JP4926452B2 - Resin composition for precast concrete plate and precast concrete plate using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition for a precast concrete panel excellent in heat resistance, water resistance and alkali resistance, capable of keeping physical properties and adhesiveness over a long period of time even under a strong alkaline environment like a concrete surface and capable of preventing efflorescence. <P>SOLUTION: The resin composition for a precast concrete panel comprises a urethane prepolymer (A) obtained by reacting tetramethylxylidenediisocyanate and a polyol compound, and an imine compound (B) having an imino (&gt;C=N-) bond derived from a ketone or an aldehyde and an amine. The precast concrete panel comprises at least two decorative plates 3 installed so as to leave the interval corresponding to a joint part 2, the back treatment materials 5 applied to the backs of the decorative plates 3, the panel like base materials 7 integrally attached to the backs of the decorative plates 3 through the back treatment materials 5 and composed of concrete 7a and reinforcements 7b, and the joint material 9 charged in the joint part 2. The back treatment materials 5 and the joint material 9 are constituted of the resin composition. <P>COPYRIGHT: (C)2007,JPO&amp;INPIT

Description

  The present invention relates to a resin composition for a precast concrete plate and a precast concrete plate using the same.

In recent years, at the construction site of a high-rise building, a so-called curtain wall method is generally used in which a precast concrete plate (PC plate) produced in advance at a factory is suspended with a crane and fixed with bolts. This PC version is used not only on the outer wall of the building but also on the inner wall surface, floor surface, and the like.
Conventionally, in the manufacture of PC plates, the back of the decorative board is treated with a silicone-based material or modified silicone / epoxy-based material, or these materials are filled in joints to adhere the decorative board to the concrete substrate. In addition, the invasion of moisture from the voids and joints of the decorative plate was prevented, and efflorescence (white flower phenomenon) was prevented (see, for example, Patent Documents 1 and 2).

Japanese Patent Publication No. 61-13986 JP-A-2-308877

However, when the silicone material described in Patent Document 1 is used, there is a problem that the silicone oil oozes out over time and contaminates the decorative plate surface.
On the other hand, when the modified silicone / epoxy-based material described in Patent Document 2 is used, the flexibility decreases due to the influence of heat and water, and the performance of absorbing dissimilar materials, following the cracks, preventing crack scattering, etc. decreases. There was a problem to do. In general, concrete is strongly alkaline because it contains calcium hydroxide and the like, but the modified silicone / epoxy-based material has insufficient alkali resistance, and particularly has a problem in alkali hot water adhesion resistance. When the joint material is peeled off, efflorescence may occur.

Therefore, the present invention is a resin composition for precast concrete plates that is excellent in heat resistance, water resistance and alkali resistance, can maintain physical properties and adhesion over a long period of time even in a strong alkaline environment such as a concrete surface, and can prevent efflorescence. The purpose is to provide.
Another object of the present invention is to provide a precast concrete plate that is excellent in heat resistance, water resistance, and alkali resistance, can maintain physical properties and adhesion over a long period of time, and can prevent efflorescence.

  As a result of intensive studies, the present inventor has found that a urethane prepolymer (A) obtained by reacting tetramethylxylylene diisocyanate and a polyol compound, a ketone or aldehyde, and an imino (> C = N) derived from an amine. -) When the imine compound (B) having a bond is contained, it has excellent heat resistance, water resistance and alkali resistance, and can maintain physical properties and adhesiveness over a long period of time in a strong alkaline environment such as a concrete surface. It was found that the resin composition for precast concrete plates can be prevented, and the present invention was completed.

That is, the present invention provides the following (1) to (8).
(1) An imine compound having an imino (> C = N-) bond derived from a urethane prepolymer (A) obtained by reacting tetramethylxylylene diisocyanate with a polyol compound, a ketone or an aldehyde, and an amine A resin composition for a precast concrete plate containing (B).
(2) The resin composition for a precast concrete plate according to (1), further comprising calcium carbonate (C) surface-treated with a urethane compound.
(3) The resin composition for a precast concrete plate according to (1) or (2), further comprising an epoxy resin (D).
(4) The above (2) containing 1 to 500 parts by mass of calcium carbonate (C) surface-treated with the urethane compound with respect to a total of 100 parts by mass of the urethane prepolymer (A) and the epoxy resin (D). ) Or the resin composition for precast concrete plates according to (3).
(5) Active hydrogen that can be generated from the imine compound (B) with respect to the total number of isocyanate groups of the urethane prepolymer (A) and epoxy groups of the epoxy resin (D). The resin composition for precast concrete plates according to any one of the above (1) to (4), which is contained in an amount such that the ratio of the number of the above becomes 0.01-4.
(6) The precast concrete plate according to any one of (3) to (5), wherein the epoxy resin (D) is contained in an amount of 0.5 to 100 parts by mass with respect to 100 parts by mass of the urethane prepolymer (A). Resin composition.
(7) Two or more decorative plates installed at intervals corresponding to joint portions, a back surface treatment material applied to the back surface of the decorative plate, and the back surface material on the back surface of the decorative plate A precast concrete plate having a plate-like base material made of concrete integrally attached and a joint material filled in the joint part,
The precast concrete plate whose said back surface treatment material is the resin composition for precast concrete plates in any one of said (1)-(6).
(8) The precast concrete plate according to (7), wherein the joint material is the resin composition for a precast concrete plate according to any one of (1) to (6).

The resin composition for a precast concrete plate of the present invention is excellent in heat resistance, water resistance and alkali resistance, and can maintain physical properties and adhesiveness for a long period even in a strong alkaline environment such as a concrete surface, and can prevent efflorescence.
Further, the precast concrete plate of the present invention is excellent in heat resistance, water resistance and alkali resistance, and can maintain physical properties and adhesiveness over a long period even in a strong alkaline environment such as a concrete surface, and can prevent efflorescence.

Hereinafter, the present invention will be described in more detail.
The resin composition for precast concrete plates of the present invention (hereinafter also referred to as “the composition of the present invention”) is a urethane prepolymer (A) obtained by reacting tetramethylxylylene diisocyanate with a polyol compound, It contains a ketone or aldehyde and an imine compound (B) having an imino (> C═N—) bond derived from an amine.

<Urethane prepolymer (A)>
The urethane prepolymer (A) used in the composition of the present invention is obtained by reacting tetramethylxylylene diisocyanate (TMXDI) with a polyol compound.
The polyol compound is an alcohol obtained by replacing a plurality of hydrocarbon hydrogens with a hydroxy group. Examples thereof include a product obtained by addition polymerization of at least one alkylene oxide such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran to an active hydrogen-containing compound having two or more active hydrogens in the molecule.

Examples of the active hydrogen-containing compound include polyhydric alcohols, amines, alkanolamines, polyhydric phenols, and the like.
Specific examples of the polyhydric alcohols include ethylene glycol, propylene glycol, butanediol, diethylene glycol, glycerin, hexanetriol, trimethylolpropane, pentaerythritol and the like.
Specific examples of amines include ethylenediamine and hexamethylenediamine.
Specific examples of alkanolamines include ethanolamine and propanolamine.
Specific examples of polyhydric phenols include resorcin and bisphenols.

Specific examples of the polyol compound include polyether-based polyols such as polytetramethylene glycol, polyethylene glycol, polypropylene glycol, polyoxypropylene glycol, and polyoxybutylene glycol; polyolefins such as polybutadiene polyol and polyisoprene polyol. Examples include polyols; adipate-based polyols; lactone-based polyols; polyester-based polyols such as castor oil.
These may be used alone or in combination of two or more.

  The polyol compound preferably has a weight average molecular weight of about 500 to 10000, more preferably about 2000 to 6000.

  The ratio of the number of isocyanate groups of TMXDI to the number of hydroxy groups of the polyol compound (NCO / OH) is 1.2 or more when the ratio of TMXDI and the polyol compound in the production of the urethane prepolymer (A) is 1.2. It is preferable that it is 1.5 to 2.0.

  The production of the urethane prepolymer (A) is usually performed by mixing a predetermined amount ratio of an isocyanate group-containing compound and a polyol compound and heating and stirring at 60 to 100 ° C. under normal pressure, as in the case of a normal urethane prepolymer. Can be done.

<Imine Compound (B)>
The imine compound (B) used in the composition of the present invention is a compound having an imino (> C═N—) bond derived from a ketone or an aldehyde and an amine, and specifically, from a ketone and an amine. Examples include ketimines derived from aldimines derived from aldehydes and amines.

  As the ketone or aldehyde used for the synthesis of such an imine compound (B), widely known ones can be used, and examples thereof include compounds represented by the following formula (1) or (2). Among them, a compound represented by the following formula (1) in which at least one α-position carbon of the ketone carbonyl group or the α-position carbon of the aldehyde carbonyl group is a secondary carbon or a tertiary carbon. Is preferred.

In the above formula (1), R ¹¹ and R ¹³ each independently represent a methyl group, an ethyl group or a hydrogen atom, R ¹² represents a methyl group or an ethyl group, and R ¹⁴ has 1 to 6 carbon atoms. Represents an alkyl group. However, R ¹⁴ can combine with R ¹¹ or R ¹² to form a ring. R ¹⁴ is bonded to R ¹² to form a ring, and among the carbon atoms at the α-position of the carbonyl group, the carbon atom contained in the ring is bonded to R ¹² or R ¹⁴ with a double bond. In this case, R ¹³ is not present. When R ¹⁴ is bonded to R ¹¹ or R ¹² to form a ring, examples of the formed cyclic hydrocarbon include alicyclic hydrocarbons and aromatic hydrocarbons.
In the above formula (2), R ¹⁵ and R ¹⁶ each independently represents an alkyl group having 1 to 6 carbon atoms, and R ¹⁵ and R ¹⁶ can be bonded to each other to form a ring. When R ¹⁵ and R ¹⁶ are combined to form a ring, examples of the formed cyclic hydrocarbon include alicyclic hydrocarbons and aromatic hydrocarbons.

  The compound represented by the above formula (1) is, as described above, one of the carbon atoms at the α-position of the carbon atom (hereinafter also referred to as “imine carbon atom”) that forms an imino bond when iminized. Has 2 or 3 substituents, which are so-called branched carbon atoms. In the compound represented by the above formula (1), since the imine carbon atom has a bulky group and a relatively bulky group as described above, both curability and pot life are in a suitable range.

  In the compound represented by the above formula (2), both of the α-position carbon atoms of the imine carbon atom are not branched carbon atoms, but both are bonded to an alkyl group having 1 to 6 carbon atoms. ing. Further, the two alkyl groups having 1 to 6 carbon atoms can be bonded to each other to form a ring. Since the compound represented by the formula (2) has an imine carbon atom having 2 alkyl groups having 2 to 7 carbon atoms, both curability and pot life are within a preferable range.

Specific examples of the compound represented by the above formula (1) include methyl isobutyl ketone (MIBK), methyl t-butyl ketone (MTBK), methyl isopropyl ketone (MIPK), and pivalaldehyde (trimethylacetaldehyde). And isobutyraldehyde ((CH ₃ ) ₂ CHCHO) in which a branched carbon is bonded to a carbonyl group, methylcyclohexanone, ethylcyclohexanone, methylcyclohexyl ketone, acetophenone, propiophenone, and the like. May be used in combination. Of these, MTBK and MIPK are preferred.

  Specific examples of the compound represented by the formula (2) include diethyl ketone, dipropyl ketone, dibutyl ketone, ethyl propyl ketone, ethyl butyl ketone, butyl propyl ketone, ethyl isopropyl ketone, and ethyl amyl. A ketone, cyclohexanone, etc. are mentioned, These may be used independently or may use 2 or more types together. Of these, diethyl ketone, dipropyl ketone, and dibutyl ketone are preferred.

  On the other hand, as an amine compound that can be used as a raw material for the synthesis of the imine compound (B), widely known compounds can be used, and a polyamine having two or more amino groups in the molecule is preferable. More preferred are aliphatic polyamines and / or alicyclic polyamines. Moreover, it is more preferable that it is a polyamine represented by following formula (3) from a viewpoint that reaction adjustment is easy.

（式中、ｎは、２〜６の整数を表す。）

(In the formula, n represents an integer of 2 to 6.)

  Specific examples of the amine compound include ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, triethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, trimethylhexamethylenediamine, 1, Aliphatic polyamines such as 2-propanediamine, iminobispropylamine, methyliminobispropylamine, 1,5-diamino-2-methylpentane (MPMD, manufactured by DuPont Japan); metaphenylenediamine, orthophenylenediamine, Such as paraphenylenediamine, m-xylylenediamine (MXDA), diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiethyldiphenylmethane Aromatic polyamine; N-aminoethylpiperazine; monoamine having an ether bond in the main chain such as 3-butoxyisopropylamine; diamine of polyether skeleton represented by Jeffamine EDR148 manufactured by Sun Techno Chemical Co .; isophorone diamine, 1, Alicyclic polyamines such as 3-bisaminomethylcyclohexane (1,3BAC, manufactured by Mitsubishi Gas Chemical Company), 1-cyclohexylamino-3-aminopropane, 3-aminomethyl-3,3,5-trimethyl-cyclohexylamine A diamine having a norbornane skeleton such as norbornanediamine (NBDA, manufactured by Mitsui Chemicals); a polyamideamine having an amino group at the molecular end of the polyamide; 2,5-dimethyl-2,5-hexamethylenediamine, mensendiamine, 1 , 4-bis (2-a No-2-methylpropyl) piperazine, Jeffermine D230 and Jeffamine D400 manufactured by Sun Techno Chemical Co., which have polypropylene glycol (PPG) as a skeleton, and these may be used alone or in combination of two or more. Also good.

  Of these, 1,3-bisaminomethylcyclohexane (1,3BAC), norbornanediamine (NBDA), m-xylylenediamine (MXDA), Jeffamine EDR148 (trade name), and polyamidoamine are preferable.

As described above, the imine compound (B) is a compound derived from a ketone or aldehyde and an amine, and examples thereof include combinations of various ketones or aldehydes exemplified above and various amines.
Specifically, obtained from MIBK and propylenediamine; obtained from MIPK and / or MTBK and Jeffamine EDR148; obtained from MIPK and / or MTBK and 1,3BAC; MIPK and / or MTBK Preferably obtained from MIPK and / or MTBK and MXDA; obtained from MIPK and / or MTBK and polyamidoamine; obtained from diethyl ketone and MXDA; Is done.
Of these, those obtained from MIPK or MTBK and 1,3BAC; those obtained from MIPK or MTBK and NBDA; those obtained from MIPK or MTBK and MXDA are the storage stability and curing of the resulting composition It is preferable because of its excellent properties.

  Further, as the imine compound (B) obtained from the combination of aldehyde and polyamine, specifically, at least one aldehyde selected from the group consisting of pivalaldehyde, isobutyraldehyde and cyclohexanecarboxaldehyde, and NBDA Preferred examples include those obtained from a combination with at least one amine selected from the group consisting of 1,3BAC, Jeffamine EDR148 and MXDA.

  Such an imine compound (B) is obtained by heating and refluxing ketone or aldehyde and amine in the absence of a solvent or in the presence of a solvent such as benzene, toluene, xylene, etc. It can be obtained by reacting.

  The content of the imine compound (B) is based on the total number of isocyanate groups possessed by the urethane prepolymer (A) and epoxy groups possessed by the epoxy resin (D) described later (when the epoxy resin (D) is not contained, the urethane prepolymer The ratio of the number of active hydrogens that can be generated from the imine compound (B) to the number of isocyanate groups of the polymer (A) is preferably 0.01 to 4, and preferably 0.5 to 2.0. It is more preferable that the amount is such that the amount becomes 0.8 to 1.2. If content of imine compound (B) is this range, the adhesiveness of the composition of this invention obtained will improve more.

<Calcium carbonate surface-treated with urethane compound (C)>
The composition of the present invention preferably further contains calcium carbonate (C) surface-treated with a urethane compound (hereinafter referred to as “calcium carbonate (C)”). The said calcium carbonate (C) is not specifically limited, The calcium carbonate surface-treated with the well-known urethane compound can be used.

The urethane compound used for the surface treatment of calcium carbonate (C) is not particularly limited as long as it is a compound having at least one urethane bond (—NHCOO—) in the molecule, and is obtained by a reaction between an isocyanate compound and a polyol compound. And those obtained by the reaction of an isocyanate compound and a carboxylic acid, and allophanates obtained by the reaction of a urethane compound and an isocyanate compound.
As said isocyanate compound, an aromatic type, an aliphatic type, an alicyclic type, or what mixed these 2 or more types can be used.
As said polyol compound, the polyol used for manufacture of the urethane prepolymer mentioned above can be used, for example.

  Moreover, it is preferable that the said urethane compound is a compound (henceforth a urethane compound of Formula (4)) represented by following formula (4).

  In the formula, X represents a residue obtained by removing an isocyanate group from an isocyanate compound, or a residue obtained by removing an amino group from an amine compound. m represents an integer of 1 to 4, R ′ represents a hydrocarbon group, and when m is 2, 3 or 4, a plurality of R ′ may be the same or different. Further, at least one of R ′ represents a hydrocarbon group having 8 or more carbon atoms.

Specific examples of the method for synthesizing the urethane compound of the above formula (4) include a method of reacting an isocyanate compound (X- (NCO) _m ) with an alcohol (R′OH), an isocyanate compound and a carboxylic acid. Or a method of reacting carbonyl chloride (X- (OCOCl) _m ) with an amine can be used.

  As the isocyanate compound used for the synthesis of the urethane compound of the above formula (4), a compound having 1 to 4 isocyanate groups in the molecule, and all known isocyanate compounds used for the synthesis of urethane resins and the like can be used. is there.

As said isocyanate compound, a monoisocyanate compound, a diisocyanate compound, a triisocyanate compound, a tetraisocyanate compound etc. are illustrated below.
Specific examples of the monoisocyanate compound include phenyl isocyanate and stearyl isocyanate.
Specific examples of the diisocyanate compound include aromatic isocyanates such as paraphenylene diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, and 4,4′-diphenylmethane diisocyanate; aliphatics such as tetramethylene diisocyanate, hexamethylene diisocyanate, and octadecyl diisocyanate. Isocyanates; Cycloaliphatic isocyanates such as isophorone diisocyanate; Aryl aliphatic isocyanates such as xylylene diisocyanate; Modified isocyanates of each of the above isocyanates.

Specific examples of the triisocyanate compound include a reaction product of the above diisocyanate compound and a polyhydric alcohol such as glycerin, hexanetriol, and trimethylolpropane, or a diisocyanate such as tetramethylene diisocyanate and hexamethylene diisocyanate. Examples thereof include compounds having three isocyanate groups in one molecule obtained by forming an isocyanurate ring.
Specific examples of the tetraisocyanate compound include, for example, four isocyanate groups per molecule obtained by the reaction of the diisocyanate compound and the like with a diurethane obtained by reacting with a dialcohol, and two molecules of diisocyanate. And the like.
These isocyanate compounds may be used alone or in combination of two or more.

Specific examples of the alcohol (R′OH) used for the synthesis of the urethane compound of the above formula (4) include, for example, methanol, ethanol, propanol, isopropanol, butanol, pentanol, hexanol, heptanol, benzyl alcohol, and allyl. In addition to lower alcohols such as alcohol, higher grades such as n-octyl alcohol, 2-ethylhexanol, nonyl alcohol, n-decyl alcohol, undecyl alcohol, n-tridecyl alcohol, misty alcohol, n-hexadecyl alcohol, stearyl alcohol Examples include alcohol.
As the combination of the isocyanate compound and the alcohol, a combination of tolylene diisocyanate and stearyl alcohol is particularly preferable.

Specific examples of the carboxylic acid used for the synthesis of the urethane compound represented by the formula (4) include fatty acids such as lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and behenic acid, and resin acids. Can be mentioned.
As a combination of the above-mentioned isocyanate compound and carboxylic acid, a combination of tolylene diisocyanate and stearic acid is particularly preferable.

Specific examples of the carbonyl chloride (X- (OCOCl) _m ) used for the synthesis of the urethane compound of the above formula (4) include, for example, methyl chlorocarbonate, ethyl chlorocarbonate, propyl chlorocarbonate, butyl chlorocarbonate. Benzyl chlorocarbonate, octyl chlorocarbonate, nonyl chlorocarbonate, decyl chlorocarbonate, undecyl chlorocarbonate, okdadecyl chlorocarbonate, benzyl chlorocarbonate and the like.

Specific examples of the amine used for the synthesis of the urethane compound represented by the formula (4) include octylamine, laurylamine, stearylamine, oleylamine, m-phenylenediamine, and p-phenylenediamine.
As the above-mentioned combination of carbonyl chloride and amine, a combination of m-phenylenediamine and okdadecyl chlorocarbonate is particularly preferable.

  R ′ in the above formula (4) is a hydrocarbon group, but at least one of R ′ needs to be a hydrocarbon group having 8 or more carbon atoms. The presence of a hydrocarbon group having 8 or more carbon atoms in one molecule is preferable because the storage stability of the composition containing the urethane compound of the above formula (4) is improved.

  In addition, the urethane compound used in the present invention including the urethane compound of the above formula (4) has a melting point of 50 ° C. or more, and the urethane compound does not melt during the production of the one-component moisture-curable resin composition. Preferred for reasons.

  Although the usage-amount of the urethane compound used for this invention including the urethane compound of the said Formula (4) does not have a restriction | limiting in particular, a urethane compound is 1-20 mass% with respect to calcium carbonate, Preferably it is 2-10 mass%. It is. If the usage-amount of a urethane compound is this range, the effect of surface treatment is fully acquired and it is preferable from the reason that the physical property of the composition after hardening does not fall.

  The surface treatment of calcium carbonate (C) may be performed by using carboxylic acid, sulfonic acid, or a metal salt thereof in combination with the urethane compound. The composition of the present invention containing calcium carbonate (C) by using carboxylic acid, sulfonic acid, or a metal salt thereof, and the urethane compound used in the present invention together with the surface treatment of calcium carbonate (C). This is preferable because the storage stability of the product is improved.

As the carboxylic acid, sulfonic acid, or a metal salt thereof (hereinafter also referred to as a fatty acid), all of those generally used as a treatment agent for calcium carbonate can be used. Specifically, for example, lauric acid, Examples thereof include fatty acids such as myristic acid, palmitic acid, stearic acid, oleic acid, and behenic acid, sulfonic acids such as resin acid, dodecylbenzenesulfonic acid, and metal salts thereof.
Specific examples of the metal in the metal salt include potassium, sodium, aluminum, calcium, magnesium and the like. Among these, it is particularly preferable to use a metal salt of a fatty acid.

The surface treatment method of calcium carbonate using carboxylic acid, sulfonic acid, or a metal salt thereof is not particularly limited. For example, calcium carbonate and carboxylic acid, sulfonic acid, or Examples thereof include a method of vigorously stirring these metal salts with a mixer or the like.
Although the usage-amount of carboxylic acid, a sulfonic acid, or these metal salts does not have a restriction | limiting in particular, It is 0.5-10 mass% with respect to calcium carbonate, Preferably it is 1-8 mass%. It is preferable that the amount of carboxylic acid, sulfonic acid, or a metal salt thereof is within this range because a sufficient surface treatment effect can be obtained and sufficient storage stability can be obtained as a one-component moisture-curable resin.

As the untreated calcium carbonate for obtaining calcium carbonate (C), those having a specific surface area of 3 m ² / g or more by the BET method are used. It is preferable to use precipitated calcium carbonate as untreated calcium carbonate because the thixotropy of calcium carbonate (C) is excellent.

Further, the method of adding the urethane compound to be surface-treated with calcium carbonate and the fatty acid to be added as desired is not particularly limited, and specifically, for example, calcium carbonate or already treated with fatty acid or the like. A method in which calcium carbonate and the urethane compound used in the present invention are mixed and heated to a temperature equal to or higher than the melting point of the urethane compound (dry treatment);
A method in which a urethane compound used in the present invention is mixed with calcium carbonate or an aqueous slurry of calcium carbonate that has already been treated with a fatty acid and the like, heated above the melting point of the urethane compound, dehydrated, dried, and pulverized (wet treatment). ;
When producing ordinary precipitated calcium carbonate, preferably a urethane compound used in the present invention having a particle size of 100 μm or less is added and dried at a temperature equal to or higher than the melting point of the urethane compound. Can be added at any place).

  The content of calcium carbonate (C) is 100 parts by mass with respect to a total of 100 parts by mass of the urethane prepolymer (A) and the epoxy resin (D) described below (when no epoxy resin (D) is contained, the urethane prepolymer (A) 100). 1 to 500 parts by mass, preferably 10 to 300 parts by mass, and more preferably 50 to 200 parts by mass. Within this range, the cured material properties are excellent.

  Since the composition of this invention contains calcium carbonate (C), it is excellent in storage stability and hardened | cured material property.

<Epoxy resin (D)>
The composition of the present invention preferably further contains an epoxy resin (D). By containing an epoxy resin (D), adhesiveness improves more.
The epoxy resin (D) used in the composition of the present invention is a compound having at least one epoxy group. Specifically, for example, bisphenol A, bisphenol F, bisphenol S, hexahydrobisphenol A, tetramethylbisphenol A, pyrocatechol, resorcinol, cresol novolac, tetrabromobisphenol A, trihydroxybiphenyl, bisresorcinol, bisphenol hexafluoroacetone Glycidyl ether type obtained by reaction of polychlorophenol such as tetramethylbisphenol F, bixylenol, dihydroxynaphthalene and epichlorohydrin; glycerin, neopentyl glycol, ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, polyethylene glycol, Aliphatic polyhydric alcohols such as polypropylene glycol and epichlorohydrin Polyglycidyl ether type obtained by the reaction of glycidyl ether ester type obtained by the reaction of hydroxycarboxylic acid such as p-oxybenzoic acid and β-oxynaphthoic acid and epichlorohydrin; phthalic acid, methylphthalic acid, isophthalic acid, terephthalic acid , Tetrahydrophthalic acid, hexahydrophthalic acid, endomethylenetetrahydrophthalic acid, endomethylenehexahydrophthalic acid, trimellitic acid, polyglycidyl ester type derived from polycarboxylic acid such as polymerized fatty acid; aminophenol, aminoalkylphenol Glycidylaminoglycidyl ether type derived from glycidylaminoglycidyl ester type derived from aminobenzoic acid; aniline, toluidine, tribromoaniline, xylylenediamine Glycidylamine type derived from amine, diaminocyclohexane, bisaminomethylcyclohexane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, etc .; epoxidized polyolefin, glycidylhydantoin, glycidylalkylhydantoin, triglycidylsia Examples include nurate. These may be used alone or in combination of two or more.

  Moreover, it is preferable that the said epoxy resin (D) has at least 1 aromatic ring from the point which is excellent in the physical property of cured | curing material, heat resistance, and water resistance. In particular, bisphenol A-type and bisphenol F-type epoxy compounds are preferable because they are easily available and have a good balance of properties (performance) of the cured product.

  The content of the epoxy resin (D) is preferably 0.5 to 100 parts by mass, more preferably 1 to 50 parts by mass with respect to 100 parts by mass of the urethane prepolymer (A). More preferably, it is part by mass. When the content of the epoxy resin (D) is within this range, the heat resistance, water resistance and alkali resistance can be maintained at a high level.

<Additives>
The composition of the present invention is, as necessary, a filler, a reaction retardant, an anti-aging agent, an antioxidant, a pigment (dye), a plasticizer, and a thixotropic agent, as long as the object of the present invention is not impaired. , Ultraviolet absorbers, flame retardants, solvents, surfactants (including leveling agents), dispersants, dehydrating agents, adhesion-imparting agents, antistatic agents, and other various additives.

  Specific examples of the plasticizer include, for example, dioctyl phthalate (DOP), dibutyl phthalate (DBP); dioctyl adipate, isodecyl succinate; diethylene glycol dibenzoate, pentaerythritol ester; butyl oleate, methyl acetylricinoleate; phosphorus Examples include tricresyl acid, trioctyl phosphate; propylene glycol polyester adipate, butylene glycol polyester adipate, and the like.

  Specific examples of the adhesion-imparting agent include terpene resins, phenol resins, terpene-phenol resins, rosin resins, xylene resins; silane coupling agents such as epoxy silane and isocyanate silane.

  Specific examples of the dehydrating agent include, for example, methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, trimethyl orthopropionate, triethyl orthopropionate, trimethyl orthoisopropionate, triethyl orthoisopropionate, Hydrolyzable ester compounds such as trimethyl orthobutyrate, triethyl orthobutyrate, trimethyl orthoisobutyrate, triethyl orthoisobutyrate; or dimethoxymethane, 1,1-dimethoxyethane, 1,1-dimethoxypropane, 1,1-dimethoxybutane; or Ethyl silicate (tetramethoxysilane), methyl silicate (tetramethoxysilane), methyltrimethoxysilane; vinyltrimethoxysilane, vinyltriethoxysilane, and other vinylsilanes. These may be used alone or in combination of two or more. Among these, vinylsilane is preferable from the viewpoint of dehydration effect.

  The production method of the composition of the present invention is not particularly limited. For example, a method in which each of the above essential components and optional components are put in a reaction vessel and sufficiently kneaded using a stirrer such as a mixing mixer under reduced pressure. Can be used.

The composition of the present invention can be a one-component moisture curable type, and as described above, the imine compound (B) is hydrolyzed by moisture to produce an amino group, and thus has excellent curability.
Further, the composition of the present invention is excellent in heat resistance, water resistance and alkali resistance, and can maintain physical properties and adhesiveness over a long period even in a strong alkaline environment such as a concrete surface. As a result, the intrusion of moisture can be suppressed over a long period of time, so that efflorescence can be prevented.

Hereinafter, the precast concrete plate of the present invention will be described in detail.
The precast concrete plate of the present invention (hereinafter referred to as “the PC plate of the present invention”) was applied to two or more decorative plates installed at intervals corresponding to joint portions and the back surface of the decorative plate. A precast concrete plate comprising a back surface treatment material, a plate-like base material made of concrete integrally attached to the back surface of the decorative board via the back surface treatment material, and a joint material filled in the joint portion. The back treatment material is a precast concrete plate that is the above-described resin composition for a precast concrete plate of the present invention.
In the PC plate of the present invention, the “back surface” refers to the plate-like substrate side (the lower side in FIG. 2) in the PC plate of the present invention, and the “front surface” refers to the decorative plate side (see FIG. 2 upper side).

  In the PC plate of the present invention, the joint material is preferably the resin composition for a precast concrete plate of the present invention. In the PC plate of the present invention, at least the above-mentioned backside treatment material may be the composition of the present invention. Furthermore, when the jointing material is also the composition of the present invention, the jointing material and the backside treatment material are formed of the same material. Therefore, it is preferable because a gap is hardly generated at the boundary between the joint material and the back surface treatment material even when the material is distorted. Moreover, when the said back surface treatment material and the said joint material are comprised from the composition of this invention, it is excellent in heat resistance, water resistance, and alkali resistance, and can maintain a physical property and adhesiveness over a long period of time. As a result, the intrusion of moisture can be suppressed over a long period of time, so that efflorescence can be prevented.

Hereinafter, an example of a preferred embodiment of the PC plate of the present invention will be specifically described with reference to the drawings.
FIG. 1 is a perspective view of an example of a preferred embodiment of the PC plate of the present invention. FIG. 2 is an enlarged cross-sectional view taken along the line AA ′ in FIG.
The PC plate 1 of the present invention includes two or more decorative plates 3 installed at intervals corresponding to the joints 2, a back surface treatment material 5 applied to the back surface of the decorative plate 3, and the back surface of the decorative plate 3. A precast concrete plate having a plate-like base material 7 made of concrete 7a and a reinforcing bar 7b integrally attached to a back surface treatment material 5 and a joint material 9 filled in the joint portion 2, The processing material 5 and the joint material 9 are comprised from the composition of this invention mentioned above.

In addition, although the plate-shaped base material 7 does not have the reinforcing bar 7b and may be comprised only from the concrete 7a, it is preferable to be comprised from the concrete 7a which embedded the reinforcing bar 7b from the point which is excellent in intensity | strength.
Moreover, the joint material 9 may be comprised from compositions other than the composition of this invention. Conventional joint materials other than the composition of the present invention include, for example, elastic epoxy resin, urethane resin, chlorosulfonated polyethylene rubber (CSM), silicone rubber (SR), chloroprene rubber (CR), ethylene propylene rubber (EPDM). And modified silicone resins.
Furthermore, the sealing material can be filled in the concave portion on the surface side of the joint material 9. Examples of the sealing material include urethane resin, modified silicone resin, polysulfide rubber, polyisobutylene rubber and the like.

  The number of decorative plates 3 used in the PC plate of the present invention is not particularly limited as long as it is two or more. The material of the decorative board 3 will not be specifically limited if it is normally used for PC version, A stone material, a ceramic board, etc. are mentioned.

  Moreover, the space | interval of the joint part 2 in the PC plate of this invention, the magnitude | size of the concrete 7a, the reinforcing bar 7b, and the PC plate, etc. may be the same as a normal PC plate, and are not specifically limited.

Next, an example of a method for producing a PC plate according to the present invention will be specifically described with reference to FIG.
FIGS. 3A to 3E are partially enlarged sectional views in the manufacturing process of the PC plate of the present invention. First, a predetermined number of decorative plates 3 are placed on the mold K at an interval corresponding to the joint portion 2 so that the surface (the lower surface in the drawing) is in contact with the mold K (see FIG. 3A).
In the joint portion 2, a polyethylene foam backup material 11 is inserted so as to be in contact with the formwork K, and the back surface treatment material 5 is applied to the back surface (upper surface in the drawing) of each decorative board 3 (see FIG. 3B). ). In addition, you may apply | coat the back surface treatment material 5 to the back surface of the decorative board 3 previously.
Next, the joint material 9 is filled in the joint portion 2 so as to reach a substantially middle portion of the joint depth (see FIG. 3C).
Next, concrete 7a is driven so as to cover the back surface treatment material 5 and the joint material 9, and when the thickness of the concrete 7a reaches about half of the predetermined dimension of the plate-like base material 7, the rebar 7b is spaced at an appropriate interval. Furthermore, the concrete 7a is driven in until the wall thickness reaches a predetermined dimension of the plate-like base material, and the concrete 7a that is driven in this state is cured until it hardens (see FIG. 3 (d)).
After curing, it is removed from the formwork K, and the backup material inserted into each joint portion 2 is taken out to obtain the precast concrete plate of the present invention (see FIG. 3 (e)).
Further, a sealing material may be filled in a recess formed by taking out the backup material (not shown).

  As described above, the PC plate of the present invention is excellent in heat resistance, water resistance and alkali resistance and can maintain physical properties and adhesion over a long period of time because at least the back treatment material is composed of the composition of the present invention. , Can prevent efflorescence. Furthermore, when the joint material is composed of the composition of the present invention, since the joint material and the back surface treatment material are formed of the same material, the joint material and the back surface treatment material can be used even when the material is distorted. It becomes difficult to produce a gap at the boundary.

Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to these.
(Examples 1-6 and Comparative Examples 1-2)
Each component of the following Table 1 was mixed with the composition (parts by mass) shown in Table 1 using a stirrer to obtain each composition shown in Table 1. In Table 1, the amount of the imine compound indicates an equivalent ratio of active hydrogen that can be generated from the imine compound to the total of the isocyanate group of the TMXDI prepolymer and the epoxy group of the epoxy resin.
Using the obtained compositions, the viscosity, tack free time (surface curability), dumbbell physical properties, and adhesiveness were evaluated by the following methods.
The results are shown in Table 2.

<Viscosity>
About the composition of Examples 1-3, each composition immediately after obtained was rotated by 23 degreeC and 1 rpm using the No. 7 rotor with BS type | mold viscosity meter, and the viscosity was measured.
Moreover, about the composition of Examples 4-6 and Comparative Examples 1-2, each composition immediately after obtained was rotated at 23 degreeC and 2 rpm using a No. 6 rotor with a BH type | mold viscosity meter, and a viscosity was measured. It was measured.

<Tack-free time>
Each composition immediately after being obtained was cured under conditions of 23 ° C. and 50% RH, and tack-free time was measured according to JIS A1439-2004.

<Dumbell physical properties>
(initial)
According to JIS K6251-2004, each composition was cured at 23 ° C. and 50% RH for 336 hours, and then cut into a dumbbell shape (dumbbell shape No. 5) to obtain a test piece. Using this test piece, the breaking strength (T _B ) and the breaking elongation (E _B ) were measured.
(Heat-resistant)
Using a test piece prepared in the same manner as described above and further allowed to stand at 80 ° C. for 168 hours, the breaking strength (T _B ) and breaking elongation (E _B ) were measured.
(Alkaline hot water resistance)
A test piece produced in the same manner as the initial physical properties was further immersed in a saturated calcium hydroxide aqueous solution at 60 ° C. for 168 hours, and the breaking strength (T _B ) and breaking elongation (E _B ) were measured.

<Adhesiveness>
(initial)
In accordance with JIS A1439-2004, each composition obtained on a stone plate was applied and cured at 23 ° C. and 50% RH for 672 hours to prepare an H-type specimen. Granite was used as the stone plate.
Using the obtained specimen, it was pulled at a rate of 100 mm / min, and the tensile stress (T _B ) at break was measured. In addition, by visually observing the destruction state, the one that had been coherently destroyed over the entire cured product of the composition was designated as “CF”, and the one in which a part of the cured product of the composition was separated at the interface as “AF”. The ratio of the area obtained was expressed as a percentage (%).
(Heat-resistant)
Using a test specimen prepared in the same manner as described above and further allowed to stand at 80 ° C. for 168 hours, the tensile stress at break (T _B ) was measured by the same method as described above, and the fracture state was visually observed. .
(Alkaline hot water resistance)
Using a test piece prepared in the same manner as the initial physical properties and immersed in a saturated calcium hydroxide aqueous solution at 60 ° C. for 168 hours, the tensile stress at break (T _B ) was measured in the same manner as described above. The destruction state was visually observed.

<Eflorescence>
Moreover, it carried out similarly to the method shown in FIG. 3 mentioned above, and produced the PC plate using each composition obtained for the back surface treatment material and the joint material.
Each of the obtained PC plates was left outdoors for 4 months, and then the decorative board was visually observed to evaluate the presence or absence of efflorescence. Those with no efflorescence were marked with “○”.
The results are shown in Table 2.

Each component in Table 1 is as follows.
TMXDI prepolymer: Exenol 5030 (Asahi Glass Co., Ltd.) and Exenol 3030 (Asahi Glass Co., Ltd.) are mixed at a mass ratio of 3/1, and TMXDI (Nippon Cytec Co., Ltd.) is added in an amount such that NCO / OH = 2.0. Urethane prepolymer obtained by stirring and mixing (NCO% = 2.3%)
・ Modified silicone resin: MSP-S203, manufactured by Kaneka ・ Epoxy resin (bisphenol A type): YD128, manufactured by Tohto Kasei Co., Ltd. Light MBP, manufactured by Shiroishi Kogyo Co., Ltd. 918, manufactured by Sansha Kogyo Co., Ltd. ・ Imine compound: HOK-01, manufactured by Daito Sangyo Co., Ltd. ・ Plasticizer: DINP, manufactured by J Plus Co. ・ Dehydrating agent (vinyl silane): A171, manufactured by Nihon Unicar Co. Silane): A187, manufactured by Nihon Unicar

As is clear from the results shown in Table 2, the compositions of Comparative Examples 1 and 2 were inferior in elongation after breakage after heat aging and immersion in alkaline hot water, and adhesion after immersion in alkaline hot water.
On the other hand, the compositions of Examples 1 to 6 had extremely high elongation at break as compared with the compositions of Comparative Examples 1 and 2, and maintained physical properties and adhesiveness even after thermal aging and immersion in alkaline hot water. Further, the PC plates of Examples 1 to 6 were able to prevent efflorescence.

FIG. 1 is a perspective view of an example of a preferred embodiment of the PC plate of the present invention. FIG. 2 is an enlarged cross-sectional view taken along the line AA ′ in FIG. FIGS. 3A to 3E are partially enlarged sectional views in the manufacturing process of the PC plate of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 PC version of this invention 2 Joint part 3 Decorative plate 5 Back surface treatment material 7 Plate-like base material 7a Concrete 7b Reinforcement 9 Joint material 11 Backup material K Formwork

Claims (8)

  An imine compound (B) having an imino (> C = N-) bond derived from a urethane prepolymer (A) obtained by reacting tetramethylxylylene diisocyanate with a polyol compound, a ketone or an aldehyde, and an amine. And a resin composition for precast concrete plates.   Furthermore, the resin composition for precast concrete plates of Claim 1 containing the calcium carbonate (C) surface-treated with the urethane compound.   Furthermore, the resin composition for precast concrete plates of Claim 1 or 2 containing an epoxy resin (D).   The calcium carbonate (C) surface-treated with the urethane compound contains 1 to 500 parts by mass with respect to a total of 100 parts by mass of the urethane prepolymer (A) and the epoxy resin (D). The resin composition for precast concrete plates as described.   The number of active hydrogens that can be generated from the imine compound (B) with respect to the total number of the isocyanate groups of the urethane prepolymer (A) and the epoxy groups of the epoxy resin (D). The resin composition for precast concrete plates according to any one of claims 1 to 4, which is contained in an amount such that the ratio is 0.01 to 4.   The resin composition for precast concrete plates according to any one of claims 3 to 5, wherein the epoxy resin (D) is contained in an amount of 0.5 to 100 parts by mass with respect to 100 parts by mass of the urethane prepolymer (A). Two or more decorative plates installed at intervals corresponding to joint portions, a back surface treatment material applied to the back surface of the decorative plate, and the back surface of the decorative plate integrally with the back surface treatment material A precast concrete plate having a plate-like base material made of attached concrete and a joint material filled in the joint part,
A precast concrete plate, wherein the back treatment material is the resin composition for a precast concrete plate according to any one of claims 1 to 6.   The precast concrete plate according to claim 7, wherein the joint material is the resin composition for a precast concrete plate according to any one of claims 1 to 6.

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