 nm to 460 nm is 0.05. The following phosphors:
(Y, Ce) ₃ (Ga, Al) _f O _g (2)
(4.5 ≦ f ≦ 5.5, 10.8 ≦ g ≦ 13.2)
A light emitting device having a chromaticity change Δu′v ′ from an average chromaticity of light emitted from a wavelength conversion member when excited at an excitation wavelength of 445 nm to 455 nm is 0.005 or less.   The light-emitting device according to claim 1, wherein the blue semiconductor light-emitting element and a wavelength conversion member including the yellow-green phosphor are disposed via a space. A yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm;
A wavelength conversion member including a transparent material,
A wavelength conversion member having an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member of 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed. The excitation spectrum intensity change rate of the yellow-green phosphor is 0.13 or less.
The wavelength conversion member according to claim 15.
However, the excitation spectrum intensity change rate of the yellow green phosphor is the maximum value and minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the yellow green phosphor at 450 nm is 1.0. It is expressed by the difference. The chromaticity change Δu′v ′ of light emitted from the wavelength conversion member when the excitation wavelength is continuously changed from 445 nm to 455 nm satisfies Δu′v ′ ≦ 0.005. The wavelength conversion member as described.
However, Δu′v ′ is the distance between the chromaticity (u ′ _i , v ′ _i ) at an arbitrary wavelength inm from 445 nm to 455 nm and the average value (u ′ _ave , v ′ _ave ) of chromaticity from 445 nm to 455 nm. . The wavelength conversion member according to any one of claims 15 to 17, wherein the yellow-green phosphor is represented by the following general formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is selected from the group of Y and Lu, and 1 or 2 or more elements including 90% or more of Y. E is Ga, or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2) A yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm to 550 nm when excited at 450 nm;
A phosphor composition comprising a transparent material,
A phosphor composition, wherein when the phosphor composition is molded into a wavelength conversion member, an excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member is 0.25 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 470 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed. The phosphor composition according to claim 19, wherein the yellow-green phosphor is represented by the following general formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is selected from the group of Y and Lu, and 1 or 2 or more elements including 90% or more of Y. E is Ga, or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2)   21. The phosphor composition according to claim 19 or 20, further comprising a red phosphor. A phosphor mixture containing a yellow-green phosphor represented by the following general formula (X) and having an emission wavelength spectrum having a peak wavelength of 530 nm or more and 550 nm or less when excited at 450 nm,
The phosphor mixture, wherein an excitation spectrum intensity change rate at an emission wavelength of 575 nm of the phosphor mixture is 0.12 or less.
(Y, Ce, Tb, Lu) _x (Ga, Sc, Al) _y O _z (X)
(X = 3, 4.5 ≦ y ≦ 5.5, 10.8 ≦ z ≦ 13.4)
However, the excitation spectrum intensity change rate of the phosphor mixture is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 430 nm to 465 nm when the excitation spectrum intensity of the phosphor mixture at 450 nm is 1.0. It is represented by   The phosphor mixture according to claim 22, further comprising a red phosphor. When the phosphor mixture and silicone resin are mixed, or polycarbonate resin is kneaded and molded into a wavelength conversion member, the excitation spectrum intensity change rate at an emission wavelength of 540 nm of the wavelength conversion member is 0.05 or less. The phosphor mixture according to claim 22 or 23.
However, the excitation spectrum intensity change rate of the wavelength conversion member is the difference between the maximum value and the minimum value of the excitation spectrum intensity in the range of 440 nm to 460 nm when the excitation spectrum intensity of the wavelength conversion member at 450 nm is 1.0. expressed. The phosphor mixture according to any one of claims 22 to 24, wherein the yellow-green phosphor is represented by the following general formula (1).
M _a A _b E _c Al _d O _e (1)
(M is a Ce element. A is selected from the group of Y and Lu, and 1 or 2 or more elements including 90% or more of Y. E is Ga, or Ga and Sc. A + b = 3, 4.5 ≦ c + d ≦ 5.5, 10.8 ≦ e ≦ 13.2, 0 ≦ a ≦ 0.9, 0.8 ≦ c ≦ 1.2)   The general illuminating device containing the light-emitting device of any one of Claim 1 to 11, 13, and 14.   The backlight containing the light-emitting device of any one of Claim 1 to 10 and 12 to 14.

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