Antifoaming agents

Abstract

To provide a defoaming agent having excellent defoaming properties.SOLUTION: There is provided a defoaming agent which comprises: a hydrocarbon oil (A) having a paraffinic carbon content of 60 to 100 wt.%; at least one nucleating agent (B) selected from the group consisting of hydrophobic silica and wax; a mixed ester (C) having an esterification ratio of 50 to 99 mol% which comprises a polyoxyethylene glycol fatty acid diester and a polyoxyethylene glycol fatty acid monoester; and an ethylene oxide adduct of a hydroxyl group-containing triglyceride (D). Based on the weight of (A), (B), (C) and (D), it is preferable that the content of (A) is 60 to 99 wt.%, the content of (B) is 0.3 to 30 wt.%, the content of (C) is 0.1 to 15 wt.% and the content of (D) is 0.1 to 20 wt.%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an antifoaming agent. [Background technology]

[0002] Known examples of such antifoaming compositions include "an emulsion-type antifoaming composition obtained by emulsifying a composition of 5 to 35 parts by weight of an organic liquid, 0.5 to 5 parts by weight of a silicone oil, 0.5 to 5 parts by weight of hydrophobic silica, and 1 to 40 parts by weight of a modified silicone oil in water with an emulsifier" (Claim 1 of Patent Document 1), "the organic liquid is liquid paraffin oil produced by a complete hydrorefining method from a mineral oil, and has an iodine value of zero and a kinematic viscosity (40°C) of 12 to 70 cst" (Claim 2 of the same), and "the organic liquid is liquid paraffin oil produced by a complete hydrorefining method from a mineral oil, and has an iodine value of zero and a kinematic viscosity (40°C) of 12 to 70 cst, and is used in combination with a synthetic oil obtained by polymerizing propylene oxide or a mixture of propylene oxide and ethylene oxide with liquid paraffin oil, alcohols, and glycols" (Claim 4 of the same). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 6-39207 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventional emulsion-type antifoaming compositions have the problem of insufficient antifoaming properties. An object of the present invention is to provide a defoaming agent having excellent defoaming properties. [Means for solving the problem]

[0005] The antifoaming agent of the present invention is characterized by comprising: a hydrocarbon oil (A) having a paraffin carbon content of 60 to 100% by weight; at least one nucleating agent (B) selected from the group consisting of hydrophobic silica and wax; a mixed ester (C) consisting of a polyoxyethylene glycol fatty acid diester and a polyoxyethylene glycol fatty acid monoester, having an esterification rate of 50 to 99 mol%; The gist of the present invention is that it contains an ethylene oxide adduct (D) of a hydroxyl group-containing triglyceride. [Effects of the Invention]

[0006] The defoaming agent of the present invention has excellent defoaming properties. DETAILED DESCRIPTION OF THE INVENTION

[0007] Any hydrocarbon oil having a paraffin carbon content of 60 to 100 (preferably 65 to 80, more preferably 70 to 76) wt % can be used as the hydrocarbon oil (A) without any restrictions.

[0008] The paraffin carbon content (% by weight; hereinafter, this content will be abbreviated as %Cp) is measured in accordance with ASTM D 3238-22a (ndM ring analysis) and calculated as % by weight based on the total weight of paraffin carbon, naphthene carbon, and aromatic carbon contained in the hydrocarbon oil.

[0009] The kinematic viscosity (40°C; cSt) of the hydrocarbon oil (A) is preferably from 10 to 100, more preferably from 15 to 80, and particularly preferably from 24 to 66. Within this range, the defoaming property becomes even better.

[0010] Kinematic viscosity is measured in accordance with ASTM D445-21e2.

[0011] Examples of hydrocarbon oils (A) include hydrocarbon oils obtained by petroleum refining and refined mineral oils obtained by hydrogenating hydrocarbon oils. Among these, from a safety standpoint, those approved for use under regulations regarding food additives and food contact materials and suitable for use in applications involving direct or indirect contact with the human body are preferred (e.g., those that have passed the liquid paraffin test specified in the "Food Additives Standards" and / or the white mineral oil or technical white mineral oil test specified in "U.S. Food and Drug Administration (FDA) CFR Title 21"; or the white mineral oil (FCA0582) test specified in "9685-2016 (Hygiene Standard for Additives for Food Containers and Packaging Materials)" of the Chinese National Standard (GB Standard); the same applies below). Hydrocarbon oil (A) may be a mixture of multiple hydrocarbon oils, or may be a mixture of hydrocarbon oils with %Cp values ​​outside the above range, but the %Cp of such mixtures must be within the above range.

[0012] Hydrocarbon oils (A) are readily available on the market, and examples thereof include the MORESCO White series (MORESCO Corporation; "MORESCO-WHITE" is a registered trademark of the company), the COSMO SP series (Cosmo Oil Lubricants Co., Ltd.; "COSMO" is a registered trademark of Cosmo Energy Holdings Co., Ltd.), the YUBASE series (SK Lubricants Japan Co., Ltd.; "YUBASE" is a registered trademark of SK Enmove Company Limited), and the SK PHAZOL series (SK Lubricants Japan Co., Ltd.; "PHAZOL" is a registered trademark of SK Enmove Company Limited).

[0013] The content (wt %) of the hydrocarbon oil (A) based on the weight of the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C) and the ethylene oxide adduct of a hydroxyl group-containing triglyceride (D) is preferably 60 to 99, more preferably 65 to 95, and particularly preferably 70 to 90. Within this range, the defoaming property becomes even better.

[0014] The nucleating agent (B) can be at least one selected from the group consisting of hydrophobic silica and wax, and is not particularly limited. From the viewpoint of safety, the nucleating agent (B) is preferably one that is approved for use under regulations on food additives and food contact materials and that can be used in applications where it comes into direct or indirect contact with the human body.

[0015] The hydrophobic silica includes hydrophobic silica obtained by subjecting silica powder to hydrophobic treatment with a hydrophobizing agent.

[0016] From the viewpoint of safety, the silica powder and hydrophobizing agent are preferably those approved for use under regulations on food additives and food contact materials and suitable for use in applications where they come into direct or indirect contact with the human body. Examples of hydrophobizing agents include dimethylpolysiloxane and dichlorodimethylsilane.

[0017] The volume-based median diameter (d50; μm) of the hydrophobic silica is preferably from 0.1 to 20, more preferably from 1 to 10, and particularly preferably from 6 to 7. Within this range, the defoaming properties become even better.

[0018] The median diameter (d50) is determined as the 50% cumulative volume average particle diameter using a laser diffraction particle size analyzer conforming to JIS Z8825:2022 {for example, the Microtrac series manufactured by Leeds & Northrup or the Partica LA series manufactured by Horiba, Ltd.}, by adding a measurement sample to 1,000 parts by weight of 2-propanol {purity of 99% by weight or more} so that the measurement sample concentration is 0.1% by weight, measuring at a measurement temperature of 25±5°C, and then using 1.3749 as the refractive index of 2-propanol and a literature value ("A GUIDE FOR ENTERING MICROTRAC "RUN INFORMATION" (F3) DATA", prepared by Leeds & Northrup) as the refractive index of the measurement sample.

[0019] The M value (methanol wettability) of the hydrophobic silica is preferably from 40 to 80, more preferably from 45 to 75, and particularly preferably from 65 to 70. Within this range, the defoaming property becomes even better.

[0020] The M value (methanol wettability) is a characteristic value representing the degree of hydrophobic treatment on the powder surface. The higher the M value, the lower the hydrophilicity and the higher the proportion of hydrophobic treatment (higher hydrophobicity). It is represented by the volume ratio of the minimum amount of methanol required to uniformly disperse the powder (measured particles) in a water / methanol mixed solution and can be determined by the following method.

[0021] <Method for Measuring M Value> Prepare a water / methanol mixed solution with the methanol concentration varying at 5% volume intervals and put 5 ml of it into a test tube with a volume of 10 ml. Then add 0.2 g of the measurement sample, cover the test tube, invert it up and down 20 times, let it stand for 1 - 2 minutes, and then observe the content. Among the dispersion liquids without aggregates and with all of the measurement sample being wet and uniformly dispersed, take the methanol concentration (volume %) of the dispersion liquid with the lowest methanol concentration as the M value {It is a common practice not to specify the unit (volume %) of the M value.}.

[0022] As hydrophobic silica, it can be easily obtained on the market. For example, as product names, Nipsil SS series (Tokuyama Silica Corporation, "Nipsil" is a registered trademark of the company), AEROSIL series (Nippon Aerosil Co., Ltd., "AEROSIL" is a registered trademark of Evonik Operations GmbH), SIPERNAT series (Evonik Japan Co., Ltd., "SIPERNAT" is a registered trademark of Evonik Operations GmbH), CAB - O - SIL series (Cabot Corporation, "CAB - O - SIL" is a registered trademark of Cabot Corporation), REOLOSIL series (Tokuyama Corporation, "REOLOSIL" is a registered trademark of the company), and SYLOPHOBIC series (Fuji Silysia Chemical Ltd., "SYLOPHOBIC" is a registered trademark of the company), etc. can be mentioned.

[0023] Waxes include natural waxes and synthetic waxes.

[0024] Natural waxes include those produced in nature and those refined from them, such as vegetable waxes (carnauba wax, rice wax, etc.), animal waxes (beeswax, etc.), mineral waxes (montan wax, etc.), and petroleum waxes (paraffin wax, microcrystalline wax, etc.).

[0025] Synthetic waxes include those chemically synthesized, such as higher fatty acid amides, polyalkylene waxes, and polyalkylene oxide waxes.

[0026] Examples of higher fatty acid amides include reaction products of alkylenediamines having 1 to 6 carbon atoms with fatty acids having 10 to 22 carbon atoms (fatty acid diamides), and reaction products of alkylamines having 1 to 22 carbon atoms, alkenylamines having 4 to 22 carbon atoms, or ammonia with fatty acids having 10 to 22 carbon atoms (fatty acid monoamides).

[0027] Examples of fatty acid diamides include ethylene bisstearylamide, ethylene bispalmitylamide, ethylene bismyristylamide, ethylene bislaurylamide, ethylene bisoleylamide, propylene bisstearylamide, propylene bispalmitylamide, propylene bismyristylamide, propylene bislaurylamide, propylene bisoleylamide, butylene bisstearylamide, butylene bispalmitylamide, butylene bismyristylamide, butylene bislaurylamide, butylene bisoleylamide, methylene bislaurylamide, methylene bisstearylamide, and hexamethylene bisstearylamide.

[0028] Examples of fatty acid monoamides include N-stearylstearylamide, oleic acid amide, erucic acid amide, and stearylamide.

[0029] The polyalkylene waxes include (co)polymers of alkylene (ethylene and / or propylene, etc.), such as polyethylene wax and polypropylene wax.

[0030] The oxidized polyalkylene waxes include waxes obtained by oxidizing polyalkylene waxes by air oxidation and / or ozone oxidation, etc., to introduce carboxyl groups, hydroxyl groups, and / or formyl groups, etc., and examples thereof include low-density oxidized polyalkylene waxes, high-density oxidized polyalkylene waxes, and acid-modified polyalkylene waxes.

[0031] The acid value (mgKOH / g) of the oxidized polyalkylene wax is preferably from 6 to 20, more preferably from 8 to 18, and particularly preferably from 9 to 17. Within this range, the defoaming property becomes even better.

[0032] The acid value is measured in accordance with "5.4 Acid Value" of JIS K5902-1969.

[0033] The softening point (°C) of the wax is preferably 50 to 180, more preferably 80 to 143. The softening point is measured in accordance with JIS K2207-1996 (ring and ball method) and JIS K2207-2006 (Supplement 1).

[0034] Waxes are readily available on the market, and among natural waxes, vegetable waxes include the Carnauba Wax series (Toyochem Co., Ltd., Carnauba Wax) and the Rice Wax series (Yamakatsura Sangyo Co., Ltd., Rice Wax), animal waxes include beeswax (Miki Chemical Industry Co., Ltd., Beeswax), mineral waxes include Montan Wax (Yamakatsura Sangyo Co., Ltd., Montan Wax), and petroleum waxes include the Paraffin Wax series (Nihon Seimitsu Co., Ltd., Paraffin Wax) and the Hi-Mic series (Nihon Seimitsu Co., Ltd., Microcrystalline Wax).

[0035] Similarly, among synthetic waxes, examples of higher fatty acid amides include the Alflow series (NOF Corporation, higher fatty acid amides, "Alflow" is a registered trademark of the company) and the Fatty Acid Amide series (Kao Corporation, higher fatty acid amides). Examples of polyalkylene waxes include the Sunwax series (Sanyo Chemical Industries, Ltd., polyethylene wax) and the Viscol series (Sanyo Chemical Industries, Ltd., polypropylene wax). Examples of acid-modified polyalkylene waxes include the EPOLENE series (Westlake Longview Corporation, low-density oxidized polyethylene waxes (E-10, etc.), maleic acid-modified polypropylene waxes (E-43, etc.), etc., "EPOLENE" is a registered trademark of the company), the Umex series (Sanyo Chemical Industries, Ltd., maleic acid-modified polypropylene waxes (110TS, etc.), "Umex" is a registered trademark of the company), the Hiwax series (Mitsui Chemicals, Inc., high-density oxidized polyethylene waxes (E-4051, etc.), low-density oxidized polyethylene waxes (220MP, etc.), etc.), and the Licowax series (Clariant Chemicals AG, low-density oxidized polyethylene waxes (PED521, etc.), high-density oxidized polyethylene waxes (PED153, etc.), etc., "Licowax" is a registered trademark of Clariant AG).

[0036] The content (wt %) of the nucleating agent (B) is preferably 0.3 to 30, more preferably 1 to 25, and particularly preferably 3 to 20, based on the weight of the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C), and the ethylene oxide adduct of a hydroxyl group-containing triglyceride (D).

[0037] The mixed ester (C) may be any ester containing a polyoxyethylene glycol fatty acid diester and a polyoxyethylene glycol fatty acid monoester, and may have an esterification rate of 50 to 99 (preferably 65 to 99, and more preferably 70 to 97) mol %. From the viewpoint of safety, the mixed ester is preferably one that is approved for use under regulations on food additives and food contact materials and that can be used in applications where it comes into direct or indirect contact with the human body.

[0038] The esterification rate is as follows: 1 Calculated by H-NMR method. 30 mg of the mixed ester (C) was weighed into a 5 mm diameter NMR sample tube, and about 0.5 ml of a deuterated solvent (e.g., deuterated chloroform) was added to dissolve it. Then, about 0.1 ml of trifluoroacetic anhydride was added to prepare a sample for analysis. 1 Measure H-NMR.

[0039] Here, the unreacted hydroxyl groups contained in the mixed ester (C) react with trifluoroacetic anhydride to form trifluoroacetic esters, and a signal derived from a methylene group bonded to the oxygen atom of the esterified hydroxyl group is observed around 4.5 ppm, while a signal derived from a methylene group bonded to the oxygen atom of the hydroxyl group that has reacted with the fatty acid is observed around 4.2 ppm. Therefore, the esterification rate (mol %) is calculated using the following formula:

[0040] Esterification rate (mol%) = [b / (a+b)] × 100 In the formula, a is the integral of the signal derived from a methylene group bonded to an oxygen atom esterified with trifluoroacetic acid at around 4.5 ppm; and b is the integral of the signal derived from a methylene group bonded to an oxygen atom esterified with a fatty acid at around 4.2 ppm.

[0041] The number average molecular weight of polyoxyethylene glycol is preferably from 100 to 2000, more preferably from 150 to 1500, and particularly preferably from 200 to 1000. Within this range, the defoaming properties become even better.

[0042] The number average molecular weight can be determined from the hydroxyl value measured in accordance with JIS K1557-1:2007 (Method B).

[0043] Polyoxyethylene glycol can be obtained by known organic chemical synthesis methods, and is also commercially available (for example, PEG series, Sanyo Chemical Industries, Ltd.).

[0044] Fatty acids include saturated and unsaturated fatty acids having 12 to 30 carbon atoms. Saturated fatty acids include straight-chain saturated fatty acids (lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, cerotic acid, melissic acid, etc.) and branched-chain saturated fatty acids (isostearic acid, etc.).

[0045] Unsaturated fatty acids include straight-chain unsaturated fatty acids (such as myristoleic acid, palmitoleic acid, oleic acid, and triacontenoic acid) and branched-chain unsaturated fatty acids (such as isomyristoleic acid and isooleic acid).

[0046] Of these, from the viewpoint of antifoaming properties, straight-chain saturated fatty acids and straight-chain unsaturated fatty acids are preferred, more preferably lauric acid, myristic acid, palmitic acid, stearic acid, myristoleic acid, palmitoleic acid, 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, and most preferably lauric acid and oleic acid.

[0047] The polyoxyethylene glycol and fatty acid contained in the mixed ester (C) may be a single component, or may contain multiple types of fatty acids.

[0048] The mixed ester (C) may contain unreacted polyoxyethylene glycol and / or unreacted fatty acid. The amount of unreacted polyoxyethylene glycol is statistically calculated from the esterification rate, and this amount (wt%) is preferably 0 to 11 based on the weight of the mixed ester (C). The amount of unreacted fatty acid is calculated from the acid value measured in accordance with "3.1 Neutralization titration" of JIS K0070-1992, and this amount (wt%) is preferably 0 to 10 based on the weight of the mixed ester (C).

[0049] The mixed ester (C) can be easily prepared by a known esterification reaction.

[0050] The content (wt %) of the mixed ester (C) is preferably 0.1 to 15, more preferably 0.5 to 12, and particularly preferably 1 to 10, based on the weight of the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C), and the ethylene oxide adduct of a hydroxyl group-containing triglyceride (D).

[0051] The ethylene oxide adduct (D) of a hydroxyl-containing triglyceride can be any adduct obtained by an addition reaction between a hydroxyl-containing triglyceride and ethylene oxide without any limitations. From the viewpoint of safety, the ethylene oxide adduct (D) of a hydroxyl-containing triglyceride is preferably one that is approved for use under regulations on food additives and food contact materials and that can be used in applications that come into direct or indirect contact with the human body.

[0052] Hydroxylated triglycerides include triesters of glycerin and a fatty acid containing at least one hydroxylated fatty acid.

[0053] Examples of fatty acids containing a hydroxyl group include 12-hydroxystearic acid, ricinoleic acid, savinic acid, 2-hydroxytetradecanoic acid, isopureic acid, 2-hydroxyhexadecanoic acid, jalapinolic acid, uniperinic acid, ambrettolic acid, aleuritic acid, 2-hydroxystearic acid, 18-hydroxyoctadecanoic acid, 9,10-dihydroxystearic acid, camrolenoic acid, ferronic acid, cerebronic acid, 9-hydroxystearic acid, and 10-hydroxystearic acid, among which 12-hydroxystearic acid is preferred.

[0054] Examples of hydroxyl group-containing triglycerides include castor oil and hydrogenated castor oil.

[0055] The number of moles of ethylene oxide added per mole of the hydroxyl group-containing triglyceride is preferably from 1 to 40, more preferably from 3 to 30, and particularly preferably from 6 to 25. Within this range, the defoaming properties become even better.

[0056] The ethylene oxide adduct of a hydroxyl group-containing triglyceride (D) can be obtained by known organic chemical synthesis methods, or can be easily obtained from the market, and examples thereof include the BRAWNON BR series, CW series, and RCW series (Aoki Oil & Fats Co., Ltd., "BRAWNON" is a registered trademark of the company), the PELLETEX CO series (Miyoshi Oil & Fats Co., Ltd., "PELLETEX" is a registered trademark of the company), and the NIKKOL HCO series (Nikko Chemicals Co., Ltd., "NIKKOL" is a registered trademark of the company).

[0057] The content (wt %) of the ethylene oxide adduct of a hydroxyl-containing triglyceride (D) based on the weight of the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C) and the ethylene oxide adduct of a hydroxyl-containing triglyceride (D) is preferably 0.1 to 20, more preferably 0.3 to 17, and particularly preferably 0.5 to 15. Within this range, the defoaming property becomes even better.

[0058] The antifoaming agent of the present invention may further contain a polyoxyalkylene glycol (E) containing 0 to 50 mol % of oxyethylene units and 50 to 100 mol % of oxypropylene units and / or oxybutylene units; and / or a silicone (F). From the viewpoint of safety, the polyoxyalkylene glycol (E) and the silicone (F) are preferably those approved for use under regulations on food additives and food contact materials and suitable for use in applications where they come into direct or indirect contact with the human body.

[0059] The content (mol %) of oxyethylene units contained in the polyoxyalkylene glycol (E) relative to the total number of moles of oxyethylene units, oxypropylene units, and oxybutylene units is preferably 0 to 50, more preferably 0 to 41. The content (mol %) of oxypropylene units and / or oxybutylene units relative to the total number of moles of oxyethylene units, oxypropylene units, and oxybutylene units is preferably 50 to 100, more preferably 59 to 100.

[0060] Examples of the polyoxyalkylene glycol (E) include polyoxypropylene glycol, polyoxybutylene glycol, polyoxyethylene-polyoxypropylene glycol, polyoxyethylene-polyoxybutylene glycol, etc. Among these, polyoxypropylene glycol and block-type polyoxyethylene-polyoxypropylene glycol are preferred.

[0061] The polyoxyalkylene glycol (E) can be easily prepared by a known alkylene oxide addition reaction and is readily available on the market. Examples include the Sannix PP series (Sanyo Chemical Industries, Ltd., "Sanyx" is a registered trademark of the company), the Newpol PE series (Sanyo Chemical Industries, Ltd., "Newpol" is a registered trademark of the company), and the Uniol D series (NOF Corporation, "Uniol" is a registered trademark of the company).

[0062] When polyoxyalkylene glycol (E) is contained, the content (wt %) of polyoxyalkylene glycol (E) based on the weight of the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C) and the ethylene oxide adduct of a hydroxyl group-containing triglyceride (D) is preferably 20 to 500, more preferably 50 to 300, and particularly preferably 75 to 210. Within this range, good defoaming properties are obtained.

[0063] As the silicone (F), dimethyl silicone oil, modified silicone oil, etc. can be used. Dimethyl silicone oil includes dimethyl silicone oil having a kinematic viscosity of 5 to 10,000 (cSt, 25°C). Modified silicone oil includes dimethyl silicone oil in which some of the methyl groups have been replaced with an alkoxypolyoxyalkyleneoxypropyl group (alkoxy having 1 to 6 carbon atoms, alkylene having 2 to 3 carbon atoms, degree of polymerization 2 to 50), an alkoxypolyoxyalkylene group (alkoxy having 1 to 6 carbon atoms, alkylene having 2 to 3 carbon atoms, degree of polymerization 2 to 50), etc.

[0064] Silicones (F) are readily available on the market, and examples thereof include the XIAMETER series (Dow Corning Toray Co., Ltd., "XIAMETER" is a registered trademark of Dow Corning Corporation), the FS Antifoam series (Dow Corning Toray Co., Ltd., "Antifoam" is a registered trademark of Kao Corporation), the SH200 series (Dow Corning Toray Co., Ltd.), the DK Q1 series (Dow Corning Toray Co., Ltd.), the KS series (Shin-Etsu Chemical Co., Ltd.), the SILFOAM series (Wacker Asahi Kasei Silicones Co., Ltd., "SILFOAM" is a registered trademark of Wacker Chemie AG), and the PULPSIL series (Wacker Asahi Kasei Silicones Co., Ltd., "PULPSIL" is a registered trademark of Wacker Chemie Aktiengesellschaft).

[0065] When silicone (F) is contained, the content (wt %) of silicone (F) based on the weight of the hydrocarbon oil (A), nucleating agent (B), mixed ester (C) and ethylene oxide adduct of hydroxyl group-containing triglyceride (D) is preferably 0.1 to 10, more preferably 0.3 to 5, and particularly preferably 0.5 to 3. Within this range, the defoaming properties are further improved.

[0066] The antifoaming agent of the present invention may be produced by any method that can uniformly mix the hydrocarbon oil (A), the nucleating agent (B), the mixed ester (C), the ethylene oxide adduct of a hydroxyl group-containing triglyceride (D), and, if necessary, the polyoxyalkylene glycol (E) and / or the silicone (F), and any known mixing method can be used.

[0067] The defoaming agent of the present invention is effective against aqueous foaming liquids, but from the viewpoint of safety, its use is permitted under regulations on food additives and food contact materials, and it is preferably applicable to applications in which it comes into direct or indirect contact with the human body. For example, it is suitable for aqueous coating materials for food packaging and aqueous glue materials for clothing (aqueous foaming liquids applied to members that come into contact with food or the human body). [Example]

[0068] Unless otherwise specified, all parts below mean parts by weight. <Production Example 1> One mole of polyoxyethylene glycol (PEG, number-average molecular weight Mn 600, PEG-600, Sanyo Chemical Industries, Ltd.) and two moles of oleic acid (molecular weight 282) were subjected to a dehydration reaction at 130°C for 5 hours in the presence of 0.01 mole of paratoluenesulfonic acid to prepare a mixed ester (c1) consisting of a PEG (Mn 600) oleate diester and a PEG (Mn 600) oleate monoester. 1 The esterification rate of the mixed ester (c1) was determined using H-NMR spectrum analysis (hereinafter the same), and was found to be 95 mol %.

[0069] <Production Example 2> A mixed ester (c2) consisting of a PEG (Mn600) oleic acid diester and a PEG (Mn600) oleic acid monoester was obtained in the same manner as in Production Example 1, except that "2 mol parts of oleic acid" was changed to "1.47 mol parts of oleic acid." The esterification rate was 70 mol%.

[0070] <Production Example 3> A mixed ester (c3) of oleic acid diester of PEG (Mn400) and oleic acid monoester of PEG (Mn400) was obtained in the same manner as in Production Example 1, except that "2 mole parts of oleic acid" was changed to "1.45 mole parts of oleic acid" and "polyoxyethylene glycol (Mn600)" was changed to "polyoxyethylene glycol (PEG, number average molecular weight Mn400, PEG-400, Sanyo Chemical Industries, Ltd.)". The esterification rate was 70 mole %.

[0071] <Production Example 4> A mixed ester (c4) of lauric acid diester of PEG (Mn200) and lauric acid monoester of PEG (Mn200) was obtained in the same manner as in Production Example 1, except that "2 parts by mole of oleic acid" was changed to "2 parts by mole of lauric acid" and "polyoxyethylene glycol (Mn600)" was changed to "polyoxyethylene glycol (PEG, number average molecular weight Mn200, PEG-200, Sanyo Chemical Industries, Ltd.)". The esterification rate was 97 mol%.

[0072] <Production Example 5> A mixed ester (c5) of oleic acid diester of PEG (Mn 1000) and oleic acid monoester of PEG (Mn 1000) was obtained in the same manner as in Production Example 1, except that "polyoxyethylene glycol (Mn 600)" was changed to "polyoxyethylene glycol (PEG, number average molecular weight Mn 1000, PEG-1000, Sanyo Chemical Industries, Ltd.)". The esterification reaction rate was 94%.

[0073] Example 1 A defoaming agent (1) of the present invention was prepared by uniformly mixing 75 parts of a hydrocarbon oil (a1: Moresco White P-350P, MORESCO Corporation, kinematic viscosity 66 cSt (40°C), %Cp 70 wt%); 15 parts of a nucleating agent (b1: NIPSIL SS-215, Tosoh Silica Corporation, hydrophobic silica, M value 65, volume-based median diameter 6 μm); 3 parts of a mixed ester (c1); 7 parts of an ethylene oxide adduct (d1: 10-mol ethylene oxide adduct of castor oil, BRAWNON BR-410, Aoki Oil & Fat Co., Ltd.); and 75 parts of a polyoxyalkylene glycol (e1: polypropylene glycol having a number-average molecular weight of 1,000, SANNICS PP-1000, Sanyo Chemical Industries, Ltd.).

[0074] <Example 2> A defoaming agent (2) of the present invention was prepared by uniformly mixing 85 parts of a hydrocarbon oil (a1), 9 parts of a nucleating agent (b2: SIPERNAT D10, Evonik Japan, hydrophobic silica, M value 70, volume-based median diameter 7 μm), 3 parts of a mixed ester (c2), and 3 parts of an ethylene oxide adduct (d2: ethylene oxide 6 mol adduct of castor oil, BRAWNON BR-406, Aoki Oil & Fat Co., Ltd.).

[0075] Example 3 A defoaming agent (3) of the present invention was prepared by uniformly mixing 90 parts of a hydrocarbon oil (a2: Moresco White P-120, MORESCO Corporation, kinematic viscosity 24 cSt (40°C), %Cp 70% by weight); 3 parts of a nucleating agent (b1); 3 parts of a mixed ester (c3); and 4 parts of an ethylene oxide adduct (d3, an ethylene oxide 3-mol adduct of hydrogenated castor oil, BRAWNON CW-3, Aoki Oil & Fat Co., Ltd.).

[0076] Example 4 70 parts of hydrocarbon oil (a3: YUBASE8, SK Lubricants Japan Co., Ltd., kinematic viscosity 47 cSt (40°C), %Cp 76% by weight); 14 parts of nucleating agent (b1); 1 part of mixed ester (c4); 15 parts of ethylene oxide adduct (d1); 70 parts of polyoxyalkylene glycol (e2: polypropylene glycol having a number average molecular weight of 2000, Sannix PP-2000, Sanyo Chemical Industries, Ltd.); 70 parts of polyoxyalkylene glycol (e3: Pluronic-type block adduct of 4 moles of ethylene oxide and 31 moles of propylene oxide, Newpol PE-61, Sanyo Chemical Industries, Ltd.); 70 parts of polyoxyalkylene glycol (e4: Pluronic-type block adduct of 24 moles of ethylene oxide and 35 moles of propylene oxide, Newpol PE-74, Sanyo Chemical Industries, Ltd.); and silicone (f1: modified silicone, XIAMETER ACP-1500 (Toray Dow Corning Co., Ltd.) and 0.5 parts were uniformly mixed to prepare the antifoaming agent (4) of the present invention.

[0077] <Example 5> A defoaming agent (5) of the present invention was prepared by uniformly mixing 70 parts of a hydrocarbon oil (a2), 19.5 parts of a nucleating agent (b1), 5 parts of a mixed ester (c3), 5 parts of an ester mixture (c4), 0.5 parts of an ethylene oxide adduct (d1), 70 parts of a polyoxyalkylene glycol (e2), 70 parts of a polyoxyalkylene glycol (e3), 70 parts of a polyoxyalkylene glycol (e4), and 3 parts of a silicone (f1).

[0078] Example 6 30 parts of hydrocarbon oil (a1) and 5 parts of nucleating agent (b3: Epolene E-10, Eastman Chemical, oxidized polyethylene wax, acid value 17 mg KOH / g, softening point 104°C) were heated and stirred to 145°C, and heating and stirring were continued at this temperature for an additional 15 minutes to obtain a nucleating agent solution (1).

[0079] Next, 58 parts of hydrocarbon oil (a1), 3 parts of mixed ester (c5), 3 parts of ethylene oxide adduct (d1), and 1 part of ethylene oxide adduct (d2) were stirred, and the nucleating agent solution (1) was added thereto, followed by cooling to 25°C and stirring to obtain dispersion (1).

[0080] Dispersion (1) was homogenized at 3500 psi (24.1 MPa) using a Gaulin homogenizer (manufactured by Manton Gaulin) to obtain a defoaming agent (6) of the present invention.

[0081] Example 7 30 parts of hydrocarbon oil (a1) and 5 parts of nucleating agent (b4: Alflow H-50S, NOF Corporation, ethylene bisstearylamide, softening point 143°C) were heated and stirred to 145°C, and heating and stirring were continued at this temperature for an additional 15 minutes to obtain a nucleating agent solution (2).

[0082] Next, 58 parts of hydrocarbon oil (a1), 6 parts of mixed ester (c2), and 1 part of ethylene oxide adduct (d4: 25 moles of ethylene oxide adduct of castor oil, BRAWNON BR-425, Aoki Oil & Fat Co., Ltd.) were cooled and stirred, and the nucleating agent solution (2) was added thereto, followed by cooling to 25°C and stirring to obtain dispersion (2).

[0083] Dispersion (2) was homogenized at 3500 psi (24.1 MPa) using a Gaulin homogenizer (manufactured by Manton Gaulin) to obtain a defoaming agent (7) of the present invention.

[0084] Example 8 30 parts of hydrocarbon oil (a1) and 5 parts of nucleating agent (b4: Hi-Mic-1070, Nippon Seiro, microcrystalline wax, softening point 80°C) were heated and stirred to 145°C, and heating and stirring were continued at this temperature for an additional 15 minutes to obtain a nucleating agent solution (3).

[0085] Next, 58 parts of hydrocarbon oil (a1), 3 parts of mixed ester (c5), 3 parts of ethylene oxide adduct (d1), and 1 part of ethylene oxide adduct (d2) were stirred, and the nucleating agent solution (3) was added thereto, followed by cooling to 25°C and stirring to obtain dispersion (3).

[0086] Dispersion (3) was homogenized at 3500 psi (24.1 MPa) using a Gaulin homogenizer (manufactured by Manton Gaulin) to obtain a defoaming agent (8) of the present invention.

[0087] <Comparative Example> Using available raw materials, a comparative defoamer similar to the emulsion composition prepared in Production Example 1 described in Patent Document 1 was prepared as follows. That is, 30 parts of hydrocarbon oil (a2) were added with stirring to 100°C with 1 part of silicone oil (Silicone Oil KF-96-20cS, Shin-Etsu Chemical Co., Ltd.) and 3 parts of nucleating agent (b1), and the mixture was heated to a temperature of 100°C and dispersed. Next, 1 part of a nonylphenol ethylene oxide 6-mol adduct (Brawnon N-506, Aoki Oil & Fat Co., Ltd.), 1 part of sorbitan oleate (Ionet S-80, Sanyo Chemical Industries, Ltd.; "Ionet" is a registered trademark of the company), and 3 parts of polyether-modified silicone oil (Antifoam FS-80, Dow Corning) were added, and the resulting dispersion was emulsified and dispersed in 61 parts of water at 60°C to obtain a comparative emulsion defoamer (h).

[0088] <Evaluation of anti-foaming properties> After stirring and mixing 90 g of acrylic styrene resin emulsion (BASF, ACRONAL 295DN) and 10 g of ion-exchanged water, this stirred mixture and each antifoaming agent (30 μL for any of Examples 1 to 7 or 77 μL for Comparative Example) were stirred for 5 minutes using a stand automixer DL-7524 (Kai Corporation, speed adjustment lever 10). After stirring, the liquid was transferred to a 300 mL graduated cylinder, and the weight (g) and volume (ml) were measured after 8 seconds, and the specific gravity was calculated and shown in the table below. A higher specific gravity indicates higher antifoaming properties and is preferable. Furthermore, the specific gravity (blank) was calculated in the same manner as above, except that no antifoaming agent was added, and shown in the table below.

[0089] <Evaluation of water dispersibility> (1) Initial water dispersibility 5g of each antifoaming agent and 95g of ion-exchanged water were mixed in a 100mL beaker at 25°C for 5 minutes using a magnetic stirrer (rotation speed: 400 rpm). After stopping the stirring, the mixture was left to stand at 25°C for 15 minutes, and then evaluated according to the following criteria, as shown in the table below. A rating of ○ indicates high dispersibility and is preferred.

[0090] ○: remained uniformly dispersed ×: Oil droplets and oil film were observed

[0091] (2) Stability over time 180 g of each antifoaming agent was placed in a 220 mL glass container, sealed, and stored at 40°C for one month. After that, each antifoaming agent was mixed in a stirring / defoaming device (Mazerustar KK-VT300, Kurabo Industries, Ltd.) at 25°C, revolution 737 rpm, rotation 1340 rpm for one minute, and water dispersibility was evaluated in the same manner as above. The results are shown in the table below according to the following criteria. A ○ indicates excellent stability over time, which is preferable.

[0092] ○: remained uniformly dispersed ×: Oil droplets and oil film were observed

[0093] [Table 1]

[0094] As described above, the defoaming agent of the present invention was superior in defoaming properties and stability over time compared to the comparative defoaming agent.

Claims

1. A hydrocarbon oil (A) having a paraffin carbon content of 60 to 100% by weight; at least one nucleating agent (B) selected from the group consisting of hydrophobic silica and wax; a mixed ester (C) consisting of a polyoxyethylene glycol fatty acid diester and a polyoxyethylene glycol fatty acid monoester, having an esterification rate of 50 to 99 mol%; and an ethylene oxide adduct of a hydroxyl group-containing triglyceride (D).

2. 2. The defoaming agent according to claim 1, wherein the content of the hydrocarbon oil (A) is 60 to 99% by weight; the content of the nucleating agent (B) is 0.3 to 30% by weight; the content of the mixed ester (C) is 0.1 to 15% by weight; and the content of the ethylene oxide adduct (D) is 0.1 to 20% by weight, based on the weights of the hydrocarbon oil (A); the nucleating agent (B); the mixed ester (C); and the ethylene oxide adduct (D).

3. 3. The defoaming agent according to claim 1, wherein the hydrocarbon oil (A) has a kinematic viscosity at 40°C of 10 to 100 cSt.

4. 3. The defoaming agent according to claim 1 or 2, further comprising: a polyoxyalkylene glycol (E) containing 0 to 50 mol % of oxyethylene units and 50 to 100 mol % of oxypropylene units and / or oxybutylene units; and / or a silicone (F).

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