Chemical liquid composition for ground injection

Abstract

To provide a chemical composition for ground injection capable of showing stable foaming property even under low temperature.SOLUTION: In a chemical composition for ground injection comprising liquid A containing silicate aqueous solution and a tertiary amine catalyst as essential components, and liquid B containing polyisocyanate as an essential component, in the liquid A, in addition, a primary and / or secondary amino group-containing compound, and organic or inorganic acid are added or contained, individually or in the form of each reaction product.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a chemical solution composition for ground injection, and particularly relates to a technique for improving the low-temperature foaming characteristics of a two-component chemical solution composition for ground injection, which comprises a liquid A containing an aqueous silicate solution and a tertiary amine catalyst as essential components, and a liquid B containing a polyisocyanate as an essential component.

Background Art

[0002] Conventionally, as one of the measures adopted in ground improvement applications for stabilizing unstable rock formations or ground, and in cavity filling applications for filling cracks and voids in artificial structures, a method of injecting inorganic or organic grout to consolidate the ground, etc. is known. For example, a method of using a foaming polyurethane material formed by combining a polyol and a polyisocyanate, injecting it, and causing it to foam and cure has been adopted.

[0003] By the way, in the consolidation method by injecting such a foaming polyurethane material, since a foamed cured body mainly composed of an organic substance (resin) is generated by the urethanization reaction between the polyol and the polyisocyanate, problems such as the occurrence of a fire due to fire are inherent, and also, since the material itself is expensive, problems such as a soaring construction cost are also inherent.

[0004] Therefore, in Japanese Patent Laid-Open No. 5-78667, Japanese Patent Laid-Open No. 2004-075754, etc., an injection chemical solution comprising a liquid A mainly composed of an aqueous alkali silicate solution, which is cheaper in material cost than conventional polyol-based organic substances, and a liquid B mainly composed of a polyisocyanate is proposed. By injecting these two liquids and causing them to foam and cure, a composite foamed cured body of an inorganic substance and an organic substance is formed, and it has been clarified that a higher flame retardancy than that of conventional foaming polyurethane materials can be exhibited.

[0005] However, in the case of the injection chemical solution composed of the liquid A and the liquid B, during construction in winter, the chemical solution may be cooled by the outside air temperature to a low temperature that does not reach even about 0°C to 15°C, which may have an adverse effect on the consolidation work of the ground. That is, in such a low temperature, when the liquid A and the liquid B are mixed and reacted, even if a tertiary amine is used as a catalyst, the reaction becomes slow. Further, when a primary and / or secondary amino group-containing compound serving as a crosslinking agent is added, it reacts with the polyisocyanate first, and the crosslinking of the reaction product is promoted. Therefore, there is an inherent problem that the foaming of the reaction product is inhibited, and it becomes difficult to obtain an effective foamed cured body.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] Here, the present invention has been made against the background of the above circumstances, and the problem to be solved is to provide a chemical solution composition for ground injection that can exhibit stable foaming characteristics even at low temperatures. Another problem is to provide a two-component chemical solution composition for ground injection composed of a liquid A containing an aqueous silicate solution and a tertiary amine catalyst as essential components and a liquid B containing a polyisocyanate as an essential component. Even for a foam (reaction product) formed by allowing the reaction to proceed at a low temperature, to provide a technique capable of enhancing the foaming stability in such a foam while advantageously ensuring its strength and obtaining a foam having excellent compressive strength.

Means for Solving the Problems

[0008] Then, in order to solve the above-described problems, the present invention can be preferably implemented in various aspects listed below. Moreover, each of the aspects described below can be adopted in any combination. It should be considered that the aspects or technical features of the present invention are not limited to those described below, and should be understood based on the inventive concept grasped from the description of the entire specification.

[0009] First, in order to solve the above-described problems, the present invention provides a chemical solution composition for ground injection comprising a liquid A containing an aqueous silicate solution and a tertiary amine catalyst as essential components, and a liquid B containing a polyisocyanate as an essential component. The liquid A further contains a primary and / or secondary amino group-containing compound and an organic or inorganic acid, either individually or in the form of a reaction product thereof. This is the first aspect of the chemical solution composition for ground injection.

[0010] In addition, in the second aspect of the present invention, a polyamine compound having two or more primary and / or secondary amino groups in one molecule is used as the primary and / or secondary amino group-containing compound.

[0011] Furthermore, according to the third aspect of the present invention, the primary and / or secondary amino group-containing compound is an aromatic amine compound.

[0012] In addition, in the fourth aspect of the present invention, the primary and / or secondary amino group-containing compound is added and contained in a proportion of 0.01 to 20 parts by mass with respect to 100 parts by mass of the polyisocyanate.

[0013] Then, in the fifth aspect of the present invention, the primary and / or secondary amino group-containing compound and the organic or inorganic acid are added and contained in a proportion such that the mixing ratio (P) represented by the following formula is 0.3 to 2.5. P = [amount of functional groups of organic or inorganic acid per 1 g × amount of addition of organic or inorganic acid] / (Functional group amount of primary and / or secondary amino group-containing compound per 1 g × Amount of primary and / or secondary amino group-containing compound added)

[0014] Further, a sixth aspect of the present invention is characterized in that the tertiary amine catalyst has an alcoholic hydroxyl group.

[0015] Furthermore, a seventh aspect of the present invention is characterized in that the liquid A further contains a polyol.

[0016] In addition, an eighth aspect according to the present invention is characterized in that the liquid A and the liquid B each have a viscosity of 400 mPa·s or less at a temperature of 25°C.

Advantages of the Invention

[0017] Thus, in the chemical liquid composition for ground injection according to the present invention, in the liquid A, as its essential components, a primary and / or secondary amino group-containing compound and an organic or inorganic acid are further added and contained individually or in the form of their reaction product. Therefore, the reaction between the liquid A and the liquid B can proceed effectively. Even during construction at a low temperature (about 0 to 15°C) in winter, the reaction of the primary and / or secondary amino group-containing compound with the polyisocyanate can be effectively delayed by the organic or inorganic acid. As a result, the promotion of crosslinking and foaming can proceed simultaneously, and a good foamed cured body can be obtained even at a low temperature.

[0018] In short, according to the configuration of the chemical liquid composition for ground injection according to the present invention, it is possible to obtain a good foam by foaming while advantageously ensuring the strength of the reaction product generated during the reaction between the liquid A and the liquid B. In particular, the foam stability under a low temperature environment such as in winter can be effectively improved, and the compressive strength of the reaction product, which is a foam generated by the reaction, can be advantageously increased.

Embodiments for Carrying Out the Invention

[0019] Incidentally, in the two-component urethane-based chemical solution composition composed of liquid A and liquid B, in such liquid A, in addition to the aqueous silicate solution which is an essential component, a tertiary amine is used as a catalyst, and further, in a form used in combination with such a tertiary amine catalyst, a primary and / or secondary amino group-containing compound and an organic or inorganic acid are added and contained individually or in the form of their reaction product, whereby the reaction between liquid A and liquid B can be effectively advanced even under a low-temperature environment, and a cured reaction product (foam) can be formed more stably. Thus, since the intended purpose can be advantageously achieved, it has a great feature.

[0020] And, in liquid A which is one of the two liquids constituting the chemical solution composition according to the present invention, the aqueous silicate solution contained as one of its essential components is an aqueous solution of a soluble silicate compound, which is also called so-called water glass. Here, examples of such a silicate compound include sodium silicate, potassium silicate, sodium metasilicate, potassium metasilicate, lithium silicate, ammonium silicate, etc. Among them, in the present invention, sodium silicate (sodium silicate), which is easily available and inexpensive, is preferably used. And when using sodium silicate, the molar ratio of SiO2 / Na2O is desirably in the range of 2.0 to 4.0. When this molar ratio becomes smaller than 2.0, the compatibility with additives such as primary and / or secondary amino group-containing compounds and reaction catalysts deteriorates, and gel-like substances are likely to be generated, so that long-term storage becomes difficult. Further, when the molar ratio becomes larger than 4.0, there is a risk of causing problems such as a decrease in the dispersion stability of the liquid, a further increase in the freezing point, and inability to be used in winter.

[0021] Incidentally, various types of sodium silicate aqueous solutions, i.e., water glass as described above, are commercially available, and in the present invention, such commercially available products can be appropriately selected and used. Regarding the aqueous solution of sodium silicate, it is defined by the JIS standard (JIS K 1408) and is known as No. 1, No. 2, No. 3, etc. However, as long as it is formulated in accordance with this JIS standard, those with formulations such as No. 4, No. 5, 1.5, 2.5, etc. can also be used. Furthermore, the proportion of the solid component in the water glass in the form of such an aqueous solution varies depending on each grade of the JIS standard, the type of water glass, etc. From the viewpoints of the stability and solidification characteristics of the A liquid, generally, it is about 20 to 60% by mass, and preferably, water glass containing a solid component at a proportion of 30 to 50% by mass is advantageously used.

[0022] In addition, such an A liquid contains a catalyst for promoting the reaction with the B liquid as an essential component. In the present invention, in particular, a tertiary amine catalyst is advantageously used.

[0023] Here, as the tertiary amine catalyst, in the case where foaming is intended by contact with water, there are a foaming catalyst having an action of promoting the reaction between polyisocyanate and water, a resinification catalyst having an action of promoting the reaction between polyisocyanate and polyol, and further an isocyanurate formation catalyst having an action of promoting the trimerization of polyisocyanate, etc. All of them will be appropriately selected from known ones.

[0024] Specifically, examples of the foaming catalyst include N,N,N’,N”,N”-pentamethyldiethylenetriamine (molecular weight: 173.3, boiling point: 198 °C), N,N,N’-trimethylaminoethylethanolamine (molecular weight: 146.2, boiling point: 207 °C), bis(dimethylaminoethyl) ether (molecular weight: 160.3, boiling point: 189 °C), N,N,N’-trimethylaminoethylpiperazine (molecular weight: 171.3, boiling point: 96 °C / 12 mmHg), N,N-dimethylaminoethoxyethanol (molecular weight: 133.2, boiling point: 95 °C / 15 mmHg), triethylamine (molecular weight: 101.2, boiling point: 89.3 °C), and the like. Examples of the resinification catalyst include N,N,N’,N’-tetramethylethylenediamine (molecular weight: 116.2, boiling point: 120 °C), N,N,N’,N’-tetramethylpropanediamine (molecular weight: 130.2, boiling point: 145 °C), N,N,N’,N’-tetramethylhexamethylenediamine (molecular weight: 172.3, boiling point: 210 °C), triethylenediamine (molecular weight: 112.2, boiling point: 174 °C), 33% triethylenediamine·67% dipropylene glycol (molecular weight: 112.2, boiling point: 199 °C), N,N-dimethylaminohexanol (molecular weight: 145.3, boiling point: 117 °C / 12 mmHg), N,N-dimethylaminoethanol (molecular weight: 89.1, boiling point: 133 °C), N-methyl-N’-hydroxyethylpiperazine (molecular weight: 144.2, boiling point: 55 °C / 1.5 mmHg), N-methylmorpholine (molecular weight: 101.2, boiling point: 116 °C), 1-methylimidazole (molecular weight: 82.1, boiling point: 198 °C), 1,2-dimethylimidazole (molecular weight: 96.1, boiling point: 205 °C), and the like. Further, examples of the isocyanuration catalyst include 2,4,6-tris(dimethylaminomethyl)phenol (molecular weight: 265.4, boiling point: 135 °C / 1 mmHg), N,N’,N”-tris(dimethylaminopropyl)-hexahydro-s-triazine (molecular weight: 342.6, boiling point: 141 °C), and the like.

[0025] These catalysts can be used alone or in combination of two or more without any problem. Further, among these, a foaming catalyst or a resinifying catalyst is preferably used. In particular, among these tertiary amines, those having an alcoholic hydroxyl group are advantageously used in better achieving the object of the present invention. Further, when the molecular weight of such a tertiary amine is low, it is likely to volatilize, and problems such as generating odor due to the heat of reaction during foaming or the temperature in the construction environment will occur. Therefore, a tertiary amine having a molecular weight of 104 or more, preferably 110 or more, is preferably used. Further, in order to suppress the generation of odor caused by the heat of reaction during foaming, a tertiary amine having a boiling point of 100 ° C or more at normal pressure is advantageously used.

[0026] Incidentally, the amount of the tertiary amine as a catalyst contained in such a liquid A is generally appropriately determined in a proportion of 0.05 to 5 parts by mass, preferably 0.1 to 3 parts by mass, based on 100 parts by mass of the polyisocyanate. When the content of the tertiary amine as this catalyst is less than 0.05 part by mass, there is a problem that the contribution to the reaction decreases and the strength of the reaction product cannot be sufficiently ensured. On the other hand, when it exceeds 5 parts by mass, the reaction proceeds too much, causing an abnormal reaction, the chemical liquid solidifies during the injection operation, and it becomes difficult to perform sufficient foaming.

[0027] In addition, if necessary, such Solution A may appropriately contain, as a catalyst, in addition to the above-mentioned tertiary amine, known metal catalysts, quaternary ammonium salt catalysts, and the like. Among them, as the metal catalyst, known ones can be used without particular limitation. For example, organic acid metal salts and organometallic complexes of sodium, potassium, calcium, tin, lead, bismuth, zinc, iron, nickel, zirconium, cobalt, etc. can be used. Among them, as the organic acid metal salt, salts of acetic acid, octylic acid, neodecanoic acid, naphthenic acid, rosin acid, etc. with the above metals can be mentioned, and as the organometallic complex, complexes of acetylacetone, etc. with the above metals can be mentioned. Specifically, sodium acetate, potassium acetate, potassium octylate, bismuth octylate, lead octylate, iron octylate, tin octylate, calcium octylate, zinc octylate, zirconium octylate, bismuth neodecanoate, zinc neodecanoate, lead neodecanoate, cobalt neodecanoate, dibutyltin dioctate, dibutyltin dilaurate; iron acetylacetonate, zinc acetylacetonate, zirconium acetylacetonate, nickel acetylacetonate, tin acetylacetonate, etc. can be mentioned. These metal salts and metal complexes may be used after being dissolved in diluents such as mineral spirits, organic acids, glycols, esters, etc. for improving their handleability. In addition, these metal catalysts may be used alone or in combination of two or more. Among these, preferably, acetates, octylates, neodecanoates, laurates of potassium, tin, lead, bismuth or zinc, and acetylacetone complexes can be mentioned, and more preferably, catalysts using potassium, tin, bismuth as metals are preferably used.

[0028] In addition, examples of the quaternary ammonium salts include aliphatic ammonium compounds such as tetramethylammonium, methyltriethylammonium, ethyltrimethylammonium, propyltrimethylammonium, butyltrimethylammonium, pentyltrimethylammonium, hexyltrimethylammonium, heptyltrimethylammonium, octyltrimethylammonium, nonyltrimethylammonium, decyltrimethylammonium, undecyltrimethylammonium, dodecyltrimethylammonium, tridecyltrimethylammonium, tetradecyltrimethylammonium, hexadecyltrimethylammonium, heptadecyltrimethylammonium, and octadecyltrimethylammonium; hydroxyammonium compounds such as (2-hydroxypropyl)trimethylammonium, hydroxyethyltrimethylammonium, and trimethylaminoethoxyethanol; and alicyclic ammonium compounds such as 1-methyl-1-azanium-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-azanium-4-azabicyclo[2,2,2]octanium, and 1,1-dimethyl-4-methylpiperidinium are preferably used because of their excellent catalytic activity and industrial availability.

[0029] Incidentally, examples of the organic acid group or inorganic acid group constituting such a quaternary ammonium salt include organic acid groups such as formate group, acetate group, octylate group, oxalate group, malonate group, succinate group, glutarate group, adipate group, benzoate group, toluylate group, ethylbenzoate group, methyl carbonate group, phenol group, alkylbenzene sulfonic acid group, toluene sulfonic acid group, benzene sulfonic acid group, phosphate ester group, etc., and inorganic acid groups such as halogen group, hydroxyl group, hydrogen carbonate group, carbonate group, etc. Among these, the formate group, acetate group, octylate group, methyl carbonate group, halogen group, hydroxyl group, hydrogen carbonate group, carbonate group are preferred because of their excellent catalytic activity and industrial availability.

[0030] In addition, various catalysts composed of such quaternary ammonium salts are commercially available. For example, U-CAT18X, U-CAT2313 (manufactured by San Apro Ltd.), Kaolizer No.410, Kaolizer No.420 (manufactured by Kao Corporation), etc. can be mentioned.

[0031] In addition, as yet another additional essential component in the liquid A according to the present invention, a primary and / or secondary amino group-containing compound which is an amine compound having a primary and / or secondary amino group and an organic or inorganic acid are added and contained in a form in which they are combined, in other words, either separately or in the form of a reaction product obtained by reacting them in advance.

[0032] Here, the primary and / or secondary amino group-containing compound is not particularly limited as long as it is a compound having a primary and / or secondary amino group bonded and contained therein. For example, aliphatic amine compounds, aliphatic polyamine compounds, aromatic amine compounds, aromatic polyamine compounds, amino acids, alkanolamines, etc. can be mentioned. This primary and / or secondary amino group-containing compound reacts with the polyisocyanate at room temperature to promote crosslinking, and at the same time, foaming proceeds due to the reaction promotion by the tertiary amine, resulting in the formation of a good foam.

[0033] Specifically, examples of the aliphatic amine compound include linear amino group-containing compounds such as butylamine, octylamine, and dodecylamine, alicyclic amino group-containing compounds such as cyclohexylamine, and cyclic amino group-containing compounds such as piperidine. Examples of the aliphatic polyamine include linear amino group-containing compounds such as butanediamine, hexanediamine, octanediamine, polyetheramine, triethylenetetramine, tetraethylenepentamine, hydrazine, 1,2-diaminopropane, 1,3-diaminopropane, tetramethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, and diethylenetriamine, alicyclic amino group-containing compounds such as cyclohexanediamine, norbornenediamine, 4,4'-diaminocyclohexylmethane, isophoronediamine, and bisaminomethylcyclohexane, cyclic amino group-containing compounds such as piperazine, and aliphatic amino group-containing compounds having an aromatic ring such as xylylenediamine. Further, examples of the aromatic amine compound include amino group-containing compounds such as aniline, toluidine, anisidine, and methylaniline. Examples of the aromatic polyamine compound include amino group-containing compounds such as toluenediamine, methylenedianiline, phenylenediamine, diaminodiphenylmethane, diaminodiphenyl ether, trimethylphenylenediamine, diethyltoluenediamine, dimethylthiotoluenediamine, 4,4'-methylenebis(N-sec-butylaniline), aminobenzylamine, and methylenebis(ethylmethylaniline). Further, examples of the amino acid include compounds containing a carboxyl group and an amino group in the molecule such as lysine, valine, and asparagine. In addition, examples of the alkanolamine compound include compounds having an amino group and a hydroxyl group in the molecule such as ethanolamine, hexanolamine, and diethanolamine.In addition, polyoxyalkylene diamines obtained by converting the hydroxyl groups of polyoxyalkylene glycols obtained by addition polymerization of propylene oxide and / or ethylene oxide to water, ethylene glycol, propylene glycol, etc. into amino groups, and polyoxyalkylene triamines obtained by converting the hydroxyl groups of polyoxyalkylene triols obtained by addition polymerization of propylene oxide and / or ethylene oxide to glycerin, trimethylolpropane, etc. into amino groups can be mentioned. These amine compounds having primary and / or secondary amino groups can be used alone or in combination of two or more.

[0034] In the present invention, in order to effectively exhibit the function as a crosslinking agent, the primary and / or secondary amino group-containing compound as described above is preferably a polyamine compound having two or more primary and / or secondary amino groups in one molecule. In particular, in order to improve the properties such as reactivity and flame retardancy, it is preferably an amine compound having an aromatic ring (aromatic amine compound), more preferably an aromatic polyamine compound. Among them, an aromatic polyamine compound having a structure in which at least one of the positions adjacent to the amino group bonded to the aromatic ring is substituted with an alkyl group is particularly preferably used. Among these primary and / or secondary amino group-containing compounds, a compound containing a primary amino group is more preferably used.

[0035] In addition, in the present invention, among the primary and / or secondary amino group-containing compounds as described above, in order to exhibit better crosslinkability, a compound having a primary and / or secondary amino group content of 0.5 to 50 mmol / g, preferably 1 to 20 mmol / g, more preferably 3 to 15 mmol / g in the molecule is advantageously used. If the amount of the primary and / or secondary amino groups is less than 0.5 mmol / g, it may be difficult to sufficiently achieve the object of the present invention. On the other hand, if it exceeds 50 mmol / g, the crosslinking reaction may proceed too far, causing abnormal reactions, such as the chemical solution solidifying during the injection operation and an effective foam not being obtained.

[0036] Furthermore, such a primary and / or secondary amino group-containing compound is generally desirably contained in the A liquid so as to be in a ratio of 0.01 to 20 parts by mass, preferably 0.05 to 10 parts by mass, more preferably 0.1 to 5 parts by mass, with respect to 100 parts by mass of the polyisocyanate in the B liquid. If the content is less than 0.01 part by mass, the reaction between the amino group in the primary and / or secondary amino group-containing compound and the isocyanate group in the polyisocyanate in the B liquid becomes insufficient, resulting in insufficient strength of the solidified product or insufficient formation of the reaction product (foam) due to the insufficient progress of such a reaction. On the other hand, if the content exceeds 20 parts by mass, the crosslinking in the reaction product proceeds too far, causing abnormal reactions and solidification during the injection operation, and the formation of the desired foam may be prevented.

[0037] The organic or inorganic acids used in combination with the above-described primary and / or secondary amino group-containing compounds are organic acids such as sulfonic acids, carboxylic acids, phenols, and mineral acids (inorganic acids) such as hydrochloric acid, hydrofluoric acid, hydrobromic acid, hydroiodic acid, sulfuric acid, sulfamic acid, bisulfuric acid, phosphoric acid, boric acid, and nitric acid.

[0038] And as such an organic acid, examples of sulfonic acid include, specifically, methanesulfonic acid, benzenesulfonic acid, toluenesulfonic acid, alkylsulfonic acid, alkylbenzenesulfonic acid, etc. Examples of carboxylic acid include various carboxylic acids such as saturated, unsaturated, hydroxy, aromatic, etc. Generally, those having about 1 to 36 carbon atoms will be used.

[0039] More specifically, examples of carboxylic acid include straight-chain fatty acids such as formic acid, acetic acid, propionic acid, butyric acid, caproic acid, caprylic acid, capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, cerotic acid, montanic acid, melissic acid, etc.; unsaturated fatty acids such as undecylenic acid, palmitoleic acid, oleic acid, linoleic acid, linolenic acid, arachidonic acid, etc.; branched fatty acids such as isooctylic acid (2-ethylhexanoic acid), neotridecanoic acid, isomyristic acid, isopalmitic acid, isostearic acid, etc.; hydroxy fatty acids such as 12-hydroxystearic acid, ricinoleic acid, etc. Examples of polybasic acids include oxalic acid, malonic acid, succinic acid, cyclobutane-1,1-dicarboxylic acid, cyclohexane-1,2-dicarboxylic acid, phenylene-1,2-diacetic acid, diglycolic acid, dithioglycolic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecaneundioic acid, dodecanedioic acid, eicosanedioic acid, octacosanedioic acid, 1,10-decamethylenedioic acid, 1,12-dodecamethylenedioic acid, 1,15-pentadecamethylenedioic acid, 1,28-octacosamethylenedioic acid, 7-ethyloctadecanedioic acid, dimer acid, hydrogenated dimer acid, etc. Unsaturated dibasic acids such as fumaric acid, maleic acid, itaconic acid, etc., hydroxy polybasic acids such as tartaric acid, malic acid, mucic acid, citric acid, etc., amino acids, acylated amino acids, etc. can also be used.

[0040] In the present invention, such a primary and / or secondary amino group-containing compound and an organic or inorganic acid are separately added to and blended with the solution A. Preferably, they are pre-reacted and then added and contained in the form of a reaction product. Thus, when the organic or inorganic acid is added to and contained in the solution A, the reaction of the primary and / or secondary amino group-containing compound with the polyisocyanate can be effectively delayed at low temperatures, and the promotion of crosslinking and foaming can be simultaneously advanced, so that a good foam can be advantageously realized.

[0041] Here, the reaction between the primary and / or secondary amino group-containing compound and the organic or inorganic acid generally proceeds effectively by mixing them at room temperature and holding for about 1 to 10 minutes, whereby the desired reaction product can be obtained. At this time, stirring of the mixed solution is carried out as necessary. By pre-reacting the primary and / or secondary amino group-containing compound with the organic or inorganic acid and then adding it, the reaction of the organic or inorganic acid with the aqueous silicate solution can be advantageously suppressed or prevented. At this time, water or a solvent can be added to efficiently mix the primary and / or secondary amino group-containing compound and the organic or inorganic acid. The viscosity of the reaction product formed by their reaction is adjusted to be about 5 to 2000 mPa·s, more preferably 10 to 1000 mPa·s, at a temperature of 25°C.

[0042] When adding and blending such a primary and / or secondary amino group-containing compound and an organic or inorganic acid to the solution A, the blending ratio is appropriately selected. Preferably, the blending ratio (P) represented by the following formula is 0.3 to 2.5, preferably 0.4 to 2.2, more preferably 0.5 to 2.0, and still more preferably 0.6 to 1.2, and it is desirable to add and contain them at this ratio. P = [functional group amount of organic or inorganic acid per gram (mmol / g) × organic or inorganic [Amount of acid added to the machine (g)] / [(Functional group amount (mmol / g) of the primary and / or secondary amino group-containing compound per 1 g) × (Amount of the primary and / or secondary amino group-containing compound added ( g))]

[0043] In the above formula, the functional group amount of the acid per 1 g can be calculated by dividing the number of functional groups of the acid by the molar mass of the acid. Also, the amount of primary and / or secondary amino groups per 1 g can be calculated by dividing the number of amino groups of such an amino group-containing compound by the molar mass of the amino group-containing compound. And if such a mixing ratio (P) becomes too low compared to 0.3, it becomes difficult to fully exhibit the effect of using the organic or inorganic acid. On the other hand, if it becomes too high compared to 2.5, there is a risk of making it difficult to fully exhibit the cross-linking action by the primary and / or secondary amino group-containing compound.

[0044] By the way, in the liquid A according to the present invention, in addition to the amino group-containing compound and the predetermined acid as described above, various known active hydrogen group-containing compounds can be further contained as necessary. Among them, various known polyols that can react with the polyisocyanate component are preferably used.

[0045] And such polyols are not particularly limited, and those conventionally used as the polyol component in chemicals for ground injection or ground consolidation can be similarly used. For example, known polyether polyols, polyester polyols, etc. can be mentioned. These polyols can be used alone or can be used in combination as appropriate. Also, as the addition and blending amount of the polyol, an appropriate ratio is selected so as not to deviate from the gist of the present invention. Generally, it is 40 parts by mass or less, preferably 30 parts by mass or less, more preferably 20 parts by mass or less, with respect to 100 parts by mass of the aqueous silicate solution.

[0046] ​The polyether polyol described above is not particularly limited. For example, polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc., which have at least two or more active hydrogen groups; amines such as ethylenediamine; alkanolamines such as ethanolamine and diethanolamine, etc. can be used as starting materials, and those produced by the addition reaction of these with alkylene oxides such as ethylene oxide and propylene oxide can be used. Also, in the case of polyester polyol, it is not particularly limited. For example, polycarboxylic acid-based polyester polyols obtained by reacting polyhydric alcohols with polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, maleic acid, phthalic acid, terephthalic acid, trimellitic acid, dimer acid, etc., lactone-based polyester polyols obtained by ring-opening polymerization of lactones, castor oil-based polyester polyols, etc. can be mentioned.

[0047] On the one hand, as the polyisocyanate which is an essential constituent of the liquid B, one of the two liquids constituting the ground injection chemical composition targeted by the present invention, it is an organic isocyanate compound having two or more isocyanate groups (NCO groups) in the molecule. In the present invention, from the viewpoints of the strength and reaction rate of the reaction product (foam) obtained by the reaction with the above-mentioned liquid A, aromatic polyisocyanates are preferably used. Here, as the aromatic polyisocyanate, various known ones are appropriately selected and used. For example, diphenylmethane diisocyanate (MDI), polymethylene polyphenylene polyisocyanate (crude MDI), tolylene diisocyanate, polytolylene polyisocyanate, xylylene diisocyanate, naphthalene diisocyanate, etc. can be mentioned. Also, prepolymers, isocyanurate-modified products, carbodiimide-modified products, etc. of these aromatic polyisocyanates can be mentioned. These polyisocyanate components may be used alone or in combination of two or more. Generally, from the viewpoints of reactivity, economy, handleability, etc., MDI or crude MDI is preferably used. In addition, as the polyisocyanate in the liquid B, only such aromatic polyisocyanates are used. As long as the gist of the present invention is not deviated from, other known polyisocyanate components, for example, aliphatic polyisocyanates such as hexamethylene diisocyanate, alicyclic polyisocyanates such as isophorone diisocyanate, urethane prepolymers having isocyanate groups at the molecular terminals, isocyanurate-modified products and carbodiimide-modified products of these polyisocyanates, etc. can be used in combination, or further, these known polyisocyanate components can be used alone.

[0048] And such a polyisocyanate is generally contained in the liquid B at a ratio of 50 to 100% by mass, preferably 70 to 100% by mass, more preferably 80 to 100% by mass. When the content of this polyisocyanate is less than 50% by mass, there is a problem that the strength of the reaction product decreases. Therefore, it is desirable that the ratio of the polyisocyanate in the liquid B is higher, and furthermore, the liquid B can be composed only of such a polyisocyanate.

[0049] By the way, additives similar to those in the prior art can be added to the liquid A and the liquid B as described above, which constitute the chemical solution for ground injection according to the present invention, according to the purpose of use. For example, as additives for the liquid A, foaming agents, foam stabilizers, flame retardants, viscosity reducers, etc. can be mentioned. Such additives for the liquid A are used at a ratio of 0.1 to 30 parts by mass, preferably 0.5 to 20 parts by mass, per 100 parts by mass of the polyisocyanate. In addition, as additives for the liquid B, foam stabilizers, flame retardants, viscosity reducers, etc. can be mentioned. Among them, the foam stabilizer is used at a ratio of 0.05 to 5 parts by mass, preferably 0.1 to 3 parts by mass, per 100 parts by mass of the polyisocyanate, and the viscosity reducer is used at a ratio of 0.5 to 60 parts by mass, preferably 1 to 40 parts by mass, per 100 parts by mass of the polyisocyanate. Also, the flame retardant is used at a ratio of 1 to 50 parts by mass, preferably 5 to 40 parts by mass, per 100 parts by mass of the polyisocyanate.

[0050] Among these additives, as the foaming agent, known ones such as water, hydrocarbons, hydrofluorocarbons, hydrofluoroolefins, hydrochlorofluoroolefins, etc. can be used. This foaming agent is not particularly limited, but water is preferably used. This water is also supplied from the aqueous silicate solution constituting the liquid A, and reacts with the polyisocyanate in the liquid B to generate carbon dioxide gas, so it functions as a foaming agent.

[0051] In addition, 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 such foam stabilizers include silicone, nonionic surfactants, polyoxyalkylene-modified dimethylpolysiloxane, polysiloxane oxyalkylene copolymers, polyoxyethylene sorbitan fatty acid esters, castor oil ethylene oxide adducts, lauryl fatty acid ethylene oxide adducts, etc. 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 preferred, and polyoxyalkylene-modified dimethylpolysiloxane, polysiloxane oxyalkylene copolymers, etc. are preferred.

[0052] Furthermore, examples of the flame retardant include brominated flame retardants, chlorinated flame retardants, phosphorus-based flame retardants, halogenated phosphate esters, inorganic flame retardants, etc. These may be used alone or in combination of two or more. Among these, phosphate esters and halogenated phosphate esters are preferably used in terms of having less environmental impact and also functioning as a viscosity reducer for the foaming composition. Examples of the phosphate ester include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trixylenyl phosphate, etc. Examples of the halogenated phosphate ester include tris(chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(dichloropropyl) phosphate, tetrakis(2-chloroethyl) dichloroisopentyl diphosphate, polyoxyalkylene bis(dichloroalkyl) phosphate, etc.

[0053] In addition, the viscosity reducer is used as a solvent and is dissolved in Liquid A or Liquid B to reduce the viscosity of these liquids. As long as it has such a function, it is not particularly limited. For example, alcohols such as methanol and ethanol, ethers such as ethyl cellosolve and butyl cellosolve, cyclic esters such as propylene carbonate, esters such as dimethyl dicarboxylate and ethylene glycol monomethyl ether acetate, petroleum-based hydrocarbons, and the like can be mentioned. These may be used alone or in combination of two or more.

[0054] By the way, Liquid A and Liquid B prepared according to the present invention are each adjusted so that the viscosity at a temperature of 25°C is 400 mPa·s or less, preferably 5 to 300 mPa·s, more preferably 10 to 200 mPa·s. When this viscosity becomes higher than 400 mPa·s, problems such as an increase in pressure loss when injecting into the natural ground and difficulty in the injection operation will be caused. In addition, if such a viscosity becomes too low, it will be easily diluted with water, and problems such as white turbidity of the drainage will be easily caused.

[0055] Further, when using the chemical liquid composition for ground injection according to the present invention composed of such Liquid A and Liquid B, the two liquids are mixed at the time of use and injected into the target ground, rock mass, etc. according to a known method, and are reaction-cured to form a high-strength solidified body. The mixing ratio (A:B) of Liquid A and Liquid B will be appropriately changed depending on the content of active oxygen groups in Liquid A and the content of NCO groups in Liquid B. Generally, on a mass basis, A:B = 2:1 to 1:3, preferably in the range of 1:1 to 1:2, and will be adopted. Also, regarding the use method of Liquid A and Liquid B, as long as the two liquids can be surely mixed immediately before their use, there is no particular limitation, and various conventionally known injection methods will be appropriately adopted.

[0056] When the liquid A and the liquid B are mixed, in the chemical liquid composition according to the present invention, at 20°C, a cured reaction product (foam) is formed such that the foaming magnification is generally 20 times or less, preferably 3 to 15 times. Note that if the foaming magnification is too high, there is a risk of causing problems such as a decrease in the properties such as the compressive strength of the generated foam.

[0057] Furthermore, when the liquid A and the liquid B are mixed and foamed, the reaction time, in other words, the rise time, is preferably within 300 seconds, and the lower limit is about 20 seconds. If this rise time is longer than 300 seconds, after injection into the ground, until it solidifies, problems such as the chemical liquid flowing out into the flowing water and causing turbidity and foaming of the water will occur. Note that if the rise time is too short, for example, shorter than 20 seconds, problems such as the reaction progressing too far and blocking the injection pipe of the chemical liquid, or it becoming difficult to sufficiently penetrate into the ground will be caused, so attention is required.

Examples

[0058] Hereinafter, several examples and comparative examples of the present invention will be shown to further specifically clarify the present invention. Needless to say, the present invention is not restricted by the description of such examples. Also, it should be understood that in addition to the following examples, and further, in addition to the above specific descriptions, various changes, modifications, improvements, etc. can be made based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

[0059] Note that regarding the properties (viscosity) of the liquid A and the liquid B obtained in the following examples and comparative examples, as well as the foaming magnification, rise time, foaming magnification ratio, and compressive strength of the reaction product when the liquid A and the liquid B are mixed and reaction-cured, they were measured or evaluated according to the following methods respectively. Also, “%” and “parts” shown below are both indicated on a mass basis.

[0060] (1) Viscosity The viscosities of the Liquid A and Liquid B obtained in the examples and comparative examples were measured using a B-type viscometer in accordance with JIS-K-7117-1, respectively.

[0061] (2) Foaming ratio and rise time (reaction time) After adjusting the various Liquid A and Liquid B shown in the following table to a liquid temperature of 20°C (room temperature) or 10°C (low temperature), respectively, 100 ml in total was weighed into a 1 L cup at the mixing ratio shown below and stirred at 400 rpm for 10 seconds using hand mixing. Then, the time from the start of the stirring until the foaming height became the highest was defined as the rise time (reaction time). Also, the foaming height of the reaction product after the completion of such a curing reaction was measured visually to determine the foaming ratio. Furthermore, the ratio of the foaming ratio at 10°C to the foaming ratio at 20°C thus obtained was calculated. Note that the closer the 10°C / 20°C foaming ratio is to 1.0, the more stable the foam can be obtained with respect to temperature changes.

[0062] (3) Compressive strength The Liquid A and Liquid B adjusted to a temperature of 10°C were weighed and mixed at the mixing ratio shown in the following table so that the total amount was 100 ml. Then, immediately after such mixing, a predetermined amount of the mixture of Liquid A and Liquid B was put into a bottomed cylindrical mold with an inner diameter of 50 mm and a height of 100 mm so that the foaming ratio was three times the volume, covered, and cured for 2 hours or more. Thereafter, the demolded reaction product was cured at 10°C for 24 hours or more, and the compressive strength was measured in accordance with JIS-K-7220:2006.

[0063] First, the following various raw materials were prepared as the constituent components of Liquid A or Liquid B used in the following examples and comparative examples. Aqueous silicate solution : Sodium silicate No. 1 (product of Fuji Chemical Co., Ltd., molar ratio: 2.1, solid content: adjusted to about 40% by adding water to 48%) : Sodium silicate No. 2 (product of Fuji Chemical Co., Ltd., molar ratio: 2.5, solid content: 40%) Tertiary amine catalyst : Caurizer No. 26 (product of Kao Corporation, N,N-dimethylaminoethoxyethanol, MW: 133.2) : Caurizer No. 1 (product of Kao Corporation, N,N,N’,N’-tetramethylhexamethylenediamine, MW: 172.3) Primary / secondary amino group-containing compound : Polyetheramine T403 (polyetheramine, product of BASF, molecular weight: 400, functional group: NH2×3) : Ethacure 100 (diethyltoluenediamine, product of Albemarle, molecular weight: 178, functional group: NH2×2) : Ethacure 420 [4,4’-methylenebis(N-sec-butylaniline), product of Albemarle, molecular weight: 310, functional group: NH×2] : n-octylamine [product of Tokyo Chemical Industry Co., Ltd., molecular weight 129.3, functional group: NH2×1] Organic or inorganic acid : Acetic acid (MW: 60, functional group: 1) : Linoleic acid (MW: 280.5, functional group: 1) : Citric acid (MW: 210, functional group: 3) : 36% hydrochloric acid Polyol : PG (propylene glycol, product of Tokyo Chemical Industry Co., Ltd.) : PP400 (product of Sanyo Chemical Industries, Ltd., Sunnex PP400, polyether polyol, molecular weight: 400, number of functional groups: 2) : PP1000 (product of Sanyo Chemical Industries, Ltd., Sunnex PP1000, polyether polyol, molecular weight: 1000, number of functional groups: 2) : EDP1100 (product of ADEKA Corporation, Adeka Polyol EDP1100, polyether polyol, molecular weight: 1100, number of functional groups: 4) Polyisocyanate : Lupranate M11S (product of BASF INOAC Polyurethane Co., Ltd., polymeric MDI) : Prepolymer (obtained by adding 5 parts of the above-mentioned PP1000 to 100 parts of Lupranate M11S and reacting at a temperature of 70°C for 3 hours) : Takenate D-170N (product of Mitsui Chemicals, Inc., isocyanurate form of hexamethylenediamine diisocyanate) Foaming agent : L-6970 (product of Momentive Performance Materials Japan G.K., silicone-based foaming agent)

[0064] (Examples 1 to 20) -Preparation of Liquid A- The various raw materials prepared above, namely, the aqueous silicate solution, the tertiary amine catalyst, the primary / secondary amino group-containing compound, the acid, and the polyol, were uniformly mixed in the various combinations and blending ratios shown in Tables 1 to 4 below, respectively, to prepare the various Liquid A blending compositions according to Examples 1 to 20. In Examples 1 to 9 and 11 to 20, the primary / secondary amino group-containing compound and the acid shown in Tables 1 to 4 below were premixed at room temperature and stirred for 5 minutes to react, and the reaction product obtained was used for mixing, while in Example 10, the primary / secondary amino group-containing compound and the acid shown in Table 2 below were added and blended separately without pre-reacting. Then, the viscosity of the obtained Liquid A blending composition at 25°C was measured, and the results are shown in Tables 1 to 4 below.

[0065] -Preparation of Liquid B- The raw materials of Liquid B prepared above, namely, the polyisocyanate and the foaming agent, were uniformly mixed in the various combinations and blending ratios shown in Tables 1 to 4 below, respectively, to prepare the various Liquid B blending compositions according to Examples 1 to 20. Then, the viscosity of the obtained Liquid B blending composition at 25°C was measured, and the results are shown in Tables 1 to 4 below.

[0066] -Reaction of Liquid A and Liquid B- The liquid A and liquid B obtained above were uniformly mixed at room temperature (20 °C) or low temperature (10 °C) at the mixing ratios shown in Tables 1 to 4, and after reacting them, various evaluation tests were conducted according to the above-described evaluation method, and the results are shown in Tables 1 to 4 below.

[0067] (Comparative Example 1) In Example 1, tests were conducted in the same manner as in Example 1, except that only the primary / secondary amino group-containing compound was added instead of the form of the reaction product with an acid. And the results obtained are shown in Table 5 below.

[0068] (Comparative Example 2) In Example 2, tests were conducted in the same manner as in Example 2, except that only an acid was added without adding the primary / secondary amino group-containing compound. And the results obtained are shown in Table 5 below.

[0069] (Comparative Example 3) In Example 18, tests were conducted in the same manner as in Example 1, except that an acid was not added in addition to the addition of only the primary / secondary amino group-containing compound. And the results obtained are shown in Table 5 below.

[0070] (Comparative Example 4) In Example 18, tests were conducted in the same manner as in Example 2, except that the primary / secondary amino group-containing compound was not added in addition to the addition of only an acid, and the results obtained are shown in Table 5 below.

[0071]

Table 1

[0072]

Table 2

[0073]

Table 3

[0074]

Table 4

[0075]

Table 5

[0076] As is clear from the results of Tables 1 to 4 above, in the chemical liquid compositions comprising Liquid A and Liquid B according to the present invention in Examples 1 to 20, all of them have a reaction time of 300 seconds or less, are excellent in reaction activity, and can form a cured product (foam) having a high compression strength at a foaming magnification of about 3 times or more. Moreover, they are excellent in reaction time and foaming magnification during low-temperature foaming at 10°C, and as a result, the 10°C / 20°C foaming magnification ratio is 0.50 to 0.88, indicating that a foam stable against temperature changes can be formed.

[0077] On the other hand, as shown in Table 5, in the chemical liquid compositions comprising Liquid A and Liquid B prepared in Comparative Examples 1 to 4, a cured product (foam) having a foaming magnification of 3 times or more could not be obtained, and therefore, the compression strength could not be measured. Moreover, since the foaming magnification of the cured product (foam) obtained by low-temperature foaming was low, the 10°C / 20°C foaming magnification ratio was significantly low, and it became clear that it was difficult to expect the formation of a foam stable against temperature changes. In Comparative Examples 2 and 4, only an acid was added, and since a primary / secondary amino group-containing compound was not added or blended, gelation of Liquid A was induced, and therefore, the reaction between Liquid A and Liquid B did not proceed sufficiently, and the desired cured product (foam) could not be obtained.

Claims

1. In a chemical solution composition for ground injection, which comprises liquid A containing an aqueous silicate solution and a tertiary amine catalyst as essential components, and liquid B containing a polyisocyanate as an essential component, the liquid A further contains a primary and / or secondary amino group-containing compound and an organic or inorganic acid, individually or in the form of a reaction product thereof, and is characterized in that it is added and contained. A chemical solution composition for ground injection.

2. The chemical solution composition for ground injection according to claim 1, wherein the primary and / or secondary amino group-containing compound is a polyamine compound having two or more primary and / or secondary amino groups in one molecule.

3. The chemical solution composition for ground injection according to claim 1 or claim 2, wherein the primary and / or secondary amino group-containing compound is an aromatic amine compound.

4. The chemical solution composition for ground injection according to any one of claims 1 to 3, wherein the primary and / or secondary amino group-containing compound is added and contained in a proportion of 0.01 to 20 parts by mass with respect to 100 parts by mass of the polyisocyanate.

5. The chemical solution composition for ground injection according to any one of claims 1 to 4, wherein the primary and / or secondary amino group-containing compound and the organic or inorganic acid are added and contained in a proportion such that the mixing ratio (P) represented by the following formula is 0.3 to 2.

5. P = [functional group amount of organic or inorganic acid per gram × amount of organic or inorganic acid added] / [functional group amount of primary and / or secondary amino group-containing compound per gram × amount of primary and / or secondary amino group-containing compound added]

6. The chemical solution composition for ground injection according to any one of claims 1 to 5, wherein the tertiary amine catalyst has an alcoholic hydroxyl group.

7. The chemical solution composition for ground injection according to any one of claims 1 to 6, wherein the liquid A further contains a polyol.

8. The chemical solution composition for ground injection according to any one of claims 1 to 7, wherein the liquid A and the liquid B each have a viscosity of 400 mPa·s or less at a temperature of 25°C.

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