Surface conditioner, aqueous coating composition, article, and method for forming multilayer coating film

Abstract

The present invention provides: a surface conditioner which is capable of preventing the occurrence of a blister during the formation of a multilayer coating film by a wet-on-wet system, and which does not hamper overcoatability; an aqueous coating composition which contains the surface conditioner; an article which is coated with a coating agent that contains the surface conditioner; and a method for forming a multilayer coating film with use of an aqueous coating material that contains the surface conditioner.　This surface conditioner for an aqueous coating material contains: a polymer (A) which has an SP value of 6-12 and a weight average molecular weight of 200-1,000,000, and includes at least three repeating units; and organic solid fine particles (B) which are in a solid state in the surface conditioner at 25°C.

Description

Surface conditioner, water-based coating composition, article, and method for forming multi-layer coating film

[0001] The present invention relates to a surface conditioner, a water-based coating composition, an article, and a method for forming a multi-layer coating film.

[0002] In the painting process for automobile bodies and the like, a multi-layer coating is usually formed on the substrate by applying a primer coat (e.g., electrodeposition coating), a first coat, a second coat, and, if necessary, a clear coat, for the purpose of imparting corrosion resistance and design. A widely used method for forming such a multi-layer coating on an automobile body is, for example, a three-coat, two-bake (3C2B) method, in which a primer coat is formed on the substrate, followed by painting a first coat, baking and curing, painting a second coat, painting a clear coat, and baking and curing in that order.

[0003] In contrast, in recent years, CO ２ For the purpose of reducing costs and saving energy, a method is being considered for forming a multi-layer coating film using a so-called wet-on-wet method in which the bake-hardening step after the application of the first coating is omitted and the following steps are carried out in sequence: application of the first coating film, preheating (preheating), application of the second coating film, preheating, application of the clear coating film, and bake-hardening. In other words, a method is being considered for forming a multi-layer coating film using a so-called wet-on-wet method in which an upper layer of coating is applied without hardening the coating film at the application stage of each coating film layer, and multiple layers are baked and hardened at the same time.

[0004] Furthermore, in recent years, from the viewpoint of environmental issues and health effects, there has been a shift from solvent-based paints to water-based paints with the aim of reducing volatile organic compounds (VOCs).In the painting of automobile bodies, too, there has been an active movement to use water-based first and second paints from the viewpoint of VOC reduction, and in particular, there is a demand for water-based paints as the first and second paints in the 3C1B system.

[0005] To make a paint water-based, it is necessary to increase the solubility and dispersibility of the resin that forms the paint film. To achieve this, methods have been used such as polarizing the resin by introducing hydrophilic groups into the resin or adding surfactants. However, water-based paints containing polarized resins or surfactants have the problem of being prone to foaming and stabilizing air bubbles. Therefore, preventing air bubble entrapment during the paint manufacturing and application processes, and preventing air bubbles from remaining in the dried paint film and the occurrence of paint film defects such as voids, are important issues for water-based paints. Various surface conditioners for water-based paints have been proposed as additives to prevent air bubble entrapment during the paint manufacturing and application processes.

[0006] For example, Patent Document 1 discloses an anti-foaming agent for aqueous paints, which is added to aqueous paints to prevent foaming during the baking process and contains a copolymer of an ether group-containing alkyl (meth)acrylate monomer (A) and an (ether group-free) alkyl (meth)acrylate monomer (B). Patent Document 2 discloses a defoaming agent for aqueous paints, which is obtained by dissolving polyoxyethylene hydrogenated castor oil triisostearate and one or more selected from polyalkyl vinyl ether, polybutadiene, polybutene, and polyisoprene in a specific hydrophobic solvent.

[0007] Furthermore, Patent Document 3 discloses a silicone-based defoaming agent, which is a defoaming agent composition comprising an organic acid ester-modified organopolysiloxane having a specific structure and finely powdered silica. This defoaming agent composition is said to be capable of exhibiting high defoaming performance, dispersibility, and paintability in various coating liquids.

[0008] JP 2010-100796 A JP 2010-075779 A JP 2010-279889 A

[0009] However, when forming a multilayer coating film using the wet-on-wet method, not only air bubbles generated during the production and application of the first and second coating materials, but also air bubbles generated by air being entrained during the production and application of the first and second coating materials (entrained bubbles) remain in the uncured multilayer coating film, and during the bake-hardening process, "pull-up" may occur due to the entrained bubbles remaining in the uncured multilayer coating film. Until now, no research has been conducted from the perspective of preventing the occurrence of "pull-up" due to entrained bubbles in such multilayer coating films. Therefore, the present inventors focused on the problem of "preventing not only air bubbles entrained during the production and application of the first and second coating materials, but also bubbles generated by air entrained in the uncured multilayer coating film when forming a multilayer coating film using the wet-on-wet method," and investigated means for solving this problem.

[0010] Here, Patent Documents 1 and 2 refer to prevention of spalling in a single-layer coating film, but do not focus on the problem of preventing spalling in a multi-layer coating film caused by bubbles entrained during the production and application of the first and second paints when forming a multi-layer coating film by a wet-on-wet method. Also, Patent Document 3 only evaluates the defoaming performance, dispersibility, and paintability of the defoaming agent composition, and, like Patent Documents 1 and 2, does not focus on the problem of preventing spalling in a multi-layer coating film caused by bubbles entrained during the production and application of the first and second paints when forming a multi-layer coating film by a wet-on-wet method.

[0011] In addition, generally, the silicone-based antifoaming agent as described in Patent Document 3 has excellent foam-breaking properties due to its extremely low surface tension, but the bleeding of the silicone component onto the coating film surface causes repellency or inhibits topcoatability.Even if these adverse effects are not confirmed in the short term in laboratory-scale tests or actual coating processes, one trouble in mass production may cause a large loss, so in particular, in applications that emphasize high appearance, coating systems with multi-layer coatings, large-scale coating systems such as line coating, etc., the incorporation of silicone-based materials is often avoided, and the use of silicone-based antifoaming agents is also avoided as a surface conditioner.

[0012] Therefore, the present invention has been made in consideration of the above circumstances, and aims to provide a surface conditioner that prevents bubble entrainment during paint production and application, is capable of preventing the formation of cracks when forming a multi-layer paint film by a wet-on-wet method, and does not inhibit overcoatability, a water-based paint composition containing this surface conditioner, an article coated with a coating agent containing this surface conditioner, and a method for forming a multi-layer paint film using a water-based paint containing this surface conditioner.

[0013] As a result of extensive research to solve the above problems, the present inventors have found that by adding, as components of a surface conditioner, a polymer having an SP value and weight-average molecular weight within a specific range and having at least three or more repeating units, and organic solid fine particles, it is possible to provide a surface conditioner for water-based paints that can prevent the formation of cracks when forming a multi-layer coating film by a wet-on-wet method and that does not inhibit overcoating properties, and have completed the present invention based on this finding.

[0014] That is, the present invention provides a surface conditioner for water-based paints, characterized in that it comprises: a polymer (A) having an SP value of 6 to 12, a weight-average molecular weight of 200 to 1,000,000, and at least three repeating units; and organic solid fine particles (B) that are in a solid state in the surface conditioner at 25°C.

[0015] In one embodiment of the present invention, the polymer (A) may be one or more polymers selected from the group consisting of polyvinyl alkyl ether, polybutadiene, polybutene, polyalphaolefin, polyalkyl(meth)acrylate, copolymer of dibasic acid ester, polyfatty acid vinyl ester, polyalkylene glycol and its derivative, polyamide, polyglycerin fatty acid ester, and polyester.

[0016] In another embodiment of the present invention, the organic solid fine particles (B) may be one or more solid fine particles selected from the group consisting of amide, urea, polyethylene, polyethylene oxide, acid-modified polyethylene, ethylene-vinyl acetate copolymer, ethylene (meth)acrylic acid copolymer, polypropylene, acid-modified polypropylene, and hydrogenated castor oil. In this case, the amide may be a fatty acid diamide obtained by reacting a fatty acid selected from the group consisting of alkyl fatty acids and hydroxy fatty acids, containing at least one hydroxy fatty acid, with a diamine containing one or more diamines selected from the group consisting of alkylenediamines having 2 to 6 carbon atoms and m-xylylenediamine.

[0017] In still another embodiment of the present invention, the organic solid fine particles (B) may have a crystal aspect ratio of 1.1 to 100.

[0018] In still another embodiment of the present invention, the organic solid fine particles (B) may have a mode diameter of 0.1 to 150 μm.

[0019] In yet another embodiment of the present invention, the surface conditioner may further comprise an organic medium (C) other than water that is liquid at 25° C., and the organic medium (C) may have 0 to 2 repeating units. In this case, the organic medium (C) may be one or more selected from the group consisting of hydrocarbon oils, alcohols, glycol ethers, glycol esters, and polyhydric alcohol fatty acid esters.

[0020] Another aspect of the present invention is a water-based coating composition comprising the above-mentioned surface conditioner and a water-based resin.

[0021] Furthermore, according to yet another aspect, the present invention provides an article coated with a coating agent containing the above-described surface conditioner.

[0022] Furthermore, from yet another aspect, the present invention is a method for forming a multilayer coating film, which includes a film-forming step of successively applying at least two or more types of water-based paints wet-on-wet to the surface of an object to be coated, and then simultaneously heating and curing the water-based paints applied to the object to form at least two or more coating layers, wherein at least one of the two or more types of water-based paints contains the above-mentioned surface conditioner.

[0023] In one aspect of the present invention, the two or more types of water-based paints used in the film-forming step include a first water-based paint containing a color pigment and a second water-based paint containing a lustrous pigment, and at least one of the first water-based paint and the second water-based paint contains the surface conditioner. In the film-forming step, the first water-based paint, the second water-based paint, and the clear paint may be applied successively wet-on-wet, and then the first water-based paint, the second water-based paint, and the clear paint may be simultaneously heat-cured to form a first water-based resin coating film, a second water-based resin coating film, and a clear coating film laminated in this order from the side of the substrate to the surface of the substrate.

[0024] According to the present invention, by containing a specific polymer and organic solid fine particles as components of the surface conditioner, it is possible to provide a surface conditioner that can prevent cracks from occurring when forming a multi-layer coating film by the wet-on-wet method and that does not inhibit the overcoatability when forming a multi-layer coating film, a water-based paint composition containing this surface conditioner, an article coated with a coating agent containing this surface conditioner, and a method for forming a multi-layer coating film using a water-based paint containing this surface conditioner.

[0025] Preferred embodiments of the present invention will now be described in detail.

[0026] [Surface Conditioner] The surface conditioner of the present invention is an additive that functions as an antifoaming agent to suppress the generation of bubbles during the production and application of a paint due to the inclusion of a large amount of water, polarized resin, various surfactants, etc. in the water-based paint, and / or functions as a bubble inhibitor to prevent bubbles remaining in the uncured multilayer paint film from appearing as bubbles in the paint film during heat curing. Furthermore, the surface conditioner of the present invention contains as essential components a polymer (A) having a specific SP value and weight-average molecular weight and containing at least three or more repeating units, and organic solid fine particles (B). This makes it possible to provide a surface conditioner for water-based paint that can prevent bubbles from occurring when forming a multilayer paint film using a wet-on-wet method and does not inhibit the topcoatability of the multilayer paint film when it is formed. Furthermore, when a topcoat paint such as a clear paint is applied wet-on-wet in addition to the first and second paints and simultaneously baked and cured, or when a multi-layer paint film is recoated for repair purposes after curing, the inclusion of the surface conditioner of the present invention in the first or second paint can prevent defects such as repellency and deterioration of smoothness in the topcoat or recoat paint. In particular, for clear paints used as topcoats, there is a trend to minimize the amount of organic solvent used (high solids) in order to reduce VOCs. When a paint becomes high solids, its hydroxyl value increases, which tends to increase its polarity and deteriorate its wettability to substances. Deterioration of wettability makes the paint more susceptible to the influence of repellent substances present in the second paint, making it more susceptible to paint film defects such as repellency. Even in such cases, even if the surface conditioner of the present invention is contained in the first or second paint, this surface conditioner has the effect of not worsening the wettability of the clear paint to the paint film to which it is applied, thereby preventing defects such as repellency and deterioration of smoothness.

[0027] Here, "anti-wheezing" in the present invention refers to the ability to prevent "wheezing" that occurs when forming a multilayer coating film using a wet-on-wet method, not only from air bubbles that occur during the production and application of the first and second paints, but also from air bubbles (entrained bubbles) that occur due to air entrainment during the production and application of the first and second paints, remaining in the uncured multilayer coating film, and then caused by the entrained bubbles remaining in the uncured multilayer coating film during the bake-hardening process. Furthermore, "topcoatability" in the present invention refers to the ability to coat an already coated coating film (hereinafter referred to as the "undercoat film") on its surface to form a coating film (hereinafter referred to as the "uppercoat film") without causing repellency or the like, and the ability to prevent problems such as peeling between the upper and lower coats, in a coating system consisting of multiple layers.

[0028] (Polymer (A)) The polymer (A) according to the present invention is a component for exhibiting defoaming and anti-spreading properties, and is added to enhance the penetration of a surface conditioner into a foam film. The polymer (A) used herein is a polymer having an SP value of 6 to 12, a weight-average molecular weight of 200 to 1,000,000, and at least three repeating units. The polymer (A) according to the present invention may have an SP value of 6 to 12, a weight-average molecular weight of 200 to 1,000,000, and three or more repeating units derived from the monomers used as raw materials in synthesizing the polymer. In other words, the polymer (A) according to the present invention includes not only polymers that are general polymeric compounds, but also trimers and oligomers.

[0029] The polymer (A) is selected from those having a liquid or rubbery form, or those that are solid at 25° C. but are in a liquid state in the liquid medium contained in the composition at 25° C. and do not exist in a solid state (i.e., do not exist as fine particles in the surface conditioner). Liquid polymers can be used alone, and rubbery and solid polymers are used by dissolving them in a liquid component.

[0030] <SP Value / Weight Average Molecular Weight> The SP value of the polymer (A) according to the present invention is in the range of 6 to 12. If the SP value is less than 6, defects in the appearance of the coating film, such as repellency and bumps, may occur. On the other hand, if the SP value exceeds 12, the defoaming effect may be poor, and satisfactory defoaming and anti-spreading properties may not be obtained. In order to further improve defoaming and anti-spreading properties, the SP value is preferably 7.5 to 10.5, more preferably 8.0 to 10.0, even more preferably 8.0 to 9.5, and most preferably 8.5 to 9.5.

[0031] The SP value in the present invention is a value calculated by the Fedors method, and the unit is (cal / cm ３ ) １／２ The Fedors method is a method for estimating the SP value from the molecular structure, and uses the cohesive energy (cal / mol) and molar volume (cm ３ The SP value can be estimated from the relationship between the SP value and the solubility of the compound (mol / mol).

[0032] The weight-average molecular weight of the polymer (A) according to the present invention is in the range of 200 to 1,000,000. If the weight-average molecular weight is less than 200, sufficient defoaming and anti-spreading properties cannot be exhibited. On the other hand, if the weight-average molecular weight exceeds 1,000,000, it becomes difficult to uniformly disperse the polymer (A) in the paint, resulting in problems such as repellency and denting. In order to further improve the defoaming and anti-spreading properties, the weight-average molecular weight is preferably 250 to 1,000,000, more preferably 300 to 300,000, and even more preferably 400 to 20,000.

[0033] The weight average molecular weight in the present invention is a value calculated from a chromatogram measured by gel permeation chromatography (GPC) based on the molecular weight of standard polystyrene.

[0034] <Specific Examples> The polymer (A) according to the present invention is a polymer having the above-mentioned SP value and weight-average molecular weight and having at least three repeating units. Here, "a polymer having at least three repeating units" refers to a compound having a degree of polymerization of 3 or more, with monomer units as repeating units, or a derivative thereof. As the polymer (A), for example, one or more polymers selected from the group consisting of polyvinyl alkyl ether, polybutadiene, polybutene, polyalphaolefin, polyalkyl(meth)acrylate, copolymers of dibasic acid esters, polyfatty acid vinyl esters, polyalkylene glycols and their derivatives, polyamides, polyglycerin fatty acid esters, and polyesters can be suitably used.

[0035] The polyvinyl alkyl ether can be obtained by polymerizing a vinyl ether monomer having an alkyl group having 1 to 18 carbon atoms. Examples of this vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, tert-butyl vinyl ether, hexyl vinyl ether, n-octyl vinyl ether, 2-ethylhexyl vinyl ether, isononyl vinyl ether, dodecyl vinyl ether, tetradecyl vinyl ether, hexadecyl vinyl ether, and octadecyl vinyl ether, and one or more of these monomers can be selected and used as desired.

[0036] Polybutadiene includes 1,3-butadiene (CH ２ =CH-CH=CH ２ ), or 1,2-butadiene (CH ２ =C=CH-CH ３ ) homopolymers and copolymers thereof can be used. Commercially available polybutadienes may also be used. Commercially available polybutadienes include homopolymers, hydrogenated types, terminal carboxylic acid groups, and terminal hydroxyl groups. One or more of these polymers can be selected and used as desired.

[0037] As the polybutene, a 1-butene homopolymer or a 1-butene and isobutene copolymer can be used. Commercially available polybutenes may also be used. Commercially available polybutenes include a 1-butene and isobutene copolymer, a 1-butene homopolymer, and a hydrogenated type. One or more of these polymers can be arbitrarily selected and used.

[0038] Examples of polyalphaolefins include poly(1-hexene), poly(1-octene), poly(1-decene), poly(1-dodecene), and ethylene-propylene copolymers, and one or more of these can be selected and used as desired.

[0039] Examples of polyalkyl (meth)acrylates include polymers or copolymers of methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, hexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, oleyl (meth)acrylate, behenyl (meth)acrylate, benzyl (meth)acrylate, cyclohexyl (meth)acrylate, and isobornyl (meth)acrylate.

[0040] Examples of copolymers of dibasic acid esters include polymers or copolymers of monoesters or diesters of maleic acid, and polymers or copolymers of monoesters or diesters of fumaric acid.

[0041] Examples of polyfatty acid vinyl esters include polymers or copolymers of fatty acid vinyl esters (monomers) such as vinyl acetate, vinyl pivalate, vinyl propionate, vinyl butyrate, vinyl caproate, vinyl caprylate, vinyl caprate, vinyl laurate, vinyl palmitate, vinyl octylate, vinyl 2,2-dimethyloctanoate, vinyl neononanoate, vinyl neodecanoate, and vinyl neoundecanoate.

[0042] Examples of polyalkylene glycols and derivatives thereof include polypropylene glycol, polybutylene glycol, polyethylene glycol propylene glycol, polypropylene glycol monobutyl ether, alkylene oxide adducts of hydrogenated castor oil, and further polypropylene glycols adducted to polyhydric alcohols such as glycerin, trimethylolpropane, and sugars, polybutylene glycol adducts, and polypropylene glycol adducts of polyamides.

[0043] In addition to the above-mentioned polyalkylene glycol derivatives, polyoxyalkylene aliphatic ethers, polyoxyalkylene aromatic ethers, polyoxyalkylene fatty acid esters, polyoxyalkylene polyhydric alcohol ethers, polyoxyalkylene alkylamides, polyoxyethylene-polyoxypropylene block copolymers, and polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymers can also be used.

[0044] Examples of polyoxyalkylene aliphatic ethers include polyoxypropylene aliphatic ethers, polyoxyethylene aliphatic ethers, and polyoxyethylene-polyoxypropylene aliphatic ethers. Examples of polyoxyalkylene aromatic ethers include polyoxypropylene aromatic ethers, polyoxyethylene aromatic ethers, and polyoxyethylene-polyoxypropylene aromatic ethers. Examples of polyoxyalkylene fatty acid esters include polyoxypropylene fatty acid esters, polyoxyethylene fatty acid esters, and polyoxyethylene-polyoxypropylene fatty acid esters. Examples of polyoxyalkylene polyhydric alcohol ethers include those obtained by adding alkylene oxides such as ethylene oxide, propylene oxide, and butylene oxide to polyhydric alcohols such as glycerin, polyglycerin, trimethylolpropane, pentaerythritol, monosaccharides, disaccharides, trisaccharides, oligosaccharides, polysaccharides, sorbitol, and sorbitan having a glucose or fructose skeleton. The polyoxyethylene-polyoxypropylene block copolymer or polyoxyethylene-polyoxypropylene-polyoxyethylene block copolymer that can be used is, for example, one in which the total mass of ethylene oxide blocks in the copolymer molecule is 10% by mass to 50% by mass, more preferably 10% by mass to 20% by mass, and the weight-average molecular weight of the propylene oxide blocks is 700 to 4000, more preferably 3000 to 4000. Within the above ranges, it is more desirable that the block copolymer be a liquid type.

[0045] Furthermore, as the polyalkylene glycol derivative, a copolymer of polyalkylene glycol (meth)acrylate and a fatty acid vinyl ester can also be used. Examples of the copolymer include copolymers formed by combining a polyalkylene glycol (meth)acrylate such as methoxypolyethylene glycol (meth)acrylate, stearoxypolyethylene glycol (meth)acrylate, nonylphenoxypolypropylene glycol (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, polyethylene glycol propylene glycol (meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, and polyethylene glycol propylene glycol di(meth)acrylate with the above-mentioned fatty acid vinyl ester.

[0046] As polyamides, polymers obtained by dehydration condensation of polycarboxylic acids and polyamines can be used. Among the polycarboxylic acids, dicarboxylic acids having 4 to 44 carbon atoms can be used. Examples of such dicarboxylic acids include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, and dimer acid. Dimer acids are polymerized fatty acids obtained by polymerizing (dimerizing) unsaturated fatty acids (e.g., unsaturated fatty acids having 18 or 22 carbon atoms) obtained from vegetable oils such as soybean oil, tall oil, linseed oil, and cottonseed oil. Dimer acids having 36 or 44 carbon atoms are generally commercially available. As tricarboxylic acids, tricarboxylic acids having 4 to 54 carbon atoms can be used. Examples of such tricarboxylic acids include trimer acid and trimesic acid. Trimer acid is a polymerized fatty acid in which the trimer acid content is increased by dimer acid-based dimer acid purification or the like, and trimer acid having 54 carbon atoms is generally commercially available. Among polyamines, examples of diamines include 1,2-diaminoethane (ethylenediamine: EDA), 1,2-diaminopropane (propylenediamine: PDA), 1,4-diaminobutane (tetramethylenediamine: TMDA), 1,6-diaminohexane (hexamethylenediamine: HMDA), 1,8-diaminooctane (octamethylenediamine: OMDA), trimethylhexamethylenediamine, 1,12-diaminododecane (dodecamethylenediamine: OMDA), and the like. Examples of the diamine that can be used include aliphatic diamines such as o-xylylenediamine, m-xylylenediamine (MXDA), p-xylylenediamine (PXDA), diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone, and methylenebischloroaniline, and alicyclic diamines such as piperazine, isophoronediamine, and 1,3-bisaminomethylcyclohexane. Examples of the triamine that can be used include aliphatic triamines such as diethylenetriamine and other triamines having 2 to 54 carbon atoms.Furthermore, as the amines used in synthesizing the amide of the present invention, diamines or triamines derived from polymerized fatty acids, which are polymerized fatty acid derivatives, can also be used. Examples of such polymerized fatty acid derivatives include dimer diamine (DDA), which is a dimer acid derivative, and trimer triamine (TTA), which is a trimer acid derivative. Dimer diamine is a dimer acid derivative in which the two terminal carboxyl groups of the above-mentioned dimer acid are substituted with primary aminomethyl groups or amino groups, and generally commercially available products can be used. Furthermore, trimer triamine is a trimer acid derivative in which the three terminal carboxyl groups of the above-mentioned trimer acid are substituted with primary aminomethyl groups or amino groups, and generally commercially available products can be used.

[0047] Examples of polyglycerol fatty acid esters include polyglycerol caprylate, polyglycerol 2-ethylhexanoate, polyglycerol caprate, polyglycerol laurate, polyglycerol myristate, polyglycerol stearate, polyglycerol oleate, polyglycerol isostearate, polyglycerol behenate, and polyglycerol condensed ricinoleate, and one or more of these may be selected and used as desired.

[0048] Examples of polyesters include condensation polymers of hydroxy fatty acids, and condensation polymers of polymerized fatty acids such as dimer acids and diols.

[0049] Of the specific examples given above, in order to improve the anti-pile properties and recoatability, it is preferable to use polyalkylene glycol and its derivatives, polyalkyl acrylate, polyvinyl alkyl ether, polybutene, polyglycerin fatty acid ester, etc.

[0050] <Content> The content of the above-mentioned polymer (A) is preferably 10% by mass to 99.9% by mass, when the total mass of all components in the surface conditioner is 100% by mass. By setting the content of polymer (A) to 10% by mass to 99.9% by mass, sufficient defoaming properties and anti-spreading properties can be exhibited. In order to further improve the defoaming properties and anti-spreading properties, it is more preferable that the content of polymer (A) be 20% by mass to 70% by mass.

[0051] (Organic solid fine particles (B)) The organic solid fine particles (B) according to the present invention are a component for exhibiting defoaming properties and preventing breakage, and are added to enhance the foam-breaking effect of the surface conditioner and to enhance breakage prevention. The organic solid fine particles (B) are selected from materials having a melting point of at least 50°C or higher, and are fine particles that are solid at 25°C. Such organic solid fine particles (B) are in a solid state in the liquid medium contained in the composition at 25°C. Furthermore, the organic solid fine particles (B) are selected so that they do not dissolve in the surface conditioner at 25°C or do not change the shape of their primary particles.

[0052] Here, the term "primary particles" in the present invention refers to isolated particles that are not further divided into smaller particles even when diluted with a specific medium. Furthermore, whether the organic solid fine particles (B) are in a solid state in the liquid medium contained in the surface conditioner at 25°C can be determined by a known qualitative method. For example, the organic solid fine particles are dispersed in the liquid medium contained in the composition in an amount not exceeding 50% by mass, and the dispersion is then filtered or centrifuged to separate the non-fluid components, after which their melting points are measured.

[0053] <Particle Shape> The organic solid fine particles (B) are solid fine particles made of an organic compound. Furthermore, when the particle size distribution is measured by a laser diffraction / scattering measurement method or the like, the particle diameter preferably has a peak in the range of 0.1 to 150 μm. That is, the peak particle diameter (also referred to as the "mode diameter") of the organic solid fine particles (B) is preferably in the range of 0.1 to 150 μm, more preferably 2 to 150 μm, and even more preferably 2 to 50 μm. When the peak particle diameter of the organic solid fine particles (B) is within the above range, a surface conditioner having particularly excellent anti-flake properties can be obtained.

[0054] As for the particle shape, particles with an uneven surface are more preferable than spherical particles, and porous particles or particles with thorn-like protrusions are more preferable. Such particles may be, for example, clusters of fine particles having an aspect ratio of 1.1 to 100. In particular, when such clusters are used, the fine particle surfaces can favorably retain a mixed liquid comprising an antifoaming liquid component (e.g., polymer (A)) and an organic medium (C), resulting in particularly excellent anti-flake properties. The aspect ratio of the primary particles can be controlled in the process of producing the organic solid fine particles (B) by appropriately adjusting the medium for dissolution and precipitation, the temperature during precipitation and crystal growth of the fine particles, and, if necessary, the time for maintaining the temperature during precipitation and crystal growth of the fine particles.

[0055] If the aspect ratio is less than 1.1, it is difficult to form clusters, making it difficult to retain the defoaming liquid component, and it is difficult to obtain excellent anti-wrinkle properties. On the other hand, if the aspect ratio exceeds 100, the voids in the clusters become too large, making it difficult to retain the defoaming liquid component, and in this case too, it is difficult to obtain excellent anti-wrinkle properties. From the viewpoint of further improving anti-wrinkle properties, the aspect ratio is more preferably in the range of 1.5 to 50, even more preferably in the range of 1.5 to 30, and most preferably in the range of 1.5 to 11.0.

[0056] The aspect ratio of the primary fine particles can be calculated by measuring the shape of isolated fine particles during TEM or SEM observation. Specifically, it can be calculated, for example, by the following method. The fine particles to be measured are diluted and suspended in a suitable volatile organic solvent in which the fine particles do not dissolve, and then dropped onto a TEM observation grid or a SEM observation sample mount, and dried to prepare an observation sample. The type of solvent and the amount of dilution are appropriately adjusted so that the fine particles are isolated. The magnification of the sample prepared using TEM or SEM is set so that the isolated fine particles can be easily observed, and the shape of the isolated fine particles is confirmed. If the shape of the fine particles can be considered elliptical, the distances between the minor axis and the major axis are measured, and the value of the major axis / minor axis is calculated. Similar measurements are performed on at least 10 or more fine particles, and the average is used as the aspect ratio of the fine particles. If the fine particles are fibrous and difficult to consider as elliptical, the median of the measured fiber widths is used as the fiber width, and the value of the fiber length / fiber width is calculated. The same measurement is carried out for at least 10 or more isolated fibrous particles, and the average of the measurements is taken as the aspect ratio of the fibrous particle.

[0057] <Specific Examples> The organic solid fine particles (B) are not particularly limited, but for example, solid fine particles of one or more kinds selected from the group consisting of amide, urea, polyethylene, polyethylene oxide, acid-modified polyethylene, ethylene-vinyl acetate copolymer, ethylene (meth)acrylic acid copolymer, polypropylene, acid-modified polypropylene, and hydrogenated castor oil can be suitably used.

[0058] Amides can be obtained, for example, by a condensation reaction between fatty acids and amines. The conditions for the condensation reaction (e.g., reaction temperature, mixing ratio of each component, etc.) can be appropriately set using known methods. For example, the raw materials, fatty acids and amines, are placed in a reaction vessel such as a four-neck flask, and the raw materials are stirred in an inert gas atmosphere (e.g., under a nitrogen gas flow) to form a mixture. The raw material mixture is then heated and subjected to a polycondensation reaction at 150°C to 200°C for 2 to 10 hours, thereby synthesizing a fatty acid amide. Examples of fatty acids that can be used include monocarboxylic acids, dicarboxylic acids, and tricarboxylic acids, and examples of amines that can be used include monoamines, diamines, and triamines.

[0059] Examples of monocarboxylic acids that can be used include saturated aliphatic monocarboxylic acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, hydrogenated castor oil fatty acid (a fatty acid having a hydroxyl group, such as 12-hydroxystearic acid (hereinafter referred to as "12-HSA") obtained by saponifying hydrogenated castor oil), arachidic acid, and behenic acid (behenic acid), as well as unsaturated aliphatic monocarboxylic acids such as oleic acid, linoleic acid, ricinoleic acid, linolenic acid, eicosenoic acid, erucic acid (erucic acid), and mixed fatty acids obtained from natural fats and oils (tall oil fatty acid, rice bran fatty acid, soybean oil fatty acid, beef tallow fatty acid, etc.). Among these monocarboxylic acids, it is preferable to include at least a hydroxy fatty acid such as 12-HSA as the monocarboxylic acid in order to improve the defoaming and anti-fizzing properties of water-based paints. That is, the amide used as the organic solid fine particles (B) of the present invention is preferably an amide in which at least one of the fatty acids is a hydroxy fatty acid.

[0060] As the dicarboxylic acid, for example, a dicarboxylic acid having 4 to 44 carbon atoms can be used, and examples of such dicarboxylic acids include succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, and dimer acid.

[0061] As the tricarboxylic acid, for example, a tricarboxylic acid having 4 to 54 carbon atoms can be used, and examples of such tricarboxylic acids include trimer acid and trimesic acid.

[0062] Examples of monoamines include ethylamine, monoethanolamine, propylamine, butylamine, pentylamine, hexylamine, octylamine, decylamine, laurylamine, myristylamine, cetylamine, stearylamine, 12-hydroxystearylamine, and behenylamine.

[0063] Examples of diamines that can be used include aliphatic diamines such as 1,2-diaminoethane (ethylenediamine: EDA), 1,2-diaminopropane (propylenediamine: PDA), 1,4-diaminobutane (tetramethylenediamine: TMDA), 1,6-diaminohexane (hexamethylenediamine: HMDA), 1,8-diaminooctane (octamethylenediamine: OMDA), trimethylhexamethylenediamine, and 1,12-diaminododecane (dodecamethylenediamine: DMDA); aromatic diamines such as o-xylylenediamine, m-xylylenediamine (MXDA), p-xylylenediamine (PXDA), diaminodiphenylmethane, diaminodiphenyl ether, diaminodiphenyl sulfone, and methylenebischloroaniline; and alicyclic diamines such as piperazine, isophoronediamine, and 1,3-bisaminomethylcyclohexane, which have 2 to 54 carbon atoms.

[0064] As the triamine, for example, a triamine having 2 to 54 carbon atoms, such as an aliphatic triamine such as diethylenetriamine, can be used.

[0065] Furthermore, the amines used in synthesizing the amide of the present invention may be diamines or triamines derived from polymerized fatty acids, such as dimer diamine (DDA) and trimer triamine (TTA).

[0066] The compounds used as the above-mentioned fatty acids and amines can be used singly or in combination of two or more.

[0067] Here, from the viewpoint of further enhancing the anti-spreading properties, the amide is preferably a diamide. Diamides can be obtained by reacting a fatty acid with a diamine or a monoamine with a dicarboxylic acid. Among diamides, fatty acid diamides obtained by reacting the following fatty acids with the following diamines are particularly preferred. The fatty acids used in the synthesis of the fatty acid diamide are selected from the group consisting of alkyl fatty acids (saturated fatty acids) and hydroxy fatty acids, and contain at least one hydroxy fatty acid. Furthermore, the diamines used in the synthesis of the fatty acid diamide contain one or more diamines selected from the group consisting of alkylenediamines having 2 to 6 carbon atoms and m-xylylenediamine. Among these fatty acid diamides, the use of ethylene bis-12-hydroxystearic acid diamide, 1,4-butane bis-12-hydroxystearic acid diamide, hexamethylene bis-12-hydroxystearic acid diamide, or the like as the organic solid fine particles (B) can impart particularly excellent anti-spreading properties to water-based paints containing the surface conditioner of the present invention.

[0068] The urea is a polymer, oligomer, diurea, or monourea having a urea bond obtained by reacting an isocyanate compound with an amine compound. As the isocyanate compound and the amine compound, one or more compounds described below can be arbitrarily selected and used.

[0069] Examples of isocyanate compounds that can be used include aromatic monoisocyanates, aliphatic monoisocyanates, alicyclic monoisocyanates, compounds in which these monoisocyanates have been made nonvolatile and have reduced toxicity, aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, compounds in which these diisocyanates have been made nonvolatile and have reduced toxicity, adducts of these diisocyanates such as biuret, uretdione, isocyanurate, and allophanate, and relatively low-molecular-weight urethane prepolymers. Examples of aromatic diisocyanates include tolylene diisocyanate (TDI), 4,4'-diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), and m-xylylene diisocyanate (MXDI). Examples of aliphatic diisocyanates include hexamethylene diisocyanate (HDI). Examples of alicyclic diisocyanates include isophorone diisocyanate (IPDI) and hydrogenated MDI. Commercially available polyisocyanates may also be used. Examples of commercially available polyisocyanates include Aquanate 130, Aquanate 140, Aquanate 200, and Aquanate 210 (manufactured by Tosoh Corporation), Bayhydur 304, Bayhydur XP-2655, Bayhydur 401-70, and Bayhydur 3100 (manufactured by Sumika Covestro Urethane Co., Ltd.), Burnock DNW-5000, Burnock DNW-5500, and Burnock DNW-6000 (manufactured by DIC Corporation), and Resamine D-1063 and Resamine D-2040 (manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.).

[0070] The amine compounds include monoamines or polyamines.

[0071] Examples of monoamines that can be used include aliphatic monoamines, alicyclic monoamines, aromatic monoamines, and alkanolamines. Examples of aliphatic monoamines include alkyl monoamines and other aliphatic monoamines. Examples of alkyl monoamines include octylamine, dodecylamine, octadecylamine, and octadecenylamine. Examples of alicyclic monoamines include cyclohexylamine. Examples of aromatic monoamines include aniline and toluidine. Examples of alkanolamines that can be used include ethanolamine, 2-amino-2-methyl-1-propanol, and 12-hydroxystearylamine.

[0072] Examples of polyamines that can be used include aliphatic polyamines, alicyclic polyamines, and aromatic polyamines. Examples of aliphatic polyamines include alkylene polyamines, polyalkylene polyamines, and other aliphatic polyamines. Examples of alkylene polyamines include diaminomethane (methylenediamine), 1,2-diaminoethane, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, and 1,10-diaminodecane. Examples of polyalkylene polyamines include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, and hexamethylenetetramine. Other aliphatic polyamines include, for example, tetra(aminomethyl)methane, tetrakis(2-aminoethylaminomethyl)methane, 1,3-bis(2'-aminoethylamino)propane, triethylene-bis(trimethylene)hexamine, bis(3-aminoethyl)amine, bishexamethylenetriamine, polyethyleneimine, etc. Alicyclic polyamines include, for example, 1,4-cyclohexanediamine, 4,4'-methylenebiscyclohexylamine, 4,4'-isopropylidenebiscyclohexylamine, norbornadiamine, bis(aminomethyl)cyclohexane, diaminodicyclohexylmethane, isophoronediamine, menthenediamine (MDA), etc.Examples of aromatic polyamines include bis(cyanoethyl)diethylenetriamine, o-xylylenediamine, m-xylylenediamine, p-xylylenediamine, phenylenediamine, naphthylenediamine, diaminodiphenylmethane, diaminodiethylphenylmethane, 2,2-bis(4-aminophenyl)propane, 4,4'-diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfone, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 2,4'-diaminobiphenyl, 2,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, bis(aminomethyl)naphthalene, and bis(aminoethyl)naphthalene.

[0073] Oxidized polyethylene is a wax obtained by oxidizing polyethylene and introducing polar groups. Acid-modified polyethylene and acid-modified polypropylene are obtained by graft-modifying polyethylene and polypropylene, respectively, with unsaturated carboxylic acid or its anhydride. Ethylene-vinyl acetate copolymer and ethylene-(meth)acrylic acid copolymer are copolymers of ethylene with polymerizable monomers such as vinyl acetate and (meth)acrylic acid.

[0074] Hydrogenated castor oil (also called "hardened castor oil") is a triglyceride of saturated fatty acids obtained by hydrogenating castor oil. Commercially available hydrogenated castor oils can be used, and examples of such products include C-Wax (manufactured by Kokura Synthetic Industries, Ltd.), Kaowax 85P (manufactured by Kao Corporation), Castor Hydrogenated Oil A (manufactured by Ito Oil Mills, Ltd.), and Castor Hydrogenated Oil (manufactured by Yamakei Sangyo Co., Ltd.).

[0075] In addition to the above-mentioned examples, the organic solid fine particles (B) according to the present invention may also be, for example, polyalkyl(meth)acrylate, copolymers of dibasic acid esters, copolymers of alkyl(meth)acrylates and fatty acid vinyl esters (provided that they are in a solid state in a surface conditioner at 25°C (i.e., do not belong to the polymer (A))), etc.

[0076] Of the specific examples given above, in order to enhance the defoaming property and the anti-spreading property, it is preferable to use ethylene bis 12-hydroxystearic acid diamide, 1,4-butane bis 12-hydroxystearic acid diamide, hexamethylene bis 12-hydroxystearic acid diamide, polyethylene oxide, etc.

[0077] <Content> The content of the above-mentioned organic solid fine particles (B) is preferably 0.1% by mass to 10% by mass, when the total mass of all components in the surface conditioner is taken as 100% by mass. By setting the content of the organic solid fine particles (B) to 0.1% by mass to 10% by mass, sufficient defoaming properties and anti-spreading properties can be exhibited. In order to further improve the appearance of the coating film obtained from the aqueous coating composition to which the surface conditioner has been added, it is more preferable that the content of the organic solid fine particles (B) be 1% by mass to 5% by mass.

[0078] (Organic Medium (C)) The organic medium (C) according to the present invention is a component that exerts defoaming and anti-spreading properties together with the above-mentioned polymer (A), and is a component that is added to enhance the diffusibility of the surface conditioner in the foam film.

[0079] <Fluidity> As the organic medium (C), a medium other than water that is liquid at 25°C can be used. Furthermore, the organic medium (C) is selected from those having 0 to 2 repeating units. That is, the organic medium (C) is a compound having no repeating units or a derivative thereof, or a compound having one or two repeating units or a derivative thereof. The use of such a medium can enhance the diffusibility of the surface conditioner of the present invention in the foam film.

[0080] <Specific Examples> As the organic medium (C), for example, one or more selected from the group consisting of hydrocarbon oils, alcohols, glycol ethers, glycol esters, and polyhydric alcohol fatty acid esters (none of which are included in the polymer (A)) can be suitably used.

[0081] Examples of hydrocarbon oils include those represented by the general formula C ｎ H ２ｎ＋２ n-paraffins and isoparaffins represented by the formula: ｎ H２ｎ One or more cycloparaffins represented by the following formula (I) can be used:

[0082] The above general formula C ｎ H ２ｎ＋２ Examples of n-paraffins represented by the formula (1) include n-hexane, n-heptane, n-octane, n-decane, n-dodecane, and liquid paraffin. Furthermore, commercially available n-paraffin-based mixed solvents can also be used. Commercially available n-paraffin-based mixed solvents include, for example, No. 0 Solvent L (ENEOS Corporation). One or more of these can be arbitrarily selected and used.

[0083] The above general formula C ｎ H ２ｎ＋２ Examples of isoparaffins represented by the formula (I) include isohexane, isooctane, isododecane, isohexadecane, etc. Furthermore, commercially available isoparaffin-based mixed solvents can also be used. Commercially available isoparaffin-based mixed solvents include, for example, IP Solvent and Merveille 30 (both manufactured by Idemitsu Kosan Co., Ltd.), Shellsol T series (manufactured by Shell Chemicals), and Isopar series (manufactured by ExxonMobil Corporation). One or more of these can be arbitrarily selected and used.

[0084] The above general formula C ｎ H ２ｎ As an example of the cycloparaffin represented by the formula (1), commercially available naphthenic solvents can be used. Commercially available naphthenic solvents include, for example, methylcyclohexane, ethylcyclohexane, Swaclean 150 (also known as a mixture of C9 and C10 alkylcyclohexanes) (all manufactured by Maruzen Petrochemical Co., Ltd.), the Naphtesol series, and the Cactus Solvent series (all manufactured by ENEOS Corporation). One or more of these can be arbitrarily selected and used.

[0085] The organic medium (C) is a compound represented by the general formula C ｎ H ２ｎ＋２ n-paraffins and isoparaffins represented by the formula: ｎ H ２ｎAlternatively, a commercially available solvent may be used that is a mixture of at least two or more cycloparaffins represented by the formula (I) above. Examples of such solvents include Naphtesol M (naphthene / isoparaffin / n-paraffin=70% or more / 5-10% / 15% or less, trade name of ENEOS Corporation), Isozole 300 (trade name of ENEOS Corporation), Isozole 400 (trade name of ENEOS Corporation), Exxol D80 (a mixed solvent of paraffin and cycloparaffin, trade name of Exxon Mobil Corporation), Exxol D110 (a mixed solvent of paraffin and cycloparaffin, trade name of Exxon Mobil Corporation), Exxol D130 (a mixed solvent of paraffin and cycloparaffin, trade name of Exxon Mobil Corporation), and Exxol D160 (a mixed solvent of paraffin and cycloparaffin, trade name of Exxon Mobil Corporation). One or more of these solvents may be arbitrarily selected and used.

[0086] Examples of alcohols that can be used include ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, 2-ethylhexanol, isostearyl alcohol, oleyl alcohol, and Texanol. Examples of glycol ethers that can be used include butyl glycol, 2-ethylhexyl glycol, methyl diglycol, dimethyl diglycol, methyl propylene glycol, n-propyl propylene glycol, butyl propylene glycol, methyl dipropylene glycol, propyl dipropylene glycol, and butyl dipropylene glycol. Examples of glycol esters that can be used include propylene glycol monomethyl ether acetate and dipropylene glycol monomethyl ether acetate. Examples of polyhydric alcohol fatty acid esters that can be used include glycerin fatty acid esters, sorbitan fatty acid esters, trimethylolpropane fatty acid esters, and sucrose fatty acid esters.

[0087] Furthermore, as the organic medium (C), in addition to those mentioned above, aromatic solvents such as xylene and toluene, ketone-based solvents such as methyl isobutyl ketone (MIBK), methyl ethyl ketone (MEK), and methyl amyl ketone (MAK: also referred to as 2-heptanone), ether-based solvents such as cyclopentyl methyl ether, acetates, ester-based solvents such as ethyl 3-ethoxypropionate, amide-based solvents such as dimethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, and 3-butoxy-N,N-dimethylpropanamide, oils and fats, and the like may be used.

[0088] <Content> The organic medium (C) described above does not necessarily have to be included in the surface conditioner of the present invention, but when the organic medium (C) is included, its content is preferably 0.5% by mass to 95% by mass, where the total mass of all components in the surface conditioner is 100% by mass. By setting the content of the organic medium (C) to 0.5% by mass to 95% by mass, sufficient defoaming properties and anti-spreading properties can be exhibited. In order to further improve the defoaming properties and anti-spreading properties, it is even more preferable that the content of the organic medium (C) be 5% by mass to 80% by mass.

[0089] (Other Optional Components) The surface conditioner of the present invention may contain components other than the silicone compound and other than the components listed above for the purpose of imparting other functions, as long as the characteristics of the present invention are not impaired. For example, solvents, surfactants, amphiphilic compounds, etc., or paint additives other than the surface conditioner may be added for the purpose of uniformly dissolving or dispersing the above-mentioned components (A) to (C), or improving the leveling properties and uniformity of the paint to which the surface conditioner has been added. Specific examples include water, nonionic surfactants, anionic surfactants, cationic surfactants, amphoteric surfactants, leveling agents, dispersants, etc. (provided that these are not included in the above polymer (A), organic solid fine particles (B), or organic medium (C)).

[0090] (Components not included in the surface conditioner of the present invention) The surface conditioner of the present invention preferably does not contain a silicone compound (a synthetic polymer having a main skeleton formed by siloxane bonds). If a silicone compound is contained in the surface conditioner of the present invention, bleeding of the silicone component onto the coating film surface may cause repellency or inhibit overcoatability. Thus, if a silicone compound is contained in the surface conditioner of the present invention, it may adversely affect the appearance of a coating film applied using a water-based paint containing the surface conditioner. Therefore, a preferred embodiment of the surface conditioner of the present invention does not contain a silicone compound.

[0091] (Form of Surface Conditioner) Specific examples of the form of the surface conditioner according to the present invention include a suspension in which organic solid fine particles (B) are suspended, a form in which an oily suspension is dispersed in a medium mainly composed of water (O(suspension) / W type emulsion), a form in which water-based droplets are dispersed in an oily suspension (W / O(suspension) type emulsion), and a form in which the above-mentioned W / O(suspension) type emulsion is further dispersed in a medium mainly composed of water (W / O(suspension) / W type emulsion).

[0092] (Method for producing surface conditioner) The method for producing a surface conditioner containing the above-mentioned components is not particularly limited, but in order to facilitate the production of a uniformly dispersed surface conditioner and to exhibit excellent defoaming and anti-spreading properties, a method is preferred in which a pre-dispersion of organic solid fine particles (B) (hereinafter referred to as "pre-dispersion of fine particles") is prepared in advance and added to a mixture of the components. The pre-dispersion of fine particles is preferably added while stirring with a disperser or the like. The stirring speed and stirring temperature may be appropriately set depending on the dispersion state of the organic solid fine particles (B), etc. The method for producing the pre-dispersion of fine particles is not particularly limited, and it can be produced by a method known to those skilled in the art. Known examples of such methods include a method in which an organic solid (B') to be made into fine particles for the organic solid fine particles (B) is melted at a predetermined temperature, and the molten liquid is poured into a container containing a polymer (A) and / or an organic medium (C), thereby precipitating the organic solid fine particles (B) in the polymer (A) and / or the organic medium (C) while cooling; a method in which a container containing the organic solid (B'), the polymer (A) and / or the organic medium (C) is melted at a predetermined temperature, and the polymer (A) and / or the organic medium (C) is poured into the molten liquid, thereby precipitating the organic solid fine particles (B) while cooling; and a method in which organic solid fine particles (B), which have been adjusted to a predetermined particle size in advance, are suspended in the polymer (A) and / or the organic medium (C) and then heated.

[0093] (Uses of Surface Conditioner) The surface conditioner of the present invention is suitable for any application, as long as it is added to a water-based paint. However, it is particularly suitable for applications requiring high appearance and for multi-layer coating systems. For example, the surface conditioner of the present invention can provide sufficient defoaming properties during the production, application, and drying of water-based basecoats for automobiles, water-based primer coats for automobiles, water-based paints for luxury furniture, floor paints, interior and exterior paints for buildings, anti-corrosion paints, and home appliances, and can prevent the occurrence of coating defects such as pores during the baking process. In particular, it can effectively prevent pores from occurring when forming multi-layer coatings by wet-on-wet coating. The surface conditioner of the present invention can also be used effectively in applications such as when using paint raw materials that are difficult to disperse in water, or when circulating the paint to prevent the sedimentation and separation of paint components. As described above, the surface conditioner of the present invention has excellent defoaming properties, pore prevention properties, and topcoatability, making it particularly suitable for use as a defoamer or pore prevention agent for water-based paints. That is, the surface conditioner of the present invention is preferably a defoaming agent or an anti-flocculant.

[0094] (Mechanism of Effect) The mechanism by which defoaming droplets and hydrophobic microparticles defoam is well known to those skilled in the art. It can be explained, for example, as follows: When the defoaming droplets or hydrophobic microparticles penetrate into the foam film and the foam film thickness decreases as the water drains from the foam film, the defoaming components contained in the defoaming droplets or hydrophobic microparticles penetrate the foam film. Next, because the penetrated defoaming components are highly hydrophobic, the water breaks down in an attempt to avoid the defoaming components.

[0095] The mechanism by which bubbles form is thought to be as follows: Air bubbles are trapped in the uncured paint film during painting, and during the baking and curing process, volatile solvents in the paint penetrate into the bubbles, increasing their diameter until they eventually grow to a diameter equal to or greater than the film thickness. As a result, air bubbles that do not break and remain in the cured paint film, as well as traces of bubbles that remain in the cured paint film after they have broken, become paint film defects known as "bubbles." Therefore, the size of the bubbles is proportional to the film thickness, and the thicker the film, the larger the bubbles.

[0096] To prevent the occurrence of such bubbles, when a water-based paint is used for coating, it is necessary to break down the entrained bubbles as much as possible during setting, preheating, and baking. However, during setting and preheating, the paint system is in a state of phase transition from an aqueous system to a non-aqueous system, and to break down the entrained bubbles during this phase transition, a polymer with an appropriate range of polarity (SP value) and weight-average molecular weight is required.

[0097] Furthermore, when forming a single-layer coating, bubble-breaking effects can be expected during the setting, preheating, and baking processes. However, when forming a multi-layer coating using the wet-on-wet method, the paint for the upper layer coating is applied while the lower layer coating is still uncured, and the multiple uncured coating layers are simultaneously baked and cured. Therefore, it is necessary to completely remove any trapped bubbles during setting and preheating. Therefore, conventional surface conditioners (antifoaming agents, anti-fouling agents) containing only polymer components have not been able to achieve sufficient bubble-breaking effects. In contrast, using low-polarity polymers such as silicone compounds to enhance the bubble-breaking effect has high bubble-breaking properties, but inhibits topcoatability, limiting their use in forming multi-layer coatings.

[0098] Therefore, the surface conditioner of the present invention has the above-mentioned polymer (A) and organic solid fine particles (B) as essential components. Such a surface conditioner has an excellent effect on breaking down trapped bubbles even during the phase transition of the paint system, and can remove trapped bubbles only during setting and preheating when forming a multi-layer coating film in a wet-on-wet manner. It is believed that the use of a polymer (A) having a SP value and weight-average molecular weight within a predetermined range, and the use of organic solid fine particles (B) with high affinity with this polymer (A), significantly improves the bubble-breaking effect of the polymer component. In order to enhance the affinity of the organic solid fine particles with the polymer component, it is more desirable that the shape of the organic solid fine particles (B) has specific characteristics. Specifically, it is believed that the affinity with the polymer (A) is particularly excellent when the organic solid fine particles (B) are (1) porous fine particles, (2) fine particles with an uneven surface, or (3) clusters of microcrystals with a specific aspect ratio.

[0099] [Water-based coating composition] The water-based coating composition of the present invention contains the above-mentioned surface conditioner and water-based resin as essential components. The water-based coating composition of the present invention may further contain other coating raw materials as optional components, such as a diluting solvent, pigment, dispersant, lubricant, emulsifier, viscosity modifier, film-forming aid, and pH adjuster.

[0100] (Surface Conditioner Content) The content of the surface conditioner of the present invention varies depending on the type of aqueous resin used as the binder in the aqueous coating composition, the pigment formulation, and other factors, but is typically preferably 0.1% to 5% by mass, and more preferably 0.5% to 2% by mass, relative to the aqueous coating composition. If the surface conditioner content is less than 0.1% by mass, the effects of adding the surface conditioner of the present invention, such as antifoaming and anti-fizzing properties, may not be fully exhibited. On the other hand, if the surface conditioner content exceeds 5% by mass, adverse effects such as poor interlayer adhesion when coating multiple coats of paint, uneven coating of the topcoat (upper layer) coating, or poor water resistance of the coating film after drying may occur, which is undesirable.

[0101] (Water-based Resin) The water-based resin contained as a binder in the water-based coating composition of the present invention is a resin component dispersed in a water-based medium. Examples of the resin component include acrylic resins, acrylic-silicone resins, alkyd resins, polyester resins, urethane resins, epoxy resins, silicone resins, and fluororesins. The form of the water-based resin can be divided into water-soluble, colloidal dispersion, and emulsion depending on the dispersion form, and any form is applicable. These resins may be, for example, heat-curable, ultraviolet-curable, electron beam-curable, oxidation-curable, photocation-curable, peroxide-curable, or curable by a chemical reaction in the presence or absence of a catalyst. They may also be resins with a high glass transition point that form a coating without a chemical reaction simply by volatilizing the dilution medium. Examples of curing agents include amino resins, melamine resins, isocyanate compounds, blocked isocyanate compounds, silane coupling agents, and epoxy compounds.

[0102] (Pigments) Examples of pigments include extender pigments such as calcium carbonate (heavy calcium carbonate (GCC), precipitated calcium carbonate (PCC), etc.), barium sulfate, silicon dioxide, aluminum hydroxide, talc, mica, organic fibers, and glass powder; color pigments such as titanium dioxide, carbon black, yellow lead, cadmium yellow, ochre, titanium yellow, zinc chromate, red iron oxide, aluminosilicate, quinacridone, phthalocyanine, anthroquinone, diketopyrrolopyrrole, benzimidazolone, and isoindolinone; and lustrous pigments such as metallic pigments and effect pigments (pearl pigments) in which metallic pigments are coated with metal oxides such as titanium oxide. Examples of metallic pigments include aluminum flakes, copper flakes, glass flakes, artificial alumina crystals (commercially available products include, for example, Xiralic (registered trademark) manufactured by Merck), micaceous iron oxide, and mica.

[0103] (Other Additives) The aqueous coating composition of the present invention may contain other substances, such as dispersants, lubricants, emulsifiers, viscosity modifiers, dehydrating agents (e.g., silane coupling agents), adhesion improvers, surfactants, curing catalysts, film-forming aids, driers, antifouling agents, sensitizers, antioxidants, light stabilizers, ultraviolet absorbers, water-resistant agents, antiseptic and antifungal agents, leveling agents, flame retardants, antistatic agents, release agents, deodorizers, pH adjusters, fragrances, and other additives, provided that the properties of the aqueous coating composition of the present invention and the objects of the present invention are not impaired.

[0104] Here, surfactants are typically used as dispersants for dispersing pigments in paints, wetting agents for improving the wetting and smoothness of pigments, emulsifiers for emulsifying non-aqueous resins, and viscosity modifiers for controlling the fluidity of paints, but these surfactants generate unnecessary bubbles during the manufacturing process and application of aqueous paints. However, by incorporating the surface conditioner of the present invention into an aqueous paint composition, it is possible to suppress the generation and persistence of bubbles and prevent the generation of bubbles when forming a multi-layer paint film by wet-on-wet coating. As a result, a paint film with excellent paint film appearance can be formed, and topcoatability is not impaired.

[0105] (Method for producing aqueous coating composition) The aqueous coating composition of the present invention can be produced in accordance with known methods for producing aqueous coatings. For example, the components other than the surface conditioner and pigment described above are mixed with stirring in a medium mainly composed of water such as ion-exchanged water, and then the pH is adjusted as necessary to produce a clear coating. The surface conditioner and pigment are added to this clear coating and dispersed in the clear coating, thereby producing an aqueous coating composition.

[0106] The timing of adding the surface conditioner of the present invention to the water-based paint may be during the process of kneading the pigment as described above, or after the water-based paint is produced. It is also possible to prepare a masterbatch and add it. Equipment commonly used in the production of water-based paints can be used to disperse the surface conditioner and pigment. The stirring speed and stirring time conditions for dispersing the surface conditioner and pigment are not particularly limited, and can be set appropriately while checking the dispersion state of the surface conditioner and pigment.

[0107] (Uses of Water-Based Coating Composition) The water-based coating composition of the present invention is suitable for use in applications requiring high appearance or in coating systems using multi-layer coatings (particularly when multi-layer coatings are formed by wet-on-wet coating). Examples of such applications include coating automotive materials, coating high-end furniture materials, floor paints, architectural interior and exterior paints, anticorrosion paints, and coating home appliances. The water-based coating composition of the present invention can also be used suitably in applications such as when using coating raw materials that are difficult to disperse in water, or when circulating the paint to prevent the sedimentation and separation of the components in the paint.

[0108] [Article] The article of the present invention is a substrate as a coating object, the surface of which is coated with a coating agent containing the above-mentioned surface conditioner. That is, the article of the present invention comprises a substrate and a coating film obtained by coating the surface of the substrate with a coating agent.

[0109] (Substrate) The substrate of the article according to the present invention is not particularly limited, and examples thereof include substrates made of metal, plastic, wood, rubber, glass, stone, cement, mortar, paper, nonwoven fabric, cloth, and ceramics.

[0110] (Coating film) The coating film possessed by the article of the present invention is, for example, obtained by applying the above-mentioned aqueous coating composition to the substrate and then curing it. The coating film formed on the surface of the substrate may be a single layer, or may be a laminate of multiple coating films (multi-layer coating film). Since the aqueous coating composition containing the surface conditioner of the present invention has excellent defoaming properties and anti-flake properties, even when the aqueous coating composition is used for applications requiring extremely high levels of appearance and recoatability, a satisfactory coating film appearance can be obtained without impairing recoatability.

[0111] (Coating Agent) The coating agent of the present invention used to coat the substrate may be, for example, the water-based paint composition described above.

[0112] (Method for manufacturing an article) The article of the present invention can be manufactured by applying a coating agent, such as the aqueous paint composition of the present invention, to the above-mentioned substrate, followed by drying and curing. The method for applying the coating agent is not particularly limited, and examples thereof include spray coating, roll coating, brush coating, curtain coating, bar coating, doctor blade coating, slit coating, dip coating, and flow coating. The method for curing the coating agent is not particularly limited, and examples thereof include room temperature curing, heat curing, and ultraviolet curing.

[0113] Furthermore, when a multi-layer coating film (multi-layer coating film) is formed on the article of the present invention, for example, it includes a first coating film obtained by applying the aqueous coating composition of the present invention to a substrate, and a second coating film laminated on all or part of the surface of the first coating film. The second coating film used to form the second coating film may be the same as the first coating film used for the first coating film, or a different one may be used. Furthermore, when forming a multi-layer coating film, the first coating film may be completely dried or cured before being overcoated with the second coating film, or the first coating film may be overcoated in an incompletely dried or cured state to the extent that it is not disturbed by the second coating film. Because the aqueous coating composition containing the surface conditioner of the present invention has excellent overcoatability, even when the aqueous coating composition is used for applications requiring extremely high levels of appearance and overcoatability, the interlayer adhesion between the coating film obtained from the aqueous coating composition of the present invention and the coating film overcoated on the first coating film is excellent.

[0114] When forming a multilayer coating film on the article of the present invention, the multilayer coating film is formed, for example, by coating all or part of the surface of a coating film obtained by curing a first coating material to which the surface conditioner of the present invention has been added with a second coating material. Alternatively, the second coating material may be applied by a wet-on-wet method without curing the first water-based coating material to which the surface conditioner of the present invention has been added, and then the first coating material and the second coating material may be cured simultaneously.

[0115] The method of applying and curing the second coating material is not particularly limited, and the same methods as those described above can be used.

[0116] (Uses of Articles) The articles of the present invention are suitable for use in applications requiring high appearance or in coating systems using multi-layer coating films (particularly when multi-layer coating films are formed by a wet-on-wet method), such as automobile parts, high-end furniture, and home appliances.

[0117] [Method for forming a multilayer coating film] The method for forming a multilayer coating film according to the present invention is a method for forming at least two or more coating layers by successively applying at least two or more water-based coating materials wet-on-wet to the surface of an object to be coated, and then simultaneously heat-curing the water-based coating materials applied to the object to be coated. In this case, at least one of the two or more water-based coating materials is a water-based coating composition containing the above-mentioned surface conditioner of the present invention.

[0118] The substrate for the article according to the present invention described above can be used as the object to be coated.

[0119] The two or more water-based paints may be, for example, a first water-based paint containing the above-mentioned color pigment (corresponding to the "first paint" in this specification), a second water-based paint containing the above-mentioned lustrous pigment (corresponding to the "second paint" in this specification), and a clear paint. In this case, the water-based paint composition containing the above-mentioned surface conditioner of the present invention is used as at least one of the first water-based paint and the second water-based paint (i.e., only the first water-based paint, only the second water-based paint, or both the first water-based paint and the second water-based paint).

[0120] The method for applying the water-based paint to the substrate is not particularly limited, and examples thereof include spray coating, roll coating, brush coating, curtain coating, bar coating, doctor blade coating, slit coating, dip coating, and flow coating. The curing method for the water-based paint is not particularly limited, and examples thereof include room temperature curing, heat curing, and ultraviolet curing. Furthermore, when applying two or more water-based paints wet-on-wet, it is preferable to apply a first water-based paint containing the surface conditioner of the present invention, and then, as necessary, natural drying, air blowing, or preheat drying to remove unnecessary solvent (volatile components such as water and organic solvents) without curing the first water-based paint, and then apply a second water-based paint. Preheat drying is particularly suitable as a drying method for the first water-based paint.

[0121] While the preferred embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments. In other words, it is understood that other embodiments or various modifications that can be conceived by a person skilled in the art within the scope of the invention described in the claims also fall within the technical scope of the present invention.

[0122] Specific examples of the present invention include the following: (1) A surface conditioner for water-based paints, comprising: a polymer (A) having an SP value of 6 to 12, a weight-average molecular weight of 200 to 1,000,000, and at least three repeating units; and organic solid fine particles (B) that are in a solid state in the surface conditioner at 25° C. (2) The surface conditioner according to (1), wherein the polymer (A) is one or more polymers selected from the group consisting of polyvinyl alkyl ether, polybutadiene, polybutene, polyalphaolefin, polyalkyl(meth)acrylate, copolymers of dibasic acid esters, polyfatty acid vinyl esters, polyalkylene glycols and derivatives thereof, polyamides, polyglycerin fatty acid esters, and polyesters. (3) The surface conditioner according to (1) or (2), wherein the organic solid fine particles (B) are one or more solid fine particles selected from the group consisting of amide, urea, polyethylene, polyethylene oxide, acid-modified polyethylene, ethylene-vinyl acetate copolymer, ethylene (meth)acrylic acid copolymer, polypropylene, acid-modified polypropylene, and hydrogenated castor oil. (4) The surface conditioner according to (3), wherein the amide is a fatty acid diamide obtained by reacting a fatty acid selected from the group consisting of alkyl fatty acids and hydroxy fatty acids, containing at least one hydroxy fatty acid, with a diamine containing one or more diamines selected from the group consisting of alkylenediamines having 2 to 6 carbon atoms and m-xylylenediamine. (5) The surface conditioner according to any one of (1) to (4), wherein the crystal aspect ratio of the organic solid fine particles (B) is 1.1 to 100. (6) The surface conditioner according to any one of (1) to (5), characterized in that the mode diameter of the organic solid fine particles (B) is 0.1 to 150 μm. (7) The surface conditioner according to any one of (1) to (6), characterized in that it further contains an organic medium (C) other than water that is liquid at 25° C., and the organic medium (C) has 0 to 2 repeating units.(8) The surface conditioner according to (7), characterized in that the organic medium (C) is one or more selected from the group consisting of hydrocarbon oils, alcohols, glycol ethers, glycol esters, and polyhydric alcohol fatty acid esters. (9) A water-based coating composition comprising the surface conditioner according to any one of (1) to (8) and a water-based resin. (10) An article coated with a coating agent comprising the surface conditioner according to any one of (1) to (8). (11) A method for forming a multilayer coating film, comprising a film-forming step of successively applying at least two or more water-based coating materials to the surface of an object to be coated in a wet-on-wet manner, and then simultaneously heat-curing the water-based coating materials applied to the object to form at least two or more coating layers, wherein at least one of the two or more water-based coating materials contains the surface conditioner according to any one of (1) to (8). (12) The method for forming a multilayer coating film according to (11), characterized in that the two or more types of water-based coating materials are a first water-based coating material containing a color pigment and a second water-based coating material containing a lustrous pigment, at least one of the first water-based coating material and the second water-based coating material contains the surface conditioner, and in the film-forming step, the first water-based coating material, the second water-based coating material and the clear coating material are applied successively wet-on-wet, and then the first water-based coating material, the second water-based coating material and the clear coating material are simultaneously heat-cured to form a first water-based resin coating film, a second water-based resin coating film and a clear coating film laminated in that order from the surface of the substrate.

[0123] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. In the examples, "%" and "parts" refer to "% by mass" and "parts by mass" unless otherwise specified.

[0124] [Preparation of Surface Conditioner Samples] Surface conditioner samples E1 to E33 and C1 to C9 were prepared as follows.

[0125] (Synthesis and Preparation of Polymers) In the present examples and comparative examples, the raw materials listed in Table 1 below were used as polymer components containing polymer (A). Note that raw materials listed as "A" as the component type in Table 1 are examples of polymer (A) of the present invention, and raw materials listed as "non-A component" are raw materials that do not correspond to polymer (A) of the present invention. Below, synthesis methods for raw materials listed in Table 1 as "Source of Acquisition" as "Manufacturing Method Described in This Application" are shown.

[0126] <Synthesis of Polymer 1> 95.3 parts of butyl acetate was charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. Thereafter, the internal temperature was raised to the reflux state of the butyl acetate while stirring under a nitrogen gas stream. A mixture consisting of 281.3 parts of vinyl laurate, 93.8 parts of Blemmer AME-400 (methoxypolyethylene glycol acrylate manufactured by NOF Corporation), and 18.8 parts of a 50% solution of tertiary-butylperoxy-2-ethylhexanoate was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at a reflux state, the dropping solution was uniformly added dropwise over 120 minutes. After completion of the dropping, the reaction temperature was maintained at a reflux state for 40 minutes, allowing the reaction to proceed. After completion of the reaction, the solvent was removed using an evaporator, yielding Polymer 1. The weight-average molecular weight of the synthesized polymer was 14,700 (SP value: 9.3).

[0127] <Synthesis of Polymer 2> 95.0 parts of butyl acetate and 159.4 parts of dibutyl fumarate were charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to a reflux state for butyl acetate while stirring under a nitrogen gas stream. A mixture consisting of 28.1 parts of dibutyl fumarate, 187.5 parts of ethyl acrylate, 30.0 parts of a 55% solution of 2,2-di(tert-amylperoxy)butane, and 7.5 parts of 2-ethylhexyl thioglycolate was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at a reflux state, the dropping solution was added dropwise uniformly over 120 minutes. After completion of the dropping, the reaction temperature was maintained at a reflux state for 120 minutes, and the reaction was carried out. After completion of the reaction, the solvent was removed using an evaporator, and Polymer 2 was obtained. The weight average molecular weight of the synthesized polymer was 3,500 (SP value: 10.1).

[0128] <Synthesis of Polymer 3> 108.0 parts of butyl acetate were charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to the reflux state of the butyl acetate while stirring under a nitrogen gas stream. A mixture consisting of 375.0 parts of 2-ethylhexyl acrylate and 17.2 parts of a 55% solution of 2,2-di(tert-amylperoxy)butane was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at a reflux state, the dropping solution was uniformly added dropwise over 120 minutes. After completion of the dropping, the reaction temperature was maintained at reflux for 60 minutes to allow the reaction to proceed. After completion of the reaction, the solvent was removed using an evaporator to obtain Polymer 3. The weight-average molecular weight of the synthesized polymer was 7,800 (SP value: 9.2).

[0129] <Synthesis of Polymer 4> 197.5 parts of Merveille 30 (an isoparaffinic solvent manufactured by Idemitsu Kosan Co., Ltd.) were charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to 95°C while stirring under a nitrogen gas stream. A mixture consisting of 250.0 parts of lauryl methacrylate, 49.4 parts of Merveille 30, and 3.1 parts of a 40% solution of tert-butylperoxy-2-ethylhexanoate was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at 95°C, the dropping solution was added dropwise uniformly over 75 minutes. After completion of the dropwise addition, the reaction temperature was maintained at 95°C for 60 minutes, after which 0.7 parts of a 40% solution of tert-butylperoxy-2-ethylhexanoate was added and the mixture was maintained at 95°C for 45 minutes. The internal temperature of the reaction vessel was then raised to 100°C, and the reaction was carried out for 30 minutes. After the reaction was completed, the heating residue was adjusted to 50% using Merveille 30, yielding Polymer 4. The weight-average molecular weight of the synthesized polymer was 178,900 (SP value: 9.0).

[0130] <Synthesis of Polymer 5> 150.0 parts of toluene were charged into a 1000 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to 35°C while stirring under a nitrogen gas stream. Next, a mixture of 0.30 parts of boron trifluoride diethyl ether complex and 2.7 parts of diethyl ether was added to the reaction vessel. Then, 300.0 parts of ethyl vinyl ether was charged into the dropping funnel as a dropping solution, and the dropping solution was uniformly added dropwise over 120 minutes while maintaining the internal temperature of the reaction vessel at 35°C. After completion of the dropping, the reaction temperature was maintained at 35°C for 30 minutes, and the reaction was continued. Then, 15.00 parts of ethanol was added to the reaction vessel. After completion of the reaction, the solvent was removed using an evaporator to obtain Polymer 5. The weight-average molecular weight of the synthesized polymer was 4000 (SP value: 8.6).

[0131] <Synthesis of Polymer 6> 221.0 parts of dimer acid and 29.0 parts of hexamethylenediamine were charged into a 500 mL reaction vessel equipped with a stirrer, a water divider, a reflux condenser, a thermometer, and a nitrogen gas inlet tube. The internal temperature was then raised to 150°C while stirring under a nitrogen gas stream, and the reaction was continued for 60 minutes while maintaining the reaction temperature. The internal temperature was then further raised to 175°C, and the reaction was continued for 90 minutes while maintaining the reaction temperature, yielding Polymer 6. The weight-average molecular weight of the synthesized polymer was 5,800 (SP value: 9.6).

[0132] <Synthesis of Polymer 7> 136.6 parts of dimer acid and 13.5 parts of hexamethylenediamine were charged into a 500 mL reaction vessel equipped with a stirrer, a water divider, a reflux condenser, a thermometer, and a nitrogen gas inlet tube. The internal temperature was then raised to 150°C while stirring under a nitrogen gas stream, and the reaction was continued for 60 minutes while maintaining the reaction temperature. The internal temperature was then further raised to 175°C and maintained at this temperature for 90 minutes. 230.0 parts of Newpol (registered trademark) LB-625 (polypropylene glycol monobutyl ether manufactured by Sanyo Chemical Industries, Ltd.) were then charged into the reaction vessel, and the internal temperature was raised to 240°C while stirring. The reaction was continued for 7 hours while maintaining the reaction temperature, yielding Polymer 7. The weight-average molecular weight of the synthesized polymer was 8700 (SP value: 9.0).

[0133] <Synthesis of Polymer 8> 118.2 parts of butyl acetate were charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to the reflux state of the butyl acetate while stirring under a nitrogen gas stream. A mixture consisting of 125.0 parts of vinyl laurate and 6.8 parts of a 55% solution of 2,2-di(tertiary-amylperoxy)butane was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at a reflux state, the dropping solution was uniformly added dropwise over 120 minutes. After completion of the dropping, the reaction temperature was maintained at reflux for 60 minutes to allow the reaction to proceed. After completion of the reaction, the solvent was removed using an evaporator to obtain Polymer 8. The weight-average molecular weight of the synthesized polymer was 8100 (SP value: 9.2).

[0134] <Synthesis of Polymer 9> 188.5 parts of Merveilleux 30 (an isoparaffinic solvent manufactured by Idemitsu Kosan Co., Ltd.) were charged into a 1000 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to 95°C while stirring under a nitrogen gas stream. A mixture consisting of 250.0 parts of lauryl methacrylate, 47.1 parts of Merveilleux 30, and 12.5 parts of a 40% solution of tert-butylperoxy-2-ethylhexanoate was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at 95°C, the dropping solution was added dropwise uniformly over 75 minutes. After completion of the dropwise addition, the reaction temperature was maintained at 95°C for 60 minutes, after which 0.7 parts of a 40% solution of tert-butylperoxy-2-ethylhexanoate was added and the mixture was maintained at 95°C for 45 minutes. Thereafter, the internal temperature of the reaction vessel was raised to 100°C, and the reaction was carried out for 30 minutes. After the reaction was completed, the heating residue was adjusted to 50% using Merveille 30, to obtain Polymer 9. The weight average molecular weight of the synthesized polymer was 74,100 (SP value: 9.0).

[0135] <Synthesis of Polymer 10> 362.5 parts of ethanol and 12.50 parts of dimethyl 2,2'-azobis(isobutyrate) were charged into a 500 mL reaction vessel equipped with a stirrer, reflux condenser, dropping funnel, thermometer, and nitrogen gas inlet tube. The internal temperature was then raised to 70°C while stirring under a nitrogen gas stream. A mixture consisting of 125.0 parts of methacrylic acid and 6.25 parts of 2-ethylhexyl thioglycolate was charged into the dropping funnel as a dropping solution. Next, while maintaining the internal temperature of the reaction vessel at 70°C, the dropping solution was uniformly added dropwise over 120 minutes. After completion of the dropwise addition, the reaction temperature was maintained at 70°C for 180 minutes. After completion of the reaction, the solvent was removed using an evaporator, and the heating residue was adjusted to 50%, yielding Polymer 10. The weight-average molecular weight of the synthesized polymer was 4000 (SP value: 12.5).

[0136] The SP values ​​of the polymers shown in Table 1 were calculated by the Fedors method. Furthermore, when measuring the weight-average molecular weights of the polymers shown in Table 1, HLC-8320GPC (manufactured by Tosoh Corporation) was used as a measuring instrument, and TSKgel GMHxl x 2, TSKgel G2500Hxl, TSKgel G2000Hxl, and TSKgel guard column (all manufactured by Tosoh Corporation) were used as columns, tetrahydrofuran (THF) was used as the mobile phase, the column temperature was 40 ° C., the flow rate was 1 mL / min, and an RI detector was used as the detector. The weight-average molecular weights shown in Table 2 are values ​​calculated based on the molecular weight of standard polystyrene from a chromatograph measured by gel permeation chromatography (GPC).

[0137]

[0138] (Production and Preparation of Solid Fine Particles) In the present examples and comparative examples, the raw materials listed in Table 2 below were used as solid fine particle components containing organic solid fine particles (B). The raw materials listed as "B" as the component type in Table 2 are examples of the organic solid fine particles (B) of the present invention. The methods for producing the raw materials in Table 2 are shown below. Specifically, fine particles OC-1 to OC-17, which are examples of the organic solid fine particles (B), were produced by the methods shown below.

[0139] <OC-1> 2 moles of 12-hydroxystearic acid (12-HSA) and 1 mole of hexamethylenediamine were reacted under a nitrogen gas stream at 190 ° C. for 6 hours, removing the generated water, to obtain diamide (a1) (Step 0). Next, a mixture (particle mixture) of 10 parts of diamide (a1) as a microparticle component and 90 parts of Merveille 30 (an isoparaffinic solvent manufactured by Idemitsu Kosan Co., Ltd.) as an organic medium (D) was heated to 165 ° C. with a heater, and diamide (a1) was heated and dissolved in Merveille 30 to obtain a microparticle solution (Step 1). In addition, 60 parts of Merveille 30 were charged into a 500 mL container, and the microparticle solution was poured into it under stirring, and cooled so that the temperature after mixing was 97.0 ° C. (Step 2). After the mixture into which the microparticle solution was poured was cooled to around 30 ° C., 40 parts of ethanol was added to this mixture and stirred (Step 3). Next, the temperature of the mixture was adjusted to 46.5° C. while stirring was continued, and stirring was continued for 12 minutes to obtain a preliminary dispersion of fine particles OC-1 (Step 4).

[0140] <OC-2> A preliminary dispersion of fine particles OC-2 was obtained in the same manner as OC-1, except that in steps 1 and 2, Newpol LB-625 (polypropylene glycol monobutyl ether manufactured by Sanyo Chemical Industries, Ltd.) was used instead of Merveille 30, and in step 1, the fine particle mixture was heated to 135°C, in step 2, it was cooled so that the temperature after mixing became 42.9°C, in step 3, Newpol LB-625 was used instead of ethanol, and step 4 was not carried out.

[0141] <OC-3> A preliminary dispersion of fine particles OC-3 was obtained in the same manner as for OC-1, except that in step 0, 2 moles of 12-HSA were reacted with 1 mole of ethylenediamine to obtain diamide (a2), in step 1, diamide (a2) was used instead of diamide (a1), and the fine particle mixture was heated to 155°C, in step 2, the mixture was cooled so that the temperature after mixing would be 45.6°C, and in step 4, the temperature of the mixture was adjusted to 45.5°C.

[0142] <OC-4> A preliminary dispersion of fine particles OC-4 was obtained in the same manner as OC-1, except that in step 0, 2 moles of 12-HSA were reacted with 1 mole of 1,4-diaminobutane to obtain diamide (a3), in step 1, diamide (a3) ​​was used instead of diamide (a1), and the fine particle mixture was heated to 160°C, in step 2, the mixture was cooled so that the temperature after mixing became 97.0°C, and in step 4, the temperature of the mixture was adjusted to 42.0°C.

[0143] <OC-5> A preliminary dispersion of fine particles OC-5 was obtained in the same manner as OC-1, except that step 0 was not performed, hydrogenated castor oil was used instead of diamide (a1) in step 1, the fine particle mixture was heated to 95°C, the temperature after mixing was cooled to 53.9°C in step 2, and step 4 was not performed.

[0144] <OC-6> A preliminary dispersion of fine particles OC-6 was obtained by the same method as OC-1, except that step 0 was not carried out, A-C629 (low-density oxidized polyethylene manufactured by Honeywell Japan Co., Ltd.) was used instead of diamide (a1) in step 1, the fine particle mixture was heated to 150°C, 100 parts of Merveilles 30 was charged in step 2, and the temperature after mixing was cooled to 46.7°C, and step 3 and step 4 were not carried out.

[0145] <OC-7> A preliminary dispersion of fine particles OC-7 was obtained in the same manner as OC-1, except that in steps 1 and 2, Buticel (butyl glycol manufactured by KH Neochem Co., Ltd.) was used instead of Merveille 30, and in step 1, the fine particle mixture was heated to 120°C, and in step 2, it was cooled so that the temperature after mixing would be 25.0°C, and in step 3, Buticel was used instead of ethanol, and step 4 was not performed.

[0146] <OC-8> After step 3, instead of step 4, the mixed solution obtained in step 3 was placed in a bottle, heated to 70°C over 24 hours, and maintained at that temperature for 24 hours. Thereafter, a preliminary dispersion of fine particles OC-8 was obtained in the same manner as for OC-1, except that the temperature was lowered to 25°C over 24 hours.

[0147] <OC-9> A preliminary dispersion of fine particles OC-9 was obtained in the same manner as OC-1, except that in steps 1 and 2, DOWANOL (registered trademark) PM (methyl propylene glycol manufactured by Dow-Toray Industries, Inc.) was used instead of MERVEILLE 30, and in step 1, the fine particle mixture was heated to 110°C, in step 2, it was cooled so that the temperature after mixing would be 48.5°C, and in step 4, the temperature of the mixed liquid was adjusted to 50.4°C.

[0148] <OC-10> A preliminary dispersion of fine particles OC-10 was obtained in the same manner as for OC-1, except that in step 0, 2 moles of 12-HSA and 1 mole of m-xylylenediamine were reacted to obtain diamide (a4), in step 1, diamide (a4) was used instead of diamide (a1), and the fine particle mixture was heated to 150°C, in step 2, the mixture was cooled so that the temperature after mixing would be 46.5°C, and in step 4, the temperature of the mixture was adjusted to 47.3°C.

[0149] <OC-11> A preliminary dispersion of fine particles OC-11 was obtained in the same manner as OC-1, except that in steps 1 and 2, 2-ethylhexanol (manufactured by Mitsubishi Chemical Corporation) was used instead of Merveilleux 30, and in step 1, the fine particle mixture was heated to 135°C, in step 2, it was cooled so that the temperature after mixing would be 45.5°C, and in step 4, the temperature of the mixed liquid was adjusted to 62.1°C.

[0150] <OC-12> A preliminary dispersion of fine particles OC-12 was obtained in the same manner as OC-1, except that step 0 was not performed, 2-ethylhexanol (manufactured by Mitsubishi Chemical Corporation) was used instead of Merveille 30 in steps 1 and 2, A-C629 (low-density oxidized polyethylene manufactured by Honeywell Japan, Ltd.) was used instead of diamide (a1), the fine particle mixture was heated to 120°C, 100 parts of 2-ethylhexanol was charged in step 2, and the mixture was cooled so that the temperature after mixing became 35.5°C, and steps 3 and 4 were not performed.

[0151] <OC-13> A preliminary dispersion of fine particles OC-13 was obtained in the same manner as OC-1, except that step 0 was not performed, 2-ethylhexanol (manufactured by Mitsubishi Chemical Corporation) was used instead of Merveille 30 in steps 1 and 2, Ceridust 3620 (polyethylene wax manufactured by Clariant Japan Co., Ltd.) was used instead of diamide (a1), the fine particle mixture was heated to 140°C, 100 parts of 2-ethylhexanol was charged in step 2, and the mixture was cooled so that the temperature after mixing became 32.2°C, and steps 3 and 4 were not performed.

[0152] <OC-14> A preliminary dispersion of fine particles OC-14 was obtained in the same manner as OC-1, except that step 0 was not carried out, Ceridust 3620 (polyethylene wax manufactured by Clariant Japan Co., Ltd.) was used instead of diamide (a1) in step 1, the fine particle mixture was heated to 130°C, 100 parts of Merveilleux 30 was charged in step 2, and the mixture was cooled so that the temperature after mixing became 35.3°C, and step 3 and step 4 were not carried out.

[0153] <OC-15> A preliminary dispersion of fine particles OC-15 was obtained in the same manner as OC-1, except that step 0 was not carried out, A-C405T (ethylene vinyl acetate copolymer manufactured by Honeywell Japan, Ltd.) was used instead of diamide (a1) in step 1, the fine particle mixture was heated to 100°C, 100 parts of Merveilleux 30 was charged in step 2, and the mixture was cooled so that the temperature after mixing became 35.9°C, and step 3 and step 4 were not carried out.

[0154] <OC-16> A preliminary dispersion of fine particles OC-16 was obtained in the same manner as OC-1, except that step 0 was not performed, 2-ethylhexanol (manufactured by Mitsubishi Chemical Corporation) was used instead of Merveille 30 in steps 1 and 2, A-C540 (ethylene acrylic acid copolymer manufactured by Honeywell Japan, Ltd.) was used instead of diamide (a1), the fine particle mixture was heated to 120°C, 100 parts of 2-ethylhexanol was charged in step 2, and the mixture was cooled so that the temperature after mixing would be 33.3°C, and steps 3 and 4 were not performed.

[0155] <OC-17> A preliminary dispersion of fine particles OC-17 was obtained in the same manner as OC-1, except that step 0 was not performed, in step 1, Biscol 660-P (polypropylene wax manufactured by Sanyo Chemical Industries, Ltd.) was used instead of diamide (a1), the fine particle mixture was heated to 120°C, in step 2, 100 parts of Merveilles 30 was charged and the temperature after mixing was cooled to 30.1°C, and step 3 and step 4 were not performed.

[0156] <Measurement of Peak Particle Size> The peak particle sizes of the fine particles OC-1 to OC-17 obtained as described above were measured using a particle size distribution analyzer Microtrac MT-3000EXII / USVR (manufactured by Microtrac) and Merveilleux 30 as a circulating solvent. The peak particle sizes (μm) of the respective organic solid fine particles are shown in Table 2.

[0157] <Aspect Ratio Measurement> The aspect ratios of the fine particles OC-1 to OC-17 obtained as described above were measured as follows: 1) A preliminary dispersion of the fine particles OC-1 to OC-17 was diluted 300 times with xylene, and the fine particles were dispersed in the diluted solution by irradiating with ultrasound for 30 seconds. 2) A drop of the diluted solution obtained in 1) was placed on a copper microgrid (grid pitch 150 μm) with a carbon-reinforced collodion support film on filter paper and allowed to dry naturally. 3) The microgrid carrying the fine particle sample obtained in 2) was fixed to an SEM mount using carbon tape. 4) SEM measurements were performed using an SU3500 (Hitachi High-Technologies Corporation) measuring device, measurement mode: high vacuum / low accelerating voltage, image capture: backscattered electron image, image capture magnification: 2,000x, brightness / contrast: auto, and focus: manual. 5) Image analysis was performed using image analysis software (ImageJ). After brightness / contrast correction and smoothing correction, the image was binarized, and noise, particles at the image boundary, and aggregated particles were removed before particle analysis. 6) When the particles to be measured were composed only of convex shapes, particle analysis was performed, and the aspect ratio (= major axis value / minor axis value) was calculated from the obtained major axis value and minor axis value of each particle. The average of the aspect ratios of 10 or more particles was used as the aspect ratio of the microparticle sample (microparticles OC-1 to OC-17). 7) When the particles to be measured included convex and non-convex shapes, the fiber length was measured using a freehand line tool, and the fiber width at the center of the particle was measured using a straight line tool. The aspect ratio (= fiber length value / fiber width value) was calculated, and the average of the aspect ratios of 10 or more particles was used as the aspect ratio of the sample.

[0158] The "non-convex shape" refers to a particle whose convex hull (the area enclosed by a contractile imaginary curve) has an area twice or more of its actual area. The "convex shape" refers to a particle whose convex hull has an area less than twice of its actual area. The aspect ratios of each organic solid fine particle are shown in Table 2.

[0159]

[0160] (Preparation of Organic Medium) In the present examples and comparative examples, the raw materials listed in Table 3 below were used as the organic medium (C). Note that for some of the raw materials, the boiling points are listed in Table 3.

[0161]

[0162] (Preparation of Surface Conditioner Samples) Surface conditioner samples E1 to E43 and C1 to C11 were prepared by the method described below. Details of the preparation method for each surface conditioner sample are shown below.

[0163] <Surface conditioner sample E1> A 100 mL plastic cup was charged with 35.0 parts of Uniol (registered trademark) TG-4000R (polypropylene glycol glyceryl ether manufactured by NOF Corporation), and while stirring with a disperser, 30.0 parts of the preliminary dispersion of fine particles OC-1 was added, followed by stirring and mixing at 2000 rpm for 15 minutes to obtain surface conditioner sample E1.

[0164] <Surface Conditioner Sample E2> Surface conditioner sample E2 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-3.

[0165] <Surface Conditioner Sample E3> Surface conditioner sample E3 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-4.

[0166] <Surface Conditioner Sample E4> Surface conditioner sample E4 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-5.

[0167] <Surface Conditioner Sample E5> Surface conditioner sample E5 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-6.

[0168] <Surface Conditioner Sample E6> Surface conditioner sample E6 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to a pre-dispersion of fine particles OC-10.

[0169] <Surface Conditioner Sample E7> Surface conditioner sample E7 was obtained in the same manner as for surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-9.

[0170] <Surface conditioner sample E8> Surface conditioner sample E8 was obtained in the same manner as surface conditioner sample E1, except that the amount of Uniol TG-4000R added was changed to 52.0 parts and the amount of the preliminary dispersion of fine particles OC-1 added was changed to 13.0 parts.

[0171] <Surface conditioner sample E9> Surface conditioner sample E9 was obtained in the same manner as surface conditioner sample E1, except that the amount of Uniol TG-4000R added was changed to 13.0 parts and the amount of the preliminary dispersion of fine particles OC-1 added was changed to 52.0 parts.

[0172] <Surface Conditioner Sample E10> Surface conditioner sample E10 was obtained in the same manner as for surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-7.

[0173] <Surface Conditioner Sample E11> Surface conditioner sample E11 was obtained in the same manner as for surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-8.

[0174] <Surface conditioner samples E12 to 15, E17, E19 to E21, E23, E26 to E27, E30 to E31, E33, E43> Surface conditioner samples E12 to 15, E17, E19 to E21, E23, E26 to E27, E30 to E31, E33, and E43 were obtained in the same manner as for surface conditioner sample E1, except that Uniol TG-4000R was changed to "A: Polymer" shown in Tables 5, 6, and 7.

[0175] <Surface conditioner sample E16> Surface conditioner sample E16 was obtained in the same manner as for surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to 27.5 parts of Polymer 3 and 7.5 parts of EMALEX (registered trademark) RWIS-320 (polyethylene glycol hydrogenated castor oil triisostearate, manufactured by Nippon Emulsion Co., Ltd.).

[0176] <Surface conditioner sample E18> Surface conditioner sample E18 was obtained in the same manner as surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to 35.0 parts of a Merveilleux 30 solution of Polymer 4 (polymer concentration: 50% by mass).

[0177] <Surface conditioner sample E22> Surface conditioner sample E22 was obtained in the same manner as surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to 7.5 parts of EMALEX RWIS-320 and 27.5 parts of PIBVE (an isoparaffin solution with a PIBVE concentration of 60% by mass) manufactured by Siwei Development Group, Ltd.

[0178] <Surface conditioner sample E24> Surface conditioner sample E24 was obtained in the same manner as surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to a polymer diluted solution prepared by diluting 17.5 parts of Polymer 6 with 17.5 parts of 2-ethylhexanol.

[0179] <Surface conditioner sample E25> Surface conditioner sample E25 was obtained in the same manner as surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to a polymer diluted solution prepared by diluting 28.0 parts of Polymer 7 with 7.0 parts of 2-ethylhexanol.

[0180] <Surface conditioner sample E28> Surface conditioner sample E28 was obtained in the same manner as surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-2 and Uniol TG-4000R was changed to Newpol LB-625.

[0181] <Surface conditioner sample E29> Surface conditioner sample E29 was obtained in the same manner as surface conditioner sample E1, except that 35.0 parts of Uniol TG-4000R was changed to 35.0 parts of a solution of polymer 9 in Merveille 30 (solvent) (polymer concentration: 50% by mass).

[0182] <Surface conditioner sample E32> Surface conditioner sample E32 was obtained in the same manner as surface conditioner sample E1, except that Uniol TG-4000R was changed to PTMG650 (polybutylene glycol manufactured by Mitsubishi Chemical Corporation) and the pre-dispersion of fine particles OC-1 was changed to a pre-dispersion of fine particles OC-11.

[0183] <Surface conditioner sample E34> Surface conditioner sample E34 was obtained in the same manner as surface conditioner sample E1, except that Uniol TG-4000R was changed to SY Glystar PO-3S (polyglyceryl-4 pentaoleate manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) and the pre-dispersion of fine particles OC-1 was changed to a pre-dispersion of fine particles OC-6.

[0184] <Surface conditioner samples E35 to E37> Surface conditioner samples E35 to E37 were obtained in the same manner as for surface conditioner sample E1, except that Uniol TG-4000R was changed to "A: polymer" shown in Table 7, and the pre-dispersion of fine particles OC-1 was changed to the pre-dispersion of fine particles OC-12.

[0185] <Surface conditioner samples E38 to E42> Surface conditioner samples E38 to E42 were obtained in the same manner as for surface conditioner sample E1, except that the pre-dispersion of fine particles OC-1 was changed to "B: organic solid fine particles" and "C: organic medium" as shown in Table 7.

[0186] <Surface conditioner sample C1> Surface conditioner sample C1 was obtained in the same manner as surface conditioner sample E1, except that 24.0 parts of Merveilles 30 and 6.0 parts of ethanol were used instead of 30.0 parts of the preliminary dispersion of fine particles OC-1.

[0187] <Surface conditioner sample C2> Surface conditioner sample C2 was obtained in the same manner as surface conditioner sample E30, except that 24.0 parts of Merveilles 30 and 6.0 parts of ethanol were used instead of 30.0 parts of the preliminary dispersion of fine particles OC-1.

[0188] <Surface conditioner sample C3> Surface conditioner sample C3 was obtained in the same manner as surface conditioner sample E27, except that 24.0 parts of Merveilles 30 and 6.0 parts of ethanol were used instead of 30.0 parts of the preliminary dispersion of fine particles OC-1.

[0189] <Surface Conditioner Sample C4> A pre-dispersion of fine particles OC-1 was used as surface conditioner sample C4.

[0190] <Surface conditioner sample C5> Surface conditioner sample C5 was obtained in the same manner as for surface conditioner sample E1, except that Uniol TG-4000R was changed to MFDG (dipropylene glycol monomethyl ether manufactured by Nippon Nyukazai Co., Ltd.), which is a non-A component.

[0191] <Surface conditioner sample C6> Surface conditioner sample C6 was obtained in the same manner as surface conditioner sample E1, except that Uniol TG-4000R was changed to an ethanol solution of polymer 10 (polymer concentration: 50 mass%), which is a non-A component.

[0192] <Surface conditioner sample C7> 13.0 parts of FS1265-10000cst (fluorine-modified silicone manufactured by Dow Toray Industries, Inc.) was diluted with 39.0 parts of methyl isobutyl ketone to obtain a polymer dilution. Next, the polymer dilution was charged into a 100 mL plastic cup, and 13.0 parts of the pre-dispersion of fine particles OC-1 was added while stirring with a disper, and then the mixture was stirred and mixed at 2000 rpm for 15 minutes to obtain surface conditioner sample C7.

[0193] <Surface conditioner sample C8> Surface conditioner sample C8 was obtained in the same manner as surface conditioner sample E1, except that Uniol TG-4000R was changed to SY Glystar MO-3S (polyglyceryl-4 monooleate, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.), which is a non-A component, and the pre-dispersion of fine particles OC-1 was changed to a pre-dispersion of fine particles OC-12.

[0194] <Surface conditioner sample C9> Surface conditioner sample C9 was obtained in the same manner as surface conditioner sample E1, except that Uniol TG-4000R was changed to SY Glyster PO-3S (polyglyceryl-4 pentaoleate manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) and 46.2 parts of Merveilleux 30 was used instead of the pre-dispersion of fine particles OC-1.

[0195] <Surface Conditioner Sample C10> Agitan 295 (manufactured by MUNZING CHEMIE GmbH), which is a mixture of hydrocarbon, hydrophobic silica, and an alkoxy compound, was used as surface conditioner sample C10.

[0196] <Surface Conditioner Sample C11> As surface conditioner sample C11, BYK-024 (manufactured by BYK Corporation), which is a mixture of silicone, hydrophobic fine particles, and polyglycol, was used.

[0197] The compositions of the surface conditioner samples prepared as described above are shown in Tables 4 to 8 below.

[0198]

[0199]

[0200]

[0201]

[0202]

[0203] [Preparation of Water-Based Paints] Two types of water-based paints (Blank) were prepared according to the formulations shown in Tables 9 and 11 below. The formulation of the water-based paint shown in Table 9 is the formulation of a first water-based colored paint (BC-1) containing a color pigment and a surface conditioner, and the formulation of the water-based paint shown in Table 11 is the formulation of a second water-based colored paint (BC-2) containing a color pigment, a luster pigment, and a surface conditioner. The first water-based colored paint and the second water-based colored paint were prepared by preparing the pigment pastes (P-1) and (P-2) to be used for the respective water-based paints in advance and mixing these pigment pastes with other paint components. The formulations of the pigment pastes (P-1) and (P-2) are shown in Tables 10 and 12, respectively. The surface conditioner Sample E27 was added when preparing the first water-based colored paint (BC-1) and the second water-based colored paint (BC-2). This surface conditioner was added to eliminate bubbles that were generated when preparing the first water-based colored paint (BC-1) and the second water-based colored paint (BC-2).

[0204]

[0205]

[0206]

[0207]

[0208] (Preparation of First Water-Based Colored Paint) A water-soluble acrylic resin, white pigment, black pigment, solvent, water, dispersant, and surface conditioner Sample E27 were added to a container in the amounts shown in Table 10. Zirconia beads were added to the mixture of these raw materials, and the mixture was dispersed using a paint shaker for 60 minutes to prepare a first water-based colored paint pigment paste (P-1). After dispersion was completed, the zirconia beads were removed. Next, the water-soluble acrylic resin, iminomethylated melamine resin, water, pH adjuster, solvent, and surface conditioner Sample E27 were sequentially added to this pigment paste (P-1) in the amounts shown in Table 9, and mixed using a Lab-DiSpar to obtain a first water-based colored paint (BC-1).

[0209] (Preparation of Second Water-Based Colored Paint) Black pigment, water, dispersant, and surface conditioner Sample E27 were added to a container in the amounts shown in Table 12. Zirconia beads were added to the mixture of these raw materials, and the mixture was dispersed using a paint shaker for 60 minutes to prepare a pigment paste (P-2) for the second water-based colored paint. After dispersion was completed, the zirconia beads were removed. Next, the acrylic polyol dispersion, acrylic-modified urethane dispersion, iminomethylated melamine resin, viscosity modifier, pH adjuster, water, solvent, and lustrous pigment were sequentially added to this pigment paste (P-2) in the amounts shown in Table 11, and mixed using a Lab-Di-Spar to obtain a second water-based colored paint (BC-2).

[0210] (Preparation of Clear Coating) First, a resin to be blended in the clear coating was synthesized as follows.

[0211] Synthesis of Hydroxyl-Containing Acrylic Resin (C-1) 330.0 parts of ethyl 3-ethoxypropionate was placed in a 2000 ml reaction vessel equipped with a stirrer, a reflux condenser, a dropping device, a thermometer, and a nitrogen gas inlet tube, and the internal temperature was then raised to 155° C. while stirring under a nitrogen gas stream. The dropping solution in the dropping apparatus was 290.4 parts of hydroxypropyl acrylate (trade name HPA: manufactured by Osaka Organic Chemical Industry Co., Ltd.), 88.0 parts of polypropylene glycol monomethacrylate (trade name Blemmer PP-1000: manufactured by NOF Corporation), 88.0 parts of isobornyl acrylate (trade name IBXA: manufactured by Osaka Organic Chemical Industry Co., Ltd.), 44.0 parts of 2-hydroxyethyl methacrylate (trade name Acryester HO: manufactured by Mitsubishi Chemical Corporation), 44.0 parts of 2-hydroxyethyl acrylate, 176.0 parts of styrene, 132.0 parts of methyl methacrylate (trade name Acryester M: manufactured by Mitsubishi Chemical Corporation), 17.6 parts of methacrylic acid, and 36.96 parts of di-t-amyl peroxide (trade name Luperox DTA: manufactured by Arkema Yoshitomi Co., Ltd.). Next, the internal temperature of the reaction vessel was maintained at 155 ° C., and the dropping solution was added dropwise uniformly over 240 minutes. After the dropwise addition was completed, the reaction temperature was maintained for 120 minutes to allow the reaction to proceed. After the reaction was completed, the internal temperature of the reaction vessel was lowered to 100°C, and 259.6 parts of butyl acetate was added. The resin solids content was adjusted to 60% with ethyl 3-ethoxypropionate / butyl acetate (56 / 44) to obtain a hydroxyl group-containing acrylic resin (C-1). The weight average molecular weight of the synthesized hydroxyl group-containing acrylic resin was 5,500 (hydroxyl value: 200 mg KOH / g, SP value: 11.0).

[0212] <Preparation of clear coating material> Next, an isocyanate curing agent, a diluent, and a surface conditioner (leveling agent) were added in that order to the hydroxyl group-containing acrylic resin (C-1) in the amounts shown in Table 13, and mixed using a Lab-Di-Spar to prepare a clear coating material.

[0213]

[0214] [Evaluation Method] Evaluation tests were carried out as follows using the first water-based colored paint, the second water-based colored paint and the clear paint obtained as described above.

[0215] (Evaluation of popping prevention property) A multi-layer coating film to be used for evaluating popping prevention property (hereinafter referred to as "popping prevention evaluation coating film") was prepared, and the popping prevention property was evaluated by observing the state of popping occurrence in this popping prevention evaluation coating film. Details are described below.

[0216] <Preparation of coating film for evaluation of watermark prevention> The first waterborne colored coating material (BC-1) was applied to a glass plate using a wireless bar coater OSP-80, and the plate was left to stand at room temperature for 5 minutes, followed by preheating for 5 minutes at 80° C. Next, onto the uncured coating film obtained from this first waterborne colored coating material, a second waterborne colored coating material was applied using a 6 mil applicator, which had been prepared by adding any one of surface conditioner samples E1 to E43 and C1 to C11 to the coating material in a predetermined amount and dispersing the surface conditioner using a disperser at 2000 rpm for 5 minutes. The second waterborne colored coating material was then applied using a 6 mil applicator, and the plate was left to stand at room temperature for 5 minutes, followed by preheating for 5 minutes at 80° C. Furthermore, a clear coating was applied onto the uncured coating film obtained from this second aqueous colored coating using a wireless bar coater OSP-80, and after leaving it to stand at room temperature for 5 minutes, it was heated at 140°C for 30 minutes, and the multi-layer coating film was simultaneously cured and dried, thereby obtaining coatings for evaluation of water spurt prevention for Examples 1 to 43 and Comparative Examples 1 to 11. The surface conditioner samples added to the second aqueous colored coating when preparing the coatings for evaluation of water spurt prevention for each Example and Comparative Example are shown in Tables 14 and 15 below. As shown in Table 15, a blank evaluation coating was also prepared in which no surface conditioner was added to the second aqueous colored coating when preparing the coatings for evaluation of water spurt prevention.

[0217] <Method of evaluating coating films for evaluating water spurt prevention> The water spurt occurrence status of the coating films for evaluating water spurt prevention obtained as described above for Examples 1 to 43, Comparative Examples 1 to 11, and Blank was visually observed and evaluated on a four-point scale according to the following criteria: A (Excellent): No water spurts were observed in the coating film B (Good): A few water spurts were observed in the coating film C (Fair): Water spurts were observed in part of the coating film D (Poor): Water spurts were observed over the entire surface of the coating film

[0218] (Evaluation of Recoatability) A multilayer coating film to be used for evaluating recoatability (hereinafter referred to as "recoatability evaluation coating film") was prepared, and the appearance of this recoatability evaluation coating film was observed to evaluate the recoatability. Details are described below.

[0219] <Preparation of coating film for evaluation of topcoatability> A first water-based colored coating (BC-1) was applied to an SPCC-SD electrodeposition coated plate (manufactured by Paltec Co., Ltd.) using a wireless bar coater OSP-80 and an automatic film applicator AFA-standard (manufactured by TQC Sheen Co., Ltd.), and the coating was left to stand at room temperature for 5 minutes, and then preheated for 5 minutes at 80 ° C. Next, a surface conditioner selected from surface conditioner samples E1 to E43 and C1 to C11 was added to the uncured coating film obtained with this first water-based colored coating, and the coating was dispersed at 2000 rpm for 5 minutes using a disper, and then the second water-based colored coating, which had been degassed using a defoamer, was applied using a wireless bar coater OSP-80, and the coating was left to stand at room temperature for 5 minutes, and then preheated for 5 minutes at 80 ° C. Furthermore, a clear coating was applied onto the uncured coating film obtained from this second aqueous colored coating using a wireless bar coater OSP-80, and after leaving it to stand at room temperature for 5 minutes, it was heated at 140 ° C. for 30 minutes, and the multi-layer coating film was simultaneously cured and dried to obtain the overcoatability evaluation coating films of Examples 1 to 43 and Comparative Examples 1 to 11. The surface conditioner samples added to the second aqueous colored coating when preparing the overcoatability evaluation coating films of each Example and Comparative Example are shown in Tables 14 and 15 below. As shown in Table 15, a blank evaluation coating film was also prepared in which no surface conditioner was added to the second aqueous colored coating when preparing the overcoatability evaluation coating film.

[0220] <Method for evaluating coating films for topcoatability evaluation> The appearance of the coating films for topcoatability evaluation obtained as described above in Examples 1 to 43, Comparative Examples 1 to 11, and Blank was visually observed and evaluated on a four-point scale according to the following criteria: A (Excellent): The coating film appearance is good B (Good): The coating film has slightly poor smoothness C (Fair): Dents or foreign matter are observed in parts of the coating film D (Poor): Repelling or foreign matter is observed throughout the coating film

[0221] [Evaluation Results] The results of the performance evaluation as described above are shown in Tables 14 and 15.

[0222]

[0223]

[0224] The multilayer coating films of Examples 1 to 43 (coating films for evaluation of pumping prevention and topcoatability) were evaluated to have the performance required for the present invention in both pumping prevention and topcoatability.

[0225] Examples 1, 12 to 17, 19 to 21, 23, 25, 26, 27, 30, 31, 33, 43, etc. show that by using polyalkylene glycols and their derivatives, polyalkyl acrylates, polyvinyl alkyl ethers, polybutenes, polyglycerin fatty acid esters, etc. as polymer (A), the anti-pile properties and recoatability are particularly excellent.

[0226] Furthermore, it is clear from Examples 1 to 7, 10 and 11 that when the aspect ratio of the organic solid fine particles (B) is in the range of 1.5 to 30, the anti-pile property and the recoatability are particularly excellent.

[0227] On the other hand, Comparative Examples 1 to 3 and 9, which did not contain the organic solid fine particles (B) as a surface conditioner component, and Comparative Example 4, which did not contain the polymer (A), all had poor anti-flake properties.

[0228] Furthermore, Comparative Examples 5 to 8, which contained a polymer (non-A component) that does not correspond to the polymer (A) of the present invention, were poor in either pumping prevention or recoatability. In particular, Comparative Example 7, which contained a silicone compound as the polymer, was excellent in pumping prevention but poor in recoatability.

[0229] Furthermore, Comparative Example 10, which contained hydrophobic silica particles as a surface conditioner component, and Comparative Example 11, which contained silicone and hydrophobic particles, were inferior in overcoatability. Furthermore, Comparative Example 11, which contained silicone and hydrophobic particles, was also inferior in anti-pile properties.

Claims

1. A surface conditioner for water-based paints, comprising: a polymer (A) having an SP value of 6 to 12, a weight average molecular weight of 200 to 1,000,000, and having at least 3 or more repeating units; and organic solid fine particles (B) that are in a solid state in the surface conditioner at 25°C. The surface conditioner is characterized by containing these components.

2. The surface conditioner according to claim 1, wherein the polymer (A) is one or more polymers selected from the group consisting of polyvinyl alkyl ethers, polybutadienes, polybutenes, polyalpha olefins, polyalkyl (meth) acrylates, copolymers of dibasic acid esters, polyvinyl fatty acid esters, polyalkylene glycols and their derivatives, polyamides, polyglycerin fatty acid esters, and polyesters.

3. The surface conditioner according to claim 1, wherein the organic solid fine particles (B) are one or more solid fine particles selected from the group consisting of amides, ureas, polyethylenes, oxidized polyethylenes, acid-modified polyethylenes, ethylene vinyl acetate copolymers, ethylene (meth) acrylic acid copolymers, polypropylenes, acid-modified polypropylenes, and hydrogenated castor oil.

4. The surface conditioner according to claim 3, wherein the amide is a fatty acid diamide obtained by reacting fatty acids selected from the group consisting of alkyl fatty acids and hydroxy fatty acids and containing at least one or more hydroxy fatty acids, with diamines selected from the group consisting of alkylene diamines having 2 to 6 carbon atoms and m-xylylenediamine and containing one or more diamines.

5. The surface conditioner according to claim 1, wherein the aspect ratio of the crystals of the organic solid fine particles (B) is 1.1 to 100.

6. The surface conditioner according to claim 1, wherein the mode diameter of the organic solid fine particles (B) is 0.1 to 150 μm.

7. Further comprising an organic medium (C) that is liquid at 25°C other than water, and the organic medium (C) is characterized by having 0 to 2 repeating units. The surface conditioner according to claim 1.

8. The surface conditioner according to claim 7, wherein the organic medium (C) is one or more selected from the group consisting of hydrocarbon oils, alcohols, glycol ethers, glycol esters, and polyhydric alcohol fatty acid esters.

9. An aqueous coating composition comprising the surface conditioner according to any one of claims 1 to 8 and an aqueous resin.

10. An article coated with a coating agent containing the surface conditioner according to any one of claims 1 to 8.

11. A method for forming a multi-layer coating film having a film-forming step of sequentially coating at least two or more aqueous coatings on a surface of an object to be coated in a wet-on-wet manner and then simultaneously heat-curing the aqueous coatings applied to the object to be coated to form at least two or more coating films, wherein at least one of the two or more aqueous coatings contains the surface conditioner according to any one of claims 1 to 8.

12. As the two or more aqueous coatings, a first aqueous coating containing a coloring pigment and a second aqueous coating containing a brightening pigment are used, at least one of the first aqueous coating and the second aqueous coating contains the surface conditioner, and in the film-forming step, after sequentially coating the first aqueous coating, the second aqueous coating, and a clear coating in a wet-on-wet manner, the first aqueous coating, the second aqueous coating, and the clear coating are simultaneously heat-cured to form a first aqueous resin coating film, a second aqueous resin coating film, and a clear coating film laminated in this order from the object-to-be-coated side on the surface of the object-to-be-coated. The method for forming a multi-layer coating film according to claim 11.

Images