U.S. patent application number 09/956188 was filed with the patent office on 2002-03-28 for fluorescent pattern, process for preparing the same, organic alkali developing solution for forming the same, emulsion developing solution for forming the same and back plate for plasma display using the same.
Invention is credited to Ashizawa, Toranosuke, Fujita, Eiji, Horibe, Yoshiyuki, Kimura, Naoki, Nojiri, Takeshi, Satou, Kazuya, Shimamura, Mariko, Tai, Seiji, Tanaka, Hiroyuki, Tanno, Seikichi.
Application Number | 20020037478 09/956188 |
Document ID | / |
Family ID | 27468363 |
Filed Date | 2002-03-28 |
United States Patent
Application |
20020037478 |
Kind Code |
A1 |
Kimura, Naoki ; et
al. |
March 28, 2002 |
Fluorescent pattern, process for preparing the same, organic alkali
developing solution for forming the same, emulsion developing
solution for forming the same and back plate for plasma display
using the same
Abstract
Disclosed are a phosphor pattern which comprises a calcination
product of a phosphor pattern precursor containing (A) an organic
material containing at least one selected from the group consisting
of an alkali metal and an alkaline earth metal; and (B) a phosphor
wherein an amount of the alkali metal or the alkaline earth metal
is 2% by weight or less based on the amount of (B) the phosphor, a
process for preparing the same, an organic alkali developing
solution for forming the same, an emulsion developing solution for
forming the same and a back plate for plasma display using the
same.
Inventors: |
Kimura, Naoki; (Hitachi-shi,
JP) ; Tai, Seiji; (Hitachi-shi, JP) ; Tanaka,
Hiroyuki; (Mito-shi, JP) ; Nojiri, Takeshi;
(Ibaraki-ken, JP) ; Satou, Kazuya; (Hitachi-shi,
JP) ; Horibe, Yoshiyuki; (Hitachi-shi, JP) ;
Shimamura, Mariko; (Hitachi-shi, JP) ; Ashizawa,
Toranosuke; (Hitachinaka-shi, JP) ; Fujita, Eiji;
(Hitachi-shi, JP) ; Tanno, Seikichi; (Hitachi-shi,
JP) |
Correspondence
Address: |
ANTONELLI TERRY STOUT AND KRAUS
SUITE 1800
1300 NORTH SEVENTEENTH STREET
ARLINGTON
VA
22209
|
Family ID: |
27468363 |
Appl. No.: |
09/956188 |
Filed: |
September 20, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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09956188 |
Sep 20, 2001 |
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09755153 |
Jan 8, 2001 |
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09755153 |
Jan 8, 2001 |
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09059351 |
Apr 14, 1998 |
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6232024 |
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Current U.S.
Class: |
430/321 ;
313/582; 427/64; 430/24; 430/26; 430/29; 430/331; 430/464; 430/484;
445/24 |
Current CPC
Class: |
H01J 9/2271
20130101 |
Class at
Publication: |
430/321 ; 430/24;
430/26; 430/29; 430/331; 430/464; 430/484; 313/582; 445/24;
427/64 |
International
Class: |
H01J 009/227 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 14, 1997 |
JP |
095837/1997 |
Aug 4, 1997 |
JP |
208996/1997 |
Sep 25, 1997 |
JP |
259964/1997 |
Nov 21, 1997 |
JP |
320646/1997 |
Claims
1. A phosphor pattern which comprises a calcination product of a
phosphor pattern precursor containing (A) an organic material
containing at least one selected from the group consisting of an
alkali metal and an alkaline earth metal; and (B) a phosphor
wherein an amount of the alkali metal or the alkaline earth metal
is 2% by weight or less based on the amount of (B) the
phosphor.
2. A process for preparing a phosphor pattern which comprises the
steps of preparing a phosphor pattern precursor containing (A) an
organic material containing at least one selected from the group
consisting of an alkali metal and an alkaline earth metal and (B) a
phosphor in which an amount of the alkali metal or the alkaline
earth metal is 2% by weight or less based on the amount of (B) the
phosphor, and calcining the precursor.
3. A process for preparing a phosphor pattern according to claim 1,
wherein the phosphor pattern precursor is formed by applying the
photolithography method carrying out a wet development using (C) an
alkali developer to a photosensitive resin composition containing a
phosphor.
4. A process for preparing a phosphor pattern according to claim 1,
wherein the phosphor pattern precursor is formed by applying the
photolithography method carrying out a wet development using an
emulsion developer containing water and a solvent to a
photosensitive resin composition containing a phosphor.
5. A process for preparing a phosphor pattern according to claim 1,
wherein the phosphor pattern precursor is formed by applying the
photolithography method carrying out a wet development using an
organic alkali developer to a photosensitive resin composition
containing the phosphor.
6. An organic alkali developer for forming a phosphor pattern
containing an aliphatic amine, an aromatic amine or a tetraalkyl
ammonium hydroxide.
7. An emulsion developer for forming a phosphor pattern comprising
an emulsion containing water and a solvent.
8. A back plate for a plasma display panel provided with the
phosphor pattern according to claim 1 on the substrate for the
plasma display panel.
Description
BACKGROUND OF THE INVENTION
[0001] This invention relates to a phosphor pattern, a process for
preparing the same, an organic alkali developing solution for
forming the same, an emulsion developing solution for forming the
same and a back plate for plasma display using the same.
[0002] In the prior art, as one of flat plate displays, there has
been known a plasma display panel (hereinafter referred to as
"PDP") which enables multicolor display by providing a phosphor
which emits light by plasma discharge.
[0003] In such PDP, flat front plate and back plate comprising
glass are arranged in parallel with each other and facing to each
other, both of the plates are retained at a certain interval by a
cell barrier provided therebetween, and PDP has a structure that
discharge is effected in a space surrounded with the front plate,
the back plate and the cell barrier.
[0004] In such a cell, a phosphor is coated for display, and by
discharge, the phosphor emits light by UV ray generated from filler
gas, and the light can be recognized by an observer.
[0005] In the prior art, as a method for forming the phosphor, a
method of coating a slurry liquid or a paste in which phosphors of
the respective colors are dispersed is coated by a printing method
such as screen printing has been proposed and disclosed in Japanese
Provisional Patent Publications No. 115027/1989, No. 124929/1989,
No. 124930/1989 and No. 155142/1990.
[0006] However, the above-mentioned phosphor-dispersed slurry
liquid is a liquid state so that dispersion failure is likely
caused by sedimentation of phosphors, etc. Also, when a liquid
state photosensitive resist is used as the slurry liquid, there is
a defect of markedly lowering in preservation stability with the
progress of dark reaction. Moreover, the printing method such as
screen printing is inferior in formation precision so that there
are problems that it is difficult to cope with enlargement of a
screen of PDP in the future, and others.
[0007] The method of using a liquid state photosensitive resist is
a method in which respective components constituting a
photosensitive resin composition containing phosphors are dissolved
or mixed in a solvent which is capable of dissolving or dispersing
the phosphors to prepare a liquid in which the phosphors are
uniformly dissolved or dispersed in the solvent, and the liquid is
directly coated to the above-mentioned substrate for PDP, and dried
to form a phosphor pattern.
[0008] As a method for providing phosphors, there has been proposed
a method of using a photosensitive element (it is also referred to
as "a photosensitive film") containing phosphors (Japanese
Provisional Patent Publications No. 267421/1994 and No.
273925/1994).
[0009] In the method of using a photosensitive film, a
phosphor-containing photosensitive resin layer of a photosensitive
film comprising a photosensitive resin layer containing a phosphor
and a support film is embedded in the above PDP cell by contact
bonding (lamination) under heating, the layer is subjected to
imagewise exposure with active light such as UV ray by a
photographic method using a negative film, an unexposed portion is
removed by a developing solution such as an alkaline aqueous
solution, and further unnecessary organic components are removed by
calcination to form a phosphor only at a necessary portion.
[0010] When the above-mentioned photosensitive element is used, it
is not necessary to confirm dispersibility of phosphors as
conducted in a phosphor-dispersed slurry liquid or a
phosphor-dispersed paste, and is excellent in preservation
stability as compared with the phosphor-dispersed slurry liquid or
the phosphor-dispersed paste. Moreover, since a photographic method
is used, a phosphor pattern can be formed with good precision.
[0011] However, when a phosphor pattern is formed by directly
coating a phosphor-containing liquid-state photosensitive resist to
the above-mentioned substrate for PDP, or laminating on a substrate
for the above-mentioned PDP a phosphor-containing photosensitive
resin layer using a photosensitive element, then, imagewisely
exposing with an active light such as an ultraviolet ray, etc.,
according to the photographic method, thereafter removing an
unexposed portion by a developing solution such as an alkaline
aqueous solution, and further a phosphor pattern is formed by
removing the organic component by calcination, there sometimes
causes problems of changes in emission characteristics (such as
emission luminance and chroma) of phosphors.
SUMMARY OF THE INVENTION
[0012] An object of the present invention is to provide a phosphor
pattern having less change in emission characteristics with good
yield.
[0013] Another object of the present invention is to provide a
process for preparing a phosphor pattern having less change in
emission characteristics with good yield.
[0014] Further object of the present invention is to provide an
organic alkali developer for forming a phosphor pattern which can
prepare a phosphor pattern having less change in emission
characteristics with good yield.
[0015] Still further object of the present invention is to provide
an emulsion developer for forming a phosphor pattern which can
prepare a phosphor pattern having less change in emission
characteristics with good yield.
[0016] Moreover, an object of the present invention is to provide a
back plate for a plasma display panel provided with a phosphor
pattern having less change in emission characteristics.
[0017] The first invention relates to a phosphor pattern which
comprises a calcination product of a phosphor pattern precursor
containing (A) an organic material containing at least one selected
from the group consisting of an alkali metal and an alkaline earth
metal; and (B) a phosphor wherein an amount of the alkali metal or
the alkaline earth metal is 2% by weight or less based on the
amount of (B) the phosphor.
[0018] The second invention relates to a process for preparing a
phosphor pattern which comprises the steps of preparing a phosphor
pattern precursor containing
[0019] (A) an organic material containing at least one selected
from the group consisting of an alkali metal and an alkaline earth
metal and
[0020] (B) a phosphor
[0021] in which an amount of the alkali metal or the alkaline earth
metal is 2% by weight or less based on the amount of (B) the
phosphor, and calcining the precursor.
[0022] The third invention relates to a process for preparing a
phosphor pattern as mentioned above, wherein the phosphor pattern
precursor is formed by applying the photolithography method
carrying out a wet development using (C) an alkali developer to a
photosensitive resin composition containing a phosphor.
[0023] The fourth invention relates to a process for preparing a
phosphor pattern as mentioned above, wherein the phosphor pattern
precursor is formed by applying the photolithography method
carrying out a wet development using an emulsion developer
containing water and a solvent to a photosensitive resin
composition containing a phosphor.
[0024] The fifth invention relates to a process for preparing a
phosphor pattern as mentioned above, wherein the phosphor pattern
precursor is formed by applying the photolithography method
carrying out a wet development using an organic alkali developer to
a photosensitive resin composition containing the phosphor.
[0025] The sixth invention relates to an organic alkali developer
for forming a phosphor pattern containing an aliphatic amine, an
aromatic amine or a tetraalkyl ammonium hydroxide.
[0026] The seventh invention relates to an emulsion developer for
forming a phosphor pattern comprising an emulsion containing water
and a solvent.
[0027] The eighth invention relates to a back plate for a plasma
display panel provided with the above-mentioned phosphor pattern on
the substrate for the plasma display panel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a schematical view showing respective steps for
preparing a phosphor pattern.
[0029] FIG. 2 is a schematical view showing one example of a
substrate for PDP to which a barrier rib is formed.
[0030] FIG. 3 is also a schematical view showing one example of a
substrate for PDP to which a barrier rib is formed.
[0031] FIG. 4 is a schematic view showing one example of a plasma
display panel of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] In the following, the present invention is explained in
detail.
[0033] The phosphor pattern of the present invention can be
prepared by calcining a phosphor pattern precursor which
comprises
[0034] (A) an organic material containing at least one selected
from the group consisting of an alkali metal and an alkaline earth
metal and
[0035] (B) a phosphor
[0036] in which an amount of the alkali metal or the alkaline earth
metal is 2% by weight or less based on the amount of (B) the
phosphor.
[0037] In the present invention, the phosphor pattern precursor can
be prepared by coating a paste containing (A) an organic material
such as an organic polymer binder, a compound (curing agent) having
a functional group such as a vinyl group, a hydroxyl group, a
carboxyl group, an epoxy group, an amino group, etc., a solvent,
etc. and (B) a phosphor as essential components on a substrate for
a plasma display panel by a screen printing method, a gravue
coating method, etc., with a pattern state, and drying and curing
under heating, if necessary.
[0038] For obtaining a pattern shape with high resolution, a
phosphor pattern precursor can be formed by applying a
photolithographic method to a photosensitive paste in which a
phosphor is added to a photoresist.
[0039] Also, in view of forming a pattern with finer resolution,
phosphor-formability to wall surface of a barrier rib and
operatability, a phosphor pattern precursor can be formed by
laminating a dry film (photosensitive element) having a
photosensitive resin composition layer containing a phosphor on a
substrate for a plasma display panel and applying a
photolithographic method thereto.
[0040] As (A) the alkali metal or the alkaline earth metal in the
present invention, examples thereof may include lithium, sodium,
potassium, beryllium, magnesium, calcium, barium, rubidium, cesium,
francium, strontium and radium, and they may exist in the form of a
single material, or in the form of an organic acid salt or
inorganic acid salt such as chloride, fluoride, bromide, iodide,
hydroxide, sulfate, carbonate, bicarbonate, phosphate,
pyrophosphate, saturated aliphatic acid salt, unsaturated aliphatic
acid salt, aliphatic dibasic acid salt, aromatic dibasic acid salt,
aliphatic tribasic acid salt, aromatic tribasic acid salt, etc.
[0041] Specific alkali metal salts or alkaline earth metal salts of
the above-mentioned (A) may include, for example, sodium chloride,
sodium bromide, sodium iodide, sodium hydroxide, sodium carbonate,
sodium bicarbonate, sodium phosphate, sodium pyrophosphate, sodium
acetate, sodium lactate, sodium fumarate, sodium benzoate, sodium
terephthalate, sodium citrate, sodium sulfate, potassium chloride,
potassium bromide, potassium iodide, potassium hydroxide, potassium
carbonate, potassium bicarbonate, potassium phosphate, potassium
pyrophosphate, potassium acetate, potassium glycolate, potassium
fumarate, potassium benzoate, potassium terephthalate, potassium
citrate, potassium sulfate, lithium chloride, lithium bromide,
lithium hydroxide, lithium carbonate, lithium acetate, lithium
lactate, lithium tartarate, lithium pyruvate, lithium sulfate,
magnesium chloride hexahydrate, magnesium bromide hexahydrate,
magnesium hydroxide, magnesium hydrogen carbonate, magnesium
phosphate octahydrate, magnesium succinate, magnesium oleate,
magnesium sulfate, calcium chloride, calcium bromide, calcium
iodide hydrate, calcium hydroxide, calcium carbonate, calcium
phosphate, calcium pyrophosphate, calcium acetate, calcium lactate
pentahydrate, calcium citrate tetrahydrate, calcium formate,
calcium gluconate, calcium salicylate dihydrate, calcium tartarate,
calcium sulfate dihydrate, barium chloride, barium carbonate,
barium acetate, barium hydrogen phosphate, barium hydroxide
octahydrate, barium lactate, barium stearate, barium sulfate,
sodium fluoride, potassium fluoride, lithium fluoride, magnesium
fluoride, calcium fluoride, rubidium bromide, rubidium chloride,
rubidium hydroxide, rubidium iodide, rubidium nitrate, rubidium
sulfate, strontium acetate, strontium bromide hexahydrate,
strontium carbonate, strontium chloride, strontium fluoride,
strontium iodide, strontium sulfate, strontium oxalate, strontium
hydroxide octahydrate, strontium di(methoxyethoxide), beryllium
hydroxide, beryllium oxide, beryllium sulfate, etc. These can exist
in a phosphor pattern precursor singly or in combination of two or
more.
[0042] The phosphor (B) used in the present invention is not
particularly limited and those mainly comprising metal oxide can be
used.
[0043] As a phosphor which emits red light (red phosphor), there
may be mentioned, for example, Y.sub.2O.sub.2S:Eu,
Zn.sub.3(PO.sub.4).sub.2:Mn, Y.sub.2O.sub.3:Eu, YVO.sub.4:Eu,
(Y,Gd)BO.sub.3:Eu, .gamma.-Zn.sub.3(PO.sub.4).sub.2:Mn,
(Zn,Cd)S:Ag+In.sub.2O.sub.3, etc.
[0044] As a phosphor which emits green light (green phosphor),
there may be mentioned, for example, ZnS:Cu, Zn.sub.2SiO.sub.4:Mn,
ZnS:Cu+Zn.sub.2SiO.sub.4:Mn, Gd.sub.2O.sub.2S:Tb,
Y.sub.3Al.sub.5O.sub.12- :Ce, ZnS:Cu,Al, Y.sub.2O.sub.2S:Tb,
ZnO:Zn, Zn.sub.2GeO.sub.4:Mn, ZnS:Cu,Al+In.sub.2O.sub.3,
LaPO.sub.4:Ce,Tb, BaO.6Al.sub.2O.sub.3:Mn, etc.
[0045] As a phosphor which emits blue light (blue phosphor), there
may be mentioned, for example, ZnS:Ag, ZnS:Ag,Al, ZnS:Ag,Ga,Al,
ZnS:Ag,Cu,Ga,Cl, ZnS:Ag+In.sub.2O.sub.3,
Ca.sub.2B.sub.5O.sub.9Cl:Eu.sup.2+,
(Sr,Ca,Ba,Mg).sub.10(PO.sub.4).sub.6Cl.sub.2:Eu.sup.2+,
Sr.sub.10(PO.sub.4).sub.6Cl.sub.2:Eu.sup.2+,
BaMgAl.sub.10O.sub.17:Eu.sup- .2+, BaMgAl.sub.14O.sub.23:Eu.sup.2+,
BaMgAl.sub.16O.sub.26:Eu.sup.2+, etc.
[0046] In the present invention, the content of the alkali metal or
the alkaline earth metal contained in (A) of the phosphor pattern
precursor is made each 20 mg (2% by weight) or less based on 1 g of
the phosphor (provided that the alkali metal or the alkaline earth
metal constituting the phosphor is excluded from the above
content). The terms "each 20 mg or less" mean that each one kind of
the alkali metal and the alkaline earth metal is required to be 20
mg or less, or they do not mean that the total amount thereof is 20
mg or less. When two or more kinds of the above metals exist, the
total content thereof is preferably 50 mg or less. When the content
of the alkali metal or the alkaline earth metal exceeds 20 mg (2%
by weight), emission characteristics (emission luminance and
chroma) of phosphors after calcination of the phosphor pattern
precursor change. Also, the content of the alkali metal or the
alkaline earth metal is preferably 1% by weight or less, more
preferably 0.1% by weight or less, particularly preferably 0.03% by
weight or less in view of the point that an effect of inhibiting
change in emission characteristics of the phosphor is remarkable.
The content of the alkali metal or the alkaline earth metal can be
measured by the atomic-absorption spectroscopy, etc.
[0047] In the present invention, a phosphor pattern can be obtained
by calcining the phosphor pattern precursor. The phosphor pattern
precursor means a pattern with a predetermined shape containing the
organic material such as an organic polymer binder, etc. and the
phosphor (B) before the step of calcination as essential
components.
[0048] In the present invention, as a method of making the content
of the alkali metal or the alkaline earth metal in the phosphor
pattern precursor 2% by weight or less, when a phosphor pattern
precursor is formed on the substrate by using a paste containing an
organic material such as an organic polymer binder, etc. and a
phosphor as essential components, the following methods can be
used. For example the method in which an organic material such as
an organic polymer binder which contains no alkali metal nor
alkaline earth metal and a phosphor (provided that the alkali metal
or the alkaline earth metal constituting the phosphor is excluded)
is used and a phosphor pattern precursor is formed by applying a
printing method such as a screen printing, etc., or a coating
method using a dispenser, etc.; the method in which the mixture of
an organic material such as an organic polymer binder and a
phosphor is applied to column chromatography, reprecipitation
method, filtration, etc. to remove the alkali metal or the alkaline
earth metal, then the above-mentioned patterning is carried out to
form a phosphor pattern precursor; and the method in which the
alkali metal or the alkaline earth metal is removed by subjecting
the phosphor pattern precursor formed on the substrate to acid
treatment; etc. may be mentioned.
[0049] When the phosphor pattern precursor is formed by applying
the photolithographic method which effects wet development using
various kinds of developers, there may be mentioned, for example,
the method in which development is carried out by using an emulsion
developer containing water and a solvent during the development
step; the method in which development is carried out by using an
organic alkali developer; the method in which development is
carried out by using water as a developer; and the method in which
after development is carried out by using an alkali developer (a
developer containing the alkali metal or the alkaline earth metal
such as sodium carbonate aqueous solution, etc;), the resulting
material is subjected to acid treatment to remove the alkali metal
or the alkaline earth metal; etc., may be mentioned.
[0050] As the acid to be used as the above-mentioned acid
treatment, there may be mentioned, for example, an organic acid (a
saturated aliphatic acid, an unsaturated aliphatic acid, an
aliphatic dibasic acid, an aromatic dibasic acid, an aliphatic
tribasic acid, an aromatic tribasic acid, an amino acid, an onium
salt, etc.), an inorganic acid such as a Lewis acid, etc.
[0051] Specific examples of the organic acid may include, for
example, formic acid, acetic acid, chloroacetic acid,
dichloroacetic acid, trichloroacetic acid, propionic acid, capric
acid, undecanoic acid, lauric acid, tridecanoic acid, myristic
acid, pentadecanoic acid, palmitic acid, heptadecanoic acid,
stearic acid, nonadecanoic acid, arachidic acid, palmitoleic acid,
oleic acid, elaidic acid, linolenic acid, linoleic acid, oxalic
acid, malonic acid, methylmalonic acid, ethylmalonic acid,
monomethyl malonate, monoethyl malonate, succinic acid,
methylsuccinic acid, adipic acid, methyladipic acid, pimelic acid,
suberic acid, azelaic acid, sebacic acid, maleic acid, itaconic
acid, phthalic acid, isophthalic acid, terephthalic acid,
trimellitic acid, citric acid, salicylic acid, pyruvic acid, malic
acid, aspartic acid, anisic acid, metanilic acid, sulfanilic acid,
anthranilic acid, 2-aminoethylphosphonic acid, 4-aminobutyric acid,
benzoic acid, isonicotinic acid, methyl isonicotinate, 2-indol
carboxylic acid, oxaloacetic acid, glyoxylic acid, glycolic acid,
glycerin phosphoric acid, glucose-1-phosphoric acid, reduced type
glutathione, glutamic acid, glutaric acid, chlorobenzoic acid,
2-chloropripionic acid, cinnamic acid, sarcosine, cyanobenzoic
acid, cyanoacetic acid, 2,4-diaminobutyric acid, dichloroacetic
acid, N,N-dimethylglycine, penicillamine, tartaric acid,
thioglycolic acid, trichloroacetic acid, naphthoic acid,
nitrobenzoic acid, lactic acid, barbituric acid, picric acid,
picolinic acid, hydroxybenzoic acid, vinylacetic acid,
2,6-pyridinecarboxylic acid, phenylacetic acid, fumaric acid,
2-furancarboxylic acid, fluorobenzoic acid, fluoroacetic acid,
bromobenzoic acid, hexafluoroacetylacetone, mandelic acid,
mercaptobenzoic acid, iodobenzoic acid, iodoacetic acid, levulinic
acid, glycine, alanine, valine, leucine, isoleucine, phenylalanine,
asparagine, glutamine, tryptophane, proline, serine, threonine,
thirosine, hydroxyproline, cysteine, cystine, methionine, aspartic
acid, glutamic acid, lysine, arginine, histidine, ammonium acetate,
ammonium adipate, ammonium arginate, ammonium amidesulfate,
ammonium benzoate, ammonium bifluoride, ammonium bisulfate,
ammonium bisulfite, ammonium hydrogen tartarate, ammonium bromide,
ammonium chloride, diammonium citrate, triammonium citrate,
ammonium diethyldithiocarbamate, ammonium dihydrogen phosphate,
ammonium fluoride, ammonium borofluoride, ammonium formate,
ammonium hexafluorophosphate, ammonium hydrogen fluoride, ammonium
hydrogen tartarate, ammonium iodide, ammonium lactate, ammonium
persulfate, diammonium phosphate, monoammonium phosphate,
triammonium phosphate, ammonium phthalate, ammonium succinate,
ammonium sulfite, ammonium thiocyanate, ammonium thiosulfate,
dimethylamine hydrochloride, diethylamine hydrochloride,
dibutylamine hydrochloride, trimethylamine hydrochloride,
triethylamine hydrochloride, tributylamine hydrochloride, etc.
Also, specific inorganic acid may include, for example, sulfuric
acid, hydrochloric acid, nitric acid, phosphoric acid, etc.
[0052] Also, as the acid for the acid treatment, the quaternary
ammonium salt having a cationic property on the nitrogen atom
represented by the following formula (III) which is a Lewis acid:
1
[0053] wherein R represents an alkyl group having 1 to 10 carbon
atoms, a benzyl group, a phenyl group or an alkyleneoxy group
having 1 to 4 carbon atoms, a plural number of R's may be the same
or different from each other; X represents a group in which one
hydrogen atom is removed from either of the above-mentioned
saturated aliphatic acids, a group in which one hydrogen atom is
removed from either of the above-mentioned unsaturated aliphatic
acids, a group in which one hydrogen atom is removed from either of
the above-mentioned inorganic acids, a halogen atom or a
halogenated compound, and p is an integer of 1 to 3,
[0054] or the quaternary phosphonium salt having a cationic
property on the phosphorus atom represented by the following
formula (IV): 2
[0055] wherein R, X and p have the same meanings as defined in the
formula (III),
[0056] can be used.
[0057] Specific examples of such quaternary ammonium salts or
quaternary phosphonium salts may include, for example,
tetrabutylammonium fluoride, tetrabutylammonium borofluoride,
tetramethylammonium chloride, tetraethylammonium chloride,
tetrabutylammonium chloride, tetrapentylammonium chloride,
tetraoctylammonium chloride, benzyltriethylammonium chloride,
benzyltributylammonium chloride, tetraethylammonium perchlorate,
tetrabutylammonium perchlorate, tetramethylammonium bromide,
tetraethylammonium bromide, tetrabutylammonium bromide,
tetrabutylammonium tribromide, benzyltrimethylammonium tribromide,
tetramethylammonium iodide, tetraethylammonium iodide,
tetrabutylammonium iodide, benzyltrimethylammonium iodide,
tetraethylammonium acetate, tetrabutylammonium acetate,
tetraethylammonium formate, tetrabutylammonium formate,
tetramethylammonium formate, tetrabutylammonium dihydrogen
phosphate, tetra- butylammonium hydrogen borocyanide,
tetrabutylammonium borohydride, tetrabutylammonium hydrogen
sulfate, tetrabutylammonium nitrate, tetrabutylammonium phosphate,
tetrabutylammonium tetrafluoroborate, benzyltrimethylammonium
dibromohydrochloride, trimethylammonium hexafluorophosphate,
benzyltrimethylammonium tetrachlorohydroiodide, tetramethylammonium
tetrafluoroborate, tetraethylammonium tetrafluoroborate,
tetrabutylphosphonium chloride, benzyltriphenylphosphonium
chloride, tetrabutylphosphonium bromide, etc. These materials may
be used singly or in combination of two or more.
[0058] Among these, tetramethylammonium chloride,
tetraethylammonium chloride, tetrabutylammonium chloride,
tetramethylammonium bromide, tetraethylammonium bromide,
tetrabutylammonium bromide, tetraethylammonium acetate,
tetrabutylammonium acetate, tetraethylammonium formate,
tetrabutylammonium formate, tetramethylammonium formate,
tetramethylammonium acetate, benzyltriethylammonium chloride and
benzyltributylammonium chloride are preferred in view of the points
that damage by the acid treatment to the surface of the dielectric
layer constituted from a metal such as Mg, Si, Ca, Al, Zn, Pb, etc.
and oxides thereof formed on the substrate for PDP can be made
small, and roughening, crack, etc. can be inhibited.
[0059] The acid treatment can be carried out by using a solution
(an acid solution) (the concentration of the acid is preferably
0.01 to 50% by weight, more preferably 1 to 10% by weight or so) in
which the above-mentioned acid is dissolved in a solvent(water
and/or a solvent), at a solution temperature of 10 to 80.degree. C.
or so for 1 to 180 minutes or so applying thereto the known methods
such as spraying, dipping by rocking, brushing, scrapping, etc. A
pH of the acid solution to be used in the acid treatment is
preferably made 2 to 7. The pH and the temperature of the acid
aqueous solution, and the treatment time can be adjusted depending
on the phosphor pattern precursor and the acid resistance of the
substrate for the PDP (durability against the acid, which does not
deteriorate by the acid).
[0060] Further, after the acid treatment, a step of washing with
water may be performed.
[0061] The solvent to be used in the acid solution is not
particularly limited but the following can be exemplified.
[0062] Examples may include a glycol type solvent such as
1,2-diethoxyethane, 1,2-dibutoxyethane, diethylene glycol dimethyl
ether, diethylene glycol diethyl ether, diethylene glycol dibutyl
ether, 2-(isopentyloxy)ethanol, 2-(isohexyloxy)ethanol,
2-phenoxyethanol, 2-(benzyloxy)ethanol, diethylene glycol monobutyl
acetate, etc.; an aromatic type solvent such as toluene, xylene,
ethylbenzene, cumene, mesitylene, butylbenzene, p-cymene,
diethylbenzene, pentylbenzene, dipentylbenzene, tetraline,
pyridine, .alpha.-picoline, .beta.-picoline, .gamma.-picoline,
2,4-lutidine, 2,6-lutidine, quinoline, etc.; an ester type solvent
such as ethyl formate, propyl formate, butyl formate, isopropyl
formate, pentyl formate, methyl acetate, ethyl acetate, propyl
acetate, isopropyl acetate, butyl acetate, isobutyl acetate,
sec-butyl acetate, pentyl acetate, isopentyl acetate, sec-hexyl
acetate, methyl propionate, ethyl propionate, butyl propionate,
isopentyl propionate, methyl butyrate, ethyl butyrate, butyl
butyrate, isopentyl butyrate, butyl isobutyrate, ethyl
2-hydroxy-2-methylpropionate, methyl isovalerinate, isopentyl
isovalerinate, methyl benzoate, ethyl benzoate, propyl benzoate,
butyl benzoate, isopentyl benzoate, 2-ethylbutyl acetate,
2-ethylhexyl acetate, cyclohexyl acetate, benzyl acetate,
3-methoxybutyl acetate, 3-methyl-3-methoxymethoxybutyl acetate,
.gamma.-butyrolactone, ethylene glycol monolauric acid ester,
ethylene glycol monomyristic acid ester, ethylene glycol
monopalmitic acid ester, ethylene glycol monomargaric acid ester,
ethylene glycol monostearic acid ester, glycerine triacetate,
glycerine monobutyrate, diethyl carbonate, butyl lactate, pentyl
lactate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, methyl
acetoacetate, ethyl acetoacetate, etc.; a ketone type solvent such
as cyclopentanone, cyclohexanone, methylcyclohexanone,
acetophenone, camphor, 2-pentanone, 3-pentanone, 2-hexanone, methyl
isobutyl ketone, 2-pentanone, 4-heptanone diisobutyl ketone,
acetonylacetone, etc.; an alcohol type solvent such as 1-butanol,
2-butanol, isobutyl alcohol, 1-pentanol, 2-pentanol, 3-pentanol,
2-methyl-1-butanol, isopentyl alcohol, tert-pentyl alcohol,
3-methyl-2-butanol, neopentyl alcohol, 1-hexanol,
2-methyl-1-pentanol, 4-methyl-2-pentanol, 2-ethyl-1-butanol,
1-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol,
1-nonanol, 3,5,5-trimethyl-1-hexanol, 1-decanol, 1-undecanol,
1-dodecanol, benzylalcohol, cyclohexanol, 1-methylcyclohexanol,
2-methylcyclohexanol, 3-methylcyclohexanol, 4-methylcyclohexanol,
1,2-butanediol, 2-ethyl-1,3-hexanediol, etc.; an ether type solvent
such as diethyl ether, dipropyl ether, diisopropyl ether, dibutyl
ether, dihexyl ether, anisol, phenetol, butylphenyl ether,
pentylphenyl ether, methoxytoluene, benzylethyl ether, diphenyl
ether, dibenzyl ether, veratrol, propylene oxide, dioxane,
trioxane, tetrahydrofuran, tetrahydropyran, cineole, etc.
[0063] These solvents may be used singly or in combination of two
or more.
[0064] In the present invention, when a pattern is formed by using
an alkali developer (a developer containing an alkali metal or an
alkaline earth metal) to effect wet development by the
photolithography method, the alkali metal or the alkaline earth
metal remains in the pattern after development so that the acid
treatment is effectively carried out to remove these metals.
[0065] As the above alkali developer, there may be mentioned a
solution in which an alkali hydroxide (hydroxide of lithium, sodium
or potassium, etc.), an alkali carbonate (carbonate or bicarbonate
of lithium, sodium or potassium, etc.), an alkali metal phosphate
(potassium phosphate, sodium phosphate, etc.), an alkali metal
pyrophosphate (sodium pyrophosphate, potassium pyrophosphate,
etc.), etc. is/are dissolved in a solvent, and of these, preferred
is a solution in which sodium carbonate, potassium carbonate, etc.
is/are dissolved in a solvent (water and/or a solvent). The solvent
is preferably water in the points that it is harmless to
environment and the waste solution can be easily treated.
[0066] A pH of the alkali developer to be used in the development
is preferably 9 to 11, and the temperature of the same can be
adjusted depending on developability of a photosensitive resin
composition containing a phosphor.
[0067] Also, to the alkali developer, a surfactant, a deforming
agent, and a small amount of a solvent which accelerates the
development may be added.
[0068] Components for constituting the photosensitive resin
composition containing a phosphor of the present invention are not
particularly limited and can be constituted by a photosensitive
resin composition generally used for the photolithographic method.
In the points of photosensitivity and workability, those containing
(a) a film-forming property-providing polymer, (b) a
photopolymerizable unsaturated compound having an ethylenic
unsaturated group, (c) a photopolymerization initiator and (d) a
phosphor as described in Japanese Provisional Patent Publication
No. 265906/1997 are preferred.
[0069] In order to realize development of the photosensitive resin
composition containing a phosphor of the present invention by
various kinds of developers, a content of a carboxyl group (which
can be regulated by an acid value (mg KOH/g)) of the film-forming
property-providing polymer can be optionally controlled.
[0070] For example, when development is carried out by using an
organic alkali developer, the acid value is preferably made 90 to
260. If the acid value is less than 90, development is tend to be
difficult, while if it exceeds 260, developer resistance (a
property in which a portion which becomes a remaining pattern
without removing by the development is not removed by the
developer) is tend to be lowered.
[0071] When development is carried out by using an alkali developer
or by using water, the acid value is preferably made 16 to 260. If
the acid value is less than 16, development is tend to be
difficult, while if it exceeds 260, developer resistance is tend to
be lowered.
[0072] When development is carried out by using an emulsion
developer comprising water and a solvent (preferably one or more
solvents which do not dissolve in water), the film-forming
property-providing polymer may not have a carboxyl group.
[0073] As the above-mentioned phosphor (d), the above-mentioned
phosphor (B) may be mentioned.
[0074] A formulation amount of the above-mentioned component (a) is
preferably 10 to 90 parts by weight, more preferably 20 to 80 parts
by weight based on the total weight of the component (a) and the
component (b) being made 100 parts by weight. If the amount is less
than 10 parts by weight, when it is supplied in a roll state as a
photosensitive element, the photosensitive resin composition
containing a phosphor is oozed out from the edge portion of the
roll (hereinafter referred to this phenomenon as "edge fusion") so
that the roll can hardly be dispatched when laminating the
photosensitive element, and the oozed out portion is partially
excessively buried in the space of the substrate for PDP whereby
causing the problem that a production yield is remarkably lowered,
etc. or there is a tendency of lowering in film-forming property If
it exceeds 90 parts by weight, sensitivity is tend to be
insufficient.
[0075] A formulation amount of the above-mentioned component (b) is
preferably 10 to 90 parts by weight, more preferably 20 to 80 parts
by weight based on the total weight of the component (a) and the
component (b) being made 100 parts by weight. If the amount is less
than 10 parts by weight, sensitivity of the photosensitive resin
composition containing a phosphor tend to be insufficient, while if
it exceeds 90 parts by weight, the photocured product is tend to be
brittle, and when a photosensitive element is made, the
photosensitive resin composition containing a phosphor is oozed out
from the edge portion due to its fluidity or a film-forming
property is tend to be lowered.
[0076] A formulation amount of the above-mentioned component (c) is
preferably 0.01 to 30 parts by weight, more preferably 0.1 to 20
parts by weight based on the total weight of the component (a) and
the component (b) being made 100 parts by weight. If the amount is
less than 0.01 part by weight, sensitivity of the photosensitive
resin composition containing a phosphor tend to be insufficient,
while if it exceeds 30 parts by weight, absorption of an active
light at the exposed surface of the photosensitive resin
composition containing a phosphor is increased whereby photocuring
at the inner portion is tend to be insufficient.
[0077] A formulation amount of the above-mentioned component (d) is
preferably 10 to 500 parts by weight, more preferably 10 to 400
parts by weight, particularly preferably 10 to 300 parts by weight,
most preferably 50 to 250 parts by weight based on the total weight
of the component (a), the component (b) and the component (c) being
made 100 parts by weight. If the amount is less than 10 parts by
weight, when it is emitted as a PDP, an emission efficiency is tend
to be lowered, while if it exceeds 500 parts by weight, when it is
made as a photosensitive element, a film-forming property or
flexibility is tend to be lowered.
[0078] In the present invention, in the photolithographic method,
when wet development is carried out to form a phosphor pattern
precursor, a method of subjecting to wet development using an
organic alkali developer is effective.
[0079] As the above-mentioned organic alkali developer, there may
be mentioned a solution in which an organic alkali is dissolved in
water, a solution in which an organic alkali is dissolved in a
solvent or a solution in which an organic alkali is dissolved in a
mixture of water and a solvent. As the organic alkali, there may be
mentioned an aliphatic amine, an aromatic amine, tetraalkyl
ammonium hydroxide, etc.
[0080] As the above-mentioned aliphatic amine, examples may
include, for example, methylamine, ethylamine, propylamine,
isopropylamine, butylamine, isobutylamine, sec-butylamine,
tert-butylamine, 1,4-butanediamine, cyclohexylamine,
1,6-hexanediamine, hexylamine, benzylamine, phenylethylamine,
2-amino-2-hydroxymethyl-1,3-propanediol,
1,3-diamino-propanol-2-morpholine, dimethylamine, diethylamine,
dipropylamine, N-methylamine, trimethylamine, triethylamine,
tripropylamine, N,N-dimethylamine, N,N-dimethylethyleneamine,
ethanolamine, diethanolamine, triethanolamine,
tris(hydroxymethyl)methyla- mine, dimethylamine, ethylenediamine,
diethylenetriamine, etc.
[0081] As the above-mentioned aromaticamine, there may be mentioned
aniline, dimethylaniline, toluidine, phenylenediamine, anisidine,
etc.
[0082] Specific tetraalkylammonium hydroxide may include
tetramethylammonium hydroxide, tetraethylammonium hydroxide,
tetrabutylammonium hydroxide, benzyltrimethylammonium hydroxide,
benzyltriethylammonium hydroxide, benzyltributylammonium hydroxide,
etc.
[0083] These organic amines may be used singly or in combination of
two or more.
[0084] Among these, tetramethylammonium hydroxide,
tetraethylammonium hydroxide, tetrabutylammonium hydroxide, etc.
are preferably used.
[0085] In addition to the above-mentioned developers, a solution in
which ammonium hydroxide is dissolved in water, a solution in which
ammonium hydroxide is dissolved in a solvent, or a solution in
which ammonium hydroxide is dissolved in a mixed solution of water
and a solvent may by used.
[0086] A pH of the organic alkali developer to be used in the
development is preferably made 9 to 11. The content of the organic
alkali is preferably 0.01 to 15% by weight based on the total
weight of the organic developer in view of developability. Also,
the temperature of the same can be adjusted depending on
developability of a photosensitive resin composition containing a
phosphor.
[0087] Also, to the organic alkali developer, a surfactant, a
deforming agent, and a small amount of a solvent which accelerates
the development may be added.
[0088] As the above-mentioned solvent, there may be mentioned, for
example, acetone alcohol, acetone, ethyl acetate, an alkoxy ethanol
having an alkoxy group with 1 to 4 carbon atoms, ethyl alcohol,
isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl
ether, diethylene glycol monoethyl ether, diethylene glycol
monobutyl ether, triethylene glycol monobutyl ether, dipropylene
glycol monomethyl ether, dipropylene glycol monopropyl ether,
3-methyl-3-methoxybutylacetate, 1,1,1-trichloroethane,
N-methyl-2-pyrrolidone, N,N-dimethylformamide, cyclohexanone,
methyl isobutyl ketone, .gamma.-butyrolactone, etc. These solvents
may be used singly or in combination of two or more.
[0089] In the present invention, in view of workability, an
emulsion developer containing water and a solvent may be used in
place of the above-mentioned organic alkali developer.
[0090] The emulsion developer is preferably mixed with at least one
kind of a surfactant (hereinafter referred to "surfactants")
depending on necessity and further at least one kind of a
polymerization inhibitor depending on necessity.
[0091] The mixing ratio of the respective components is preferably
(1) 1 to 99% by weight of water, (2) 1 to 99% by weight of a
solvent and (3) 0 to 30% by weight of a surfactant, more preferably
(1) 10 to 80% by weight of water, (2) 20 to 90% by weight of a
solvent and (3) 0 to 30% by weight of a surfactant, particularly
preferably (1) 10 to 70% by weight of water, (2) 30 to 85% by
weight of a solvent and (3) 0 to 20% by weight of a surfactant. If
the mixing ratio of water is less than 1% by weight or the mixing
ratio of the solvent exceeds 99% by weight, inflammability,
toxicity and swellability are tend to be increased. If the mixing
ratio of water exceeds 99% by weight or the mixing ratio of the
solvent is less than 1% by weight, lipophilic property and
developability are tend to be impaired. When the mixing ratio of
the surfactant exceeds 30% by weight, emulsion cannot be formed and
the liquid is tend to become a uniform solution.
[0092] Particularly preferred solvent to be used in the emulsion
developer may include the above-mentioned glycol type solvent,
aromatic type solvent, ester type solvent, ketone type solvent,
alcohol type solvent and ether type solvent.
[0093] As the solvent to be used in the emulsion developer, those
having 4 to 30 carbon atoms and a boiling point of 60 to
350.degree. C. are preferred and those having 4 to 20 carbon atoms
and a boiling point of 60 to 280.degree. C. are more preferred. Any
solvents in which the carbon number or the boiling point is out of
the above range involve the problem that developability is tend to
be lowered.
[0094] In view of developability, solubility of water in a solvent
(at the temperature of the developer when development is carried
out) is preferably 30% by weight or less and/or solubility of a
solvent in water at the temperature when it is used is preferably
30% by weight or less.
[0095] The above-mentioned surfactant preferably has a total carbon
number of a hydrophobic organic group(s) is 8 to 50, more
preferably 12 to 25. In the total carbon number of the hydrophobic
organic group, carbons of an organic group having hydrophilic
property such as a polyoxyethylene group are not included.
[0096] As the above-mentioned surfactant, there may be specifically
mentioned (1) anionic surfactants such as salts of
alkylbenzenesulfonic acid derivatives, alkylnaphthalenesulfonic
acid derivatives or alkylsulfosuccinic acid derivatives each having
hydrophobic alkyl chain with the total carbon number of 8 to 30, or
a mixture thereof; (2) cationic surfactants such as quaternary
ammonium salts having the total carbon number of 8 to 50, or a
mixture thereof; and (3) nonionic surfactants such as
polyoxyethylene aliphatic acid esters, polyoxyethylenesorbitane
aliphatic acid ester, polyoxyethylene alkyl ether, polyoxyethylene
alkyl aryl ether or a mixture thereof. Among these surfactants, at
least one selected from the above surfactants and having an HLB
(hydrophilic-lipophilic balance) value within the range of 2.8 to
50 is preferably used.
[0097] The anionic surfactants preferably have a hydrophobic alkyl
chain with the total carbon number within the range of 10 to 20,
more preferably 12 to 20. Also, as a pair ion, a quaternary
ammonium is preferred.
[0098] As the quaternary ammonium salt suitably used as the
cationic surfactants, among the range of the total carbon number as
mentioned above, those having 9 to 25 are particularly excellent.
As a pair anion, a sulfonic acid ion, an organic sulfonic acid ion,
a halogen ion, a phosphoric acid ion, an organic phosphoric acid
ion, etc. are suitable. As the nonionic surfactants, those having a
polyoxyethylene group are preferred and those in which a
polymerization degree of the polyoxyethylene is in the range of 2
to 100 are more preferred. In the above-mentioned total number of
carbon atoms of the hydrophobic alkyl chain in the above-mentioned
anionic surfactant, the carbon atoms which constitute an aromatic
nucleus are not contained, and the HLB value is calculated from the
Davis method.
[0099] As the above-mentioned polymerization inhibitor, specific
examples may include hydroquinone, hydroquinone monomethyl ether,
benzoquinone, pyrogallol, chatechol, chatechol amine, derivatives
thereof, etc., and they may be used singly or in combination of two
or more.
[0100] In the following, one example of a process for preparing the
phosphor pattern of the present invention is explained by referring
to FIG. 1. FIG. 1 is a schematic view showing respective steps of
one example of a process for preparing the phosphor pattern of the
present invention, and the reference numeral 1 is a substrate, 2 is
a barrier rib, 5 is a photosensitive resin composition, 5' is a
photosensitive resin composition after photocuring, 6 is an
embedding layer, 8 is a photomask, 9 is an active light and 10 is a
phosphor pattern.
[0101] The phosphor pattern of the present invention can be
prepared by performing at least (I) a step of forming a
photosensitive resin composition layer containing a phosphor on a
substrate having an unevenness, (II) a step of imagewisely
irradiating an active light to the photosensitive resin composition
layer containing a phosphor, (III) a step of selectively removing
by development the photosensitive resin composition layer
containing a phosphor subjected to imagewisely irradiated by an
active light by development to form a pattern, and (IV) a step of
forming a phosphor pattern by removing unnecessary portion from the
above-mentioned phosphor pattern precursor by calcination.
[0102] (I) Step of forming photosensitive resin composition layer
containing phosphor on a substrate having unevenness The
photosensitive resin composition layer containing a phosphor is
formed on the uneven surface of a substrate having unevenness by
using a liquid state or photosensitive element. As a method for
forming the layer, it is not particularly limited, and there may be
mentioned, for example, the method in which a liquid state paste
obtained by uniformly dissolving or dispersing respective
components constituting the photosensitive resin composition layer
containing a phosphor as mentioned above in a solvent which can
dissolve or disperse the components is directly coated on the
uneven surface and dried; the method in which the photosensitive
resin composition layer is formed on the uneven surface by using a
photosensitive element having the photosensitive resin composition
layer containing a phosphor as mentioned above; etc.
[0103] As the substrate having unevenness in the present invention,
a substrate for a plasma display panel (a substrate for PDP) to
which barrier ribs are formed, etc. may be mentioned.
[0104] In FIG. 2 and FIG. 3, one example of the schematic view of a
substrate for PDP in which barrier ribs are formed is shown,
respectively. The barrier rib generally has a height of 20 to 500
.mu.m and a width of 20 to 200 .mu.m. In FIG. 2 and FIG. 3, 3 is a
lattice-shaped discharge space, and 4 is a striped discharge space.
The shape of a discharge space surrounded with the barrier ribs is
not particularly limited and may be lattice-shaped, striped,
honeycomb-shaped, triangular or elliptical. In general, a
lattice-shaped or striped discharge space as shown in FIG. 2 or
FIG. 3 is formed.
[0105] In FIG. 2 and FIG. 3, on a substrate 1, barrier ribs 2 are
formed, and in FIG. 2, a lattice-shaped discharge space 3 is formed
and in FIG. 3, a striped discharge space 4 is formed. The size of
the discharge space is determined by the size and resolution of
PDP. In general, in the lattice-shaped discharge space as shown in
FIG. 2, the longitudinal and lateral lengths are 50 .mu.m to 1 mm,
and in the striped discharge space as shown in FIG. 3, the interval
is 30 .mu.m to 1 mm.
[0106] (II) Step of irradiating active light imagewisely to
photosensitive resin composition layer containing phosphor
[0107] The state of irradiating an active light 9 imagewisely is
shown in FIG. 1 (II). In FIG. 1 (II), as a method for imagewisely
irradiating the active light 9, there may be mentioned a method in
which the active light 9 is imagewisely irradiated through a
photomask 8 such as a negative film, a positive film, etc. placed
on or above the photosensitive resin composition 5 containing a
phosphor in the state as shown in FIG. 1 (I).
[0108] As the active light, there may be preferably used light
generated from a known active light source, for example, a light
generated from carbon arc, mercury vapor arc, xenon arc and
others.
[0109] (III) Step of forming pattern by selectively removing
photosensitive resin composition layer containing phosphor to which
active light is imagewisely irradiated by development
[0110] The state in which an unnecessary portion is removed by
development is shown in FIG. 1 (III). In FIG. 1 (III), 5' is a
photosensitive resin composition containing a phosphor after
photocuring.
[0111] In FIG. 1 (III), as the development method, there may be
mentioned, for example, a method in which, after the state shown in
FIG. 1 (II), when a support film exist on or above the
photosensitive resin composition 5 containing a phosphor, the
support film is removed and then development is carried out by
using a developer by the conventionally known method such as
spraying, dipping by rocking, blushing, scrapping, etc. to remove
the unnecessary portion.
[0112] When an alkali developer is used as the developing solution,
the resulting pattern is subjected to an acid treatment after
development. When an organic alkali developer or an emulsion
developer is used as a developer, it is not particularly required
to effect the acid treatment to the resulting pattern.
[0113] (IV) Step of forming phosphor pattern by removing
unnecessary portion from the above-mentioned phosphor pattern
precursor by calcination.
[0114] The state in which a phosphor pattern is formed, which is
after removing an unnecessary portion by calcination, is shown in
FIG. 1(IV). In FIG. (IV), the reference numeral 10 is a phosphor
pattern.
[0115] In FIG. 1(IV), the calcination method is not particularly
limited, and a phosphor pattern can be formed by removing an
unnecessary portion other than the phosphor and binder by applying
the conventionally known method.
[0116] At the time of calcination, the maximum calcination
temperature is preferably 350 to 800.degree. C., more preferably
400 to 600.degree. C. The calcination maintaining time at the
calcination temperature is preferably 3 to 120 minutes, more
preferably 5 to 90 minutes. The temperature raising rate at this
time is preferably 0.5 to 50.degree. C./min, more preferably 1 to
45.degree. C./min. Also, during the temperature range of 350 to
450.degree. C. which is before reaching to the maximum calcination
temperature, a step of retaining the temperature may be provided,
and the retaining time is preferably 5 to 100 minutes.
[0117] The back plate for the plasma display panel of the present
invention comprises the phosphor pattern obtained as mentioned
above on the substrate for the plasma display panel.
[0118] In the following, a back plate for a plasma display panel is
explained by referring to FIG. 4. FIG. 4 is a schematic drawing
showing one example of a plasma display panel (PDP), and in FIG. 4,
the reference numeral 1 is a substrate, 2 is a barrier rib, 4 is a
striped discharge space, 10 is a phosphor pattern, 11 is an
electrode for address, 12 is a protective film, 13 is a dielectric
layer, 14 is an electrode for display, and 15 is a substrate for a
front plate.
[0119] In FIG. 4, the bottom portion including the substrate 1,
barrier ribs 2, phosphor pattern 10 and electrode for address 11 is
a back plate for PDP, and the upper portion including the
protective film 12, dielectric layer 13, electrode for display 14
and substrate for the front plate is a front plate for PDP.
[0120] PDP can be classified into AC (alternating current) type
PDP, DC (direct current) type PDP, etc. in the point of voltage
applying system, and the schematic drawing of FIG. 4 shown as one
example is an AC type PDP.
[0121] The process for producing the phosphor pattern and the
photosensitive element of the present invention can be applied to a
self-emission type display such as a field emission display (FED),
an electroluminescense display (ELD), etc.
EXAMPLES
[0122] In the following, the present invention is explained by
referring to Examples.
[0123] Preparation Example 1
[0124] (Preparation of Solution (d-1) of Film Property Providing
Polymer)
[0125] In a flask provided with a stirrer, a reflux condenser, an
inactive gas inlet tube and a thermometer was charged a mixed
solvent {circle over (1)}, shown in Table 1, and the temperature of
the solvent was raised to 80.degree. C. under nitrogen atmosphere,
and while maintaining the reaction temperature at 80.degree.
C..+-.2.degree. C., a mixed solution {circle over (2)} (of a
material shown in Table 1 was uniformly added dropwise. After
dropwise addition, stirring was continued at 80.degree.
C.+2.degree. C. for 6 hours to obtain Solution (d-1) (solid
content: 45.5% by weight) of a film property providing polymer
having a weight average molecular weight of 80,000 and an acid
value of 130 mgKOH/g.
1TABLE 1 Formulation Material amount {circle over (1)} Ethylene
glycol 70 parts by monomethyl ether weight Toluene 50 parts by
weight {circle over (2)} Methacrylic acid 20 parts by weight Methyl
methacrylate 55 parts by weight Ethyl acrylate 15 parts by weight
n-Butyl methacrylate 10 parts by weight 2,2'-Azobis(isobutyro- 0.5
parts by nitrile) weight
[0126] Preparation Example 2
[0127] (Preparation of Solution (D-1) for Photosensitive Resin
Composition Layer Containing Phosphor)
[0128] The materials shown in Table 2 were mixed for 15 minutes by
using a stirrer to prepare Solution (D-1) for a photosensitive
resin composition layer containing a phosphor.
2 TABLE 2 Formulated Material amount Solution (d-1) of film
property providing 132 parts by weight polymer obtained in
Preparation example 1 (solid content: 60 parts by weight)
Polypropylene glycol dimethacrylate 40 parts by (average number of
propylene oxide: 12) weight
2-Benzyl-2-dimethylamino-1-(4-morpholino- 1 parts by
phenyl)-butanone-1 weight BaMgAl.sub.14O.sub.23:Eu.sup.2+ (Blue
phosphor) 110 parts by weight Methyl ethyl ketone 30 parts by
weight
[0129] Solution (D-1) for a photosensitive resin composition layer
containing a phosphor obtained in Preparation example 2 was
uniformly coated on the surface of a polyethyleneterephthalate film
with a thickness of 20 .mu.m, and dried with a hot air convection
type drier at 110.degree. C. for 10 minutes to remove the solvent
whereby a photosensitive resin material containing phosphor was
formed. The thickness of the resulting photosensitive resin
material containing phosphors was 50 .mu.m.
[0130] Then, on the photosensitive resin material containing
phosphors, a polyethylene film with a thickness of 25 .mu.m was
further laminated as a cover film to prepare a photosensitive
element (i).
[0131] Preparation Example 3
[0132] (Preparation of Solution (D-2) for Photosensitive Resin
Composition Containing Phosphor)
[0133] In Preparation example 2, the same procedure was repeated
except for changing the materials shown in Table 2 with those shown
in Table 3, to prepare Solution (D-2) for a photosensitive resin
composition containing a phosphor.
3 TABLE 3 Formulated Material amount Solution (d-1) of film
property providing 132 parts by weight polymer obtained in
Preparation example 1 (solid content: 60 parts by weight)
Polypropylene glycol dimethacrylate 40 parts by (average number of
propylene oxide: 12) weight
2-Benzyl-2-dimethylamino-1-(4-morpholino- 2 parts by
phenyl)-butanone-1 weight Zn.sub.2SiO.sub.4:Mn (Green phosphor) 120
parts by weight Malonic acid 0.3 part by weight Methyl ethyl ketone
30 parts by weight
[0134] Solution (D-2) for a photosensitive resin composition layer
containing a phosphor obtained in Preparation example 3 was
uniformly coated on the surface of a polyethyleneterephthalate film
with a thickness of 20 .mu.m, and dried with a hot air convection
type drier at 110.degree. C. for 10 minutes to remove the solvent
whereby a photosensitive resin material containing phosphor was
formed. The thickness of the resulting photosensitive resin
material containing phosphors was 50 .mu.m.
[0135] Then, on the photosensitive resin material containing
phosphors, a polyethylene film with a thickness of 25 .mu.m was
further laminated as a cover film to prepare a photosensitive
element (ii).
[0136] Preparation Example 4
[0137] (Preparation of Solution (D-3) for Photosensitive Resin
Composition Containing Phosphor)
[0138] In Preparation example 2, the same procedure was repeated
except for changing the materials shown in Table 2 with those shown
in Table 4, to prepare Solution (D-3) for a photosensitive resin
composition containing a phosphor.
4 TABLE 4 Formulated Material amount Solution (d-1) of film
property providing 132 parts by weight solid content: 60 parts by
weight) Polypropylene glycol dimethacrylate 40 parts by (average
number of propylene oxide: 12) weight
2-Benzyl-2-dimethylamino-1-(4-morp- holino- 1 parts by
1-phenyl)-butanone-1 weight (Y,Gd)BO.sub.3:Eu (Red phosphor) 212
parts by weight Methyl ethyl ketone 30 parts by weight
[0139] Solution (D-3) for a photosensitive resin composition layer
containing a phosphor obtained in Preparation example 4 was
uniformly coated on the surface of a polyethylenetere film with a
thickness of 20 82 m, and dried with a hot air convection type
drier at 110.degree. C. for 10 minutes to remove the solvent
whereby a photosensitive resin material containing phosphor was
formed. The thickness of the resulting photosensitive resin
material containing phosphors was 50 .mu.m.
[0140] Then, on the photosensitive resin material containing
phosphors, a polyethylene film with a thickness of 25 .mu.m was
further laminated as a cover film to prepare a photosensitive
element (iii).
[0141] Preparation Example 5
[0142] At the side at which barrier ribs are formed on a substrate
for PDP (stripe shaped barrier ribs, opening width between barrier
ribs: 140 .mu.m, width of barrier ribs: 70 .mu.m, and a height of
barrier ribs: 140 .mu.m), the photosensitive element (i) obtained
in Preparation example 2 was laminated by peeling off the
polyethylene film by using a vacuum laminater (available from
Hitachi Chemical Co., Ltd., trade name: VLM-1 Type) at a heat shoe
temperature of 30.degree. C., a laminating rate of 1.5 m/min, a
pressure of 4000 Pa or less and an adhering pressure (cylinder
pressure) of 5.times.10.sup.4 Pa (since a substrate with a
thickness of 3 mm, and a length of 10 cm and a width of 10 cm was
used, a line pressure at this time was 2.4.times.10.sup.3 N/m).
[0143] Next, the polyethylene terephthalate film of the
photosensitive element at the side which is not in contact with the
barrier ribs was peeled off. On the photosensitive layer containing
a phosphor, an embedding layer comprising a polyethylene
terephthalate film with a film thickness of 100 .mu.m (Vicat
softening point: 82 to 100.degree. C.) was contacted and pressed by
using a laminater (available from Hitachi Chemical Co., Ltd., trade
name: HLM-3000 Type) at a laminating temperature of 70.degree. C.,
a laminating rate of 0.5 m/min and an adhering pressure (cylinder
pressure) of 4.times.10.sup.5 Pa (since a substrate with a
thickness of 3 mm, and a length of 10 cm and a width of 10 cm was
used, a line pressure at this time was 9.8.times.10.sup.3 N/m) to
press the embedding layer whereby the photosensitive resin
composition containing a phosphor and the embedding layer were
embedded in the space surrounded by the barrier rib wall surfaces
and the bottom surface of the substrate.
[0144] Then, an adhesive tape was adhered to the polyethylene film
with a thickness of 100 82 m which is an embedding layer and the
embedding layer was physically peeled off.
[0145] Next, to the surface of the photosensitive element (i) which
is not in contact with the barrier ribs, a photomask for a test is
adhered and an active light was imagewisely irradiated with 500
mJ/cm.sup.2 by using HMW-590 type exposure machine (trade name,
available from ORC Seisakusho) to prepare a photocured pattern
(G).
[0146] Preparation Example 6
[0147] In the same manner as in Preparation example 5 except for
changing the photosensitive element (i) prepared in Preparation
example 2 to the photosensitive element (ii) prepared in
Preparation example 3, a photocured pattern (H) was prepared.
[0148] Preparation Example 7
[0149] In the same manner as in Preparation example 5 except for
changing the photosensitive element (i) prepared in Preparation
example 2 to the photosensitive element (iii) prepared in
Preparation example 4, a photocured pattern (J) was prepared.
Example 1
[0150] The above-mentioned pattern (G) was subjected to spray
development at 30.degree. C. for 70 seconds by using a 1% by weight
sodium carbonate aqueous solution, and then subjected to dipping by
rocking at 30.degree. C. for 10 minutes by using a 1% by weight
malonic acid aqueous solution to prepare a phosphor pattern
precursor (G-1). Then, the phosphor pattern precursor (G-1) was
elevated at a temperature raising rate of 2.degree. C./sec in an
electric furnace and heat treatment (calcination) was carried out
at 450.degree. C. for one hour to obtain a phosphor pattern
(G-1').
[0151] The resulting phosphor pattern (G-1') was scraped away to
make a sample, and the sample (hereinafter merely referred to as
"phosphor pattern (G-1')") was examined as mentioned below (other
samples of Examples and Comparative examples are also examined in
the same manner).
[0152] The contents of an alkali metal or an alkaline earth metal
of the phosphor pattern (G-1') were analyzed by the
atomic-absorption spectroscopy (ICP) and the results are shown in
Table 4.
[0153] Also, the phosphor pattern (G-1' was filled in a concave
portion of a stainless plate having the concave portion (diameter:
2 cm, depth: 1 mm). Next, by using a microfluorometer (available
from Bunko Keiki Co.), chromaticity was measured. Moreover, a color
difference was measured by using an untreated (no operation was
applied) blue phosphor as a standard, and the results are shown in
Table 7. At this time, a wavelength which excites the phosphor
pattern was made 254 nm.
[0154] Comparative Example 1
[0155] In the same manner as in Example 1 except for subjecting to
acid treatment by using a 1% by weight malonic acid aqueous
solution, a phosphor pattern (GG-1') was prepared. The contents of
an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (GG-1') are shown in Table 4. Also, chromaticity
of the phosphor pattern at this time is shown in Table 7. Further,
a color difference was measured by using an untreated blue phosphor
as a standard.
Example 2
[0156] In the same manner as in Example 1 except for replacing a 1%
by weight malonic acid aqueous solution with a 5% by weight
benzyltriethylammonium chloride aqueous solution, a phosphor
pattern (G-2') was prepared. The contents of an alkali metal or an
alkaline earth metal of the resulting phosphor pattern (G-2') are
shown in Table 4. Also, chromaticity of the phosphor pattern at
this time is shown in Table 7. Further, a color difference was
measured by using an untreated blue phosphor as a standard.
Example 3
[0157] In the same manner as in Comparative example 1 except for
replacing a 1% by weight sodium carbonate aqueous solution with a
1% by weight tetramethylammonium hydroxide aqueous solution and
effecting spray development for 15 second, a phosphor pattern
(G-3') was prepared. The contents of an alkali metal or an alkaline
earth metal of the resulting phosphor pattern (G-3') are shown in
Table 4. Also, chromaticity of the phosphor pattern at this time is
shown in Table 7. Further, a color difference was measured by using
an untreated blue phosphor as a standard.
Example 4
[0158] In the same manner as in Example 3 except for replacing a 1%
by weight tetramethylammonium hydroxide aqueous solution with an
emulsion liquor comprising 3-methyl-3-methoxybutyl acetate and
water (20/80 (weight ratio)) and effecting spray development for
100 seconds, a phosphor pattern (G-4') was prepared. The contents
of an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (G-4') are shown in Table 4. Also, chromaticity of
the phosphor pattern at this time is shown in Table 7. Further, a
color difference was measured by using an untreated blue phosphor
as a standard.
Example 5
[0159] The above-mentioned pattern (H) was subjected to spray
development at 30.degree. C. for 70 seconds by using a 1% by weight
sodium carbonate aqueous solution, and then subjected to dipping by
rocking at 30.degree. C. for 10 minutes by using a 1% by weight
malonic acid aqueous solution to prepare a phosphor pattern
precursor (H-1). Then, the phosphor pattern precursor (H-1) was
elevated at a temperature raising rate of 2.degree. C./sec in an
electric furnace and heat treatment (calcination) was carried out
at 450.degree. C. for one hour to obtain a phosphor pattern (H-1').
Then, the phosphor pattern (H-1') was removed from barrier
ribs.
[0160] The contents of an alkali metal or an alkaline earth metal
of the phosphor pattern (H-1') are shown in Table 5.
[0161] Also, the phosphor pattern (H-1') was filled in a concave
portion of a stainless plate having the concave portion (diameter:
2 cm, depth: 1 mm). Next, by using a luminometer (available from
Topkon Co.), emission luminance of the phosphor pattern (H-1') was
measured. In the same manner, emission luminance of an untreated
green phosphor was also measured. At this time, wavelengths which
excite the phosphor pattern were made 147 nm, 172 nm and 254 nm.
Moreover, a relative emission luminance (%) of the phosphor pattern
(H-1') when an emission luminance of the untreated green phosphor
was made 100, and the results are shown in Table 8 (other Examples
and Comparative examples were also measured in the same
manner).
[0162] Comparative Example 2
[0163] In the same manner as in Example 4 except for subjecting to
acid treatment by using a 1% by weight malonic acid aqueous
solution, a phosphor pattern (HH-1') was prepared. The contents of
an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (HH-1') are shown in Table 5. Also, a relative
emission luminance (%) of the phosphor pattern (HH-1') when the
emission luminance of the untreated green phosphor was made 100 was
measured and the results are shown in Table 8.
Example 6
[0164] In the same manner as in Example 5 except for replacing a 1%
by weight malonic acid aqueous solution with a 5% by weight
benzyltriethylammonium chloride aqueous solution, a phosphor
pattern (H-2') was prepared. The contents of an alkali metal or an
alkaline earth metal of the resulting phosphor pattern (H-2') are
shown in Table 5. Also, a relative emission luminance (%) of the
phosphor pattern (H-2') when the emission luminance of the
untreated green phosphor was made 100 was measured and the results
are shown in Table 8.
Example 7
[0165] In the same manner as in Comparative example 2 except for
replacing a 1% by weight sodium carbonate aqueous solution with a
1% by weight tetramethylammonium hydroxide aqueous solution and
effecting spray development for 15 second, a phosphor pattern
(H-3') was prepared. The contents of an alkali metal or an alkaline
earth metal of the resulting phosphor pattern (H-3') are shown in
Table 5. Also, a relative emission luminance (%) of the phosphor
pattern (H-3') when the emission luminance of the untreated green
phosphor was made 100 was measured and the results are shown in
Table 8.
Example 8
[0166] In the same manner as in Example 7 except for replacing a 1%
by weight tetramethylammonium hydroxide aqueous solution with an
emulsion liquor comprising 3-methyl-3-methoxybutyl acetate and
water (20/80 (weight ratio)) and effecting spray development for
100 seconds, a phosphor pattern (H-4') was prepared. The contents
of an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (H-4') are shown in Table 5. Also, a relative
emission luminance (%) of the phosphor pattern (H-4') when the
emission luminance of the untreated green phosphor was made 100 was
measured and the results are shown in Table 8.
Example 9
[0167] The above-mentioned pattern (J) was subjected to spray
development at 30.degree. C. for 70 seconds by using a 1% by weight
sodium carbonate aqueous solution, and then subjected to dipping by
rocking at 30.degree. C. for 10 minutes by using a 1% by weight
malonic acid aqueous solution to prepare a phosphor pattern
precursor (J-1). Then, the phosphor pattern precursor (J-1) was
elevated at a temperature raising rate of 2.degree. C./sec in an
electric furnace and heat treatment (calcination) was carried out
at 450.degree. C. for one hour to obtain a phosphor pattern (J-1').
Then, the phosphor pattern (J-1') was removed from barrier
ribs.
[0168] The contents of an alkali metal or an alkaline earth metal
of the phosphor pattern (J-1') are shown in Table 6.
[0169] Also, emission luminance of the phosphor pattern (J-1') and
that of the untreated red phosphor were measured and a relative
emission luminance (%) of the phosphor pattern (J-1') when an
emission luminance of the untreated red phosphor was made 100 was
obtained, and the results are shown in Table 9.
Comparative Example 3
[0170] In the same manner as in Example 9 except for subjecting to
acid treatment by using a 1% by weight malonic acid aqueous
solution, a phosphor pattern (JJ-1') was prepared. The contents of
an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (JJ-1') are shown in Table 6. Also, a relative
emission luminance (%) of the phosphor pattern (JJ-1') when the
emission luminance of the untreated red phosphor was made 100 was
measured and the results are shown in Table 9.
Example 10
[0171] In the same manner as in Example 9 except for replacing a 1%
by weight malonic acid aqueous solution with a 5% by weight
benzyltriethylammonium chloride aqueous solution, a phosphor
pattern (J-2') was prepared. The contents of an alkali metal or an
alkaline earth metal of the resulting phosphor pattern (J-2') are
shown in Table 6. Also, a relative emission luminance (%) of the
phosphor pattern (J-2') when the emission luminance of the
untreated red phosphor was made 100 was measured and the results
are shown in Table 9.
Example 11
[0172] In the same manner as in Comparative example 3 except for
replacing a 1% by weight sodium carbonate aqueous solution with a
1% by weight tetramethylammonium hydroxide aqueous solution and
effecting spray development for 15 second, a phosphor pattern
(J-3') was prepared. The contents of an alkali metal or an alkaline
earth metal of the resulting phosphor pattern (J-3') are shown in
Table 6. Also, a relative emission luminance (%) of the phosphor
pattern (J-3') when the emission luminance of the untreated red
phosphor was made 100 was measured and the results are shown in
Table 9.
Example 12
[0173] In the same manner as in Example 7 except for replacing a 1%
by weight tetramethylammonium hydroxide aqueous solution with an
emulsion liquor comprising 3-methyl-3-methoxybutyl acetate and
water (20/80 (weight ratio)) and effecting spray development for
100 seconds, a phosphor pattern (J-4') was prepared. The contents
of an alkali metal or an alkaline earth metal of the resulting
phosphor pattern (J-4') are shown in Table 6. Also, a relative
emission luminance (%) of the phosphor pattern (J-4') when the
emission luminance of the untreated red phosphor was made 100 was
measured and the results are shown in Table 9.
5 TABLE 4 Sodium Sodium content (% by Phosphor content (mg) weight)
Standard Blue 0.001 0.0001 phosphor Example 1 G-1' 0.8 0.08 Example
2 G-2' 0.2 0.02 Example 3 G-3' 0.1 0.01 Example 4 G-4' 0.1 0.01
Comparative GG-1' 97 9.7 example 1
[0174]
6 TABLE 5 Sodium Sodium content (% by Phosphor content (mg) weight)
Standard Green 0.009 0.0009 phosphor Example 5 H-1' 0.4 0.04
Example 6 H-2' 0.3 0.03 Example 7 H-3' 0.15 0.015 Example 8 H-4'
0.1 0.01 Comparative HH-1' 95 9.5 example 2
[0175]
7 TABLE 6 Sodium Sodium content (% by Phosphor content (mg) weight)
Standard Red 0.001 0.0001 phosphor Example 9 J-1' 0.2 0.02 Example
10 J-2' 0.1 0.01 Example 11 J-3' 0.1 0.01 Example 12 J-4' 0.1 0.01
Comparative JJ-1' 86 8.6 example 3
[0176]
8 TABLE 7 Chromaticity Color dif- Phosphor (CIE regulation) ference
pattern x y (.DELTA.E) Standard 1 G' 0.147 0.058 standard Example 1
G-1' 0.145 0.059 0.003 Example 2 G-2' 0.145 0.057 0.003 Example 3
G-3' 0.147 0.059 0.002 Example 4 G-4' 0.145 0.060 0.005 Comparative
GG-1' 0.150 0.069 0.024 example 1
[0177]
9 TABLE 8 Relative emission luminance (%) Excited Excited Excited
Phosphor at 147 nm at 172 nm at 254 nm Standard Green 100 100 100
phosphor Example 5 H-1' 94 92 90 Example 6 H-2' 94 92 91 Example 7
H-3' 94 92 94 Example 8 H-4' 99 100 100 Comparative HH-1' 84 89 77
example 2
[0178]
10 TABLE 9 Relative emission luminance (%) Excited Excited Excited
Phosphor at 147 nm at 172 nm at 254 nm Standard Red 100 100 100
phosphor Example 9 J-1' 98 100 99 Example 10 J-2' 100 100 99
Example 11 J-3' 99 99 100 Example 12 J-4' 100 98 99 Comparative
JJ-1' 84 81 80 example 3
[0179] In Table 4, any alkali metal or alkaline earth metal other
than sodium was detected.
[0180] From the results shown in Table 4 and Table 7, it can be
understood that in Comparative example 1, the content of sodium in
the phosphor pattern (the content of sodium contained in 1 g of the
phosphor) exceeds 20 mg, chromaticity was markedly changed (it was
shown the value which exceeds the color difference of 0.010 or
more). On the other hand, in Examples 1 to 4, when the content of
sodium in the phosphor pattern (the content of sodium contained in
1 g of the phosphor) was made 20 mg or less, chromaticity of the
phosphor after calcination was not changed.
[0181] From the results shown in Table 5 and Table 8, it can be
understood that in Examples 5 to 8, the contents of sodium in the
phosphor pattern (the content of sodium contained in 1 g of the
phosphor) were made 20 mg or less, emission luminances of the
phosphors after calcination were not lowered as compared with the
results of the standard 2. However, in Comparative example 2, when
the content of sodium in the phosphor pattern (the content of
sodium contained in 1 g of the phosphor) exceeds 20 mg, emission
luminance of the phosphor after calcination was lowered (10% or
more based on the standard).
[0182] From the results shown in Table 6 and Table 9, it can be
understood that in Examples 9 to 12, the contents of sodium in the
phosphor pattern (the content of sodium contained in 1 g of the
phosphor) were made 20 mg or less, emission luminances of the
phosphors after calcination were not lowered as compared with the
results of the standard 3. However, in Comparative example 3, when
the content of sodium in the phosphor pattern (the content of
sodium contained in 1 g of the phosphor) exceeds 20 mg, emission
luminance of the phosphor after calcination was lowered (10% or
more based on the standard).
[0183] According to the process for preparing the phosphor pattern
of the present invention, a phosphor pattern with less change in
emission characteristics can be produced with good yield.
[0184] According to the organic alkali developer or the emulsion
developer for forming a phosphor pattern of the present invention,
a phosphor pattern with less change in emission characteristics can
be produced with good yield.
[0185] The phosphor pattern of the present invention has less
change in emission characteristics.
[0186] The back plate for a plasma display panel of the present
invention is provided with a phosphor pattern which is less change
in emmision characteristics.
* * * * *