JP6547299B2 - Two-component curing type polyurethane sealant composition - Google Patents

Description

  The present invention relates to a two-part curable polyurethane-based sealant composition.

  Heretofore, a two-component curable polyurethane sealant composition has been used as a construction sealing material, which comprises a first liquid containing a urethane prepolymer and a second liquid containing a polyol. In this composition, it is preferable to reduce the weight in order to reduce the burden on the worker.

  Patent Document 1 discloses an invention in which a resin-based hollow body is blended with a second liquid in order to reduce the weight of a building sealing material. According to the invention described in Patent Document 1, it is disclosed that it is possible to provide a sealing material composition which is excellent in durability, can be reduced in specific gravity and has a small specific gravity, and is excellent in any of elastic recovery, modulus and elongation. There is.

  Further, in Patent Document 2, the microballoons having an average particle diameter of 10 to 100 μm are contained in an amount of 10% by weight or more and 17% by weight or less based on the room temperature curable resin, thereby maintaining pressure resistance. An invention is disclosed that can reduce the specific gravity sufficiently.

  However, if the proportion of the resin-based hollow body in the sealing material composition is excessively increased with priority given to weight reduction, the proportion of the resin component per unit volume decreases, which may affect physical properties and durability of the cured product. is there. In addition, when manufacturing the sealing material composition of patent document 1 and 2, the installation factor (blade shape, rotation speed) at the time of manufacture, the environmental factor (the sample temperature at the time of manufacture, moisture content, pH conditions) The possibility of the resin-based hollow body collapsing may be considered depending on When excessive collapse occurs in the resin-based hollow body, although the resin-based hollow body is adopted as the component of the second liquid, significant weight reduction is recognized as compared with the case where the resin-based hollow body is not adopted. It may not be possible. For this reason, in order to reduce the weight of the sealing material composition, there have been cases in which excessive trial and error have been required to study manufacturing conditions such as equipment factors during manufacturing and environmental factors.

  By the way, when installing in various joints etc. using a sealing material composition, a worker mixes the above-mentioned 1st liquid and the above-mentioned 2nd liquid first, caulking gun etc. the sealing material composition after mixing Suction into and fill in the equipment. Then, the operator operates the lever of the device to fill the sealant composition into the joint. Then, when the operator stops the operation of the lever, the filling of the sealant composition to the joint stops.

  However, when the sealant composition described in Patent Documents 1 and 2 is used, the sealant composition is discharged from the tip of a device such as a caulking gun even after the operator finishes the operation of the lever. Sometimes. This phenomenon is called springback among those skilled in the art, and is a problem in workability because it may contaminate the surroundings.

JP 2008-297473 A JP, 2011-68764, A

  The present invention has been made in view of the above circumstances, and while achieving physical properties and durability as a sealing material's original function, achieving weight reduction without adopting special manufacturing conditions It is an object of the present invention to provide a two-part curable polyurethane sealant composition capable of suppressing the phenomenon of springback even after the operator has finished operating the lever.

  The inventors of the present invention have conducted intensive studies to solve the problems described above, and it is assumed that the first liquid contains a urethane prepolymer, the second liquid contains a polyol, and the pressure resistance is predetermined. Containing a glass-based hollow body within the range and a resin-based hollow body having an average particle diameter within a predetermined range, and setting the mass ratio of the glass-based hollow body to the resin-based hollow body within a certain range Therefore, it is possible to achieve weight reduction without adopting special manufacturing conditions while having physical properties and durability as the original function of the sealing material, and to suppress occurrence of spring back after using a caulking gun. It has been found that the special effect is exerted, and the present invention has been completed. That is, the present invention relates to the following two-component curable polyurethane sealant composition.

  (1) The present invention comprises a first liquid containing a urethane prepolymer and a second liquid containing a polyol, wherein the second liquid is a glass-based hollow having a 90% by volume residual pressure resistance of 2.5 MPa or more And a resin-based hollow body having an average particle diameter of 10 μm to 50 μm, and a mass ratio of the glass-based hollow body to the resin-based hollow body (mass of glass-based hollow body / mass of resin-based hollow body) Is a two-component curable polyurethane-based sealing material composition having a value of 0.4 or more and 1.2 or less.

  (2) Moreover, in the present invention, the total content of the glass-based hollow body and the resin-based fine hollow body is 10% by mass or more and 20% by mass or less with respect to the mass of the second liquid. It is a two-component curing type polyurethane-based sealing material composition as described.

  (3) Moreover, this invention is a two-component curing type polyurethane-type sealing material composition as described in (1) or (2) whose said 90 volume% residual pressure resistance of the said glass-type hollow body is 5 Mpa or more. .

  According to the present invention, while having physical properties and durability as an original function of the sealing material, weight reduction can be achieved without adopting special manufacturing conditions, and generation of spring back after using a caulking gun is also suppressed. Provided is a two-part curable polyurethane-based sealing material composition.

  Hereinafter, although specific embodiments of the present invention will be described in detail, the present invention is not limited to the following embodiments in any way, and appropriate modifications may be made within the scope of the object of the present invention. can do.

<Two-component curable polyurethane-based sealant composition>
The two-component curable polyurethane-based sealing material composition (hereinafter, also referred to as "sealing material composition") of the present invention comprises a first liquid containing a urethane prepolymer and a second liquid containing a polyol.

[First liquid]
The first liquid mainly contains a urethane prepolymer. It is referred to by those skilled in the art as a base or main agent.

[Urethane prepolymer]
The type of urethane prepolymer is not particularly limited, and conventionally known ones can be used. For example, a reaction product obtained by reacting a polyol compound and a polyisocyanate compound such that the amount of isocyanate groups (NCO groups) is excessive with respect to hydroxyl groups (OH groups) can be used. In addition, the urethane prepolymer can contain 0.5 to 5% by mass of NCO groups at the molecular ends.

(Polyisocyanate compound)
The polyisocyanate compound used in the production of the urethane prepolymer is not particularly limited as long as it has two or more isocyanate groups in the molecule.

  Specific examples of the polyisocyanate compound include, for example, TDI (for example, 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI)), MDI (eg, For example, 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 1,4-phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, xylylene diisocyanate Aromatic polyisocyanates such as isocyanate (XDI), tetramethyl xylylene diisocyanate (TMXDI), tolidine diisocyanate (TODI), 1,5-naphthalene diisocyanate (NDI), triphenylmethane triisocyanate; Aliphatic polyisocyanates such as socyanate (HDI), trimethylhexamethylene diisocyanate (TMHDI), lysine diisocyanate, norbornane diisocyanate (NBDI); transcyclohexane-1,4-diisocyanate, isophorone diisocyanate (IPDI), bis (isocyanatomethyl) cyclohexane (H6XDI), alicyclic polyisocyanates such as dicyclohexylmethane diisocyanate (H12 MDI); carbodiimide-modified polyisocyanates thereof; isocyanurate-modified polyisocyanates thereof; and the like.

  Such polyisocyanate compounds can be used alone or in combination of two or more.

  Among these, tolylene diisocyanate (TDI) is preferable because the resulting urethane prepolymer has a low viscosity and the first liquid containing the urethane prepolymer can be easily handled.

(Polyol compound)
The polyol compound used in the production of the urethane prepolymer is not particularly limited as long as it has two or more hydroxy groups.

  As a polyol compound, polyether polyol, polyester polyol, other polyols, these mixed polyols etc. are mentioned, for example.

  Examples of polyether polyols include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, 1,1,1-trimethylolpropane, 1,2,5-hexanetriol, 1,3-butanediol, 1, A polyol obtained by adding at least one member selected from the group consisting of ethylene oxide, propylene oxide, butylene oxide and polyoxytetramethylene oxide to at least one member selected from the group consisting of 4-butanediol and pentaerythritol Can be mentioned. Specifically, polypropylene ether diol and polypropylene ether triol are suitably exemplified.

  Specifically, the polyester polyol is, for example, selected from the group consisting of ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, glycerin, 1,1,1-trimethylolpropane and other low molecular weight polyols. A condensation polymer of at least one selected from the group consisting of glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, dimer acid, other aliphatic carboxylic acids and oligomeric acids; Ring-opened polymers such as lactone and valerolactone; and the like.

  As other polyols, specifically, for example, polymer polyols, polycarbonate polyols; polybutadiene polyols; hydrogenated polybutadiene polyols; acrylic polyols; ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol, pentanediol, And low molecular weight polyols such as hexanediol.

  Such polyol compounds can be used alone or in combination of two or more. Of these, polypropylene ether diol and polypropylene ether triol are suitable for the viscosity of the curing agent, and the elongation and strength of the cured product comprising the sealing material composition of the present invention obtained using this curing agent It is preferable because it becomes suitable and the decrease in physical properties due to swelling after immersion in water is small.

  In the present invention, the combination of the polyol compound and the polyisocyanate compound in producing the urethane prepolymer is selected from the group consisting of tolylene diisocyanate (TDI), xylylene diisocyanate (XDI) and diphenylmethane diisocyanate (MDI). Preferred is a combination of at least one selected from polypropylene ether diol and / or polypropylene ether triol.

  Further, in the present invention, the amount of the polyisocyanate compound and the polyol compound at the time of producing the urethane prepolymer is preferably such that NCO group / OH group (equivalent ratio) is 1.2 to 2.5. It is more preferable to be 1.5 to 2.2. When the equivalent ratio is in such a range, the viscosity of the resulting urethane prepolymer becomes appropriate, and the residual amount of unreacted polyisocyanate compound in the urethane prepolymer can be reduced.

  In the present invention, the method for producing the urethane prepolymer is not particularly limited. For example, it can be produced by heating and stirring the polyol compound and the polyisocyanate compound in the above-described equivalent ratio at 50 to 130 ° C. In addition, if necessary, for example, urethane catalysts such as organic tin compounds, organic bismuth, and amines can be used.

  Such urethane prepolymers can be used alone or in combination of two or more.

[Polyaldimine]
In order to suppress foaming of the curing catalyst and maintain physical properties suitable as a sealing material, it is preferable that at least one of the first liquid and the second liquid further contain polyaldimine. It is known to use organometallic catalysts (lead catalysts, organotin compounds, organobismuth compounds) as curing catalysts. When at least one of the first liquid and the second liquid contains polyaldimine, it is possible to suppress the foaming phenomenon that may occur when curing is performed using the above-mentioned curing catalyst. When the second liquid contains a resin-based hollow body, the physical properties (durability, tensile properties, etc.) of the sealing material after mixing the first liquid and the second liquid and curing the composition are deteriorated. I tend to. However, by containing polyaldimine in at least one of the first liquid and the second liquid and making the second liquid contain the above-mentioned organometallic catalyst, the second liquid contains a resin-based hollow body Even if the specific gravity is reduced, it is possible to maintain appropriate physical properties as a sealing material.

  The polyaldimine is not particularly limited as long as it is a compound that produces an amine by hydrolysis, and a wide range of conventionally known polyaldimines can be used. However, since the storage stability is good, as the polyaldimine, aromatic Polyaldimines obtained by reacting an aldehyde and a polyamine are more preferable, and polyaldimines obtained by reacting an aromatic aldehyde and an alicyclic diamine are more preferable, and a poly represented by the following general formula (1) Aldimine is particularly preferred. These polyaldimines may be used alone or in combination of two or more.

In formula (1), R ¹ is an aryl group having a carbon number of 6 to 15, and examples thereof include a phenyl group and a substituted phenyl group substituted with one or more substituents. The substituent is preferably an alkyl group having 1 to 9 carbon atoms, an alkoxy group having 1 to 9 carbon atoms, and the like. The number of substituents of the above-mentioned aryl group is preferably 1 to 3. Specifically, R ¹ is preferably phenyl, methylphenyl, ethylphenyl, propylphenyl, butylphenyl, dimethylphenyl, methoxyphenyl, ethoxyphenyl, propoxyphenyl and the like. It can be mentioned. R ¹ may be the same or different in one molecule.

In the formula (1), R ² is a divalent or trivalent hydrocarbon group having 2 to 15 carbon atoms, a divalent or trivalent polyoxyalkylene group having a molecular weight of 70 to 6,000, and the amino residue of isophorone diamine Or an amino residue of an amine represented by the following general formula (2). In formulas (1) and (2), n represents 2 or 3.

In the formula (2), R ³ is a hydrocarbon group having 6 to 13 carbon atoms and consisting of a divalent or trivalent monocyclo ring, a bicyclo ring, or a tricyclo ring, and is a monocyclo ring, a bicyclo ring or a tricyclo ring The ring has preferably 5 to 12 carbon atoms. Furthermore, the cyclo ring may have a substituent. The substituent is preferably an alkyl group such as a methyl group, an ethyl group or a propyl group.

  The method for producing polyaldimine is not particularly limited, and it can be easily produced by a known method such as reacting an amine with an aldehyde. For example, the amine and the aldehyde are heated under acid catalyst in a solvent such as toluene, xylene, methylcyclohexane or butyl acetate to carry out azeotropic dehydration reaction to stop distillation of water in the water droplet separator. By continuing the reaction, polyaldimine is obtained. The mixing ratio of amine to aldehyde is suitably 1 to 2 equivalents of aldehyde per 1 equivalent of amine. The reaction is usually complete in a few hours. After completion of the reaction, the aldehyde, solvent and the like can be distilled off by a method such as reducing the pressure of the reaction mixture to obtain polyaldimine.

As the amine, polyamines are preferable, and for example, (a) aliphatic diamines such as ethylenediamine, 1,3-diaminopropane, tetramethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, decamethylenediamine, 4 4,4'-diaminodicyclohexylmethane, isophoronediamine, bisaminomethylcyclohexane, 2,5- or 2,6-diaminomethylbicyclo [2.2.1] heptane, diaminocyclohexane, 3 (4), 8 (9)- Alicyclic diamines such as bis (aminomethyl) -tricyclo [5.2.1.0 ^2.6 ] decane, diaminodiphenylmethane, diaminodiphenylether, xylylenediamine, phenylenediamine, 3,5-diethyltoluene-2,4 -Or 2,6-diam Polyoxyalkylene diamines obtained by converting the hydroxyl groups of polyoxyalkylene glycols obtained by addition polymerization of propylene oxide and / or ethylene oxide to aromatic diamines such as water, ethylene glycol, propylene glycol, etc. into amino groups And diamines, and (b) triamines such as 1,3,5-tris (aminomethyl) benzene, 1,3,5-tris (aminomethyl) cyclohexane, etc., glycerin, trimethylolpropane etc. with propylene oxide and / or ethylene. And triamines such as polyoxyalkylene triamines obtained by converting hydroxyl groups of polyoxyalkylene triols obtained by addition polymerization of oxides to amino groups and the like, and alicyclics such as alicyclic diamines or alicyclic triamines. Polyamines Preferably, in particular melting point 50 ° C. or lower melting polyamines are preferred.

  Examples of the aldehyde include benzaldehyde, o-tolualdehyde, m-tolualdehyde, p-tolualdehyde, 4-ethyl benzaldehyde, 4-propyl benzaldehyde, 4-butyl benzaldehyde, 2,4-dimethyl benzaldehyde, 2, 4, 5 -Trimethyl benzaldehyde, p-anisaldehyde, p-ethoxy benzaldehyde etc. is mentioned, An aromatic aldehyde is suitable.

Although the blend ratio of polyaldimine is not specifically limited, It is preferable to mix | blend 0.5-10 mass parts with respect to 100 mass parts of urethane prepolymers, and it is more preferable to mix | blend 2-5 mass parts. In particular, the equivalent ratio (NCO / NH ₂ ) of the isocyanate group contained in the urethane prepolymer to the amino group generated by hydrolysis of polyaldimine is preferably 1.4 to 28, and 2.8 to 7.0. It is more preferable that Polyaldimine may be used alone or in combination of two or more.

  The polyaldimine may be contained in either the first solution or the second solution, but in consideration of the hydrolyzability of the polyaldimine, the polyaldimine is preferably contained in the first solution.

[Second liquid]
The second liquid mainly contains a polyol. The second liquid contains various components such as an antioxidant, a plasticizer and the like in addition to the polyol, but is referred to as a curing agent by those skilled in the art.

[Polyol]
The second liquid mainly contains a polyol. As the polyol, polyether polyols such as polypropylene polyol (PPG) and polyethylene polyol (PEG), and the same polyols as those used as raw materials of the above-mentioned urethane prepolymer can be used. Among them, even in a relatively low temperature range (5 ° C. or less), the polyol is preferably a polyether polyol because the viscosity of the composition can be lowered (the workability is good), and a polypropylene polyol is preferred. More preferably it is (PPG). The number average molecular weight of such a polyol is preferably 400 to 12,000, and particularly 3,000 to 7,000, because well-balanced physical properties can be obtained.

  The polyols may be used alone or in combination of two or more.

[Glass based hollow body]
The second liquid contains a glass-based hollow body having a 90% by volume residual pressure resistance of 2.5 MPa or more. The glass-based hollow body is one in which the outer shell of the hollow sphere is made of glass. When the second liquid contains the glass-based hollow body, the resin-based hollow body similarly contained in the second liquid can be prevented from being crushed by an operation such as stirring at the time of producing the sealing material composition. The 90% by volume residual compressive strength of the glass-based hollow body is sufficient if it is 2.5 MPa or more, but in order to effectively suppress the collapse of the resin-based hollow body, it is preferably 5 MPa or more, and it is 20 MPa or more Is more preferable, and 25 MPa or more is more preferable.

The true density of the hollow glass body is preferably 0.2 g / cm ³ or more, and more preferably 0.3 g / cm ³ or more in order to effectively suppress the collapse of the resin-based hollow body.

  In the present embodiment, “90% by volume residual compressive strength” refers to a pressure value obtained by measurement using glycerol in accordance with ASTM D3102-78 (1982 edition). The specific measurement method will be described below. First, a predetermined amount of a glass-based hollow body is mixed with glycerol, and the one sealed without air is used as a measurement sample, and the measurement sample is set in a test chamber. Then, while gradually pressing, the volume change of the glass-based hollow body in the measurement sample is observed, and the pressure when the remaining volume of the glass-based hollow body in the measurement sample is 90% by volume (at 10% by volume breakage) taking measurement. The pressure obtained from this is referred to as “90% by volume residual pressure resistance”.

The glass constituting the outer shell of the hollow glass body is not particularly limited. For example, the main component is silicon dioxide (SiO ₂ ), sodium oxide (Na ₂ O), magnesium oxide (MgO), calcium oxide (CaO), boron oxide (B ₂ O ₅ ), phosphorus oxide (P ₂ O ₅ ) Etc. may be common glass etc. which have as a secondary component.

  The glass-based hollow body may be contained in the first liquid in addition to the second liquid, but in consideration of the storage stability of the first liquid, the glass-based hollow body should be contained only in the second liquid. Is preferred.

[Resin hollow body]
The second liquid contains a resin-based hollow body having an average particle diameter of 10 μm to 50 μm, preferably 10 μm to 40 μm. In the resin-based hollow body, the outer shell of the hollow sphere is made of resin. For example, a thermally expandable resin-based hollow body obtained by encapsulating a liquid in a resin-based hollow body and heating it to expand the resin-based hollow body to be an outer shell and vaporizing the liquid inside is It can be mentioned.

  As a material which comprises the outer shell of a resin type hollow body, a phenol resin, a urea resin, a polystyrene-type resin, polyvinylidene chloride, a thermoplastic resin etc. are mentioned, for example. Among these, at least one selected from the group consisting of phenol resin, urea resin, polystyrene, polyvinylidene chloride and thermoplastic resin is preferable.

  Specific examples of the thermoplastic resin constituting the outer shell of the thermoplastic resin hollow body include vinyl chloride, vinylidene chloride; acrylonitrile, methacrylonitrile; acrylate compounds such as benzyl acrylate and norbornane acrylate; methyl methacrylate And methacrylate compounds such as norbornane methacrylate and trimethylolpropane trimethacrylate; styrenic monomers; vinyl acetate; butadiene; butadiene; vinyl pyridine; homopolymers of chloroprene; copolymers thereof, and the like.

  Among these, from the viewpoint of weatherability and heat resistance, acrylonitrile copolymer (for example, copolymer of acrylonitrile and methacrylonitrile, copolymer of acrylonitrile and copolymerizable vinyl monomers such as butadiene and styrene, which are copolymerizable with acrylonitrile) Preferred is a vinylidene chloride polymer).

  On the other hand, as the liquid to be contained in the resin-based hollow body, for example, hydrocarbons such as n-pentane, isopentane, neopentane, butane, isobutane, hexane and petroleum ether; methyl chloride, methylene chloride, dichloroethylene, trichloroethane, trichloroethane Chlorinated hydrocarbons such as ethylene can be mentioned.

  In order to improve the handling property when producing the second liquid, the resin-based hollow body is preferably coated with an inorganic filler. In this case, the type of the inorganic filler is not particularly limited, and specific examples thereof include calcium carbonate, titanium oxide, silicon oxide, talc, clay, carbon black and the like. Among them, at least one selected from the group consisting of calcium carbonate, titanium oxide, silicon oxide, talc, clay and carbon black is preferable from the viewpoint of excellent coating of the resin-based hollow body. In addition, an inorganic filler can be used individually or in combination of 2 or more types, respectively. Moreover, the method of coating a resin-type hollow body with an inorganic filler is not specifically limited, It can coat by a conventionally well-known method.

  The resin-based hollow body may be contained in the first liquid besides the second liquid, but in consideration of the storage stability of the first liquid, the resin-based hollow body should be contained only in the second liquid. Is preferred.

  The average particle diameter of the resin-based hollow body is 10 μm or more and 50 μm or less, and preferably 10 μm or more and 40 μm or less. If the average particle size is less than 10 μm, the weight reduction of the sealing material composition may not be sufficiently secured, which is not preferable. In addition, if the average particle size exceeds 50 μm, springback, that is, even after the operator has finished operating the caulking gun, there is a possibility that the phenomenon that the sealant composition is discharged from the tip can not be suppressed. Unfavorable because there is.

  The method for producing the resin-based hollow body is not particularly limited, and can be produced by a conventionally known method.

  In the sealing material composition of the present invention, while maintaining the physical properties and durability as the original function of the sealing material, regardless of the shape of the stirring blade for mixing the raw materials, extrusion conditions of the raw materials, etc. In order to avoid crushing, the mass ratio of the glass-based hollow body to the resin-based hollow body (mass of the glass-based hollow body / mass of the resin-based hollow body) is set to 0.4 or more and 1.2 or less. Furthermore, in order to lower the viscosity of the sealing material composition and to more reliably avoid the phenomenon of spring back, the mass ratio of the glass-based hollow body to the resin-based hollow body is more preferably 0.4 or more and 0.8 or less . When the mass ratio of the glass-based hollow body to the resin-based hollow body is too small, the collapse resistance of the resin-based hollow body is not sufficient, and in order to avoid the collapse of the resin-based hollow body, of the stirring blade for mixing the raw materials It is not preferable because optimization of the shape and extrusion conditions of raw materials may be required. When the mass ratio of the glass-based hollow body to the resin-based hollow body is too large, it is not preferable because the durability and tensile properties as the original function of the sealing material may not be sufficiently secured.

  Further, in the sealing material composition of the present invention, the total content of the glass-based hollow body and the resin-based fine hollow body is preferably 10% by mass or more and 20% by mass or less with respect to the mass of the entire second liquid. The total content of the glass-based hollow body and the resin-based fine hollow body is more preferably 10% by mass or more and 15% by mass or less with respect to the total mass of the second liquid. If the total content of the glass-based hollow body and the resin-based fine hollow body is too small, the second liquid can not be reduced in specific gravity, which is not preferable. When the total content of the glass-based hollow body and the resin-based fine hollow body of the second liquid is too large, the viscosity of the second liquid is excessively high, which is not preferable in that the workability is lowered.

[Surface-treated calcium carbonate]
The second solution preferably contains surface-treated calcium carbonate. The surface-treated calcium carbonate functions as a thixotropic agent, so that the second liquid contains the surface-treated calcium carbonate, thereby causing springback, that is, even after the operator has finished operating the caulking gun, It is possible to suppress the phenomenon that the sealant composition is discharged from that point on.

  In surface-treated calcium carbonate, the surface treatment agent to be used is not particularly limited, and known surface treatment agents can be widely used. Examples of the surface treatment agent include higher fatty acid compounds, higher fatty acid ester compounds, resin acid compounds, aromatic carboxylic acid esters, anionic surfactants, cationic surfactants, and nonionic surfactants. And paraffin, titanate coupling agents and silane coupling agents. These surface treatment agents may be used alone or in combination of two or more.

  As surface-treated calcium carbonate, known surface-treated calcium carbonate can be widely used, and there is no particular limitation. For example, Vigot 15 (manufactured by Shiroishi Calcium Co., Ltd., light calcium carbonate surface-treated with a fatty acid) Surface-treated light calcium carbonate such as primary particle size 0.15 μm); Vigot 10 (manufactured by Shiroishi Calcium Co., Ltd., colloidal calcium carbonate surface-treated with fatty acid, primary particle size 0.10 μm), white matted flower CCR-B (white stone Calcium Co., Ltd., colloidal calcium carbonate surface-treated with fatty acid, primary particle diameter 0.08 μm, Calfine N-350 (Maruo Calcium Co., Ltd., product, colloidal calcium carbonate surface-treated with fatty acid, primary particle size 0.04 μm), Sealets 200 (manufactured by Maruo Calcium Co., Ltd., fatty acid ester) Surface-treated colloidal calcium carbonate, primary particle size 0.05 μm), Sealets 500 (manufactured by Maruo Calcium Co., Ltd., colloidal calcium carbonate surface-treated with fatty acid ester, primary particle size 0.05 μm), Sealets 700 (maruo calcium) Co., Ltd., colloidal calcium carbonate surface-treated with fatty acid ester, primary particle diameter 0.05 μm, Hakuka Hana DD (manufactured by Shiroishi Calcium Co., Ltd.), colloidal calcium carbonate surface-treated with resin acid, primary particle diameter 0. 05 μm), Calex 300 (manufactured by Maruo Calcium Co., Ltd., colloidal calcium carbonate surface-treated with fatty acid, primary particle diameter 0.05 μm), Neorite SS (Takehara Chemical Industry Co., Ltd., manufactured by fatty acid, colloidal Calcium carbonate, average particle size 0.04 μm), Neolite GP- 0 (Takehara Chemical Industry Co., Ltd. product, colloidal calcium carbonate surface-treated with resin acid, average particle diameter 0.03 μm), Calcey's P (Kanjima Chemical Industry Co., Ltd. product, colloidal calcium carbonate surface-treated with fatty acid, Surface-treated colloidal calcium carbonate having an average particle size of 0.15 μm, etc .; Lighton A-5 (manufactured by Bihoku Kogyo Kogyo Co., Ltd., heavy calcium carbonate surface-treated with fatty acid, average particle size of 3.6 μm), MC coated P1 (Maruo Calcium Co., Ltd. product, heavy calcium carbonate surface-treated with paraffin, primary particle diameter 3.3 μm), AFF-95 (Fimatech Co., Ltd., heavy calcium carbonate surface coated with cationic polymer, Primary particle size 0.9 μm), AFF-Z (manufactured by Fimatech Co., Ltd., ground calcium carbonate surfaced with cationic polymer and antistatic agent, Surface treated calcium carbonate of the following particle size 1.0 .mu.m), and the like. Among these, calcium carbonate surface-treated with a fatty acid ester is more preferable in that the storage stability of the curable composition is good.

  The content of the surface-treated calcium carbonate is preferably 30% by mass or more, and more preferably 40% by mass or more, based on the total mass of the second liquid. If the content of the surface-treated calcium carbonate is too low, sufficient thixotropy may not be imparted, and as a result, spring back may occur.

  Further, the content of the surface-treated calcium carbonate with respect to calcium carbonate is preferably 80% by mass or more of calcium carbonate, and more preferably 90% by mass or more. If the ratio of surface-treated calcium carbonate to calcium carbonate is too low, thixotropy may not be sufficiently imparted, resulting in spring back.

[Urethane plasticizers]
Although not an essential component, the second liquid may contain a urethane plasticizer, that is, a reaction product of a polyalkylene ether monool and hexamethylene diisocyanate in order to keep the viscosity low and improve the workability of the composition. preferable.

  The production method of the polyalkylene ether monool is not particularly limited, and can be obtained by a known production method. For example, ethylene oxide, propylene oxide, butylene oxide can be obtained by using a compound having a hydroxyl group as one active hydrogen group at the molecular terminal. It is possible to use one obtained by polymerizing or copolymerizing alkylene oxides such as styrene oxide alone or a mixture of these polymers.

  Examples of the compound having a hydroxyl group as one active hydrogen group at the molecular terminal include aliphatic monoalcohols such as methanol, ethanol, propanol, butanol, pentanol, hexanol and octanol; cyclopentanol, dimethylcyclohexanol and the like Aliphatic monoalcohols such as benzyl alcohol; aromatic (phenolic) monoalcohols such as phenol and cresol; and monoalcohols.

  These polyalkylene ether monools may be used alone or in combination of two or more. The OH number of the polyalkylene ether monool is preferably 5.5 to 281.0 [mg KOH / g], more preferably 11.0 to 140.3 [mg KOH / g], and 24.0 to 125.0 [mg KOH]. Is more preferable. As the polyalkylene ether monool, polyoxypropylene monool (including one containing a polyoxyethylene unit) is preferable.

  The reaction of the polyalkylene ether monool with hexamethylene diisocyanate is preferably carried out under the reaction conditions of 40 ° C to 100 ° C. The reaction is preferably such that the NCO / OH equivalent ratio is 1.1 / 1.0 to 1.0 / 1.1. By reacting the hydroxyl group of the polyalkylene ether monool with the isocyanate group, not only the hydroxyl group is blocked but also substantially all isocyanate groups are blocked. It is suitable that content of the isocyanate group which remains in a urethane type plasticizer is 0.1 mass% or less from a point of suppressing foaming. In order to shorten the reaction time of the polyalkylene ether monool mentioned above and hexamethylene diisocyanate, it is suitable to use catalysts, such as a tertiary amine, a tin catalyst, a bismuth catalyst.

  The viscosity of the urethane plasticizer is preferably 10,000 mPa · s or less at 25 ° C., and more preferably 500 mPa · s or more and 7,000 mPa · s or less.

  The proportion of the urethane plasticizer is not particularly limited, but it is preferably 1 to 50 parts by mass, more preferably 5 to 20 parts by mass, with respect to 100 parts by mass of the urethane prepolymer contained in the first liquid. preferable.

  The urethane plasticizer may be used alone or in combination of two or more.

[Other components (additives)]
The sealing material composition of the present invention can contain an additive in addition to the urethane prepolymer, the polyol, the glass-based hollow body and the resin-based hollow body, as long as the object of the present invention is not impaired. As an additive, a reinforcing agent, a curing catalyst, a plasticizer, a dispersing agent, a solvent, an antioxidant, an antiaging agent, a pigment etc. are mentioned, for example. The additive may be added to the first solution or may be added to the second solution.

(Reinforcement agent)
The reinforcing agent is not particularly limited as long as it can reinforce the cured product physical properties (e.g., elongation, tensile strength, etc.) of the obtained cured product of the sealing material composition of the present invention, and conventionally known materials may be used. Can.

  Examples of the reinforcing agent include titanium oxide, silicon oxide, talc, clay, quick lime, kaolin, zeolite, diatomaceous earth, finely powdered silica, hydrophobic silica, carbon black and the like. Among these, titanium oxide, hydrophobic silica and carbon black are preferable from the viewpoint of wettability with polypropylene ether hydroxide and a plasticizer. In addition, a reinforcing agent can be used individually or in combination of 2 or more types, respectively.

  The content of the reinforcing agent is excellent with respect to the breaking elongation of the cured product comprising the sealing material composition of the present invention obtained, and from the viewpoint of compensating for the breaking strength, 100 parts by mass of the urethane prepolymer contained in the first liquid, The amount is preferably 40 to 160 parts by mass, and more preferably 50 to 150 parts by mass.

(Curing catalyst)
As a curing catalyst, an organometallic catalyst is mentioned, for example. Organometallic catalysts, for example, lead catalysts such as lead octenoate and lead octylate; organozinc compounds such as zinc octylate; organotin compounds such as dibutyltin dilaurate and dioctyltin laurate; calcium octylate, Organic calcium compounds such as calcium neodecanoate; organic barium compounds; organic bismuth compounds; and the like can be mentioned. The curing catalysts can be used alone or in combination of two or more.

  It is preferable that the usage-amount of a curing catalyst is 0.2-5 mass% with respect to the mass of the 2nd whole liquid. The curing catalyst may be added to the curing agent together with the polypropylene ether hydroxide, or may be added when mixing the main agent and the curing agent.

(Plasticizer)
As a plasticizer, for example, diisononyl adipate (DINA), diisononyl phthalate (DINP), dioctyl phthalate (DOP), dibutyl phthalate (DBP), dilauryl phthalate (DLP), dibutyl benzyl phthalate (BBP), dioctyl adipate (DOA) ), Diisodecyl adipate (DIDA), trioctyl phosphate (TOP), tris (chloroethyl) phosphate (TCEP), tris (dichloropropyl) phosphate (TDCPP), propylene glycol adipate polyester, butylene glycol adipate polyester, terminal Esterified polyfunctional polyethers, acetic acid esters of polyoxyalkylene monoalkyl ethers, polyethylene glycol dibenzoate and the like can be mentioned. The plasticizers can be used alone or in combination of two or more.

  The amount of the plasticizer used is preferably 20 parts by mass or less with respect to 100 parts by mass of the urethane prepolymer.

(Dispersant)
The dispersant is not particularly limited as long as the solid can be dispersed in the liquid. The amount of the dispersant to be used is preferably 0.01 to 5% by mass, and more preferably 0.05 to 5% by mass, based on the whole of the second liquid.

(solvent)
As a solvent, for example, hydrocarbon compounds such as hexane and toluene; halogenated hydrocarbon compounds such as tetrachloromethane; ketones such as acetone and methyl ethyl ketone; ethers such as diethyl ether and tetrahydrofuran; esters such as ethyl acetate Mineral spirits; etc.

(Antioxidant)
Specific examples of the antioxidant include butylhydroxytoluene (BHT), butylhydroxytoluene anisole (BHA), diphenylamine, phenylenediamine, triphenyl phosphite and the like.

(Pigment)
Pigments are roughly classified into inorganic pigments and organic pigments. Specific examples of the inorganic pigment include, for example, titanium dioxide, carbon black, zinc oxide, ultramarine blue, metal oxides such as bengal; sulfide of lithopone, lead, cadmium, iron, cobalt, aluminum, and hydrochlorides thereof Or these sulfates etc. are mentioned. Specifically as an organic pigment, an azo pigment, a copper phthalocyanine pigment, etc. are mentioned, for example.

[Theoretical specific gravity]
In order to ensure a low specific gravity of the sealing material composition after curing, it is preferable to set the theoretical specific gravity of the second liquid to 1.00 g / cm ³ or less. If the theoretical specific gravity is 1.00 g / cm ³ or less, lowering of the specific gravity of the sealing material composition after curing is sufficiently achieved, and it can be said that the processability and cost are excellent. In addition, the sealing material composition according to the present embodiment achieves low viscosity by suppressing the mass ratio of the glass-based hollow body to the resin-based hollow body to be within a predetermined range, thereby suppressing the occurrence of the phenomenon of spring back. ing. In the present specification, “theoretical specific gravity” is obtained by adding the product of the specific gravity of each component of the composition (hereinafter referred to as “true specific gravity”) and the composition ratio in terms of volume. Mean the value of

Thixotropy Index of Second Solution
In the present invention, in order to suppress the phenomenon of spring back, it is preferable to keep the thixotropy index within a certain range. In the present invention, the thixotropy index is the ratio of the viscosity (Pa · s) of the object when measured at a rotational speed of 1 rpm and 10 rpm at 23 ° C. and 50% relative humidity using No. 7 rotor of BS type viscometer The thixotropy index [(the viscosity of the object at 1 rpm) / (the viscosity of the object at 10 rpm)] is calculated. In the present invention, the thixotropy index of the second liquid is not particularly limited, but is preferably 2.9 or more, and more preferably 3.1 or more. If the thixotropy index is too low, a springback phenomenon may occur after using the sealing material composition obtained by mixing the first liquid and the second liquid, which is not preferable.

[Mixing of the first liquid and the second liquid]
The mixing ratio of the first liquid and the second liquid is not particularly limited, but the urethane prepolymer with respect to the total equivalent of the amino group generated by hydrolysis of the polyaldimine and the hydroxyl group of the polyol in the second liquid. it is equivalent ratio of isocyanate groups (R _{value) [NCO / (OH + NH} 2)] contained in, preferably from 0.5 to 2.0, more preferably 0.7 to 1.5.

[Thixotropy index of mixed solution]
In addition, the equivalent ratio (R value) of the isocyanate group contained in the urethane prepolymer to the total equivalent of the amino group generated by hydrolysis of the polyaldimine and the hydroxyl group of the polyol in the second liquid [NCO / (OH + NH ₂ ) The thixotropy index of the mixture obtained by mixing the first solution and the second solution so as to obtain 1.08 and stirring for 15 minutes using a light-weight mixer (Mixta Kogyo Co., Ltd.) is 5.0 or more Is preferable, and 5.5 or more is more preferable.

  Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these descriptions.

<Preparation of Two-component Curing Type Polyurethane Sealing Material Composition>

[Preparation of first solution]
In Table 1, the compounding quantity of each compounding substance is shown by the mass part.
748 parts by mass of 2,4-tolylene diisocyanate, 2600 parts by mass of polyoxypropylene glycol (OH number 55.6 mg KOH / g), 1802 parts by mass of polyoxypropylene triol (OH number 56.1 mg KOH / g) at 80 ° C. The reaction was carried out for 7 hours to obtain an isocyanate group-terminated urethane prepolymer. The terminal NCO group was 3.49% by mass, and the viscosity was 7,500 mPa · s / 25 ° C.

  Then, 2.5 parts by mass of polyaldimine was mixed with 100 parts by mass of the above-mentioned urethane prepolymer to prepare a first solution.

[Preparation of second solution]
In Table 1, the compounding quantity of each compounding substance is shown by a mass part, and various materials are as follows.
* 1 Polypropylene ether triol (Product name: Actocol T-5000, number average molecular weight: 5000, manufactured by Mitsui Chemicals, Inc.)
* 2 Polypropylene ether diol (Product name: Actocol D-3000, number average molecular weight: 3000, Mitsui Chemicals, Inc.)
※ 3 Average particle size: 20 to 40 μm (Product name: MFL-SEVEN, average particle size is 20 to 40 μm, hollow resin body with a true specific gravity of 0.14 ± 0.03 g / cm ³ ), Matsumoto Yushi Pharmaceutical Co., Ltd. Made)
※ 4 Average particle diameter 60-70 μm (Product name: MFL-100 MCA, average particle diameter 60-70 μm, hollow resin body with true specific gravity 0.12 ± 0.02 g / cm ³ ), Matsumoto Yushi Pharmaceutical Co., Ltd. Made)
※ 5 compressive strength 28MPa (product name: S38, a compressive strength 28MPa, glass-based hollow body true specific gravity of 0.38g / cm ^3, manufactured by 3M Japan Co., Ltd.)
※ 6 compressive strength 2.8MPa (product name: S22, a compression strength 2.8MPa, glass-based hollow body true specific gravity of 0.22g / cm ^3, manufactured by 3M Japan Co., Ltd.)
* 7 Fatty acid-treated calcium carbonate (Product name: Calfine 200, manufactured by Maruo Calcium Co., Ltd.)
※ 8 Heavy calcium carbonate (Product name: Super # 1500, manufactured by Maruo Calcium Co., Ltd.)
※ 9 Reaction of 200 g of polyalkylene ether monool (product name: Actocol EH-25, polyoxypropylene monool, Mitsui Chemicals, Inc.) and 9.05 g of hexamethylene diisocyanate (product name: HDI, manufactured by Nippon Polyurethane Industry) Then, a urethane plasticizer was synthesized. The viscosity of the urethane plasticizer was 6,400 mPa · s / 25 ° C., and the number average molecular weight was 4,268.
* 10 Titanium oxide (Product name: Taipek R 820, manufactured by Ishihara Sangyo Co., Ltd.)
※ 11 Antioxidant (Product name: Irganox 1010, Hindered phenolic antioxidant, manufactured by BASF)
* 12 Curing catalyst (Product name: Pukat 25, bismuth octylate, manufactured by Nippon Chemical Industrial Co., Ltd.)
※ 13 Plasticizer (Product name: TXIB, 2,2,4-trimethyl-1,3-pentanediol diisobutyrate, manufactured by Eastman Chemical Co., Ltd.)
※ 14 Petroleum hydrocarbon (Product name: Exsol D-80, Exxon Mobil Chemical Co., Ltd.)
※ 15 Octylic acid (made by Toyo Gosei Co., Ltd.)

  The petroleum hydrocarbon and all materials other than octylic acid were charged in a planetary mixer at a mass ratio shown in Table 1 and stirred and mixed at 90 ° C. for 1 hour under reduced pressure to dehydrate the composition. Then, after cooling to 20 ° C., petroleum hydrocarbon and octylic acid were added, and vacuum mixing was further performed for 10 minutes to obtain a second liquid.

[Mixing of the first liquid and the second liquid]
The equivalent ratio (R value) [NCO / (OH + NH ₂ )] of the isocyanate group contained in the urethane prepolymer with respect to the total equivalent of the amino group generated by hydrolysis of the polyaldimine and the hydroxyl group of the polyol in the second liquid The first solution and the second solution were mixed so as to be 1.08, and stirred for 15 minutes using a lightweight mixer (manufactured by Mixta Kogyo Co., Ltd.). By doing this, sealing material compositions according to Examples and Comparative Examples were obtained. The weight ratio of the first solution to the second solution was as described in Table 1.

<Evaluation>
First, regarding the second liquid according to the examples and comparative examples, the mass of the glass-based hollow body / the mass of the resin-based hollow body, the theoretical specific gravity, the actual specific gravity, the actual specific gravity / theoretical specific gravity, the collapse resistance, the viscosity, and the thixotropy index are described below. It evaluated by the method shown. Moreover, about the sealing material composition which concerns on an Example and a comparative example, a viscosity, a thixotropy index, durability, tensile characteristics, and springback property were evaluated by the method shown below.

[Evaluation of second solution]
(1) Mass of glass-based hollow body / mass of resin-based hollow body For the second liquid, the mass ratio of glass-based hollow body to resin-based hollow body (mass of glass-based hollow body / mass of resin-based hollow body) was calculated. did. The results are shown in Table 1.

(2) Theoretical Specific Gravity of Second Liquid The theoretical specific gravity of the second liquid was determined by adding the product of the true specific gravity of each component constituting the second liquid and the composition ratio in terms of volume. The results are shown in Table 1.

(3) Actual specific gravity The actual specific gravity of the 2nd liquid manufactured in the actual manufacturing process was measured based on JISK6833-1.5.2.1 "specific gravity cup method." The results are shown in Table 1.

(4) Actual Specific Gravity / Theoretical Specific Gravity For the second liquid, the ratio of the actual specific gravity to the theoretical specific gravity (actual specific gravity / theoretical specific gravity) was calculated. The results are shown in Table 1. The closer the ratio of the actual specific gravity to the theoretical specific gravity is to 1.00, the smaller the collapse of the second liquid after production.

(5) Crush resistance Crush resistance was evaluated based on the above-mentioned value of actual specific gravity / theoretical specific gravity. Specifically, those having an actual specific gravity / theoretical specific gravity value of less than 1.15 are indicated by “◎”, those having a value of 1.15 or more and less than 1.18 are indicated by “○”, those having 1.18 or more are indicated It evaluated as x ". The results are shown in Table 1.

(6) Viscosity (Pa · s)
The viscosity (Pa · s) measured at a rotational speed of 1 rpm and 10 rpm at 23 ° C. and 50% relative humidity was measured for the second liquid and the sealant composition using a No. 7 rotor of a BS type viscometer. The results for the second solution are shown in Table 1, and the results for the sealant composition are shown in Table 1.

(7) Thixotropy Index Thixotropy Index [(viscosity at 1 rpm) / (viscosity at 10 rpm)] was calculated from the ratio of viscosity (Pa · s) measured at rotational speeds of 1 rpm and 10 rpm. The results for the second solution are shown in Table 1, and the results for the sealant composition are shown in Table 1. In the present specification, the thixotropy index of the sealing material composition is the isocyanate group contained in the urethane prepolymer relative to the total equivalent of the amino group generated by hydrolysis of the polyaldimine and the hydroxyl group of the polyol in the second liquid. The first solution and the second solution are mixed so that the equivalent ratio (R value) of [NCO / (OH + NH ₂ )] is 1.08, and stirred for 15 minutes using a lightweight mixer (Mixta Kogyo Co., Ltd.) Calculated from the ratio of the viscosity (Pa · s) of the mixture measured at a rotational speed of 1 rpm and 10 rpm at 23 ° C. and 50% relative humidity using a No. 7 rotor of a BS type viscometer for the mixed mixture Let the thixotropy index of the mixture [(the viscosity of the mixture at 1 rpm) / (the viscosity of the mixture at 10 rpm)].

[Evaluation of sealing material composition]
(1) Durability The two-component curable polyurethane-based sealing material composition thus obtained was subjected to the test defined in JIS A 5758: 2010 to evaluate the durability category 8020. The results are shown in Table 1. Clear abnormalities such as dissolution, swelling, cracking, peeling from the adherend, etc. of the test body were visually confirmed, and those without these abnormalities were evaluated as "○" as those excellent in durability, and these abnormalities were evaluated. Those that had been evaluated as "poor" were evaluated as "poor" in durability.

(2) Springback property First, a nozzle having an inner diameter of about 8 mm was attached to a 320 ml paper tube cartridge, and the sealant composition according to the example and the comparative example was filled. Subsequently, about 100 g of the above-mentioned sealant composition was discharged using a cartridge gun. Subsequently, the paper tube cartridge was removed from the cartridge gun, and the above-described cartridge gun was placed on a desk so that the nozzle of the paper tube cartridge was directed upward. Then, after one hour since standing, the amount of the composition discharged from the tip of the nozzle (naturally) was measured. The composition having a discharge amount of 1 g or less was evaluated as "o", and the composition exceeding 1 g was evaluated as "x". The results are shown in Table 1.

(3) Tensile properties Each of the obtained two-component curable polyurethane-based sealing material compositions was evaluated according to “5.3 Tensile property test” defined in “Testing method of sealing material for construction” of JIS A1439: 2010. % Tensile stress at elongation M50 (N / mm ² ), tensile stress at 100% elongation M100 (N / mm ² ), tensile stress at break TB (N / mm ² ), elongation at break EB (% Was measured. An anodic aluminum oxide substrate was used as an adherend, and curing was performed for 28 days under conditions of 23 ° C. and 50% relative humidity. Moreover, the test was performed under conditions of 23 ° C. and 50% relative humidity. The results are shown in Table 1.

In Table 1, M50, M100, TB and EB are as follows.
M50: Tensile stress at 50% elongation (N / mm ² )
M100: Tensile stress at 100% elongation (N / mm ² )
TB: tensile stress at failure (N / mm ² )
EB: Elongation at break (%)

  The sealing material composition of the example contains a urethane prepolymer as the first liquid, a polyol as the second liquid, a glass-based hollow body having a 90% by volume residual pressure resistance of 2.5 MPa or more, and an average particle diameter of 10 μm. And a resin-based hollow body having a diameter of 50 μm or less. In the second liquid, the mass ratio of the glass-based hollow body to the resin-based hollow body is 0.4 or more and 1.2 or less. As a result, the sealing material composition obtained by mixing and curing the first liquid and the second liquid has a physical property and durability as an original function of the sealing material, and is lightweight with the resin-based hollow body as a component. It was also confirmed that the collapse of the resin-based hollow body can be suppressed even in the case of achieving Moreover, it was also confirmed that it contributes to suppression of the spring back phenomenon after use of a caulking gun by using the sealing material composition of an Example.

  On the other hand, in Comparative Example 1 and Comparative Example 2, it was confirmed that the collapse resistance of the resin-based hollow body was not sufficient. As a result, although the resin-based hollow body is adopted as the component of the second liquid, the resin-based hollow body is crushed depending on the shape of the stirring blade for mixing the raw materials, the extrusion conditions of the raw materials, etc. In some cases, significant weight reduction may not be observed as compared with the case where the hollow body is not employed. The results of Comparative Example 1 and Comparative Example 2 show that the mass of the glass-based hollow body relative to the resin-based hollow body is not adopted as the component of the second liquid, because the glass-based hollow body with 90 vol. It is expected that the ratio is not in the range of 0.4 or more and 1.2 or less.

  In Comparative Example 3, since the average particle diameter of the resin-based hollow body exceeds 50 μm, springback is appropriately prevented from occurring in the sealing material composition obtained by mixing the first liquid and the second liquid. Can not.

In Comparative Example 4, although the second liquid is reduced in weight as in Example 3, since it does not contain a resin-based hollow body, sufficient physical properties and durability which are the original functions of the sealing material after curing are sufficient. Could not be secured.

Claims (3)

It consists of a first liquid containing a urethane prepolymer and a second liquid containing a polyol,
The second liquid contains a glass-based hollow body having a 90% by volume residual pressure resistance of 2.5 MPa or more, and a resin-based hollow body having an average particle diameter of 10 μm to 50 μm,
The two-component curable polyurethane sealing material composition in which the mass ratio of the glass-based hollow body to the resin-based hollow body (mass of the glass-based hollow body / mass of the resin-based hollow body) is 0.4 to 1.2. object.   The two-component curable polyurethane-based sealing material according to claim 1, wherein a total content of the glass-based hollow body and the resin-based hollow body is 10% by mass or more and 20% by mass or less with respect to the mass of the second liquid. Composition.   The two-component curable polyurethane-based sealing material composition according to claim 1 or 2, wherein the 90% by volume residual compressive strength of the glass-based hollow body is 5 MPa or more.