Fluorescent ceramics and light-emitting devices containing the phosphor ceramics

Abstract

Fluorescent ceramic containing a first component which emits in the range from ≥ 500 to ≤ 650 nm and a second component which absorbs in the range from ≥ 500 to ≤ 650 nm and emits in the range from ≥ 900 to ≤ 1000 nm; wherein the first component is a material selected from the group consisting of (M I 1-x-y M II x M III y )3(M IV 1-z M V z )5O 12 with M I = Y, Lu, Tb; M II = Gd, Yb; M III = Ce, Pr, Yb; M IV = Al; M V = Ga, Sc and 0.0 ≤ x ≤ 1.0; 0.0 ≤ y ≤ 0.1; 0.0 ≤ z ≤ 1.0 or (La 1-x Y x )3Si6N 11 :Ce, ß-SiAlON:Eu, (Ca 1-x Sr x )Sc2O4:Ce, La(Ba 1-x Sr x )2AlO5:Ce 3+ (Ba 1-x Sr x )(Y 1-x Lu x )2Al4SiO 12 :Ce 3+ , (Ba 1-x Si x )2SiO4:Eu 2+, Li2BaSiO4:Eu 2+ , RbLi(Li3SiO4)2:Eu 2+ , (Ba 1-x-y ,Sr x Ca y )Si2O2N2:Eu 2+ , Ca7(PO4)2(SiO4)2:Eu 2+ , Ca2BO3Cl:Eu 2+ , Ba2LiSi7N 11 :Eu 2+ , (Ba 1-x-y Sr x Ca y )LnSi4N7:Eu 2+ (Ln = Y, La, Gd, Lu), Ca2Al3O6F:Eu 2+ , Ba2LiSi7AlN 12 :Eu 2+ or Ca3Si2O4N2:Eu 2+ with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof; and wherein the second component is a material selected from the group consisting of Mg2SiO4:Cr, (Y 1-x-y Gd x Lu y )Al3(BO3)4:Cr, (Y 1-x-y-z La x Gd y Lu z )3(Al 1- a Ga a )5O 12 :Cr, (Ca 1-x Sr x )Sc2O4:Cr, Ca3(Sc 1-x Ga x )2Si3O 12 :Cr, La3Ga5GeO 14 :Cr, (Y 1-x- y Gd x La y )AlO3:Cr, (Ca 1-x- ySr y Bay )CuSi4O 10 or (Ca 1-x-y Sr y Ba y )CuGe4O 10 , La2MgZrO6:Cr 3+ , Mg3Ga2GeO8:Cr 3+ , BaZrSi3O9:Cr 3+ , K2Ga2Sn6O 16 :Cr 3+ , Mg 14 Ge5O 24 :Cr 3+ ,Cr 4+ , LiScP2O7:Cr 3+ , Ca2LuZr2Al3O 12 :Cr 3+ , K3LuSi2O7:Eu 2+ , LaMgGa 11 O 19 :Cr 3+ , Ca2LuScGa2Ge2O 12 :Cr 3+ , Ba3(PO4)2:Mn 5+ , LiInSiO4:Cr 3+ , ScBO3:Cr 3+ or MgAl2O4:Mn 2+ with x, y, z, a = 0.0 - 1.0 and mixtures thereof.

Description

[0001] The present invention relates to phosphor ceramics and light-emitting devices containing such phosphor ceramics which are capable of emitting in both the visible and NIR ranges.

[0002] Broadband NIR emitters are required in the fields of analytics, medical technology, spectroscopy, biotechnology, food technology, and quality control. Until now, incandescent or halogen lamps have been used for these applications, which, despite their relatively short lifetime and low efficiency, have been very cost-effective due to high production volumes.

[0003] However, the task arises, particularly given the fact that incandescent or halogen lamps have not been placed on the market in the EU since 2012, except for special applications, of providing alternative broadband phosphors and systems containing such phosphors.

[0004] Phosphors are known, among others, from DE 10 2017 120 681 A1, US 2018 / 0 171 225 A1 and US 2010 / 0 012 964 A1.

[0005] This object is solved by claim 1 of the present application.

[0006] Accordingly, a phosphor ceramic is proposed, comprising a first component (hereinafter also referred to as “component 1”) which emits in the range from ≥500 to ≤650 nm and a second component (hereinafter also referred to as “component 2”) which absorbs in the range from ≥500 to ≤650 nm and emits in the range from ≥900 to ≤1000 nm; wherein the first component is a material selected from the group consisting of (M I 1-x-y -M II x M III y )3(M IV 1-z M V z )5O 12 with M I = Y, Lu, Tb; M II = Gd, Yb; M III = Ce, Pr, Yb; M IV = Al; M V= Ga, Sc and 0.0 ≤ x ≤ 1.0; 0.0 ≤ y ≤ 0.1; 0.0 ≤ z ≤ 1.0 or (La 1-x Y x )3Si6N 11 :Ce, ß-SiAlON:Eu, (Ca 1-x Sr x )Sc2O4:Ce, La(Ba 1-x Sr x )2AlO5:Ce 3+ (Ba 1-x Sr x )(Y 1-x Lu x )2Al4SiO 12 :Ce 3+ , (Ba 1-x Si x )2SiO4:Eu 2+ , Li2BaSiO4:Eu 2+ , RbLi(Li3SiO4)2:Eu 2+ , (Ba 1-x-y ,Sr x Ca y )Si2O2N2:Eu 2+ , Ca7(PO4)2(SiO4)2:Eu 2+ , Ca2BO3Cl:Eu 2+ , Ba2LiSi7N 11 :Eu 2+ , (Ba 1-x-y Sr x Ca y )LnSi4N7:Eu 2+ (Ln = Y, La, Gd, Lu), Ca2Al3O6F:Eu 2+ , Ba2LiSi7AlN 12 :Eu 2+ or Ca3Si2O4N2:Eu 2+ with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof; and wherein the second component is a material selected from the group consisting of Mg2SiO4:Cr, (Y 1-x-y<h2 style=";text-align:left;direction:ltr">Gd<h2 style=";text-align:left;direction:ltr"> x <h2 style=";text-align:left;direction:ltr"> Lu<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> )Al3(BO3)4:Cr, (Y<h2 style=";text-align:left;direction:ltr"> 1-x-y-z <h2 style=";text-align:left;direction:ltr"> No<h2 style=";text-align:left;direction:ltr"> x <h2 style=";text-align:left;direction:ltr"> Gd<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> Lu<h2 style=";text-align:left;direction:ltr"> z <h2 style=";text-align:left;direction:ltr"> 3(Al)<h2 style=";text-align:left;direction:ltr"> 1-a <h2 style=";text-align:left;direction:ltr"> Ga<h2 style=";text-align:left;direction:ltr"> a <h2 style=";text-align:left;direction:ltr"> 5O)<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> :Cr, (Ca<h2 style=";text-align:left;direction:ltr"> 1-x <h2 style=";text-align:left;direction:ltr"> Sr<h2 style=";text-align:left;direction:ltr"> x <h2 style=";text-align:left;direction:ltr"> Sc2O4:Cr, Ca3(Sc)<h2 style=";text-align:left;direction:ltr"> 1-x <h2 style=";text-align:left;direction:ltr"> Ga<h2 style=";text-align:left;direction:ltr"> x <h2 style=";text-align:left;direction:ltr"> )2Si3O<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> :Cr, La3Ga5GeO<h2 style=";text-align:left;direction:ltr"> 14 <h2 style=";text-align:left;direction:ltr"> :Cr, (Y<h2 style=";text-align:left;direction:ltr"> 1-x-y <h2 style=";text-align:left;direction:ltr"> Gd<h2 style=";text-align:left;direction:ltr"> x <h2 style=";text-align:left;direction:ltr"> No<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> )AlO3:Cr(Ca<h2 style=";text-align:left;direction:ltr"> 1-x-y <h2 style=";text-align:left;direction:ltr"> Sr<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> Ba<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> CuSi4O<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> or (Ca<h2 style=";text-align:left;direction:ltr"> 1-x-y <h2 style=";text-align:left;direction:ltr"> Sr<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> Ba<h2 style=";text-align:left;direction:ltr"> y <h2 style=";text-align:left;direction:ltr"> CuGe4O<h2 style=";text-align:left;direction:ltr"> 10 <h2 style=";text-align:left;direction:ltr"> , La2MgZrO6:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , Mg3Ga2GeO8:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , BaZrSi3O9:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , K2Ga2Sn6O<h2 style=";text-align:left;direction:ltr"> 16 <h2 style=";text-align:left;direction:ltr"> :Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , Mg<h2 style=";text-align:left;direction:ltr"> 14 <h2 style=";text-align:left;direction:ltr"> Ge5O<h2 style=";text-align:left;direction:ltr"> 24 <h2 style=";text-align:left;direction:ltr"> :Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> ,Cr<h2 style=";text-align:left;direction:ltr"> 4+ <h2 style=";text-align:left;direction:ltr"> , LiScP2O7:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , Ca2LuZr2Al3O12:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , K3LuSi2O7:Eu<h2 style=";text-align:left;direction:ltr"> 2+ <h2 style=";text-align:left;direction:ltr"> , LaMgGa<h2 style=";text-align:left;direction:ltr"> 11 <h2 style=";text-align:left;direction:ltr"> O<h2 style=";text-align:left;direction:ltr"> 19 <h2 style=";text-align:left;direction:ltr"> :Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , Ca2LuScGa2Ge2O<h2 style=";text-align:left;direction:ltr"> 12 <h2 style=";text-align:left;direction:ltr"> :Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , Ba3(PO4)2:Mn<h2 style=";text-align:left;direction:ltr"> 5+ <h2 style=";text-align:left;direction:ltr"> , LiInSiO4:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> , ScBO3:Cr<h2 style=";text-align:left;direction:ltr"> 3+ <h2 style=";text-align:left;direction:ltr"> or MgAl2O4:Mn<h2 style=";text-align:left;direction:ltr"> 2+with x, y, z, a = 0.0 - 1.0 and mixtures thereof.

[0007] Surprisingly, it has now been discovered that such a ceramic can be produced that emits broadband light in both the visible and near-infrared ranges. At the same time, the fact that the second component absorbs in the emission range of the first component allows for precise adjustment of the overall emission of the ceramic.

[0008] In particular, the phosphor ceramic according to the invention based on at least one of the following advantages can be achieved in most applications: - The phosphor ceramic exhibits higher stability, thermal quenching temperature, and, due to its lower pore density, better thermal conductivity than systems using bulk phosphor, allowing primary radiation with relatively high energy densities to be used for excitation. This is an advantageous embodiment of the present invention, as will be shown below. - The materials show higher photostability and linearity compared to conventional fluorescent systems. - The phosphor ceramic has both a very broadband emission spectrum in the visible and near infrared range, and the property that, through excitation with high energy density—for example, with a laser—light with very high luminance can be generated. This luminance is significantly higher than that possible with conventional halogen light sources. This luminance is in a range that, according to the state of the art, can only be generated in a very narrow band with conventional LEDs with a single wavelength (half-width of approximately 20 nm) or with laser-driven plasma light sources, which are very complex and expensive. The combination of high luminance and broadband is particularly advantageous for spectroscopy applications, particularly transmission spectroscopy. The wavelength range from 500 to 1000 nm is also particularly suitable for transmission spectroscopy. For example, information about sugar, water, and fat content can be obtained. The lower NIR range up to approximately 1100 nm can be detected with silicon-based detectors (advantage: high efficiency, mass production—therefore cost-effective). There are numerous applications in the pharmaceutical and food industries (quality assurance). The combination of high luminance and broadband is also interesting for mobile applications where point-based, energy-saving measurements are required. The invention is particularly suitable for hyperspectral imaging. This is often done using a scanning method (line scanners, each responsible for different wavelengths). The light source according to the invention is particularly suitable for generating the bright line light required for this type of imaging.

[0009] The term “fluorescent ceramic” in the sense of the present invention means in particular a ceramic which consists essentially of light-emitting materials.

[0010] The term “essentially” in the sense of the present invention means and / or includes a proportion of ≥ 95% (vol.% / vol.%), more preferably ≥ 98% (vol.% / vol.%) and most preferably ≥ 99 (vol.% / vol.%).

[0011] The term “ceramic” in the sense of the present invention means and / or includes in particular a compact crystalline or polycrystalline material with a controlled amount of pores or pore-free.

[0012] The term "polycrystalline material" within the meaning of the present invention means and / or includes, in particular, a material with a volume density of greater than 90 percent of the main component, consisting of more than 80 percent individual crystal domains, each crystal domain having a diameter of 0.1-20 µm and a different crystallographic orientation. The individual crystal domains can be interconnected or diluted via amorphous or glassy material or via additional crystalline phases.

[0013] The term ‘emitting in the range ≥X to ≤Y’ means and / or includes that the material in question has an emission band in that range; this may, but need not, be the main emission band.

[0014] The term “absorbing in the range ≥X to ≤Y” means and / or includes that the material in question absorbs radiation in this range and possibly converts it into low-energy radiation, which is then emitted in turn.

[0015] According to a preferred embodiment of the present invention, the crystalline material and / or the luminescent ceramic has a density of ≥ 90% to ≤ 100% of the theoretical density. This has proven advantageous for many applications of the present invention.

[0016] The first component contains a material selected from the group containing (M I 1-x-y -M II x M III y )3(M IV1-z M V z )5O 12 myth M I = Y, Lu, Tb; M II = Gd, Yb; M III = Ce, Pr, Yb; M IV = Al; M V = Ga, Sc where 0.0 ≤ x ≤ 1.0; 0.0 ≤ y ≤ 0.1; 0.0 ≤ z ≤ 1.0 oder (La 1-x Y x )3Si6N 11 :Ce, ß-SiAlON:I, (Ca 1-x Sr. x )Sc2O4:Ce, La(Ba 1-x Sr. x )2AlO5:Ce 3+ (Yes 1-x Sr. x )(Y 1-x IU x )2Al4SiO12:Ce 3+ , (Ba 1-x And x )2SiO4:I 2+ , Li2BaSiO4:I 2+ , RbLi(Li3SiO4)2:Iu 2+ , (Ba 1-x-y ,Sr. x That y )Si2O2N2:I 2+ , Ca7(PO4)2(SiO4)2:Iu 2+ , Ca2BO3Cl:I 2+ , Ba2LiSi7N 11 :I 2+ , (Ba 1-x-y Sr. x That y )LnSi4N7:I 2+ (Ln = Y, La, Gd, Lu), Ca2Al3O6F:Eu 2+ , Ba2LiSi7AlN 12 :I 2+ or Ca3Si2O4N2:Iu 2+with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof. Preferably, the first component consists essentially of the following:

[0017] Particularly preferred materials are selected from the group containing (M I 1-x-y -M II x M III y )3(M IV 1-z M V z )5O 12 with M I = Y, Lu, Tb; M II = Gd, Yb; M III = Ce, Pr, Yb; M IV = Al; M V = Ga, Sc and 0.0 ≤ x ≤ 1.0; 0.0 ≤ y ≤ 0.1; 0.0 ≤ z ≤ 1.0 or (La 1-x Y x )3Si6N 11 :Ce, ß-SiAlON:Eu, (Ca 1-x Sr x )Sc2O4:Ce or mixtures thereof.

[0018] These materials have proven particularly effective in practice.

[0019] The second component contains a material selected from the group containing Ti 3+ , V 3+ , V 4+ , Cr 3+ , Cr 4+ , Mn 4+ , Fe2+ , Faith 3+ , Co 2+ , Nor 2+ or Cu 2+ activated oxides, particularly from Mg2SiO4:Cr, (Y 1-x-y Gd x Lu y )Al3(BO3)4:Cr, (Y 1-x-y-z The x Gd y Lu z )3(Al 1-a Ga a )5O 12 :Cr, (Ca 1-x Sr x )Sc2O4:Cr, Ca3(Sc 1-x Ga x )2Si3O 12 :Cr, La3Ga5GeO 14 :Cr, (Y 1-x-y Gd x The y )AlO3:Cr(Ca 1-x-y Sr y Ba y )CuSi4O 10 odor (Ca 1-x-y Sr y Ba y )CuGe4O 10 , La2MgZrO6:Cr 3+ , Mg3Ga2GeO8:Cr 3+ , BaZrSi3O9:Cr 3+ , K2Ga2Sn6O 16 :Cr 3+ , Mg 14 Ge5O 24 :Cr 3+ ,Cr 4+ , LiScP2O7:Cr 3+ , Ca2LuZr2Al3O12:Cr 3+ , K3LuSi2O7:Eu 2+ , LaMgGa 11 OH 19 :Cr 3+ , Ca2LuScGa2Ge2O 12 :Cr 3+, Ba3(PO4)2:Mn 5+ , LiInSiO4:Cr 3+ , ScBO3:Cr 3+ or MgAl2O4:Mn 2+ with x, y, z, a = 0.0 - 1.0 and mixtures thereof. Preferably, the second component consists essentially of

[0020] Particularly preferred materials are selected from the group containing Mg2SiO4:Cr, (Y 1-x-y Gd x Lu y )Al3(BO3)4:Cr, (Y 1-x-y-z La x Gd y Lu z )3(Al 1-a Ga a )5O 12 :Cr, (Ca 1-x Sr x )Sc2O4:Cr, Ca3(Sc 1-x Ga x )2Si3O 12 :Cr, La3Ga5GeO 14 :Cr, (Y 1-x-y Gd x La y )AlO3:Cr(Ca 1-x-y Sr y Ba y )CuSi4O 10 or (Ca 1-x-y Sr y Ba y )CuGe4O 10 and mixtures thereof.

[0021] These materials have proven particularly effective in practice.

[0022] In particular, it has been found that when materials as described above are selected as the first component and as the second component, in most applications no or only negligible reactions between the materials are observed during the production of the ceramic, which represents a further advantage of the present invention.

[0023] According to a preferred embodiment of the invention, the phosphor ceramic comprises a third component (hereinafter also referred to as "component 3") that emits in the range of ≥650 to ≤900 nm. This has proven advantageous for many applications, as it allows for even more complete broadband emission.

[0024] According to a preferred embodiment, the third component contains a material selected from the group consisting of (Ca 1-x Sr x )Sc2O4:Eu, (Ca 1-x Sr x )O:Eu, (Ca 1-x Sr x)AlSiN3:Eu, (Ca 1-x-y Mr. x Ba y )2Si5N8:Eu, (Ca 1-x-y Mr. x Ba y )2Si 5-y Al y N 8-y THE y :I, (Ba 1-x Mr. x )3ScB3O9:Eu 2+ , K3ScSi2O7:Eu 2+ , (Ba 1-x-y Mr. x Here y )LiAl3N4:Eu 2+ , (Mr. 1-x Here x )4(PO4)2O:I 2+ , Rb3YSi2O7:Eu 2+ , (Mr. x Here 1-x )SiO4:Eu 2+ , (Ba 1-x Here x )4Si6ON 10 :I 2+ , (Ba 1-x Mr. x )4LiAl 11 N 14 :I 2+ , Rb3YSi2O7:Eu 2+ , (Y 1-x Lu x )4(Ba 1-x Mr. x )2Si9N 16 O2: Me 2+ , Mr2BeAl3N5:I 2+ , Li2(Sr 1-x Here x )2Mg2Si2N6:Eu 2+ , BaCa2Y6O 12 :Ce 3+ oder Sr3Sc4O9:Ce 3+with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof. Preferably, the third component consists essentially of

[0025] Particularly preferred materials are selected from the group containing (Ca 1-x Sr x )Sc2O4:Eu, (Ca 1-x Sr x )O:Eu, (Ca 1-x Sr x )AlSiN3:Eu and mixtures thereof.

[0026] According to a preferred embodiment of the invention, the phosphor ceramic comprises a fourth component (hereinafter also referred to as "component 4") that emits in the range of ≥420 to ≤500 nm. This has proven advantageous for many applications, as it allows for even more complete broadband emission.

[0027] According to a preferred embodiment, the fourth component contains a material selected from the group consisting of Na3(Rb 1-x Cs x )Mg7(PO4)6:Eu, Sr6BPsO 20 :Eu, BaAl2Si2O8:Eu, (Ca 1-x Srx )Al2O4:Eu, (Ca 1-x Mr. x )2MgSi2O7:Eu, (Ca 1-x Mr. x )3MgSi2O8:Eu, Ba5SiO4Br6:Eu, (Ba 1-x Mr. x )MgAl 10 THE 17 :I, (Y 1-x Gd x )2SiO5:Ce, (Y 1-x Gd x )BO3:Ce, (Sr 1-x Ba x )5(PO4)3Cl:Eu, (Na 1-x I read x )SrPO4:I 2+ , Mr2P2O7:I 2+ , Sr2ZnSi2O7:Eu 2+ , K2Al2B2O7:Eu 2+ , RbNa3(Li3SiO4)4:Eu 2+ , (Ba 1-x Mr. x )Li2Be4O6:Eu 2+ , SrB2O4:I 2+ , KBaYSi2O7:Eu 2+ , BaAl2Si2O8:Eu 2+ , (Ba 1-x-y Mr. x Here y )8Mg7Si9N 22 :I 2+ , Sr3Al 10 SiO 20 :I 2+ , SrMg2Al 16 THE 27 :I 2+ order Na(Ba 1-x Mr. x )BO3:Ce 3+ mit x = 0.0 - 1.0 and y = 0.0 - 1.0 and Mischungen daraus. Bevorzugt besteht die vierte Komponente im Wesentlichen daraus.

[0028] Particularly preferred materials are selected from the group containing Na3(Rb 1-x Cs x )Mg7(PO4)6:Eu, Sr6BPsO 20 :Eu, BaAl2Si2O8:Eu, (Ca 1-x Sr x )Al2O4:Eu, (Ca 1-x Sr x )2MgSi2O7:Eu, (Ca 1-x Sr x )3MgSi2O8:Eu, Ba5SiO4Br6:Eu, (Ba 1-x Sr x )MgAl 10 O 17 :Eu and mixtures thereof.

[0029] According to a preferred embodiment of the invention, components 1 and 2 are selected from the following lists: Component 1 Component 2 (Y,Gd,Tb,Lu)3(Al,Ga,Sc)5O 12 :What 3+ (Ca,Sr,Ba)Cu(Si,Ge)4O 10 (Ca,Mg,Y)3(Al,Sc,Si)5O 12 :What 3+ (Ca,Sr)Sc2O4:Cr 3+

[0030] According to a preferred embodiment of the invention, components 1 and 2 are selected from the following lists: Component 1 Component 2 (Y,Gd,Tb,Lu)3(Al,Ga,Sc)5O 12 :Ce 3+ ,Cr 3+ (Ca,Sr,Ba)Cu(Si,Ge)4O 10 (Ca,Mg,Y)3(Al,Sc,Si)5O 12 :What 3+ ,Cr 3+ (Ca,Sr)Sc2O4:Cr 3+

[0031] According to a preferred embodiment of the invention, components 1 to 3 are selected from the following lists: Component 1 Component 2 Component 3 (Y,Gd,Tb,Lu)3(Al,Ga,Sc)5O 12 :What 3+ (Y,Gd,Lu)3(Ga,Sc)5O 12 :Cr 3+ (Ca,Sr,Ba)Cu(Si,Ge)4O 10 (Ca,Mg,Y)3(Al,Sc,Si)5O 12 :What 3+ (Ca,Y)3(Al,Sc,Si)5O 12 :Cr 3+ (Ca,Sr)Sc2O4:Cr 3+

[0032] According to a preferred embodiment of the invention, components 1 to 3 are selected from the following lists: Component 1 Component 2 Component 3 (Y,Gd,Tb,Lu)3(Al,Ga,Sc)5O 12 :Ce 3+ ,Cr 3+ (Ca,Sr)Sc2O4:I 2+ (Ca,Sr,Ba)Cu(Si,Ge)4O 10 (Ca,Mg,Y)3(Al,Sc,Si)5O 12 :What 3+ ,Cr 3+ (Ca,Sr)O:I 2+ (Ca,Sr)Sc2O4:Cr 3+

[0033] The present invention also relates to a process for producing a luminous ceramic according to the invention, comprising the steps: a) Providing a mixture containing at least components 1 and 2, preferably in powder form, b) pressing the mixture under increased pressure and optionally at elevated temperature; and c) Optional sintering or heating.

[0034] The individual steps are briefly explained below, whereby all advantageous configurations can be combined ad libitum: Step a)

[0035] Preferably, the starting materials for the production of the ceramic are provided in powder form.

[0036] According to a preferred embodiment of the invention, the method additionally comprises a step a1) which can be carried out before or after step a): Step a1) Coating at least one component with an oxidic material, preferably containing, more preferably essentially consisting of a material selected from the group containing Al2O3, Y2O3, Gd2O3, Lu2O3, GdAlO3, GdMgAl 11 O 19 , Y3Al5O 12 , Gd3Al5O 12 , Lu3Al5O 12 , MgO or MgAl2O4 and mixtures thereof.

[0037] This has proven to be useful in many applications of the present invention, as it allows the reactivity of the components among each other to be further reduced.

[0038] According to a preferred embodiment of the invention, the mixture additionally comprises a small amount of an organic material, preferably a primary or secondary C1-C6 alcohol. Amyl alcohol (1-pentanol) is particularly preferred. Step b)

[0039] Step b) is carried out at elevated pressure, particularly preferably a pressure of ≥ 0.1 to ≤ 2 GPa, even more preferably ≥ 0.2 to ≤ 1 GPa.

[0040] The pressing time depends on the size of the ceramic; it is preferably pressed until the desired density is reached, preferably from ≥ 90% to ≤ 100% of the theoretical density. Step c)

[0041] Optionally, step b) is followed by a further step in which the resulting ceramic is heated and / or sintered. Depending on the application, step b) can be carried out in air, under inert gas (preferably nitrogen), or under forming gas. Preferred temperatures are ≥700 to ≤1300 °C, more preferably ≥800 to ≤1110 °C

[0042] Preferably, step c) is carried out for a duration of ≥1 to ≤ 24 h, more preferably ≥ 2 to ≤ 12 h and most preferably ≥ 4 to ≤ 8 h.

[0043] The present invention also relates to a light-emitting device comprising a phosphor ceramic according to the invention.

[0044] According to a preferred embodiment of the invention, the light-emitting device comprises a radiation source that emits in the range of ≥ 400 nm to ≤ 500 nm, and the phosphor ceramic is excited by the radiation source. The radiation source is preferably selected from the group of semiconductor LEDs, laser diodes, solid-state lasers, dye lasers, or excimer lasers.

[0045] This has proven to be particularly advantageous as it allows a high radiation density to be achieved, especially compared to currently used systems.

[0046] According to a preferred embodiment of the invention, the light-emitting device comprises a second radiation source that emits in a different range than the first radiation source, i.e., approximately at 635 nm, wherein the phosphor ceramic is also excited by the second radiation source. The radiation source is preferably selected from semiconductor LEDs, laser diodes, solid-state lasers, or excimer lasers.

[0047] The aforementioned components to be used according to the invention as well as those claimed and described in the exemplary embodiments are not subject to any special exceptional conditions in terms of their size, shape, material selection and technical conception, so that the selection criteria known in the field of application can be applied without restriction.

[0048] Further details, features, and advantages of the subject matter of the invention will become apparent from the dependent claims and the following description of the accompanying drawings, in which several exemplary embodiments of the device according to the invention are shown, as well as from the following examples, which are purely illustrative and not to be considered restrictive. In the drawings: Fig. 1 an emission spectrum of a ceramic according to a first embodiment of the invention Fig. 2 an emission spectrum of a ceramic according to a second embodiment of the invention Fig. 3 an emission spectrum of a ceramic according to a third embodiment of the invention Fig. 4 an emission spectrum of a ceramic according to a fourth embodiment of the invention Examples

[0049] The following examples are all illustrative and not limiting. Synthesis of the microscale phosphor componentsa) Synthesis of GdAl3(BO3)4:Cr 3+ (1%)

[0050] 1.8125 g (5 mmol) of Gd2O3, 1.5141 g (14.85 mmol) of Al2O3, 2.4733 g (40 mmol) of H3BO3, and 0.1200 g (0.3 mmol) of Cr(NO3)3 9H2O are ground with acetone in an agate mortar. The dried powder is transferred to a corundum crucible and calcined in air at 500 °C for 2 h. The resulting powder is ground again and heated in air at 1100 °C for 4 h. 4.7418 g (10 mmol) of GdAl3(BO3)4:Cr are obtained. 3+ (1%) received. b) Synthesis of YAl3(BO3)4:Cr 3+

[0051] 1.1290 g (5 mmol) of Y2O3, 1.5141 g (14.85 mmol) of Al2O3, 2.4733 g (40 mmol) of H3BO3, and 0.1200 g (0.3 mmol) of Cr(NO3)3 9H2O are ground with acetone in an agate mortar. The dried powder is transferred to a corundum crucible and calcined in air at 500 °C for 2 h. The resulting powder is ground again and heated in air at 1100 °C for 4 h. 4.0583 g (10 mmol) of YAl3(BO3)4:Cr are obtained. 3+ (1%) received. c) Synthesis of CaCuSi4O 10

[0052] 0.6355 g (10 mmol) of Cu (copper powder), 1.0009 g (10 mmol) of CaCO3, 2.4032 g (40 mmol) of SiO2, and 0.2 g of NaCl as a flux are ground with acetone in an agate mortar. The dried powder is transferred to a porcelain crucible and calcined in air at 850 °C for 12 h. The resulting powder is stirred in hot HCl (32%) for 10 min, filtered, and washed with H2O in a suction filter until pH 7 is reached. The washed product is dried in air at room temperature. d) Synthesis of Na3RbMg7(PO4)6:Eu 2+ (1%)

[0053] 0.7949 g (7.5 mmol) of Na2CO3, 0.5774 g (2.5 mmol) of Rb2CO3, 3.0494 g (7 mmol) of Mg5(CO3)4(OH2)·H2O, and 3.9617 g (30 mmol) of (NH4)2HPO4 are ground with acetone in an agate mortar. The dried powder is transferred to a corundum crucible and calcined in air at 800 °C for 2 h. The resulting powder is ground in a mortar and heated in forming gas (H2 / N2 5 / 95) at 1100 °C for 6 h. Production of composite ceramicsa) 2-component ceramics

[0054] 12 mg Y3Al5O 12 :Ce 3+ and 12 mg CaCuSi4O 10 are ground in an agate mortar. A drop of amyl alcohol is added, and the resulting mixture is pressed in a uniaxial press with a punch diameter of 8 mm for 5 minutes at a pressure of 3 t (equivalent to 0.23 GPa). A compact approximately 0.3 mm high is produced. This green body is heated in air at 850 °C for 6 hours.

[0055] The Fig. 1 and Fig. 2 show emission spectra of a 2-component ceramic made of Y3Al5O 12 :Ce 3+ and CaCuSi4O 10 in the ratio 1:1 [w / w, this also applies in the following] ( Fig. 1) and 7:3 ( Fig. 2) at 450 excitation.

[0056] One can clearly see that, among other things, due to the excitation of CaCuSi4O 10 in the emission range of Y3Al5O 12 :Ce 3+ , a good adjustment of the emission of the ceramic is possible. b) 2-component ceramic

[0057] 150 mg Gd3Sc2Al3O 12 :Ce,Cr and 150 mg (Ca 0,25 Sr 0,75 )CuSi4O 10are homogeneously ground in an agate mortar with three drops of amyl alcohol. A sample of 35-40 mg is taken and filled into a press tool (d = 8 mm). The compact is produced in a uniaxial press (t = 5 min) with 3 t (corresponding to 0.23 GPa). It is then sintered for 6 h at 950 °C.

[0058] Fig. 3 shows an emission spectrum of a 2-component ceramic, which analogously to example b) is made of Gd3Sc2Al3O 12 :Ce,Cr(50%) and CaCuSi4O 10 (50%), with three emission bands at 450 nm excitation. The ceramic exhibits broadband emission over a wide spectral range c) 3-component ceramic

[0059] 12 mg Y3Al5O 12 :Ce 3+ , 12 mg YAl3(BO3)4:Cr 3+ and 12 mg CaCuSi4O 10are ground in an agate mortar. A drop of amyl alcohol is added, and the resulting mixture is pressed in a uniaxial press with a punch diameter of 8 mm for 5 minutes at a pressure of 3 t (equivalent to 0.23 GPa). A compact approximately 0.3 mm high is produced. This green body is heated in air at 850 °C for 6 hours. d) 3-component ceramic

[0060] 45 mg Gd3Sc2Al3O 12 :Ce,Cr, 204 mg SrSc2O4:Eu and 51 mg (Ca 0,25 Sr 0,75 )CuSi4O 10 are homogeneously ground in an agate mortar with three drops of amyl alcohol. A sample of 35-40 mg is taken and filled into a press tool (d = 8 mm). The compact is produced in a uniaxial press (t = 5 min.) with 3 t (corresponding to 0.23 GPa). It is then sintered for 6 hours at 950°C between corundum plates under an N2 atmosphere.

[0061] Fig.4 shows the emission spectrum of a ceramic consisting of Gd3Sc2Al3O 12 :Ce,Cr(15%), SrSc2O4:Eu(68%) and (Ca,Sr)CuSi4O 10 (17%) at 450 nm excitation. The ceramic exhibits broadband emission over a broad spectral range. e) 4-component ceramic

[0062] 10 mg Na3RbMg7(PO4)6:Eu, 10 mg Y3Al5O 12 :Ce 3+ , 10 mg Ca3Sc2Si3O 12 :Cr 3+ and 10 mg CaCuSi4O 10 are ground in an agate mortar. A drop of amyl alcohol is added, and the resulting mixture is pressed in a uniaxial press with a punch diameter of 8 mm for 5 minutes at a pressure of 3 t (equivalent to 0.23 GPa). A compact approximately 0.3 mm high is produced. This green body is heated in air at 850 °C for 6 hours.

[0063] The individual combinations of components and features of the previously mentioned embodiments are exemplary; the exchange and substitution of these teachings with other teachings contained in this document and the cited documents is also expressly contemplated. Those skilled in the art will recognize that variations, modifications, and other embodiments described herein may also occur without departing from the spirit of the invention.

[0064] The word "comprising" as used in the claims does not exclude other components or steps. The indefinite article "a" does not exclude the meaning of a plural. The mere fact that certain measures are recited in mutually different claims does not clarify that a combination of those measures cannot be used to advantage.

Claims

[1] Fluorescent ceramic comprising a first component which emits in the range from ≥ 500 to ≤ 650 nm and a second component which absorbs in the range from ≥ 500 to ≤ 650 nm and emits in the range from ≥ 900 to ≤ 1000 nm; wherein the first component is a material selected from the group consisting of (M I 1-x-y M II x M III y )3(M IV 1-z M V z )5O 12 with M I = Y, Lu, Tb; M II = Gd, Yb; M III = Ce, Pr, Yb; M IV = Al; M V = Ga, Sc and 0.0 ≤ x ≤ 1.0; 0.0 ≤ y ≤ 0.1; 0.0 ≤ z ≤ 1.0 or (La 1-x Y x )3Si6N 11 :Ce, ß-SiAlON:Eu, (Ca 1-x Sr x )Sc2O4:Ce, La(Ba 1-x Sr x )2AlO5:Ce 3+ (Ba 1-x Sr x )(Y 1-x Lu x )2Al4SiO 12 :Ce 3+ , (Ba 1-x Si x )2SiO4:Eu 2+, Li2BaSiO4:Eu 2+ , RbLi(Li3SiO4)2:Eu 2+ , (Ba 1-x-y ,Sr x Ca y )Si2O2N2:Eu 2+ , Ca7(PO4)2(SiO4)2:Eu 2+ , Ca2BO3Cl:Eu 2+ , Ba2LiSi7N 11 :Eu 2+ , (Ba 1-x-y Sr x Ca y )LnSi4N7:Eu 2+ (Ln = Y, La, Gd, Lu), Ca2Al3O6F:Eu 2+ , Ba2LiSi7AlN 12 :Eu 2+ or Ca3Si2O4N2:Eu 2+ with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof; and wherein the second component is a material selected from the group consisting of Mg2SiO4:Cr, (Y 1-x-y Gd x Lu y )Al3(BO3)4:Cr, (Y 1-x-y-z La x Gd y Lu z )3(Al 1- a Ga a )5O 12 :Cr, (Ca 1-x Sr x )Sc2O4:Cr, Ca3(Sc 1-x Ga x )2Si3O 12 :Cr, La3Ga5GeO 14 :Cr, (Y 1-x- y Gd x La y )AlO3:Cr, (Ca 1-x- ySr y Bay )CuSi4O 10 or (Ca 1-x-y Sr y Ba y )CuGe4O 10 , La2MgZrO6:Cr 3+ , Mg3Ga2GeO8:Cr 3+ , BaZrSi3O9:Cr 3+ , K2Ga2Sn6O 16 :Cr 3+ , Mg 14 Ge5O 24 :Cr 3+ ,Cr 4+ , LiScP2O7:Cr 3+ , Ca2LuZr2Al3O 12 :Cr 3+ , K3LuSi2O7:Eu 2+ , LaMgGa 11 O 19 :Cr 3+ , Ca2LuScGa2Ge2O 12 :Cr 3+ , Ba3(PO4)2:Mn 5+ , LiInSiO4:Cr 3+ , ScBO3:Cr 3+ or MgAl2O4:Mn 2+ with x, y, z, a = 0.0 - 1.0 and mixtures thereof. [2] The phosphor ceramic according to claim 1, having a density of ≥ 90% to ≤ 100% of the theoretical density. [3] A phosphor ceramic according to any one of claims 1 and 2, comprising a third component which emits in the range of ≥ 650 to ≤ 900 nm. [4] Leuchtstoffkeramik gemäß Anspruch 3, wobei die dritte Komponente ein Material ausgewählt aus der Gruppe enthaltend aus (Ca 1-x Mr. x )Sc2O4:Eu, (Ca 1-x Mr. x )O:I, (Ca 1-x Mr. x )AlSiN3:Eu, (Ca 1-x-y Mr. x Ba y )2Si5N8:Eu, (Ca 1-x-y Mr. x Ba y )2Si 5-y Al y N 8-y THE y :I, (Ba 1-x Mr. x )3ScB3O9:Eu 2+ , K3ScSi2O7:Eu 2+ , (Ba 1-x-y Mr. x Here y )LiAl3N4:Eu 2+ , (Mr. 1-x Here x )4(PO4)2O:I 2+ , Rb3YSi2O7:Eu 2+ , (Mr. x Here 1-x )SiO4:Eu 2+ , (Ba 1-x Here x )4Si6ON 10 :I 2+ , (Ba 1-x Mr. x )4LiAl 11 N 14 :I 2+ , Rb3YSi2O7:Eu 2+ , (Y 1-x Lu x )4(Ba 1-x Mr. x )2Si9N 16 O2: Me 2+, Sr2BeAl3N5:Eu 2+ , Li2(Sr 1-x Ca x )2Mg2Si2N6:Eu 2+ , BaCa2Y6O 12 :Ce 3+ or Sr3Sc4O9:Ce 3+ with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof [5] The phosphor ceramic according to any one of claims 1 to 3, comprising a fourth component which emits in the range of ≥ 420 to ≤ 500 nm [6] The phosphor ceramic according to claim 5, wherein the fourth component is a material selected from the group consisting of Na3(Rb 1-x Cs x )Mg7(PO4)6:Eu, Sr6BPsO 20 :Eu, BaAl2Si2O8:Eu, (Ca 1-x Sr x )Al2O4:Eu, (Ca 1-x Sr x )2MgSi2O7:Eu, (Ca 1-x Sr x )3MgSi2O8:Eu, Ba5SiO4Br6:Eu, (Ba 1-x Sr x )MgAl 10 O 17 :Eu, (Y 1-x Gd x )2SiO5:Ce, (Y 1-x Gd x )BO3:Ce, (Sr 1-x Ba x )5(PO4)3Cl:Eu, (Na 1-x Li x )SrPO4:Eu 2+, Sr2P2O7:Eu 2+ , Sr2ZnSi2O7:Eu 2+ , K2Al2B2O7:Eu 2+ , RbNa3(Li3SiO4)4:Eu 2+ , (Ba 1-x Sr x )Li2Be4O6:Eu 2+ , SrB2O4:Eu 2+ , KBaYSi2O7:Eu 2+ , BaAl2Si2O8:Eu 2+ , (Ba 1-x-y Sr x Ca y )8Mg7Si9N 22 :Eu 2+ , Sr3Al 10 SiO 20 :Eu 2+ , SrMg2Al 16 O 27 :Eu 2+ or Na(Ba 1-x Sr x )BO3:Ce 3+ with x = 0.0 - 1.0 and y = 0.0 - 1.0 and mixtures thereof [7] A light-emitting device comprising a phosphor ceramic according to any one of claims 1 to 6, comprising a radiation source which emits in the range of ≥400 nm to ≤500 nm and wherein the phosphor ceramic is excited by the radiation source. [8] A light-emitting device according to claim 7, comprising a second radiation source which emits in a different region than the first radiation source, wherein the phosphor ceramic is also excited by the second radiation source.

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