JP7698414B2 - Chemical composition for consolidating natural ground - Google Patents

Description

The present invention relates to a liquid composition for consolidating ground, and in particular to a urethane-based liquid for consolidating ground that combines an active hydrogen group-containing organic compound having a cyclic structure with an aliphatic polyisocyanate compound to produce a high-strength consolidated body, has excellent reactivity, and is less likely to pollute the environment.

A method of injecting inorganic or organic grout to consolidate natural ground has been known for some time as a method for ground improvement to stabilize and strengthen unstable bedrock or ground, or for filling cracks or voids in man-made structures. For example, Japanese Patent Laid-Open Publication No. 4-283290 discloses, as one such grout, an injection liquid composition comprising an aqueous solution of sodium silicate (A) and a polyisocyanate composition (B) made of a reactive diluent that does not react with polyisocyanate but is hydrolyzed by the aqueous solution of sodium silicate and reacts with the aqueous solution of sodium silicate and/or polyisocyanate. In addition, JP 5-78667 A discloses a two-component type urethane foam resin as a bedrock consolidation liquid, which is a combination of Liquid A, whose main components are water and an alkali metal salt of silicate, and Liquid B, whose main component is an isocyanate prepolymer. Furthermore, JP 2016-175982 A proposes a two-component type bedrock consolidation liquid, which is made by combining Liquid A, which is prepared by blending water glass and polyol and adding water, and Liquid B, whose essential component is polyisocyanate, in which the water content in Liquid A is regulated and the ratio of water to polyol is adjusted to a specified ratio, and a dispersant is further added.

And as the polyisocyanate, which is the main component of Liquid B in these consolidation liquids, various organic isocyanate compounds having two or more isocyanate groups in the molecule or their modified products (prepolymers) can be used. However, from the standpoint of reaction activity and the strength of the resulting solidified body, aromatic polyisocyanate compounds such as diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (crude MDI), polymeric MDI, and tolylene diisocyanate (TDI) are used in practice. In particular, when liquid B, which is made using an aliphatic polyisocyanate compound such as hexamethylene diisocyanate or isophorone diisocyanate as the polyisocyanate component, is combined with liquid A as described above to make a consolidation liquid, the reaction between liquid A and liquid B is slow, and as a result, when stopping a large amount of water leakage or spring water, some of the injected liquid flows out along with the water, causing problems such as clouding and foaming of the water, which have a negative impact on the environment. In addition, the strength and flame resistance of the solidified body formed by the reaction of liquid A and liquid B are insufficient, and therefore it is not sufficient to meet the objectives of stabilizing and strengthening the ground or filling cavities.

Japanese Patent Application Publication No. 4-283290 Japanese Patent Application Publication No. 5-78667 JP 2016-175982 A

In light of the above circumstances, the inventors of the present invention have conducted various studies on consolidation liquids using aliphatic polyisocyanate compounds as polyisocyanates. As a result, they have discovered that by combining such aliphatic polyisocyanate compounds with an active hydrogen group-containing organic compound having a cyclic structure as an active hydrogen group-containing compound, and further using at least a metal carboxylate as a catalyst, all of the problems that arise when using aliphatic polyisocyanate compounds as described above can be eliminated, and have completed the present invention.

The problem to be solved by the present invention is therefore to provide a urethane-based liquid composition for consolidating ground that has excellent reactivity and causes little environmental pollution. Another problem is to provide a urethane-based liquid for consolidating ground that can form a solidified body that has high strength and excellent flexibility, and is highly tough and flame-resistant, and does not cause problems such as clouding or foaming when it comes into contact with water from leaks or springs.

The present invention can be suitably implemented in various aspects as listed below in order to solve the above problems, and each aspect described below can be adopted in any combination. It should be noted that the aspects and technical features of the present invention are not limited to those described below, but should be understood based on the inventive concept grasped from the entire description of the specification.

First, the first aspect of the present invention is a liquid composition for consolidating ground, comprising liquid A containing an active hydrogen group-containing compound and a catalyst as essential components, and liquid B containing a polyisocyanate as an essential component, wherein liquid A contains at least an active hydrogen group-containing organic compound having a cyclic structure as the active hydrogen group-containing compound, and at least a carboxylate metal salt as the catalyst, and liquid B contains at least an aliphatic polyisocyanate compound as the polyisocyanate.

In a second aspect of the present invention, the cyclic structure of the active hydrogen group-containing organic compound has an aromatic cyclic structure, an alicyclic structure, or a heterocyclic structure.

Furthermore, a third aspect of the present invention is to use a phenolic compound as the active hydrogen group-containing organic compound.

Furthermore, a fourth aspect of the present invention is to use a phenol resin as the active hydrogen group-containing organic compound.

In addition, the fifth aspect of the present invention is configured such that the proportion of cyclic structures in the active hydrogen group-containing organic compound is 15% by mass or more.

The sixth aspect of the present invention is configured such that the ratio (X/Y) of the total number of moles of active hydrogen groups in the A liquid (X) to the number of moles of isocyanate groups in the B liquid (Y) is 0.3 to 3.0.

In a seventh aspect of the present invention, the aliphatic polyisocyanate compound is a prepolymer and has a residual monomer content of less than 5% by mass.

Furthermore, in an eighth aspect of the present invention, the prepolymer of the aliphatic polyisocyanate compound is any one of an adduct, a biuret, an allophanate, and an isocyanurate derived from an aliphatic polyisocyanate compound selected from the group consisting of pentamethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, isophorone diisocyanate, and bis(isocyanatomethyl)cyclohexane.

In addition, a ninth aspect of the present invention is that a tertiary amine is further contained as a catalyst.

Furthermore, in a tenth aspect of the present invention, the liquid A and/or the liquid B further contain a flame retardant.

The eleventh aspect of the present invention is that the liquid A and the liquid B each have a viscosity of 6000 mPa·s or less at a temperature of 25°C.

According to the constitution of the liquid composition for natural ground consolidation according to the present invention, various effects as listed below can be achieved.
(1) A urethane-based ground consolidation liquid that has excellent reactivity and causes little environmental pollution is provided, and by using such a liquid, a solidified body that has high strength, excellent flexibility, toughness, and flame retardancy can be advantageously formed.
(2) After the chemical solution is injected into the ground, the hardening reaction begins immediately, which prevents the chemical solution from leaking into the environment and advantageously reduces the cloudiness and foaming of leaking water and spring water.
(3) A metal carboxylate is used as a catalyst. By using a tertiary amine catalyst in combination with this, the reaction rate is less affected even in the presence of water, and the desired solidified body can be formed quickly, thereby advantageously enhancing its practicality.
(4) By using an aliphatic polyisocyanate compound, particularly a prepolymer of an aliphatic polyisocyanate compound, as the polyisocyanate, which is an essential component of the B liquid, a strong solidified body can be advantageously formed, and pollution of the working environment at the site where the chemical solution is injected can be effectively suppressed or avoided.

In short, the present invention is a two-liquid type urethane liquid chemical composition consisting of liquid A and liquid B, in which liquid A contains an active hydrogen group-containing organic compound having a cyclic structure as the active hydrogen group-containing compound that is an essential component of liquid A, and at least a metal carboxylate as a catalyst, while liquid B contains an aliphatic polyisocyanate compound, particularly a prepolymer of an aliphatic polyisocyanate compound, as the polyisocyanate that is an essential component of liquid B. This makes it possible to effectively achieve excellent reaction activity even with an aliphatic polyisocyanate compound, and to advantageously form a high-strength solidified body, and thus has a major feature in that it has been able to advantageously achieve the intended purpose.

In the liquid A, which is one of the two liquids constituting the medicinal liquid composition according to the present invention, the active hydrogen group-containing organic compound having a cyclic structure, which is an active hydrogen group-containing compound contained as one of its essential components, is an organic compound having a cyclic structure or a cyclic structure in the molecule and having an active hydrogen group such as a hydroxyl group or an amino group. Examples of the cyclic structure include aromatic ring, alicyclic, and heterocyclic structures. Among these, aromatic ring, alicyclic, and heterocyclic compounds are preferred, and aromatic ring structures are more preferred. In particular, compounds having a structure in which a hydroxyl group or an amino group is directly bonded to an aromatic ring structure are desirable. Among these, polyfunctional compounds having two or more functional groups are more desirable. In addition, it is desirable to use a compound in which the proportion of cyclic structures in such an active hydrogen group-containing organic compound, in other words the content ratio in one molecule, is generally 15% by mass or more, preferably 25% by mass or more, and more preferably 35% by mass or more. Furthermore, it is desirable for such an active hydrogen group-containing organic compound to be a bifunctional or higher functional compound, and in addition, it is desirable for the molecular weight to be within the range of 50 to 10,000, preferably 80 to 5,000, and more preferably 100 to 3,000, which makes it possible to achieve the object of the present invention even more advantageously.

The active hydrogen group-containing organic compound having such a cyclic structure is not particularly limited, and may be appropriately selected from various known compounds, such as phenols, alcohols, amines, and thiols, having aromatic, alicyclic, or heterocyclic structures.

Specifically, phenolic compounds consisting of low molecular weight phenolic compounds such as phenol, cresol, xylenol, hydroquinone, catechol, resorcinol, pyrogallol, phloroglucinol, alkylhydroquinone, dialkylhydroquinone, trialkylhydroquinone, tetraalkylhydroquinone, dihydroxynaphthalene, and high molecular weight phenolic compounds such as bisphenol A, bisphenol F, novolac type phenolic resin, resol type phenolic resin, and benzylic ether type phenolic resin obtained by reacting phenolic compounds such as phenol and cresol with aldehydes or ketones; benzyl alcohol, methylbenzyl Aromatic alcohols such as alcohol, phenethyl alcohol, hydroxybenzyl alcohol, hydroxyphenethyl alcohol, methoxyphenylmethanol, benzenedimethanol, benzenediethanol, and 1,4-bis(α-hydroxyisopropyl)benzene; aromatic alcohols having primary and/or secondary amino groups, such as aniline, phenylenediamine, tolylenediamine, xylylenediamine, toluenediamine, methylenedianiline, diaminodiphenyl ether, trimethylphenylenediamine, diethyltoluenediamine, dimethylthiotoluenediamine, N,N'-bis(sec-butylamino)diphenylmethane, aminobenzylamine, and methylenebis( aromatic amines such as cyclohexanol, methylcyclohexanol, dimethylcyclohexanol, cyclohexanemethanol, cyclohexaneethanol, cyclobutanediol, cyclopentanediol, cyclohexanediol, cycloheptanediol, cyclooctanediol, hydroxypropylcyclohexanol, dicyclohexanediol, butylcyclohexanediol, cyclohexanedimethanol, cyclohexanediethanol, inositol, and other alicyclic alcohols; cyclohexanediamine, norbornenediamine, isophoronediamine, bis(aminomethyl) Alicyclic amines such as norbornane, bis(4-aminocyclohexyl)methane, diaminodicyclohexylmethane, and bisaminomethylcyclohexane; heterocyclic compounds such as dihydroxypyridine, sucrose, glucoside, melamine, sorbitan, and sorbitan monolaurate; hydroxyl group-containing compounds having a cyclic structure, and polyols obtained by reacting primary or secondary amines with alkylene oxides, such as polyether polyols, which are reaction products obtained by reacting ethylene oxide or propylene oxide with phenolic compounds, phenolic resins, aromatic alcohols, and cyclic sugars as initiators.

In the present invention, among the above-mentioned active hydrogen group-containing organic compounds, various phenolic compounds including low-molecular-weight and high-molecular-weight phenolic compounds are advantageously used, and among them, phenolic resins in particular are advantageously used because they have a high density of aromatic rings, which are cyclic structures, and this makes it easier for the solidified body formed to be flame-resistant and to obtain high strength. Furthermore, such phenolic resins that generally have a weight-average molecular weight in the ranges of 200 to 10,000, 300 to 5,000, or 400 to 3,000 are preferably used.

In addition, a catalyst is further used as another essential component in the A solution constituting the present invention, and in the present invention, a metal carboxylate is used as at least one of such catalysts. By using such a metal carboxylate, it is possible to increase the reaction rate in the reaction between the above-mentioned active hydrogen group-containing organic compound and the aliphatic polyisocyanate compound to a practically suitable rate. Here, the metal carboxylate, which is an essential component as one of the catalysts in the present invention, is a compound in which the hydrogen in the carboxyl group of the organic carboxylic acid is replaced with a metal such as tin, lead, zinc, iron, copper, nickel, cobalt, manganese, zirconium, or bismuth, and specific examples include tin carboxylate, lead carboxylate, zinc carboxylate, iron carboxylate, copper carboxylate, nickel carboxylate, cobalt carboxylate, manganese carboxylate, zirconium carboxylate, and bismuth carboxylate.

Among these metal carboxylates, more specific examples of tin carboxylates include tin acetate, tin butyrate, tin octylate, tin naphthenate, tin oleate, tin laurate, tin octanoate, tin dilaurate, tin dipalmitate, tin distearate, tin dioleate, tin bis(neodecanoate), tin stearate, and tin benzoate. Examples of lead carboxylates include lead acetate, lead butyrate, lead octylate, lead naphthenate, lead oleate, lead octanoate, lead neodecanoate, lead laurate, lead stearate, and lead benzoate. Examples of zinc carboxylates include zinc acetate, zinc butyrate, zinc octylate, zinc naphthenate, zinc oleate, zinc octanoate, zinc neodecanoate, zinc laurate, zinc stearate, and zinc benzoate.

In addition, examples of iron carboxylates include iron acetate, iron butyrate, iron octoate, iron naphthenate, iron oleate, iron octanoate, iron neodecanoate, iron laurate, iron stearate, and iron benzoate, while examples of copper carboxylates include copper acetate, copper butyrate, copper octoate, copper naphthenate, copper oleate, copper octanoate, copper neodecanoate, copper laurate, copper stearate, and copper benzoate. Further, examples of nickel carboxylates include nickel acetate, nickel butyrate, nickel octylate, nickel naphthenate, nickel oleate, nickel octanoate, nickel neodecanoate, nickel laurate, nickel stearate, and nickel benzoate, and examples of cobalt carboxylates include cobalt acetate, cobalt butyrate, cobalt octylate, cobalt naphthenate, cobalt oleate, cobalt octanoate, cobalt neodecanoate, cobalt laurate, cobalt stearate, and cobalt benzoate.

Furthermore, examples of manganese carboxylates include manganese acetate, manganese butyrate, manganese octylate, manganese naphthenate, manganese oleate, manganese octanoate, manganese neodecanoate, manganese laurate, manganese stearate, and manganese benzoate. Examples of zirconium carboxylates include zirconium acetate, zirconium butyrate, zirconium octylate, zirconium naphthenate, zirconium oleate, zirconium octanoate, zirconium neodecanoate, zirconium laurate, zirconium stearate, and zirconium benzoate. Examples of bismuth carboxylates include bismuth acetate, bismuth butyrate, bismuth octylate, bismuth naphthenate, bismuth oleate, bismuth octanoate, bismuth neodecanoate, bismuth laurate, bismuth stearate, and bismuth benzoate.

In particular, in the present invention, among the many metal carboxylates mentioned above, bismuth carboxylate is advantageously used because it has characteristics such as a fast reaction rate and no toxicity.

The amount of metal carboxylate used as one of such catalysts is generally selected within the range of about 0.1 to 10 parts by mass, preferably 0.3 to 5 parts by mass, per 100 parts by mass of the active hydrogen group-containing compound in Solution A, in order to effectively exert its catalytic function. If the amount of metal carboxylate used is too small, problems such as the reaction rate between the active hydrogen group-containing compound and the polyisocyanate becoming too slow can occur, while if the amount used is too large, problems such as the reaction rate becoming too fast can occur.

In addition, in addition to the above-mentioned metal carboxylate, the solution A according to the present invention may contain various other known catalysts, i.e., reaction catalysts such as tertiary amine catalysts and quaternary ammonium salts, as necessary. In the present invention, a tertiary amine catalyst is particularly advantageously used. By using such a tertiary amine catalyst in combination, the reaction rate of the chemical composition according to the present invention is less affected even in the presence of water. Therefore, at the site where the chemical composition according to the present invention is injected, the difference in reaction time between when there is substantially no water and when there is water is small.

The tertiary amine catalyst may be a foaming catalyst that promotes the reaction between polyisocyanate and water when foaming is intended upon contact with water, a resinification catalyst that promotes the reaction between polyisocyanate and polyol, or an isocyanurate catalyst that promotes the trimerization of polyisocyanate. All of these are appropriately selected from known catalysts.

Specific examples of foaming catalysts include N,N,N',N",N"-pentamethyldiethylenetriamine, N,N,N'-triethylaminoethylethanolamine, bis(dimethylaminoethyl)ether, N,N,N'-trimethylaminoethylpiperazine, N,N-dimethylaminoethoxyethanol, and triethylamine. Examples of resinification catalysts include N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetramethylpropanediamine, N,N,N',N'-tetramethylhexanediamine, triethylenediamine, 33% triethylenediamine/67% dipropylene glycol, N,N-dimethylaminohexanol, N,N-dimethylaminoethanol, N-methyl-N'-hydroxyethylpiperazine, N-methylmorpholine, 1-methylimidazole, and 1,2-dimethylimidazole. Further, examples of isocyanurate catalysts include 2,4,6-tris(dimethylaminomethyl)phenol and N,N',N"-tris(dimethylaminopropyl)-hexahydro-s-triazine. These catalysts may be used alone or in combination of two or more. Furthermore, among these, foaming catalysts or resinification catalysts are preferably used.

The amount of the tertiary amine catalyst contained in the A solution is generally determined to be 0.5 to 10 parts by mass, preferably 0.8 to 5 parts by mass, per 100 parts by mass of the active hydrogen group-containing compound. If the catalyst content is less than 0.5 parts by mass, the contribution to the reaction is reduced and it becomes difficult to sufficiently contribute to improving the reaction rate in the presence of water. If the catalyst content is more than 10 parts by mass, the reaction becomes too fast, causing problems such as difficulty in controlling the reaction rate. Furthermore, when such a tertiary amine catalyst is used together with the above-mentioned carboxylate metal salt catalyst, the ratio (mass ratio) of carboxylate metal salt: tertiary amine is generally about 5:1 to 1:5, preferably about 3:1 to 1:3.

Examples of quaternary ammonium salts include aliphatic ammonium compounds such as tetramethylammonium, methyltriethylammonium, ethyltrimethylammonium, propyltrimethylammonium, butyltrimethylammonium, pentyltrimethylammonium, hexyltrimethylammonium, heptyltrimethylammonium, octyltrimethylammonium, nonyltrimethylammonium, decyltrimethylammonium, undecyltrimethylammonium, dodecyltrimethylammonium, tridecyltrimethylammonium, tetradecyltrimethylammonium, heptadecyltrimethylammonium, hexadecyltrimethylammonium, heptadecyltrimethylammonium, and octadecyltrimethylammonium; hydroxylammonium compounds such as (2-hydroxypropyl)trimethylammonium, hydroxyethyltrimethylammonium, and trimethylaminoethoxyethanol; and alicyclic ammonium compounds such as 1-methyl-1-azania-4-azabicyclo[2,2,2]octanium, 1,1-dimethyl-4-methylpiperidinium, 1-methylmorpholinium, and 1-methylpiperidinium. Among these, tetramethylammonium, methyltriethylammonium, ethyltrimethylammonium, butyltrimethylammonium, hexyltrimethylammonium, octyltrimethylammonium, decyltrimethylammonium, dodecyltrimethylammonium, tetradecyltrimethylammonium, hexadecyltrimethylammonium, octadecyltrimethylammonium, (2-hydroxypropyl)trimethylammonium, hydroxyethyltrimethylammonium, 1-methyl-1-azania-4-azabicyclo[2,2,2]octanium, and 1,1-dimethyl-4-methylpiperidinium are preferably used because they have excellent catalytic activity and are industrially available.

The organic acid group or inorganic acid group constituting such a quaternary ammonium salt may, for example, be a formic acid group, an acetic acid group, an octylic acid group, an oxalic acid group, a malonic acid group, a succinic acid group, a glutaric acid group, an adipic acid group, a benzoic acid group, a toluic acid group, an ethylbenzoic acid group, a methylcarbonate group, a phenol group, an alkylbenzenesulfonic acid group, a toluenesulfonic acid group, a benzenesulfonic acid group, or a phosphate ester group, or an inorganic acid group such as a halogen group, a hydroxyl group, a hydrogencarbonate group, or a carbonate group. Among these, the formic acid group, the acetic acid group, the octylic acid group, the methylcarbonate group, the halogen group, the hydroxyl group, the hydrogencarbonate group, or the carbonate group is preferred because of its excellent catalytic activity and industrial availability.

On the other hand, as for the polyisocyanate, which is an essential component of liquid B, the other of the two liquids that constitute the liquid ground consolidation composition that is the subject of the present invention, in the present invention, in addition to using an aliphatic polyisocyanate compound itself, a prepolymer derived from such an aliphatic polyisocyanate compound (aliphatic polyisocyanate prepolymer) is advantageously used.

Here, examples of aliphatic polyisocyanate compounds include aliphatic diisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2-propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, methyl 2,6-diisocyanatohexanoate (lysine diisocyanate), 2-isocyanatoethyl 2,6-diisocyanatohexanoate, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6,11-triisocyanatoundecane, 1,8-diisocyanato In addition to aliphatic polyisocyanates such as aliphatic triisocyanates such as anato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, and 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyloctane, 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate), 4-methyl-1,3-cyclohexylene diisocyanate (hydrogenated TDI), 2-methyl-1,3-cyclohexylene diisocyanate, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane (hydrogenated xylylene diisocyanate) or mixtures thereof, methylene bis(4,1-cyclohexane diisocyanate), alicyclic diisocyanates such as 1,3,5-triisocyanatocyclohexane, 1,3,5-trimethylisocyanatocyclohexane, 2-(3-isocyanatopropyl)-2,5-di(isocyanatomethyl)-bicyclo(2,2,1)heptane, 2-(3-isocyanatopropyl)-2,6-di(isocyanatomethyl)-bicyclo(2,2,1)heptane, Cyclo(2,2,1)heptane, 3-(3-isocyanatopropyl)-2,5-di(isocyanatomethyl)-bicyclo(2,2,1)heptane, 5-(2-isocyanatoethyl)-2-isocyanatomethyl-3-(3-isocyanatopropyl)-bicyclo(2,2,1)heptane, 6-(2-isocyanatoethyl)-2-isocyanatomethyl-3-(3-isocyanatopropyl)-bicyclo(2,2,1)heptane ) heptane, 5-(2-isocyanatoethyl)-2-isocyanatomethyl-2-(3-isocyanatopropyl)-bicyclo(2,2,1)-heptane, 6-(2-isocyanatoethyl)-2-isocyanatomethyl-2-(3-isocyanatopropyl)-bicyclo(2,2,1)heptane, and other alicyclic polyisocyanates; 1,3- or 1,4-xylylene diisocyanate or mixtures thereof, ω,ω'-diisocyanato-1,4-diethylbenzene, 1,3- or 1,4-bis(1-isocyanato-1-methylethyl)benzene (tetramethylxylylene diisocyanate) or mixtures thereof, and other aromatic aliphatic diisocyanates, such as 1,3,5-triisocyanatomethylbenzene, and other aromatic aliphatic polyisocyanates.

The aliphatic polyisocyanate prepolymer is not particularly limited, but for example, adducts, biuret, and allophanate obtained by reacting the above-mentioned aliphatic polyisocyanate compounds such as pentamethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, bis(isocyanatomethyl)cyclohexane, and isophorone diisocyanate with active hydrogen group-containing compounds, and isocyanurates obtained by trimerizing such polyisocyanate compounds, are preferably used. Note that there is no problem even if the isocyanurate contains a dimer uretdione. In addition, isocyanurates are more preferably used for such aliphatic polyisocyanate prepolymers, taking into consideration the strength of the solidified body, flame retardancy, and other properties.

Furthermore, since such aliphatic polyisocyanate prepolymers are obtained by modifying the above-mentioned aliphatic polyisocyanate compounds, the raw material aliphatic polyisocyanate compounds remain as unreacted monomer components in the prepolymers, which are the modified products. In the present invention, such residual monomer components are preferably 5% by mass or less, and in particular, the prepolymers of aliphatic polyisocyanate compounds are prepared so that the residual monomer components are 1% by mass or less. If the residual monomer components are too high, the physical properties such as the strength of the solidified body will decrease, and the monomer components will volatilize during construction, causing problems such as a deterioration of the working environment.

The aliphatic polyisocyanate compound or its prepolymer as described above is generally contained in Liquid B at a ratio of 50 to 100% by mass, preferably 70 to 100% by mass, and more preferably 80 to 100% by mass. If the content of the aliphatic polyisocyanate compound or its prepolymer is less than 50% by mass, there is a problem that the strength of the solidified body decreases. Therefore, it is desirable that the ratio of the aliphatic polyisocyanate compound or its prepolymer in Liquid B is high, and it is also possible to constitute Liquid B only with such aliphatic polyisocyanate compound or its prepolymer. It is also possible to contain a known aromatic polyisocyanate in Liquid B in a range not exceeding 10% by mass.

Incidentally, conventional additives can be added to the above-mentioned A and B liquids consolidating the ground according to the present invention, depending on the intended use. For example, additives for A liquid can include foaming agents, foam stabilizers, flame retardants, viscosity reducers, etc. These additives for A liquid are generally used in an appropriate ratio of about 0.1 to 50 parts by mass, preferably about 0.5 to 40 parts by mass, per 100 parts by mass of the active hydrogen group-containing organic compound. Additives for the B liquid include foam stabilizers, flame retardants, viscosity reducers, etc., of which the foam stabilizer is used in an amount of 0.05 to 5 parts by mass, preferably 0.1 to 3 parts by mass, per 100 parts by mass of the polyisocyanate component, the viscosity reducer is used in an amount of 0.5 to 60 parts by mass, preferably 1 to 40 parts by mass, per 100 parts by mass of the polyisocyanate component, and the flame retardant is used in an amount of 1 to 50 parts by mass, preferably 5 to 40 parts by mass, per 100 parts by mass of the polyisocyanate component.

Of these additives, known foaming agents such as water, hydrocarbons, hydrofluorocarbons, hydrofluoroolefins, and hydrochlorofluoroolefins can be used. The foaming agent is not particularly limited, but water is preferably used. This water is also supplied from the ground to which the chemical composition is applied, and reacts with the polyisocyanate of Liquid B to generate carbon dioxide gas, thereby functioning as a foaming agent.

The foam stabilizer is used to uniformly adjust the cell structure of the foam formed by the reaction of liquid A and liquid B. Examples of the foam stabilizer include silicone, nonionic surfactants, polyoxyalkylene-modified dimethylpolysiloxane, polysiloxane oxyalkylene copolymer, polyoxyethylene sorbitan fatty acid ester, castor oil ethylene oxide adduct, lauryl fatty acid ethylene oxide adduct, etc., and among these, silicone and nonionic surfactants are preferably used. These may be used alone or in combination of two or more. Among the foam stabilizers, silicone-based foam stabilizers are more preferable, and polyoxyalkylene-modified dimethylpolysiloxane, polysiloxane oxyalkylene copolymer, etc. are preferable.

Furthermore, as the flame retardant, a liquid flame retardant or a powder flame retardant can be used. These flame retardants can be dispersed and contained in either Liquid A or Liquid B. These flame retardants can be used alone or in combination of two or more. In particular, it is preferable to use a liquid flame retardant, since it also functions as a viscosity reducer for the foamable composition. Furthermore, by using a liquid flame retardant and a powder flame retardant in combination, it is possible to further improve the flame retardancy.

Liquid flame retardants include phosphate esters and bromine-containing flame retardants, with phosphate esters being preferred because they have a low environmental impact. Examples of phosphate esters include monophosphate esters and condensed phosphate esters.

Examples of monophosphate esters include trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri(2-ethylhexyl)phosphate, tributoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, tris(isopropylphenyl)phosphate, tris(phenylphenyl)phosphate, trinaphthyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, diphenyl(2-ethylhexyl)phosphate, di(isopropylphenyl)phenyl phosphate, monoisodecyl phosphate, 2-acryloyl phosphate, Examples of such phosphates include 2-methacryloyloxyethyl acid phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, melamine phosphate, dimelamine phosphate, melamine pyrophosphate, triphenylphosphine oxide, tricresylphosphine oxide, diphenyl methanephosphonate, diethyl phenylphosphonate, resylcinol bis(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), phosphaphenanthrene, and tris(β-chloropropyl)phosphate.

Furthermore, examples of condensed phosphate esters include trialkyl polyphosphate, resorcinol polyphenyl phosphate, resorcinol poly(di-2,6-xylyl) phosphate (manufactured by Daihachi Chemical Industry Co., Ltd., product name: PX-200), hydroquinone poly(2,6-xylyl) phosphate, and condensates thereof. Examples of commercially available condensed phosphate esters other than those mentioned above include resorcinol polyphenyl phosphate (product name: CR-733S), bisphenol A polycresyl phosphate (product name: CR-741), aromatic condensed phosphate ester (product name: CR747), resorcinol polyphenyl phosphate (manufactured by ADEKA Corporation, product name: Adekastab PFR), bisphenol A polycresyl phosphate (product names: FP-600, FP-700), etc.

In addition, examples of bromine-containing flame retardants include monomeric organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromophenoxy)ethane, ethylene-bis(tetrabromophthalimide), and tetrabromobisphenol A; brominated polycarbonates such as polycarbonate oligomers produced using brominated bisphenol A as a raw material, and copolymers of the polycarbonate oligomers and bisphenol A; carboxylates; brominated epoxy compounds such as diepoxy compounds produced by the reaction of brominated bisphenol A with epichlorohydrin, and monoepoxy compounds obtained by the reaction of brominated phenols with epichlorohydrin; poly(brominated benzyl acrylate); brominated polyphenylene ether; condensates of brominated bisphenol A, cyanuric chloride, and brominated phenol; brominated polystyrenes such as brominated (polystyrene), poly(brominated styrene), and crosslinked brominated polystyrene; and halogenated bromine compound polymers such as crosslinked or non-crosslinked brominated poly(methylstyrene).

Examples of powdered flame retardants include red phosphorus, phosphate-containing flame retardants, stannate-containing flame retardants, boron-containing flame retardants, metal hydroxides, metal oxides, etc., and red phosphorus, boron-containing flame retardants, and metal hydroxides are preferably used because of ease of handling. As the red phosphorus, known red phosphorus can be used.

In this regard, examples of the phosphate-containing flame retardant include phosphates such as monophosphates, pyrophosphates, polyphosphates, etc. Examples of the monophosphates include ammonium salts such as ammonium phosphate, ammonium dihydrogen phosphate, and diammonium hydrogen phosphate; sodium salts such as monosodium phosphate, disodium phosphate, trisodium phosphate, monosodium phosphite, disodium phosphite, and sodium hypophosphite; potassium salts such as monopotassium phosphate, dipotassium phosphate, tripotassium phosphate, monopotassium phosphite, dipotassium phosphite, and potassium hypophosphite; lithium salts such as monolithium phosphate, dilithium phosphate, trilithium phosphate, monolithium phosphite, dilithium phosphite, and lithium hypophosphite; barium salts such as barium dihydrogen phosphate, barium hydrogen phosphate, tribarium phosphate, and barium hypophosphite; magnesium salts such as monohydrogen magnesium phosphate, magnesium hydrogen phosphate, trimagnesium phosphate, and magnesium hypophosphite; calcium salts such as calcium dihydrogen phosphate, calcium hydrogen phosphate, tricalcium phosphate, and calcium hypophosphite; and zinc salts such as zinc phosphate, zinc phosphite, and zinc hypophosphite. Examples of polyphosphates include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium amide polyphosphate, and aluminum polyphosphate.

Examples of stannate-containing flame retardants include zinc stannate, barium stannate, sodium stannate, potassium stannate, cobalt stannate, magnesium stannate, etc.

Furthermore, examples of boron-containing flame retardants include borax, boron oxide, boric acid, and borate salts. Specific examples of boron oxide include diboron trioxide, boron trioxide, diboron dioxide, tetraboron trioxide, and tetraboron pentoxide. Examples of borates include alkali metal borate salts such as lithium borate, sodium borate, potassium borate, and cesium borate; alkaline earth metal borate salts such as magnesium borate, calcium borate, and barium borate; zirconium borate, zinc borate, aluminum borate, and ammonium borate.

Examples of metal hydroxides include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, and tin hydroxide. In addition, examples of metal oxides include zinc oxide, aluminum oxide, and titanium oxide.

In addition, the viscosity reducer is used as a solvent, and is dissolved in liquid A or liquid B to reduce the viscosity of those liquids. As long as it has such a function, there are no particular limitations on the type of viscosity reducer, and examples of such viscosity reducers include alcohols such as methanol and ethanol, ethers such as ethyl cellosolve and butyl cellosolve, cyclic esters such as propylene carbonate, esters such as dicarboxylic acid methyl esters and ethylene glycol monomethyl ether acetate, petroleum hydrocarbons, etc. These may be used alone or in combination of two or more types.

Meanwhile, the A and B liquids prepared according to the present invention are adjusted so that their viscosities at 25°C are 6000 mPa·s or less, preferably 10 to 5000 mPa·s, and more preferably 20 to 3500 mPa·s. If the viscosity is higher than 6000 mPa·s, the A and B liquids become viscous, and the fluidity during mixing is poor, as well as the fluidity during pumping is poor, which may cause problems such as an increase in injection pressure. If the viscosity is lower than 20 mPa·s, the A and B liquids are easily diluted with water, which may cause problems such as clouding of the wastewater. In addition, the temperature of the A and B liquids may be adjusted using a heater to reduce the viscosity when pumped, and it is also possible to heat them to 0 to 50°C depending on the outside air temperature.

In addition, when using the liquid composition for natural ground consolidation according to the present invention, which is composed of such liquid A and liquid B, the two liquids are mixed at the time of use, injected into the target natural ground, ground, rock, etc. according to a known method, and reacted and hardened to form a high-strength solidified body. The mixing ratio of liquid A and liquid B is appropriately changed depending on the total content (total number of moles: X) of active hydrogen groups (OH groups, _NH2 groups) in liquid A that will be introduced by the active hydrogen group-containing organic compound having a cyclic structure, and the content (number of moles: Y) of isocyanate groups (NCO groups) in liquid B that will be introduced by polyisocyanate, but is generally adopted in the range of X/Y = 0.3 to 3.0, preferably 0.3 to 2.8, more preferably 0.4 to 2.4 in terms of molar ratio. If the molar ratio (X/Y) is less than 0.3, it becomes difficult to impart sufficient strength to the formed solidified body, and there is a risk that the natural ground cannot be sufficiently improved. On the other hand, if the molar ratio is more than 3.0, the reaction does not proceed sufficiently, and the strength and flexibility of the solidified body may be insufficient.

In this way, when mixing liquid A and liquid B according to the present invention, the mixing ratio (A:B) is appropriately determined taking into consideration the active hydrogen group content in liquid A and the isocyanate group content in liquid B, but generally, a ratio of A:B of 2:1 to 1:3, preferably 1:1 to 1:2, is adopted on a mass basis. There are also no particular limitations on the method of using liquid A and liquid B, so long as the method ensures that the two liquids are mixed immediately before use, and any of the various conventionally known injection methods may be appropriately adopted.

Furthermore, the reaction time (the time from mixing to hardening) when liquid A and liquid B are mixed is preferably within 600 seconds when the liquid temperature is 25°C, and more preferably 20 to 360 seconds. If the reaction time is longer than 600 seconds, problems such as the liquid flowing out into the spring water after being injected into the ground and before it hardens can occur, causing the water to become cloudy or foam. If the reaction time is too short, for example, shorter than 20 seconds, the reaction will proceed too quickly, causing problems such as blocking the liquid injection pipe and making it difficult to fully penetrate the ground.

Below, we will present some examples and comparative examples of the present invention to clarify the present invention in more detail, but it goes without saying that the present invention is not limited in any way by the description of such examples. Furthermore, it should be understood that in addition to the examples below and the specific description above, various changes, modifications, improvements, etc. can be made to the present invention based on the knowledge of those skilled in the art, as long as they do not deviate from the spirit of the present invention.

In addition to the properties (viscosity) of the A and B liquids obtained in the following examples and comparative examples, the mixability of the A and B liquids when mixed, the degree of cloudiness of the water after the A and B liquids are reacted and foamed in water, the reaction time when the A and B liquids are mixed and reacted and hardened, the compressive strength and flexural strength of the reaction product, the foaming ratio in the presence/absence of water, and the oxygen index of the reaction product were each measured or evaluated according to the following methods. In addition, the "%", "ratio", and "parts" shown below are all based on mass.

(1) Viscosity Measurement The viscosities of the A and B liquids obtained in the Examples and Comparative Examples were measured using a B-type viscometer in accordance with JIS-K-7117-1:1999.

(2) Evaluation of Mixability Liquid A and liquid B adjusted to a temperature of 25°C were placed in a 300 ml cup at a mixing ratio specified in each Example and Comparative Example to make a total of 100 parts, and immediately mixed with a spatula for 20 seconds, and the state of the mixture was observed from the start of mixing to after mixing. The mixture was evaluated as follows: ◯ if liquid A and liquid B were sufficiently mixed after 20 seconds, △ if the mixture was slightly insufficient due to thickening during mixing, and × if the mixture was not sufficient due to thickening during mixing and there was unevenness in the solidified product.

(3) Evaluation of turbidity The A and B liquids, each adjusted to a temperature of 25°C, were weighed and mixed in a total amount of 100 ml at the mixing ratio adopted in each Example and Comparative Example. Then, immediately after the mixing, the mixture of the A and B liquids was poured into 1 L of water at 25°C contained in a 2 L disc cup, and allowed to stand until the reaction subsided. After the reaction was completed, the state of the water was visually observed, and the evaluation was performed as follows: ○ if no turbidity was observed immediately after the reaction subsided, △ if turbidity was not observed within 1 hour after the reaction subsided, and × if turbidity was observed even after 1 hour or more had passed after the reaction subsided.

(4) Measurement of reaction time Liquid A and liquid B adjusted to a temperature of 25° C. were mixed in a mixing ratio adopted in each of the Examples and Comparative Examples to initiate the reaction. The reaction time was determined as the time until gas was generated from the reaction product and the foam height no longer changed, or the time until a skewer could no longer be pierced into the reaction product, whichever was later.

(5) Compressive Strength Test/Flexural Strength Test Liquid A and liquid B adjusted to a temperature of 25° C. were weighed and mixed in a total amount of 100 ml at the mixing ratio adopted in each Example and Comparative Example. Then, immediately after such mixing, a predetermined amount of the mixture of liquid A and liquid B was poured into a bottomed cylindrical mold with an inner diameter of 50 mm and a height of 100 mm, and after closing the lid, curing was performed for 2 hours or more. Thereafter, the reaction product removed from the mold was cured at a temperature of 25° C. for 24 hours or more, and the compressive strength was measured in accordance with JIS-K-7220:2006.

The bending strength was measured in accordance with JIS-K-7221:2006 using test specimens made of the reaction product obtained in the same manner as above.

(6) Measurement of Expansion Ratio Liquid A and liquid B adjusted to a temperature of 25°C were weighed out in the mixing ratio adopted in each Example and Comparative Example so that the total amount was 100 ml, and these were placed in a 2 L disc cup and thoroughly mixed and stirred to harden. Then, the foam height of the reaction product after the hardening reaction was measured to obtain the expansion ratio.

(7) Measurement of reaction time and expansion ratio in the presence of water To the solution A in each of the examples and comparative examples, 0.5 parts of a foam stabilizer: B8450 (manufactured by Evonik) and 2 parts of water were further added, and the reaction time and expansion ratio in the presence of water were determined in the same manner as in the above (4) Measurement of reaction time and (6) Measurement of expansion ratio.

(8) Evaluation of oxygen index (flame retardancy) 0.5 parts of foam stabilizer: B8450 (manufactured by Evonik) and 2 parts of water were further added to the A liquid adjusted to a temperature of 25 ° C. in each example and comparative example, and the B liquid adjusted to a temperature of 25 ° C. was mixed with this in the ratio adopted in each example and comparative example, and immediately poured into a 250 mm × 100 mm × 50 mm mold in an amount that would result in 3 times the foaming, and then, after covering, curing for 2 hours or more. After that, the mold was removed and cured at 25 ° C. for 24 hours or more, and then a test specimen was cut out from the obtained reaction product, and the oxygen index of each test specimen was measured in accordance with JIS-K-7201-2:2007. Note that the larger the oxygen index, the better the flame retardancy.

First, the following various raw materials were prepared as components of the A and B solutions used in the following examples and comparative examples.
Polyol: Phenolic resin (prepared according to the synthesis method below)
Resorcinol (Tokyo Chemical Industry Co., Ltd., aromatic ring content: 69%)
PF300 [Asahi Organic Chemicals Co., Ltd., phenolic resin polyol (EOPO adduct), aromatic ring content: 46%]
Cyclohexanedimethanol (manufactured by Sanyo Chemical Industries, Ltd., 1,4-cyclohexanedimethanol, alicyclic content: 57%)
: Sorbitan monolaurate (Fujifilm Wako Pure Chemical Industries, Ltd., Sorbitan monolaurate, heterocyclic content: 20%)
: PP-400 [Sanyo Chemical Industries, Ltd., Sannix PP-2000 (
Polyether polyol, molecular weight 400, functional group number 2), no cyclic structure]
: 450ED [AGC Co., Ltd., Excelol 450ED (polyether polyol, molecular weight 400, functional group number 4), does not contain a cyclic structure]
Polyamine: diethyltoluenediamine (Albemarle Corporation, Ethacure 100, aromatic ring content: 41%)
Catalyst: Bismuth catalyst (manufactured by Nippon Chemical Industry Co., Ltd., bismuth octylate, bismuth concentration: 2.5%)
: Tin catalyst (Nihon Kagaku Sangyo Co., Ltd., dibutyltin dioctate)
: Kao Raiser No. 26 (Kao Corporation, tertiary amine catalyst)
: Kao Raiser No. 390 (Kao Corporation, tertiary amine catalyst)
Viscosity reducer: PC (Tokyo Chemical Industry Co., Ltd., propylene carbonate)
: DOP (Tokyo Chemical Industry Co., Ltd., dioctyl phthalate)
Flame retardant: Phosphate ester (Daihachi Chemical Industry Co., Ltd., tris(chloropropyl)phosphate)
：Red phosphorus (Nova Excel 140, manufactured by Rinkagaku Kogyo Co., Ltd.)
: Phosphinate (Clariant Chemicals, EXOLIT OP-935)
: Aluminum hydroxide (Nippon Light Metal Co., Ltd., Aluminum hydroxide)
Polyisocyanate: HDI nurate (Mitsui Chemicals, Takenate D-170N, hexamethylene diisocyanate prepolymer, nurate type, NCO ratio: 21%)
: HDI biuret (manufactured by Mitsui Chemicals, Inc., Takenate D-165N, hexamethylene diisocyanate prepolymer, biuret type, NCO ratio: 23.5%)
: PDI nurate (manufactured by Mitsui Chemicals, Inc., Stabio D-476N, pentamethylene diamine prepolymer, mixture of nurate type/allophanate type, NCO ratio: 23.5%)
: XDI (Mitsui Chemicals, Takenate 500, xylylene diisocyanate, NCO ratio: 47%)
: MDI (Kinko Mitsui Chemicals, Cosmonate M-200, polymeric MDI, NCO ratio: 31%)

- Synthesis of phenolic resin -
In a three-necked reaction flask equipped with a reflux condenser, a thermometer, and a stirrer, 50 parts of phenol and 50 parts of orthocresol (phenol/orthocresol=50/50) were charged together with 51.9 parts of 92% paraformaldehyde and 0.15 parts of zinc naphthenate as a divalent metal salt, and the mixture was reacted at reflux temperature for 90 minutes. The mixture was then washed with 100 parts of water to remove the water layer, and then heated and concentrated to obtain a phenolic resin (orthocresol modified benzyl ether type phenolic resin) with a water content of 1% or less. The synthesized phenolic resin had a free phenol content of 1% or less and a formaldehyde content of 0.1% or less. The aromatic ring content was 65%.

(Examples 1 to 19)
- Preparation of solution A -
The various raw materials prepared above, i.e., active hydrogen group-containing organic compounds (polyol, polyamine), catalyst, viscosity reducer, and flame retardant, were uniformly mixed in the various combinations and blending ratios shown in Tables 1 and 2 below to prepare various A-liquid blend compositions according to Examples 1 to 20. The viscosities of the obtained A-liquid blend compositions were then measured, and the results are shown in Tables 1 and 2 below.

- Preparation of solution B -
Using each of the polyisocyanates prepared above, a liquid B blend composition consisting of 100% of each of the polyisocyanates was prepared. The viscosity of each of the liquid B blend compositions was measured, and the results are shown in Tables 1 and 2 below.

-Reaction of solution A and solution B-
The A and B solutions obtained above were combined in the ratios shown in Tables 1 and 2, and were uniformly mixed and reacted at room temperature. Various evaluation tests were then carried out according to the evaluation methods described above, and the results are shown in Tables 1 and 2 below.

(Comparative Example 1)
The tests were carried out in the same manner as in Example 2, except that no bismuth catalyst was added as the catalyst in Example 2. The results are shown in Table 2 below.

(Comparative Example 2)
The tests were carried out in the same manner as in Example 2, except that a polyether polyol (450ED) not having a cyclic structure was used instead of the phenol resin in Example 2. The results are shown in Table 2 below.

(Comparative Example 3)
Tests were carried out in the same manner as in Example 2, except that MDI, which is an aromatic polyisocyanate and not an aliphatic polyisocyanate compound, was used instead of HDI nurate used as the polyisocyanate component in Example 2. The results are shown in Table 2 below.

As is clear from the results in Tables 1 and 2, the liquid chemical compositions in Examples 1 to 20, which are made of Liquid A and Liquid B according to the present invention, all have excellent reaction activity with a reaction time of 600 seconds or less, good mixability, and can form solidified bodies with high compressive strength and bending strength, and also show good results in the cloudiness test.

In contrast, among the liquid chemical compositions prepared in Comparative Examples 1 to 3, consisting of liquid A and liquid B, the liquid chemical composition according to Comparative Example 1 was found to take a long time for the hardening reaction, to have poor reactivity, and to have poor compressive strength and bending strength of the solidified body. The liquid chemical composition according to Comparative Example 2 was found to have poor results in the cloudiness test, and the liquid chemical composition according to Comparative Example 3 was found to have poor mixability, and to have poor compressive strength and bending strength of the solidified body obtained.

- Change in reaction time and foaming ratio in the presence of water -
Using the liquid chemical compositions prepared in Example 1, Examples 5 to 7, Example 11, Examples 16 to 17, and Comparative Examples 1 to 3, 0.5 parts of a foam stabilizer: B8450 (manufactured by Evonik) and 2 parts of water were further added to each of the liquid A components, and the components were mixed with liquid B to react, and the reaction time and the expansion ratio were investigated, and the results are shown in the following Table 3. For reference, the results shown in Tables 1 and 2 obtained by reacting liquid A with liquid B in the absence of water are shown in Table 4 as the reaction time and expansion ratio in the absence of water.

As is clear from the results in Table 3, in the liquid chemical compositions of each Example according to the present invention, the rate of change (times) of reaction time in the presence of water relative to the reaction time in the absence of water is small, which indicates that the reaction between Liquid A and Liquid B is less susceptible to the effects of water. In contrast, in Comparative Examples 2 and 3, the rate of change of reaction time in the presence of water is large, which indicates that the reaction between Liquid A and Liquid B is significantly affected by water.

- Examination of flame retardancy based on oxygen index -
The oxygen index of each of the foamed products (solidified bodies) obtained by foaming and curing the A and B liquids prepared in Examples 4 to 8, Examples 21 to 23, and Comparative Example 2 was measured, and the results are shown in Table 4 below.

As is clear from the results in Table 4, the liquid chemical compositions of Examples 4 to 8 and Examples 21 to 23, which are made of Liquid A and Liquid B according to the present invention, have a larger oxygen index than the foamed solid obtained from the liquid chemical composition of Comparative Example 2, and this indicates that they provide a foamed solid with good flame retardancy.

Claims (12)

A liquid composition for natural ground consolidation comprising liquid A containing an active hydrogen group-containing compound and a catalyst as essential components, and liquid B containing a polyisocyanate as an essential component,
The liquid composition for consolidating ground is characterized in that the liquid A contains at least an active hydrogen group-containing organic compound having a cyclic structure as the active hydrogen group-containing compound, and at least a metal salt of a carboxylic acid (excluding an alkali metal salt of a fatty acid) as the catalyst, and the liquid B contains at least an aliphatic polyisocyanate compound as the polyisocyanate. The liquid composition for consolidating natural ground according to claim 1, characterized in that the cyclic structure of the active hydrogen group-containing organic compound is an aromatic cyclic structure, an alicyclic structure, or a heterocyclic structure. The liquid composition for consolidating natural ground according to claim 1 or 2, characterized in that the active hydrogen group-containing organic compound is a phenol-based compound. The liquid composition for consolidating natural ground according to claim 1 or 2, characterized in that the active hydrogen group-containing organic compound is a phenolic resin. The liquid composition for consolidating natural ground according to any one of claims 1 to 4, characterized in that the proportion of cyclic structures in the active hydrogen group-containing organic compound is 15 mass% or more. A liquid composition for natural ground consolidation comprising liquid A containing an active hydrogen group-containing compound and a catalyst as essential components, and liquid B containing a polyisocyanate as an essential component,
A liquid composition for consolidating natural ground, characterized in that the A liquid contains at least a phenolic resin as the active hydrogen group-containing compound and at least a carboxylic acid metal salt as the catalyst, and the B liquid contains at least an aliphatic polyisocyanate compound as the polyisocyanate. The liquid composition for natural ground consolidation according to any one of claims 1 to 6, characterized in that the ratio (X/Y) of the total number of moles of active hydrogen groups in the A liquid (X) to the number of moles of isocyanate groups in the B liquid (Y) is 0.3 to 3.0. The liquid composition for consolidating natural ground according to any one of claims 1 to 7, characterized in that the aliphatic polyisocyanate compound is a prepolymer and has a residual monomer content of less than 5 mass%. The liquid composition for consolidating natural ground according to claim 8, characterized in that the prepolymer of the aliphatic polyisocyanate compound is any one of an adduct, a biuret, an allophanate, and an isocyanurate derived from an aliphatic polyisocyanate compound selected from the group consisting of pentamethylene diisocyanate, hexamethylene diisocyanate, octamethylene diisocyanate, isophorone diisocyanate, and bis(isocyanatomethyl)cyclohexane. The liquid composition for consolidating natural ground according to any one of claims 1 to 9, characterized in that the liquid A further contains a tertiary amine as a catalyst. The liquid composition for consolidating natural ground according to any one of claims 1 to 10, characterized in that the liquid A and/or the liquid B further contain a flame retardant. The liquid composition for rock mass consolidation according to any one of claims 1 to 11, characterized in that the liquid A and the liquid B each have a viscosity of 6000 mPa·s or less at a temperature of 25°C.