Note: Descriptions are shown in the official language in which they were submitted.
llZ5494
The present invention relates to a phosphor which is
excited by infrared rays and has an emission spectrum in
the infrared ray region.
A phosphor activated with neodymium ions ~Nd3+), for
example, LiNdP4012, is conventionally used in optical
card readers. In such readers, a card on which informa-
tion has been recorded by a phosphor is exposed to the
rays of an excitation light source having an emission
spectrum corresponding with the excitation wavelength of
the phosphor, and by detecting selectively the emission
from the phosphor, the information recorded in the card
can be precisely read.
However, the emission intensity of the conventional
neodymium-activated phosphor is not completely satis-
factory for card readers.
One of the inventors of the present invention has
already proposed a phosphor having a emission intensity
higher than that of the conventional neodymium-activated
phosphor, for example a phosphor having a composition of
NaNdxYbyP40l~ tsee U.S. Patent 4,10..7,.~73 iss.ue.d
August 15, 1978~.
The following references are cited to show the state ~ .
of the art:
U.S. Patent No. 3,473,027
Japanese Patent Application Laid-Open Specification
No. 60888/78
It is a pri~ary object of the present invention to
provide a phosphor having a high emission intensity.
In accordance with the present invention, this and
other objects can be attained by a phosphor co-activated
with Nd and Yb, which is represented by the following
- 2 -
.~
l~Z5494
general formula:
Lnl-x-yNdxybyz
wherein: Ln stands for at least one element selected
from the group consisting of Bi, Ce, Ga, Gd, In, La, Lu,
Sb, Sc and Y; Z stands for a composition represented by
A5(Mo4)4 in which A stands for at least one element
selected from the group consisting of K and Na and M
stands for at least one element selected from the group
consisting of W and Mo, D3(BO3)4 in which D stands
for at least one element selected from the group consisting
of ~ and Cr~ PsO14, A3(PO4)2 in which A is as defined
above~ Na2Mg2(vo4)3 or A'(MO4)2 in which A' stands for
at least one element selected from the group consisting of
Li, Na and K and M is as defined above; x is a value in
the range of 0.01 < x < 0.99; ar.d y is a value in the
range of 0.01 ~ y ~ 0.99 with the proviso that the sum
of x and y is in the range of x + y ' 1.
- Preferred forms of the invention will be described in
detail in the following with reference to the accompanying
drawings, in which:-
Fig. 1 is a view illustrating the relative responsivity
spectrum of an example of a silicon photo-detector;
~!: Figs. 2, 4, 5, 8, 9, 13, 15 and 17 are views illus-
trating the relation between the composition and the
relative emission intenslty in embodiments of the phosphor
of the present invention; and
., .
-, Figs. 3, 6, 7, 10, 11, 12, 14, 16 and 18 are views
- showing the- emission spectra of embodiments of the
phosphor of the present invention.
The phosphor o~ the present invention is an oxysalt
phosphor in the broad sense, which is characterized in
-- 3 --
-
" ~:
1125494
that it contains ytterbium ions (Yb3+) and neodymium
ions (Nd3+) as the activator. The phosphor has a high
quantum efficiency of emission and has a large absorption
cross section by neodymium ions in the infrared ray
region. Further, in the phosphor of the present
invention, energy is transferred at high efficiency from
excited neodymium ions to ytterbium ions, and emission in
the vicinity of 980 nm is thereby caused in the ytterbium
ions. Accordingly, the phosphor of the present invention
has an emission spectrum which corresponds closely with
the wavelength region of the silicon photo-detector used
most commonly in the near infrared wavelegth region (for
example, an Si-PIN photo-detector). The relative respon-
sivity spectrum of such a silicon photo-detector is shown
in Fig. 1.
The conventional neodymium-activated phosphor mainly
has an emission in the vicinity of 1050 nm and an emission
in the vicinity of 900 nm. The emission in the vicinity
of 900 nm overlaps greatly with the emission from an
,~ ~
~20 excitation light source. Accordingly, only the emission
in the vicinity of 1050 nm is detected by using an
~:
u~ appropriate filter in the conventional neodymium-activated
phosphor.
The phosphor of the present invention has an emission
in the vicinity of 980 nm, as pointed out hereinbefore, if
the ytterbium ion concentration, namely the value of y in
~; the above general formula, is in the range of from 0.01 to
0.99. Even if the value of y is as small as 0.01, the
emission intensity is drastically increased over the
emission intensity of the ytterbium-free phosphor.
Further, even if an ion capable of being trivalent and
~ 5494
having no absorption in the wavelength region of 800 to
1000 nm, namely at least one ion selected from the group
consisting of Bi, Ce, Ga, Gd, In, La, Lu, Sb, Sc and Y, is
co-present with neodymium and ytterbium, the phosphor of
the present invention has effects which are superior to
those attainable from the conventional phosphor activated
only with neodymium ions.
Furthermore, in the phosphor of the present invention,
a high emission intensity can be obtained not only when it
is excited by infrared rays but also when the energy level
of the neodymium ion in the visible or ultraviolet ray
region is excited by an argon laser or the like.
The present invention, and particularly preferred
forms thereof, will now be described in more detail.
A first group of the phosphors of the present
invention is characterized by the fact Z in the general
formula stands for a composition A5(MO4)4. Thus,
; this group of phosphors can be represented by the
following general formula:
Lnl-x-yNdxybyAs(Mo4~4
These phosphors can be obtained by weighing the
:- .
starting materials, namely A2CO3, Ln203 (which may be CeO2
when Ln is Ce), Nd2O3, Yb2O3 and WO3 and/or MoO3, so
that the intended composition will be attained, mixing
them sufficiently, preferably pelletizing the mixture, and
sintering the mixture at a temperature of 600 to 650C for
1 to 2 days in a platinum or quartz crucible.
Fig. 2 illustrates the relationship between the
composition of the phosphor and the relative emission
intensity (calculated based on the assumption that the
intensity of the composition in which y is 0 ;s 1) of
- . '
llZS494
I
5Ndl-yYby(wo4)4 and NasNdl_yYby(M004)4~
For excitation of the phosphors, a (Ga,~Q)As light
emitting diode having a peak at 800 nm was used, and the
emission intensity was measured by a photo-multiplier
having a photo-cathode of the S-l type.
The phosphor of the present invention shows emission
at a characteristic wavelength when the values of x and y
are in the above-mentioned ranges. From Fig. 2, it can be
seen that the values of x and y providing a preferred
phosphor of the first group having a higher emission
intensity are in the following ranges:
0.25 ' x ' 0.99 and 0.01 ' y ' 0.75.
It is most preferred that x and y be in the following
ranges:
0.65 ' x ' 0.95 and 0.05 ' y ' 0.35.
A phosphor belonging to the second group of the ~ -
present invention is one in which Z stands for a
composition represented by D3(B03)4, namely a phos-
phor represented by the following general formula:
Lnl_x_yNdxybyD3(Bo3)4
This phosphor can be obtained by weighing the starting
materials, namely D203, D(OH)3 or D2(S04)3, Ln203
(which may be CeO2 when Ln is Ce), Nd203, Yb203 and
B203, so that a stoichiometric composition correspond-
ing to the intended composition is attained; however, the
amount of B203 may be up to 1.5 times in excess over
the stoichiometric amount. The starting materials are
mixed sufficiently, pelletized and the pellets sintered at
about 1100C for 3 days in a platinum or quartz crucible.
Fig. 4 illustrates the relationship between the
composition of the phosphor and the relative emission
-- 6 --
llZSq~94
I
intensity (calculated based on the assumption that the
intensity of the composition in which y is 0 is 1) in
phosphors of A~3Ndl_yYby(BO3)4. The measurement was
conducted in the same manner as described above with
respect to Fig. 2. The phosphor of the present invention
shows an emission of a characteristic wavelegth when the
values of x and y are in the above-mentioned ranges. From
Fig. 4, it can be seen that the values of x and y pro-
- viding a preferred phosphor of the second group having a
high emission intensity are in the following ranges:
0.10 < x _ 0.99 and 0.01 _ y _ 0.90.
It is most preferred that x and y be in the following
ranges:
0.60 ' x ' 0.98 and 0.02 ' y ' 0.40.
Fig. 5 illustrates the relationship between the Cr
concentrations (z) and the relative emission intensity
(calculated based on the assumption that the intensity
of NdAQ3(BO3)4 is 1) in phosphors of
0.9Ybo.l(AQl-zcrz)3(Bo3)4. From Fig. 5,, ~ 20 it can be seen that the higher the A concentration, the
higher the emission intensity.
~; A phosphor belonging to the third group of the present
invention is one in which Z stands for a composition
represented by P5014, namely a phosphor represented by
the following general formula:
Lnl_x_yNdxybyp5ol4
This phosphor can be obtained by weighing the starting
materials, namely Ln203 (which may be CeO2 when Ln
is Ce), Nd23~ Yb23 and NH4H2PO3 so that the amount
of P205 is at least 3 times in excess over the
stoichiometric amount and the amounts of other components
are stoichiometric amounts corresponding to the intended
- 1125494
composition, mixing them sufficiently and sintering
themixture in a lidded gold crucible at 500 to 800C. for
about 1 to about 5 days.
Fig. 8 illustrates the relationship between the com-
position of the phospXor and the relative emission
intensity (calculated based on the assumption that the
intensity of the composition in which y is 0 is 1) in
phosphors of Ndl_yYbyP5014, and Fig. 9 illustrates
the relationship between the composition of the phosphor
and the relative emission intensity of phosphors of
LnO.9-XNdXYbO.lPsO14 in which Ln is Bi, Gd or Y.
The measurement was carried out in the same manner as
described above with respect to Fig. 2.
From these Figs., it can be seen that values of x and
y providing a preferred phosphor of the third group having
a high emission intensity are in the following ranges:
0.05 _ x _ 0.98 and 0.02 < y < 0.95.
It is most preferred that x and y be in the following
ranges:
0.18 ~ x ' 0.95 and 0.05 ' y ' 0.82.
A phosphor belonging to the fourth group of the phos-
phor of the present invention is one in which Z stands for
a composition represented by A3(PO4)2, namely a
phosphor represented by the following general formula:
~nl_x_yNdxybyA3(po4)2
This phosphor can be obtained by weighing starting
materials, namely A2CO3, Ln203 ~which may be CeO2 when Ln
is Ce), Nd23~ Yb203 and NH4H2PO4, so that the intended
composition can be attained, mixing them sufficiently and
sintering the mixture in a lidded platinum crucible at
about 1200C for about 20 hours.
Fig. 13 illustrates the relationship between the
-- 8 --
1~2Sg~94
I
composition of the phosphor and the relative emission
intensity (calculated based on the assumption that the
intensity of the composition in which y is O is 1) in
phosphors of K3Ndl_yYby(P04)2. The measurement
was carried out in the same manner as described above with
respect to Fig. 2.
As can be seen from Fig. 13, values of x and y
providing a preferred phosphor of this group having
a high emission intensity are in the following ranges:
0.02 ' x ''0.98 and 0.02 < y c 0.98.
It is most preferred that x and y be in the following
ranges:
0.09 ' x ' 0.98 and 0.02 ' y ' 0.91.
A phosphor belonging to the fifth group of the present
invention is one in which Z stands for a composition
represented by Na2Mg2~V04)3, namely a phosphor rep-
resented by the following general formula:
-:~
~ Lnl_x yNdxybyNa2Mg2~vo4)3
;~ This phosphor can be obtained by weighing Na2C03,
MgO, Ln203 (which may be CeO2 when Ln is Ce),
Nd203, Yb203 and NH4V03 so that the intended composition
can be attained, mixing them sufficiently, pelletizing the
mixture and sintering the pellets in a quartz, alumina or
platinum crucible at about 800C for about 30 hours.
Fig. 15 illustrates the relationship between the
composition of the phosphor and the relative emission
intensity (calculated based on the assumption that the
intensity of the composition in which y is O is 1) in
phosphors of Ndl_yYbyNa2Mg2(V04)3. The measurement was
carried out in the same manner as described above with
respect to Fig. 2.
_ g _
. . .
l~Z5~g4
From Fig. 15, it can be seen that values of x and y
providing a preferred phosphor of the fifth group having a
high emission intensity are in the following ranges:
0.57 < x < 0.90 and 0.10 < y < 0.53.
A phosphor belonging to the sixth group of the phosphor
of the present invention is one in which Z stands for a
composition represented by A'(MO4)2, namely a phosphor
represented by the following general formula:
Lnl-x-yNdxybyA (M4)2
This phosphor can be obtained by weighing A'2CO3,
Ln203 (which may be CeO2 when Ln is Ce), Nd203,
Yb203 and MO3 so that the intended composition can be
attained, mixing them sufficiently, pelletizing the
mixture and sintering the pellets in a quartz or alumina
crucible at about 700C for about 3 days.
- Fig. 17 illustrates relationship between the
composition of the phosphor and the relative emission
intensity (calculated based on the assumption that the
intensity of the composition in which y is 0 is 1) in
phosphors of LiNdl_yYby(WO4)2 and LiNdl_yYby~MO04)2.
The measurement was carried out in the same manner as
described above with respect to Fig. 2.
From Fig. 17, it can be seen that values of x and y
providing a preferred phosphor of the sixth group having a
high emission intensity are in the following ranges:
0.20 = x = 0.95 and 0.05 = y = 0.80
The phosphor of the present invention will now be
described in detail by reference to the following Examples.
Example 1
A powdery starting material comprising 0.5 mole of
Na2CO3, 0.-08 mole of Nd203, 0.02 mole of Yb203 and 0.8
` -- 10 --
llZ5~94
mole of WO3 was sufficiently blended and pulverized, and
was then pelletized and charged to a quartz crucible. The
crucible was placed in an electric furnace and the tem-
perature was elevated to 650C at a rate of about
150C/hr, and the pellets were sintered at 650C for 50
hours. After completion of the sintering, the product was
cooled and mechanically crushed to obtain a powdery
p p or of NdO.8YbO.2Na5(WO4)4 having a particle size (as
determined by a Bleine air permeability apparatus; each of
the particle sizes mentioned hereinafter is one determined
by this apparatus) of about 5 ~m. The emission spectrum
of the so obtained phosphor is indicated by a dot line in
Fig. 3. The relative emission intensity of this phosphor
was 115 (calculated based on the assumption that the
intensity of LiNdo gYbo lP4012 is 100; the same holds good
hereinafter, unless otherwise indicated).
A phosphor of Ndo 8Ybo.2K5tWO4)4 was prepared
by conducting treatments in the same manner as decribed
above except that K2C~3 was used instead of Na2CO3
in the powdery starting material. The emission spectrum
of this phosphor was substantially the same as the
spectrum indicated by a dot line in Fig. 3.
~,
A powdery starting material comprising 0.5 mole of
Na2CO3, 0.09 mole of Nd203, 0.01 mole of Yb203 and 0.8
mole of MoQ3 was sufficiently blended and pulverized,
and was then treated in the same manner as in Example 1 to
obtain a phosphor of Ndo gYbo lNa5(MoO4)4. The emission
spectrum of this phosphor is indicated by a solid line in
Fig. 3. Namely, the emission spectrum of this phosphor
was substantially the same as that of the phosphor of
-- 11 --
llZ5494
Example 1. The relative emission intensity of this phos-
phor was 107.
A phosphor of Ndo gYbo lK5(~ioOL~)4 ~as prepared by
conducting treatrnents in the same manner as described
above except that K2C03 ~as used instead of Na2CO~ in
the powdery starting material. The emission spectrum of
-this phos~hor was substantially the same as that o~ the
phosphor of Example 1.
Exam~le 3
A po~rdering starting material comprising 0.5 mole of
Na2C03, 0.01 mole of Y203, 0.075 mole of Nd203, 0.015 mole
of Yb203 and 0.8 mole of '.~03 was sufficiently blended and
~ pulverized, and was then treated in the same manner as
;; in Example 1 to ob-tain a phosphor ol YO lNdo 75Ybo ~W04)4
The emission spec-trum of this phosphor was substantially
the same as that of the phosphor OI Example 1, and the
~' relative emission intensity was 104.
Phosphors were prepared in the same manner by using
2 3~ Ce2- Ga203~ Gd203, In203, La203~ LU23' Sb23 or
20 ~ Sc203 ( 0.02 mole in case of CeO2 ) instead of Y203.
The emission spectrum was substantiàlly the same in these
phosphors.
Also in the case rhere K2CO~ was used instead of
Na2C03, the emission spec-trum ~as substantially the same
as above.
Exam~le L~
po~ldery starting material comprising 0.5 mole of
~la2C03, 0.08 mole of Nd203, 0.02 mole of Yb203, 0 4 mole
of ;l03 and 0.4 mole of MoO~ was sufficiently blended
and pulverized, and was then treated in the same manner
5494
I
as in Example 1 to obtain a phosphor of Ndo ~Ybo 2Na5-
(I~ioO 51:10 5OL)~. The emission spectrum of the phosphor was
substantially the same as that of the phosphor of Example 1
and the relative emission intensity was 110.
Example 5
A powdery startin~ material comprising 0,5 mole of
Na2C03, 0.01 mole of CeO2, 0~005 mole of Gd203, 0.075
mole of Nd203, 0.015 mole of Yb203, 0.56 mole of :J03
~; and 0.24 mole of MoO3 was sufficiently blended and pulveri-
zed, and then treated in the same manner as in Example 1
:
to obtain a phosphor of~CeO 05Gdo.05Ndo.75Ybo.15N 5( 0.7
MoO 304)4. The emission spectrum of this phosphor~was
substantially the same as that of the phosphor of Example
1 and the relative emission intensity was 101. ~;
Example 6
A powdery starting material comprising 0.5 mole of
K2C03, 0.01 mole of Bi203, 0.075 mole of ~d20~, 0.015 mole
o~ Yb203 and 0.8 mole of MoO3 was sufficiently blended
and pulverized, and was then treated in the same ma~ner~ ;
, ~ ~
as in Example 1 to obtain a phosphor of Bio lNdo 75Ybo 15
K5(I~IoO4)4. The emission spectrum o~ -this phosphor ~as
substantially the same as that o~ the phosphor of Example
1 and the relative emission intensity was 97.
Examp3e 7
A powdery startin~ material comprisin~ 0.05 mole of
K~C03, 0.45 mole of i~a2C03, 0.01 mole of La203, 0.08 mole
of Nd203, 0,0] mole of Yb20~ and 0.8 mole of W03 was
sufficiently blended and pulverized, and was then treated
in the same manner as in Example 1 to obtain a phosphor
O.lr~dO.8Y~o.l(Nao.~o.l)s(wol~)L~. The emission
spectrum of this phosp~or was substantially the same as
- 13 -
1125494
tnat of the phosphor of ~xample 1 and the relative emission
intensity /as 103,
l~;Y~am~le ~3
A powdery starting material comprising 0.3 mole of
A~0~, 0,09 mole of Nd2~, 0,01 mole of Yb203 and 0,4
mole of B203 ~ras sufficiently blen~ed and pulverized, and
was then pelle-tized and charged to a quartz crucible.
The crucible was placed in an elec-tric furnace and the
temperature ~Jas elevated to 1100C, at a rate of about
100C,/hr. The pellets ~ere sintered at 1100C, for 80
hours. After completion of the sintering, the produc-t
was cooled and mechanically crushed to obtain a po~dery
!: ~
p p f i~0,9Ybo,lA~3(B03)4 having a particle size of
about 5 ~m, The emission spectrum of the so obtained
phosphor is sho~rn in Fig. 6. The relative emission
.
intensity of t'ne phosphor was 130,
Exam~le 9
A phosphor of l~do 9Ybo lCr3(B0~)4 ~;ras prepared by
conducting treatments in the same manner as in ~xar~ple 8
2~0 ~except tha-t Cr203 was use~ instead of A~203. The emission
spectrum of the so obtained phosphor is indicated by a
s.olid line in Fig, 7. The relative emission intensity
r the phosphor was 4,
Exam~le 10
;:
A powdery starting material comprising 0.27 mole of
A~203, 0.03 mole of Cr20~, 0,09 mole of Nd203, 0,01 mole
of Yb203 and 0.4 mole of B203 was su~ficiently blended and
pulverized, and ras then treated in th~ same manner as
in ~xample ~ to obtai.n a phosphor of Ndo gYbo lA~2 7CrO 3-
(B03)4, The emission spectrum of this phosphor is indicatedby a dot line in Fig, 7. The relative emission intensity
, .
~,; ,, , , ~
llZ5494
o~ -the phosphor ~ras 57.
l:x~ l c 1 1 '
.
A po~ldery material comprising 0.~ mole of AB203, 0.01
mole of Y203, 0.0~ mole of Nd2~, 0.01 mole of Yb203 and
0.4 mole of B203 ~ras sufficiently blcllded an~ pulverized,
and was then treated in the same manner as in ~xample
to obtain a phosphor of Y0 ll~bo.~ybo~lA 3( 3)4
erilission spectrurn of the phosphor ~/as substantially the
same as that sho~m in Fig. 6.
: 10 Phosphors were prepared in the same manner as described
above by using 0.01 mole of Bi20~, Ga203, Gd203, In203,
La203, Lu203, Sb203 or Sc20~ or 0.02 rnole of CeO2 ins-tead
of Y203. Tne ernission spectrum of each of these phosphors
was substantially the same as that sho.m in Fig. 6.
The emission spectrum of a phosphor prepared in the
same manner as describ:ed above by using 0.005 mole of ~ -.
,~
Bi203 and 0.005 mole of Ga203 instead of Y203 tJas sub-
s-tantially -the same as that sho~m in Fig. 6.
E~arn~le 12
A powdery starting material comprising 0.06 mole of
Nd203, 0.04 mole of Yb203 and 3.0 moles o~ NH4H2P04 was
:: sufficiently blended an~ pulveriz~d, and was ~nen pelleti~ed
and charged in a gold cruclble. The crucible was placed
in an electric furnace and the temperature was elevated to
700C, at a rate of àbout 150C./hr. The pellets were
:~. . O
sintered at 700 C. for 5 days. After completion of the
sintering, the product ~tas cooled, ~ashed sufficiently
with l"ater and mechanically crushed to obtain a pol;~dery
P P f Ndo.6Ybo.~P5l4 havin~ a particle s.ize of
about 5 ~m. Tne emiss.ion spectrum of this phosphor is
sho-,m in Fig. 10. The relative emission intensity of the
. - 15 -
`` 1125494
pho sphor was :121.
1. rn~lc 13
A powdery startin~ material comprisin~ 0.02 rnole of
Bi203, 0.06 mole of ~ld20~, 0.02 mole of Yb203 and 3.0
moles of i~THL~H2POL~ was suf`ficiently blended and pulverized,
and .~a~ then treated in the same manner as in Example 12
to obtain a pho3phor of Bio.2Ndo.GYbo.2P5014.
The emission spectrum of this phosphor ~las substantially
the same as tha-t of the phosphor of ~ample 12 and the
relative emission intensity was 105,
Each of the emission spectra of phosphors prepared
in the same manner as described above by using Ga203,
2 3' 2 3- La23, Lu203~ Sb203, Sc203 or Y203 was
substantially the same as the emission spectrum of the
phosphor of EY~ample 12.
~:: Example 14
A powdery starting material comprising 0.04 mole of
, :
CeO2, 0.05 mole of Nd203, 0.03 mole of Yb203 and 3.0 moles
of NH4H2P04 was sufflciently blended and pulverized and
was then treated in the same manner as in Example 12 to
obtain a phosphor of CeO 2Ndo 5Ybo 3P5014,
The emission spectrum of this phosphor is sho~m in
Fig, 11. The relative emission intenxity of the phosphor
:
: wa3 10~,
Exam~le 15
A powdery starting material comprising 0.01 mole o~
Gd203, 0.02 mole of Y203, 0.05 mole of l~d20~, 0.02 mole
of Yb20~ and 3,0 moles of NH4H2P04 was sufficiently blended
and pulverized, and was then treated in the same manner as
in Example 1~ to obtain a phosphor of Gdo lYo 2?ldo 5Ybo 2~5-
14-
,
- 16 -
1125494
. .
The emission spectrurn of this phosphor i~ sho~ in
Eig. 12. The relative ~mission intensity of the phosphor
was 97.
~xam~le 16 -
. . . - ~
A po.ldery starting material compri sing O . 3 mole of
K2C0~, 0.0~ mole of Nd203, 0.02 mole of Yb203 and 0.4
mole of NII4H2POl~ was sufficiently blended and pulverized,
and was then pelletized and charged in a platinum crucible.
The crucible was placed in an eIectric furnace and the
temperature was elevated to 1200C. at a rate of about
200C./hr. The pellets were sintered at 1200C. for 20
hours. After completion of the sintering, the product
- was cooled and mechanicaIly crushed to obtain a powdery
P phor of Ndo.8YbO 2K3(P04)2 having a particle size of
about~S ~m. The~emlsslon spectru.~ of this phosphor is
sho~ in Fig. 14.~ me relative emission in-tensity of the
phosphor ~las 87.
Examples 17 to 19
Pho3phors~ of ~YO lMdO~,gYbO.11~3~P0432~ CeO.05YO.05 0.8
20~ Ybo lK~3(PO~z :and~ GdO O5yo.o5Ndo.8ybo.l(Ko.gNao~l)3(po4)2
rere~prepared by suf~iclently blendin~ and pulverizing ` .:
po~,~rdery starting materials sho~n in the follo~rin~ Table ~`
anl treatin~ them in -the same manner as in Example 16.
: ''' ~ ' '
~ 30
: :
;. -
- 17 -
11;:54~4
Table
~xam~le 1'~ Example 1~ am~le 19
Na2C03 - - 0.03 mole
K2C03 0 3 mole 0.3 mole 0.27 mole
203 0.01 mole 0.005 mole 0.005 mole
CeO2 - 0.01 mole
Gd203 - _ 0.005 mole
Nd 03 0,08 mole 0,08 mole 0.0~ mole
2 3 0,01 mole 0.01 mole 0.01 mole
10 NH4H2P04 0.4 mole 0.4 mole 0.4 mole
The emission spectra of these phosphors were substan-
tially the same as that sho~m in Fig. 14. The rela-tive
emission intensities of these phosphors were 85, 85 and
79, respectively.
.
Emission spectra of phosphors prepared in the same
manner as described above by using Bi203, Ga203, In203,
é~ La2~, Lu203~ ~Sb20~3 or Sc203 instead of Y203 in Example
17 were~substantially the same as that shown in Fig. 14.
Further,~ the emlsslon spectrum of a phosphor prepared
in the same manner as described above by using Na~CO instead
of 1~2C03 in Example lrl was substantlally the ~ame as that
sho~rn in Fig. 14.
Exam~le 20
A powdery~starting material comprising 0.2 mole of
~,t~ ' Na2C03, 0.4 mole of MgO, 0.08~mole of Nd203, 0.02 mole of
Yb20~ and 0.6 mole of N~14V03 was sufficiently blended
and pulverized, and ~ras then pelletized and charg~d in a
,
quartz crucible. The crucible was placed in a~ electric
furnace and the temperature was elevated to 800C. at a
rate of about 2Q0C./hr. The pellcts were sintered at
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~300C. for 30 hours. ~fter completion of the sintering,
the product ~ras cooled and mechanically crushed -ta obtain
a po~lderY phosphor of ~do gYbo 2Na2M~2(V4)3 havin~ a '~
particle size of about 5 ~m. The emission spectrum of
this phosphor is sho~n in Fig. 18. The rela-tive emission
intensi-ty of the phosphor was 31.
E,~amples 21 a~d 22
Phosphors of La Nd 'Yb ~I M (VO ) d
,~ Lao.o5ceo.o5Ndo~75ybo.l5Na2Mg2(vo4)3 were pr~pared by
sufficiently blending a~d pulverizing po~dery starting '~
materials shown in the following Table and treating them
in -the sarne manner as in Example 20.
Table
E~ram~le 21 E~am~le 22
,~La20~ , 0.005 mole 0.005 mole
2 0.01 mole
Nd203 0.075 mole 0.075 mole
Yb203 0.02 mole 0.015 mole
. ~, .
2 3 0.2 mole 0.2 mole
; 20 ~ MgO 0.4"mole , 0.4 mole
.
'i'~N~ V03 0.6 mole 0.6 mole
: ~,
Emission,spectra of these phosphors were substantially
the same as t~lat sho-~n ln l~ig. 16, and the relative emis-
: ~ .
~ sion intensities of these phosphors ~lere 29 and 28,
,
~ respectively.
'- Emission spectra of phosphors prepared in the same
manner as described above by usin~ Bi203, Ga203, Gd203,
03, Lu203~ Sb20~, Sc20~ or Y203 in5tead of La203in
Example 21 ~Jere substantially the same as that sho~ in
Fig. 16.
.
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I
~xample 23
A powdery startin~ ma-tcrial comprising 0.1 mole of
Li2C03, 0.09 mole o~ Nd203, 0.01 mole of Yb20~ and 0.4
rnole of llO3 wa~ sufficiently blended and pulverized, and
~as then pelletized and charged in a quartz crucible.
The crucible was placed in an electric furnacc and the
temperature ~Jas elevated to 700C. at a rate of about
150C./hr. The pellets were sintere~ at 700C. for 3
days. After completion of the sintering, the product
was cooled and mechanically crushed to obtain a phosphor
of LiNdo gYbo l(W04)2 having a particle size of about 5
~m. The emission spectrum of the so obtained phosphor is
indicated by a solid line in Fig. 18. The rela-tive
emission intensity of the phosphor ~ras 71.
Emission spectra of phosphors prepared in the same
manner as described above by usin~ r~a2C03 or K2C03 instead
of Li2C03 ~ere substantially the same as that of the
; phosphor of Example 23.
ExamPles 24 to 26
Phosphora of LiNdo gYbo l(MoOL~)2, LiNdo.gYbo.l(~l0.5
MoO 50L)2 and NaO sKo~sNdo~gYbO~ 0~9 0,1 L~ 2
pr~pared by suf~iciently blending and pulverizing powdery
starting materials shown in the following Table and
~-~ treating thcm in the same manner as in Example 23.
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.,
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~,
rrable
EY~ample 24Exam~le 25Example 26
Li2~-0~0.1 mol~ 0,1 mole
Na2~03 _ _0.05 mole
K2~03 _ _0.05 mole
Nd203 0.09 mole0.09 rnole0.09 mole
; Yb20~ 0.01 mole 0.01 mole0.01 mole
~I03 ' - ~ 0.2 mole0.36 mole
ioO3 0,4 mole 0.2 mole0.04 mole `'
The emission spectrum of the phosphor of ~xample 24
is indicated by a dot Iine in F'i~. 18, which was substan-
, :~
tially the same as~the emission spectrum of the phosphor
~ of Example 23 ~rnere 11 was used, ~rhich was indicated by a
;.7~ soli.d line in Fig. 18. The relative emission lntensity ~ "
o~ the phosphor of~Example 24 was 44.~ Emission spectra ~ -
of pnosphors prep~ared~ln the same manner as in Exa~ple
,24 by~using Na2C03 or K2C03 lnstead of Li2C03 ~lere the
su~stantially the~same as that of the phosphor of Example
24~shown in Fig~. 18.
'20~ Emission speotra o~ the phosphors of Examples 2~ '~
and 26 ~/~re substantlall~J the same as that shown,in Fig.
~ la, and the relative~ emisslon intensi~ies were 53 and
.~'``'f "',~ 62, respectively. ~ ,:
mlssion sp~ectra of phosphors prepared in the same
manner as in ~xamples 23, ~4, 25 ~nd 26 by using 0.08 -;"
mo:le of Nd203 and O.Ol mole of Ga20~ instead of 0.09
mole of Nd203~ere substantially the same as tha-t sho~
in Fig. 18.
Further, emission spectra of phosphors prepared in
:, :
~ 30 the same manner as in the:foregoin~ Examples by using
' ,~;
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11'~5494
O. 01 mole of Bi203, GC120~;, In203 La23 ~ LU23 ~ Sb23 '
Sc203 or Y203 or 0.02 mole of CeO2 instead of 0.01 mole
of Ga20~ were sub stantially the same as tha-t sho~n~ in
Fi~;. 18.
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