Antifoaming agent

Abstract

To provide an antifoaming agent for use in a detergent for a medical instrument washer that can inhibit foam generation even when heated washing water is used.SOLUTION: An antifoaming agent comprises a compound represented by the general formula N+R4.X-. In the formula, each R is independently a C1-18 alkyl group, a benzyl group, or a group (Y) represented by -(AO)n-H, where AO is a C2-4 alkyleneoxy group and where n is a number from 1 to 5; and X- is a monovalent or divalent anionic counterion.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an antifoaming agent for use in a cleaning agent for a medical instrument washer. [Background technology]

[0002] Automatic cleaning machines have also been introduced for cleaning medical instruments. Various cleaning agents are known for use in such medical instrument cleaning machines (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 5407001 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, the higher the cleaning temperature, the higher the cleaning power. However, since the stains adhering to medical instruments are protein stains such as blood, if the cleaning temperature is high (e.g., 80°C or higher), the proteins will denature and the stains will become difficult to remove. Therefore, Patent Document 1 above proposes a detergent composition that has little foaming even at low temperatures (5°C) and has excellent cleaning power. However, cleaning at low temperatures may result in insufficient cleaning power. In light of these circumstances, we investigated detergents suitable for cleaning with water heated to a temperature lower than the denaturation temperature of proteins (for example, 50°C), but found that conventional detergents had a problem of foaming. It is believed that one of the causes of foaming is blood stains. An object of the present invention is to provide a defoaming agent for use in a detergent for a medical instrument washer, which is capable of suppressing the generation of foam even when heated washing water is used. [Means for solving the problem]

[0005] The present inventors have conducted extensive research to solve the above problems and have arrived at the present invention. That is, the present invention is as follows. [1] A defoaming agent for use in a cleaning agent for a medical instrument washer, comprising a compound represented by the following general formula (1):

[0006] [ka] (In the formula, R 1 , R 2 , R 3 , R 4 are each independently an alkyl group having 1 to 18 carbon atoms, a benzyl group, or a group (Y) represented by -(AO)nH, AO is an alkyleneoxy group having 2 to 4 carbon atoms, n is a number from 1 to 5, and X - is a monovalent or divalent anionic counterion. [2] R in general formula (1) 1 , R 2 , R 3 , R 4 wherein at least one of the groups is an alkyl group having 6 to 18 carbon atoms or a benzyl group. [3] R in general formula (1) 1 , R 2 , R 3 , R 4 The antifoaming agent according to [1] or [2], wherein at least one of the groups represented by the formula (Y) is an alkyl group having 1 to 3 carbon atoms or a group represented by -(AO)nH. [4] R in general formula (1) 1 , R 2 , R 3 , R 4 The defoaming agent according to any one of [1] to [3], wherein at least one of the groups is an alkyl group having 8 to 10 carbon atoms. [5] X in general formula (1) - is a lactate ion, an adipic acid ion, or a methyl sulfate ion. [6] The defoaming agent according to any one of [1] to [5], further comprising a nonionic surfactant. Effect of the Invention

[0007] According to the present invention, there is provided a defoaming agent for use in a detergent for a medical instrument washer, which is capable of suppressing the generation of foam even when heated washing water is used. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The antifoaming agent of the present invention is an antifoaming agent used in a cleaning agent for a medical instrument washer. The antifoaming agent of the present invention contains a compound represented by the following general formula (1):

[0009] [ka]

[0010] In the general formula (1), R 1 , R 2 , R 3 , R 4 are each independently an alkyl group having 1 to 18 carbon atoms, a benzyl group, or a group (Y) represented by -(AO)nH.

[0011] Specific examples of the alkyl group having 1 to 18 carbon atoms include methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl groups. The alkyl group having 1 to 18 carbon atoms may be a linear alkyl group or a branched alkyl group. In addition, it may be an alkyl group having a carbon number distribution, such as an alkyl group derived from an aliphatic alcohol obtained by reducing a fatty acid obtained from coconut oil (coconut oil alkyl group, mainly an alkyl group having 12 to 14 carbon atoms).

[0012] In the group (Y) represented by -(AO)nH, AO is an alkyleneoxy group having 2 to 4 carbon atoms. Examples of AO include an ethyleneoxy group, a propyleneoxy group, and a butyleneoxy group. The propyleneoxy group and the butyleneoxy group may be linear or branched. In the group (Y) represented by -(AO)nH, n is a number from 1 to 5. When there are two or more AO, the AO may be one type or a combination of two or more types. As AO, those containing an ethyleneoxy group are preferred.

[0013] In the general formula (1), X - is a monovalent or divalent anionic counterion. X - Examples of the cations include lactate ion, adipic acid ion, methyl sulfate ion, chloride ion, etc. Among these, lactate ion, adipic acid ion, and methyl sulfate ion are preferred from the viewpoint of antifoaming properties.

[0014] From the viewpoint of excellent antifoaming properties, the compound represented by the general formula (1) is preferably R 1 , R 2 , R 3 , R 4 At least one of the groups is an alkyl group having 6 to 18 carbon atoms or a benzyl group; R 1 , R 2 , R 3 , R 4 At least one of the groups is an alkyl group having 1 to 3 carbon atoms or a group (Y) represented by -(AO)nH, and X - It is preferable that R in the general formula (1) is a compound that satisfies at least one of lactate ion, adipic acid ion, and methyl sulfate ion. 1 , R 2 , R 3 , R 4 at least one of the three groups is an alkyl group having 8 to 10 carbon atoms, and at least one of the remaining three groups is an alkyl group having 1 to 3 carbon atoms. The compounds represented by general formula (1) may be used singly or in combination of two or more kinds.

[0015] The compound represented by general formula (1) can be produced, for example, by the following production method. The following production method is an example, and the present invention is not limited thereto. Hereinafter, the "compound represented by general formula (1)" is also referred to as "compound (A)".

[0016] The compound (A) is represented by the general formula (1) R 1 , R 2 , R 3 , R 4 are each independently an alkyl group having 1 to 18 carbon atoms or a benzyl group, and X - In the case of compounds where R is a chloride ion, the compound can be obtained by reaction of a tertiary amine (eg, didecylmethylamine) with an alkylating agent (such as methyl chloride and benzyl chloride).

[0017] The compound (A) is represented by the general formula (1) R 1 , R 2 , R 3 , R 4 One of the groups (Y) is represented by -(AO)nH, and the other three groups are each independently an alkyl group having 1 to 18 carbon atoms, and X - In the case of a compound in which is a lactate ion, the compound can be obtained by adding an alkylene oxide having 2 to 4 carbon atoms to a tertiary amine (for example, didecylmethylamine) in the presence of water and lactic acid.

[0018] The compound (A) is represented by the general formula (1) R 1 , R 2 , R 3 , R 4 are each independently an alkyl group having 1 to 18 carbon atoms; - In the case of a compound in which R is an adipic acid ion, the compound can be obtained by converting a tertiary amine (such as didecylmethylamine) into a quaternary amine with dimethyl carbonate and then reacting it with an organic acid.

[0019] The defoaming agent of the present invention may further contain a nonionic surfactant. The nonionic surfactant is not particularly limited, but may be, for example, an aliphatic polyether surfactant (e.g., an alkylene oxide adduct of a higher alcohol, etc.). As the nonionic surfactant, a commercially available product may be used. An example of a commercially available product is Plurafac LF403 (manufactured by BASF).

[0020] The defoaming agent of the present invention may contain, in addition to the compound represented by general formula (1), water, an organic solvent (ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, methanol, ethanol, 1-propanol, 2-propanol, etc.), a salt (sodium chloride, calcium chloride, sodium sulfate, didecylmethylamine lactate, etc.), and the like.

[0021] The content of the compound represented by general formula (1) in the defoaming agent of the present invention is preferably 1 wt % to 100 wt %, and more preferably 8.5 wt % to 84 wt %, based on the weight of the defoaming agent, from the viewpoint of defoaming properties.

[0022] From the viewpoint of cleaning properties, the content of the nonionic surfactant in the defoaming agent of the present invention is preferably 0% by weight to 99% by weight based on the weight of the defoaming agent.

[0023] The content of water and / or organic solvent in the defoaming agent of the present invention is preferably 0% by weight to 70% by weight based on the weight of the defoaming agent, from the viewpoint of easy mixing with a cleaning agent (details will be described later).

[0024] The defoaming agent of the present invention, when used together with a cleaning agent, has the effect of preventing foam generation during cleaning and of eliminating generated foam. There is no particular limitation on the cleaning agent used together with the defoaming agent of the present invention, so long as it can be used as a cleaning agent for a medical instrument cleaning device. It is preferable that the defoaming agent of the present invention is used in combination with a cleaning agent for a medical instrument cleaning device. The method of mixing the cleaning agent for a medical instrument cleaning device and the defoaming agent of the present invention is not particularly limited, and can be carried out using a known device.

[0025] The amount of the defoaming agent of the present invention used is preferably such that the ratio of the compound of general formula (1) to the total weight of the cleaning agent and the defoaming agent is 0.05% by weight or more, more preferably 0.1% by weight or more, from the viewpoint of defoaming properties at 50° C. From the viewpoint of cleaning properties, the amount is preferably such that the ratio of the compound of general formula (1) to the total weight of the cleaning agent and the defoaming agent is 1.0% by weight or less, more preferably 0.5% by weight or less. EXAMPLES

[0026] <Production Example 1> In an autoclave equipped with a stirrer, a thermometer, a pressure gauge, a pressure-resistant dropping cylinder, and a line for reducing pressure and introducing nitrogen, 312 parts (1 mol) of didecylmethylamine, 90 parts (1 mol) of a 90% by weight aqueous lactic acid solution, and 26 parts of water were added, stirring was started, and the temperature was raised to 80°C. Next, 88 parts (2 mol) of ethylene oxide were dropped at a pressure of 0.3 MPaG or less over a period of 4 hours, and the mixture was stirred at the same temperature for 1 hour until the pressure was equilibrated, thereby obtaining a solution (a-1) containing compound (A-1). The concentration of solids in the solution (a-1) was 84% ​​by weight. Compound (A-1) is didecylmethylpolyoxyethyleneammonium lactate [R in general formula (1)] 1 and R 2 is a decyl group, R 3 is a methyl group, R 4 is a group represented by -(EO)nH, n is 2, X - is a lactate ion] and is a compound represented by general formula (1). In this specification, the term "solid content" refers to the residue remaining after 1 g of a sample is placed in an uncovered glass petri dish and dried at 105°C for 90 minutes in a circulating air dryer.

[0027] <Production Example 2> In an autoclave equipped with a stirrer, a thermometer, a pressure gauge, a pressure-resistant dropping cylinder, a vacuum line and a nitrogen introduction line, 312 parts (1 mol) of didecylmethylamine, 269 parts (3 mol) of dimethyl carbonate, and 108 parts of methanol were added, and stirring was started to carry out a reaction at 120°C for 20 hours. Then, the mixture was transferred to a Kolben and concentrated under heating at 90°C, and the concentrate was added dropwise to an aqueous adipic acid solution in which 71 parts (0.5 parts) of adipic acid was dissolved in 543 parts of water at 70°C over 1 hour, and the mixture was further reacted at 70°C for 1 hour. The mixture was concentrated under reduced pressure at 60°C for 5 hours to obtain a solution (a-2) containing compound (A-2). The concentration of solids in the solution (a-2) was 50% by weight. Compound (A-2) was found to be didecyldimethylammonium adipate [R in general formula (1)]. 1 and R 2 is a decyl group, R 3 and R 4 is a methyl group, X - is an adipic acid ion] and is a compound represented by general formula (1).

[0028] <Production Example 3> Into an autoclave equipped with a stirrer, a thermometer, a pressure gauge, a pressure-resistant dropping cylinder, and a line for reducing pressure and introducing nitrogen, 312 parts (1 mol) of didecylmethylamine, 55 parts of denatured alcohol (Solmix HP-1, manufactured by Japan Alcohol Sales Co., Ltd.), and 77 parts of water were added, stirring was started, and 125 parts (1 mol) of dimethyl sulfate was added dropwise at 30°C to obtain a solution (a-3) containing compound (A-3). The solid content in the solution (a-3) was 75% by weight. Compound (A-3) is didecyldimethylammonium methyl sulfate [R in general formula (1)]. 1 and R 2 is a decyl group, R 3 and R 4 is a methyl group, X - is a methyl sulfate ion] and is a compound represented by general formula (1).

[0029] <Production Example 4> In an autoclave equipped with a stirrer, a thermometer, a pressure gauge, a pressure-resistant dropping cylinder, and a line for reducing pressure and introducing nitrogen, 312 parts (1 mole part) of didecylmethylamine, 40 parts of ethanol, and 40 parts of water were added, stirring was started, and methyl chloride was added dropwise at 60°C to obtain a solution (a-4) containing compound (A-4). The solid concentration in the solution (a-4) was 80% by weight. Compound (A-4) was prepared by the reaction of didecyldimethylammonium chloride [R in general formula (1)]. 1 and R 2 is a decyl group, R 3 and R 4 is a methyl group, X - is a chloride ion] and is a compound represented by general formula (1).

[0030] <Production Example 5> In an autoclave equipped with a stirrer, thermometer, pressure gauge, pressure-resistant dropping cylinder, and vacuum and nitrogen introduction lines, 228 parts (1 mol) of coconut oil alkyl dimethylamine and 42 parts of water were added and stirring was started, and 125 parts (1 mol) of benzyl chloride and 300 parts of water were added dropwise at 50°C over 2 hours to obtain a solution (a-5) containing compound (A-5). The solid concentration in the solution (a-5) was 51% by weight. Compound (A-5) is coconut oil alkyl dimethyl benzyl ammonium chloride [R in general formula (1)]. 1 is a coconut oil alkyl group (including alkyl groups having 12 to 14 carbon atoms), R 2 and R 3 is a methyl group, R 4 is a benzyl group, X - is a chloride ion] and is a compound represented by general formula (1).

[0031] <Production Example 6> 270 parts (1 mol) of hexadecyldimethylamine and 708 parts of water were added to an autoclave equipped with a stirrer, a thermometer, a pressure gauge, a pressure-resistant dropping bomb, and a line for reducing pressure and introducing nitrogen, and stirring was started. 49 parts (1 mol) of methyl chloride was added dropwise at 90°C over 2 hours to obtain a solution (a-6) containing compound (A-6). The solid concentration in the solution (a-6) was 30% by weight. Compound (A-6) is hexadecyltrimethylammonium chloride [R in general formula (1)]. 1 is a hexadecyl group, R 2 , R 3 and R 4 is a methyl group, X - is a chloride ion] and is a compound represented by general formula (1).

[0032] <Preparation of defoamers of Examples 1 to 14> In Examples 1 to 12 and 14, the solutions containing the compounds represented by general formula (1) of the types shown in Table 1 were used as defoaming agents as they were. For Example 13, 1 part by weight of a nonionic surfactant was added to 0.12 parts by weight of a solution (a-1) containing a compound represented by general formula (1) and mixed for 1 minute to prepare a defoaming agent. Cleaning compositions were prepared for the defoaming agents of Examples 1 to 14, and the following evaluation tests were carried out. The results are shown in Table 1.

[0033] <Preparation of cleaning composition> For Examples 1 to 12 and 14, the type of solution (a) shown in Table 1 was added in the amount shown in Table 1 to the amount of medical instrument detergent (C) shown in Table 1 and mixed for 1 minute to prepare the detergent composition. For Example 13, 1.12 parts by weight of an antifoaming agent [an antifoaming agent consisting of 0.12 parts by weight of a solution (a-1) containing a compound represented by general formula (1) and 1 part by weight of a nonionic surfactant] was added to 98.88 parts by weight of a medical instrument detergent (C-1) and mixed for 1 minute to prepare a detergent composition.

[0034] <Evaluation test> (1) Evaluation of antifoaming properties 0.70 g of sheep blood (Kohjin Bio Co., Ltd., heparin-treated whole sheep blood) was added to 10 g of each detergent composition, and the mixture was heated at 60°C for 10 minutes and then placed in a dishwasher (IAGREEA, "IA-DW01") to start the washing process. The state of the liquid surface immediately after stopping the wash, when it reached 20°C after about 1 minute and when it reached 50°C after about 13 minutes, was visually observed, and the defoaming property was evaluated according to the following evaluation criteria. In the following evaluation criteria, "immediately" means within 1 second of foam generation. The defoaming ability is ranked in the order of excellent, followed by ◯, ◯, and △ (◎ being the best). [Evaluation Criteria] ◎: The area ratio of bubbles on the liquid surface is less than 10% and the bubbles break immediately. ○: The area ratio of bubbles on the liquid surface is 10% or more but less than 20%. △: The area ratio of bubbles on the liquid surface is 20% or more but less than 70%. ×: The area ratio of bubbles to the liquid surface is 70% or more.

[0035] (2) Evaluation of cleaning ability In a plastic beaker, 1 g of each detergent composition was diluted with 99 g of water to prepare a cleaning solution. A cleaning evaluation indicator TOSI (manufactured by PEREG GmbH) was immersed in the cleaning solution, the temperature of which was adjusted to 50°C using a water bath, and fixed in the plastic beaker. The solution was then stirred at 50°C and 1000 rpm for 30 minutes, and rinsed with water. The amount of blood stains remaining on the indicator TOSI was visually observed and evaluated according to the following criteria. If it was △ or ◯, it was determined that there was cleaning ability. The order of cleaning ability is excellent, from ◯ to △. [Evaluation Criteria] ○: The amount of blood stain remaining is less than 10% of the amount before washing. △: The amount of remaining blood stains is between 10% and 50% of the amount before washing. ×: Remaining blood stain is 50% or more.

[0036] Details of the compounds shown in Table 1 are as follows. <Solution (a) containing the compound represented by general formula (1)> (a-1) A solution containing the compound (A-1) produced in Production Example 1 (a-2) Solution containing compound (A-2) produced in Production Example 2 (a-3) Solution containing compound (A-3) produced in Production Example 3 (a-4) Solution containing compound (A-4) prepared in Preparation Example 4 (a-5) Solution containing compound (A-5) produced in Production Example 5 (a-6) Solution containing compound (A-6) prepared in Preparation Example 6 <Nonionic surfactant (B)> (B-1): Plurafac LF403 (manufactured by BASF) <Medical equipment cleaning agent (C)> (C-1): Power Quick Jet Ultrasonic Dual Purpose Cleaner S (manufactured by Saraya Co., Ltd.) (C-2): Neo Albest S (manufactured by Albose Co., Ltd.)

[0037] [Table 1]

[0038] As shown in Table 1, in Examples 1 to 14 in which the antifoaming agent of the present invention was used, foaming was suppressed more in washing at 50° C. than in Comparative Examples 1 and 2 in which no antifoaming agent was used. This result shows that the present invention can provide an antifoaming agent for use in a cleaning agent for medical instrument washing machines that can suppress foaming even when heated washing water is used.

Claims

1. A defoaming agent for use in a cleaning agent for a medical instrument washer, comprising a compound represented by the following general formula (1): 【Chemistry 1】 (In the formula, R １ , R ２ , R ３ , R ４ are each independently an alkyl group having 1 to 18 carbon atoms, a benzyl group, or a group (Y) represented by -(AO)n-H, AO is an alkyleneoxy group having 2 to 4 carbon atoms, n is a number from 1 to 5, and X － is a monovalent or divalent anionic counterion.

2. R in general formula (1) １ , R ２ , R ３ , R ４ 2. The defoaming agent according to claim 1, wherein at least one of the groups is an alkyl group having 6 to 18 carbon atoms or a benzyl group.

3. R in general formula (1) １ , R ２ , R ３ , R ４ The defoaming agent according to claim 1 or 2, wherein at least one of the groups (Y) is an alkyl group having 1 to 3 carbon atoms or a group represented by -(AO)n-H.

4. R in general formula (1) １ , R ２ , R ３ , R ４ The defoaming agent according to claim 1 or 2, wherein at least one of the groups is an alkyl group having 8 to 10 carbon atoms.

5. X in general formula (1) － 3. The defoaming agent according to claim 1 or 2, wherein is a lactate ion, an adipic acid ion or a methyl sulfate ion.

6. The defoaming agent according to claim 1 or 2, further comprising a nonionic surfactant.

Images