JP2019210367A - Phosphor and phosphor composition using the same, and light-emitting device, illumination device and image display device using the same - Google Patents

Abstract

To provide a new phosphor that emits green or yellow light by near-ultraviolet or short-wavelength visible light, and a phosphor composition and the like using the phosphor.SOLUTION: The phosphor contains a crystal phase having at least M element, A element, Li and C element (where M element represents an activation element, A element represents at least one element selected from the group of Ca, Sr and Ba, and C element represents Al and/or Ga), and further having N and/or O. In the crystal phase, lattice constants satisfy 7.10≤(lattice constant a)≤8.68, 7.10≤(lattice constant b)≤8.68 and 2.86×n≤(lattice constant c)≤3.49×n, where n represents one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27 and 28, and the ranges of the lattice constant c designated by n may overlap.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a novel phosphor, a phosphor composition using the same, and a light emitting device, an illumination device, an image display device, and the like using the same.

  2. Description of the Related Art In recent years, demands for illumination using an LED, a backlight, and the like are increasing in devices using light emitting devices such as image display devices and illumination devices in response to energy saving. As LEDs used in these, white light-emitting LEDs that emit white light by using together LED chips that emit light in the near ultraviolet or short wavelength visible region and phosphors are becoming common. As such white light emitting LED, those using a phosphor that emits yellow light using blue light emitted from a blue LED chip as excitation light are mainly used. In recent years, attempts have been made to use phosphors that emit blue light, phosphors that emit green light, and phosphors that emit red light. In this type of light emitting device, excellent light emission characteristics are required, and phosphors having higher light emission characteristics are eagerly desired.

As a green phosphor, for example, Patent Document 1 discloses a sialon phosphor containing an alkaline earth element. As the yellow to orange phosphor, for example, Patent Document 2 discloses an α sialon phosphor represented by a composition formula of Sr _1.11 Al _2.25 Si _9.75 N ₁₆ : Eu _0.02 . .

Further, for the purpose of improving the light emission characteristics, a phosphor containing Li has been studied. As a green phosphor containing Li, for example, Patent Document 3 discloses a stress-stimulated luminescent material of strontium aluminate containing Li. For example, Patent Document 4 discloses a Li ₁ Ba ₂ Al ₁ Si ₇ N ₁₂ : Eu ²⁺ phosphor. As a red phosphor containing Li, for example, Patent Document 5 discloses a solid solution of CaAlSiN ₃ : Eu ²⁺ and LiSi ₂ N ₃ . Furthermore, for example, Patent Document 6 discloses an SLA phosphor represented by a composition of SrLiAl ₃ N ₄ : Eu ²⁺ .

WO2011 / 016486A1 JP 2009-256558 A Japanese Patent Laying-Open No. 2015-67799 WO2014 / 003076A1 WO2006 / 126567A1 WO2013 / 175336A1

  As described above, phosphors of various colors have been developed, but phosphors with further improved light emission characteristics are desired.

  The present invention has been made in view of the above problems. That is, an object of the present invention is to provide a novel phosphor that emits green to yellow light by light in the near ultraviolet or short wavelength visible region, a phosphor composition using the same, and the like. Another object of the present invention is to provide a light emitting device, a lighting device, an image display device, and the like using the above phosphor.

  As a result of intensive investigations on new phosphors to solve the above-mentioned problems, the present inventors have a crystal structure different from that of conventional phosphors, and are green to yellow by light in the near ultraviolet or short wavelength visible region. The inventors have found a novel phosphor that emits light and completed the present invention.

That is, the present invention provides various specific embodiments shown below.
<1> M element, A element, Li, and C element (where M element is an active element, A element is at least one element selected from the group consisting of Ca, Sr, and Ba, and C element is Al) And / or Ga), and further includes a crystal phase having N and / or O, and the crystal phase has a lattice constant satisfying the following range.
7.10 ≦ lattice constant a ≦ 8.68
7.10 ≦ lattice constant b ≦ 8.68
2.86 × n ≦ lattice constant c ≦ 3.49 × n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28. (Note that the ranges of the lattice constant c specified by n may overlap.)

<2> The phosphor according to <1>, wherein at least Li and C elements are present at the same crystal site, and the crystal system is a tetragonal system.
<3> The element according to <1> or <2>, further including Mg and / or E element (wherein E element is at least one element selected from the group consisting of Si and Ge) Phosphor.

<4> The phosphor according to <3>, wherein the crystal phase includes a crystal phase represented by the following formula [1].
M _a A _1-a Li _b-d1 C _c-d2-e Mg _{d1 + d2} E _e N _f O _g [1]
(In the above formula [1], a, b, c, d1, d2, e, f, and g are values that satisfy the following formula independently.
0 <a ≦ 0.2
1.0 ≦ b ≦ 3.5
1.0 ≦ c ≦ 4.0
0 ≦ d1 ≦ 3.5
0 ≦ d2 ≦ 4.0
0 ≦ e ≦ 4.0
0 ≦ f ≦ 5.0
0 ≦ g ≦ 5.0
4.0 ≦ b + c ≦ 5.0
4.0 ≦ f + g ≦ 5.0
0 ≦ b−d1
0 ≦ c-d2-e)

<5> In the above formula [1], 0 ≦ d1 ≦ 0.6, 0 ≦ d2 ≦ 0.6, and 0 ≦ e ≦ 1.0. Phosphor.
<6> In the above formula [1], 4.5 ≦ b + c ≦ 5.0, 0 ≦ d1 + d2 ≦ 1.0, and 4.5 ≦ f + g ≦ 5.0 <4 > Or <5>.

<7> The phosphor according to any one of <1> to <6>, including a crystal phase represented by the following formula [2].
_{M a 'A m / n-} a' Li x-y1 C 4-x-y2-z Mg y1 + y2 E z N 4 + 2m / n-2x + y1-y2 + z O 2x-y1 + y2-z-2m / n [2]
(In said formula [2], a ', m, n, x, y1, y2, and z are values which satisfy | fill the following formula each independently.
0 <a ′ ≦ 0.2 × m / n
4/5 ≦ m / n ≦ 8/9
m / n ≦ x ≦ 2 + m / n
0 ≦ y1 ≦ 0.6
0 ≦ y2 ≦ 0.6
0 ≦ y1 + y2 ≦ 1.0
0 ≦ z ≦ 1.0
0 ≦ xy
0 ≦ 4-x−y2−z)

<8> Any one of <1> to <7>, wherein the M element includes at least one element selected from the group consisting of Eu, Ce, Pr, Sm, Tb, Dy, and Yb. The phosphor according to Item.
<9> n is any one integer selected from 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, and 28. The phosphor according to any one of <8>.
<10> In the above formula [2], 22/27 ≦ m / n ≦ 7/8, and 0.5 × m / n + 0.5 × (2 + m / n) ≦ x ≦ 2 + m / n The phosphor according to any one of <7> to <9>.
<11> In the above formula [2], 0 ≦ y1 + y2 ≦ 0.1, and 0 ≦ z ≦ 0.1, The fluorescence according to any one of <7> to <10> body.

<12> The phosphor according to any one of <1> to <11>, wherein the M element includes Eu, the A element includes Sr, and the C element includes Al.
<13> The phosphor according to any one of <3> to <12>, wherein the element E contains Si.
<14> n is any one integer selected from 6, 7, 13, 17, and 23, The phosphor according to any one of <1> to <13>,
<15> In the above formula [2], 14/17 ≦ m / n ≦ 6/7, and 0.25 × m / n + 0.75 × (2 + m / n) ≦ x ≦ 2 + m / n The phosphor according to any one of <7> to <14>.
<16> The element according to any one of <3> to <15>, wherein the M element is Eu, the A element is Sr, the C element is Al, and the E element is Si. Phosphor.

<17> In the above formula [2], n is 6, and 0.05 × m / n + 0.95 × (2 + m / n) ≦ x ≦ 2 + m / n <7> to <16 > The phosphor according to any one of the above.
<18> The phosphor according to <17>, wherein m is 5 and n is 6 in the above formula [2].

<19> In the above formula [2], n is 7, and <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≦ x ≦ 2 + m / n > The phosphor according to any one of the above.
<20> The phosphor according to <19>, wherein in the formula [2], m is 6 and n is 7.

<21> In the above formula [2], n is 13, <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≦ x ≦ 2 + m / n > The phosphor according to any one of the above.
<22> The phosphor according to <21>, wherein in the above formula [2], m is 11 and n is 13.

<23> In the above formula [2], n is 17, <7> to <16, wherein 0.05 × m / n + 0.95 × (2 + m / n) ≦ x ≦ 2 + m / n > The phosphor according to any one of the above.
<24> The phosphor according to <23>, wherein in the formula [2], m is 14 and n is 17.

<25> In the above formula [2], n is 23, and 0.05 × m / n + 0.95 × (2 + m / n) ≦ x ≦ 2 + m / n <7> to <16 > The phosphor according to any one of the above.
<26> The phosphor according to <25>, wherein in the above formula [2], m is 19 and n is 23.

<27> F and / or Cl is further contained, The content rate of the elemental conversion of F and Cl is 5000 ppm or less in total, As described in any one of <1>-<26> characterized by the above-mentioned. Phosphor.
<28> A phosphor composition comprising the phosphor according to any one of <1> to <27>, wherein the phosphor is contained in an amount of 20% by mass or more based on the total amount.

<29> An excitation light source that emits light in the near ultraviolet or short wavelength visible region, and a phosphor that converts at least a part of the light emitted by the excitation light source into a different emission spectrum, wherein the phosphor comprises: A light emitting device comprising at least the phosphor according to any one of 1 to 27 and / or the phosphor composition according to claim 28.
<30> An illumination device comprising the light emitting device according to <29>.
<31> An image display device comprising the light emitting device according to <29>.

  According to the present invention, a novel phosphor having a crystal structure different from that of conventional phosphors and emitting green to yellow light by light in the near ultraviolet or short wavelength visible region, and a phosphor composition using the same realizable. This novel phosphor is particularly useful in white light emitting LED applications due to its emission characteristics (excitation spectrum, emission spectrum, emission color, emission efficiency). And the light-emitting device containing the novel fluorescent substance of this invention, and the illuminating device and image display apparatus containing this light-emitting device are highly efficient and high quality.

It is a figure which shows Farey tree of the fluorescent substance of this invention. 5 is a graph showing an excitation spectrum and an emission spectrum of the phosphor of Reference Example 1. 3 is a graph showing an emission spectrum of the phosphor of Example 1. It is a graph which shows the excitation spectrum and emission spectrum of the fluorescent substance of Example 2. 6 is a graph showing an emission spectrum of Example 3. It is a graph which shows the excitation spectrum and emission spectrum of the fluorescent substance of Example 4. 6 is a graph showing an emission spectrum of Example 5. It is a graph which shows the relationship between n value and the lattice constant a in Examples 1-5 and Reference Example 1. It is a graph which shows the relationship between n value and the lattice constant c in Examples 1-5 and Reference Example 1.

  Hereinafter, embodiments of the present invention will be described in detail. The following embodiments are examples (representative examples) of the embodiments of the present invention, and the present invention is not limited to these. In addition, the present invention can be implemented with any modifications without departing from the scope of the invention. In addition, the numerical range represented using “to” in this specification means a range including numerical values described before and after “to” as the lower limit value and the upper limit value. For example, the numerical range of “1 to 100” includes both the lower limit value “1” and the upper limit value “100”. The same applies to other numerical ranges.

In the phosphor composition formulas in this specification, each composition formula is delimited by a punctuation mark (,). When a plurality of elements are listed by separating them with a comma (,), one or two or more of the listed elements may be contained in any combination and ratio. For example, the composition formula “(Ca, Sr, Ba) Al ₂ O ₄ : Eu” has “CaAl ₂ O ₄ : Eu”, “SrAl ₂ O ₄ : Eu”, and “BaAl ₂ O ₄ : Eu”. If: the _{"Ca 1-x Sr x Al 2} O 4 Eu ": a _{"Sr 1-x Ba x Al 2} O 4 Eu ": the _{"Ca 1-x Ba x Al 2} O 4 Eu " _{"Ca 1-x-y Sr x} Ba y Al 2 O 4: Eu " (. However, in these formulas, is 0 <x <1,0 <y < 1,0 <x + y <1) and a comprehensive It is assumed that

<Phosphor>
The phosphor of the present embodiment includes an M element, an A element, Li, and a C element (where the M element is an active element, the A element is at least one element selected from the group consisting of Ca, Sr, and Ba, C element is Al and / or Ga) and further includes a crystal phase having N and / or O, and the lattice constant of the crystal phase satisfies the following range.
7.10 ≦ lattice constant a ≦ 8.68
7.10 ≦ lattice constant b ≦ 8.68
2.86 × n ≦ lattice constant c ≦ 3.49 × n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28. (Note that the ranges of the lattice constant c specified by the n value may overlap.)

Here, in the phosphor, the number of A elements in the c-axis direction in the unit cell is m, the number of C elements (N, O) ₄ in the c-axis direction is n, the composition ratio of M elements is a, and the composition of Li When the ratio is x, it can also be said that it is represented by the general formula M _{a Am /} na Li _x C _4−x N _{4 + 2 m / n−2x} O _{2x−2 m / n} .

The phosphor represented by the general formula includes all substance groups existing at a certain m / n value. m / n = 1/1, 8/9, 7/8, 13/15, 6/7, 17/20, 11/13, 16/19, 5/6, 19/23, 14/17, 23 / Substances corresponding to 28, 9/11, 22/27, 13/16, 17/21, 4/5 are 1/1 crystal, 8/9 crystal, 7/8 crystal, 13/15 crystal, 6/7 crystal , 17/20 crystal, 11/13 crystal, 16/19 crystal, 5/6 crystal, 19/23 crystal, 14/17 crystal, 23/28 crystal, 9/11 crystal, 22/27 crystal, 13/16 crystal , 17/21 crystal, and 4/5 crystal, respectively.
Moreover, the relationship between substances existing at a certain m / n value and these substances can also be explained by the Farey tree. FIG. 1 shows a Farey tree of the phosphor according to the present embodiment. Hereinafter, the substance group of the present invention may be referred to as an FT substance group.
This FT material group shows different crystal structures depending on the ratio (: m / n) of the number of stacked M elements in the c-axis direction and the number of stacked C elements (N, O) _{4 in the} c-axis direction. Further, the ratio of N and O is determined corresponding to the composition ratio (x) of Li and C elements. In the FT substance group, the initial structure of another m / n crystal can be derived from the crystal structure of a certain m / n crystal. This FT substance group is a substance group having a crystal structure in which n C elements (N, O) ₄ are stacked in the c-axis direction. Therefore, the c-axis lattice constant of each substance can be roughly arranged as n times the c-axis lattice constant of the 1/1 crystal. Hereinafter, each element will be described in detail.

  M element is an activation element, and includes europium (Eu), manganese (Mn), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), terbium (Tb), dysprosium (Dy), It represents one or more elements selected from the group consisting of holmium (Ho), erbium (Er), thulium (Tm) and ytterbium (Yb). The M element preferably contains at least Eu, and more preferably Eu.

  Further, all or part of Eu may be substituted with one or more elements selected from the group consisting of Ce, Pr, Sm, Tb, Dy and Yb. That is, the M element preferably includes Eu and at least one element selected from the group consisting of Ce, Pr, Sm, Tb, Dy, and Yb. From the viewpoint of light emission quantum efficiency, Eu and Ce are more preferable. That is, the M element is more preferably Eu and / or Ce, and more preferably Eu. In addition, although the content rate of Eu with respect to the whole M element is not specifically limited, 50 mol% or more is preferable, 70 mol% or more is more preferable, 90 mol% or more is especially preferable.

  The A element represents at least one element selected from the group consisting of calcium (Ca), strontium (Sr), and barium (Ba). The element A preferably contains Sr, more preferably Sr. The A element may be partially substituted with a divalent metal element other than the alkaline earth metal element, such as zinc (Zn).

  Li represents lithium. Li may be partially substituted with other monovalent elements such as sodium (Na), potassium (K), rubidium (Rb), cesium (Cs) and the like.

  The C element represents aluminum (Al) and / or gallium (Ga). The C element preferably contains Al, more preferably Al. The C element is another trivalent element such as boron (B), indium (In), scandium (Sc), yttrium (Y), lanthanum (La), gadolinium (Gd), lutetium (Lu), and the like. May be partially substituted with.

  In addition, the phosphor of the present embodiment is not limited to the above-mentioned minimum constituent elements, but other elements such as halogen atoms such as fluorine atom (F), chlorine atom (Cl), bromine atom (Br), iodine atom (I), etc. May be included. Halogen atoms can be introduced not only as impurities in the raw metal but also during the manufacturing process such as the pulverization process or nitriding process. In particular, when halides are used as the flux, halogen atoms are present in the phosphor. It tends to be included with high probability.

  The lattice constant a of the phosphor of the present embodiment is usually 7.10 mm or more, preferably 7.49 mm or more, more preferably 7.65 mm or more, and usually 8.68 mm or less, preferably 8.28 mm or less, more Preferably it is 8.12 mm or less.

  Further, the lattice constant b is usually 7.10 mm or more, preferably 7.49 mm or more, more preferably 7.65 mm or more, and usually 8.68 mm or less, preferably 8.28 mm or less, more preferably 8.12 mm. It is as follows.

  Further, the lattice constant c is usually 2.86 × nÅ or more, preferably 3.02 × nÅ or more, more preferably 3.08 × nÅ or more, and usually 3.49 × nÅ or less, preferably 3.33. × nÅ or less, more preferably 3.27 × nÅ or less.

  N is usually 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, 28, preferably 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, 28, more preferably 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, 28 More preferably 6, 7, 13, 15, 17, 19, 20, 23, 28, still more preferably 6, 7, 13, 17, 19, 20, 23, particularly preferably 6, 7, 13 , 17, 23.

  The phosphor of this embodiment has a tetragonal crystal structure in the crystal structure. In the crystal structure, at least Li and C elements are present at the same crystal site.

  The phosphor of this embodiment may further contain Mg and / or E element (wherein E element is at least one element selected from the group consisting of Si and Ge).

  Mg represents magnesium. Mg may be partially substituted with a divalent metal element other than the alkaline earth metal element, such as zinc (Zn).

  The element E represents at least one element selected from the group consisting of silicon (Si) and germanium (Ge). The element E preferably contains Si, more preferably Si. The E element may be partially substituted with other tetravalent elements such as tin (Sn), titanium (Ti), zirconium (Zr), hafnium (Hf), and the like.

The phosphor of this embodiment preferably includes a crystal phase having a composition represented by the following formula [1].
M _a A _1-a Li _b-d1 C _c-d2-e Mg _{d1 + d2} E _e N _f O _g [1]
(In the above formula [1], a, b, c, d1, d2, e, f, and g are values that satisfy the following formula independently.
0 <a ≦ 0.2
1.0 ≦ b ≦ 3.5
1.0 ≦ c ≦ 4.0
0 ≦ d1 ≦ 3.5
0 ≦ d2 ≦ 4.0
0 ≦ e ≦ 4.0
0 ≦ f ≦ 5.0
0 ≦ g ≦ 5.0
4.0 ≦ b + c ≦ 5.0
4.0 ≦ f + g ≦ 5.0
0 ≦ b−d1
0 ≦ c-d2-e)

  a represents the content of M element, and the range thereof is usually 0 <a ≦ 0.2, the lower limit is preferably 0.001, more preferably 0.02, and the upper limit is Preferably it is 0.15, More preferably, it is 0.1.

  b represents the Li content, and the range is usually 1.0 ≦ b ≦ 3.5, and the lower limit is preferably 1.56, more preferably 2.14, and even more preferably 2.73. Particularly preferred is 2.75, and most preferred is 3.22. Moreover, the upper limit is preferably 3.47, more preferably 3.45, still more preferably 3.44, and particularly preferably 3.43.

  c represents the content of C element, and the range thereof is usually 1.0 ≦ c ≦ 4.0, and the lower limit is preferably 1.25, more preferably 1.29, and still more preferably 1. 31 and particularly preferably 1.33, and the upper limit thereof is preferably 3.32, more preferably 2.68, still more preferably 2.04, and particularly preferably 1.55.

  d1 represents the substitution amount of Mg with respect to Li, and the range is usually 0 ≦ d1 ≦ 3.5, and the upper limit is preferably 1.5, more preferably 0.6, and still more preferably 0.8. 5, particularly preferably 0.1.

  d2 represents the substitution amount of Mg with respect to Al, and the range is usually 0 ≦ d2 ≦ 4.0, and the upper limit is preferably 2.0, more preferably 0.6, and still more preferably 0.8. 5, particularly preferably 0.1.

  e represents the substitution amount of the E element with respect to Al, and the range is usually 0 ≦ e ≦ 4.0, and the upper limit is preferably 2.0, more preferably 0.6, and even more preferably 0. .5, particularly preferably 0.1.

  f represents the content of N, and the range thereof is usually 0 ≦ f ≦ 5.0, and the upper limit thereof is preferably 4.50, more preferably 3.71, and even more preferably 2.45. The ratio is preferably 1.22, particularly preferably 1.21, and most preferably 0.24.

  g represents the content of O, the range is usually 0 ≦ g ≦ 5.0, and the lower limit is preferably 1.13, more preferably 2.29, even more preferably 3.46, Preferably it is 3.50, most preferably 4.43.

The range of b + c is usually 4.0 ≦ b + c ≦ 5.0, preferably 4.5 ≦ b + c ≦ 5.0, and the lower limit value is more preferably 4.57, still more preferably 4.62. The upper limit is preferably 4.67, and more preferably 4.91, even more preferably 4.87, and particularly preferably 4.86.

The range of f + g is usually 4.0 ≦ f + g ≦ 5.0, preferably 4.5 ≦ f + g ≦ 5.0, and the lower limit is more preferably 4.57, still more preferably 4.62. The upper limit is preferably 4.67, and more preferably 4.91, even more preferably 4.87, and particularly preferably 4.86.

  In the above formula [1], 0 ≦ d1 ≦ 0.6, 0 ≦ d2 ≦ 0.6, and preferably 0 ≦ e ≦ 1.0.

In the above formula [1], it is preferable that the following formula is further satisfied.
4.5 ≦ b + c ≦ 5.0
0 ≦ d1 + d2 ≦ 1.0
4.5 ≦ f + g ≦ 5.0

  The range of d1 + d2 is preferably 0 ≦ d1 + d2 ≦ 1.0, and the upper limit is more preferably 0.6, still more preferably 0.5, and particularly preferably 0.1.

The phosphor according to this embodiment preferably includes a crystal phase having a composition represented by the following formula [2].
_{M a 'A m / n-} a' Li x-y1 C 4-x-y2-z Mg y1 + y2 E z N 4 + 2m / n-2x + y1-y2 + z O 2x-y1 + y2-z-2m / n [2]

  In said formula [2], M element, A element, Li, C element, Mg, E element, N, and O are synonymous with what was demonstrated by said formula [1].

In the above formula [2], a ′, m, n, x, y1, y2, and z are values independently satisfying the following formula.
0 <a ′ ≦ 0.2 × m / n
4/5 ≦ m / n ≦ 8/9
m / n ≦ x ≦ 2 + m / n
0 ≦ y1 ≦ 0.6
0 ≦ y2 ≦ 0.6
0 ≦ y1 + y2 ≦ 1.0
0 ≦ z ≦ 1.0
0 ≦ xy
0 ≦ 4-xy-2z

  a ′ represents the content of M element, and its range is usually 0 <a ′ ≦ 0.2 × m / n, and the lower limit is preferably 0.001 × m / n, more preferably 0. 0.02 × m / n, and the upper limit is preferably 0.15 × m / n, more preferably 0.1 × m / n.

  m / n represents the content of A, and its range is usually 4/5 ≦ m / n ≦ 8/9, and the lower limit is preferably 17/21, more preferably 22/27, even more preferably. Is 23/28, particularly preferably 14/17. The upper limit is preferably 7/8, more preferably 13/15, and even more preferably 6/7.

  x represents the content of Li, the range is usually m / n ≦ x ≦ 2 + m / n, and the lower limit is m / n, preferably 0.75 × m / n + 0.25 × (2 + m / N), more preferably 0.5 × m / n + 0.5 × (2 + m / n), even more preferably 0.25 × m / n + 0.75 × (2 + m / n), particularly preferably 0.05 × m /N+0.95×(2+m/n), and the upper limit is 2 + m / n, preferably 0.25 × m / n + 0.75 × (2 + m / n), more preferably 0.5 ×. m / n + 0.5 × (2 + m / n), more preferably 0.75 × m / n + 0.25 × (2 + m / n), particularly preferably 0.95 × m / n + 0.05 × (2 + m / n) is there.

  y1 represents the substitution amount of Mg with respect to Li, the range is usually 0 ≦ y1 ≦ 0.6, and the upper limit is preferably 0.5, more preferably 0.1.

  y2 represents the substitution amount of Mg with respect to Al, the range is normally 0 ≦ y2 ≦ 0.6, and the upper limit is preferably 0.5, more preferably 0.1.

  z represents the amount of substitution of E with respect to Al, and the range is usually 0 ≦ z ≦ 1.0, and the upper limit is preferably 0.5, more preferably 0.1.

  In the above formula [2], 0 ≦ y1 + y2 ≦ 0.1 and preferably 0 ≦ z ≦ 0.1.

  Any content is within the above-described range, which is preferable in terms of good emission characteristics of the obtained phosphor, particularly emission luminance.

  Specific examples of the phosphor represented by the above formula [1] or [2] include those shown in Table 1 and Table 2, but are not particularly limited thereto.

<Physical properties of phosphors>
[Luminescent color]
The emission color of the phosphor of the present embodiment can be excited by light in the near ultraviolet region to the blue region having a wavelength of 300 nm to 500 nm by adjusting the chemical composition and the like, whereby green, yellowish green, yellow, red For example, a desired emission color can be emitted.

[Emission spectrum]
The phosphor of this embodiment preferably has the following characteristics when an emission spectrum is measured when excited with light having a wavelength of 400 nm. That is, the peak wavelength (emission maximum wavelength) in the above-described emission spectrum is usually 500 nm or more, preferably 510 nm or more, more preferably 520 nm or more. Moreover, the upper limit is 620 nm or less normally, Preferably it is 600 nm or less, More preferably, it is 580 nm or less. It is preferable for the emission spectrum to be in the above-mentioned range since the obtained phosphor exhibits a good green to yellow color.

[Half width of emission spectrum]
In the phosphor of this embodiment, the half-value width of the emission peak in the above-mentioned emission spectrum is usually 100 nm or less, preferably 90 nm or less, more preferably 85 nm or less, and the lower limit is usually 30 nm or more. Within the above range, when used in a light emitting device such as a liquid crystal display device, a decrease in color purity is suppressed, and the color reproduction range tends to be widened, which is preferable.

  In addition, although it does not specifically limit as a light source for excitation for exciting the fluorescent substance of this embodiment with the light of wavelength 400nm, For example, GaN-type LED can be used. As the excitation light source, for example, an ultraviolet (or purple) LED light emitting element or a blue LED light emitting element that emits light having a wavelength of 300 to 500 nm can be used. As the LED light emitting element, a nitride semiconductor such as GaN or InGaN can be used. This is known, and by adjusting the composition, it can be a light-emitting light source that emits light of a predetermined wavelength. In addition, the measurement of the emission spectrum of the phosphor of this embodiment and the calculation of the emission peak wavelength, peak relative intensity, peak half-value width, and the like can be performed, for example, using a 150 W xenon lamp as an excitation light source and multi-channel CCD detection as a spectrum measurement device. This can be carried out using a fluorescence measuring device (manufactured by JASCO Corporation) equipped with a device C7041 (manufactured by Hamamatsu Photonics). For example, an LED light-emitting device can be manufactured by a known method as described in JP-A-5-152609, JP-A-7-99345, JP-A-2927279, etc. using the phosphor of the present invention. it can.

[Excitation wavelength]
The phosphor of this embodiment is usually excited to a wavelength range of 300 nm or more, preferably 350 nm or more, more preferably 380 nm or more, and usually 500 nm or less, preferably 490 nm or less, more preferably 480 nm or less, and even more preferably 460 nm or less. It has a peak (absorption maximum wavelength). That is, the phosphor of the present embodiment can be normally excited by light in the near ultraviolet to blue region.

[Crystal system and space group]
The crystal system in the phosphor of this embodiment is a tetragonal system. In addition, the space group in the phosphor of the present embodiment is not particularly limited as long as the average structure indicates a repetition period of the above-described length (that is, a period in which the lattice constant c is within a predetermined range), but “International Tables for It is preferable to belong to No. 85 (P 4 / n) or No. 87 (I 4 / m) based on Crystallography (Third, Revised Edition), Volume A SPACE-GROUP SYMMETRY. Here, the lattice constant and the space group can be obtained according to an ordinary method. Specifically, the lattice constant can be obtained by analyzing the results of X-ray diffraction and neutron diffraction by Rietveld, and the space group includes electron diffraction, X-ray diffraction using a single crystal, and It can be determined by analysis of neutron diffraction.

In the FT substance group of the present invention, the lattice constant changes when the constituent component is substituted with another element or the activating element is dissolved, but the crystal structure, the site occupied by the atom, and the The atomic position given by the atomic coordinates does not change so much that the chemical bond between the skeletal atoms is broken.
In the present invention, the length of the chemical bond between the atoms satisfying at least claim 1 and calculated from the lattice constant and the atomic coordinates obtained by analyzing the result of X-ray diffraction or neutron diffraction is each FT substance. If the length of the chemical bond between atoms calculated from the lattice constant of the group and the atomic coordinates is within ± 10%, it is determined that the crystal structure is the same as that of the phosphor of the present invention.

<Method for producing phosphor>
The method for producing the phosphor of the present embodiment is not particularly limited. For example, a raw material for element M as an activator (hereinafter sometimes referred to as “M source” as appropriate), a raw material for element A (hereinafter referred to as “M source”). , Sometimes referred to as “A source”), Li source (hereinafter sometimes referred to as “Li source” as appropriate), and C element source (hereinafter referred to as “C source” where appropriate). As well as a raw material for element E (hereinafter sometimes referred to as “E source” as appropriate) and a raw material for Mg (hereinafter referred to as “Mg source” where appropriate). A method including at least a step of mixing phosphor raw materials (mixing step) such as) and a step of baking the obtained mixture (baking step) is preferably used. Hereinafter, for example, the raw material of the element Eu may be referred to as “Eu source”, and the raw material of the element Sm may be referred to as “Sm source”. The raw material for the element Al may be referred to as “Al source”, the raw material for the element Si may be referred to as “Si source”, and so on.

[Phosphor material]
Phosphor raw materials such as M source, A source, Li source, C source, E source, and Mg source are those silicides, oxides, carbonates, nitrides, oxynitrides, halides (chlorides, fluorides). ), Acid fluorides, hydroxides, oxalates, sulfates, nitrates, organometallic compounds, or precursor compounds thereof, and the like are not particularly limited. As a phosphor raw material, 1 type can be used independently and 2 or more types can be used by arbitrary combinations and a ratio. Among these, oxides, nitrides, halides, carbonates, and silicides are preferable, and oxides, nitrides, and halides are more preferable.

  If necessary, the phosphor of this embodiment may be synthesized in advance and mixed with the raw material mixture as a seed crystal (seed crystal). By using the seed crystal in this way, crystallization and low-temperature synthesis are promoted, and a phosphor having a higher crystallinity tends to be easily obtained. In addition, the compounding ratio of the seed crystal is not particularly limited, but a range of 0.1 to 30 parts by mass with respect to 100 parts by mass of the phosphor raw material is preferable.

(M source)
Among the M sources that are activators, specific examples of Eu sources include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (C ₂ O ₄ ) ₃ · 10H ₂ O, EuF ₃ , EuCl _2. , EuCl ₃ , Eu (NO ₃ ) ₃ .6H ₂ O, EuN, EuNH and the like, but are not particularly limited thereto. Among these, Eu ₂ O ₃ , EuF ₃ , EuN and the like are preferable, and EuN is particularly preferable. On the other hand, specific examples of raw materials of other activating elements such as Sm source, Tm source, Yb source, etc., are compounds in which Eu is replaced with Sm, Tm, Yb, etc. in the respective compounds listed as specific examples of Eu source Is mentioned.

(A source)
Among the A sources, specific examples of the Sr source include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (C ₂ O ₄ ) · H ₂ O, Sr (OCOCH ₃ ) ₂ · 0.5H ₂ O, SrF ₂ , SrCl ₂ , Sr ₂ N, Sr ₃ N ₂ , SrNH, and the like can be mentioned, but not limited thereto. Among these, SrO, SrCO ₃ , Sr ₂ N, and Sr ₃ N ₂ are preferable. From the viewpoint of reactivity, those having a small particle diameter and high purity from the viewpoint of luminous efficiency are preferable. On the other hand, specific examples of raw materials of other alkaline earth metal elements such as a Ca source and a Ba source include compounds in which Sr is replaced with Ca, Ba or the like in each of the compounds listed as specific examples of the Sr source. .

(Li source)
Specific examples of the Li source include Li ₂ O, LiOH, Li ₂ CO ₃ , LiNO ₃ , Li ₂ SO ₄ , LiF, LiCl, Li ₃ N, LiNH ₂ and hydrates of these compounds. However, it is not particularly limited to these. Among these, Li ₂ O, Li ₂ CO ₃ , and Li ₃ N are preferable. Moreover, from the point of luminous efficiency, a thing with high purity is preferable. On the other hand, in the case where Li is partially substituted with other monovalent elements, specific examples of the other monovalent element raw materials include Li in Na, And compounds substituted with K, Rb, Cs and the like. Note that Li may be used as the Li source.

(C source)
Among the C sources, specific examples of the Al source include AlN, Al ₂ O ₃ , Al (OH) ₃ , AlOOH, Al (NO ₃ ) ₃ , AlF ₃ , AlCl _{3, and the} like. Not. Among these, AlN and Al ₂ O ₃ are preferable. Further, those having a small particle size and high purity from the viewpoint of light emission efficiency are preferable from the viewpoint of reactivity. On the other hand, specific examples of the Ga source include compounds in which Al is replaced with Ga in the compounds listed as specific examples of the Al source. Further, in the case where Al or Ga is partially substituted with other trivalent elements, specific examples of other trivalent element raw materials include the following in each compound given as a specific example of the Al source: And compounds substituted with B, In, Sc, Y, La, Gd, Lu and the like. The Al source may be single Al.

(Mg source)
Specific examples of the Mg source include MgO, Mg (OH) ₂ , MgCO ₃ , Mg (NO ₃ ) ₂ , MgSO ₄ , Mg (C ₂ O ₄ ) · H ₂ O, Mg (OCOCH ₃ ) ₂ . Examples thereof include 5H ₂ O, MgF ₂ , MgCl ₂ and hydrates thereof, Sr ₂ N, Sr ₃ N ₂ , SrNH, and the like, but are not particularly limited thereto. Among these, MgO, MgCO ₃ , and Mg ₃ N ₂ are preferable. From the viewpoint of reactivity, those having a small particle diameter and high purity from the viewpoint of luminous efficiency are preferable.

(E source)
Among the E sources, specific examples of the Si source include SiO ₂ or Si ₃ N _4, but are not particularly limited thereto. It is also possible to use a compound as a SiO _2. Specific examples of such a compound include SiO ₂ , H ₄ SiO ₄ , Si (OCOCH ₃ ) _{4 and the} like. Further, Si ₃ N ₄ is preferably one having a small particle size and high purity from the viewpoint of light emission efficiency from the viewpoint of reactivity. Furthermore, the thing with few content rates of the carbon element which is an impurity is preferable. On the other hand, specific examples of the Ge source include compounds in which Si is replaced with Ge in each of the compounds listed as specific examples of the Si source. Further, in the case where Si or Ge is partially substituted by other tetravalent elements, specific examples of the other raw materials for the tetravalent elements include Si in each of the compounds listed as specific examples of the Si source. Examples thereof include compounds substituted with Sn, Ti, Zr, Hf and the like. The Si source may be single Si.

  In addition, the above-mentioned M source, A source, Li source, C source, Mg source, and E source may each be used alone, or two or more may be used in any combination and ratio. In general, the above phosphor raw materials are weighed so that a phosphor having a desired composition can be obtained, mixed thoroughly using a ball mill or the like, then filled in a crucible, and fired at a predetermined temperature and atmosphere. By pulverizing and washing the fired product, the phosphor of the present embodiment having a desired composition can be obtained.

[Mixing process]
The mixing method of the phosphor raw material may be performed by a known method such as a dry mixing method or a wet mixing method, and is not particularly limited. Examples of the dry mixing method include a mixing method using a ball mill or the like. In addition, as a wet mixing method, for example, a solvent such as water or a dispersion medium is added to the above-described phosphor raw material, and mixed using a ball mill, a mortar, a pestle, or the like to obtain a solution or slurry state. It is a method of drying by spray drying, heat drying or natural drying. Examples of the solvent or dispersion medium include water, organic solvents, and mixed solvents thereof, but are not particularly limited thereto. For example, ester solvents such as methyl acetate, ethyl acetate, propyl acetate, and butyl acetate; ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; alcohol solvents such as methyl alcohol, ethyl alcohol, isopropyl alcohol, and n-butanol; Examples thereof include hydrocarbon solvents such as hexane, cyclohexane, methylcyclohexane, and ethylcyclohexane; aromatic hydrocarbon solvents such as toluene and xylene; or a mixed solvent thereof. Among these, water, alcohol solvents, and hydride solvents are preferable. These can be used alone or in combination of two or more.

[Baking process]
The obtained mixture is filled in a heat-resistant container such as a crucible or a tray made of a material having low reactivity with each phosphor raw material. The material of the heat-resistant container used at the time of firing is not particularly limited as long as the effect of the present embodiment is not impaired, and examples thereof include a crucible such as boron nitride and a container made of molybdenum.

  The firing temperature during the firing step varies depending on the pressure, the external atmosphere, and the like, but is usually in the temperature range of 500 ° C. or more and 2000 ° C. or less. The maximum temperature reached in this firing step is usually 600 ° C. or higher, preferably 700 ° C. or higher, more preferably 800 ° C. or higher, and usually 2000 ° C. or lower, preferably 1800 ° C. or lower. If the calcination temperature is too high, some of the elements contained in the matrix are partially eliminated, many defects are generated in the crystal, and the resulting crystal tends to be colored. If it is too low, the progress of the solid-phase reaction tends to be slow. Therefore, it may be difficult to obtain a phosphor having the target phase as a main phase. Even if the target crystal phase is obtained only slightly, if the firing temperature is too low, the element that becomes the luminescent center, for example, the Eu element in the crystal is not diffused, and the quantum efficiency may be lowered. In addition, if the firing temperature is too high, the elements constituting the target phosphor crystal are likely to volatilize, lattice defects are likely to be formed, or the crystal phase is decomposed and another phase may be generated as an impurity. .

  The pressure during the firing step varies depending on the firing temperature, the external atmosphere, and the like, but is usually 0.1 MPa or more, and is usually 200 MPa or less, preferably 190 MPa or less.

  The firing atmosphere in the firing step is arbitrary as long as the phosphor of the present embodiment can be obtained, but an atmosphere containing an inert gas (such as nitrogen or argon) is preferable. Specifically, a nitrogen gas atmosphere, a hydrogen-containing nitrogen atmosphere, and the like are preferable, and a nitrogen gas atmosphere is more preferable.

  The firing time in the firing step varies depending on the temperature, pressure, external atmosphere, etc. during firing, but is usually 10 minutes or longer, preferably 30 minutes or longer, and usually 72 hours or shorter, preferably 24 hours or shorter. If the firing time is too short, grain formation and grain growth cannot be promoted, so it tends to be difficult to obtain a phosphor with good characteristics. If the firing time is too long, volatilization of the constituent elements is promoted. For this reason, defects are induced in the crystal structure due to atomic deficiency, and it tends to be difficult to obtain a phosphor with good characteristics.

[Post-processing process]
The obtained fired product is granular or massive. This is pulverized, pulverized and / or classified into a powder of a predetermined size. Here, processing may be performed so that the median diameter (D50) is about 30 μm or less.
Specific examples of the treatment include a method of subjecting the synthesized product to sieve classification with an opening of about 45 μm, and passing the powder that has passed through the sieve to the next step, or the synthesized product to a general method such as a ball mill, a vibration mill, or a jet mill. The method of grind | pulverizing to a predetermined particle size using a grinder is mentioned. In the latter method, excessive pulverization not only generates fine particles that easily scatter light, but also generates crystal defects on the particle surface, which may cause a decrease in luminous efficiency.
Moreover, you may provide the process of wash | cleaning fluorescent substance (baked material) as needed. After the cleaning step, the phosphor is dried until it has no adhering moisture and is used. Further, if necessary, dispersion / classification treatment may be performed to loosen the aggregation.

  From the viewpoint of obtaining a phosphor having excellent light emission characteristics, it is preferable that the content of impurities is small. In particular, since a large amount of halogen elements such as Cl and F tend to inhibit light emission, the total content of Cl and F is preferably 5000 ppm or less, more preferably 3000 ppm. Hereinafter, it is more preferably 2000 ppm or less.

<Phosphor composition>
The phosphor of this embodiment can be used alone as a light emitting material as it is, but can also be mixed with other materials and used as a phosphor composition. That is, the phosphor composition may include a substance different from the phosphor of the present embodiment. When used as a phosphor composition, the phosphor content of this embodiment is preferably 20% by mass or more, more preferably 30% by mass or more, and still more preferably 40% by mass or more, based on the total amount of the composition. . At this time, as a substance different from the phosphor of the present embodiment, a phosphor different from the phosphor of the present embodiment; addition reaction type silicone or condensation reaction type silicone resin, modified silicone resin, polycarbonate resin, epoxy resin, polyvinyl Binder resins and sealing resins such as glass-based resins, polyethylene-based resins, polypropylene-based resins, and polyester-based resins; glass; diffusing agents; thickeners; extenders; interfering agents, and the like, but are not particularly limited thereto.

<Light emitting device>
The phosphor of the present embodiment described above and the phosphor composition using the phosphor are suitably used as a light emitting material of a light emitting device such as a lighting device or an image display device. This type of light-emitting device includes at least a light source for excitation that emits light in the near ultraviolet or short-wavelength visible region, and a phosphor that converts at least part of the light emitted by this light source for excitation into a different emission spectrum, As such a phosphor, the phosphor of the present embodiment described above and a phosphor composition using the phosphor may be used. Known light emitting devices such as illumination devices and image display devices include LED devices such as LED illumination devices and LED image display devices, EL devices such as EL illumination devices and EL image display devices, and fluorescent lamps. More specifically, a white light emitting diode, a lighting fixture including a plurality of white light emitting diodes, a backlight for a liquid crystal panel, and the like can be given, but not limited thereto. Examples of the image display device include a fluorescent display tube (VFD), a field emission display (FED), a plasma display panel (PDP), a cathode ray tube (CRT), a liquid crystal display (LCD), and the like. Not.

  As the excitation light source, a light source that emits light in the near ultraviolet region to the blue region having a wavelength of 300 to 500 nm that matches the excitation peak (absorption maximum wavelength) of the phosphor of this embodiment is preferably used. Examples of such a light source include a light emitting diode (LED), a laser diode (LD), a semiconductor laser, or an organic EL light emitter (OLED) that emits light having a wavelength of 300 to 500 nm. Thereby, desired luminescent colors, such as green, yellowish green, yellow, and red, can be efficiently emitted from the phosphor.

  Hereinafter, the content of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist. In addition, the values of various production conditions and evaluation results in the following examples have meanings as preferred values of the upper limit or the lower limit in the embodiments of the present invention, and the preferred range is a preferred value of the above-described upper limit or lower limit. The preferable range may be a range defined by a combination of the above upper limit value or lower limit value and the values of the following examples or values of the examples.

<Measurement method>
[Luminescent characteristics]
The luminescent particles were collected, and the excitation emission spectrum and the emission spectrum were measured using a Xe spectral excitation apparatus QE1100 (manufactured by Otsuka Electronics Co., Ltd.) and a light emission detector MCPD-7700 (manufactured by Otsuka Electronics Co., Ltd.). Further, the emission peak wavelength and the half width of the emission peak were read from the obtained emission spectrum.
[Elemental analysis]
After selecting crystals by observation with a scanning electron microscope (SEM), each element was analyzed using an energy dispersive X-ray analyzer (EDX).
[Crystal structure analysis]
X-ray diffraction data of single crystal particles was measured with a single crystal X-ray diffractometer (Bruker AXS, D8 QUEST) equipped with an imaging plate and a graphite monochromator and using MoKα as an X-ray source. APEX2 was used to collect data and refine the lattice constant, and SADABS was used to correct X-ray shape absorption. For the data of F ² with a SHELXL-97 and Jana2006 The refinement of the crystal structure parameters. In addition, VESTA was used for drawing the crystal structure.
<Synthesis conditions>
Li ₃ N, Li ₂ O, Mg ₃ N ₂ , Sr ₃ N ₂ , SrO, AlN, Al ₂ O ₃ , EuN, Eu ₂ O ₃ , EuF ₃ are used as the phosphor raw material powder, and SrF ₂ powder is used as the flux. Using. The raw materials were weighed so as to have the masses shown in Table 3 and then put in a mortar and mixed until uniform, whereby the raw material mixed powders of Examples 1 to 5 and Reference Example 1 were obtained. Masses shown in Table 4 were collected from the obtained raw material mixed powders, and filled in containers made of molybdenum. These operations were all performed in a glove box filled with N ₂ gas.

Next, each container was placed in a tubular furnace, N ₂ gas was circulated, and baked at the temperatures and holding times shown in Table 5. The container after firing was introduced into a glove box filled with N ₂ gas, and pulverized the resultant product in a mortar to obtain a calcined powder of Examples 1 to 5 and Reference Example 1, respectively.

[Reference Example 1]
Columnar red particles were collected from the obtained fired powder of Reference Example 1 (phosphor of Reference Example 1). When the crystal structure analysis of the phosphor of Reference Example 1 was performed by single crystal X-ray diffraction measurement, the phosphor of Reference Example 1 belongs to the tetragonal system, belongs to the I 4 / m space group, and a = b = 1/17 crystal having a lattice constant of 8.07 [Å] and c = 3.31 [Å]. The phosphor of Reference Example 1 was a substance shown in Patent Document 6.
Subsequently, elemental analysis (EDX measurement) was performed on the phosphor of Reference Example 1. Table 6 shows the EDX measurement results and the calculated compositions obtained by normalizing them with Sr + Eu = 1. The detected elements were Sr, Mg, Al, Eu, N, O, and F. Li is not detected by EDX measurement.

Here, based on the crystal structure of the 1/1 crystal, the calculated composition using the following condition I is shown in Table 7. Similarly, Table 8 shows the calculated compositions using the following conditions I, II, and III based on the crystal structure of the 1/1 crystal.
Condition I: Li + Mg + Al = 4 when Sr + Eu = 1, Condition II: N + O = 4 when Sr + Eu = 1 Condition III: The values of N and O satisfy the electrical neutral conditions most
(Eu is calculated as divalent. F may be included a little,
Not taken into account in the calculation. )

As shown in Table 8, the calculated composition based on Conditions I, II and III was Sr _0.96 Li _0.59 Mg _0.98 Al _2.43 Eu _0.04 N _3.85 O _0.15 . From the calculated composition, it is suggested that the phosphor of Reference Example 1 is almost a nitride although it may contain a trace amount of O. The reason for the large difference between the measured values and calculated values of N and O is presumed to be due to the oxidation of the particle surface. Further, from the calculated composition obtained from the conditions I, II and III, it is presumed that the substitution of Mg is mainly represented by the reaction formula of Li + Al → 2Mg. Moreover, it is expected that the same amount of Mg solid solution is allowed in other FT substance groups.

  Next, the excitation / emission spectrum of the phosphor of Reference Example 1 is shown in FIG. The excitation spectrum of the phosphor of Reference Example 1 is a measurement result when the emission of 685 nm is monitored and the emission spectrum is excited using a light source of 492 nm. The phosphor of Reference Example 1 emitted red light having an emission peak wavelength of 685 nm and a half-value width of 93 nm. Although the phosphor of Reference Example 1 showed strong light emission, it showed a wavelength with low visibility and was not preferable.

[Example 1]
Fragmented yellow particles were collected from the obtained fired powder of Example 1 (phosphor of Example 1). When the crystal structure analysis of the phosphor of Example 1 was performed by single crystal X-ray diffraction measurement, the phosphor of Example 1 belongs to the tetragonal system, belongs to the I 4 / m space group, and Table 9 It was a 6/7 crystal occupying the crystal parameters and atomic coordinates shown. Further, the crystal composition in the case of not containing Eu was Sr ₆ Li ₂₀ Al ₈ O ₂₈ , and when Sr = 1, it was Sr ₁ Li _3.33 Al _1.33 O _4.67 .

  Furthermore, the phosphor of Example 1 was subjected to elemental analysis (EDX measurement). Table 10 shows the EDX measurement results and the calculated compositions obtained by normalizing them with Sr + Eu = 6. The detected elements were Sr, Al, Eu, N, O, and Cl. Note that Li is not detected by EDX measurement, and Cl is considered to be mixed in the process of producing the fired powder.

Here, based on the crystal structure of the 6/7 crystal, the calculated composition using the following condition I is shown in Table 11. Similarly, Table 12 shows the calculated compositions using the following conditions I, II and III based on the crystal structure of the 6/7 crystal.
Condition I: Li + Al = 28 when Sr + Eu = 6 Condition II: N + O = 28 when Sr + Eu = 1 Condition III: Values of N and O are values that most satisfy the electrical neutral condition
(Eu is calculated as divalent. Cl may be included slightly,
Not taken into account in the calculation. )
From Table 11, it was confirmed that the cation composition value by the structural analysis and the cation composition value by the EDX measurement were in good agreement.
Table 12 suggests that the phosphor of Example 1 is almost an oxide although it may contain a trace amount of N.

  Next, FIG. 3 shows an emission spectrum when the phosphor of Example 1 was excited using a 365 nm light source. The phosphor of Example 1 emitted yellow light with an emission peak wavelength of 571 nm and a half-value width of 80 nm.

[Example 2]
Flat green particles were collected from the obtained fired powder of Example 2 (phosphor of Example 2). When the crystal structure analysis of the phosphor of Example 2 was performed by single crystal X-ray diffraction measurement, the phosphor of Example 2 belongs to the tetragonal system, belongs to the P 4 / n space group, and Table 13 It was an 11/13 crystal occupying the crystal parameters and atomic coordinates shown. Further, the crystal composition in the case of not containing Eu was Sr ₁₁ Li ₃₇ Al ₁₅ O ₅₂ , and when Sr = 1, it was Sr ₁ Li _3.36 Al _1.36 O _4.73 .

  Next, the excitation / emission spectrum of the phosphor of Example 2 is shown in FIG. The excitation spectrum of the phosphor of Example 2 is a measurement result when emission at 533 nm is monitored and the emission spectrum is excited using a 400 nm light source. The phosphor of Example 2 emitted green light with an emission peak wavelength of 533 nm and a half width of 68 nm.

[Example 3]
The calcined powder of Example 3 was taken out of the container, and flat green particles adhering to the container wall surface at this time were collected (phosphor of Example 3). When the crystal structure analysis by single crystal X-ray diffraction measurement was performed on the phosphor of Example 3, the phosphor of Example 3 belongs to the tetragonal system, belongs to the P 4 / n space group, and Table 14 It was a 5/6 crystal occupying the crystal parameters and atomic coordinates shown. Further, the crystal composition in the case of not containing Eu was Sr ₅ Li ₁₇ Al ₇ O ₂₄ , and when Sr = 1, it was Sr ₁ Li _3.40 Al _1.40 O _4.80 .

  Next, FIG. 5 shows an emission spectrum when the phosphor of Example 3 was excited using a 365 nm light source. The phosphor of Example 3 emitted green light with an emission peak wavelength of 533 nm and a half-value width of 66 nm.

[Example 4]
The calcined powder of Example 4 was taken out of the container, and flat green particles adhering to the container wall surface at this time were collected (phosphor of Example 4). The phosphor of Example 4 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. As a result, the phosphor of Example 4 belongs to the tetragonal system, belongs to the P 4 / n space group, and Table 15 It was a 19/23 crystal occupying the crystal parameters and atomic coordinates shown. Further, the crystal composition in the case of not containing Eu was Sr ₁₉ Li ₆₅ Al ₂₇ O ₉₂ , and when Sr = 1, it was Sr ₁ Li _3.42 Al _1.42 O _4.84 .

  Further, the phosphor of Example 4 was subjected to elemental analysis (EDX measurement). Table 16 shows the EDX measurement results and the calculated compositions obtained by normalizing them with Sr + Eu = 19. The detected elements were Sr, Mg, Al, Eu, N, O, and F. Note that Li is not detected by EDX measurement, and Mg is considered to be mixed in the process of producing the fired powder.

Here, based on the crystal structure of the 19/23 crystal, the calculated composition using the following condition I is shown in Table 17. Similarly, based on the crystal structure of the 19/23 crystal, the calculated composition using the following conditions I, II and III is shown in Table 18.
Condition I: Li + Mg + Al = 92 when Sr + Eu = 19 Condition II: N + O = 92 when Sr + Eu = 19 Condition III: The values of N and O satisfy the electrical neutral conditions most
(Eu is calculated as divalent. F may be included a little,
Not taken into account in the calculation. )
From Table 17, it was confirmed that the cation composition value by the structural analysis and the cation composition value by the EDX measurement were in good agreement.
Table 18 suggests that the phosphor of Example 4 is almost an oxide although it may contain a trace amount of N.

  Next, the excitation / emission spectrum of the phosphor of Example 4 is shown in FIG. The excitation spectrum of the phosphor of Example 4 is a measurement result when the emission of 541 nm is monitored and the emission spectrum is excited using a light source of 406 nm. The phosphor of Example 4 emitted green light with an emission peak wavelength of 541 nm and a half width of 68 nm.

[Example 5]
The fired powder of Example 5 was taken out from the container, and massive green particles adhering to the container wall surface were collected at this time (phosphor of Example 5). The phosphor of Example 5 was subjected to crystal structure analysis by single crystal X-ray diffraction measurement. As a result, the phosphor of Example 5 belongs to the tetragonal system, belongs to the P 4 / n space group, and Table 19 14/17 crystals occupying the crystal parameters and atomic coordinates shown. Further, the crystal composition in the case of not containing Eu was Sr ₇ Li ₂₄ Al ₁₀ O ₃₄ , and when Sr = 1, it was Sr ₁ Li _3.43 Al _1.43 O _4.86 .

  Furthermore, elemental analysis (EDX measurement) was performed on the phosphor of Example 5. Table 20 shows the EDX measurement results and the calculated compositions obtained by normalizing them with Sr + Eu = 7. The detected elements were Sr, Mg, Al, Eu, N, O, and F. Note that Li is not detected by EDX measurement, and Mg is considered to be mixed in the process of producing the fired powder.

Here, based on the crystal structure of the 14/17 crystal, the calculated composition using the following condition I is shown in Table 21. Similarly, Table 22 shows the calculated compositions using conditions I, II and III based on the 14/17 crystal structure.
Condition I: Li + Mg + Al = 34 when Sr + Eu = 7 Condition II: N + O = 34 when Sr + Eu = 7 Condition III: The values of N and O satisfy the electrical neutral conditions most
(Eu is calculated as divalent. F may be included a little,
Not taken into account in the calculation. )
From Table 21, it was confirmed that the cation composition value by the structural analysis and the cation composition value by the EDX measurement were in good agreement.
Table 22 suggests that the phosphor of Example 5 is almost an oxide although it may contain a trace amount of N.

  Next, FIG. 7 shows an emission spectrum when the phosphor of Example 5 was excited using a 365 nm light source. The phosphor of Example 5 emitted green light with an emission peak wavelength of 529 nm and a half width of 69 nm.

<General description>
[General lattice constant in FT substance group]
Table 23 shows the lattice constant a and the lattice constant c obtained from the single crystal X-ray structural analysis of the phosphors of Reference Example 1 and Examples 1 to 5. Since the phosphors of Reference Example 1 and Examples 1 to 5 have a crystal structure belonging to a tetragonal system, the lattice constant a = lattice constant b.

FIG. 8 shows the value of the lattice constant a of the phosphors of Reference Example 1 and Examples 1 to 5 with respect to the n value. The average value of the lattice constant a was 7.8875 [Å].
Moreover, the value of the lattice constant c of the fluorescent substance of the reference example 1 and Examples 1-5 with respect to n value is shown in FIG. In addition, FIG. 9 shows an approximate straight line obtained by the method of least squares when the intercept is zero. The linear formula of the approximate straight line was y = 3.1760x. Moreover, R2 value which shows linearity was 1.0000.

  Table 24 shows the result of estimating the general lattice constant of the FT substance group based on these. Here, n = 1, 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28, respectively, 1/1 crystal, 4/5 Crystal, 5/6 crystal, 6/7 crystal, 7/8 crystal, 8/9 crystal, 9/11 crystal, 11/13 crystal, 13/15 crystal, 13/16 crystal, 14/17 crystal, 16/19 The lattice constant c of the crystal, 17/20 crystal, 17/21 crystal, 19/23 crystal, 22/27 crystal, and 23/28 crystal is shown.

[Composition in FT substance group]
Table 25 shows the compositions obtained from the structural analysis of Examples 2 and 3, and the calculated compositions obtained from the EDX measurements of Reference Example 1, Example 1, Example 4, and Example 5.

  As shown in Table 25, the solid solution of Mg is noticeable in Reference Example 1, but it is considered possible in other FT substance groups. In any of the FT substance groups, it is considered that the N and O composition ratio can be adjusted. Furthermore, there is a possibility that halogen elements such as F and Cl are included as some impurities.

The phosphor of the present invention has a crystal structure and emission characteristics different from those of conventional phosphors, and emits green to yellow light by light in the near ultraviolet or short wavelength visible region. In addition, it can be widely and effectively used as a fluorescent material used in various applications such as an image display device.

Claims (31)

M element, A element, Li, and C element (where M element is an active element, A element is at least one element selected from the group consisting of Ca, Sr, and Ba, and C element is Al and / or A crystal phase having at least N and / or O.
A phosphor having a lattice constant satisfying the following range in the crystalline phase.
7.10 ≦ lattice constant a ≦ 8.68
7.10 ≦ lattice constant b ≦ 8.68
2.86 × n ≦ lattice constant c ≦ 3.49 × n
(In the above formula, n is any one integer selected from 5, 6, 7, 8, 9, 11, 13, 15, 16, 17, 19, 20, 21, 23, 27, and 28. (Note that the ranges of the lattice constant c specified by n may overlap.) The phosphor according to claim 1, wherein at least Li and C elements are present at the same crystal site, and the crystal system is a tetragonal system. The phosphor according to claim 1 or 2, further comprising Mg and / or E element (wherein E element is at least one element selected from the group consisting of Si and Ge). The phosphor according to claim 3, comprising a crystal phase represented by the following formula [1].
M _a A _1-a Li _b-d1 C _c-d2-e Mg _{d1 + d2} E _e N _f O _g [1]
(In the above formula [1], a, b, c, d1, d2, e, f, and g are values that satisfy the following formula independently.
0 <a ≦ 0.2
1.0 ≦ b ≦ 3.5
1.0 ≦ c ≦ 4.0
0 ≦ d1 ≦ 3.5
0 ≦ d2 ≦ 4.0
0 ≦ e ≦ 4.0
0 ≦ f ≦ 5.0
0 ≦ g ≦ 5.0
4.0 ≦ b + c ≦ 5.0
4.0 ≦ f + g ≦ 5.0
0 ≦ b−d1
0 ≦ c-d2-e) 5. The phosphor according to claim 4, wherein 0 ≦ d1 ≦ 0.6, 0 ≦ d2 ≦ 0.6, and 0 ≦ e ≦ 1.0 in the formula [1]. 6. In the above formula [1], 4.5 ≦ b + c ≦ 5.0, 0 ≦ d1 + d2 ≦ 1.0, and 4.5 ≦ f + g ≦ 5.0. The phosphor according to 1. The phosphor according to any one of claims 1 to 6, wherein the crystal phase includes a crystal phase represented by the following formula [2].
_{M a 'A m / n-} a' Li x-y1 C 4-x-y2-z Mg y1 + y2 E z N 4 + 2m / n-2x + y1-y2 + z O 2x-y1 + y2-z-2m / n [2]
(In said formula [2], a ', m, n, x, y1, y2, and z are values which satisfy | fill the following formula each independently.
0 <a ′ ≦ 0.2 × m / n
4/5 ≦ m / n ≦ 8/9
m / n ≦ x ≦ 2 + m / n
0 ≦ y1 ≦ 0.6
0 ≦ y2 ≦ 0.6
0 ≦ y1 + y2 ≦ 1.0
0 ≦ z ≦ 1.0
0 ≦ xy
0 ≦ 4-x−y2−z) The fluorescence according to any one of claims 1 to 7, wherein the M element contains at least one element selected from the group consisting of Eu, Ce, Pr, Sm, Tb, Dy, and Yb. body. 9. n is any one integer selected from 6, 7, 8, 11, 13, 15, 17, 19, 20, 23, 27, and 28. The phosphor according to claim 1. In the above formula [2], 22/27 ≦ m / n ≦ 7/8, and 0.5 × m / n + 0.5 × (2 + m / n) ≦ x ≦ 2 + m / n. Item 10. The phosphor according to any one of Items 7 to 9. 11. The phosphor according to claim 7, wherein 0 ≦ y1 + y2 ≦ 0.1 and 0 ≦ z ≦ 0.1 in the formula [2]. The phosphor according to claim 1, wherein the M element includes Eu, the A element includes Sr, and the C element includes Al. E element contains Si, The fluorescent substance as described in any one of Claims 3-12 characterized by the above-mentioned. 14. The phosphor according to claim 1, wherein n is any one integer selected from 6, 7, 13, 17, and 23. In the formula [2], 14/17 ≦ m / n ≦ 6/7, and 0.25 × m / n + 0.75 × (2 + m / n) ≦ x ≦ 2 + m / n. Item 15. The phosphor according to any one of Items 7 to 14. The phosphor according to any one of claims 3 to 15, wherein the M element includes Eu, the A element includes Sr, the C element includes Al, and the E element includes Si. In said formula [2], n is 6, It is 0.05 * m / n + 0.95 * (2 + m / n) <= x <= 2 + m / n, The any one of Claims 7-16 characterized by the above-mentioned. The phosphor according to Item. 18. The phosphor according to claim 17, wherein m is 5 and n is 6 in the formula [2]. In said formula [2], n is 7, It is 0.05 * m / n + 0.95 * (2 + m / n) <= x <= 2 + m / n, The any one of Claims 7-16 characterized by the above-mentioned. The phosphor according to Item. 20. The phosphor according to claim 19, wherein m is 6 and n is 7 in the formula [2]. In said formula [2], n is 13, It is 0.05 * m / n + 0.95 * (2 + m / n) <= x <= 2 + m / n, The any one of Claims 7-16 characterized by the above-mentioned. The phosphor according to Item. The phosphor according to claim 21, wherein in the formula [2], m is 11 and n is 13. In said formula [2], n is 17, It is 0.05 * m / n + 0.95 * (2 + m / n) <= x <= 2 + m / n, The any one of Claims 7-16 characterized by the above-mentioned. The phosphor according to Item. 24. The phosphor according to claim 23, wherein m is 14 and n is 17 in the formula [2]. In said formula [2], n is 23, It is 0.05 * m / n + 0.95 * (2 + m / n) <= x <= 2 + m / n, The any one of Claims 7-16 characterized by the above-mentioned. The phosphor according to Item. 26. The phosphor according to claim 25, wherein m is 19 and n is 23 in the formula [2]. Further comprising F and / or Cl;
27. The phosphor according to any one of claims 1 to 26, wherein the content ratios of F and Cl in terms of element amount are 5000 ppm or less in total. A phosphor composition comprising the phosphor according to any one of claims 1 to 27, wherein the phosphor is contained in an amount of 20% by mass or more based on the total amount. An excitation light source that emits light in the near ultraviolet or short wavelength visible region, and at least a phosphor that converts at least part of the light emitted by the excitation light source into a different emission spectrum,
The phosphor includes at least the phosphor according to any one of claims 1 to 27 and / or the phosphor composition according to claim 28,
Light emitting device. A light emitting device according to claim 29 is provided.
Lighting device. A light emitting device according to claim 29 is provided.
Image display device.