JP2022045586A - Defoamant - Google Patents

Abstract

To provide a defoamant excellent in the finish appearance of a coating film.SOLUTION: A defoamant characterized in containing silicone (A) having a weight average molecular weight of 200,000-1,000,000 and diol branch carboxylic acid ester (B1) or dicarboxylic acid branch alkyl ester (B2) is used. It is desirable that diol branch carboxylic acid ester (B1) or dicarboxylic acid branch alkyl ester (B2) is at least one kind selected from the group consisting of 2,2,4-trimethyl-1,3-pentane diol 2-methyl propanoic acid monoester (b11), 2,2,4-trimethyl-1,3-pentane diol 2-methyl propanoic acid diester (b12) and hexane dicarboxylic acid diisobutyl (b21).SELECTED DRAWING: None

Description

The present invention relates to an antifoaming agent. More specifically, the present invention relates to a defoaming agent suitable for a non-aqueous coating composition.

［式中、Ｒｆはフルオロアルキル基、Ｒ１は炭素数１～６のアルキル基またはフェニル基であり、これらは同一でも異なっていてもよく、Ｒ２は炭素数１～６の炭化水素基、ＯＨ基またはアルコキシ基である。ｍは１～２００００の整数を、ｎは１～１０００の整数を示す。］で表される化合物と下記一般式（２）

［式中、Ｒ３は炭素数１～４のアルキル基であり、Ｒ４は炭素数１２～２４の炭化水素基である。］で表されるアクリル酸アルキルエステル単量体の単独あるいはその２種以上を重合（共重合）して得られる平均分子量１００００～２０００００の重合体とからなる非水系樹脂分散型塗料用消泡剤が知られている（特許文献１）。 As a defoaming agent for non-aqueous coating compositions, the following general formula (1)

[In the formula, Rf is a fluoroalkyl group, R1 is an alkyl group or a phenyl group having 1 to 6 carbon atoms, and these may be the same or different, and R2 is a hydrocarbon group having 1 to 6 carbon atoms and an OH group. Or it is an alkoxy group. m represents an integer of 1 to 20000, and n represents an integer of 1 to 1000. ] And the following general formula (2)

[In the formula, R3 is an alkyl group having 1 to 4 carbon atoms, and R4 is a hydrocarbon group having 12 to 24 carbon atoms. ], A defoaming agent for non-aqueous resin-dispersed paints, which is a polymer having an average molecular weight of 10,000 to 200,000 obtained by polymerizing (copolymerizing) the acrylic acid alkyl ester monomer alone or two or more thereof. Is known (Patent Document 1).

JP-A-2002-301306

The conventional defoaming agent has a problem that the finished appearance of the coating film (crater generation, etc.) is inferior.
An object of the present invention is to provide an antifoaming agent having an excellent finished appearance of a coating film.

The defoaming agent of the present invention is characterized by containing a silicone (A) having a weight average molecular weight of 200,000 to 1,000,000 and a branched carboxylic acid ester (B1) of a diol or a branched alkyl ester (B2) of a dicarboxylic acid. The point is the gist.

The gist of the non-aqueous coating composition of the present invention is that it contains the above-mentioned defoaming agent.

The defoaming agent of the present invention is excellent in the finished appearance of the coating film.

Since the non-aqueous coating composition of the present invention contains the above-mentioned defoaming agent, the finished appearance of the coating film is excellent.

Examples of the silicone (A) having a weight average molecular weight (Mw) of 200,000 to 1,000,000 (preferably 300,000 to 800,000, more preferably 350,000 to 750,000) include polydimethylsiloxane (a1), α, ω-. Dihydroxy-polydimethylsiloxane (a2) and α-aminopropylpolydimethylsiloxane (a3) are included.

The weight average molecular weight (Mw) is measured by gel permeation chromatography (GPC) using polystyrene having a known molecular weight as a standard substance.

Silicone (A) is readily available on the market, and polydimethylsiloxane (a1) includes KF-9008, KF-9011, KF-9013, KF-9014, KF-9028, KF-9030, MK-15H, X. -21-5495, KF-9028, KF-9030, X-21-5613, X-21-5666, X-21-5847 and X-21-5894 (above, Shin-Etsu Chemical Co., Ltd.); SH200-1, 000000cs, BY16-140, BY11-003, BY11-007, BY11-014, BY11-026, BY11-040, BY22-019, BY22-020, BY22-034, BY22-055, BY22-060 and BY25- 320 (above, Toray Dow Corning Co., Ltd.) and the like can be mentioned.

As α, ω-dihydroxy-polydimethylsiloxane (a2), X-21-5613, X-21-5666 (above, Shin-Etsu Chemical Co., Ltd.); 1501 Fluid, 1503 Fluid and CB-1556 Fluid (above, Toray Dow Corning). Co., Ltd.) and the like.

Examples of the α-aminopropylpolydimethylsiloxane (a3) include KF-8017, KF-8018 and KF-8020 (Shin-Etsu Chemical Co., Ltd.).

Among the silicones (A), polydimethylsiloxane (a1), α, ω-dihydroxy-dimethylsiloxane (a2) and a mixture thereof are preferable, and polydimethylsiloxane (a1) is more preferable.

The branched carboxylic acid ester (B1) of the diol includes a diol having 2 to 8 carbon atoms, a branched carboxylic acid having 3 to 30 carbon atoms and a monoester or a diester, and contains an ethanediol isopropanoic acid ester and a propanediol isobutanoic acid ester. , Butanediol 2,2-dimethylpropionic acid ester, pentandiol isopentanoic acid ester, pentandiol isobutanoic acid ester, hexanediol 2,2-dimethylpropionic acid ester, ethanediol isohexanoic acid ester, propanediol isohexanoic acid ester, butane Diol 2-ethylhexanoic acid ester, pentandiol isotridecanoic acid ester, hexanediol isotetradecanoic acid ester, propanediol isooctadecanoic acid ester, butanediol 2-ethylhexanoic acid ester, pentanediol 2-propylheptanic acid ester, hexanediol 2-Butyl octanoic acid ester, propanediol 2-hexyldecanoic acid ester, butanediol 2-octyldodecanoic acid ester, pentanediol 2-decyltetradecanoic acid ester, hexanediol 2-dodecylhexanoic acid ester, ethanediol 3,5,5- Trimethylhexanoic acid ester, propanediol 3,7,1,1-trimethyldodecanoic acid ester, ethanediol isotoriacontanoic acid ester, 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid ester and the like Can be mentioned.

The branched alkyl ester (B2) of the dicarboxylic acid includes a monoester or a diester of a dicarboxylic acid having 4 to 8 carbon atoms and a branched alkanol having 3 to 30 carbon atoms, and includes isopropyl ethanedicarboxylate, isobutyl propanodicarboxylate, and butane. T-butyl dicarboxylate, isopentyl pentandicarboxylate, isobutyl hexanedicarboxylate, neopentyl hexanedicarboxylate, isohexyl ethanedicarboxylate, 2-ethylhexyl propandicarboxylate, isotridecyl butanedicarboxylate, isotetradecylpentanedicarboxylate, isooctadecyl hexanedicarboxylate , Ethandicarboxylic acid isotoria concil, propanedicarboxylic acid 2-ethylhexyl, butanedicarboxylic acid 2-propylheptyl, pentandicarboxylic acid 2-butyloctyl, hexanedicarboxylic acid 2-hexyldecyl, ethanedicarboxylic acid 2-octyldodecyl, propanedicarboxylic acid Examples include 2-decyltetradecyl acid, 2-dodecylhexyl butanedicarboxylic acid, 2-dodecylhexadecyl pentanedicarboxylic acid, 3,5,5-trimethylhexyl hexanedicarboxylic acid and 3,7,11-trimethyldodecyl ethanedicarboxylic acid. Be done.

Examples of the branched carboxylic acid ester (B1) of the diol or the branched alkyl ester (B2) of the dicarboxylic acid include 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid monoester (b11), 2,2. , 4-trimethyl-1,3-pentanediol 2-methylpropanoic acid diester (b12), diisobutyl hexanedicarboxylic acid (b21) or mixtures thereof are preferably included.

The content (% by weight) of the silicone (A) is 0.1 to 99 based on the total weight of the silicone (A) and the branched carboxylic acid ester (B1) of the diol or the branched alkyl ester (B2) of the dicarboxylic acid. Is preferable, more preferably 1 to 50, and particularly preferably 2 to 10. The content (% by weight) of the branched carboxylic acid ester (B1) of the diol or the branched alkyl ester (B2) of the dicarboxylic acid is the branched alkyl of the branched carboxylic acid ester (B1) or the dicarboxylic acid of the silicone (A) and the diol. Based on the total weight with the ester (B2), it is preferably 1 to 99.9, more preferably 50 to 99, and particularly preferably 90 to 98. Within this range, the defoaming property and the appearance of the coating film are further improved.

The defoaming agent of the present invention contains a defoaming component (C) other than silicone (A), a branched carboxylic acid ester of a diol (B1) and a branched alkyl ester of a dicarboxylic acid (B2), as long as the effects of the present invention are not impaired. May be contained.

The defoaming component (C) includes a fluorine-modified silicone (C1), a liquid polymer (C2), an oil-soluble polymer (C3), a silicone (C4) and hydrophobic silica (C5).

The fluorine-modified silicone (C1) includes a silicone containing an organosiloxane unit (α) represented by the formula (1).

Rf represents a fluoroalkyl group, R represents an alkyl group having 1 to 6 carbon atoms, Si represents a silicon atom, and O represents an oxygen atom.

As the fluoroalkyl group (Rf), a fluoroalkyl group having 1 to 8 carbon atoms or the like can be used, and 1,1,1-trifluoromethyl, 3,3,3-trifluoropropyl, 4,4,4,3 , 3-Pentafluoro-1-butyl, 6,6,6,5,5,4,3,3-nonafluoro-1-hexyl and 8,8,8,7,7,6,6,5 5,4,4,3,3-tridecafluoro-1-octyl and the like can be mentioned. Of these, 6,6,6,5,5,4,4,3,3-nonafluoro-1-hexyl is preferable from the viewpoint of defoaming performance.

Examples of the alkyl group (R) having 1 to 6 carbon atoms include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, 2-ethylhexyl and the like. Of these, methyl is preferable from the viewpoint of defoaming performance.

The fluorine-modified silicone (C1) may contain an organosiloxane unit (β) other than the organosiloxane unit (α).
Other organosiloxane units (β) include dimethylsiloxane units, methylhydrogensiloxane units, methylphenylsiloxane units and diphenylsiloxane units. Of these, the dimethylsiloxane unit is preferable from the viewpoint of defoaming performance.

When the fluoromodified silicone (C1) is composed of an organosiloxane unit (α) and another organosiloxane unit (β), the content (mol%) of the organosiloxane unit (α) represented by the formula (1) is , 10 to 80 is preferable, more preferably 20 to 78, and particularly preferably 30 to 75, based on the number of moles of all the organosiloxane units constituting the fluorine-modified silicone (C1). Further, in this case, the content (mol%) of the other organosiloxane unit (β) is preferably 20 to 90, more preferably 20 to 90, based on the number of moles of all the organosiloxane units constituting the fluoromodified silicone (C1). Is 22 to 80, particularly preferably 25 to 70. Within these ranges, the defoaming performance and the finished appearance of the coating film are further improved.

The fluorinated silicone (C1) can be produced by a known method (for example, Japanese Patent Application Laid-Open No. 59-130894) and can be easily obtained from the market. Products available from the market include FL100, FA-600, FA-630, X-22-821, X-22-822 (Shin-Etsu Chemical Co., Ltd.); FS-1265 (Toray Dow Corning Co., Ltd.), etc. Can be mentioned.

The liquid of the liquid polymer (C2) has a viscosity {the viscosity of itself (neat viscosity)} measured by a Brookfield type rotary viscometer based on JIS K7117-1: 1999 of 1,000 Pa · s (25 ° C.). It means that it is as follows.

The viscosity of the liquid polymer (C2) (JIS K7117-1: 1999, 25 ° C., Pa · s, neat viscosity) is preferably 0.3 to 100, more preferably 0.6 to 95, and particularly preferably 0. It is 0.7 to 90.

The liquid polymer (C2) is not particularly limited as long as it is liquid, and examples thereof include polyα-olefin (C21), polydiene (C22), and a mixture thereof.

The poly-α-olefin (C21) is not particularly limited as long as it is composed of an α-olefin and is a liquid (co) polymer.

As the α-olefin, ethylene, propylene, 1-butene, 1-hexene, 1-octene and the like can be used. Of these, ethylene, propylene and 1-butene are preferable, and ethylene and propylene are more preferable.

Of the poly-α-olefins (C21), ethylene-α-olefin copolymers and polypropylene are preferable, and ethylene-propylene copolymers are more preferable, from the viewpoint of the finished appearance of the coating film.

Poly-α-olefins (C21) are readily available on the market and are available in the Lucant® series {HC-40 (830 mPa · s), HC-100 (2.6 Pa · s), HC-600 (27 Pa · s), HC-1100 (50 Pa · s), HC-2000 (95 Pa · s)} and the like (Mitsui Chemicals, Inc.) can be mentioned. The values in parentheses are the viscosities measured at 25 ° C. using a Brookfield type rotary viscometer conforming to JIS K7117-1: 1999.

The polydiene (C22) is not limited as long as it is a liquid polydiene, but polybutadiene and a butadiene copolymer are preferable, and polybutadiene is particularly preferable.

Examples of the copolymerized monomer of the butadiene copolymer include acrylonitrile and styrene.

Examples of the polydiene (C22) are easily available from the market, and examples thereof include POLYVEST (registered trademark) 110 (polybutadiene, 650 mPa · s), POLYVEST 130 (polybutadiene, 2.4 Pa · s) (Evonik Japan Co., Ltd.). The values in parentheses are the viscosities measured at 25 ° C. using a Brookfield type rotary viscometer conforming to JIS K7117-1: 1999.

As the liquid polymer (C2), a polyalkylene oxide compound (C23) may be used in addition to the polyα-olefin (C21), polydiene (C22) and a mixture thereof.

The polyalkylene oxide compound (C23) is not limited as long as it is a liquid polyalkylene oxide compound, and examples thereof include a reactant of an active hydrogen compound and an alkylene oxide (ethylene oxide, propylene oxide, butylene oxide, etc.).

Among these liquid polymers (C2), poly-α-olefin (C21) and polydiene (C22) are preferable, and poly-α-olefin (C21) is more preferable.

The liquid polymer (C2) does not contain the oil-soluble polymer (C3) and the silicone (C4).

As the oil-soluble polymer (C3), a polymer that uniformly dissolves in the base oil (D) that is liquid at 25 ° C. (the above properties are referred to as oil-soluble) can be used, and a polyvinyl alcohol alkyl ether (hydrogenated) can be used. Examples thereof include petroleum resins, liquid rubbers (natural liquid rubbers and synthetic liquid rubbers), thermoplastic elastomers (polydiene, block polymers containing polydiene blocks and polyolefin blocks, block copolymers containing polydiene blocks and polystyrene blocks, etc.). .. In addition to the above, known viscosity index improvers (for example, Introduction to Polymer Drugs, Sanyo Kasei Kogyo Co., Ltd., November 1992, 1st Edition, pp. 692-709) and known pour point lowering agents as oil-soluble polymers. (For example, Introduction to Polymer Drugs, Sanyo Kasei Co., Ltd., November 1992, 1st Edition, pp. 364-375) can also be used.

The base oil (D), which is liquid at 25 ° C., includes mineral oil, fats and oils, and monoalcohol fatty acid esters. The base oil (D) does not contain the branched alkyl ester (B2) of the dicarboxylic acid.

As the mineral oil, those refined by appropriately combining vacuum distillation, oil removal, solvent extraction, hydrocracking, solvent dewaxing, sulfuric acid washing, white clay refining, hydrorefining, etc. can be used, and as a trade name, Cosmo Oil can be used. Pure Spin G, Cosmo Pure Spin E, Cosmo SP-10, Cosmo SP-32 and Cosmo SC22 (above, Cosmo Oil Lubricants Co., Ltd., "Cosmo" and "Pure Spin" are registered trademarks of Cosmo Energy Holdings Co., Ltd. ), MC oil P-22, S-10S (above, Idemitsu Kosan Co., Ltd.), Stanol 40 (Exxon Mobile Corporation) and the like.

The fats and oils include fatty acids having 6 to 22 carbon atoms or esters of a mixture thereof and glycerin that are liquid at 25 ° C., and are contained in vegetable oils (rapeseed oil, soybean oil, palm oil, palm oil, olive oil, etc.). Examples thereof include chain fatty acid glyceride (trade names include, for example, Panaceto 875; Nichiyu Co., Ltd., "Panasate" is a registered trademark of the company) and fish oil.

The monoalcohol fatty acid ester includes a fatty acid having 6 to 22 carbon atoms or a mixture thereof and an ester of a monoalcohol having 1 to 22 carbon atoms, which is liquid at 25 ° C., and includes methyl oleate and butyl oleate. And methyl isostearate and the like.

Of these base oils (D), mineral oils and fats and oils are preferable, and mineral oils are more preferable, from the viewpoint of defoaming property. The oil-soluble polymer (C3) does not contain silicone (A) and silicone (C4).

The solutions of the oil-soluble polymer (C3) and the base oil (D) are easily available on the market, and as trade names, for example, San Ellis 934 (poly (meth) acrylate-based polymer, both of which are Sanyo Kasei Kogyo Co., Ltd., "San Ellis". Is a registered trademark of the company.), Acluve 136, 702, 812, 944 (poly (meth) acrylate-based polymer, Sanyo Kasei Kogyo Co., Ltd., "Acluve" is a registered trademark of the company), Archon M-135. , P-125 (petroleum resin, all Arakawa Chemical Industry Co., Ltd., "Arcon" is a registered trademark of the company), Claplen LIR30, LIR310, L-SBR (liquid rubber, all Claret Co., Ltd., "Claplen" (Registered trademark of the company), Septon 4033 (block polymer consisting of hydrogenated polydiene block and polystyrene block, Claret Co., Ltd., "Septon" is a registered trademark of the company) and the like.
The base oil (D) may be contained in the defoaming agent of the present invention together with the oil-soluble polymer (C3).

As the silicone (C4), silicone (A) having a weight average molecular weight (Mw) of 200,000 to 1,000,000 and silicone excluding silicone having a boiling point of 250 ° C. or lower can be used, and polydimethylsiloxane, α, ω-dihydroxy- Includes polydimethylsiloxane and α-aminopropylpolydimethylsiloxane.

The hydrophobic silica (C5) is not limited in size, type, etc. as long as it can be finely dispersed in the defoaming agent of the present invention, but the specific surface area of the hydrophobic silica by the BET method is at least 50 m ² / g. preferable.

The specific surface area by the BET method is based on JIS Z8830: 2013 "Method for measuring the specific surface area of powder (solid) by gas adsorption", and is a one-point method of gas adsorption method (carrier gas method) for hydrophobic silica in a dry state. Measure. A nitrogen-helium mixed gas is used as the carrier gas. Then, the specific surface area can be calculated from the value of the desorption peak.

As hydrophobic silica (C5), it is easily available from the market. For example, as trade names, Nippil SS-10, SS-40, SS-50 and SS-100 (Toso Silysia Chemical Ltd., "Nippil" are the same company. ), AEROSIL R972, RX200 and RY200 (Japan Aerosil Co., Ltd., "AEROSIL" is a registered trademark of Evonik Degussa Game Beher), TS-530, TS-610, TS-720 (Cabot Carbon Co., Ltd.) ), AEROSIL R202, R805 and R812 (Degusa Japan Co., Ltd.), REOLOSIL MT-10, DM-10 and DM-20S (Tokuyama Corporation, "REOLOSIL" is a registered trademark of the company), and SYLPHOBIC 100, 702, Examples thereof include 505 and 603 (Fuji Silysia Chemical Ltd., "SYLPHOBIC" is a registered trademark of the company).

Of the defoaming components (C), fluorine-modified silicone (C1), liquid polymer (C2) and oil-soluble polymer (C3) are preferable.

When a fluorine-modified silicone (C1), a liquid polymer (C2), an oil-soluble polymer (C3) and / or a silicone (C4) is contained, the content (% by weight) thereof is based on the weight of the silicone (A). It is preferably 1 to 150, more preferably 5 to 120, and particularly preferably 10 to 100. Within this range, the defoaming property is further improved.

When the hydrophobic silica (C5) is contained, the content (part by weight) of the hydrophobic silica (C5) is preferably 0.5 to 50, more preferably 1 to 30 based on the weight of the silicone (A). Is. Within this range, the defoaming performance is further improved.

The antifoaming agent of the present invention may further contain a solvent (E).
As the solvent (E), a branched carboxylic acid ester (B1) of silicone (A) and diol or a branched alkyl ester (B2) of dicarboxylic acid, and if necessary, a defoaming component (C) and / or a base oil (D) are used. The present invention is not particularly limited as long as it can be uniformly dissolved, and examples thereof include a ketone (E1) having 3 to 9 carbon atoms, a hydrocarbon (E2) having 5 to 12 carbon atoms, and an acetate ester (E3) having 3 to 6 carbon atoms.

Examples of the ketone (E1) having 3 to 9 carbon atoms include dimethyl ketone (acetone), methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), diisobutyl ketone (DIBK), cyclohexanone and the like.

Hydrocarbons (E2) having 5 to 12 carbon atoms include linear saturated hydrocarbons (n-pentane, n-hexane, n-heptane, n-dodecane, etc.) and branched saturated hydrocarbons (sec-pentane, tert-pentane, etc.). And isododecane, etc.), linear unsaturated hydrocarbons (1-pentene, 1-hexene, 1-dodecene, etc.) and branched unsaturated hydrocarbons (isopentene, 3-methyl-1-butene, 2,2-dimethyl-1-propene and Isododecene, etc.) and the like.

Examples of the acetic acid ester (E3) having 3 to 6 carbon atoms include methyl acetate, ethyl acetate, propyl acetate and butyl acetate.

When the solvent (E) is contained, the content (part by weight) of the solvent (E) can be appropriately adjusted depending on the handling property of the defoaming agent, the amount of the defoaming agent used, and the like.

The defoaming agent of the present invention comprises a branched carboxylic acid ester (B1) of a silicone (A) and a diol or a branched alkyl ester (B2) of a dicarboxylic acid, and, if necessary, a defoaming component (C) and / or a solvent (E). Can be uniformly mixed and prepared.

When the solvent (E) is contained, it is preferable to uniformly mix the solvent (E) at a temperature as low as possible (preferably 10 to 50 ° C, more preferably 20 to 40 ° C) in consideration of their volatility.

The defoaming agent of the present invention is more effective against non-aqueous foaming liquids, but is also effective against water-based foaming liquids. It is particularly effective as a defoaming agent for non-water-based coatings. Among the non-water-based coatings, it is effective for non-water-based paints used for painting industrial products and buildings, floor coating materials, rooftop waterproof paints, and the like. The water-based foaming liquid means a foaming liquid containing water, and the non-water-based foaming liquid (non-water-based coating or the like) means a foaming liquid containing no water (coating or the like).

The non-aqueous coating composition of the present invention contains the above-mentioned defoaming agent, filler and binder, but known components (filler and binder) other than the above-mentioned defoaming agent can be used.

As the filler, inorganic fine particles (mica, talc, kaolin, calcium carbonate, titanium oxide, barium sulfate, iron oxide, alumina, silica, carbon black, etc.) and organic fine particles (acrylic beads, silicon beads, polyethylene wax, etc.) can be used. ..

As the binder, polyester, polyurethane, polyamide, acrylic resin, phenol resin, alkyd resin, epoxy resin, polytetrafluoroethylene, polyvinylidene fluoride, polyvinyl chloride and a mixture thereof can be used.

The content (% by weight) of the defoaming agent in the non-aqueous coating composition is preferably 0.05 to 1, more preferably 0.1 to 0, based on the weights of the above-mentioned defoaming agent, filler and binder. It is .5.

The content (% by weight) of the filler is preferably 4 to 80, more preferably 9.5 to 70, based on the weights of the defoaming agent, the filler and the binder.

The content (% by weight) of the binder is preferably 19 to 95, more preferably 29.5 to 90, based on the weights of the defoaming agent, the filler and the binder.

The non-aqueous coating composition of the present invention may contain an additive that can be blended with a general non-aqueous coating composition within a range that does not affect the effect of the present invention. Such additives include hardeners, thickeners, plasticizers, preservatives, fungicides, fungicides, leveling agents, pigment dispersants, anti-skin agents, dryers, matting agents, UV absorbers. , Light stabilizers, antioxidants, hypocontamination agents, catalysts and the like.

The non-aqueous coating composition of the present invention can be produced by a conventionally known method. That is, it is obtained by uniformly mixing the above-mentioned defoaming agent, filler, binder and, if necessary, an additive.

Hereinafter, unless otherwise specified, parts mean parts by weight and% means parts by weight.
The weight average molecular weight was measured with the following equipment and conditions.
Measuring device; Tosoh Corporation, HLC-8220
Column; Tosoh Corporation, guard column HXL-H, TSKgel SuperHZ4000, TSKgel SuperHZ3000, TSKgel SuperHZ2000 and TSKgel SuperHZ2000 connected in series Detector; RI (differential refractometer)
Data processing; Tosoh Corporation, SC-8010
Column temperature 40 ° C
Solution medium; Tetrahydrofuran flow rate; 1.0 ml / min Standard material; Polystyrene sample; 1% Tetrahydrofuran solution

<Example 1>
2 parts of silicone (a1; Toray Dow Corning Co., Ltd., BY16-140, weight average molecular weight 500,000), 98 parts of 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid diester (b12) The mixture was uniformly mixed at 40 ° C. to obtain the defoaming agent (1) of the present invention.

<Examples 2 to 5>
Other than changing 2 parts of silicone (a1) and 98 parts of 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid diester (b12) to the composition and blending amount (parts) shown in Table 1. , Antifoaming agents (2) to (5) were obtained in the same manner as in Example 1.

<Silicone (A)>
(A1): Toray Dow Corning Co., Ltd., BY16-140, weight average molecular weight 500,000 (a2): Shin-Etsu Chemical Co., Ltd., KF9008, weight average molecular weight 720,000
KF9008 contains 80% decamethylcyclopentasiloxane (boiling point 207 ° C.). In Table 1, the amount of silicone having a weight average molecular weight of 720,000 is described in the column of (a1), and the amount of decamethylcyclopentasiloxane is described in the column of “decamethylcyclopentasiloxane”.
(A3): Toray Dow Corning Co., Ltd., SH200-1,000,000cs, weight average molecular weight: 230,000

<Branched carboxylic acid ester of diol (B1) or branched alkyl ester of dicarboxylic acid (B2)>
(B11): 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid monoester,
(B12): 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid diester (b21) Diisobutyl hexanedicarboxylate (b21)

<Defoaming component (C)>
(C11): Fluorine-modified silicone, Shin-Etsu Chemical Co., Ltd., FA-630
(C211): Polyα-olefin, Mitsui Chemicals, Inc., Lucant HC-2000 (95Pa · s, co-oligomer of ethylene-α-olefin)
(C31): Oil-soluble polymer, Sanyo Chemical Industries, Ltd., Acruve 944 (poly (meth) acrylate-based polymer), Acruve 944 contains 60% of mineral oil. In Table 1, the amount of the oil-soluble polymer is described in the column of (c31), and the amount of mineral oil is described in the column of base oil (D).

<Solvent (E)>
(E1): Methyl isobutyl ketone

<Comparison example>
According to Example 7 of Patent Document 1 (Japanese Unexamined Patent Publication No. 2002-301306), "defoaming agent-A" and "defoaming agent-D" are mixed at a ratio of 50:50 to make a comparative defoaming agent (defoaming agent for comparison). H1) was prepared.

<Performance evaluation>
1. 1. Preparation of non-aqueous coating composition for evaluation As an evaluation sample, the defoaming agents (1) to (5) of the present invention and the defoaming agent (H1) for comparison were used and uniformly mixed with the following compounding composition. , Non-aqueous coating compositions (1) to (5) and (H1) for evaluation were prepared {each number corresponds to the number of the defoaming agent obtained in Examples and Comparative Examples. }. In addition, a non-aqueous coating composition (blank) was prepared in the same manner except that the evaluation sample was not used.

Acrydic A-837 (* 1) 147 parts Typake R-930 (* 2) 228 parts Mineral Spirit 80 parts Efka RM1920 (* 3) 2 parts Acrydic A-848 (* 1) 508 parts Mineral Spirit 30 parts Evaluation sample (Antifoaming agent) 5 copies

* 1 Polyol resin, DIC Corporation, and "Acrydic" are registered trademarks of DIC Corporation.
* 2 Titanium dioxide, Ishihara Sangyo Co., Ltd., and "Typake" are registered trademarks of Ishihara Sangyo Co., Ltd.
* 3 The thickener, BASF Japan Ltd., and "efka" are registered trademarks of BASF Society for Europe.

2. 2. Evaluation of defoaming performance 1000 parts each of non-aqueous coating compositions (1) to (5), (H1) and (blank) are diluted with mineral spirit and adjusted to 70 KU (25 ° C) with a Stormer viscometer. After that, the temperature was adjusted to 25 ° C, and the tin plate was coated with a medium-hair wool roller (Otsuka Brush Manufacturing Co., Ltd.) at 25 ° C so that the coating amount was 50 g (per 30 cm x 30 cm). The time until the bubbles disappeared was measured, and the defoaming performance was judged according to the following criteria. The results are shown in Table 2.

◯: Bubbles disappeared in less than 15 seconds
X: It took more than 30 seconds for the bubbles to disappear

3. 3. Evaluation of Finished Appearance 1000 parts each of the non-aqueous coating compositions (1) to (5), (H1) and (blank) were diluted with mineral spirit and adjusted to 40 KU (25 ° C) with a stormer viscometer. After that, the temperature was adjusted to 25 ° C, the coating was applied to a wet film thickness of 0.026 mm to a size of 10 cm x 10 cm, the number of craters in the coating film after drying at 25 ° C for 24 hours was counted, and the same operation was performed 3 times. The finished appearance was judged from the total of the above according to the following criteria. The results are shown in Table 2.

○: 1 or less craters ×: 3 or more craters

As shown in Table 2, the defoaming agent of the present invention was superior in the finished appearance of the coating film as compared with the defoaming agent for comparison.

Claims (3)

A defoaming agent comprising a silicone (A) having a weight average molecular weight of 200,000 to 1,000,000 and a branched carboxylic acid ester (B1) of a diol or a branched alkyl ester (B2) of a dicarboxylic acid. The branched carboxylic acid ester (B1) of the diol or the branched alkyl ester (B2) of the dicarboxylic acid is 2,2,4-trimethyl-1,3-pentanediol 2-methylpropanoic acid monoester (b11), 2,2,4. The antifoaming agent according to claim 1, which is at least one selected from the group consisting of trimethyl-1,3-pentanediol 2-methylpropanoic acid diester (b12) and diisobutyl hexanedicarboxylic acid (b21). A non-aqueous coating composition comprising the defoaming agent, filler and binder according to claim 1 or 2.