JP2855196B2 - Sealant for multilayer transparent plate and multilayer transparent plate - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a sealant for a multilayer transparent plate and a multilayer transparent plate using the sealant. More specifically, the present invention relates to a sealant for a multilayer transparent plate having a large adhesive force, a low moisture permeability, an excellent impact resistance, and a small temperature dependency of an elastic modulus, and a multilayer transparent plate using the sealant.

[Problems to be solved by conventional technology and invention]

2. Description of the Related Art Conventionally, in an aircraft, a high-speed train, and the like, a multilayer transparent plate in which transparent plates are laminated in multiple layers has been used for windows and the like. Furthermore, in recent years, multilayer transparent plates have been used in high-rise buildings and houses in order to improve heat insulation or soundproofing. This multilayer transparent plate has a structure in which at least two transparent plates are joined with a sealant via a spacing material, and a multilayer transparent plate including three or more transparent plates has been put to practical use.

In these multilayer transparent plates, if moisture is present between the transparent plates, it causes fogging.Therefore, when manufacturing a multilayer transparent plate, dry air is sealed between the transparent plates, or in the space holding material of the transparent plates. For example, a desiccant made of zeolite or the like is attached to prevent moisture from entering between transparent plates or remove moisture. In addition, the sealant used for bonding the transparent plate has not only a large adhesive strength with the transparent plate and a low moisture permeability, but also enhances the impact resistance of the multilayer transparent plate to prevent moisture penetration due to impact. As described above, it is also required that the impact resistance (elastic modulus) is excellent and the temperature dependence of the elastic modulus is small. As sealants satisfying these requirements, polysulfide-based sealants and silicone-based sealants are known, but their effects are not sufficient, and development of more excellent sealants is desired.

[Means for solving the problem]

Therefore, the present inventor has conducted intensive studies to obtain a sealant satisfying the above properties, and as a result, those having a specific hydroxyl group-containing compound, a polyisocyanate compound, a filler and a viscosity reducing agent mixed in a specific ratio have a large adhesive force. The present invention was found to be able to be used as a sealant having low moisture permeability, excellent impact resistance, and low temperature dependence of elastic modulus.

That is, the present invention relates to a sealant for a multilayer transparent plate for joining at least two transparent plates with a spacing material interposed between the transparent plates, wherein (A) at least 50% by weight or more has a number average molecular weight. A hydroxyl group-containing compound comprising a hydroxyl group-containing liquid diene polymer of 500 to 9000 and / or a hydride thereof, (B) the hydroxyl group-containing compound (A)
A polyisocyanate compound in an amount such that the molar ratio of isocyanate groups to hydroxyl groups present therein is in the range of 0.5 to 4, (C) 30 to 300 parts by weight of filler based on 100 parts by weight of the hydroxyl group-containing compound (A), and (D) A sealant for a multilayer transparent plate comprising 10 to 200 parts by weight of a viscosity reducing agent having a flash point of 40 ° C. or more per 100 parts by weight of the hydroxyl group-containing compound (A). The present invention also provides a multilayer transparent plate obtained by bonding the transparent plates described above with the sealant with a spacing member interposed between the transparent plates.

In the present invention, the multilayer transparent plate refers to a plate obtained by joining at least two transparent plates with a sealant interposed therebetween with a spacing member disposed between the transparent plates.

The component (A) in the sealant of the present invention is a hydroxyl group-containing compound comprising at least 50% by weight or more of a hydroxyl group-containing liquid diene polymer having a number average molecular weight of 500 to 9000 and / or a hydride thereof.

Here, as the hydroxyl group-containing liquid diene polymer having a number average molecular weight of 500 to 9000, any known one can be used,
Alternatively, it can be easily manufactured by a known method.
For example, a diene monomer having 4 to 22 carbon atoms (butadiene, isoprene, chloroprene, 1,3-pentadiene, cyclopentadiene, or the like) is converted to an aqueous peroxide system or an azo compound having a hydroxyl group (for example, 2,2'-azobis [2-methyl-N − (2-
Hydroxyethyl) propionamide], a peroxide having a hydroxyl group (for example, cyclohexanone peroxide, etc.) or the like is used as a polymerization initiator to obtain a hydroxyl group-containing liquid diene polymer. Here, the amount of the polymerization initiator is not particularly limited, but 1.0 to 50 g of hydrogen peroxide, 2,2'-azobis [2-methyl-N- (2-hydroxyethyl) propionamide based on 100 of the diene monomer. 5.0-100 g and cyclohexanone peroxide 5.0-100 g are suitable. Although the polymerization can be carried out without a solvent, it is preferable to use a solvent for ease of control of the reaction, and as the solvent, ethanol, isopropanol, n-butanol or the like is usually used. The reaction temperature is suitably from 80 to 150 ° C, and the reaction time is suitably from 0.5 to 15 hours.

Furthermore, a diene monomer is anionically polymerized using a catalyst such as naphthalenedilithium to produce a living polymer, and a desired hydroxyl group-containing liquid diene polymer can also be obtained by reacting a monoepoxy compound or the like. . The polymerization in this case can be carried out without a solvent, but it is preferable to use a solvent for the same reason as in the case of radical polymerization. As the solvent, a saturated hydrocarbon such as hexane and cyclohexane is used. At this time, the reaction temperature is suitably 50 to 100 ° C., and the reaction time is suitably 1 to 10 hours. Further, at the time of polymerization, an addition-polymerizable monomer having 2 to 22 carbon atoms, such as butene, pentene, styrene, α-methylstyrene, acrylonitrile, acrylic acid and its ester, methacrylic acid and its ester at a ratio of 50 mol% or less to the diene monomer. , Vinyl chloride, vinyl acetate,
Acrylamide and the like can be added.

If the solution is distilled under reduced pressure after the completion of the polymerization reaction, the solvent is removed, and a hydroxyl group-containing liquid diene polymer is obtained. The number average molecular weight of the hydroxyl group-containing liquid diene polymer thus obtained is usually 500 to 9000, preferably 800 to 5000, and the hydroxyl group content is 0.1 to 10 meq / g, preferably 0.3 to 7
meq / g. Here, when the number average molecular weight is less than 500, it is not preferable because the elasticity of the obtained sealant is inferior.
If it exceeds, the viscosity becomes high or it becomes solid, which is not preferable in handling.

In addition, the hydroxyl group of the liquid diene polymer may be located at any position on the molecular chain terminal or inside the molecular chain, but is preferably at the molecular chain terminal. In the present invention, two or more kinds of hydroxyl group-containing liquid diene polymers can be used in combination. In particular, when excellent heat resistance and weather resistance are required, the double bond in the skeleton of the hydroxyl group-containing diene polymer can be hydrogenated and used.

The hydride of the hydroxyl group-containing liquid diene polymer can be obtained by hydrogenating the hydroxyl group-containing liquid diene polymer by a known method using a homogeneous catalyst, a heterogeneous catalyst, or the like.

When a homogeneous catalyst is used, saturated hydrocarbons such as hexane and cyclohexane, and aromatic hydrocarbons such as benzene, toluene and xylene are used as solvents at normal reaction to 150 ° C and normal pressure to 50 kg / cm ² G under hydrogen pressure. A hydrogenation reaction is carried out. As the homogeneous catalyst, a Ziegler catalyst or the like obtained by combining a transition metal halide with an alkylated product such as aluminum, alkaline earth metal or alkali metal is used in an amount of about 0.01 to 0.1 mol% per double bond of the polymer. The reaction is usually completed in 1 to 24 hours.

When a heterogeneous catalyst or the like is used, saturated hydrocarbons such as hexane and cyclohexane, aromatic hydrocarbons such as benzene, toluene, and xylene, ethers such as diethyl ether, tetrahydrofuran, and dioxane; alcohols such as ethanol and isopropanol; These mixed systems are used as solvents and at normal temperature to 200 ° C at normal pressure to 100 kg / c.
The hydrogenation reaction is performed under a hydrogen pressure of m ² G. Heterogeneous catalysts include nickel, cobalt, palladium, platinum,
A catalyst such as rhodium or ruthenium is used alone or supported on a carrier such as silica, diatomaceous earth, alumina or activated carbon. The amount used is suitably 0.05 to 10% by weight based on the weight of the polymer. In addition to using these catalysts alone,
Two or more kinds may be used as a mixture. The reaction is usually completed in 1 to 48 hours.

After completion of the reaction, the catalyst is filtered off, and the solution is distilled under reduced pressure to remove the solvent and obtain a hydride of a hydroxyl group-containing liquid diene polymer. The hydride of this hydrogen group-containing liquid diene polymer usually has a number average molecular weight of 600 to 10,000, preferably 800 to 5000, and a hydroxyl group content of 0.1 to 10 meq / g.
Is preferred.

The ratio (hydrogenation rate) of hydrogenation of unsaturated double bonds in the polymer after the hydrogenation reaction is represented by the following formula.

A: Bromine value of polymer before hydrogenation B: Bromine value of polymer after hydrogenation The hydrogenation rate of the hydride is 50% or more, preferably 70% or more. In the present invention, two or more hydrides of a hydroxyl group-containing liquid diene polymer may be mixed and used, or a mixture of a hydroxyl group-containing liquid diene polymer and a hydride thereof may be used.

Furthermore, in order to obtain a cured product having good physical properties, the average number of hydroxyl groups per molecule of the hydride of the hydroxyl group-containing liquid diene polymer is 1.7 or more, preferably 2.0 or more.

The average number of hydroxyl groups per molecule can be represented by the following formula.

In the present invention, at least 50% by weight of the hydroxyl group-containing compound as the component (A) must be the hydroxyl group-containing liquid diene polymer and / or a hydride thereof. Here, when the content of the hydroxyl group-containing liquid diene polymer and / or its hydride is 50% by weight or less, moisture permeability and rubber elasticity are inferior.

In addition to the hydroxyl group-containing liquid diene polymer and its hydride, the hydroxyl group-containing compounds that can be used as the component (A) include polyol compounds and monofunctional alcohol compounds, and these are used in an amount of less than 50% by weight. be able to.

Here, the polyol compound is a compound having two or more hydroxyl groups in one molecule, and the following low molecular weight polyol compounds, polymerization type polyol compounds and castor oil-based polyol compounds are preferably used.

As low molecular polyol compounds, primary polyols,
Either a secondary polyol or a tertiary polyol may be used. Specifically, for example, 1,2-propylene glycol,
Dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 2,3-butanediol, 1,2-pentanediol, 2,3-pentanediol, 2,5-hexanediol,
2,4-hexanediol, 2-ethyl-1,3-hexanediol, cyclohexanediol, glycerin, N, N-bis-2-hydroxypropylaniline, N, N'-bishydroxyisopropyl-2-methylpiperazine, bisphenol At least one such as a propylene oxide adduct of A
Low molecular weight polyols containing hydrogen groups bonded to two secondary carbons.

Further, as the polyol compound, ethylene glycol, diethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and triglycerol containing no hydroxyl group bonded to the secondary carbon are used. Methylolpropane, pentaerythritol,
Dipentaerythritol and the like can also be used. Its molecular weight is usually in the range of 50-500.

Examples of the polymerizable polyol compound used as a polyurethane raw material include polyether polyols and modified products thereof, polytetraethylene ether glycol, tetrahydrofuran / alkylene oxide copolymerized polyols, epoxy resin-modified polyols, polyester polyols, polydiene-based polyols, and the like. Saponified ethylene-vinyl acetate copolymer and the like can be mentioned. The number average molecular weight of these polyol compounds is usually 500 to 10,000
It is 0.

Furthermore, examples of castor oil-based polyol compounds include castor oil, hydrogenated castor oil, castor oil transesterified products, and the like. These polyol compounds can be used as a mixture of two or more kinds.

The monofunctional alcohol compound can be used for the purpose of improving adhesion and lowering the viscosity of the system. However, if too much is used, the elasticity of the system is lost. %. As the monofunctional alcohol compound, 1-butanol, 1-octanol, 1-dodecanol and the like are usually used.

In the present invention, the polyisocyanate compound used as the component (B) is an organic compound having two or more isocyanate groups in one molecule, and is a reactive isocyanate for a hydroxyl group of the above-mentioned hydroxyl group-containing liquid diene polymer. It has a group. Examples of the polyisocyanate compound include ordinary aromatic, aliphatic and alicyclic compounds such as tolylene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), carbodiimide-modified diphenylmethane diisocyanate, and polymethylene polyisocyanate. Phenyl isocyanate, phenylene diisocyanate, naphthalene-
1,5-diisocyanate, o-toluidine diisocyanate, triphenylmethane triisocyanate, tris (isocyanatephenyl) thiophosphate, isopropylbenzene-2,4-diisocyanate, xylylene diisocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI) , Hexamethylene diisocyanate, dodecane diisocyanate, lysine diisocyanate, lysine ester triisocyanate, 1,6,11
-Undecane triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene triisocyanate, trimethylhexamethylene diisocyanate, transcyclohexane-1,4
-Diisocyanate, bicycloheptane triisocyanate, isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated tetramethyl xylylene diisocyanate, cyclized trimer of the polyisocyanate compound ( Modified isocyanurate), buret modified product, ethylene glycol, trimethylolpropane, polyether polyol, polymer polyol, polytetramethylene ether glycol, polyester polyol, acrylic polyol, polyalkadiene polyol, partially saponified ethylene-vinyl acetate copolymer Coalescence, an addition reaction product of a polyol compound such as a castor oil-based polyol and the polyisocyanate compound is used. Can be

These polyisocyanate compounds may be used as a mixture of two or more kinds. Further, the isocyanate groups of these polyisocyanate compounds may be used as phenols, oximes, imides, mercaptans, alcohols, ε.
-Caprolactam, ethyleneimine, α-pyrrolidone,
A so-called blocked isocyanate compound blocked with a blocking agent such as diethyl malonate, sodium hydrogen sulfite, boric acid and the like can also be used.

With regard to the mixing ratio of the component (B), the isocyanate group (NC) of the polyisocyanate compound (B) is based on the hydroxyl group (OH) of the hydroxyl group-containing compound (A).
O) (NCO / OH) is finally 0.5 to 4.0 in molar ratio,
Preferably, it is blended to be 0.7 to 3.5. The mixing ratio is
If it is less than 0.5 or exceeds 4.0, it is not preferable because a solid sealant having elasticity cannot be obtained.

Here, the term "finally" is used because the following various methods are used in producing an actual cured product.

One-shot method: At least components other than the polyisocyanate compound among all the components are mixed to obtain a mixture. The polyisocyanate compound and the components not used in the previous mixing are added to this mixture and mixed to obtain a liquid polymer composition. Preferred NCO / OH (molar ratio) at this time
Is 0.5 to 1.8.

Prepolymer method (1): The prescribed equivalent ratio (NCO / OH) is 1.
In the range of 7 to 25, at least one of the compounds having a hydroxyl group is reacted with the polyisocyanate compound in the presence or absence of some or all of the other additives to obtain a prepolymer. The remaining components are mixed with the prepolymer to obtain a liquid polymer composition. The preferred NCO / OH (molar ratio) at this time is 0.5 to 1.8. In this case, the molar ratio (NCO / OH) of the functional groups involved in the reaction when obtaining the prepolymer is substantially 1.0, so that the final NCO / OH
Is in the range of 0.5 to 1.8. Thus, the final NCO /
OH means the molar ratio of isocyanate groups to hydroxyl groups of all compounds used from the step of forming the prepolymer to the step of curing.

Prepolymer method (2): The prescribed equivalent ratio (NCO / OH) is 1.
All the components are blended in the range of 7 to 4.0 and reacted to obtain a prepolymer. Moisture in the air (water)
And react with.

Next, in the present invention, a filler is used as the component (C).
Either an inorganic filler or an organic filler may be used as the filler. Specifically, the inorganic fillers include zinc, asbestos, alumina, aluminum, kaolin, clay, glass spheres, glass flakes, glass fibers, carbon (channel black, furnace black, acetylene black, thermal black), carbon fibers, and kasumilite , Cryolite, graphite, silica, wollastonite, diatomaceous earth, zinc oxide, magnesium oxide, zirconium oxide,
Titanium oxide, iron oxide, aluminum hydroxide, magnesium hydroxide, slate powder, zeolite, quartz powder, calcium carbonate, magnesium carbonate, talc, potassium titanate, boron nitride, feldspar powder, copper, nickel, molybdenum disulfide, barium sulfate , Whiting, Roseki clay,
Mica, gypsum and the like can be mentioned.

Examples of the organic filler include rubber powder, cellulose, lignin, chitin, leather powder, coconut shell, wood powder, natural fibers such as cotton, hemp, wool, silk, nylon, polyester, vinylon, acetate, and acrylic. Synthetic fibers such as polyethylene, polypropylene, polystyrene,
Examples thereof include synthetic resin powder or granules such as acryl-butadiene-styrene resin, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polymethyl methacrylate, vinyl chloride resin, epoxy resin, and phenol resin. In the present invention, the inorganic filler or the organic filler may be used alone or in combination of two or more.

The compounding ratio of the component (C) is 30 to 300 parts by weight, preferably 100 parts by weight of the hydroxyl group-containing compound as the component (A).
50 to 250 parts by weight. If the compounding ratio is less than 30 parts by weight, thixotropic properties do not appear in the system, which is not preferable. If it exceeds 300 parts by weight, the viscosity of the system becomes extremely high, which is not preferable.

Further, in the present invention, a viscosity reducing agent having a flash point of 40 ° C. or higher is used as the component (D). Specific examples include plasticizers such as dioctyl phthalate, process oils such as paraffin, naphthene, and aroma, olefin oligomers, alkylbenzene, alkylnaphthalene, alkyldiphenylethane, and silicone oil. Here, if the flash point of these viscosity-reducing agents is less than 40 ° C., it is not preferable from the viewpoint of safety during compounding and use.

The mixing ratio of the component (D) is 1 to 200 parts by weight, preferably 100 parts by weight of the hydroxyl group-containing compound as the component (A).
30 to 150 parts by weight. If the compounding ratio is less than 10 parts by weight, the effect of lowering the viscosity of the system is not sufficient,
Exceeding the weight part is not preferred because the elasticity is lost.

The sealant for a multilayer transparent plate of the present invention is the above (A) to
Although the component (D) is an essential component, a catalyst and other additives can be appropriately compounded as required.

To accelerate the curing reaction, triethylenediamine, tetramethylguanidine, N, N, N ', N'-tetramethylhexane 1,6-diamine, N, N, N', N ", N" -pentane are used as catalysts. Methyldiethylenetriamine, bis (2-dimethylaminoethyl) ether, 1,2-dimethylimidazole, N
-Methyl-N '-(2-dimethylamino) -ethylpiperazine, tertiary amines such as diazabicycloundecene, stannasoctoate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin thiocarboxylate, dibutyltin marcatide , Dibutyltin dimaleate, dioctyltin marker peptide, dioctyltin thiocarboxylate, phenylmercury propionate,
An organic metal compound such as lead octenoate, a carboxylate of the tertiary amine, and the like can be added.

These catalysts can be used as component (A), a hydroxyl group-containing compound 100.
Up to 10 parts by weight per part by weight can be added. Ten
Exceeding the parts by weight is not preferable because not only the effect of accelerating the curing becomes a limit but also the risk of local abnormal reaction occurrence (gelation) increases.

Hydrocarbon solvents such as n-hexane, cyclohexane, toluene and xylene; ketone solvents such as methyl ethyl ketone and cyclohexanone; ester solvents such as butyl acetate; ester solvents such as tetrahydrofuran; A solvent such as diethylformamide or dimethylsulfoxide may be blended.

The amount of the solvent is not particularly limited, but is usually 20 parts by weight or less, preferably 10 parts by weight or less based on 100 parts by weight of the hydroxyl group-containing compound.

In order to adjust the adhesion and adhesion, alkylphenol resin, terpene resin, terpene phenol resin, xylene formaldehyde resin, rosin, hydrogenated rosin, coumarone resin, aliphatic petroleum resin, alicyclic petroleum resin and aromatic petroleum resin And the like. Furthermore, anti-aging agents such as hindered phenols, hindered amines, and benzotriazoles, antioxidants, and ultraviolet absorbers are added to improve heat resistance and weather resistance. Phosphorus compounds, halogen compounds, and antimony oxide are used as flame retardants. Or the like, a silicon compound or the like as an antifoaming agent, zeolite, quick lime, or the like as an antifoaming agent, or an organosilicon compound, an organic titanium compound, or the like as an adhesion improver.

The sealant for a multilayer transparent plate of the present invention can be obtained by blending and mixing the above components in a predetermined ratio. In the preparation, a mixing device, a kneading device or the like is used at a temperature of 0 to 120 ° C, preferably 115 to 100 ° C for 0.5 seconds to 8 hours.
The mixture may be stirred and mixed for a time, preferably 1 second to 5 hours.
The preparation of the sealant is usually performed by a one-shot method or a prepolymer method.

In the one-shot method, first, components other than at least the polyisocyanate compound among the above components are blended and mixed under the above-mentioned temperature and time conditions to obtain a mixture. A sealant is obtained by adding the polyisocyanate compound and the additive components not used in the previous mixing to this mixture and mixing them under the above-mentioned temperature and time conditions. The preferred reaction equivalent ratio (NCO / OH) at this time is 0.5 to 2.5.

In the prepolymer method, the predetermined equivalent ratio (NCO / OH) is 1.7
Within a range of from 25 to 25, a prepolymer is obtained by reacting at least one of the hydroxyl group-containing compounds with the polyisocyanate compound in the presence or absence of some or all of the other additives. The reaction temperature in this case is the same as the above conditions, and the reaction time is usually 0.1 to 10 hours, preferably 0.5 to 10 hours.
~ 8 hours. Furthermore, a sealant is obtained by mixing the remaining components with the prepolymer at the above-mentioned temperature and time conditions. The preferred reaction equivalent ratio (NCO / OH) at this time is 0.5 to 2.5.

Next, the multilayer transparent plate of the present invention will be described. As described above, in the present invention, the multilayer transparent plate refers to a plate obtained by joining at least two transparent plates with a sealant with a spacing member interposed between the transparent plates.

In the present invention, a glass plate is usually used as the transparent plate, but a part or all of the glass plate may be a transparent plastic plate depending on the application. Specific examples of the transparent plastic plate include acrylic resins such as polycarbonate and polymethyl methacrylate, ester resins such as polyvinyl chloride, polystyrene, proethylene terephthalate and polybutylene terephthalate, and polyurethane.

The spacing material (spacer) is used to maintain the spacing between the transparent plates, and is usually made of metal such as aluminum, plastic, rubber, or the like. A rigid material such as a metal is preferable in order to keep the interval between the transparent plates constant, but an elastic material such as rubber is preferable in terms of impact resistance and airtightness. A rigid member such as a metal may be used as the spacing member, and a composite member in which a rubber-like substance is bonded, fused, or applied to a portion in contact with the transparent plate may be used. When a rubber-like material is used for part or all of the spacing material, this may be referred to as a primary sealant.
In this case, a sealant that joins the transparent plate and the spacing material and shuts off the space between the outside air and the spacing material is called a secondary sealant.

As the sealant for joining the transparent plate and the spacing member, the above-described sealant of the present invention may be used to manufacture a multilayer transparent plate by a conventional method.

〔Example〕

 Next, the present invention will be described with reference to examples.

Production Example (1) Preparation of liquid polyisoprene having a hydroxyl group at a molecular chain terminal 200 g of isoprene was placed in a stainless steel pressure-resistant reaction vessel.
40 g of 20% hydrogen peroxide solution and 100 g of isopropanol
g, and the reaction was carried out under the conditions of a temperature of 120 ° C. and a reaction time of 2 hours. During the reaction, the pressure reached up to 8 kg / cm ² G. After the completion of the reaction, the reaction mixture was put into a separating funnel, 600 g of water was added thereto, and the mixture was shaken. After allowing to stand for 3 hours, an oil layer was separated. Solvents, monomers and low boiling components were removed from this oil layer by 2 mmHg,
Distillation was carried out at 100 ° C. for 2 hours to obtain a liquid polyisoprene having a hydroxyl group at a molecular chain terminal (yield: 66% by weight). Its number average molecular weight is 2240, hydroxyl content is 0.96 meq /
g, viscosity was 64 poise / 30 ° C., and bromine value was 220 g / 100 g.
At this time, the average number of hydroxyl groups per molecule is 2.15.
The results of structural analysis by ¹ H-NMR were as follows: trans-1,4 structure 57%, cis-1,4 structure 33%, cis-1,2 structure 6%, cis-3,4 structure 4%. .

(2) Preparation of hydride of liquid polyisoprene having a hydroxyl group at a molecular chain terminal 100 g of liquid polyisoprene having a hydroxyl group at a molecular chain terminal obtained in Production Example 1 (1), 5 g of a ruthenium carbon catalyst having a ruthenium content of 5% by weight Further, 100 g of cyclohexane was charged as a solvent, and a hydrogenation reaction was performed at 150 ° C. for 6 hours under a hydrogen pressure of 50 kg / cm ² G. After completion of the reaction, the catalyst was separated and removed from the reaction solution through a 0.45 μm membrane filter, and then the solvent was distilled off under the conditions of 2 mmHg, 110 ° C. and 2 hours. As a result, a hydride of liquid polyisoprene having a hydroxyl group at a molecular chain terminal was obtained. The number average molecular weight of this is 2310,
The hydroxyl group content was 0.94 meq / g, the viscosity was 402 poise / 30 ° C., and the bromine value was 1 g / 100 g. At this time, the average number of hydroxyl groups per molecule is 2.17.

Example 1 After the raw materials shown in Table 1 were manually kneaded, the mixture was passed twice through three paint mill rolls (hereinafter, referred to as main agent (a)).
I got

Isonate 143L (carbodiimide-modified MDI, manufactured by Mitsubishi Kasei Dow Co., Ltd., NCO content 29.0wt with respect to 100g of main ingredient (a)
%) And stirred at room temperature for 2 minutes.
Vacuum degassed for minutes. The obtained composition was tested according to the tensile adhesion test of JIS A5758, using an adherend as an aluminum plate or a glass plate.As a result, it was confirmed that the state of destruction was cohesive failure, and the composition was suitable as a sealant. I understood. In this test, the material causing interfacial fracture shows insufficient adhesion to the glass plate and the spacer member, and is difficult to use as a sealant. The reaction equivalent ratio (NCO / OH, molar ratio) at the time of blending the isocyanate compound (Isonate 143L) was 1.31 only for Poly bd R-45HT, and 0.976 for the entire hydroxyl group-containing compound. .

Example 2 After the raw materials shown in Table 2 were manually kneaded, the mixture was passed twice through three paint mill rolls (hereinafter, referred to as main agent (b)).
I got

3.44 g of the same isonate 143L used in Example 1 was added to 100 g of the base material (b), and a tensile adhesion test was conducted in the same manner as in Example 1. As a result, it was found that the failure state was cohesive failure. It was confirmed and found to be suitable as a sealant. In addition, isocyanate compounds (Isonate
143L) The reaction equivalent ratio (NCO / OH, molar ratio) at the time of compounding is
The value was 1.05 for Poly bd R-45HT alone, and 0.713 for the entire hydroxyl group-containing compound.

Example 3 After the raw materials shown in Table 3 were manually kneaded, the mixture was passed twice through three paint mill rolls (hereinafter, referred to as main agent (c)).
I got

Desmodur W (hydrogenated MDI,
Sumitomo Bayer Urethane Co., Ltd., NCO content 31.8wt%) 4.20
g was added, and a tensile adhesion test was performed in the same manner as in Example 1. As a result, it was confirmed that the state of destruction was cohesive failure, and it was found to be suitable as a sealant. In addition, the reaction equivalent ratio (NCO / OH, molar ratio) at the time of blending the isocyanate compound (Desmodur W) is 1.08 for only the hydride of the hydroxyl group-containing liquid polyisoprene obtained in Production Example, and is 1.08 for the hydroxyl group-containing liquid polyisoprene. 0.862 for the whole compound
Met.

Examples 4 to 6 and Comparative Examples 1 and 2 After the kneading of the sealant shown in Table 4 was carried out, it was cast on a Teflon plate so as to have a thickness of 1.5 mm, and the temperature and humidity were kept at 25 ° C. and 60% RH. Cured for 168 hours. The water vapor transmission coefficient of the obtained cured product was measured in accordance with DIN53122. 4th result
It is shown in the table.

The water vapor transmission coefficient indicates the performance of preventing the penetration of moisture into the space between the transparent plates of the sealant (moisture permeability). The lower this value is, the better the performance of preventing the penetration of moisture is. As is evident from Table 4, the sealant of the present invention has low moisture permeability, and has excellent moisture intrusion prevention performance.

Examples 7 to 9 and Comparative Examples 3 and 4 Using the sealants shown in Table 5, the 50% modulus was measured at -18 ° C and + 38 ° C in accordance with the tensile adhesion test of JIS A5758, and the following formula was used. Was used to calculate the modulus ratio. The results are shown in Table 5.

The sealant is stressed by the tightening of the window frame or the expansion and contraction of the transparent plate or the sealant itself due to the temperature. A large difference in stress due to temperature, that is, a large change in stress between day and night, summer and winter, etc., causes peeling between the transparent plate and the sealant. Therefore, it can be said that the closer the modulus ratio is to 1, the more excellent the durability is irrespective of the temperature change. As is clear from Table 5, it was found that the sealant of the present invention exhibited excellent durability irrespective of temperature change.

Examples 10 to 12 and Comparative Examples 5 and 6 The sealant shown in Table 6 had a diameter of 29.0 mm and a height of 12.7 mm.
And the following evaluation test was carried out.

(A) Compression set The sealant was cured at 25 ° C. and 60% RH for 168 hours to obtain a cured product. The cured product was subjected to a compression strain test in accordance with JIS K6301 (heat treatment condition: 70 ° C. for 22 hours). The results are shown in Table 6.

(B) Initial hardness development rate The sealant is cured at 25 ° C and 60% RH, and after 36 hours, 2
After 26 hours, the hardness was measured, and the initial hardness development rate was calculated according to the following equation in accordance with JIS K6301. Result 6
It is shown in the table.

As the value of the initial hardness development rate is larger, the multilayer board obtained in a shorter cycle can be sent to the next step, so that it can be said that the sealant has good workability. As is clear from Table 6, the sealant of the present invention was found to be a workable sealant.

〔The invention's effect〕

The sealant for a multilayer transparent plate of the present invention has excellent adhesive strength between the transparent plate and the spacer, low moisture permeability between the transparent plates, excellent impact resistance, and low temperature dependence of the elastic modulus. It is a sealant. In addition, the multilayer transparent plate of the present invention using the sealant does not invade moisture and can enhance the heat insulation and soundproofing effects.
It is suitably used for windows of high-rise buildings.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ identification code FI E06B 3/66 E06B 3/66 (58) Investigated field (Int.Cl. ⁶ , DB name) C09K 3/10 E06B 3/66 C08G 18/69 B32B 27/00

Claims (2)

(57) [Claims] 1. A sealant for a multilayer transparent plate for joining at least two transparent plates with a spacing material interposed between the transparent plates, wherein (A) at least 50% by weight or more has a number average molecular weight. A hydroxyl group-containing compound comprising a hydroxyl group-containing diene polymer and / or a hydroxide thereof of 500 to 9000; (B) a molar ratio of isocyanate groups to hydroxyl groups present in the hydroxyl group-containing compound (A) of 0.5 to 4;
(C) 30 to 300 parts by weight of filler based on 100 parts by weight of the hydroxyl group-containing compound (A) and (D) the hydroxyl group-containing compound (A)
A sealant for a multilayer transparent plate comprising 10 to 200 parts by weight of a viscosity reducing agent having a flash point of 40 ° C. or higher per 100 parts by weight. 2. A multilayer transparent plate comprising at least two transparent plates joined by a sealant according to claim 1, with a spacing member interposed between the transparent plates.