JP5826149B2 - Method for producing liquid composition containing tetrahydro-4H-1,3,5-oxadiazin-4-one - Google Patents

Description

  The present invention relates to a method for producing a liquid composition containing tetrahydro-4H-1,3,5-oxadiazin-4-one.

  Various compounds are produced by reacting urea and formaldehyde in water.

  For example, Patent Document 1 discloses that, as a fertilizer composition, certain reaction products of urea and formaldehyde exhibit remarkable properties in the on-leaf nutrient supply of growing plants. As the production conditions, an aqueous mixture of urea and formaldehyde having a urea: formaldehyde molar ratio of about 1: 1 or more and about 2: 1 or less is prepared. And heating the mixture at a temperature between about 75 ° C. and boiling point, while the pH of the mixture is strong until at least about 90% of the formaldehyde is in bound form and at least about 60% is in the form of a methylol compound. It is disclosed to maintain at about 8.5 to 10 with alkali and then continue the heating at pH 7 to 8.5 until at least 50% but not more than about 80% of the formaldehyde is in the methylene form. The reaction product is a concentrated aqueous solution containing about 80% to 90% by weight of urea and formaldehyde partial reactants, is transparent at room temperature for at least about 30 days, and “salting out” at 0 ° C. for at least 7 days. That is, it is described that no solid is precipitated.

  In addition, Patent Document 2 discloses that when used as a wet chemical for paper, urea-formaldehyde, which causes formaldehyde emission slightly when compared with conventionally used condensates based on urea and formaldehyde when paper is dried. Condensates are disclosed. Then, a) urea and triethanolamine are reacted in a molar ratio of 1 to 6: 1 at a temperature of 130 to 180 ° C. under decomposition of ammonia, and b) a reaction product obtained in step (a). Is methylolated with formaldehyde in an aqueous medium in the basic pH range.

  Moreover, in manufacture of a melamine-urea resin, patent document 3 makes it a subject that there is much formaldehyde released from the obtained resin, 1.0 mol of melamine, 4.0-4.5 mol of urea, and formaldehyde 5. 2-dimethyl or 2-diethylaminoethanol is produced by adding 2-dimethyl or 2-diethylaminoethanol to a mixture at a ratio of 5 to 7.5 mol to make the mixture alkaline and maintaining at 75 ° C. to reflux. Is added to keep the pH of the reaction solution from dropping below 7.5.

  Patent Document 4 describes a hydraulic cement mixture containing an additive containing a water-soluble hydroxylated adduct with a monomer formed by the reaction of an aldehyde and urea. In Example 1, Among such adducts, it is described that monomethylol urea obtained by condensing 1 mol of formaldehyde with 1 mol of urea was prepared by dissolving 50 g of paraformaldehyde in 1 L of water, adding 1 g of triethanolamine and 100 g of urea, and allowing to stand for 4 days. ing.

JP-A-55-71689 JP-T-4-503824 JP 59-108019 A JP 48-36223 A

  In Patent Documents 1 and 2, the reaction between urea and formaldehyde is carried out, but the purpose is to produce a resin. The resulting condensate is a monomer in which 1 to 2 moles of formaldehyde are condensed to 1 mole of urea. In addition, a multimer containing 2 mol or more of urea is produced. However, in order to use a compound obtained by methylating urea with formaldehyde in applications other than resins, for example, additives such as chelating agents, to increase the number of molecules per unit mass and increase the chelating power per molecule It is desirable to increase the monomer content as much as possible to reduce the multimer content. From such an aspect, when urea is methylolated with formaldehyde, a production method with a high yield of a monomer in which 2 moles of formaldehyde are condensed with 1 mole of urea is desired. Among them, tetrahydro-4H-1,3,5-oxadiazin-4-one, which is a compound in which dimethylolurea in which 2 mol of formaldehyde is condensed with 1 mol of urea is ring-closed, is an intermediate of useful compounds such as pharmaceuticals and agricultural chemicals. It is a compound that is expected to be used as a chelating agent, and a method for obtaining it in a high yield is desired.

  Further, when urea is methylolated with formaldehyde, the aqueous solution of the reaction product obtained immediately after the methylolation reaction may be stored at room temperature to cause turbidity or precipitation of the aqueous solution. Although the reaction product of Patent Document 1 is excellent in storage stability, it is considered that a large amount of urea is contained in the reaction product, and the methylol group in the product is capped with urea. Compounds with capped methylol groups are not suitable for chelating agents. Patent Document 4 does not describe that tetrahydro-4H-1,3,5-oxadiazin-4-one is produced with high yield and the stability of an aqueous solution is improved.

  An object of the present invention is to provide a production method capable of producing a liquid composition having a high yield of tetrahydro-4H-1,3,5-oxadiazin-4-one and having excellent storage stability. is there.

The present invention comprises a compound 3 represented by the following formula (3) and water, wherein the compound 1 represented by the following formula (1) and the compound 2 represented by the following formula (2) are reacted in water. A method for producing a liquid composition having a pH of 10.0 or more,
The charged molar ratio of Compound 2 and Compound 1, Compound 2 / Compound 1 is 0.3 or more and 1.7 or less,
The reaction between Compound 1 and Compound 2 is carried out at 15 ° C. or higher and 50 ° C. or lower and in the presence of alkyldiethanolamine at pH 10.0 or higher.
The present invention relates to a method for producing a liquid composition.

  According to the present invention, a liquid composition having a high yield of tetrahydro-4H-1,3,5-oxadiazin-4-one [compound 3 represented by formula (3)] and excellent storage stability of the compound. The manufacturing method which can be manufactured as is provided.

  The reason why the production method of the present invention exhibits the effect is not clear, but is estimated as follows. It is known that the reaction of urea and formaldehyde in an aqueous solution has two main reactions, a methyleneation reaction and a methylolation reaction. These reactions are dominated by a methyleneation reaction mainly composed of a high molecular weight urea-formaldehyde condensate in an acidic aqueous solution, and a low molecular weight urea-formaldehyde condensate containing a monomer in an alkaline aqueous solution. The methylolation reaction as the main component is dominant. In the present invention, the presence of alkyldiethanolamine suppresses fluctuations in pH due to side reactions such as formaldehyde cannizzaro reaction and ammonia generation due to alkaline decomposition of urea, and the pH is set to 15 ° C. or higher and 50 ° C. or lower to 10.0 or higher. Therefore, it is presumed that a methylolation reaction can be preferentially advanced, and as a result, a liquid composition having a high content of compound 3 and a low content of multimers can be obtained. In addition, since the multimer has a large number of reaction points, it easily undergoes a cross-linking reaction with other multimers, and the multimer undergoes a cross-linking reaction during storage, resulting in a high molecular weight and an insoluble white precipitate. In the present invention, a liquid composition having a low content of multimers and a high content of compound 3, which is a cyclic compound having low reactivity, is obtained. Since compound 3 can be stably present in an aqueous solution having a pH of 10 or more, storage stability is obtained. It is considered that the property is excellent.

  The production method of the present invention comprises reacting compound 1 represented by formula (1) and compound 2 represented by formula (2) in water, and containing compound 3 represented by formula (3) and water. A liquid composition is obtained. By the reaction of compound 1 and compound 2, a condensate of compound 1 and compound 2 is obtained. One of the condensates is compound 3. Compound 1 represented by formula (1) is urea. Compound 2 represented by formula (2) is formaldehyde. Compound 3 represented by the formula (3) is tetrahydro-4H-1,3,5-oxadiazin-4-one. The reaction of Compound 1 and Compound 2 is carried out using water as a solvent, and the reaction raw material can be used as an aqueous solution.

  The charged molar ratio of Compound 2 and Compound 1 in the production method of the present invention is 0.3 to 1.7 in terms of Compound 2 / Compound 1, from the viewpoint of improving the yield of the condensate of Compound 2 and Compound 1. 0.5 or more is preferable, 0.75 or more is more preferable, 1.5 or less is preferable, and 1.25 or less is more preferable.

  From the viewpoint of improving the yield of the condensate of compound 2 and compound 1, the total amount of charged amounts of compound 1 and compound 2 is 100 parts by mass of the total amount of raw materials (compound 1, compound 2, alkyldiethanolamine, water). On the other hand, 3.0 mass parts or more are preferable, 6.0 mass parts or more are more preferable, and 11 mass parts or more are still more preferable. Moreover, from a soluble viewpoint of the compound 3 in water, 25 mass parts or less are preferable, 20 mass parts or less are more preferable, and 14 mass parts or less are still more preferable.

  From the viewpoint of improving the yield of the condensate of compound 2 and compound 1, the amount of compound 1 charged is 1.0 with respect to 100 parts by mass of the total amount of raw materials (compound 1, compound 2, alkyldiethanolamine, water). More than mass parts are preferable, 5.0 mass parts or more are more preferable, and 8.0 mass parts or more are still more preferable. Moreover, from a soluble viewpoint of the compound 3 in water, 20 mass parts or less are preferable, 12 mass parts or less are more preferable, and 9.0 mass parts or less are still more preferable.

  From the viewpoint of improving the yield of the condensate of compound 2 and compound 1, the amount of compound 2 charged is 0.5 with respect to 100 parts by mass of the total amount of raw materials (compound 1, compound 2, alkyldiethanolamine, water). More than mass part is preferable, 1.0 mass part or more is more preferable, and 3.0 mass part or more is still more preferable. Moreover, from a soluble viewpoint of the compound 3 in water, 10 mass parts or less are preferable, 8.0 mass parts or less are more preferable, and 5.0 mass parts or less are still more preferable.

  From the viewpoint of the solubility of compound 3 in water, the amount of water charged is preferably 70 parts by mass or more, and 75 parts by mass or more with respect to 100 parts by mass of the raw materials (compound 1, compound 2, alkyldiethanolamine, water). More preferred is 80 parts by mass or more. Moreover, from a viewpoint of improving the yield of the compound 3, 95 mass parts or less are preferable, 90 mass parts or less are more preferable, and 88 mass parts or less are still more preferable. When raw materials other than water are used as an aqueous solution, the amount of water taken into the reaction system by the aqueous solution is also included in the amount of water as the reaction solvent.

  In the present invention, compound 1 and compound 2 are reacted in the presence of alkyldiethanolamine. Due to the pH buffering action of alkyldiethanolamine, the pH of the liquid composition can be maintained at 10.0 or more during reaction or storage. Among the alkyldiethanolamines, alkyldiethanolamine having an alkyl group having 1 to 3 carbon atoms is preferable from the viewpoint of suppressing a decrease in pH during the reaction, and alkyldiethanolamine having an alkyl group having 1 carbon atom, that is, N-methyldiethanolamine is more preferable. preferable. Alkanolamines that do not have an alkyl group, such as triethanolamine, diethanolamine, and monoethanolamine, are low in pH-increasing action and low in pH buffering ability, resulting in large pH reduction during the reaction. The effect of improving the yield of compound 3 and the effect of improving the storage stability of the resulting aqueous solution cannot be obtained.

  From the viewpoint of improving the yield of compound 3, the amount of alkyldiethanolamine charged is preferably 0.1 parts by mass or more with respect to 100 parts by mass of the total amount of raw materials (compound 1, compound 2, alkyldiethanolamine, water), 0.3 mass part or more is more preferable, and 0.5 mass part or more is still more preferable. Moreover, from the viewpoint of economy, 5.0 parts by mass or less is preferable, 1.0 parts by mass or less is more preferable, and 0.6 parts by mass or less is still more preferable because of saturation of pH buffering action.

  The charged molar ratio of alkyldiethanolamine and the total of compound 1 and compound 2 [alkyldiethanolamine / (total of compound 1 and compound 2)] is preferably 0.005 or more from the viewpoint of improving the yield of compound 3. 0.010 or more is more preferable, 0.013 or more is still more preferable, 0.100 or less is preferable, 0.050 or less is more preferable, 0.025 or less is still more preferable, and 0.018 or less is still more preferable.

  The reaction temperature in the production method of the present invention is 15 ° C. or higher and 50 ° C. or lower. From the viewpoint of improving the reaction rate, 20 ° C or higher is preferable, 35 ° C or higher is more preferable, and 38 ° C or higher is even more preferable. Moreover, from a viewpoint of improving the yield of the compound 3, 45 degrees C or less is preferable and 42 degrees C or less is more preferable.

  The reaction pH in the production method of the present invention is a pH from the start of the reaction to the end of the reaction. In the reaction of Compound 1 and Compound 2, the pH tends to decrease as the reaction proceeds. In the production method of the present invention, when no pH adjuster or the like is added during the reaction, the pH at the start of the reaction and the pH at the end of the reaction may be within the range of the present invention. When adding a pH adjuster or the like during the reaction, both the pH before and after the addition of the pH adjuster are within the scope of the present invention in addition to the pH at the start of the reaction and the pH at the end of the reaction. That's fine. The reaction pH in the production method of the present invention is 10.0 or more from the viewpoint of suppression of the crosslinking reaction due to ring-opening of compound 3 and suppression of decrease in storage stability of the liquid composition. From the viewpoint of improving compoundability when using the liquid composition obtained in the present invention, the pH is preferably 13.0 or less, more preferably 12.0 or less, and even more preferably 11.5 or less. The reaction pH is the pH of the reaction system, and may be the pH of a mixture containing water, compound 1, compound 2, and alkyldiethanolamine. In addition, in the reaction of Compound 1 and Compound 2 that are targets of the production method of the present invention, the pH tends to decrease as the reaction proceeds. Therefore, in the present invention, the pH at the start of the reaction is 10.5 or more. It is preferably 11.0 or more, more preferably 13.0 or less, more preferably 12.5 or less, even more preferably 12.0 or less, and more preferably 11.5 or less. Further preferred. The pH after completion of the reaction is 10.0 or more, and is preferably 10.5 or more, more preferably 11.0 or more, from the viewpoint of storage stability of the liquid composition. By carrying out the reaction at a predetermined pH and temperature of the present invention in the presence of alkyldiethanolamine, a liquid composition having a pH of 10.0 or more of the liquid composition is usually obtained in the production method of the present invention. A pH adjuster such as an acid or an alkali can be added to the composition. In the present invention, the pH may be controlled with a pH adjusting agent so that the pH becomes 10.0 or more until the end of the reaction.

  The reaction time in the production method of the present invention is preferably 1.5 hours or longer and more preferably 2 hours or longer from the viewpoint of improving the yield of the condensate of Compound 2 and Compound 1. Further, from the viewpoint of improving the yield of compound 3, the reaction time is preferably 4.5 hours or less, and more preferably 3 hours or less.

  In the present invention, the time when Compound 1 and Compound 2 first contact each other is regarded as the reaction start time, and the amount of decrease in Compound 2 over 30 minutes is relative to the total of the raw materials (Compound 1, Compound 2, alkyldiethanolamine, water). It is preferable to set the time when the reaction is 0.3% by mass or less as the end of the reaction. This means that the point in time when the reaction is completed can be determined when the compound 2 is hardly consumed and the reaction is not substantially progressing. The quantification of compound 2 in the sample can be determined by reacting the sample with hydroxylamine hydrochloride and titrating with sodium hydroxide. In the present invention, the reaction operation may be terminated immediately at the end of the reaction, but the reaction operation can be continued.

  Furthermore, the compound 2 is not exposed to the alkaline solution until the reaction starts, the cannizzaro reaction is suppressed, the yield of the condensate of the compound 2 and the compound 1 is improved, and the rapid reaction that the multimer is generated is further suppressed. From the viewpoint of improving the content of the compound 1, a method of adding the compound 2 to the mixture containing the compound 1, the alkyldiethanolamine and water, for example, the compound 1, the alkyldiethanolamine and water are put in a reaction vessel, and the mixture is heated at a predetermined temperature, A method in which an aqueous solution (formalin) containing Compound 2 is added dropwise with stirring after the predetermined pH is obtained is preferable. After completion of the addition of compound 2, it is preferable to continue the stirring while aging while maintaining the reaction temperature. When the aqueous solution of Compound 2 is added dropwise, the time required for the addition is preferably 1 hour or more, more preferably 1 and a half hours or more from the viewpoint of improving the content of Compound 3 due to the uniformity of the reaction, and the side reaction From the viewpoint of suppressing the above, the time required for dropping is preferably 3 hours or less, and more preferably 2 hours or less. The aging time is preferably 0.5 hours or more from the viewpoint of completion of the reaction and the uniformity of the product, more preferably 1 hour or more, and preferably 3 hours or less from the viewpoint of suppressing the side reaction, 2 hours or less is more preferable. The total time of dripping and aging is preferably 1.5 hours or more, more preferably 2 hours or more, from the viewpoint of improvement of the content of compound 3, completion of the reaction, and product uniformity, From the viewpoint of suppression, 4.5 hours or less is preferable, and 3 hours or less is more preferable.

  In the present invention, a polar solvent (methanol, ethanol, etc.) can be used in combination with the reaction solvent in addition to water as long as the effects of the present invention are not impaired. The reaction pressure is not particularly limited, and the reaction can be performed under pressure or reduced pressure if necessary. Any of a batch system, a semi-batch system, a continuous system, etc. can be adopted as the reaction system. In addition, an additive such as an antifoaming agent can be used as a raw material within a range not impairing the effects of the present invention. In the reaction solvent, the proportion of water is preferably 50% by mass or more, more preferably 70% by mass or more, further 90% by mass or more, and further 100% by mass from the viewpoint of the volatility of the solvent during the reaction and the temperature control.

  In the production method of the present invention, an aqueous solution containing Compound 1, Compound 2 and water is prepared in a reaction vessel, and the addition amount is adjusted by adding alkyldiethanolamine to a pH of 10.0 or more, and the temperature is 15 ° C. It can also carry out by the method of making it react at 50 degrees C or less and stirring.

  In the production method of the present invention, in the obtained liquid composition, the content of compound 3 is preferably 1.4% by mass or more, more preferably 2.0% by mass or more, from the viewpoint of improving storage stability. More preferably 2.5% by mass or more, more preferably 3.2% by mass or more, more preferably 30% by mass or less, more preferably 15% by mass or less, still more preferably 10% by mass or less, and 8.0% by mass. % Or less is even more preferable.

  In the production method of the present invention, a liquid composition having a high content of the compound 3 represented by the formula (3) in the solid content is obtained. The amount of the solid content in the liquid composition is preferably 5 parts by mass or more and more preferably 10 parts by mass or more with respect to 100 parts by mass of the liquid composition from the viewpoint of improving the compoundability when using the liquid composition. Preferably, 12 parts by mass or more is more preferable, and from the viewpoint of improving storage stability, 30 parts by mass or less is preferable, 25 parts by mass or less is more preferable, and 20 parts by mass or less is more preferable. The content of water in the liquid composition is preferably 70 parts by mass or more, more preferably 75 parts by mass or more, and 80 parts by mass or more with respect to 100 parts by mass of the liquid composition from the viewpoint of improving storage stability. Furthermore, 95 mass parts or less are preferable, 90 mass parts or less are more preferable, and 88 mass parts or less are still more preferable. The content of Compound 3 in the liquid composition is preferably 25% by mass or more, more preferably 35% by mass or more, still more preferably 40% by mass or more, and 45% by mass in the condensate obtained from Compound 1 and Compound 2. % Or more is still more preferable, 50 mass% or more is further more preferable, and 55 mass% or more is still more preferable. The content of Compound 3 in the condensate is 100% by mass or less, preferably 75% by mass or less, more preferably 60% by mass or less from the viewpoint of ease of production from Compound 1 and Compound 2.

  The present invention is a process for producing Compound 3 in which Compound 1 and Compound 2 are reacted in water in the presence of alkyldiethanolamine, wherein the charged molar ratio of Compound 1 and Compound 2 is 0.3 for Compound 2 / Compound 1. The production method is 1.7 or less, the reaction pH is 10.0 or more, and the reaction temperature is 15 ° C. or more and 50 ° C. or less. In the production method of the present invention, since the pH is 10.0 or more until the end of the reaction, a liquid reaction product having a pH of 10.0 or more containing Compound 3 and water is obtained.

  The liquid composition obtained by the production method of the present invention has a high content of compound 3 represented by formula (3). Compound 3 is ring-opened to become a compound having two hydroxyl groups, that is, 1,3- (hydroxymethyl) urea (sometimes referred to as N, N'-dimethylolurea). This compound can be used as a chelating agent blended in a cleaning agent or the like, for example, a chelating agent for a steel plate cleaning agent. Since the liquid composition containing the compound 3 is a liquid composition containing 1,3- (hydroxymethyl) urea in an equilibrium state, the liquid composition obtained by the production method of the present invention is used for a steel plate cleaner and a plant fertilizer. It can be used for compositions, papermaking additives, fiber finishes, water resistance agents, hydraulic composition additives, paint / ink raw materials, organic synthetic raw materials, resin raw materials, and the like.

  For example, since the liquid composition containing the compound 3 is a liquid composition containing 1,3- (hydroxymethyl) urea in an equilibrium state, it can be used as it is as a chelating agent for a steel sheet cleaner. Examples of such a steel plate cleaning agent include a cleaning agent containing an alkali agent, a surfactant, and water. Examples of the alkali agent include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. Examples of the surfactant include a nonionic surfactant obtained by adding an alkylene oxide to an alcohol having 8 to 22 carbon atoms. Moreover, as other components mix | blended with an iron and steel cleaning agent, dispersing agents, such as an antifoamer and polyacrylic acid, a thickener, etc. are mentioned. From the viewpoint of detergency of oil such as rolling oil attached to the steel sheet, the liquid composition obtained according to the present invention has an amount of compound 3 of 0.01% by mass or more, and further 0.1 mass in the steel sheet detergent. % Or more, and preferably 10% by mass or less, and more preferably 5.0% by mass or less. In addition, from the viewpoint of cleaning properties of oil such as rolling oil attached to the steel sheet, the steel detergent preferably has a pH of 20 or higher, preferably 13 or higher, and more preferably 14 or higher.

  The process targeted by the steel sheet cleaning agent using the liquid composition obtained by the production method of the present invention is a cleaning process, and includes continuous cleaning, that is, immersion cleaning, spray cleaning, brush cleaning, electrolytic cleaning, and the like. Oil stains such as rolling oil and solid stains such as iron powder can be washed away. The steel sheet cleaning agent can be used for dipping and electrolytic cleaning in the cleaning process, and can be suitably applied when the rolled steel sheet is passed through an alkali immersion cleaning tank and an alkaline electrolytic cleaning tank.

Examples and Comparative Examples <Production of Composition A>
450 g (7.50 mol) of urea (Compound 1) and 3588 g of distilled water were added to a 10 L three-necked flask and mixed at 200 rpm for 10 minutes using a stirring blade (three blades, diameter 70 mm). Thereafter, 27.0 g (0.23 mol) of N-methyldiethanolamine was added to adjust the pH to 11.3, and then the temperature was raised to 40 ° C. Subsequently, 305 g of 37% formalin (3.75 mol as formaldehyde (Compound 2)) was added dropwise over 90 minutes. After completion of the dropwise addition, stirring was continued for 1 hour for aging, followed by cooling to room temperature to obtain a liquid composition A having a solid content of 13.3% by mass. At this time, the pH of the composition A was 11.0, and the content of the compound 2 was 1% by mass or less based on the charged amount of the raw materials (compound 1, compound 2, alkyldiethanolamine, water, and so on). The molar ratio of compound 2 and compound 1 at the time of charging, compound 2 / compound 1 is 0.5, the total amount of compound 1 and compound 2 with respect to 100 parts by weight of the charged raw material is 12.87 parts by weight, water 86.5 parts by weight, The amount was 0.63 parts by mass of N-methyldiethanolamine. In the table, the reaction start pH is the pH of the reaction system when Compound 1 and Compound 2 first contact each other, and the reaction end pH is a reaction after 90 minutes of dropwise addition and further aging for 1 hour. The pH of the system, which corresponds to the pH of the composition obtained in this example (the same applies hereinafter). The amount of Compound 2 after 30 minutes and 1 hour after aging was measured, and the amount of Compound 2 was 0.8% by mass after 30 minutes and 0.6% by mass after 1 hour with respect to the total of the raw materials. It was. It was confirmed that the reduction amount of Compound 2 for 30 minutes was 0.3% by mass or less with respect to the total of the raw materials, and it was judged that the reaction was completed at the time of aging 1 hour.

<Production of Compositions B to D and a to d>
It was prepared in the same manner as in Composition A except that the amounts of Compound 1, Compound 2, and alkyldiethanolamine were changed to those shown in Table 1. However, the composition D was prepared by adding and mixing formalin into the flask in advance in the same manner as urea (the charging method in the table is indicated as “collective”). In the production of Composition D, the decrease amount of Compound 2 at the end of the reaction for 30 minutes was 0.3% by mass or less with respect to the total of the raw materials (Compound 1, Compound 2, alkyldiethanolamine, water).

<Production of Compositions E, F and e to g>
It was manufactured by the same method as that for Composition B except that the reaction temperature was changed to the temperature shown in Table 2. Table 2 also shows the conditions and results of Composition B.

<Manufacture of compositions hj>
Production was carried out in the same manner as in Composition B, except that N-methyldiethanolamine was changed to the compounds in Table 3. Table 3 also shows the conditions and results of Composition B.

<Manufacture of composition k>
13.5 g of powdered 1,3-bis (hydroxymethyl) urea (commercial product, Wako Pure Chemical Industries, Ltd., reagent) is dissolved in 86.5 g of distilled water, and composition Q having a solid content of 13.5% by mass (PH 7.4 at 20 ° C.) was prepared. The content of Compound 3 in the commercially available powder product was 46.4% by mass. 1,3-bis (hydroxymethyl) urea is in an equilibrium relationship with the structure of Compound 3 in the composition Q.

The following was used for each compound of Tables 1-3.
・ Urea: Wako Pure Chemical Industries, Reagent ・ Formalin: 37 mass% aqueous solution, Wako Pure Chemical Industries, reagent, N-methyldiethanolamine: Nippon Emulsifier Co., amino alcohol MDA
・ Triethanolamine: Wako Pure Chemical Industries, Reagent ・ Diethanolamine: Wako Pure Chemical Industries, Reagent ・ Monoethanolamine: Wako Pure Chemical Industries, Reagent

<Content of Condensate of Compound 2 and Compound 1>
The water content in the liquid composition was determined by the Karl Fischer method, and the mass of components other than water was defined as the solid content. The urea content in the liquid composition was determined by liquid chromatography, and the formaldehyde content in the liquid composition was similarly determined by liquid chromatography, and the urea and formaldehyde contents were subtracted from the solid content. The amount was the content of the condensate of compound 2 and compound 1 in the liquid composition.

<Measurement of content of compound 3 in condensate>
A part (about 20 g) of the obtained composition was powdered by lyophilization. Next, the content of tetrahydro-4H-1,3,5-oxadiazin-4-one as compound 3 in the powder was determined by liquid chromatography mass spectrometry (LC / MS) using the powder as a 1 mass% aqueous solution. It was. Specifically, the peak of 120.0 (m / z) of compound 3 of mass spectrometry and 192.1, 221.9, 285.9, and 316.0 (m / z) of condensates other than compound 3 The content of compound 3 in the condensate was determined from the area of each peak of liquid chromatography corresponding to the peak of. The content of Compound 3 in the condensate in the table corresponds to the ratio of the peak area of the monomer in the liquid composition to the total value of the peak areas of the monomer and multimer. The content of Compound 3 in the liquid composition was determined from the amount of solid content in the liquid composition, the content of condensate in the solid content, and the content of Compound 3 in the condensate.

Liquid chromatography mass spectrometry condition column: Imtakt Union UK-Amino HT (length 150 mm, inner diameter 2 mm) 3 μ
Column temperature: 40 ° C
Mobile phase: A 0.01 mol / L ammonium acetate aqueous solution, C acetonitrile (gradient elution method)

<Storage stability test>
The resulting composition was placed in a 500 ml polypropylene bottle and stored at 40 ° C. After 1 day, 1 week, 1 month and 3 months from the start of storage, the appearance is visually observed. If the composition is free of precipitation or turbidity, A, if turbid, B, if there is precipitation, C. It was evaluated.

Compound 1: Urea compound 2: Formaldehyde MDEA: N-methyldiethanolamine

  It can be seen that the yield and storage stability of compound 3 are excellent when the molar ratio of compound 2 and compound 1 and compound 2 / compound 1 are in the range of 0.3 to 1.7.

Compound 1: Urea compound 2: Formaldehyde MDEA: N-methyldiethanolamine

  It can be seen that the yield and storage stability of Compound 3 are excellent when the reaction temperature is in the range of 15 ° C to 50 ° C.

* 1 The compound which is not the alkyldiethanolamine of the comparative example is also described in this column for convenience.
* 2 Indicates the content of Compound 3 in commercially available powder products.

Compound 1: Urea compound 2: Formaldehyde MDEA: N-methyldiethanolamine TEA: Triethanolamine DEA: Diethanolamine MEA: Monoethanolamine

  It can be seen that the yield and storage stability of compound 3 are excellent when alkyldiethanolamine is used and the pH during the reaction is 10.0 or more.

  In addition, the content of Compound 3 in the commercially available powdered product shown in the Reference Example is 46.4% by mass, and the liquid composition prepared from the commercially available powdered product has a pH of 7.4 and has excellent storage stability. You can see that it is inferior.

Test Example An iron and steel detergent was prepared using the components shown in Table 4, and the detergency for the steel sheet was evaluated.

<Preparation of steel cleaning agent>
(1) Preparation of Cleaning Agent A Polyoxyethylene (average 2 mole addition) -2-ethylhexyl ether 1.0 mass%, sodium polyacrylate (weight average molecular weight 6000) 5.0 mass in the ratio in the final cleaning agent %, Composition B 13.0 mass% (corresponding to 2.0 mass% as compound 3) and water 61.0 mass% were mixed to prepare an aqueous solution. Next, 20.0% by mass of sodium hydroxide was added to and mixed with the aqueous solution at a ratio in the final cleaning agent to obtain cleaning agent A.

(2) Preparation of Comparative Cleaning Agent B Except that Composition B was replaced with 2.0% by mass of sodium ethylenediaminetetraacetate known as a chelating agent, and the ratio of water was 72.0% by mass, Comparative cleaning agent B was prepared in the same manner as cleaning agent A.

(3) Preparation of Comparative Cleaning Agent C Comparative Cleaning Agent C was prepared in the same manner as Cleaning Agent A, except that Composition B and sodium ethylenediaminetetraacetate were not blended and the proportion of water was 74.0% by mass. did.

<Evaluation of detergency>
A steel plate piece (10 cm × 15 cm) to which the synthetic ester-based rolling oil is attached is immersed and washed in an aqueous solution of a cleaning agent diluted 20 times (cleaning liquid temperature 60 ° C., immersion time 1 second), and then electrolytic cleaning (cleaning liquid temperature 60 ° C.). Electrolytic time 1 second (+/- 0.5 seconds each), current density 10 A / dm ² (the initial negative electrode is a washed steel plate), and then water-wetting area on the steel plate surface after washing with a sufficient amount of running water As the water wetted area is closer to 100%, the higher the detergency is.

  It can be seen that the cleaning agent A has better cleaning properties than the comparative cleaning agents B and C, and the composition according to the production method of the present invention can be used as a chelating agent for the cleaning agent.

Claims (3)

In water, the compound 1 represented by the following formula (1) is reacted with the compound 2 represented by the following formula (2). The pH is 10.0 containing the compound 3 represented by the following formula (3) and water. A method for producing the above liquid composition,
The charged molar ratio of Compound 2 and Compound 1, Compound 2 / Compound 1 is 0.3 or more and 1.7 or less,
The reaction between Compound 1 and Compound 2 is carried out at 15 ° C. or higher and 50 ° C. or lower and in the presence of alkyldiethanolamine at pH 10.0 or higher.
A method for producing a liquid composition.

  2. The liquid composition according to claim 1, wherein the charged molar ratio of alkyldiethanolamine to the total of compound 1 and compound 2 and alkyldiethanolamine / (total of compound 1 and compound 2) is 0.005 or more and 0.10 or less. Manufacturing method.   The manufacturing method of the liquid composition of Claim 1 or 2 which adds the compound 2 to the mixture containing the compound 1, the alkyl diethanolamine, and water, and performs the reaction of the compound 1 and the compound 2.