JP5797443B2 - Curable composition for sealing material and sealing material obtained therefrom - Google Patents

Description

  The present invention relates to a curable composition for a sealing material excellent in moldability for forming a crosslinked rubber having excellent hygroscopicity and gas barrier properties, and a sealing material obtained therefrom. More specifically, it contains an isobutylene polymer having more than one alkenyl group in one molecule, a compound having at least two hydrosilyl groups in one molecule, a hydrosilylation catalyst, and a hygroscopic agent as essential components. The present invention relates to a curable composition for a polyisobutylene-based sealing material, which is capable of efficiently forming a crosslinked rubber having excellent hygroscopicity and gas barrier properties, and a sealing material obtained therefrom. Since the polyisobutylene-based sealing material obtained from the curable composition for sealing materials of the present invention has hygroscopicity and gas barrier properties, it is used in various fields such as electric / electronic, automobile, energy and medical treatment. It can be used in a wide range of applications that require hygroscopicity, gas barrier properties, impact relaxation properties, and the like.

  Electronic devices such as batteries, capacitors (capacitors), and display elements are continually becoming smaller and lighter. These electronic components are always sealed using a resin-based adhesive such as a rubber-based sealing material or a U V curable resin in the sealing process of the exterior portion. However, in these sealing methods, the performance of the electronic component is deteriorated by moisture passing through the sealing material during storage or use. That is, there is a possibility that the electronic components inside the electronic device may be deteriorated or corroded by moisture that has entered the electronic device. For example, in a battery or capacitor using an organic electrolyte, if moisture is mixed in the electrolyte, the electrical conductivity changes, electrolysis of intruded moisture, etc., and the outer case distortion due to voltage drop or gas generation between terminals May cause leakage. As described above, it is difficult to maintain the performance stability and reliability of the electronic device due to moisture that has entered the electronic device.

For example, in an organic EL device, durability that can withstand long-term light emission is required, but one of the causes of deterioration of the light emission characteristics of the organic EL element is the generation of dark spots, and the surface of the component parts of the organic EL element. An organic light emitting layer having at least a light emitting layer composed of a transparent electrode and an organic compound and a back electrode are sequentially laminated with moisture adhering to the water, moisture (humidity) that has penetrated into the organic EL element, and oxygen. It is known to occur by entering into the formed laminate from defects on the surface of the back electrode and causing a divergence between the organic light emitting layer and the back electrode.
On the other hand, in the process of assembling these electronic devices, it is virtually impossible to maintain the humidity at 0 throughout the entire process. For example, during the aging process after completion of the electronic device, the electronic device penetrates into the electronic device during the assembly process. It is essential to absorb the moisture. However, as described above, a technique for reliably and easily absorbing moisture that has entered the electronic device has not yet been established.

  As described above, in the technology for moisture inside the electronic device and moisture from the outside, for example, when an organic EL device is taken as an example, a desiccant is disposed in a sealed internal space as shown in Patent Document 1. When the moisture content of the desiccant is high, the amount of water vapor inside the seal cannot be reduced sufficiently, and the organic light-emitting layer reacts with the residual moisture, causing deterioration of the organic EL element or darkness. There is a problem that causes the generation of spots. In addition, since the organic light emitting layer is exposed at a portion where the organic light emitting layer is not sufficiently covered with the back electrode formed on the upper surface because foreign matter or the like exists in the organic light emitting layer forming region, dark spots due to moisture are exposed in a shorter period of time. There are problems that can occur.

  Further, in a method in which a shield layer such as a resin layer or a glass plate as shown in Patent Documents 2 to 4 is provided via an adhesive or the like, for example, electron injection of the organic EL element due to the stress of the layer laminated on the organic EL element There is a problem that peeling of the layer-organic layer interface or the like and destruction of the element itself occur, and there are significant restrictions on the protective layer to be laminated.

JP 2001-35659 A Japanese Patent Laid-Open No. 4-267097 JP-A-5-36475 JP-A-5-182759

  To provide a curable composition for a sealing material excellent in hygroscopicity, gas barrier properties and impact resistance, which is suitable for sealing electronic devices such as display elements such as organic EL, batteries, capacitors (capacitors) and the like.

  As a result of various studies, the present inventor has found that (A) an isobutylene polymer containing at least one hydrosilylation-capable alkenyl group in the molecule, and (B) at least two hydrosilyl groups in the molecule. (C) Hydrosilylation catalyst, (D) Hygroscopicity, gas barrier property, by crosslinking a curable composition for sealant having fluidity at room temperature, which contains moisture absorption as an essential component. The present invention was completed by obtaining a sealing material excellent in impact resistance.

That is, the present invention
(I). A curable composition for a sealing material containing the following components (A) to (D) and having fluidity at room temperature,
(A) Isobutylene polymer containing at least one alkenyl group capable of hydrosilylation reaction in the molecule (B) Compound containing at least two hydrosilyl groups in the molecule (C) Hydrosilylation catalyst (D) Hygroscopic agent (II). The component (D) is calcium oxide (CaO), barium oxide (BaO), magnesium oxide (MgO), strontium oxide (SrO), phosphorus pentoxide (P ₄ O ₁₀ ), lithium sulfate (Li ₂ SO ₄ ), Sodium sulfate (Na ₂ SO ₄ ), calcium sulfate (CaSO ₄ ), magnesium sulfate (MgSO ₄ ), cobalt sulfate (CoSO ₄ ), gallium sulfate (Ga ₂ (SO ₄ ) ₃ ), titanium sulfate (Ti (SO ₄ ) ₂ ), at least one selected from the group consisting of nickel sulfate (NiSO ₄ ), or two or more, and the curable composition for sealing materials according to (I),
(III). The curable composition for sealing materials according to (I), wherein the component (D) is zeolite and / or silica gel,
(IV). The curable composition for sealing materials according to any one of (I) to (III), wherein the blending part number of the component (D) is 100 parts by weight with respect to 100 parts by weight of the component (A),
(V). The curable composition for sealing materials according to any one of (I) to (IV), wherein the number average molecular weight of the isobutylene polymer containing an alkenyl group as the component (A) is 3,000 to 50,000. ,
(VI). The curable composition for sealing materials according to any one of (I) to (V), wherein the component (B) is an organohydrogenpolysiloxane.
(VII). The sealing material curable composition according to any one of (I) to (VI), wherein the sealing material composition is an organic EL sealing material,
(VIII). A curable composition for organic EL sealing materials according to (VIII), wherein no sticky moisture getter agent is used when the sealing material is used,
(IX). A sealing material obtained by crosslinking the curable composition for a sealing material according to any one of (I) to (VIII),
About.

  Since the polyisobutylene-based sealing material obtained from the curable composition for sealing materials of the present invention has hygroscopicity and gas barrier properties, it is used in various fields such as electric / electronic, automobile, energy and medical treatment. It can be used in a wide range of applications that require hygroscopicity, gas barrier properties, impact relaxation properties, and the like. In addition, such a curable composition for a sealing material can be handled in the same manner as adhesives and potting agents such as coating, injection, and screen printing, and by press molding, injection molding, transfer molding, extrusion molding, etc. It can be obtained efficiently.

  The component (A) used in the present invention is an isobutylene polymer having at least one alkenyl group capable of hydrosilylation reaction in the molecule. Here, the isobutylene polymer is not limited to those in which all of the monomer units are formed from isobutylene units, but includes those having monomer units copolymerizable with isobutylene in the isobutylene polymer. Sure. However, the monomer having copolymerizability with isobutylene is preferably contained in a range that does not significantly impair the low water absorption and gas barrier properties caused by the isobutylene unit, and is preferably 50% by weight or less, more preferably 30% by weight or less. Particularly preferably, the range is 20% by weight or less.

  Examples of such monomer components include olefins having 4 to 12 carbon atoms, vinyl ethers, aromatic vinyl compounds, vinyl silanes, allyl silanes, and the like. Specific examples of such copolymer components include 1-butene, 2-butene, 2-methyl-1-butene, 3-methyl-1-butene, pentene, 4-methyl-1-pentene, hexene, Vinylcyclohexane, methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, styrene, α-methyl styrene, dimethyl styrene, pt-butoxy styrene, p-hexenyloxy styrene, p-allyloxy styrene, p-hydroxy styrene , Β-pinene, indene, vinyldimethylmethoxysilane, vinyltrimethylsilane, divinyldimethoxysilane, divinyldimethylsilane, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, trivinylmethylsilane, tetravinylsilane Allyldimethylmethoxysilane, Examples include allyltrimethylsilane, diallyldimethoxysilane, diallyldimethylsilane, γ-methacryloyloxypropyltrimethoxysilane, and γ-methacryloyloxypropylmethyldimethoxysilane. Particularly preferably, all of the monomer units are formed from isobutylene units.

  The number average molecular weight (GPC method, converted to polystyrene) of the isobutylene polymer (A) is preferably about 2,000 to 100,000, more preferably 3, from the viewpoint of easy handling and rubber hardness after crosslinking. 000 to 50,000. Generally, as the number average molecular weight increases, the hardness of the resulting crosslinked rubber tends to decrease.

  The alkenyl group is not particularly limited as long as it is a group containing a carbon-carbon double bond that is active for hydrosilylation reaction. Examples of the alkenyl group include aliphatic unsaturated hydrocarbon groups such as vinyl group, allyl group, methylvinyl group, propenyl group, butenyl group, pentenyl group, and hexenyl group, cyclopropenyl group, cyclobutenyl group, cyclopentenyl group, cyclopentyl group, and the like. Examples thereof include cyclic unsaturated hydrocarbon groups such as hexenyl groups, methacryl groups and the like. Among these, an allyl group is preferable from the viewpoint of high activity for hydrosilylation reaction and relatively easy introduction of an alkenyl group.

  In the component (A) in the present invention, the alkenyl group capable of hydrosilylation reaction may be present at the main chain end or side chain of the isobutylene polymer, or may be present in both. In particular, when the alkenyl group is at the end of the main chain, the effective network chain amount of the isobutylene polymer component contained in the finally formed cured product is increased, so that it has low strength but high strength and low compression set. This is preferable from the viewpoint of easily obtaining a rubber elastic body.

  As the method for producing the component (A) of the present invention, a compound having an unsaturated group in a polymer having a functional group such as a hydroxyl group as disclosed in JP-A-3-152164 and JP-A-7-304969 is disclosed. To introduce an unsaturated group into the polymer. In addition, to introduce an unsaturated group into a polymer having a halogen atom, a method of performing a Friedel-Crafts reaction with an alkenylphenyl ether, a method of performing a substitution reaction with allyltrimethylsilane in the presence of a Lewis acid, various phenols and Friedel For example, a method in which the above alkenyl group introduction method is used in combination with the introduction of a hydroxyl group by carrying out a kraft reaction. Furthermore, a method of introducing an unsaturated group at the time of polymerization of a monomer as disclosed in US Pat. No. 4,316,973, Japanese Patent Laid-Open No. 63-105005, and Japanese Patent Laid-Open No. 4-288309 is also possible.

  The alkenyl group should be present in an amount exceeding an average of 1 in one molecule of the polymer (A), preferably 5 or less. When the number of alkenyl groups contained in one molecule of the polymer (A) is 1 or less on average, the curability is insufficient and the resulting network structure is incomplete, and a good molded product is obtained. Absent. Further, when the number of alkenyl groups contained in one molecule increases, the network structure becomes too dense, so that the resulting molded product is hard and brittle, which is not preferable. In particular, when the number is 5 or more, the tendency becomes remarkable.

  The compound having at least two hydrosilyl groups in one molecule as the component (B) in the present invention can be used without particular limitation as long as it has a hydrosilyl group, but has a number average molecular weight of 400 to 3,000. The thing of 500-1,000 is more preferable. When the number average molecular weight is less than 400, it is volatilized at the time of heat curing and a sufficient cured product cannot be obtained, and when it exceeds 3,000, a sufficient curing rate cannot be obtained. Examples of such compounds include organohydrogenpolysiloxanes modified with organic groups from the standpoint of availability of raw materials and compatibility with the component (A). These (B) components are preferably those having good compatibility with the (A) component. In particular, when the viscosity of the whole system is low, use of a material having low compatibility may cause phase separation and cause poor curing. Specifically showing the structure of such an organohydrogenpolysiloxane, for example,

(In the formula, 1 <b + c ≦ 40, 1 <b ≦ 20, 0 <c ≦ 38. R is a hydrocarbon group having 2 to 20 carbon atoms in the main chain and containing one or more phenyl groups. You may)

(In the formula, 0 ≦ d + e ≦ 40, 0 ≦ d ≦ 20, 0 <e ≦ 38. R is a hydrocarbon group having 2 to 20 carbon atoms in the main chain and containing one or more phenyl groups. Or)

(In the formula, 3 ≦ f + g ≦ 20, 1 <f ≦ 20, 0 <g ≦ 18. R is a hydrocarbon group having 2 to 20 carbon atoms in the main chain and containing one or more phenyl groups. Or a chain-like or cyclic group represented by

  Specific examples of the (B) component having relatively good compatibility with the (A) component and the (C) component, or relatively good dispersion stability and curing speed include the following.

In the formula, 1 <k + l ≦ 20, 1 <k ≦ 19, 0 <l ≦ 18, and R is a hydrocarbon group having 8 or more carbon atoms.

  As a more specific example of the component (B), methyl hydrogen polysiloxane is used in order to ensure compatibility with the component (A) and to adjust the amount of SiH, α-olefin, styrene, α-methylstyrene, Examples include compounds modified with allyl alkyl ethers, allyl alkyl esters, allyl phenyl ethers, allyl phenyl esters, and the like, and examples include the following structures.

However, 1 <p + q ≦ 20, 1 <p ≦ 19, and 0 <q ≦ 18.

  The amount of the hydrosilyl group-containing compound as the component (B) in the present invention is such that [total amount of hydrosilyl groups in the component (B)] / [total amount of alkenyl groups in the component (A)] is 0.5 or more. Preferably, it is 0.7 or more. When [total amount of hydrosilyl groups in component (B)] / [total amount of alkenyl groups in component (A)] is less than 0.5, the resulting sealing material has a low crosslink density, and thus is easily plastically deformed. It lacks long-term reliability as a material. In addition, if [total amount of hydrosilyl groups in component (B)] becomes excessive compared to [total amount of alkenyl groups in component (A)], formation of a three-dimensional network skeleton becomes difficult, and similarly obtained The resulting sealing material has a low crosslinking density and lacks long-term reliability as a sealing material. Thus, it is necessary to pay attention to both the lower limit and the upper limit for the amount of component (B) used.

It does not specifically limit as a hydrosilylation catalyst which is (C) component of this invention, Arbitrary things can be used. For example, solid platinum supported on a carrier such as chloroplatinic acid, platinum alone, alumina, silica, carbon black, etc .; platinum-vinylsiloxane complex {eg, Pt _X (ViMe ₂ SiOSiMe ₂ Vi) _y , Pt [(MeViSiO) ₄ ] _z }; platinum-phosphine complex {eg, Pt (PPh ₃ ) ₄ , Pt (PBu ₃ ) ₄ }; platinum-phosphite complex {eg, Pt [P (OPh) ₃ ] ₄ , Pt [P (OBu) ₃ ] ₄ (wherein Me represents a methyl group, Bu represents a butyl group, Vi represents a vinyl group, Ph represents a phenyl group, x, y, and z represent integers), Pt ( _{acac) 2} (However, acac represents acetylacetonato), also platinum described in U.S. Pat. No. 3,159,601 and 3,159,662 of Ashby et al - hydrocarbon complex And platinum alcoholate catalysts described in Lamoreaux et al U.S. Pat. No. 3,220,972 may also be mentioned.
Examples of catalysts other than platinum compounds include RhCl (PPh ₃ ) ₃ , RhCl ₃ , Rh / Al ₂ O ₃ , RuCl ₃ , IrCl ₃ , FeCl ₃ , AlCl ₃ , PdCl ₂ .2H ₂ O, NiCl _2. , TiCl _{4 and the} like.

These catalysts may be used alone or in combination of two or more. From the viewpoint of catalytic activity, chloroplatinic acid, platinum-olefin complexes, platinum-vinylsiloxane complexes, Pt (acac) _{2 and the} like are preferable. Although there is no restriction | limiting in particular as catalyst usage-amount, It is good to use in the range of 10 ^<-8 > ^-10 < ^-1 > mol with respect to ¹ mol of alkenyl groups in (A) component. Preferably, it is used in the range of 10 ⁻⁶ to 10 ⁻² mol. If it is less than 10 ⁻⁸ mol, the curing rate is slow and the curability is likely to be unstable. On the other hand, if it exceeds 10 ⁻¹ mol, it is difficult to ensure the pot life, which is not preferable.

The moisture absorbent as component (D) of the present invention adsorbs moisture in the curable composition for sealing materials of the present invention, and adsorbs moisture entering from the outside as a sealing material after crosslinking in the sealing material. It is used for the purpose of doing. Such a hygroscopic agent is not particularly limited as long as it has a function capable of adsorbing at least moisture, but a compound that adsorbs moisture chemically and maintains a solid state even when moisture is absorbed is preferable. Although the kind in particular of desiccant is not restrict | limited, For example, 1 type single or 2 types or more combinations, such as an oxide, a halide, a sulfate, a perchlorate, carbonate, and an organic substance, are mentioned. More specifically, calcium oxide (CaO), barium oxide (BaO), magnesium oxide (MgO), strontium oxide (SrO), phosphorus pentoxide (P ₄ O ₁₀ ), alumina (Al ₂ O ₃ ), lithium sulfate (Li ₂ SO ₄ ), sodium sulfate (Na ₂ SO ₄ ), calcium sulfate (CaSO ₄ ), magnesium sulfate (MgSO ₄ ), cobalt sulfate (CoSO ₄ ), gallium sulfate (Ga ₂ (SO ₄ ) ₃ ), sulfuric acid Examples thereof include titanium (Ti (SO ₄ ) ₂ ) and nickel sulfate (NiSO ₄ ). In addition, organic compounds having hygroscopicity can be used as the hygroscopic agent of the present invention. Further, since the moisture absorption is further improved and leakage can be efficiently prevented even when a deliquescent desiccant is used, the desiccant is in a particulate form and is uniformly dispersed in the desiccant-containing layer. It is preferable. In this case, the average particle size of the desiccant is preferably 20 μm or less, and more preferably a value within the range of 0.1 to 10 μm. In the present invention, an oxide is preferable from the viewpoints of availability, environmental friendliness, and the like.

  The hygroscopic agent (D) is preferably used in an amount of 0.5 to 50 parts by weight, more preferably 1 to 20 parts by weight based on 100 parts by weight of the isobutylene polymer (A) containing more than one alkenyl group. preferable. If it is less than 0.5 part by weight, moisture absorption is insufficient, and if it is used in an amount exceeding 50 parts by weight, the curable composition for sealing material loses fluidity and the workability is lowered, which is not preferable.

  In addition, the curable composition for sealing materials composed of the components (A) to (D) of the present invention includes a storage stability improver, heat resistance and the like for the purpose of improving the storage stability of the curable composition for sealing materials. Antioxidants and UV absorbers for improving weather resistance, various pigments for coloring purposes, metal soaps, waxes, silicon compounds for improving surface properties, and other surfactants and solvents as required Can be used.

  The storage stability improver is not particularly limited as long as it is an ordinary stabilizer known as a storage stabilizer of the component (B) of the present invention and can achieve the intended purpose. is not. Specifically, a compound containing an aliphatic unsaturated bond, an organic phosphorus compound, an organic sulfur compound, a nitrogen-containing compound, a tin compound, an organic peroxide, or the like can be preferably used. Specifically, 2-benzothiazolyl sulfide, benzothiazole, thiazole, dimethylacetylene dicarboxylate, diethylacetylene dicarboxylate, 2,6-di-t-butyl-4-methylphenol, butylhydroxyanisole, vitamin E, 2- (4-morphodinyldithio) benzothiazole, 3-methyl-1-buten-3-ol, acetylenically unsaturated group-containing organosiloxane, acetylene alcohol, 3-methyl-1-butyl-3-ol , Diallyl fumarate, diallyl maleate, diethyl fumarate, diethyl maleate, dimethyl maleate, 2-pentenenitrile, 2,3-dichloropropene, and the like, but are not limited thereto.

  In addition, the method for obtaining the curable composition for a sealing material of the present invention is not particularly limited. However, the components (A) to (D) and various additives and fillers used as necessary are mixed with a planetary mixer. And a mixing method using a rotary mixer such as a two-axis disperser, a kneader, a bumper mixer, and a roll. Here, in the curable composition for sealing materials of the present invention, the moisture absorbent as the component (D) is uniformly dispersed and stabilized, and moisture contained in the curable composition for sealing materials is removed as much as possible. It is desirable. If the hygroscopic material is not uniformly dispersed in the component (A), the properties of the composition greatly change over time.

  In addition, as a method for obtaining the sealing material from the curable composition for a sealing material of the present invention, the same method as that of a commonly used thermosetting liquid sealing material, that is, application or injection with a dispenser, mask printing, etc. A method such as screen printing can be applied. Moreover, it is applicable also to the method of obtaining a rubber molding, such as press molding, injection molding, transfer molding, and extrusion molding.

  Moreover, in these various handling methods, the curable composition for sealing materials of the present invention can be handled as a one-liquid form containing all the components, or the (B) component and the (C) component are not mixed. It is also possible to handle it as a two-liquid form in which components are distributed to two liquids. In the former case, since the reaction can proceed gradually even at room temperature, storage at a low temperature is required, but the trouble of mixing two liquids at the time of molding can be omitted. In the latter case, it is necessary to mix the two liquids at the time of molding and apply, fill, and inject in a state that does not contain bubbles, but for long-term storage of the curable composition for sealing materials. Is advantageous. In handling such a curable composition for a liquid seal material in a two-component form, a two-component mixed discharge device used for a two-component urethane resin and an epoxy resin, and a liquid injection developed for liquid silicone A two-component mixing and discharging device used in a molding system can be used.

  The sealing material obtained from the curable composition for a sealing material of the present invention has excellent hygroscopicity, gas barrier properties, impact resistance, and in various fields such as electric / electronic, automobile, energy, medical treatment, etc. It can be used for a wide range of applications that require high sealing performance.

  Next, although the curable composition for sealing materials of this invention and the sealing material obtained from it are demonstrated concretely by an Example, this invention is not limited only to these Examples.

(Production Example 1)
After attaching a three-way cock to a 2 L pressure-resistant glass container and replacing the inside of the container with nitrogen, 138 ml of ethylcyclohexane (dried by leaving it overnight with molecular sieves 3A for more than one night) in the container and toluene 1012 ml of 1,4-bis (α-chloroisopropyl) benzene (8.14 g, 35.2 mmol) was added (dried by leaving it overnight with Molecular Sieves 3A for 1 night or more).

  Next, after a liquefied collection tube made of pressure-resistant glass with a needle valve containing 254 ml (2.99 mol) of isobutylene monomer was connected to a three-way cock, the polymerization vessel was placed in a -70 ° C dry ice / ethanol bath and cooled. The inside of the container was depressurized using a vacuum pump. After opening the needle valve and introducing isobutylene monomer into the polymerization vessel from the liquefied gas sampling tube, nitrogen was introduced from one side of the three-way cock to return the inside of the vessel to normal pressure. Next, 0.387 g (4.15 mmol) of 2-methylpyridine was added. Next, 4.90 ml (44.7 mmol) of titanium tetrachloride was added to initiate polymerization. After 70 minutes of reaction time, 9.65 g (13.4 mmol) of allyltrimethylsilane was added to carry out an allyl group introduction reaction at the polymer end. After 120 minutes of reaction time, the reaction solution was washed 4 times with 200 ml of water, and then the solvent was distilled off to obtain an allyl-terminated isobutylene polymer (a-1).

The yield was calculated from the yield of the polymer thus obtained, Mn and Mw / Mn were determined by GPC method, and the terminal structure was determined by protons belonging to each structure by 300 MHz ¹ H-NMR analysis (proton derived from initiator: 6 It was determined by measuring and comparing the intensity of the resonance signal of 5-7.5 ppm and the peak of the allyl group derived from the polymer terminal (4.97 ppm: = CH ₂ , 5.79 ppm: -CH = C). ¹ H-NMR was measured in a carbon tetrachloride / heavy acetone using a Varian Gemini 300 (300 MHz for ¹ H).
GPC was performed using Waters LC Module 1 as a liquid feeding system, and Shodex K-804 as a column. Molecular weight is given as a relative molecular weight relative to polystyrene standards. The analytical values of the polymer are Mn = 5800, Mw / Mn = 1.39, Fn (v) = 1.88 (in NMR analysis, the number of allyl groups per molecule of the aromatic ring serving as an initiator residue). there were.

(Production Example 2)
In the presence of a platinum catalyst, 0.5 equivalent of an α-olefin of the total amount of hydrosilyl groups was added to methylhydrogen silicone having an average of (-Si-O-) repeating units of 7.5, and an average of about The compound (b-1) which has 5.5 hydrosilyl groups was obtained. The Si—H group content of this compound was 6 mmol / g.

(Examples 1-2)
According to the compounding amount shown in Table 1, as the component (A), the allyl group-terminated isobutylene polymer (a-1) obtained in Production Example 1, and as the component (D), CaO (manufactured by Inoue Lime Co., Ltd., VESTA PP) ( d-1), an antioxidant (manufactured by ADEKA, ADK STAB AO-50), and a plasticizer (manufactured by Idemitsu Kosan Co., Ltd., PAO5010) were kneaded with a roll. Subsequently, the resulting mixture was heated and stirred with a planetary mixer under reduced pressure to remove moisture. After further cooling, hydrosilyl compound (b-1) as component (B), platinum vinylsiloxane (3% platinum xylene solution) (c-1) as component (C), and acetylene alcohol (MBO: 2- Aldrich) Methyl-3-butyn-2-ol), adhesion promoter (SILQUEST A-187 SILANE, manufactured by Momentive Performance Materials Co., Ltd., ethyl silicate 40 manufactured by Colcoat Co., Ltd., tri-n-butyl borate manufactured by Tokyo Chemical Industry Co., Ltd.) Mixed.

  The composition thus obtained was in a liquid state, and after defoaming, a film was formed on an iron base (made by Taisu base material) of material SS (JIS G 3101) washed with toluene with a 100 μm coater, and 80 ° C. It heat-processed for 30 minutes with the hot air dryer. The obtained test piece was put into a constant temperature and humidity machine under conditions of 65 ° C. and 90% RH to evaluate the progress of rust on the iron base. These results are shown in Table 1.

(Comparative Examples 1-2)
According to the blending amount shown in Table 1, as the component (A), the allyl group-terminated isobutylene polymer (a-1) obtained in Production Example 1, an antioxidant (manufactured by ADEKA, ADK STAB AO-50), a plasticizer ( Idemitsu Kosan Co., Ltd., PAO5010) was kneaded with a roll. Subsequently, the resulting mixture was heated and stirred with a planetary mixer under reduced pressure to remove moisture. After further cooling, hydrosilyl compound (b-1) as component (B), platinum vinylsiloxane (3% platinum xylene solution) (c-1) as component (C), and acetylene alcohol (MBO: 2- Aldrich) Methyl-3-butyn-2-ol), adhesion promoter (SILQUEST A-187 SILANE, manufactured by Momentive Performance Materials Co., Ltd., ethyl silicate 40 manufactured by Colcoat Co., Ltd., tri-n-butyl borate manufactured by Tokyo Chemical Industry Co., Ltd.) Mixed.

  The composition thus obtained was in a liquid state, and after defoaming, a film was formed on an iron base (made by Taisu base material) of material SS (JIS G 3101) washed with toluene with a 100 μm coater, and 80 ° C. It heat-processed for 30 minutes with the hot air dryer. The obtained test piece was put into a constant temperature and humidity machine under conditions of 65 ° C. and 90% RH to evaluate the progress of rust on the iron base. These results are shown in Table 1.

Claims (8)

( A) an isobutylene-based polymer containing in the molecule at least one alkenyl group capable of hydrosilylation reaction ,
(B) a compound having at least two hydrosilyl groups in the molecule ;
(C) hydrosilylation catalyst , and (D) a hygroscopic agent
A curable composition for an organic EL sealing material having fluidity at room temperature,
A curable composition for organic EL sealing materials, wherein a sticky moisture getter agent is not used when the sealing material is used. The component (D) is calcium oxide (CaO), barium oxide (BaO), magnesium oxide (MgO), strontium oxide (SrO), phosphorus pentoxide (P ₄ O ₁₀ ), lithium sulfate (Li ₂ SO ₄ ), Sodium sulfate (Na ₂ SO ₄ ), calcium sulfate (CaSO ₄ ), magnesium sulfate (MgSO ₄ ), cobalt sulfate (CoSO ₄ ), gallium sulfate (Ga ₂ (SO ₄ ) ₃ ), titanium sulfate (Ti (SO ₄ ) _The curable composition for organic EL sealing materials according to claim 1, wherein the curable composition is at least one selected from the group consisting of ₂ ) and nickel sulfate (NiSO ₄ ). The curable composition for organic EL sealing materials according to claim 1, wherein the component (D) is zeolite and / or silica gel. The curable composition for organic EL sealing materials according to any one of claims 1 to 3, wherein the amount of the (D) component is 1 to 20 parts relative to 100 parts by weight of the (A) component. . The number average molecular weight of the isobutylene-based polymer containing an alkenyl group as the component (A) is 3,000 to 50,000, and the curability for an organic EL sealing material according to any one of claims 1 to 4. Composition. The curable composition for organic EL sealing materials according to any one of claims 1 to 5, wherein the component (B) is an organohydrogenpolysiloxane. The curable composition for organic EL sealing materials according to any one of claims 1 to 6, which does not contain an inorganic filler. Any organic EL sealant curable composition according to item 1, the organic EL sealing material obtained by heat molding according to claim 1-7.