JP6915527B2 - Transparent desiccant for organic EL and how to use it - Google Patents

Description

The present invention relates to a desiccant for organic EL (electronic luminescence) and a method of using the desiccant.

The organic electronics luminescence (hereinafter abbreviated as organic EL) panel has low power consumption and is thin because the element itself emits light as it is called a self-luminous type and does not require a separate light source like the backlight of a liquid crystal panel. It has features such as easy weight reduction and weight reduction, and is said to have higher image quality than liquid crystal panels. However, there is a problem that the element is damaged even if a very small amount of water enters the panel (generation of dark spots).

Since the organic EL panel requires a structure that highly prevents the intrusion of moisture, a structure in which the organic EL element is sealed with a transparent substrate made of glass or the like is generally used. This structure is a hollow sealing structure in which an organic EL element having a structure in which an anode, an organic layer, and a cathode are laminated on a substrate such as glass is formed, and facing digging-type glass or the like is combined to dry the inside. It is obtained by filling with nitrogen gas or the like and adhering the ends with a sealing material. At this time, various studies have been reported, such as a method of installing a desiccant inside or a method of covering an organic EL element with a filler for the purpose of removing water that has entered the organic EL panel. In either method, when the desiccant or the filler has translucency, so-called top emission, in which the light generated by the organic EL element is taken out from the upper surface, becomes possible, which is more effective. ..

Further, although the organic EL element is mainly formed by a process such as thin film deposition, the presence of minute particles may cause a so-called short-circuit phenomenon in which the cathode and the anode are short-circuited. When the short-circuit phenomenon occurs, it is necessary to separate the elements around the particles that cause the short circuit with a laser or the like, which causes problems such as partial loss of light emission and increase in the process.

Patent Document 1 discloses that an organic EL panel is filled with silicone oil so as to cover the organic EL element, and an organometallic compound or a polymer thereof is applied to the silicone oil as a water replenishing component. .. According to this method, the organic EL element is covered with silicone oil, and the water replenishing effect can be obtained by containing the rehydrating component in the silicone oil, and the short-circuit phenomenon suppressing effect can be obtained by insulating the vicinity of the particles. ..

However, in Patent Document 1, since the silicone oil is filled so as to cover the organic EL element, it is necessary to dispense the silicone oil in an appropriate amount, and there is a problem that the state after bonding is difficult to be the same. Further, in order to have the translucency required for the top emission type, the content of the water replenishing component must be lowered, and there is a problem that it is difficult to obtain a sufficient effect of suppressing dark spots.

Further, Patent Document 2 discloses that a mixture of a group 2 or group 3 or group 4 metal alkoxide and a transparent polymer inert to the metal alkoxide is used as a transparent desiccant. In this method, it is difficult to maintain the initial translucency because the reaction between the metal alkoxide and the water causes a phenomenon in which the translucency is gradually impaired as the moisture absorption progresses. Further, it is difficult to obtain the effect of suppressing the short-circuit phenomenon by the above method.

Further, Patent Document 3 discloses that a metal hydride is mixed in a silicone rubber as a desiccant and placed in an organic EL structure. This method does not require a method of filling in an organic EL panel and the process is easy, but it is difficult to obtain translucency of silicone rubber containing a desiccant, and it is impossible to form a top emission type. be.

Japanese Unexamined Patent Publication No. 2013-176751 Japanese Unexamined Patent Publication No. 2009-095824 Japanese Unexamined Patent Publication No. 2001-057287

The present invention has been made in view of the above circumstances, and is an organic EL capable of top emission, highly transparent, having a small shrinkage amount for a long period of time even under high temperature and high humidity, and suppressing element damage (generation of dark spots). It is an object of the present invention to provide a transparent desiccant for use and a method of using the same.

As a result of diligent studies to achieve the above object, the present inventors can achieve top emission by using a cured product of an organopolysiloxane composition having a specific composition as a transparent desiccant for organic EL. Therefore, it has been found that the amount of shrinkage can be reduced for a long period of time even under high temperature and high humidity with high transparency and the occurrence of dark spots can be suppressed, and the present invention has been made.

Therefore, the present invention provides the following transparent desiccant for organic EL and a method of using the same.
1. 1. The following (A) to (C) components (A) The following (A-1) and (A-2)
(A-1) Resin-like organopolysiloxane having at least two alkenyl groups in one molecule: 1 to 100% by mass
(A-2) Linear organopolysiloxane having at least two alkenyl groups in one molecule: 0 to 99% by mass
(However, the total amount of (A-1) and (A-2) is 100% by mass)
Organopolysiloxane containing an alkenyl group consisting of: 100 parts by mass,
(B) The following average formula (1)
H _a R _b SiO _{(4-ab) / 2} (1)
(In the formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, a is 0.001 to 1.0, and b is 0.7 to 2.1).
Organohydrogenpolysiloxane having a hydrogen atom bonded to at least two silicon atoms in one molecule represented by (A): Silicon in the component (B) with respect to 1 mol of the silicon atom-bonded alkenyl group in the component (A). Weight corresponding to 1.0 to 20 mol of hydrogen atom bonded to an atom, and (C) hydrosilylation catalyst: 0.5 to 1,000 ppm as a platinum group metal (mass equivalent) with respect to 100 parts by mass of component (A).
Cured der organopolysiloxane composition comprising is, and the cured product to 1mm thick sheet, JIS K 7361-1: by a method according to 1997 when measured for total light transmittance, the total light A transparent desiccant for organic EL characterized by having a transmittance of 90% or more. 2. The transparent desiccant for organic EL according to 1, wherein the linear organopolysiloxane of the component (A-2) is used in combination of two or more kinds having different weight average molecular weights.
3. 3. A method for using a transparent desiccant for organic EL, which comprises placing and using the transparent desiccant for organic EL according to 1 or 2 above in an organic EL panel.
4. The method for using the transparent desiccant for organic EL according to 3, wherein the transparent desiccant is in the form of a sheet having a thickness of 15 μm to 2 mm.
5. The method for using the transparent desiccant for organic EL according to 3 or 4, wherein the desiccant is placed only above the organic EL element in the method for using the transparent desiccant for organic EL.
6. The method for using the transparent desiccant for organic EL according to 3 or 4, wherein the desiccant is not in contact with the organic EL element in the method for using the transparent desiccant for organic EL.

The transparent desiccant for organic EL of the present invention is highly transparent, has a small shrinkage amount for a long period of time even under high temperature and high humidity, and can suppress damage (generation of dark spots) of the organic EL element. Further, since the transparent desiccant for organic EL of the present invention is highly transparent, it can be applied to a top emission type that transmits light emitted from an organic EL element.
Further, the transparent desiccant for organic EL and the method of using the transparent desiccant for organic EL of the present invention are not a method of filling the organic EL panel without gaps, but a step of applying a preformed transparent desiccant to the organic EL element in a non-contact manner. Is easy.
Further, in the transparent desiccant of the present invention and the method of using the transparent desiccant, although the transparent desiccant is not in contact with the organic EL element, the small molecule siloxane in the desiccant is diffused and deposited in the organic EL panel, and the organic EL element is used. It is possible to obtain the effect of insulating the vicinity of the small particles existing at the time of formation and suppressing the so-called short-circuit phenomenon in which the cathode and the anode are short-circuited via the particles.

It is a schematic diagram for demonstrating the method of attaching the transparent desiccant for organic EL which is one Embodiment of this invention in an organic EL panel. It is the schematic which shows the organic EL panel obtained by the method of FIG. It is the schematic which shows the organic EL panel manufactured without dropping the organopolysiloxane composition in the panel.

Hereinafter, the present invention will be described in more detail.
The transparent desiccant for organic EL of the present invention comprises the following components (A) to (C) (A) and the following (A-1) and (A-2).
(A-1) Resin-like organopolysiloxane having at least two alkenyl groups in one molecule: 1 to 100% by mass
(A-2) Linear organopolysiloxane having at least two alkenyl groups in one molecule: 0 to 99% by mass
(However, the total amount of (A-1) and (A-2) is 100% by mass)
Organopolysiloxane containing an alkenyl group consisting of: 100 parts by mass,
(B) The following average formula (1)
H _a R _b SiO _{(4-ab) / 2} (1)
(In the formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, a is 0.001 to 1.0, and b is 0.7 to 2.1).
Organohydrogenpolysiloxane having a hydrogen atom bonded to at least two silicon atoms in one molecule represented by (A): Silicon in the component (B) with respect to 1 mol of the silicon atom-bonded alkenyl group in the component (A). Weight corresponding to 1.0 to 20 mol of hydrogen atom bonded to an atom, and (C) hydrosilylation catalyst: 0.5 to 1,000 ppm as a platinum group metal (mass equivalent) with respect to 100 parts by mass of component (A).
It is a cured product of an organopolysiloxane composition containing. Hereinafter, each component will be described in detail.

(A) Alkenyl Group-Containing Organopolysiloxane The alkenyl group-containing organopolysiloxane of the component (A) in the present invention is the main agent of the organopolysiloxane composition. The component (A) is a resin-like organopolysiloxane having at least two alkenyl groups in one molecule (A-1) and a linear chain having at least two alkenyl groups in one molecule (A-2). It is characterized by being composed of an organopolysiloxane.

The component (A-1) is a resin-like organopolysiloxane having at least 2 alkenyl groups, preferably 2 to 8 alkenyl groups in one molecule, and specifically, the following formula (2).
(R ¹ ₃ SiO _1/2 ) _p (R ¹ ₂ SiO _2/2 ) _q (R ¹ SiO _3/2 ) _r (SiO _4/2 ) _s (2)
It is an organopolysiloxane represented by.

In the above formula (2), R ¹ is a monovalent hydrocarbon group independently selected from an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 12 carbon atoms, and an alkenyl group having 2 to 10 carbon atoms. .. Specific examples of the monovalent hydrocarbon group include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group and cyclohexyl group, vinyl group, allyl group, butenyl group, pentenyl group and hexenyl group. Examples thereof include an alkenyl group such as a group and a cyclohexenyl group, and an aryl group such as a phenyl group. As R ¹ , a methyl group or a phenyl group is preferable, but it is necessary that the molecule contains two or more alkenyl groups. A vinyl group is preferable as the alkenyl group.

Further, in the above formula (2), p is 0 <p ≦ 0.7, preferably 0.3 <p <0.7, and q is 0 ≦ q ≦ 0.2, preferably 0 ≦ q. ≤0.1, r is 0≤r≤0.2, preferably 0≤r≤0.1, and s is 0 <s≤0.7, preferably 0.3 <s <0. It is a number of .7 and p + q + r + s = 1.

The component (A-1) may be used alone or in combination of two or more.

The component (A-2) is a linear organopolysiloxane having at least 2 alkenyl groups, preferably 2 to 8 alkenyl groups in one molecule, and specifically, the following formula (3).
(R ¹ ₃ SiO _1/2 ) ₂ (R ¹ ₂ SiO _2/2 ) _x (3)
It is an organopolysiloxane represented by.

In the above formula (3), R ¹ can exemplify the same group as above, and preferably has an alkenyl group only at the terminal. x is an integer of 100 to 50,000, preferably an integer of 150 to 20,000.

Specific examples of the linear organopolysiloxane of the component (A-2) include a trimethylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer at both ends of the molecular chain, and a trimethylsiloxy group-blocked methylvinylpolysiloxane at both ends of the molecular chain. Dimethylsiloxane / methylvinylsiloxane / methylphenylsiloxane copolymer at both ends of the molecular chain, dimethylpolysiloxane at both ends of the molecular chain, dimethylvinylsiloxy group at both ends of the molecular chain, methylvinylpolysiloxane, molecule Both ends of the chain dimethylvinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer, both ends of the molecular chain dimethylvinylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane / methylphenylsiloxane copolymer, both ends of the molecular chain divinylmethylsiloxy group-blocked Didimethylpolysiloxane, divinylmethylsiloxy group-blocked dimethylsiloxane / methylvinylsiloxane copolymer at both ends of the molecular chain, trivinylsiloxy group-blocked dimethylpolysiloxane at both ends of the molecular chain, trivinylsiloxy group-blocked dimethylsiloxane / methylvinyl at both ends of the molecular chain Examples thereof include a siloxane copolymer and a mixture of two or more of these organopolysiloxanes.

The component (A-2) may be used alone or in combination of two or more. When two types of linear organopolysiloxane as the component (A-2) are used in combination, the weight average molecular weight of the organopolysiloxane on the low molecular weight side is preferably 1,000 to 50,000, more preferably 1,000 to 50,000. It is 1,500 to 20,000. On the other hand, the weight average molecular weight of the organopolysiloxane on the high molecular weight side is preferably more than 1,500 to 200,000, more preferably more than 2,000 to 100,000. However, it is assumed that (weight average molecular weight on the low molecule side) <(weight average molecular weight on the polymer side).
The weight average molecular weight in the present invention can be determined as a polystyrene-equivalent weight average molecular weight in GPC (gel permeation chromatography) analysis using THF measured under the following conditions as a developing solvent.

[Measurement condition]
Developing solvent: tetrahydrofuran (THF)
Flow rate: 0.6 mL / min
Detector: Differential Refractometer (RI)
Column: TSK Guardcolum SuperH-L
TSKgel SuperH4000 (6.0mm ID x 15cm x 1)
TSKgel SuperH3000 (6.0mm ID x 15cm x 1)
TSKgel SuperH2000 (6.0 mm ID x 15 cm x 2)
(Both made by Tosoh)
Column temperature: 40 ° C
Sample preparation conditions: Dissolve 1 part by mass of a 50% xylene solution of organopolysiloxane resin in 1,000 parts by mass of THF and filter with a membrane filter. Sample injection amount: 10 μL

The blending ratio of the component (A-1) and the component (A-2) is such that the total of the components (A-1) and (A-2) is 100% by mass, and the component (A-1) is used. Is 1 to 100% by mass, preferably 10 to 90% by mass, and the component (A-2) is 0 to 99% by mass, preferably 10 to 90% by mass. If it deviates from the above compounding ratio, the effect of suppressing the light emission shrinkage of the organic EL panel of the obtained cured silicone product may not be sufficiently obtained under high temperature and high humidity and for a long period of time.

(B) Organohydrogenpolysiloxane The organohydrogenpolysiloxane of the component (B) in the present invention plays the role of a cross-linking agent that forms a cross-linked structure by hydrosilylation with the above-mentioned alkenyl group-containing organopolysiloxane.

This organohydrogenpolysiloxane has the following average formula (1).
H _a R _b SiO _{(4-ab) / 2} (1)
It is an organohydrogenpolysiloxane having a hydrogen atom bonded to at least two silicon atoms in one molecule represented by.

In the above formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, preferably 1 to 8, a is 0.001 to 1.0, preferably 0.01 to 1.0, and b is. It is 0.7 to 2.1, preferably 0.8 to 2.0.

Specific examples of R in the above formula include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group and cyclohexyl group, and aryl groups such as phenyl group. Among these, a methyl group, an ethyl group and a phenyl group are preferable, and a methyl group and an ethyl group are particularly preferable.

Specific examples of the organohydrogenpolysiloxane of the component (B) include 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethylcyclotetrasiloxane, and tris (hydrogen). Dimethylsiloxy) methylsilane, tris (hydrogendimethylsiloxy) phenylsilane, methylhydrogencyclopolysiloxane, methylhydrogensiloxane / dimethylsiloxane cyclic copolymer, trimethylsiloxy group-blocked methylhydrogenpolysiloxane at both ends of the molecular chain, molecular chain Double-ended trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane / methylhydrogensiloxane / methylphenylsiloxane copolymer, molecular chain double-ended trimethylsiloxy group-blocked dimethylsiloxane -Methylhydrogensiloxane-Diphenylsiloxane copolymer, dimethylhydrogensiloxy group-blocked at both ends of the molecular chain, methylhydrogenpolysiloxane, dimethylhydrogensiloxy group-blocked at both ends of the molecular chain, dimethylpolysiloxane, dimethylhydrogensiloxy at both ends of the molecular chain Base-blocking dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain double-ended dimethylhydrogensiloxy group-blocking dimethylsiloxane / methylphenylsiloxane copolymer, molecular chain double-ended dimethylhydrogensiloxy group-blocking dimethylsiloxane / diphenylsiloxane co-weight In coalescing, dimethylhydrogensyloxy group-blocking methylphenylpolysiloxane at both ends of the molecular chain, dimethylhydrogensiloxy group-blocking diphenylpolysiloxane at both ends of the molecular chain, and in each of these exemplary compounds, some or all of the methyl groups are ethyl groups. Substituted with another alkyl group such as propyl group, formula: _{siloxane unit represented by R 3} SiO _1/2 and formula: siloxane unit represented by R ₂ HSiO _1/2 and formula: represented by SiO _4/2 organosiloxane copolymers consisting of siloxane units of the formula: siloxane units represented by the formula R ₂ HSiO _1/2: organosiloxane copolymers composed of siloxane units represented by SiO _4/2, wherein: RHSiO _2/2 Organoshi consisting of a siloxane unit represented by and a siloxane unit represented by the formula: RSiO _3/2 or a siloxane unit represented by the formula: HSiO _3/2. Examples thereof include a losane copolymer and a mixture of two or more of these organopolysiloxanes.

The blending amount of the component (B) is a mass corresponding to 1 to 20 mol of hydrogen atoms bonded to the silicon atom in the component (B) with respect to 1 mol of the silicon atom-bonded alkenyl group in the component (A). It is preferably a mass corresponding to 1 to 10 mol, and more preferably a mass corresponding to 1 to 5 mol.

(C) Hydrosilylation catalyst In the hydrosilylation catalyst of the component (C) in the present invention, the alkenyl group-containing organopolysiloxane of the component (A) and the organohydrogenpolysiloxane of the component (B) are crosslinked by a hydrosilylation reaction. It acts as a catalyst for the process, and is an essential component for the rapid progress of the cross-linking reaction.

The catalyst for the hydrosilylation reaction is preferably a platinum group metal-based catalyst, and specifically, platinum black, second platinum chloride, platinum chloride acid, a reaction product of platinum chloride acid and a monovalent alcohol, platinum chloride acid and olefins. Examples thereof include a platinum group metal catalyst such as a complex of platinum chloride acid and a vinyl group-containing (poly) siloxane, a platinum-acetylacetone complex, and a platinum-cyclopentadienyl complex.

The blending amount of the component (C) is usually 0.5 to 1,000 ppm, preferably 1 to 500 ppm, based on 100 parts by mass of the component (A) as a simple substance (mass equivalent). If the amount is less than the above-mentioned numerical range, the curability is lowered, and if it is more than the above-mentioned range, the cost becomes high and it becomes uneconomical.

Other Ingredients The organopolysiloxane composition, which is a material for the transparent desiccant for organic EL of the present invention, has other components (A) to (C) as long as the effects of the present invention are not impaired. Ingredients may be added. Specifically, at least one functionality selected from a reaction control agent for a hydrosilylation reaction, an adhesive-imparting material (particularly, an alkenyl group, an epoxy group, an amino group, a (meth) acryloxy group, a mercapto group, etc. in the molecule). Examples thereof include an organic silicon compound such as a functional alkoxysilane which contains a group and does not contain a SiH group in the molecule), a thixophilic imparting material, and the like.

The organopolysiloxane composition can be prepared by uniformly mixing the above components using a commonly used mixing stirrer such as a kneader or a planetary mixer, a kneader or the like.

Method for Producing Transparent Drying Agent for Organic EL The transparent desiccant for organic EL of the present invention is a cured product of the above-mentioned organopolysiloxane composition. As a molding method for this organopolysiloxane composition, a known molding method can be appropriately selected according to the shape and size of the target molded product. For example, molding methods such as injection molding, compression molding, injection molding, calendar molding, extrusion molding, coating, and screen printing are exemplified. The curing conditions may be known conditions in the molding method to be adopted, and generally, the temperature conditions are 60 to 450 ° C., preferably 80 to 400 ° C., more preferably 120 to 200 ° C. for several seconds to 1 day. Molding time. Further, for the purpose of reducing the small molecule siloxane component remaining in the cured product, the temperature is 150 to 250 ° C., preferably 200 to 240 ° C. for 1 hour or longer, preferably 1 to 70 hours. More preferably, post-curing (secondary vulcanization) may be performed for about 1 to 10 hours.

Further, the organopolysiloxane composition can be used as a sheet by a conventional method such as screen printing, a calendar molding method, an injection method or a pressing method, in addition to a coating method such as a dispensing method or an injection method. In this case, the silicone rubber sheet obtained by forming the organopolysiloxane composition into a sheet is preferably molded with a thickness of 15 μm to 2 mm, more preferably 20 μm to 1 mm. If this thickness is thinner than 15 μm, it is difficult to form a uniform film thickness, which is not preferable, and if it is thicker than 2 mm, the total thickness of the organic EL device increases, which is inappropriate.

The transparent desiccant thus obtained is highly transparent and can be easily thinned, and is therefore suitable as a transparent desiccant for organic EL. Specifically, it is preferable to use a cured product sheet having a thickness of 1 mm and having a total light transmittance of 90% or more measured by a method according to JIS K 7361-1: 1997. If the total light transmittance of the cured product sheet is less than 90%, it may be disadvantageous to use this transparent desiccant for an organic EL module.

Method of using transparent desiccant for organic EL As described above, the organopolysiloxane composition is preferably used as a silicone rubber sheet having a thickness of 15 μm to 2 mm after curing, and is particularly used in an organic EL panel. Is useful. Usually, an organic EL panel has a hollow sealing structure in which an organic EL element having a structure in which an anode, an organic layer, and a cathode are laminated on a substrate such as glass is formed, and facing digging-type glass or the like is combined. .. As an example of using the transparent desiccant of the present invention, the digging-type glass is attached by dropping a predetermined amount of the organopolysiloxane composition inside the fold-in of the digging-type glass and curing the composition. In the organic EL panel produced together, the transparent desiccant of the present invention can be placed only above the organic EL element, and the desiccant is not in contact with the organic EL element. That is, the above-mentioned method of using the transparent desiccant for organic EL is not a method of filling the organic EL panel without gaps, but a preformed transparent desiccant is applied to the organic EL element in a non-contact manner, so that the process is easy. Is. Further, in the method of using the transparent desiccant, although the transparent desiccant is not in contact with the organic EL element, the small molecule siloxane in the desiccant is diffused and deposited in the organic EL panel and exists at the time of forming the organic EL element. It is possible to obtain the effect of insulating the vicinity of the small particles and suppressing the so-called short-circuit phenomenon in which the cathode and the anode are short-circuited via the particles.

Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In addition, in the unit of the compounding amount, a part indicates a mass part. Me represents a methyl group and Vi represents a vinyl group.

[Preparation Example 1]
[ Preparation of Organopolysiloxane Composition 1 ]
As a component (A-1), a resin-like organopoly having 6.8 mol% of _{Me 2} ViSiO _1/2 unit, 39.8 mol% of Me ₃ SiO _1/2 unit, and 53.4 mol% of SiO _{4/2 unit.} Resin-like organopolysiloxane (weight average molecular weight 5,000) having 49.0 parts of siloxane (weight average molecular weight 6,000: composition a) _{, 50 mol% of Me 2} ViSiO _1/2 unit, and 50 mol% of MeSiO _{3/2 unit.} : Composition b) 1.0 part of dimethylpolysiloxane (weight average molecular weight 1,000: composition c) 15 in which _{both ends are sealed with Me 2} ViSiO _1/2 units as the component (A-2). 35 parts of dimethylpolysiloxane (weight average molecular weight 5,000: composition d) having both ends _{sealed in Me 2} ViSiO _1/2 units was used, and the following average formula was used as the component (B).
H _1.29 Me _0.72 SiO _{1.98 / 2}
5.1 parts of organohydrogenpolysiloxane represented by (A) [amount of (B) component silicon atom-bonded hydrogen atom 2.0 mol relative to 1 mol of silicon atom-bonded vinyl group of component (A)], (C) 0.1 part of 1,1-divinyltetramethyldisiloxane complex solution of chloroplatinic acid (1% by mass as platinum alone) as an ingredient, 0.03 part of 1-ethynyl-1-cyclohexanol as a hydrosilylation reaction control agent These components were kneaded with a planetary mixer (PLMG-350, Inoue Seisakusho) for 10 minutes to obtain "organopolysiloxane composition 1".

[ Method for manufacturing organic EL panel ]
A method for manufacturing an organic EL panel in which the transparent desiccant of the present invention is mounted in an organic EL panel will be described with reference to FIGS. 1 (A) to 1 (E). This manufacturing method comprises an anode electrode (102), a hole injection layer (103), a hole transport layer (104), and a light emitting layer (105) on a non-alkali glass (101) having a thickness of 1 mm and a size of 50 mm × 50 mm. , The electron transport layer (106), the electron injection layer (107), and the cathode electrode (108) are laminated to form an organic EL element laminated glass body (109) (see FIG. 1 (A)).

_{Next, in a box having an N 2} atmosphere in which the water content was controlled to 10 ppm or less, a concave digging-shaped non-alkali sealed mold having a thickness of 1 mm and a size of 42 mm × 42 mm shown in FIG. The organopolysiloxane composition (111) was added dropwise to a portion having a size of 38 mm × 38 mm inside the digging of the glass (110). Then, the mixture was left on a flat plate for about 30 minutes to flatten the dropped organopolysiloxane composition, and then placed and heated on a heater plate at 110 ° C. for 30 minutes to cure the organopolysiloxane composition. (State shown in FIG. 1 (C)).

Next, as shown in FIG. 1 (D), the ultraviolet curable epoxy resin (112) is dispensed on the end portion of the non-alkali sealed glass (110) having a width of 2 mm in the same box, and then the above organic. The EL element laminated glass body (109) was bonded in the direction in which the organic layer was arranged inside the glass. After that, using a metal halide lamp (HANDY UV-100 manufactured by ORC), ultraviolet irradiation was performed so that the integrated irradiation amount was 10,000 mJ / cm ^{2 at an ultraviolet intensity of 10 mW / cm 2} , and the epoxy resin was adhered to each other. The organic EL panel (113) shown in E) was obtained.

[Example 1]
(Preparation of composition)
The composition a in the component (A-1) shown in Preparation Example 1 is 0.98 parts, the composition b is 0.02 parts, the composition c in the component (A-2) is 29 parts, and the composition d. 70 parts, that is, (A-1) :( A-2) = 1:99 (mass%), and then the components (B) and (C) are the same as in Preparation Example 1 above. As described above, the composition was prepared and kneaded to obtain the organopolysiloxane composition of Example 1.

(Arranged in the organic EL panel)
The organopolysiloxane composition of Example 1 was placed in the organic EL panel by the procedure shown in the above method for producing an organic EL panel. The amount dropped in the organic EL panel was 0.14 g (amount equivalent to 100 μm thickness).

Hereinafter, the compounding ratio (% by mass) of (A-1): (A-2) was changed to prepare an organopolysiloxane composition of each example other than Example 1, and an organic EL panel was prepared in the same procedure. It was placed inside. The compounding ratio (mass%) of (A-1): (A-2) is shown below in [Examples 2 to 4] and [Comparative Examples 1 and 2]. In each example, the dropping amount in the organic EL panel was 0.14 g (amount equivalent to 100 μm thickness).

[Example 2]
The composition a in the component (A-1) shown in Preparation Example 1 is 9.8 parts, the composition b is 0.2 parts, the composition c in the component (A-2) is 26 parts, and the composition d. Was prepared to be 64 parts, that is, (A-1) :( A-2) = 10:90 (mass%). The components (B) and (C) were prepared in the same manner as in Preparation Example 1 above.

[Example 3]
49 parts of the composition a in the component (A-1) shown in Preparation Example 1, 1.0 part of the composition b, 15 parts of the composition c in the component (A-2), and 35 parts of the composition d. Part, that is, (A-1) :( A-2) = 50:50 (mass%) was prepared. The components (B) and (C) were prepared in the same manner as in Preparation Example 1 above.

[Example 4]
98 parts of the composition a in the component (A-1) shown in Preparation Example 1, 2 parts of the composition b, the composition c in the component (A-2), and the composition d are not added, that is, ( A-1): (A-2) = 100: 0 (mass%). The components (B) and (C) were prepared in the same manner as in Preparation Example 1 above.

[Comparative Example 1]
The composition a in the component (A-1) shown in Preparation Example 1 is 0.49 parts, the composition b is 0.01 part, and the composition c in the component (A-2) is 29.2 parts. The product d was prepared so as to have 70.3 parts, that is, (A-1) :( A-2) = 0.5: 99.5 (mass%). The components (B) and (C) were prepared in the same manner as in Preparation Example 1 above.

[Comparative Example 2]
The composition a and composition b in the component (A-1) shown in Preparation Example 1 were not added, and the composition c in the component (A-2) was 29.5 parts and the composition d was 70. .5 parts, that is, (A-1) :( A-2) = 0: 100 (mass%) was prepared. The components (B) and (C) were prepared in the same manner as in Preparation Example 1 above.

[Example 5]
Next, 49 parts of the composition a in the component (A-1) shown in Preparation Example 1 above, 1.0 part of the composition b, 15 parts of the composition c in the component (A-2), and the composition. d was prepared in 35 parts, that is, (A-1) :( A-2) = 50: 50 (mass%), and then 1 hydrogen atom bonded to the silicon atom in the component (B) was added. 2.7 parts of organohydrogenpolysiloxane as the component (B) was added so as to have a concentration of 0.0 mol. The component (C) was prepared as described in Preparation Example 1 above.

[Comparative Example 3]
Next, the component (A) is the same as in Example 5, and the component (B) is an organohydrogenpoly so that the hydrogen atom bonded to the silicon atom in the component corresponds to 0.5 mol. 1.3 parts of siloxane was added. The component (C) was prepared as described in Preparation Example 1 above.

(Adjustment of the amount added in the organic EL panel)
Examples 6 to 8 and Comparative Example 4 below are examples in which the amount of the organopolysiloxane composition added into the organic EL panel is adjusted, and are as follows.

[Example 6]
The components (A), (B) and (C) are the same as in Example 3, and the same organopolysiloxane composition as in Example 3 is dropped into the organic EL panel by the procedure shown in the above method for producing an organic EL panel. did. The dropping amount was 1.4 g (amount equivalent to 1 mm thickness).

[Example 7]
The components (A), (B) and (C) are the same as in Example 3, and the same organopolysiloxane composition as in Example 3 is dropped into the organic EL panel by the procedure shown in the above method for producing an organic EL panel. did. The dropping amount was 0.07 g (amount equivalent to 50 μm thickness).

[Example 8]
The components (A), (B) and (C) are the same as in Example 3, and the same organopolysiloxane composition as in Example 3 is dropped into the organic EL panel by the procedure shown in the above method for producing an organic EL panel. did. The dropping amount was 0.02 g (amount equivalent to a thickness of 15 μm).

[Comparative Example 4]
Next, the components (A), (B) and (C) were the same as in Example 3, and calcium oxide particles (particle size 0.1 μm) were added to the obtained organopolysiloxane composition as a desiccant. 10% by mass was added based on the total amount of the siloxane composition. Then, this calcium oxide particle mixture is kneaded with a planetary mixer (PLMG-350, Inoue Seisakusho) for 30 minutes, and 0.14 g (equivalent to 100 μm thickness) is placed in the organic EL panel by the procedure shown in the above organic EL panel manufacturing method. Dropped.

[Comparative Example 5]
A sample in which the organopolysiloxane composition was not dropped into the organic EL panel was prepared by the procedure shown in the above method for producing an organic EL panel. The inside of this organic EL panel was filled with dry nitrogen. The obtained organic EL panel (114) without dropping of organopolysiloxane is shown in FIG.

The durability, transparency, and short-circuit defect occurrence of the organic EL panels and sheet-shaped organopolysiloxane cured products of Examples 1 to 8 and Comparative Examples 1 to 5 were evaluated by the following methods. The results are shown in Table 1.

〔durability〕
^{The obtained organic EL panel was driven to emit light at a current density of 10 mA / cm 2} under an atmosphere of normal room temperature (25 ° C.), and dark spots were observed using an optical microscope (LV150N manufactured by Nikon).
Further, the organic EL panel is put into a high-temperature and high-humidity test tank controlled at 60 ° C. × 90% RH, taken out to the atmosphere at normal room temperature (25 ° C.) every 200 hours, and similarly, a current of ^{10 mA / cm 2 is obtained.} It was driven by light emission at a density, and changes in the size and number of dark spots were confirmed with the above optical microscope. Exposure in a high temperature and high humidity test tank was carried out for up to 1,000 hours.
Targeting dark spots with a diameter of 5 μm or more, “A: particularly excellent” when the ratio of the dark spots to the total light emitting area is less than 3%, and “B: excellent” when the ratio is 3% or more and less than 5%. ".", And the case of 5% or more was evaluated as "C: inferior."

〔transparency〕
For measuring the transmittance, 1.4 g (equivalent to 1 mm thickness) of the organopolysiloxane composition to be evaluated is placed inside an acrylic plate dug (38 mm × 38 mm) having the same shape as the above-mentioned non-alkali sealed glass (110). After dropping, the mixture was left on a flat plate for about 30 minutes to flatten the dropped organopolysiloxane composition. Then, it was placed and heated on a heater plate at 110 ° C. for 30 minutes to cure the organopolysiloxane composition, and then peeled off from the acrylic plate. The transmittance of the cured product sheet having a size of 38 mm × 38 mm and a thickness of 1 mm obtained by this method was measured by an ultraviolet-visible infrared spectrophotometer (V-780DS manufactured by JASCO Corporation).

[Presence / absence of short circuit defect]
Five samples of each of the above-mentioned organic EL panels were prepared, and in the same manner as above, an exposure test was conducted in a high-temperature and high-humidity tank controlled at 60 ° C. × 90% RH for 1,000 hours, and the atmosphere was at room temperature (25 ° C.). After taking it out below, it was confirmed whether or not a short circuit occurred in the organic EL panel. To check if a short circuit occurs, ^{check the presence or absence of light emission by applying a current of 10 mA / cm 2} or more. If no light emission is observed, check the presence or absence of a short circuit mark on the cathode. If there is a short circuit mark, the laser When the light emission was reproduced by separating the elements in the vicinity of the short mark, the sample was identified as a short defect occurrence sample. The results are shown in Table 1. The notation in Table 1 indicates the number of samples with short-circuit defects for the total number of 5 samples [number of short-circuit defective samples / total number of samples (5)].

As a result of performing the above evaluation method, the following can be considered.
In Examples 1 to 4, it can be seen that the higher the ratio of (A-1) in the blending ratio of (A-1): (A-2), the higher the effect of suppressing dark spots. Further, in Example 1, when (A-1) :( A-2) = 1: 99 (mass%), it was extremely good up to 400 hours in the 60 ° C. × 90% RH test, and then a slight dark spot was observed. Although an increase is seen, it remains at less than 5% even at 1,000 hours, which is good.
In Comparative Examples 1 and 2, (A-1): (A-2) = 0.5: 99.5 (mass%) and (A-1) :( A-2) = 0: 100 (mass%). In each case, the dark spot reaches 5% or more in 200 hours in the 60 ° C. × 90% RH test, resulting in insufficient durability.
Comparing Example 5 and Comparative Example 3, as shown in Comparative Example 3, the molar ratio of the hydrogen atom bonded to the silicon atom in the component (B) to 1 mol of the silicon atom-bonded alkenyl group in the component (A). That is, when the (B) / (A) molar ratio is 0.5, the durability is insufficient in the 60 ° C. × 90% RH test.
Comparative Example 4 is an example in which calcium oxide particles (particle size 0.1 μm) were added in an amount of 10% by mass with respect to the total amount of the organopolysiloxane composition, and as a result, the particles were relatively maintained in durability but were produced. The transmittance is impaired due to the mixture.
Comparative Example 5 has a structure in which only dry nitrogen is filled in the organic EL panel, and as a result, the durability is extremely insufficient, and short-circuit defects occur in 3 out of 5 samples. Was seen, and the result was not sufficient for practical use.

101 Alkali-free glass 102 Anode electrode 103 Hole injection layer 104 Hole transport layer 105 Light emitting layer 106 Electron transport layer 107 Electron injection layer 108 Cathode electrode 109 Organic EL element Laminated glass body 110 Alkali-free sealed glass 111 Organopolysiloxane 112 Ultraviolet curable epoxy resin 113 Organic EL panel 114 Organic EL panel (organopolysiloxane composition without dropping)

Claims (6)

The following (A) to (C) components (A) The following (A-1) and (A-2)
(A-1) Resin-like organopolysiloxane having at least two alkenyl groups in one molecule: 1 to 100% by mass
(A-2) Linear organopolysiloxane having at least two alkenyl groups in one molecule: 0 to 99% by mass
(However, the total amount of (A-1) and (A-2) is 100% by mass)
Organopolysiloxane containing an alkenyl group consisting of: 100 parts by mass,
(B) The following average formula (1)
H _a R _b SiO _{(4-ab) / 2} (1)
(In the formula, R is a monovalent hydrocarbon group having 1 to 10 carbon atoms, a is 0.001 to 1.0, and b is 0.7 to 2.1).
Organohydrogenpolysiloxane having a hydrogen atom bonded to at least two silicon atoms in one molecule represented by (A): Silicon in the component (B) with respect to 1 mol of the silicon atom-bonded alkenyl group in the component (A). Weight corresponding to 1.0 to 20 mol of hydrogen atom bonded to an atom, and (C) hydrosilylation catalyst: 0.5 to 1,000 ppm as a platinum group metal (mass equivalent) with respect to 100 parts by mass of component (A).
Cured der organopolysiloxane composition comprising is, and the cured product to 1mm thick sheet, JIS K 7361-1: by a method according to 1997 when measured for total light transmittance, the total light A transparent desiccant for organic EL characterized by having a transmittance of 90% or more. The transparent desiccant for organic EL according to claim 1, wherein the linear organopolysiloxane of the component (A-2) is used in combination of two or more kinds having different weight average molecular weights. A method for using a transparent desiccant for organic EL, which comprises placing and using the transparent desiccant for organic EL according to claim 1 or 2 in an organic EL panel. The method for using the transparent desiccant for organic EL according to claim 3, wherein the transparent desiccant is in the form of a sheet having a thickness of 15 μm to 2 mm. The method for using the transparent desiccant for organic EL according to claim 3 or 4, wherein the desiccant is placed only above the organic EL element in the method for using the transparent desiccant for organic EL. The method for using the transparent desiccant for organic EL according to claim 3 or 4, wherein the desiccant is not in contact with the organic EL element in the method for using the transparent desiccant for organic EL.

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