JP6389989B2 - Antifoam - Google Patents

Description

  The present invention relates to an antifoaming agent.

  A fatty acid metal salt (A), a polyoxyalkylene compound (B) and a polyhydric alcohol fatty acid ester (C) are contained, and the fatty acid metal salt (A), the polyoxyalkylene compound (B) and a polyhydric alcohol fatty acid ester Based on the total weight of (C), the content of (A) is 0.1 to 10% by weight, the content of (B) is 5 to 50% by weight, and the content of (C) is 40 to 94% by weight. An antifoaming agent (Patent Document 1) is known.

Japanese Patent No. 5540177

  The antifoaming agent has a problem that the antifoaming property may be low. An object of this invention is to provide the antifoamer which has the more excellent antifoaming property.

Features of the defoaming agent of the present invention, higher fatty acid monoester of polyoxyethylene glycol (A), higher fatty acid diesters of polyoxyethylene glycol (B), a polyoxyalkylene monobutyl ether (C), a higher fatty acid (D), ethylenebis stearyl amide (E) and 25 ° C. in liquid base oil (F) seen including,
The polymerization degree of polyoxyethylene glycol is an integer of 13 to 40,
The higher fatty acid has 16 to 18 carbon atoms,
Polyoxyethylene glycol higher fatty acid monoester (A), polyoxyethylene glycol higher fatty acid diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), ethylene bisstearyl amide (E) and 25 ° C. Based on the total weight of the liquid base oil (F), the content of the higher fatty acid monoester (A) of polyoxyethylene glycol is 2 to 12% by weight, the content of the higher fatty acid diester (B) of polyoxyethylene glycol 2 to 12% by weight, polyoxyalkylene monobutyl ether (C) content is 2 to 12% by weight, higher fatty acid (D) content is 0.3 to 2% by weight, ethylene bisstearylamide (E content of 1-6% by weight of), the content of the liquid base oil (F) at 25 ° C. is 60 to 88 wt% <br/> The the gist.

  The antifoaming agent of the present invention exhibits more excellent defoaming properties.

  The monoester (A) of polyoxyalkylene glycol includes a monoester of polyoxyalkylene glycol and higher fatty acid.

  The oxyalkylene group constituting the polyoxyalkylene glycol includes an oxyalkylene group having 2 to 4 carbon atoms, and examples thereof include oxyethylene, oxypropylene, and oxybutylene. Of these, oxyethylene and oxypropylene are preferable from the viewpoint of defoaming properties, and oxyethylene is more preferable.

  The polyoxyalkylene group may contain two or more oxyalkylene groups. When two or more kinds of oxyalkylene groups are contained, any of block, random and a mixture thereof may be used, but a block of oxyethylene and oxypropylene is preferable.

  The degree of polymerization of the polyoxyalkylene group is preferably an integer of 2 to 60, more preferably an integer of 3 to 45, and particularly preferably an integer of 4 to 30 from the viewpoint of defoaming properties.

  The higher fatty acid includes a saturated fatty acid having 12 to 30 carbon atoms and an unsaturated fatty acid.

  Saturated fatty acids include straight chain saturated fatty acids and branched chain saturated fatty acids.

  Examples of the linear saturated fatty acid include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, serotic acid, and melicic acid. Examples of the branched saturated fatty acid include isostearic acid.

  As unsaturated fatty acid, linear unsaturated fatty acid and branched unsaturated fatty acid can be used.

  Examples of the linear unsaturated fatty acid include myristoleic acid, palmitoleic acid, oleic acid and triacontenoic acid, and examples of the branched chain unsaturated fatty acid include isomiristoleic acid and isooleic acid.

  Of these, from the viewpoint of defoaming properties, linear saturated fatty acids and linear unsaturated fatty acids are preferable, and lauric acid, myristic acid, palmitic acid, stearic acid, crotonic acid, heptenoic acid, myristoleic acid, palmitolein are more preferable. Acids, oleic acid, erucic acid, linoleic acid and linolenic acid, particularly preferably myristic acid, palmitic acid, stearic acid, myristoleic acid, palmitoleic acid, oleic acid, erucic acid, linoleic acid and linolenic acid, most preferably palmitic acid , Stearic acid, palmitoleic acid, oleic acid, erucic acid, linoleic acid and linolenic acid.

  These fatty acids may be a single component or may contain a plurality of fatty acids.

Examples of the polyoxyalkylene glycol monoester (A) include polyoxyethylene glycol monopalmitate, polyoxyethylene glycol monostearate, polyoxyethylene glycol monopalmitoleate, polyoxyethylene glycol monooleate, polyoxyethylene glycol monopalmitate, Preferred examples include oxyethylene glycol monolinoleate and polyoxypropylene glycol monooleate.
The monoester (A) of polyoxyalkylene glycol can be easily obtained from the market or can be produced by a known method.

   The content (% by weight) of polyoxyalkylene glycol monoester (A) is as follows: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), Based on the total weight of the fatty acid (D), the fatty acid amide (E) and the base oil (F) which is liquid at 25 ° C., 0.1 to 20 is preferable, more preferably 1 to 15, particularly preferably 2 to 12. is there. In this range, the defoaming property is further improved.

  The diester (B) of polyoxyalkylene glycol includes a diester of polyoxyalkylene glycol and higher fatty acid.

Examples of the polyoxyalkylene glycol diester (B) include polyoxyethylene glycol dipalmitate, polyoxyethylene glycol distearate, polyoxyethylene glycol dipalmitoleate, polyoxyethylene glycol dioleate, polyoxyethylene Preferable examples are glycol dilinoleic acid ester and polyoxypropylene glycol dioleic acid ester.
The diester (B) of polyoxyalkylene glycol can be easily obtained from the market or can be produced by a known method.

   The content (% by weight) of the polyoxyalkylene glycol diester (B) is: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid Based on the total weight of (D), fatty acid amide (E) and base oil (F) which is liquid at 25 ° C., 0.1 to 20 is preferable, more preferably 1 to 15, and particularly preferably 2 to 12. .

  Examples of the polyoxyalkylene monobutyl ether (C) include monoethers (or alkylene oxide adducts of butyl alcohol) of polyoxyalkylene glycol and butyl alcohol (or halogenated butyl, butyl sulfate, dibutyl carbonate, etc.).

Preferable examples of polyoxyalkylene monobutyl ether (C) include polyoxyethylene monobutyl ether and polyoxypropylene monobutyl ether.
Polyoxyalkylene monobutyl ether (C) can be easily obtained from the market or can be produced by a known method.

   The content (% by weight) of polyoxyalkylene monobutyl ether (C) is as follows: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid ( Based on the total weight of D), fatty acid amide (E) and base oil (F) which is liquid at 25 ° C., 0.5 to 20 is preferable, 1 to 15 is more preferable, and 2 to 12 is particularly preferable.

  As the higher fatty acid (D), the above higher fatty acids can be used, and the preferred range is also the same.

   The content (% by weight) of the higher fatty acid (D) is as follows: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), Based on the total weight of the fatty acid amide (E) and the base oil (F) which is liquid at 25 ° C., 0.1 to 3 is preferable, more preferably 0.2 to 2.5, and particularly preferably 0.3 to 2. It is.

  As fatty acid amide (E), the reaction product (fatty acid diamide) of C1-C6 alkylenediamine or alkenylenediamine and C10-C22 fatty acid and / or C1-C22 alkylamine, C1-C1 A reaction product (fatty acid monoamide) of -22 alkenylamine or ammonia and a fatty acid having 10 to 22 carbon atoms is included.

  Examples of fatty acid diamides include ethylene bisstearylamide, ethylene bispalmitylamide, ethylene bismyristylamide, ethylene bislaurylamide, ethylene bisoleylamide, propylene bisstearylamide, propylene bispalmitylamide, propylene bismyristylamide, propylene bislauryl Amide, propylene bis oleyl amide, butylene bis stearyl amide, butylene bis palmityl amide, butylene bis myristyl amide, butylene bis lauryl amide, butylene bis oleyl amide, methylene bis lauryl amide, methylene bis stearyl amide, hexamethylene bis stearyl amide, etc. Can be mentioned.

  Examples of the fatty acid monoamide include N-stearyl stearyl amide, oleic acid amide, erucic acid amide, and stearyl amide.

  Of these, fatty acid diamide is preferable from the viewpoint of antifoaming property, more preferably ethylene bisstearylamide, ethylene bispalmitylamide, ethylene bislaurylamide, methylene bisstearylamide, and hexamethylene bisstearylamide, particularly preferably ethylene. Bisstearylamide, ethylenebispalmitylamide and ethylenebismyristylamide.

   The content (% by weight) of the fatty acid amide (E) is as follows: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), Based on the total weight of the fatty acid amide (E) and the base oil (F) that is liquid at 25 ° C., 0.1 to 8 is preferable, 0.5 to 7 is more preferable, and 1 to 6 is particularly preferable.

  The base oil (F) which is liquid at 25 ° C. includes mineral oil, fats and oils and monoalcohol fatty acid esters.

  Mineral oil can be refined by appropriately combining vacuum distillation, oil removal, solvent extraction, hydrocracking, solvent dewaxing, sulfuric acid washing, clay refining, and hydrorefining. Pure Spin G, Cosmo Pure Spin E, Cosmo SP-10, Cosmo SP-32 and Cosmo SC22 (Cosmo Oil Co., Ltd., “Cosmo” and “Pure Spin” are registered trademarks of the company), MC Oil P -22, S-10S (above, Idemitsu Kosan Co., Ltd.), stanol 40 (Exxon Mobil Corporation) and the like.

  Fats and oils include fatty acid having 6 to 22 carbon atoms or ester of glycerin with this mixture, vegetable oil (rapeseed oil, trade name such as rapeseed oil; Nisshin Oilio Group, soybean oil, palm oil, coconut oil, Olive oil, etc.), medium chain fatty acid glycerides (trade names, for example, Panacet 875; NOF Corporation, “Panasate” is a registered trademark of the company), fish oil, and the like.

  Examples of monoalcohol fatty acid esters include fatty acids having 6 to 22 carbon atoms or mixtures thereof and esters of monoalcohols having 1 to 22 carbon atoms that are liquid at 25 ° C., such as methyl oleate and butyl oleate. And methyl isostearate.

  Of the base oil (F) that is liquid at 25 ° C., mineral oils and fats and oils are preferable from the viewpoint of defoaming properties, and oils and fats are more preferable.

   The content (% by weight) of the liquid base oil (F) at 25 ° C. is as follows: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), Based on the total weight of fatty acid (D), fatty acid amide (E) and base oil (F) which is liquid at 25 ° C., 40 to 99 are preferred, 50 to 93 are more preferred, and 60 to 88 are particularly preferred.

  The antifoaming agent of the present invention includes polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), fatty acid amide (E). In addition to the base oil (F) which is liquid at 25 ° C., water and / or a product stabilizer {an antifungal agent, an antiseptic agent, an antirust agent and an antioxidant} may be contained.

  When water is contained, the content (% by weight) is determined by the following: polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D) Based on the total weight of the fatty acid amide (E) and the base oil (F) which is liquid at 25 ° C., 0.1 to 55 is preferable, 1 to 50 is more preferable, and 2 to 40 is particularly preferable.

  When the product stabilizer is contained, the content (% by weight) is determined by the polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid ( D), based on the total weight of the fatty acid amide (E) and the base oil (F) which is liquid at 25 ° C., preferably 0.01 to 20, more preferably 0.05 to 15, particularly preferably 0.1 to 10.

  The antifoaming agent of the present invention comprises polyoxyalkylene glycol monoester (A), polyoxyalkylene glycol diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), fatty acid amide (E) and The production method is not limited as long as it contains a liquid base oil (F) at 25 ° C. and, if necessary, water and / or a product stabilizer, but it is preferable that these components are uniformly mixed. .

  When the components of the antifoaming agent of the present invention are uniformly mixed, all or part of the components other than the fatty acid amide (E) and the fatty acid amide (E) at a temperature equal to or higher than the melting point of the fatty acid amide (E). It is preferable to include the process of mixing.

  The antifoaming agent of the present invention is effective for water-based foaming liquid {for example, drainage, white paper making process, water-based paint, etc.}, but particularly effective for water-based paint.

  The amount of the antifoaming agent of the present invention can be appropriately increased or decreased depending on the composition, temperature, concentration, etc. of the foaming liquid (additive), but is 0.01 based on the weight of the foaming liquid (additive). Is preferably 10 to 10% by weight, more preferably 0.05 to 5% by weight, and particularly preferably 0.1 to 2% by weight.

  Hereinafter, unless otherwise specified, “parts” means parts by weight and “%” means percent by weight.

<Example 1>
Liquid base oil (f1) at 25 ° C. {Corn oil, Nissin Oilio Group Co., Ltd.} 88 parts and fatty acid amide (e1) {Ethylenebisstearylamide, Alflow H-50S, NOF Corporation, “Alflow” Is a registered trademark. } After 1 part was uniformly mixed at 150 ° C., the mixture was cooled to 30 ° C. with stirring to obtain a mixed solution. The mixture was homogenized at 4000 rpm with a homogenizer (High Flex Disperser HG-92G, Taitec Co., Ltd.) to obtain a fatty acid amide dispersion. Polyoxyalkylene glycol monoester (a1) {polyoxyethylene (degree of polymerization: 35) glycol and palmitic acid monoester} 2 parts, polyoxyalkylene glycol diester (b1) {polyoxyalkylene glycol monoester (a1) 6.7 parts of diester of oxyethylene (degree of polymerization: 35) glycol and palmitic acid}, 2 parts of polyoxyalkylene monobutyl ether (c1) {polyoxypropylene monobutyl ether, Sigma Aldrich Japan GK} and higher fatty acid (d1) {Palmitic acid, Miyoshi Oil & Fat Co., Ltd.} 0.3 part was added and stirred and mixed uniformly to obtain the antifoaming agent (1) of the present invention.

  The polyoxyalkylene glycol monoester (a1) and the polyoxyalkylene glycol diester (b1) were synthesized by known alkylene oxide addition reaction and esterification reaction.

<Example 2>
"88 parts of liquid base oil (f1) at 25 ° C", "1 part of fatty acid amide (e1)", "2 parts of monoester of polyoxyalkylene glycol (a1)", "diester of polyoxyalkylene glycol (b1) "6.7 parts", "2 parts of polyoxyalkylene monobutyl ether (c1)" and "0.3 parts of higher fatty acid (d1)" are mixed with "base oil (f2) liquid at 25 ° C {Cosmo Pure Spin G, Cosmo Petroleum Corporation, “Pure Spin” is a registered trademark of the company. } 60 parts "," 2 parts fatty acid amide (e1) "," polyester of polyoxyalkylene glycol (a2) {polyester of polyoxyethylene (degree of polymerization: 40) glycol and stearic acid} 12 parts "," Polyester of polyoxyalkylene glycol (b2) {polyester of polyoxyethylene (degree of polymerization: 40) glycol and stearic acid} 12 parts ", 12 parts of polyoxyalkylene monobutyl ether (c1)" and "higher fatty acid (d2) The antifoaming agent (2) of the present invention was obtained in the same manner as in Example 1 except that it was changed to {2 parts of {Stearic acid, Miyoshi Oil Co., Ltd.}.

  The polyoxyalkylene glycol monoester (a2) and the polyoxyalkylene glycol diester (b2) were synthesized by known alkylene oxide addition reaction and esterification reaction.

<Example 3>
"88 parts of liquid base oil (f1) at 25 ° C", "1 part of fatty acid amide (e1)", "2 parts of monoester of polyoxyalkylene glycol (a1)", "diester of polyoxyalkylene glycol (b1) "6.7 parts", "2 parts of polyoxyalkylene monobutyl ether (c1)" and "0.3 parts of higher fatty acid (d1)" were added to "base oil (f3) liquid at 25 ° C {soybean oil, Nissin Oilio Group Co., Ltd.} 79.7 parts ”,“ Fatty Acid Amide (e2) {Ethylenebisstearylamide, Nippon Kasei Co., Ltd.} 6 parts ”,“ Polyoxyalkylene glycol monoester (a3) {Polyoxyethylene (degree of polymerization: 40) Monoester of glycol and oleic acid} 2 parts ”,“ polyester of polyoxyalkylene glycol (b3) {polyoxyethylene (degree of polymerization: 40 ) Diester of glycol and oleic acid} 2 parts ”,“ polyoxyalkylene monobutyl ether (c1) 10 parts ”and“ higher fatty acid (d3) {oleic acid, Miyoshi Oil & Fat Co., Ltd.} 0.3 part ” The antifoaming agent (3) of the present invention was obtained in the same manner as Example 1 except for the above.

  The polyoxyalkylene glycol monoester (a3) and the polyoxyalkylene glycol diester (b3) were synthesized by known alkylene oxide addition reaction and esterification reaction.

<Example 4>
"88 parts of liquid base oil (f1) at 25 ° C", "1 part of fatty acid amide (e1)", "2 parts of monoester of polyoxyalkylene glycol (a1)", "diester of polyoxyalkylene glycol (b1) "6.7 parts", "2 parts of polyoxyalkylene monobutyl ether (c1)" and "0.3 parts of higher fatty acid (d1)" are added to a base oil (f4) that is liquid at 25 ° C {rapeseed oil, Nisshin Oillio Group Co., Ltd.} 84.5 parts ”,“ fatty acid amide (e1) 4 parts ”,“ polyoxyalkylene glycol monoester (a4) {polyoxyethylene (degree of polymerization: 13) glycol and oleic acid monoester} 2 Part "," diester of polyoxyalkylene glycol (b4) {polyester of polyoxyethylene (degree of polymerization: 13) glycol and oleic acid} 5 parts "," The antifoaming agent (4) of the present invention was obtained in the same manner as in Example 1 except that the polyoxyalkylene monobutyl ether (c1) was changed to 4 parts and the higher fatty acid (d3) was 0.5 parts.

  The polyoxyalkylene glycol monoester (a4) and polyoxyalkylene glycol diester (b4) were synthesized by known alkylene oxide addition reaction and esterification reaction.

<Comparative Example 1>
In accordance with Example 1 of Patent Document 1, magnesium distearate (Olabrite MA-76, NOF Corporation, "Olabrite" is a registered trademark of the company), 0.1 part of polyoxyethylene ( Degree of polymerization: 20) 50 parts of glycol dioleic acid ester (Ionette DO-1000, Sanyo Kasei Kogyo Co., Ltd., “Ionet” is a registered trademark of the company) and glycerin monostearate (Rheidol MS-50, Kao) Co., Ltd., “Leodol” is a registered trademark of the same company.) 49.9 parts was stirred with a homogenizer (High Flex Disperser HG-92G, Taitec Co., Ltd.) at 4000 rpm, 150 ° C. for 3 hours, and then stirred. While cooling to 30 ° C., a comparative antifoaming agent (H1) was obtained.

  Using the antifoaming agents obtained in Examples 1 to 4 and Comparative Examples, emulsion paints were prepared by the following method, and these emulsion paints were evaluated for antifoaming properties and repellency by the following methods.

1. Preparation of Emulsion Base Coating Using the Excel Auto Homogenizer (Nippon Seiki Co., Ltd., Model ED) equipped with impeller type blades with the raw material composition shown in Table 1, it was ground and let down into a paint. The obtained paint was confirmed to have no particles of 5 microns or more by a dispersity test [JIS K5600-2-5: 1999 (corresponding to ISO 1524: 1983)].
Next, this paint was diluted with water to obtain 77 KU (25 ° C.) with a Stormer viscometer [JIS K5600-2-2: 1999 (corresponding to ISO 2431: 1993)] to obtain an emulsion base paint.

「タイペーク」、「ボンコート」、「テキサノール」は登録商標である。

“Taipeke”, “Boncoat” and “Texanol” are registered trademarks.

2. Preparation of emulsion paint To 100 parts of emulsion base paint, add 1 part of sample (ie antifoaming agent) and stir and mix with Excel Auto Homogenizer equipped with impeller blades at 15-25 ° C, 2000 rpm for 3 minutes. An emulsion paint was obtained.
Moreover, the emulsion paint for evaluation (blank) was obtained like the above except not adding a sample (namely, antifoamer).

<Evaluation 1 of defoaming property and repelling>
A tin plate (thickness 0.5 mm, 20 × 30 cm) was degreased with acetone / cloth, and then an emulsion coating for evaluation was applied with a roller so as to have a wet film thickness of 200 microns, and then 25 ° C. and 60% relative humidity. The film was dried in a control room adjusted for 1 day, and the surface of the coating film was observed.
The emulsion paint for evaluation was stored in an airtight container at 40 ° C. for one month (aging), and then stirred and mixed at 15 to 25 ° C. and 2000 rpm for 3 minutes with an Excel auto homogenizer equipped with impeller blades. Thus, an emulsion paint for aging evaluation was obtained, and the antifoaming property and repellency were similarly evaluated (after aging). The evaluation results are shown in Table 2.

Defoaming property: The number of bubble marks was visually confirmed. (A smaller value means higher defoaming properties and is preferable)
Repelling: The number of repelling or cratering marks was confirmed visually. (A smaller number means less repelling and is preferable)

  When the antifoaming agent of the present invention was used, excellent antifoaming properties were exhibited as compared with a coating using a comparative antifoaming agent. Moreover, there was little occurrence of repelling.

<Evaluation 2 of defoaming property>
To 100 parts of the emulsion base paint for evaluation, 0.5 part of a sample (that is, an antifoaming agent) is added, stirred using a desktop disper mill under conditions of 3,000 rpm × 5 minutes, and immediately evaluated with a specific gravity cup (50 mL). The specific gravity of the emulsion base paint was measured. An emulsion base paint for evaluation (blank) was prepared in the same manner as above except that the evaluation sample (antifoaming agent) was not mixed, and the specific gravity was measured. It means that defoaming performance is excellent, so that specific gravity is large. The evaluation results are shown in Table 3.

  When the antifoaming agent of the present invention was used, excellent antifoaming properties were exhibited as compared with a coating using a comparative antifoaming agent.

The antifoaming agent of the present invention is suitable for processing and wastewater treatment in fields such as the chemical industry, food industry, petroleum industry, textile industry, pulp and paper industry, civil engineering / architecture industry, and pharmaceutical industry.

Claims (2)

Higher fatty acid monoester of polyoxyethylene glycol (A), higher fatty acid diesters of polyoxyethylene glycol (B), a polyoxyalkylene monobutyl ether (C), a higher fatty acid (D), ethylene bis-stearyl amide (E) and a liquid at 25 ° C. base oil of the (F) only contains,
The polymerization degree of polyoxyethylene glycol is an integer of 13 to 40,
The higher fatty acid has 16 to 18 carbon atoms,
Polyoxyethylene glycol higher fatty acid monoester (A), polyoxyethylene glycol higher fatty acid diester (B), polyoxyalkylene monobutyl ether (C), higher fatty acid (D), ethylene bisstearyl amide (E) and 25 ° C. Based on the total weight of the liquid base oil (F), the content of the higher fatty acid monoester (A) of polyoxyethylene glycol is 2 to 12% by weight, the content of the higher fatty acid diester (B) of polyoxyethylene glycol 2 to 12% by weight, polyoxyalkylene monobutyl ether (C) content is 2 to 12% by weight, higher fatty acid (D) content is 0.3 to 2% by weight, ethylene bisstearylamide (E content of 1-6% by weight of), the content of the liquid base oil (F) at 25 ° C. is 60 to 88 wt% <br/> Anti-foaming agent characterized the door. The antifoaming agent according to claim 1, wherein the base oil (F) which is liquid at 25 ° C is a vegetable oil.