U.S. patent application number 13/644642 was filed with the patent office on 2013-10-17 for organic electroluminescent element sealing composition and organic light-emitting device.
The applicant listed for this patent is Koji OKAWA, Osamu TAMURA. Invention is credited to Koji OKAWA, Osamu TAMURA.
Application Number | 20130270993 13/644642 |
Document ID | / |
Family ID | 46233480 |
Filed Date | 2013-10-17 |
United States Patent
Application |
20130270993 |
Kind Code |
A1 |
OKAWA; Koji ; et
al. |
October 17, 2013 |
ORGANIC ELECTROLUMINESCENT ELEMENT SEALING COMPOSITION AND ORGANIC
LIGHT-EMITTING DEVICE
Abstract
This organic electroluminescent element sealing composition
contains an addition reaction curing type silicone composition
which is liquid at normal temperature and has a curing temperature
of 100 degrees C. or below and a moisture content of 400 ppm or
less. The addition reaction curing type silicone composition
contains (A) polyorganosiloxane having an average of 0.2 to 5
alkenyl groups bonded to silicon atoms in one molecule, (B)
polyorganohydrogensiloxane having at least two or more hydrogen
atoms bonded to silicon atoms in one molecule, and (C) a
platinum-based catalyst. The organic electroluminescent element
sealing composition can prevent deterioration of the organic
electroluminescent element and can provide the organic
light-emitting device having a good light-emitting property for a
long period.
Inventors: |
OKAWA; Koji; (Tokyo, JP)
; TAMURA; Osamu; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
OKAWA; Koji
TAMURA; Osamu |
Tokyo
Tokyo |
|
JP
JP |
|
|
Family ID: |
46233480 |
Appl. No.: |
13/644642 |
Filed: |
October 4, 2012 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12971404 |
Dec 17, 2010 |
8304991 |
|
|
13644642 |
|
|
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|
Current U.S.
Class: |
313/504 ;
525/478 |
Current CPC
Class: |
C08G 77/12 20130101;
H05B 33/04 20130101; C08G 77/20 20130101; H01L 51/5246 20130101;
H01L 51/5253 20130101; C08L 83/04 20130101 |
Class at
Publication: |
313/504 ;
525/478 |
International
Class: |
H05B 33/04 20060101
H05B033/04 |
Claims
1. A sealing composition, comprising an addition reaction curing
type silicone composition in liquid form at normal temperature, the
addition reaction curing type silicone composition having a curing
temperature of 100.degree. C. or below and a moisture content of
400 ppm or less, the addition reaction curing type silicone
composition comprising: (A) polyorganosiloxane having an average of
0.5 or more alkenyl group bonded to silicon atom in one molecule;
(B) polyorganohydrogensiloxane having 2 or more hydrogen atoms
bonded to silicon atoms in one molecule; and (C) a platinum-based
catalyst.
2. The sealing composition according to claim 1, wherein the
polyorganohydrogensiloxane comprises 0.2 to 5.0 times of the
hydrogen atoms bonded to the silicon atoms as many as alkenyl group
of the polyorganosiloxane.
3. An organic light-emitting device, comprising: a first substrate;
an organic electroluminescent element disposed on a surface of the
first substrate; a second substrate disposed on the surface of the
first substrate to face the organic electroluminescent element; and
a sealing layer filled between the first substrate and the second
substrate to seal the organic electroluminescent element, the
sealing layer being made of a cured material of the sealing
composition according to claim 1.
4. The organic light-emitting device according to claim 3, further
comprising a barrier layer configured to block oxygen and moisture
between the sealing layer and the organic electroluminescent
element.
5. An addition reaction curing type silicone composition in liquid
form at normal temperature, comprising: (A) polyorganosiloxane
having an average of 0.5 or more alkenyl group bonded to silicon
atom in one molecule; (B) polyorganohydrogensiloxane having 2 or
more hydrogen atoms bonded to silicon atoms in one molecule; and
(C) a platinum-based catalyst, wherein the addition reaction curing
type silicone has a curing temperature of 100.degree. C. or below
and a moisture content of 400 ppm or less.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation of U.S. application Ser.
No. 12/971,404, filed Dec. 17, 2010, the entire contents of which
are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] An organic EL (electroluminescent) element is a
self-light-emission type electroluminescent element having a
structure that an organic light-emitting medium layer is held
between two electrode layers at least one of which has translucency
and causes the organic light-emitting medium layer to emit light by
applying a voltage between the electrodes. This organic EL element
has advantages such as a wide viewing angle, a fast response speed
and low power consumption, and therefore it is expected as a flat
panel display used instead of a cathode-ray tube and a liquid
crystal display.
[0003] But, the light-emitting medium layer of the organic EL
element is composed of an organic material, and it is apt to be
degraded by an influence of moisture, oxygen or heat in the
atmosphere. Since this degradation lowers the light emitting
performance of the organic EL element, display characteristics tend
to be degraded. To prevent the organic EL element from
deteriorating, there is adopted a structure that the top surface of
the organic EL element formed on a glass substrate is covered by a
glass substrate (glass cover) to form a hollow inner structure, and
an adsorbing desiccant for moisture and the like is disposed within
the hollow portion. And, there is also proposed a structure that
the entire organic EL element is sealed with epoxy resin having low
moisture permeability which is filled into the hollow portion
between two glass substrates (see, for example, JP-A 2006-28386
(KOKAI)).
[0004] But, the structure that the adsorbing desiccant is disposed
in the hollow portion cannot suppress sufficiently the organic EL
element from degrading because the water-absorbing capacity of the
desiccant is insufficient. The method of sealing with the epoxy
resin filled into the hollow portion has problems that the organic
EL element has a possibility of deterioration because the moisture
contained in the epoxy resin is not controlled sufficiently and the
organic EL element is deteriorated by heat applied at the time of
curing because the epoxy resin has a high curing temperature.
[0005] The present invention has been achieved to solve the
above-described problems, and the invention provides an organic
electroluminescent element sealing composition capable of
preventing deterioration of an organic electroluminescent element
and an organic light-emitting device having a good light-emitting
property for a long period.
SUMMARY OF THE INVENTION
[0006] According to an aspect of the present invention, there is
provided an organic electroluminescent element sealing composition
for sealing an organic electroluminescent element, which comprises
an addition reaction curing type silicone composition which is
liquid at normal temperature and has a curing temperature of 100
degrees C. or below and a moisture content of 400 ppm or less.
[0007] The organic light-emitting device of the present invention
is provided with a first substrate; an organic electroluminescent
element formed on the first substrate; a second substrate arranged
to face the organic electroluminescent element formed surface of
the first substrate; and a sealing layer filled between the first
substrate and the second substrate to seal the organic
electroluminescent element, wherein the sealing layer is a cured
material of the organic electroluminescent element sealing
composition of the present invention.
[0008] According to the organic electroluminescent element sealing
composition, an addition reaction curing type silicone composition
capable of curing at a low temperature of 100 degrees C. or below
is used, and a moisture content (ratio) in the composition is
prepared low to 400 ppm or less, so that deterioration of the
organic electroluminescent element due to moisture contained in the
sealing material itself and deterioration of the organic
electroluminescent element due to heating for curing the sealing
layer can be prevented. Therefore, the use of the sealing
composition can provide formation of an excellent sealing layer
without causing peeling and free from occurrence of a crack due to
a temperature change, and can provide an organic electroluminescent
element having an excellent light-emitting property free from
defective light emission for a long period.
BRIEF DESCRIPTION OF THE DRAEING
[0009] FIG. 1 is a sectional view showing an example of an organic
EL device for which the sealing composition of the present
invention is used as a sealing material.
DETAILED DESCRIPTION OF THE INVENTION
[0010] Modes of conducting the present invention will be described
below with reference to the drawing, which is provided for
illustration only, and the present invention is not limited to the
drawing.
[0011] The organic electroluminescent element sealing composition
according to an embodiment of the present invention is comprises of
an addition reaction curing type silicone composition which is
liquid at normal temperature and has a moisture content (rate) of
400 ppm or below and a curing temperature of 100 degrees C. or
below. This addition reaction curing type silicone composition
contains (A) polyorganosiloxane having an average of 0.5 or more
alkenyl group bonded to silicon atoms in one molecule, (B)
polyorganohydrogensiloxane having 2 or more hydrogen atoms bonded
to silicon atoms in one molecule, and (C) a platinum-based
catalyst. The organic electroluminescent element sealing
composition and the organic light-emitting device according to the
embodiment are described below in detail.
[Component (A)]
[0012] Component (A) is a base polymer of an addition reaction
curing type silicone composition and has an average of 0.5 or more
alkenyl group bonded to silicon atom in one molecule in order to
cure sufficiently the composition. It has an average of 0.6 or more
alkenyl group preferably in one molecule, and more preferably an
average of 2 or more alkenyl groups.
[0013] Examples of the silicon atom-bonded alkenyl group include a
vinyl group, an allyl group, a butenyl group, a petenyl group and a
hexenyl group, and the vinyl group is preferable. The alkenyl group
may be bonded to the silicon atom at the molecular chain end, the
silicon atom intermediate at the molecular chain or both of them.
But from a view point of the curing rate of the composition to be
obtained and the physical properties after curing, it is preferable
that the alkenyl group is bonded to at least the silicon atoms at
the molecular chain end, and particularly to the silicon atom at
both terminal ends of the molecular chain.
[0014] Examples of the silicon atom-bonded organic group other than
the alkenyl group of the component (A) include those having 1 to 12
carbon atoms, and preferably 1 to 8 carbon atoms, which are an
alkyl group such as a methyl group, an ethyl group, a propyl group,
etc.; a cycloalkyl group such as a cyclopentyl group, a cyclohexyl
group, etc.; an aryl group such as a phenyl group, a tolyl group, a
xylyl group, etc.; or a halogenated hydrocarbon group or the like
having the above hydrogen atoms substituted partly by chlorine
atoms, fluorine atoms or the like. The silicon atom-bonded organic
group is preferably an alkyl group or an aryl group, and more
preferably a methyl group or a phenyl group.
[0015] The component (A) is not limited to having a particular
molecular structure but has, for example, a linear, cyclic,
branched or another structure. The linear structure is preferable
from a view point of mechanical strength or the like of the cured
material. And, as the component (A), one of them can be used alone,
or two or more of them can also be used in combination.
[0016] The viscosity of the component (A) at 23 degrees C. is 10 to
1,000,000 mPas, and preferably 100 to 1,000,000 mPas. When it is
less than 10 mPas, the mechanical strength after curing tends to
decrease. Meanwhile, when it exceeds 1,000,000 mPas, workability of
the composition tends to become low.
[Component (B)]
[0017] Polyorganohydrogensiloxane of component (B) is a
cross-linking agent of the component (A) and has two or more, and
preferably three or more hydrogen atoms (SiH groups) bonded to
silicon atoms in one molecule. This SiH group may be at the ends of
the molecular chain, intermediate the molecular chain or both.
[0018] For example, the component (B) is expressed by an average
composition formula RsH.sub.tSiO.sub.[4-(s+t)]/2 . . . (1). In the
formula (1), R is the same or different substituted or
non-substituted univalent hydrocarbon group not having an aliphatic
unsaturated bond. Examples of R include an alkyl group such as a
methyl group, an ethyl group, a propyl group, an isopropyl group, a
butyl group, an isobutyl group, a tert-butyl group, a hexyl group,
a cyclohexyl group or an octyl group; an aryl group such as a
phenyl group or a tolyl group; an aralkyl group such as a benzyl
group or a phenylethyl group; and a group which has part or all of
the hydrogen atoms in the above groups substituted by a halogen
atom such as a fluorine, chlorine or bromine atom, or a cyano
group, and its examples include groups having 1 to 12 carbon atoms,
such as a chloromethyl group, a bromoethyl group, a trifluoropropyl
group and a cyanoethyl group. Among them, the alkyl group having 1
to 4 carbon atoms, such as a methyl group, an ethyl group, a propyl
group, an isopropyl group, a butyl group or an isobutyl group, is
preferable, and the methyl group is more preferable from viewpoints
of easiness of synthesis and cost.
[0019] In the formula (1), s and t are positive numbers satisfying
0.5.ltoreq.s.ltoreq.2.2, 0.ltoreq.t.ltoreq.2 and
0.5.ltoreq.s+t.ltoreq.3, and preferably positive numbers satisfying
0.6.ltoreq.s.ltoreq.2.0, 0.01.ltoreq.t.ltoreq.1.8 and
0.6.ltoreq.s+t.ltoreq.2.8.
[0020] The molecular structure of the component (B) may be any of a
linear, branched, cyclic or three-dimensional network structure.
The viscosity of the component (B) is 5,000 mPas or less, and
preferably 1 to 1,000 mPas, at 23 degrees C.
[0021] Examples of the component (B) include
1,1,3,3-tetramethyl-1,3-dihydrogensiloxane, methylhydrogen cyclic
polysiloxane, methylhydrogensiloxane-dimethylsiloxane cyclic
copolymers, both end trimethylsiloxy-blocked
methylhydrogenpolysiloxane, both end trimethylsiloxy-blocked
dimethylsiloxane-methylhydrogenpolysiloxane copolymers, both end
dimethylhydrogensiloxy-blocked dimethylsiloxane, both end
dimethylhydrogensiloxy-blocked
dimethylsiloxane-methylhydrogensiloxane copolymer, both end
trimethylsiloxy-blocked methylhydrogensiloxane-diphenylsiloxane
copolymers, both end trimethylsiloxy-blocked
methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer,
both end dimethylhydrogensiloxy-blocked
methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer,
a copolymer of (CH.sub.3).sub.2HSiO.sub.1/2 unit and SiO.sub.4/2
unit, a copolymer of (CH.sub.3).sub.2HSiO.sub.1/2 unit, SiO.sub.4/2
unit and (C.sub.6H.sub.5)SiO.sub.3/2 unit, and the like.
[0022] The blending amount of the component (B) is an amount that
hydrogen atoms (SiH group) bonded to the silicon atoms of the
component (B) relative to one alkenyl group of the component (A)
become 0.2 to 5.0, and preferably 0.5 to 3.0. When the SiH group of
the component (B) is less than 0.2, sufficient cross-linking cannot
be obtained. When it exceeds 5.0, an unreacted SiH group remains,
and the physical properties of the cured material tend to become
instable.
[Component (C)]
[0023] As a platinum-based catalyst which is component (C), the
known platinum-based catalyst used for the hydrosilylation reaction
can be used. Its examples include platinum black, platinum
chloride, chloroplatinic acid, a reactant of chloroplatinic acid
and monohydric alcohol, a complex of chloroplatinic acid and
olefins or vinylsiloxane, platinum bisacetoacetate and the
like.
[0024] The blending amount of the component (C) can be adjusted
appropriately depending on the desired curing rate or the like. It
is normally 0.1 to 1,000 ppm, and preferably 0.5 to 500 ppm, in
terms of a platinum element relative to the total amount of the
composition.
[Other Optional Components]
[0025] An addition reaction curing type silicone composition which
is a sealing composition of the embodiment and in a liquid state at
normal temperature has the above-described components (A) to (C) as
the basic components, and if necessary, a filler, a reaction
inhibitor, a flame retardance-imparting agent, a heat resistance
improving agent, an adhesion-imparting agent, a thixotropy
imparting agent, a pigment, a plasticizer, etc. may be added as
optional components in a range not impairing the object of the
invention.
[0026] Examples of the filler include silica, titanium oxide and
the like. A blending amount of the filler is adequate when it is in
a range that the workability is kept fine and the properties of the
cured material are not impaired, and it is preferably 1 to 50 parts
by weight relative to 100 parts by weight of the component (A).
[0027] Examples of the reaction inhibitor include acetylene alcohol
such as 3,5-dimethyl-1-hexyn-3-ol, 2-methyl-3-hexyn-2-ol or
1-ethynyl-1-cyclohexanol, 3-methyl-3-pentene-1-yne,
3,5-dimethyl-3-hexene-1-yne or the like, or a methylvinylsiloxane
cyclic compound, an organic nitrogen compound, an organic
phosphorus compound or the like. A blending amount of the reaction
inhibitor is adequate when it is in a range that curing reactivity
and preservation stability are kept good, and the properties of the
cured material are not impaired, and it is preferably 0.001 to 1
part by weight relative to 100 parts by weight of the component
(A).
[Sealing Composition and its Production Method]
[0028] To produce the sealing composition of the embodiment,
polyorganohydrogensiloxane which is the component (B)
(cross-linking agent) and other optional components are added to
the alkenyl group-containing polyorganosiloxane which is the
component (A), the platinum-based catalyst (C) is further added,
and they are kneaded by a known kneader at normal temperature or
while heating (e.g., 80 to 200 degrees C.), if necessary. As the
kneader, a known device provided with a heating means and a cooling
means can be used. For example, a planetary mixer, a triple roll, a
Shinagawa mixer, a Tri-mix, a Twin-mix and the like can be used
alone or in combination.
[0029] The sealing composition of the embodiment obtained as
described above has a curing temperature of normal temperature
(normally 23 degrees C.) or higher and 100 degrees C. or below.
And, a moisture content (rate) in the composition is adjusted to
fall in a range of 400 ppm or less. When the curing temperature of
the composition is lower than normal temperature, workability
becomes poor because curing takes long time. When the curing
temperature exceeds 100 degrees C., the organic electroluminescent
element is easily degraded by heat when curing by heating, and it
is highly probable that an effective pixel area of the organic
light-emitting device is reduced. In addition, it is not desirable
when the moisture content (rate) exceeds 400 ppm because it becomes
highly possible that the organic electroluminescent element is
deteriorated with water produced from the composition that is used
as the sealing material.
[0030] To adjust the moisture content of the composition to the
above-described range, there can be adopted a method of heating at
least one of the component (A) and the component (B) while
controlling the temperature and time prior to blending and
kneading. It is especially preferable to adopt a method of heating
the component (A) under reduced pressure. In other words, it is
preferable that the moisture content in the composition is adjusted
to 400 ppm or less by evaporating/volatilizing the moisture in the
component (A), by heating the component (A) with the pressure
reduced, if necessary. And, if the moisture content in the
composition finally obtained can be suppressed to 400 ppm or less,
it is also possible to add water to the composition to be obtained
after kneading the component (A) undergone the heating treatment
with the other components.
[0031] It is also preferable that the sealing composition of the
embodiment has a viscosity of 10 to 1,000,000 mPas at 23 degrees
C.
[Cured Material of Sealing Composition]
[0032] The sealing composition of the embodiment according to the
invention is cured by heating at a temperature of 100 degrees C. or
below for 5 to 120 minutes (e.g., at 80 degrees C. for 60 minutes).
Since the sealing composition cures in the allowable temperature
range (100 degrees C. or below) of the organic electroluminescent
element (organic EL element), it can be used suitably as the
sealing material for sealing the organic EL element. For the
composition forming and curing methods, curing conditions and the
like, known methods and conditions can be applied.
[Organic Light-Emitting Device]
[0033] The organic EL device for which the sealing composition of
the embodiment is used as the sealing material has a structure as
shown in for example FIG. 1 that a first electrode (anode) layer 2,
an organic EL element comprising the organic EL layer 3 as an
organic light-emitting medium and a second electrode (cathode)
layer 4 are formed on a first substrate 1 of glass or the like, and
a second substrate 5 such as a glass cover is disposed to face the
organic EL element. And, as a sealing layer, a cured material layer
6 of the sealing composition of the embodiment is filled and formed
within the second substrate 5 (between the second substrate 5 and
the organic EL element).
[0034] In the organic EL device, a barrier layer (protective layer)
for blocking oxygen and moisture can be disposed between the cured
material layer 6 of the sealing composition and the organic EL
element. The material forming the barrier layer is silicon nitride,
silicon oxide, silicon oxynitride or the like. As a method of
forming the barrier layer, there is used a resistance heating
deposition method, an electron beam deposition method, a reactive
deposition method, an ion plating method, a sputtering method, a
CVD method or the like.
EXAMPLES
[0035] While the present invention is described with reference to
specific examples, it is to be understood that the invention is not
limited to the described examples. (Examples 1 to 3 and Comparative
Examples 1 and 2)
[0036] First, (A) 100 parts by weight of polydimethylsiloxane which
had a viscosity of 3000 mPas at 23 degrees C. and had both terminal
ends of the molecular chain blocked by a dimethylvinyl siloxy group
were thermally treated under reduced pressure of 10 mmHg at a
temperature of 150 degrees C. for two hours. Then, the 100 parts by
weight of the polydimethylsiloxane undergone the thermal treatment
were added with (B) 1.5 parts by weight (a molar ratio (H/Vi ratio)
of hydrogen groups in the component (B) and vinyl groups in the
component (A) is 1.5) of polymethylhydrogensiloxane having hydrogen
groups (about 20 hydrogen groups in one molecule) at a ratio of 50
mold at side chains and (C) 10 ppm (platinum amount) of a
vinylsiloxane complex compound of chloroplatinic acid, and 0.05
part by weight of 1-ethynyl-1-cyclohexanol, and they were kneaded
homogeneously at room temperature. Thus, the silicone compositions
of Example 1 and Example 2 were obtained.
[0037] In Example 3 and Comparative Example 2, water was added to
the silicone composition obtained in Example 1 to increase a
moisture content. And, the component (A) was not thermally treated
in Comparative Example 1, but the component (A) in normal storage
was used as it was to obtain the silicone composition.
[0038] Subsequently, the silicone compositions of Examples 1 to 3
and Comparative Examples 1 and 2 were measured for moisture
contents by a Karl Fischer moisture measuring apparatus (Model
KF-06 of Mitsubishi Kasei Corporation). The measured results are
shown together with curing temperatures described later in Table
1.
[0039] The silicone compositions obtained in Examples 1 to 3 and
Comparative Examples 1 and 2 were used to seal the organic EL
elements. First, an organic EL element was produced. Specifically,
a pattern of an ITO film (thickness of 150 nm) which was a first
electrode layer was formed on a glass substrate by sputtering. A
mixture (thickness of 20 nm) of poly(3,4-ethylenedioxythiophene)
and polystyrene sulfonate was spin-coated as a hole-transporting
layer,
poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene](MEHPPV)
(thickness of 100 nm) was spin-coated as a light-emitting layer,
and unnecessary portions were removed from the hole-transporting
layer by methanol and from the light-emitting layer by toluene to
form a pattern of the organic light-emitting medium layer. Then, a
Ca film (thickness of 5 nm) and an Al film (thickness of 150 nm)
were laminated as a second electrode layer by a vapor deposition
method. In addition, a silicon nitride film (500 nm) was formed as
a barrier layer (protective layer) by a plasma CVD method.
[0040] Subsequently, the silicone compositions obtained in Examples
1 to 3 and Comparative Examples 1 and 2 were coated on the obtained
individual organic EL elements, and a glass cover was applied to
them. The coated layers of the silicone compositions of Examples 1
and 3 and Comparative Examples 1 and 2 were cured by heating to 80
degrees C. The coated layer of the silicone composition of Example
2 was cured by heating to 100 degrees C. The produced organic EL
panels were examined for the effective pixel area of the organic EL
element. And, a long-term storage test was performed at 85 degrees
C. for 500 hours to examine the effective pixel area after the
long-term test. The measured results are shown in Table 1.
Comparative Example 3
[0041] The organic EL element was sealed in the same manner as in
Example 1 except that an epoxy resin (EH1600-G2 of Inabata &
Co., Ltd.) was used instead of the silicone composition. The used
epoxy resin was measured for a moisture content (rate) to find that
it was 100 ppm as shown in Table 1. The sealing layer was formed by
curing the epoxy resin by heating it to 120 degrees C. Then, the
produced organic EL panel was measured for the effective pixel area
of the organic EL element. The effective pixel area after the
long-term test (500-hour storage at 85 degrees C.) was also
examined. The measured results are shown in Table 1.
TABLE-US-00001 TABLE 1 Example Example Example Comp. Comp. Comp. 1
2 3 Ex. 1 Ex. 2 Ex. 3 Component (A) Polydimethylsiloxane with
viscosity 100 100 100 100 100 of 3000 mPa s (23.degree. C.) having
a vinyl group at both terminal ends Component (B)
Polymethylhydrogensiloxane having 1.5 1.5 1.5 1.5 1.5 50 mol % of
hydrogen groups at side chains Component (C) Vinylsiloxane complex
compound of (10 ppm) (10 ppm) (10 ppm) (10 ppm) (10 ppm)
chloroplatinic acid (platinum amount) Other optional components
1-ethynyl-1-cyclohexanol 0.05 0.05 0.05 0.05 0.05 Epoxy resin 100
H/Vi 1.5 1.5 1.5 1.5 1.5 Water amount (ppm) 50 50 400 800 5000 100
Curing temperature (.degree. C.) 80 100 80 80 80 120 Effective
pixel area (%) of organic EL Early stage 100 100 100 100 70 50
After long-term test (85.degree. C. .times. 500 hrs) 100 99 99 70
20 30 Comp. Ex. = Comparative Example
[0042] It is seen from Table 1 that the organic EL panels having
the sealing layers formed by using the silicone compositions
obtained in Examples 1 to 3 did not have a reduction in the
effective pixel area of the organic EL element after the long-term
test. On the other hand, the organic EL panels having the sealing
layers formed by using the silicone compositions obtained in
Comparative Example 1 and Comparative Example 2 had a reduction in
the effective pixel area due to the moisture contained in the
compositions after the long-term test. And, the organic EL panel
having the sealing layer formed of the silicone composition of
Comparative Example 2 had a reduction in the effective pixel area
even at an early stage before the long-term test. In addition, the
organic EL panels having the sealing layer, which was formed by
using the epoxy resin of Comparative Example 3, had the effective
pixel area of the organic EL element considerably degraded due to
heating at the time of forming the sealing layer, and some of them
had cracks partly and the effective pixel area was further reduced
when the long-term test was completed.
* * * * *