Viscosity modifier for water-based resin and water-based coating composition

Abstract

The present invention provides a viscosity modifier for water-based resin and a water-based coating composition containing the viscosity modifier, which can reduce the amount of neutralization alkali used in the viscosity modifier, and has excellent viscosity imparting effect, pseudoplasticity imparting effect and thermal stability, and can exert these effects under a wide pH range from acidic to alkaline. A viscosity modifier for water-based resin, comprising: a viscosity imparting component (X) containing 1% to 30% by mass of a diamide compound (A) and / or hydrogenated castor oil (A'), wherein the diamide compound (A) is obtained by reacting a diamine component (A1) with a monocarboxylic acid component (A2), wherein the diamine component (A1) is selected from the group consisting of diamines having 2 to 12 carbon atoms, and the monocarboxylic acid component (A2) is selected from the group consisting of monocarboxylic acids having at least a hydroxyl group; and 5 to 99% by mass of a first solvent (C), having at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, an amide group and a ketone group.

Description

Technical Field

[0001] The present invention relates to a viscosity modifier for water-based resin and a water-based coating composition. Background Art

[0002] Since water-based paint is a paint corresponding to environmental protection, its application field is increasing, and the adoption of water-based paint in the field of anti-corrosion paint is also increasing. In these water-based paints, many types of thixotropic agents are used, for example, for the purpose of preventing the pigment from settling and hardening and caking in the paint during storage, preventing the paint from sagging during painting, and smoothing the coating surface. As such a thixotropic agent, for example, there are anti-settling agents as described in Patent Documents 1 and 2. Patent Documents 1 and 2 disclose an anti-settling agent for water-based paint, which is obtained by neutralizing a polyamide obtained by reacting a diamine and a dicarboxylic acid in excess relative to the diamine with a neutralizing base (amine, etc.) and then dispersing it in a medium with water as the main body.

[0003] However, in the case of using a neutralization base as described in the above-mentioned patent documents 1 and 2, in the water-based epoxy primer (main agent) used in the field of anti-corrosion coatings, when an aqueous viscosity modifier of an amide type neutralized with a base such as an amine is added, there is a problem that the epoxy resin of the main agent reacts with the amine used for neutralization and gels. In addition, in the water-based epoxy primer, the pH of the main agent is in the range of acidic to neutral, but becomes alkaline when mixed with an amine that uses the main agent as a curing agent, so a viscosity modifier for a water-based resin is desired, which shows the effects of anti-settling, anti-sagging, etc. at a wide pH range from acidic to alkaline. Further, in the case of using water-based coatings other than water-based epoxy primers, there is also a problem that the odor (amine odor, etc.) is unpleasant when using a neutralization base such as an amine, and improvement is also desired in this regard.

[0004] As an example of a thixotropic agent that does not use a neutralization base as described above, Patent Document 3 discloses a paste thixotropic agent that contains no particulate product, which is obtained by dispersing fine particles of a diamide compound that is a condensation reaction product of hydrogenated castor oil fatty acid and a primary diamine in a mixed solvent consisting of an alcohol solvent and at least one solvent selected from cyclic saturated hydrocarbons and esters and then heating the mixture. The paste thixotropic agent described in Patent Document 3 is believed to provide an amide paste thixotropic agent that does not contain particulate matter in the paste that causes problems such as poor dispersion.

[0005] As another example of a thixotropic agent that does not use a neutralizing base, a polyurethane thickener (polyurethane thickener) composed of polyoxyalkylene glycol and polyisocyanate is disclosed in Patent Document 4. The polyurethane thickener described in Patent Document 4 is generally used for water-based coatings.

[0006] Prior art literature

[0007] Patent Literature

[0008] Patent Document 1: Japanese Patent Application Laid-Open No. 10-310726

[0009] Patent Document 2: Japanese Patent Application Publication No. 2012-111832

[0010] Patent Document 3: Japanese Patent Application Publication No. 2002-146336

[0011] Patent Document 4: Japanese Patent Application Laid-Open No. 11-199854 Summary of the invention

[0012] Technical Problems to be Solved by the Invention

[0013] However, in the pasty thixotropic agent described in Patent Document 3, non-aqueous solvents such as cyclic saturated hydrocarbons and esters are used, and the thixotropic agent using such non-aqueous solvents is not easy to disperse in the aqueous resin solution used for aqueous coatings. Therefore, it is difficult to use the thixotropic agent of Patent Document 3 as a viscosity modifier for aqueous coatings (aqueous resin solutions).

[0014] Furthermore, the polyurethane thickener described in Patent Document 4 has a problem of being inferior in viscosity-imparting effect, pseudoplasticity-imparting effect, thermal stability and the like, compared to amide-based viscosity modifiers.

[0015] Therefore, the present invention has been made in view of the above circumstances, and an object of the present invention is to provide a viscosity modifier for an aqueous resin and an aqueous coating composition containing the viscosity modifier, which can reduce the amount of a neutralizing alkali used in the viscosity modifier, and are excellent in viscosity-imparting effect, pseudoplasticity-imparting effect and thermal stability, and can exhibit these effects in a wide pH range from acidic to alkaline.

[0016] Technical solutions for solving technical problems

[0017] The present inventors have conducted intensive studies in order to solve the above-mentioned technical problems and have found that by making a viscosity modifier for an aqueous resin contain a diamide compound having a specific structure and a solvent having a specific structure, the amount of a neutralizing base used in the viscosity modifier can be reduced, and that the viscosity-imparting effect, pseudoplasticity-imparting effect and thermal stability are excellent, and that these effects can be exerted in a wide pH range from acidic to alkaline. The present invention has been completed based on this finding.

[0018] That is, the present invention is a viscosity modifier for an aqueous resin, characterized in that it contains: 1% to 30% by mass of a viscosity-imparting component (X), wherein the viscosity-imparting component (X) comprises a diamide compound (A) and / or hydrogenated castor oil (A'), wherein the diamide compound (A) is obtained by reacting a diamine component (A1) with a monocarboxylic acid component (A2), wherein the diamine component (A1) is selected from the group consisting of diamines having 2 to 12 carbon atoms, and the monocarboxylic acid component (A2) is selected from the group consisting of monocarboxylic acids having at least a hydroxyl group; and 5 to 99% by mass of a first solvent (C), wherein the first solvent (C) has at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, an amide group, and a ketone group,

[0019] When the total amount of the viscosity-imparting component (X) is 100 parts by mass, the total amount of the diamide compound (A) and the hydrogenated castor oil (A') is 60 parts by mass or more.

[0020] In one embodiment of the present invention, the viscosity-imparting component (X) further contains a polyamide compound (B) obtained by reacting a diamine component (B1) with a dicarboxylic acid component (B2) in an excess amount relative to the diamine component (B1), and the acid value of the polyamide compound (B) is 30 to 140. When the total amount of the viscosity-imparting component (X) is 100 parts by mass, the content of the polyamide compound (B) may be 40 parts by mass or less.

[0021] In another embodiment of the present invention, the first solvent (C) is preferably a solvent having an HLB value calculated by the Davis method of 3 to 10. Alternatively, further, in another embodiment of the present invention, the first solvent (C) is preferably at least one solvent selected from the group consisting of alcohol solvents, glycol ether solvents, di(glycol) ether solvents, tri(glycol) ether solvents, ester solvents, and amide solvents.

[0022] In another embodiment of the present invention, a nonionic surfactant (E) having an HLB value of 3 to 18.5 calculated by the Griffin method may be further contained, and the content of the surfactant (E) is 300 parts by mass or less relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A').

[0023] In another embodiment of the present invention, a second solvent (F) having a relatively higher polarity than the first solvent (C) may be further contained, and the content of the second solvent (F) may be 20% by mass or less.

[0024] In another embodiment of the present invention, water (D) may be further contained, and the content of the water (D) may be 80% by mass or less.

[0025] The present invention also provides an aqueous coating composition comprising an aqueous resin, a pigment, and the above-mentioned viscosity modifier for the aqueous resin.

[0026] In another embodiment of the present invention, the aqueous resin viscosity modifier may be contained in an amount of 0.1% by mass to 1.0% by mass of the viscosity-imparting component (X) relative to the total solid content of the aqueous coating composition.

[0027] Effects of the Invention

[0028] According to the present invention, by making the aqueous resin viscosity modifier contain a diamide compound having a specific structure and a solvent having a specific structure, the amount of the neutralization base used in the viscosity modifier can be reduced, and the viscosity-imparting effect and pseudoplasticity-imparting effect on the aqueous coating material containing the viscosity modifier and the thermal stability of the aqueous coating material are excellent, and these effects can be exerted in a wide pH range from acidic to alkaline. DETAILED DESCRIPTION

[0029] Hereinafter, preferred embodiments of the present invention will be described in detail.

[0030] [Viscosity adjuster]

[0031] The viscosity modifier of the present invention is an additive used together with an aqueous resin in an aqueous coating composition, and contains a viscosity-imparting component (X) containing a diamide compound (A) and / or hydrogenated castor oil (A'), and a first solvent (C) as essential components. Thus, according to the present invention, the amount of the neutralizing alkali used in the viscosity modifier can be reduced, and the viscosity-imparting effect and pseudoplasticity-imparting effect on the aqueous coating containing the viscosity modifier and the thermal stability of the aqueous coating are excellent, and these effects can be exerted in a wide pH range from acidic to alkaline.

[0032] Here, the viscosity imparting effect in the present invention refers to the effect of increasing (thickening) the viscosity of the water-based paint to which the viscosity modifier is added. In addition, the pseudoplasticity imparting effect in the present invention refers to the effect of imparting the property of reducing the viscosity of the water-based paint to which the viscosity modifier is added under shear stress. Further, the thermal stability in the present invention refers to the property of small changes in the anti-settling property accompanying temperature changes. Hereinafter, these essential components and the optional components contained in the viscosity modifier of the present invention are described in detail.

[0033] (Viscosity-imparting component (X))

[0034] The viscosity imparting component (X) of the present invention is an effective component added to impart viscosity and pseudoplasticity to the aqueous coating composition to which the viscosity modifier is added and to improve the thermal stability of the aqueous coating composition. As the viscosity imparting component (X), at least one of the diamide compound (A) and the hydrogenated castor oil (A') is included as an essential component. In addition, as an arbitrary component of the viscosity imparting component (X), a polyamide compound (B) is included. That is, as the viscosity imparting component (X) included in the viscosity modifier of the present invention, it is possible that (1) only the diamide compound (A), (2) only the hydrogenated castor oil (A'), (3) a combination of the diamide compound (A) and the hydrogenated castor oil (A'), (4) a combination of the diamide compound (A) and the polyamide compound (B), (5) a combination of the hydrogenated castor oil (A') and the polyamide compound (B), and a combination of the diamide compound (A), the hydrogenated castor oil (A') and the polyamide compound (B). Furthermore, as shown in Examples described later, from the viewpoint of improving thermal stability, it is preferred that at least a diamide compound (A) is contained as the viscosity-imparting component (X).

[0035] <Diamide compound (A)>

[0036] The diamide compound (A) of the present invention is a fatty acid diamide obtained by reacting a diamine component (A1) and a monocarboxylic acid component (A2).

[0037] As raw materials for obtaining the diamide compound (A) of the present invention, there are diamine components (A1) selected from the group consisting of diamines having 2 to 12 carbon atoms, and monocarboxylic acid components (A2) selected from the group consisting of straight-chain saturated fatty acids having at least a hydroxyl group. As diamine components (A1) and monocarboxylic acid components (A2), the following compounds can be cited. In addition, the reaction conditions (reaction temperature, ratio of each component, etc.) can be appropriately set by a known method. In this case, a dehydration aid such as xylene can also be used as needed.

[0038] <<Diamine component (A1)>>

[0039] As the diamine component (A1) of the present invention, for example, aliphatic diamines such as ethylenediamine (EDA), propylenediamine, tetramethylenediamine (TMDA), hexamethylenediamine (HMDA), octamethylenediamine (OMDA), and 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 and isophoronediamine can be used.

[0040] As the main component of the diamide compound (A), a hydroxyl-containing diamide obtained by reacting these diamines with a monocarboxylic acid having at least a hydroxyl group described later is used, thereby obtaining sufficient viscosity imparting effect, pseudoplasticity imparting effect and thermal stability. However, in order to further improve the viscosity imparting effect, pseudoplasticity imparting effect and thermal stability effect, among the above-mentioned diamines, a straight-chain or branched diamine (for example, EDA, TMDA, HMDA, OMDA, DMDA, etc.) is more preferably used as the diamine component (A1). In addition, from the viewpoint of improving anti-settling properties, as the diamine component (A1), a diamine having a carbon number of 10 or less is preferably used.

[0041] <<Monocarboxylic acid component (A2)>>

[0042] The monocarboxylic acid component (A2) of the present invention is not particularly limited as long as it contains a monocarboxylic acid having at least a hydroxyl group. As the monocarboxylic acid having a hydroxyl group, for example, a compound in which a part of the hydrogen atoms of a saturated aliphatic monocarboxylic acid such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, heptanoic acid, caprylic acid, nonanoic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid (docosanoic acid) are substituted with a hydroxyl group, and a compound in which a part of the hydrogen atoms of an unsaturated aliphatic monocarboxylic acid such as oleic acid, linoleic acid, ricinoleic acid, linolenic acid, eicosenoic acid, erucic acid, a mixed fatty acid obtained from natural oils and fats (tall oil fatty acid, rice bran fatty acid, soybean oil fatty acid, tallow fatty acid, etc.) are substituted with a hydroxyl group.

[0043] In order to improve the viscosity imparting effect, pseudoplasticity imparting effect and thermal stability effect of the viscosity modifier of the present invention, it is preferred that the monocarboxylic acid component (A2) contains at least hydrogenated castor oil fatty acid such as 12-hydroxystearic acid (hereinafter referred to as "12-HSA") obtained by saponifying hydrogenated castor oil. In addition, when an alkanoic acid is contained as a raw material of the diamide compound (A), the carbon number of the alkanoic acid is preferably 16 or less from the viewpoint of improving thermal stability.

[0044] In order to prevent unreacted groups from remaining, the reaction molar ratio (A1 / A2) of the diamine component (A1) to the monocarboxylic acid component (A2) when synthesizing the diamide compound (A) is preferably 1: 2. In addition, the reaction molar ratio (A1 / A2) refers to the ratio (molar ratio) of the amount of the diamine component (A1) to the amount of the monocarboxylic acid component (A2).

[0045] <Hydrogenated castor oil (A')>

[0046] Hydrogenated castor oil (A') is a triglyceride of saturated fatty acids obtained by hydrogenating castor oil, and is a compound having no ethylene oxide (EO) chain. Commercially available products can be used as hydrogenated castor oil (A'), and examples of commercially available products include C-wax (manufactured by Kokura Synthetic Industry Co., Ltd.), Kao wax 85P (manufactured by Kao Corporation), castor solidified oil (manufactured by Sankei Sangyo Co., Ltd.), and the like.

[0047] <Polyamide compound (B)>

[0048] The viscosity-imparting component (X) of the present invention contains at least one of the above-mentioned diamide compound (A) and hydrogenated castor oil (A') as an essential component, but in addition thereto, it may contain a polyamide compound (B) as an optional component. The polyamide compound (B) is a polyamide obtained by reacting a diamine component (B1) with a dicarboxylic acid component (B2) in an excess amount relative to the diamine component (B1).

[0049] As a polyamide compound (B), it can be obtained by reacting the above-mentioned diamine component (B1) with a dicarboxylic acid component (B2). As long as it is a polymer compound having an amide bond (-CONH-), any polyamide with any chemical structure can be used. In addition, the reaction conditions (reaction temperature, ratio of each component, etc.) can be appropriately set by a known method. In this case, a dehydration aid such as xylene can also be used as needed. At this time, it is preferred that the reaction molar ratio (B1 / B2) of the diamine component (B1) and the dicarboxylic acid component (B2) is less than 1. That is, it is preferred to react an excess (molar ratio) of the carboxylic acid component (B2) relative to the amine component (B1). In this case, at least one end of the polyamide compound (B) is a carboxyl group. However, in order to obtain the desired effect in the present invention, at least one end of the polyamide compound (B) may not necessarily be a carboxyl group, and all ends may also be amino groups. In addition, the reaction molar ratio (B1 / B2) refers to the ratio (molar ratio) of the amount of the amine component (B1) to the amount of the carboxylic acid component (B2).

[0050] <<Diamine component (B1)>>

[0051] As the diamine component (B1), at least one amine selected from the group consisting of diamines having 2 to 12 carbon atoms can be used. Examples of the diamine include aliphatic diamines such as ethylenediamine (EDA), propylenediamine, tetramethylenediamine (TMDA), hexamethylenediamine (HMDA), octamethylenediamine (OMDA), and dodecamethylenediamine (DMDA); aromatic diamines such as xylylenediamine, diaminodiphenyl ether, and diaminodiphenyl sulfone; and alicyclic diamines such as piperazine and isophoronediamine. Each compound used as the diamine component (B1) can be used independently or as a mixture of two or more.

[0052] <<Dicarboxylic acid component (B2)>>

[0053] As the dicarboxylic acid component (B2), for example, at least one carboxylic acid selected from dicarboxylic acids having 4 to 36 carbon atoms can be used. As the above-mentioned dicarboxylic acids, for example, 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, dimer acid, etc. can be cited. Dimer acid is a polymerized fatty acid obtained by polymerizing (dimerizing) unsaturated fatty acids (for example, unsaturated fatty acids having 18 or 22 carbon atoms) obtained from vegetable oils such as soybean oil, tall oil, linseed oil, and cottonseed oil. Generally, dimer acids having 36 carbon atoms are commercially available. Among the commercially available dimer acids, monomeric acids and trimer acids are also included in addition to dimer acids, but those having a higher content of dimer acids are preferred. Each compound used as these dicarboxylic acid components (B2) can be used independently or in combination of two or more.

[0054] Here, in order to improve the viscosity imparting effect, pseudoplasticity imparting effect, and thermal stability effect of the aqueous coating composition containing the viscosity modifier of the present invention, the dicarboxylic acid component (B2) preferably contains at least a polymerized fatty acid. The polymerized fatty acid used as the dicarboxylic acid component (B2) of the present invention is a polymer obtained by polymerizing a monobasic fatty acid having an unsaturated bond, or a polymer obtained by polymerizing an ester of a monobasic fatty acid having an unsaturated bond. As a monobasic fatty acid having an unsaturated bond, an unsaturated fatty acid having 1 to 3 unsaturated bonds and a total carbon number of 8 to 24 is generally used. As these unsaturated fatty acids, for example, oleic acid, linoleic acid, linolenic acid, natural drying oil fatty acids, natural semi-drying oil fatty acids, etc. can be cited. In addition, as esters of monobasic fatty acids having unsaturated bonds, esters of monobasic fatty acids having the above unsaturated bonds and aliphatic alcohols, preferably aliphatic alcohols having 1 to 3 carbon atoms, can be cited. Among the polymerized fatty acids as described above, dimer acid is particularly preferred as the dicarboxylic acid component (B2).

[0055] <<Physical Properties of Polyamide Compound (B)>>

[0056] The acid value of the polyamide compound (B) of the present invention is preferably greater than or equal to 30 and less than or equal to 140. By making the acid value of the polyamide compound (B) within the above range, the viscosity modifier of the present invention can further improve the viscosity imparting effect and pseudoplasticity imparting effect on the water-based coating, and the effect of improving the thermal stability of the water-based coating. In addition, when the acid value of the polyamide compound (B) is less than 30, the hydrophobicity of the polyamide compound (B) is too high, so it is sometimes difficult to disperse it into the water-based coating composition. When the acid value is greater than 140, it is sometimes difficult to synthesize the polyamide.

[0057] Here, the acid value in this specification can be measured according to JIS K0070-1992. In addition, the acid value refers to the number of mg of potassium hydroxide required to neutralize the free fatty acids contained in 1 g of the sample. In addition, there are two methods for measuring the acid value: neutralization titration and potentiometric titration, but the acid value in this specification is the value measured by neutralization titration.

[0058] <Content ratio of diamide compound (A) and hydrogenated castor oil (A')>

[0059] In the viscosity imparting component (X) of the present invention, when the total amount of the viscosity imparting component (X) is 100 parts by mass, the total content of the diamide compound (A) and the hydrogenated castor oil (A') needs to be greater than or equal to 60 parts by mass. In addition, when the viscosity imparting component (X) contains a polyamide compound (B), it is preferred that the content of the polyamide compound (B) is less than or equal to 40 parts by mass. In other words, the ratio of the total content Q(A+A') of the diamide compound (A) and the hydrogenated castor oil (A') in the viscosity imparting component (X) to the content Q(B) of the polyamide compound (B) [Q(A+A'):Q(B)] is in the range of 60:40 to 100:0.

[0060] <Content of Viscosity Imparting Component (X)>

[0061] The content of the viscosity imparting component (X) in the viscosity modifier of the present invention is greater than or equal to 1 mass % and less than or equal to 30 mass %. When the content of the viscosity imparting component (X) is less than 1 mass %, it is possible that the viscosity imparting effect and pseudoplasticity imparting effect of the viscosity modifier on the aqueous coating composition cannot be obtained. On the other hand, when the content of the viscosity imparting component (X) is greater than 30 mass %, the dispersibility of the viscosity imparting component (X) in a medium mainly composed of water is reduced, and the anti-settling property and thermal stability of the aqueous coating composition are likely to deteriorate. From the viewpoint of improving anti-sagging property, it is preferred that the content of the viscosity imparting component (X) is greater than or equal to 3.0 mass % and less than or equal to 20.0 mass %, and more preferably greater than or equal to 3.0 mass % and less than or equal to 15.0 mass %.

[0062] (Alkali for neutralization (G))

[0063] Here, in the viscosity modifier of the present invention, the use of a neutralizing base such as an amine for dispersing the polyamide compound (B) in a medium mainly composed of water (i.e., as a hydrophilizing aid that helps the hydrophilization of the polyamide compound (B)) is not prohibited. However, as described above, when a neutralizing base is used, in a water-based epoxy primer (main agent) used in the field of anti-corrosion coatings, when a viscosity modifier containing a polyamide neutralized with an amine is added, there is a problem of gelation due to the reaction of the epoxy resin of the main agent with the amine used for neutralization, so it is preferred that the content of the neutralizing base (G) is as small as possible. From this point of view, for example, the content of the neutralizing base (G) is preferably less than or equal to 2% by mass in the viscosity modifier, and it is more preferred that the neutralizing base (G) is substantially not contained.

[0064] As such a neutralization base (G), any of an organic base and an inorganic base can be used. As an organic base, for example, alkylamines such as ethylamine, diethylamine, and triethylamine, and alcoholamines such as ethanolamine, diethanolamine, triethanolamine, and N,N'-dimethylethanolamine can be used. As an inorganic base, for example, sodium hydroxide, potassium hydroxide, ammonia, etc. can be used. These can be used independently or in combination.

[0065] (First Solvent (C))

[0066] The aqueous resin viscosity modifier of the present invention, in addition to the above-mentioned viscosity imparting component (X), also contains the first solvent (C) as an essential component. The first solvent (C) is used to make the viscosity imparting component (X) easily dispersed in a medium with water as the main body. In addition, the viscosity imparting component (X) can be mixed with the first solvent (C), and the mixture is heat-treated, so that the viscosity imparting effect and the pseudoplasticity imparting effect on the aqueous coating composition are manifested. That is, the first solvent (C) is used as an activation auxiliary agent that helps to impart the viscosity imparting effect and the pseudoplasticity imparting effect based on the viscosity imparting component (X) (activation of the viscosity imparting component (X)).

[0067] As the first solvent (C), a solvent having at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, an amide group, and a ketone group can be used. As examples of the first solvent (C), alcohol solvents, glycol ethers (ethers corresponding to the monomers of glycols) solvents, di(glycol) ethers (ethers corresponding to dimers formed by dehydration condensation of two molecules of glycols) solvents, tri(glycol) ethers (ethers corresponding to trimers formed by dehydration condensation of three molecules of glycols) solvents, ester solvents, and amide solvents can be cited. As alcohol solvents, for example, aliphatic alcohols such as methanol, ethanol, propanol, butanol, isobutanol, isopropanol, amyl alcohol, hexanol, heptanol, octanol, 2-ethylhexanol, and cyclic alcohols such as benzyl alcohol can be cited. As glycol ether solvents, for example, ethylene glycol monomethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether (2-ethylhexyl glycol; ethylene glycol mono-2-ethylhexyl ether), propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monophenyl ether (phenyl glycol), etc. As di(glycol) ether solvents, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, etc., can be mentioned. As tri(glycol) ether solvents, for example, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, etc., can be mentioned. As ester solvents, for example, dibasic esters such as methyl glutarate, methyl succinate, methyl adipate, and propylene glycol monomethyl ether acetate, amyl propionate, ethoxyethyl propionate, 2,2,4-trimethylpentanediol monoisobutyrate, etc. can be cited. As amide solvents, for example, non-cyclic amides such as dimethylformamide, diethylformamide, dimethylacetamide, 3-methoxy-N, N-dimethylpropionamide, hexamethylphosphoramide, and cyclic amides such as N-methylpyrrolidone can be cited. In addition, polyols such as ethylene glycol, propylene glycol, butylene glycol, glycerol, sorbitol, and xylitol can also be used as solvent (C). Solvents such as the above can be used alone or in combination.

[0068] In addition, from the viewpoint of further improving the effect of adding the first solvent (C) (effect of imparting viscosity, effect of imparting pseudoplasticity, etc.), it is preferable to use a solvent having an HLB value of 3 or more and 10 or less as the first solvent (C). Examples of such solvents include ethyl hexanol, butanol, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monophenyl ether, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, dipropylene glycol monobutyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol monobutyl ether, triethylene glycol monomethyl ether, 2,2,4-trimethylpentanediol monoisobutyrate, and propylene glycol monomethyl ether acetate. In addition, as the HLB value of the first solvent (C), a value calculated by the Davis method is used.

[0069] The content of the first solvent (C) in the viscosity modifier of the present invention is greater than or equal to 5% by mass and less than or equal to 99% by mass. When the content of the first solvent (C) is less than 5% by mass, it is possible that the viscosity modifier cannot impart viscosity and pseudoplasticity to the aqueous coating composition, and the effect of improving the thermal stability of the aqueous coating composition. On the other hand, the upper limit of the content of the first solvent (C) is not particularly limited, but in the viscosity modifier of the present invention, since it contains a viscosity imparting component (X) of greater than or equal to 1% by mass as an essential component, the content of the first solvent (C) is 99% by mass. From the viewpoint of improving thermal stability, the content of the first solvent (C) is preferably 10% to 99% by mass.

[0070] (Water(D))

[0071] The viscosity modifier of the present invention is for water-based resins, and is obtained by dispersing a viscosity-imparting component (X) as an effective ingredient in a medium mainly composed of water. As water (D), for example, ion-exchanged water can be used. Although water (D) is not an essential component of the viscosity modifier of the present invention (that is, water (D) may not be included in the viscosity modifier), the content of the first solvent (C) is preferably as little as possible in terms of the impact on the environment and the human body, and the content of the solvent (C) can be reduced by containing water (D). However, when the content of water (D) is too much, it may be impossible to contain the required amount of viscosity-imparting component (X) and solvent (C) in the viscosity modifier, and therefore, the content of water (D) is preferably less than or equal to 80% by mass relative to the total mass of the viscosity modifier.

[0072] (Surfactant (E))

[0073] The viscosity modifier of the present invention may also contain a surfactant (E) as an optional component. The surfactant (E) is used as a hydrophilizing aid for hydrophilizing the viscosity imparting component (X) so that the viscosity imparting component (X) is easily dispersed in a medium with water as the main component. Examples of the surfactant (E) include polyoxyethylene cured castor oil, polyoxyethylene castor oil, or polyoxyethylene stearyl ether, polyoxyethylene 2-ethylhexyl ether, polyoxyethylene styrenated phenyl ether and the like polyoxyethylene alkyl ethers, or polyoxyethylene cured castor oil monoisostearate, polyoxyethylene cured castor oil triisostearate, or polyoxyethylene glycerol fatty acid esters such as monoisostearate polyoxyethylene glyceryl ester, or polyoxyethylene sorbitan aliphatic esters such as monostearate polyoxyethylene sorbitan, or polyoxyethylene oxypropylene copolymers.

[0074] As the type of surfactant (E) used in the present invention, as long as it is a nonionic surfactant, it can show good anti-settling properties and thermal stability. However, from the viewpoint of further improving the addition effect of the surfactant (E) (the effect of facilitating the dispersion of the viscosity-imparting component (X)) and improving the anti-sagging property, as the surfactant (E), it is preferred to use a nonionic surfactant with an HLB value greater than or equal to 3 and less than or equal to 18.5. In addition, as the HLB value of the surfactant (E), it is set to use a value calculated by the Griffin method. Similarly, from the viewpoint of improving the anti-sagging property, as the surfactant (E), it is preferred to use a compound that does not contain an aromatic ring.

[0075] In addition, when the compounds exemplified above are used as surfactants (E), the number of added moles of ethylene oxide (EO) is preferably greater than or equal to 3 moles and less than or equal to 200 moles. Here, from the viewpoint of improving the anti-sagging property of the water-based paint containing the viscosity modifier of the present invention, the number of added moles of EO is more preferably greater than or equal to 10 moles and less than or equal to 200 moles, and further preferably greater than or equal to 10 moles and less than or equal to 100 moles. On the other hand, from the viewpoint of improving the temporal stability of the water-based paint containing the viscosity modifier of the present invention, the number of added moles of EO is more preferably greater than or equal to 10 moles and less than or equal to 200 moles.

[0076] The content of the surfactant (E) of the present invention is preferably less than or equal to 300 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A'). The addition effect of the surfactant (E) (the effect of easily dispersing the viscosity-imparting component (X)) can be further improved by making the content of the surfactant (E) within the above range. In particular, from the viewpoint of improving the time stability and anti-sagging properties of the coating, the content of the surfactant (E) is more preferably less than or equal to 200 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A'). From the viewpoint of particularly improving anti-sagging properties, the content of the surfactant (E) is more preferably greater than or equal to 40 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A').

[0077] (Second solvent (F))

[0078] The viscosity modifier of the present invention may also contain a second solvent (F) as an optional component. The second solvent (F) has the effect of improving the dispersibility of the viscosity modifier in the aqueous coating composition. As the second solvent (F), a solvent different from the first solvent (C) and having a relatively higher polarity than the first solvent (C) is used. As examples of such a second solvent (F), alcohols, polyols, glycol ethers, di(glycol) ethers, tri(glycol) ethers, etc. can be used. As alcohols, for example, aliphatic alcohols such as methanol, ethanol, propanol, butanol, isobutanol, isopropanol, pentanol, hexanol, heptanol, octanol, 2-ethylhexanol, or cyclic alcohols such as benzyl alcohol can be cited. As polyols, for example, ethylene glycol, propylene glycol, butylene glycol (butylene glycol), buthanediol, diethylene glycol, glycerol, sorbitol, xylitol, etc. can be cited. As glycol ethers, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisobutyl ether, ethylene glycol monohexyl ether, ethylene glycol mono-2-ethylhexyl ether, propylene glycol monomethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, ethylene glycol monophenyl ether, etc. can be mentioned. As di(glycol) ethers, for example, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monobutyl ether, etc. can be mentioned. As tri(glycol) ethers, for example, triethylene glycol monomethyl ether, triethylene glycol monobutyl ether, etc. can be mentioned.

[0079] The content of the second solvent (F) of the present invention is preferably less than or equal to 20% by mass relative to the total mass of the viscosity modifier. By making the content of the second solvent (F) within the above range, the addition effect of the second solvent (F) (the effect of improving the stability of the coating) can be further improved. From the viewpoint of particularly improving thermal stability, the content of the second solvent (F) is preferably less than or equal to 10% by mass. In addition, from the viewpoint of improving anti-settling properties, the content of the second solvent (F) is more preferably less than or equal to 10% by mass, and further preferably less than or equal to 5% by mass.

[0080] (Other additives)

[0081] The viscosity modifier for aqueous resin of the present invention may also contain auxiliary agents for the purpose of imparting other functions. For example, various auxiliary agents may be added for the purpose of maintaining the gloss of the coating film, improving the dispersibility of the pigment, the defoaming property of the aqueous coating composition, the flow surface, etc.

[0082] (Method for producing viscosity modifier)

[0083] For example, a viscosity modifier containing the above-mentioned components can be manufactured as follows. First, water (D) or a mixed solution in which the first solvent (C) or the second solvent (F) is mixed with water as required is cooled to prepare cold water or a cooled solution (hereinafter referred to as "cold water, etc."). At this time, the temperature of the cold water, etc. is not particularly limited, but, for example, can be set to about 5 to 15°C. On the other hand, a mixed solution of a viscosity-imparting component (X) and a first solvent (C) (and a surfactant (E) is further mixed as required) is prepared. The mixing conditions when preparing the mixed solution are not particularly limited, but since the mixing efficiency is improved when the components are in a dissolved state, the mixing is usually carried out at a temperature of 90 to 150°C. In the case where a polyamide compound (B) is included as the viscosity-imparting component (X), a neutralizing base (G) is added to the mixed solution to neutralize the polyamide compound (B).

[0084] Next, while stirring the cold water, the mixed solution prepared as described above is gradually added to the cold water, etc. Next, if necessary, a solution prepared by diluting the surfactant (E) with the first solvent (C) is added to the cold water, etc. to which the mixed solution has been added, to obtain an aqueous dispersion of the viscosity-imparting component (X).

[0085] After adding all the components, the dispersion obtained as described above is transferred to a container and the dispersion is subjected to a heating treatment. The heating treatment helps to form composite fibrous particles formed by the viscosity-imparting component (X) and the first solvent (C), and can improve the anti-settling effect. The heating temperature when the dispersion is subjected to a heating treatment is not particularly limited, but is preferably 45 to 90°C, and more preferably 50 to 90°C. In addition, the heating treatment time of the dispersion is not particularly limited, but is preferably 5 to 60 hours, and more preferably 10 to 48 hours.

[0086] (Application of viscosity modifier)

[0087] The viscosity modifier of the present invention is not particularly limited in its application as long as it is added to a water-based paint together with a water-based resin, but the viscosity modifier of the present invention can be preferably applied to a water-based metallic paint using an aluminum pigment or a pearl pigment such as mica, or a water-based anticorrosive paint using a pigment having a large particle system and a large specific gravity such as an anticorrosive pigment, etc. In addition, the viscosity modifier of the present invention can also be preferably applied to a water-based paint using a common coloring pigment and a extender pigment other than the above, or a water-based paint such as a water-based ink, etc.

[0088] [Water-based coating composition]

[0089] The water-based coating composition of the present invention contains a water-based resin, a pigment, and the above-mentioned viscosity modifier for the water-based resin as essential components. In addition, the water-based coating composition of the present invention may further contain other additives such as a defoamer, a film-forming aid, and a pH adjuster as optional components.

[0090] (Content of viscosity modifier)

[0091] The viscosity modifier for aqueous resin of the present invention varies depending on the type of aqueous resin as a binder in the aqueous coating composition, the composition of pigments, etc., but is generally contained in an amount of 0.1 mass % or more and 1.0 mass % or less of the viscosity imparting component (X) relative to the total solid content of the aqueous coating composition. By making the content of the viscosity modifier within the above range, the effect of adding the viscosity modifier (the effect of imparting viscosity and pseudoplasticity to the aqueous coating composition, and the effect of improving the thermal stability of the aqueous coating composition) can be further improved.

[0092] (Water-based resin)

[0093] The water-based resin contained in the water-based coating composition of the present invention as a bonding agent is a resin component dispersed in a medium with water as the main body. As a resin component, for example, acrylic resin, acrylic silicone resin, alkyd resin, polyester resin, polyurethane resin, epoxy resin, silicone resin, fluororesin, etc. can be enumerated. As the form of water-based resin, it is divided into water-soluble, colloidal dispersion, latex according to the dispersion mode, but can be adapted to any form. These resins can be, for example, heat-cured, ultraviolet-cured, electron-beam-cured, oxidative-cured, photocation-cured, peroxide-cured, and resins cured with chemical reactions in the presence or absence of catalysts, or resins with high glass transition points and not accompanied by chemical reactions and only by volatilizing the diluent to become coated films. In addition, as a curing agent, for example, amino resins, melamine resins, isocyanate compounds, blocked isocyanate compounds, and epoxy compounds, etc. can be enumerated.

[0094] (pigment)

[0095] As pigments, for example, body pigments, coloring pigments and metallic pigments can be cited. As body pigments, for example, calcium carbonate (heavy calcium carbonate (GCC), precipitated calcium carbonate (PCC), etc.), barium sulfate, silicon dioxide, aluminum hydroxide, talc, mica, organic fiber, glass powder, etc. can be used. As coloring pigments, for example, titanium dioxide, carbon black, chrome yellow, cadmium yellow, ochre, titanium yellow, zinc chromate, red iron oxide, aluminosilicate, quinacridone, phthalocyanine, anthraquinone, pyrrolopyrrole dione, benzimidazolone and isoindolinone can be used. As metallic pigments, for example, aluminum flake powder, copper flake powder, mica-like iron oxide, mica and flaky powders with metal oxides on mica can be used.

[0096] (Other additives)

[0097] The aqueous coating composition of the present invention may contain other substances, for example, dehydrating agents (for example, silane coupling agents), adhesion promoters, surfactants, curing catalysts, film-forming aids, desiccants, antifouling agents, sensitizers, antioxidants, light stabilizers, ultraviolet absorbers, water-resistant agents, preservatives and mildew preventers, defoaming agents, leveling agents, dispersants, flame retardants, antistatic agents, stripping agents, deodorants, pH adjusters, fragrances and other additives, within the scope of not impairing its characteristics and the purpose of the present invention.

[0098] (Method for producing water-based coating composition)

[0099] The water-based coating composition of the present invention can be manufactured according to a known method for manufacturing water-based coatings. For example, after the above-mentioned viscosity modifier and components other than the pigment are mixed while stirring in a medium mainly composed of water such as ion-exchanged water, pH adjustment is performed as required to prepare a clear coating. The water-based coating composition can be manufactured by adding a viscosity modifier and a pigment to the clear coating and dispersing them in the clear coating.

[0100] In addition, for example, when manufacturing a two-component water-based epoxy coating, the above-mentioned components other than the viscosity modifier are mixed while stirring in a medium mainly composed of water such as ion-exchanged water, and an epoxy main agent is prepared. The viscosity modifier is added to the epoxy main agent and dispersed in the epoxy main agent to prepare an epoxy main agent containing the viscosity modifier. Next, the epoxy main agent prepared in this way is mixed with a curing agent such as an amine curing agent to manufacture a water-based epoxy coating.

[0101] In the past, since there was no viscosity modifier that could exert viscosity imparting effects, pseudoplasticity imparting effects, thermal stability effects, etc. in a wide range of pH from acidic to alkaline, the viscosity modifier was limited to being added to the amine curing agent side. This is because, in the case of adding the viscosity modifier to the amine curing agent side, the amine curing agent is alkaline, and the waterborne epoxy coating also maintains alkalinity after mixing with the epoxy main agent, so it is difficult to be affected by pH changes. However, according to the viscosity modifier of the present invention, since it can exert viscosity imparting effects, pseudoplasticity imparting effects, thermal stability effects, etc. in a wide range of pH from acidic to alkaline, it is possible to add the viscosity modifier to the epoxy main agent side.

[0102] Here, since the viscosity of the amine curing agent itself is high, when the viscosity modifier is added to the amine curing agent side, the curing agent further thickens, and the handling property of the liquid is reduced. On the other hand, the viscosity of the epoxy main agent is not higher than that of the amine curing agent, so even if the viscosity modifier is added and the curing agent thickens, there is no disadvantage such as reduced handling property as in the case of adding the viscosity modifier to the amine curing agent side. On the contrary, by adding the viscosity modifier to the epoxy main agent side, the amine curing agent with high viscosity does not thicken, while the epoxy main agent with relatively low viscosity thickens, so the viscosity difference between the epoxy main agent and the amine curing agent becomes smaller than in the case of adding the viscosity modifier to the amine curing agent side. In this way, when the epoxy main agent and the amine curing agent are mixed, the viscosity difference between the two mixed liquids becomes smaller, so it is easy to mix the epoxy main agent and the amine curing agent.

[0103] In addition, as the time to add the viscosity modifier of the present invention to the water-based paint, it can be either in the process of kneading the pigment as described above, or it can be added after the water-based paint is manufactured, and further, a master batch can be prepared for addition. In addition, the equipment used for dispersing the viscosity modifier and the pigment can use the equipment commonly used in the manufacture of water-based paint. Furthermore, the stirring speed and stirring time conditions during the dispersion of the viscosity modifier and the pigment are not particularly limited, and can be appropriately set while confirming the dispersion state of the viscosity modifier and the pigment.

[0104] (Application of water-based coating composition)

[0105] The water-based coating composition of the present invention can be suitably used for water-based metallic coatings using aluminum pigments or pearl pigments such as mica, or water-based anticorrosive coatings using pigments with large particles and large specific gravity such as anticorrosive pigments, etc. In addition, the water-based coating composition of the present invention can be suitably used as water-based coatings using common coloring pigments or extender pigments other than the above, or water-based coatings such as water-based inks, etc.

[0106] The preferred embodiments of the present invention are described above, but the present invention is not limited to the above-mentioned embodiments. That is, other embodiments or various modifications that can be thought of by those skilled in the art within the scope of the invention described in the claims are also understood to belong to the technical scope of the present invention.

[0107] [Example]

[0108] Hereinafter, the present invention will be specifically described with reference to Examples. In addition, the present invention is not limited to these Examples. In addition, "%" and "part" in the Examples represent "mass %" and "mass part" unless otherwise specified.

[0109] [Synthesis of diamide compound (A)]

[0110] As described in detail below, the diamine component (A1) and the monocarboxylic acid (A2) described in Table 1 were reacted at the ratio (molar ratio) shown in Table 1 to obtain the diamide compounds (A) of Synthesis Examples A-1 to A-6.

[0111] (Synthesis Example A-1)

[0112] In a 1-liter four-necked flask equipped with a stirring device, a temperature regulator, a water separator, and a nitrogen inlet tube, 298.6 parts (0.96 mol) of 12-hydroxystearic acid were measured and dissolved by heating at 80° C. Next, 55.8 parts (0.48 mol) of hexamethylenediamine were gradually added to the four-necked flask, and then a dehydration reaction was carried out at 185° C. for 5 hours to obtain the diamide compound (A) of Synthesis Example A-1 described in Table 1.

[0113] (Synthesis Examples A-2 to A-6)

[0114] Diamide compounds (A) of Synthesis Examples A-2 to A-6 were obtained in the same manner as Synthesis Example A-1 except that the components listed in Table 1 were used as the diamine component (A1) and the monocarboxylic acid (A2) and these were reacted in the ratios listed in Table 1.

[0115]

Table 1

[0116] Table 1 Formula of diamide compound (A)

[0117]

[0118] [Synthesis of polyamide compound (B)]

[0119] As described in detail below, the diamine component (B1) and the dicarboxylic acid (B2) described in Table 2 were reacted at the ratio (molar ratio) shown in Table 2 to obtain the polyamide compounds (B) of Synthesis Examples B-1 to B-10.

[0120] (Synthesis Example B-1)

[0121] In a 1-liter four-necked flask equipped with a stirring device, a temperature regulator, a water separator, and a nitrogen inlet tube, 354 parts (0.60 mol) of dimer acid (trade name "haridimer 250": manufactured by Harima Chemicals Co., Ltd.) and 53.1 parts (15% of the total carboxylic acid) of xylene were measured and heated to 50°C. Next, 34.9 parts (0.30 mol) of hexamethylenediamine were gradually added to the four-necked flask, and then stirred at 150°C for 60 minutes. After stirring, the mixture was further slowly heated to 175°C and a dehydration reaction was performed for 150 minutes to obtain a polyamide compound (B) of Synthesis Example B-1 described in Table 2.

[0122] (Synthesis Examples B-2 to B-10)

[0123] Polyamide compounds (B) of Synthesis Examples B-2 to B-10 were obtained in the same manner as Synthesis Example B-1, except that the components listed in Table 2 were used as the diamine component (B1) and the dicarboxylic acid (B2) and these were reacted in the ratios listed in Table 2.

[0124] The acid values ​​of the polyamide compounds (B) of Synthesis Examples B-1 to B-10 obtained as described above were measured. Specifically, the acid values ​​of the polyamide compounds (B) of Synthesis Examples B-1 to B-10 were measured by a neutralization titration method according to JIS K0070-1992. Table 2 shows the results.

[0125]

Table 2

[0126] Table 2 Formulation of polyamide compound (B)

[0127]

[0128] [Manufacture of viscosity modifier]

[0129] As described in detail below, the components described in Tables 3 to 6 were blended in the proportions (parts by mass) shown in Tables 3 to 6, and the aqueous resin viscosity modifiers of Production Examples S1 to S83 were obtained by heating the components at the heating treatment temperatures shown in Tables 3 to 6. In addition, the components described in Table 7 were blended in the proportions (parts by mass) shown in Table 7, and the aqueous resin viscosity modifiers of Comparative Production Examples H1 to H11 were obtained by heating the components at the heating treatment temperatures shown in Table 7.

[0130] (Manufacturing Example S1)

[0131] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 96 parts of ion exchange water as water (D) and 10 parts of ethylene glycol as a second solvent (F) were measured and cooled to 10°C to prepare cold water. On the other hand, 10 parts of diamide of Synthesis Example A-1 as diamide compound (A) and 76 parts of ethylene glycol monobutyl ether as a first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Next, the mixed solution was gradually added to the stirred cold water. Next, 4 parts of polyoxyethylene hydrogenated castor oil (trade name "blaunon CW-10", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as a surfactant (E) was prepared as a 50% solution in 4 parts of ethylene glycol monobutyl ether as a first solvent (C), and the 50% solution was gradually added to the cold water to which the mixed solution was added. After all the 50% solution was added, the obtained dispersion was transferred to a container and heated in a thermostatic bath at 80° C. for 24 hours to obtain a viscosity adjuster of Production Example S1 shown in Table 3.

[0132] (Manufacturing Examples S2 to S8, S71 to S83)

[0133] The viscosity adjusters of Manufacturing Examples S2 to S8 and S71 to S83 were obtained in the same manner as Manufacturing Example S1, except that the components listed in Table 3 or Table 6 were used as the viscosity adjusters, these components were added in the proportions listed in Table 3 or Table 6, and the heating treatment was performed at the heating treatment temperature shown in Table 3 or Table 6.

[0134] (Production Example S9)

[0135] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 100 parts of ion exchange water as water (D) was measured and cooled to 10°C to prepare cold water. On the other hand, 14 parts of diamide of Synthesis Example A-1 as diamide compound (A), 6 parts of polyamide of Synthesis Example B-1 as polyamide compound (B), 4 parts of polyoxyethylene-cured castor oil (trade name "blaunon CW-10", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as surfactant (E), and 74.8 parts of ethylene glycol monobutyl ether as the first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Then, 1.2 parts of N,N'-dimethylethanolamine as a neutralizing base (G) was added to the mixed solution and mixed. Next, the mixed solution was gradually added to the stirred cold water. After all the addition was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 80° C. for 24 hours, thereby obtaining a viscosity adjuster of Production Example S9 shown in Table 3.

[0136] (Manufacturing Examples S10 to S19, S48 to S51)

[0137] The viscosity adjusters of Manufacturing Examples S10 to S19 and S48 to S51 were obtained in the same manner as Manufacturing Example S9, except that the components listed in Table 3 or Table 4 were used as the viscosity adjusters, these components were added in the proportions listed in Table 3 or Table 4, and the heating treatment was performed at the heating treatment temperature shown in Table 3 or Table 4.

[0138] (Manufacturing Example S20)

[0139] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 40 parts of ion exchange water as water (D) and 57.6 parts of ethylene glycol monobutyl ether as the first solvent (C) were measured and cooled to 10°C to prepare cooling water. On the other hand, 6 parts of diamide of Synthesis Example A-1 as diamide compound (A) and 91.6 parts of ethylene glycol monobutyl ether as the first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Next, the mixed solution was gradually added to the stirred cold water. Next, 2.4 parts of polyoxyethylene hydrogenated castor oil (trade name "blaunon CW-10", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as a surfactant (E) was prepared as a 50% solution in 2.4 parts of ethylene glycol monobutyl ether as the first solvent (C), and the 50% solution was gradually added to the cold water to which the mixed solution was added. After all the addition was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 75° C. for 24 hours, thereby obtaining a viscosity adjuster of Production Example S20 shown in Table 3.

[0140] (Manufacturing Examples S21 to S23)

[0141] The viscosity adjusters of Manufacturing Examples S21 to S23 were obtained in the same manner as Manufacturing Example S20, except that the components listed in Table 3 were used as the viscosity adjusters, these components were added in the ratios listed in Table 3, and the heating treatment was performed at the heating treatment temperature shown in Table 3.

[0142] (Manufacturing Example S24)

[0143] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 100 parts of 2-ethylhexanol as a first solvent (C) were measured and cooled to 10°C as a cold solvent. On the other hand, 10 parts of diamide of Synthesis Example A-1 as a diamide compound (A) and 90 parts of 2-ethylhexanol as a first solvent (C) were mixed and heated to 120°C to form a mixed solution. Next, the mixed solution was gradually added to the stirred cold solvent. After all the additions were completed, the obtained dispersion was transferred to a container and heated in a thermostatic bath at 85°C for 24 hours to obtain the viscosity modifier of Manufacturing Example S24 shown in Table 4.

[0144] (Manufacturing Examples S25 to S39)

[0145] The viscosity adjusters of Manufacturing Examples S25 to S39 were obtained in the same manner as Manufacturing Example S24, except that the components listed in Table 4 were used as the viscosity adjusters, these components were added in the ratios listed in Table 4, and the heating treatment was performed at the heating treatment temperature shown in Table 4.

[0146] (Manufacturing Example S40)

[0147] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 100 parts of ion exchange water as water (D) are measured and cooled to 10°C as cooling water. On the other hand, 10 parts of diamide of Synthesis Example A-1 as a diamide compound (A) and 90 parts of dipropylene glycol monobutyl ether as a first solvent (C) are mixed and heated to 120°C as a mixed solution. Next, the mixed solution is gradually added to the above-mentioned cold water being stirred. After the addition is completed, the obtained dispersion is transferred to a container, and the viscosity adjuster of Manufacturing Example S40 shown in Table 4 is obtained by heating it in a thermostatic bath at 80°C for 24 hours.

[0148] (Manufacturing Examples S41 to S47)

[0149] The viscosity adjusters of Manufacturing Examples S41 to S47 were obtained in the same manner as Manufacturing Example S40, except that the components listed in Table 4 were used as the viscosity adjusters, these components were added in the ratios listed in Table 4, and the heating treatment was performed at the heating treatment temperature shown in Table 4.

[0150] (Manufacturing Example S52)

[0151] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 96 parts of ion exchange water as water (D) were measured and cooled to 10°C to prepare cooling water. On the other hand, 10 parts of diamide of Synthesis Example A-1 as diamide compound (A) and 86 parts of ethylene glycol monobutyl ether as the first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Next, the mixed solution was gradually added to the stirred cold water. Next, 4 parts of polyoxyethylene castor oil (trade name "blaunon BR-410", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as a surfactant (E) was prepared as a 50% solution of 4 parts of ethylene glycol monobutyl ether as the first solvent (C), and the 50% solution was gradually added to the cold water to which the mixed solution was added. After all the addition was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 80° C. for 24 hours, thereby obtaining a viscosity adjuster of Production Example S52 shown in Table 5.

[0152] (Manufacturing Examples S53 to S70)

[0153] The viscosity adjusters of Manufacturing Examples S53 to S70 were obtained in the same manner as Manufacturing Example S52, except that the components listed in Table 5 were used as the viscosity adjusters, these components were added in the ratios listed in Table 5, and the heating treatment was performed at the heating treatment temperature shown in Table 5.

[0154]

[0155]

[0156]

[0157]

Table 6

[0158] Table 6 Viscosity modifier formulation (Manufacturing Example 4)

[0159]

[0160] (Comparative Manufacturing Example H1)

[0161] As the viscosity modifier of Comparative Production Example H1 shown in Table 7, a commercially available polyurethane thickener (trade name "ACRYSOL TM RM-2020", manufactured by Dow Chemical Company).

[0162] (Comparative Production Example H2)

[0163] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 156.6 parts of ion exchange water as water (D) were measured and heated to 40°C to form warm water. On the other hand, 21.0 parts of the polyamide of Synthesis Example B-3 as the polyamide compound (B), 2.0 parts of the diamide of Synthesis Example A-1 as the diamide compound (A), 7.0 parts of hydrogenated castor oil, and 10.6 parts of propylene glycol monomethyl ether as the first solvent (C) were mixed and heated to 120°C to form a mixed solution. Thereafter, 2.8 parts of N,N'-dimethylethanolamine as a neutralizing base (G) were added to the mixed solution and mixed. Next, the mixed solution was gradually added to the above-mentioned warm water being stirred. After all the additions were completed, stirring was continued for ten minutes at a temperature range of 40 to 50°C to obtain a dispersion in order to completely disperse. After the stirring was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 75° C. for 20 hours, thereby obtaining a viscosity adjuster of Comparative Production Example H2 shown in Table 7.

[0164] (Comparative Manufacturing Examples H3 and H4)

[0165] The viscosity adjusters of Comparative Manufacturing Examples H3 and H4 were obtained in the same manner as Comparative Manufacturing Example H2, except that the components listed in Table 7 were used as the viscosity adjusters, these components were added in the ratios listed in Table 7, and the heating treatment was performed at the heating treatment temperature shown in Table 7.

[0166] (Comparative Manufacturing Example H5)

[0167] The diamide of Synthesis Example A-1 was micronized by a pulverizer to obtain a micronized diamide compound with an average particle size of 10 μm. 126.0 parts of butyl acetate (BAC), 54 parts of an alcoholic mixed solvent with a proprietary alcohol as the main agent, and 20 parts of the micronized diamide of Synthesis Example A-1 were added to a closed container for heating treatment, and the suspension was obtained by fully dispersing it at a temperature of 20 to 25°C. The closed container containing the suspension was allowed to stand for 48 hours in a thermostatic bath pre-set at 65°C, and then allowed to stand at room temperature for cooling, to obtain the viscosity adjuster of Comparative Manufacturing Example H5 shown in Table 7.

[0168] (Comparative Manufacturing Example H6)

[0169] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 96 parts of ion exchange water as water (D) and 10 parts of ethylene glycol as a second solvent (F) were measured and cooled to 10°C to prepare cooling water. On the other hand, 10 parts of diamide of Synthesis Example A-4 as diamide compound (A) and 76 parts of ethylene glycol monobutyl ether as a first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Next, the mixed solution was gradually added to the stirred cold water. Next, 4 parts of polyoxyethylene hydrogenated castor oil (trade name "blaunon CW-10", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as a surfactant (E) was prepared as a 50% solution in 4 parts of ethylene glycol monobutyl ether, and the 50% solution was gradually added to the cold water to which the mixed solution was added. After all the addition was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 80° C. for 24 hours, thereby obtaining a viscosity adjuster of Comparative Production Example H6 shown in Table 7.

[0170] (Comparative Manufacturing Examples H7 and H8)

[0171] The viscosity adjusters of Comparative Manufacturing Examples H7 and H8 were obtained in the same manner as Comparative Manufacturing Example H6, except that the components listed in Table 7 were used as the viscosity adjusters, these components were added in the ratios listed in Table 7, and the heating treatment was performed at the heating treatment temperature shown in Table 7.

[0172] (Comparative Production Example H9)

[0173] In a 500 ml four-necked flask equipped with a stirring device, a cooling tube, and a thermometer, 100 parts of ion exchange water as water (D) were measured and cooled to 10°C to prepare cooling water. On the other hand, 10 parts of diamide of Synthesis Example A-1 as diamide compound (A), 10 parts of polyamide of Synthesis Example B-1 as polyamide compound (B), 4 parts of polyoxyethylene-cured castor oil (trade name "blaunon CW-10", manufactured by Aoki Oil & Fats Co., Ltd.) with an HLB of 6.4 as surfactant (E), and 74 parts of ethylene glycol monobutyl ether as the first solvent (C) were mixed and heated to 120°C to prepare a mixed solution. Then, 2.0 parts of N,N'-dimethylethanolamine as a neutralizing base (G) was added to the mixed solution and mixed. Next, the mixed solution was gradually added to the above-mentioned cold water under stirring. After all the addition was completed, the obtained dispersion was transferred to a container and subjected to a heating treatment in a thermostatic bath at 80° C. for 24 hours, thereby obtaining a viscosity adjuster of Comparative Production Example H9 shown in Table 7.

[0174] (Comparative Manufacturing Examples H10 and H11)

[0175] The viscosity adjusters of Comparative Manufacturing Examples H10 and H11 were obtained in the same manner as Comparative Manufacturing Example H9, except that the components listed in Table 7 were used as the viscosity adjusters, these components were added in the ratios listed in Table 7, and the heating treatment was performed at the heating treatment temperature shown in Table 7.

[0176]

Table 7

[0177] Table 7 Viscosity modifier formulation (comparative manufacturing example)

[0178]

[0179] In addition, the details of the first solvent (C), the surfactant (E), the second solvent (F), and the neutralization base (G) used in the above-mentioned Production Examples and Comparative Production Examples are shown in the following Tables 8 to 11.

[0180]

Table 8

[0181] Table 8: First solvent (C)

[0182]

[0183] * Calculated by Davis-Family

[0184]

Table 9

[0185] Table 9: Surfactant (E)

[0186]

[0187] *Manufacturer catalog value (Griffin method)

[0188]

Table 10

[0189] Table 10: Second solvent (F)

[0190] abbreviation composition Classification EtOH Ethanol alcohol EG Ethylene glycol Polyol (divalent) PG Propylene glycol Polyol (divalent) 1,3-BG 1,3-Butanediol Polyol (divalent) DEG Diethylene glycol Polyol (divalent) Glycerin glycerin Polyol (trivalent) MFG Propylene glycol monomethyl ether Glycol Ethers ECS Ethylene glycol monoethyl ether Glycol Ethers BDG Diethylene glycol monobutyl ether Di(diol)ether MFDG Dipropylene glycol monomethyl ether Di(diol)ether EDG Diethylene glycol monoethyl ether Di(diol)ether

[0191]

Table 11

[0192] Table 11: Neutralizing Base (G)

[0193] abbreviation composition Classification DMEA N,N-Dimethylethanolamine Alkylamine TEA Triethylamine Alkylamine

[0194] [Manufacturing of water-based coating composition]

[0195] Using the viscosity modifiers of the manufacturing examples S1 to S83 obtained as described above, the water-based coating compositions of Examples 1 to 95 were prepared using the types of viscosity modifiers and the evaluation formulas of the coatings shown in Tables 12 to 16. In addition, using the viscosity modifiers of the comparative manufacturing examples H1 to H11 obtained as described above, the water-based coating compositions of Comparative Examples 1 to 21 were prepared using the types of viscosity modifiers and the evaluation formulas of the coatings shown in Table 17. Furthermore, using the viscosity modifiers of the comparative manufacturing examples H2 to H4 obtained as described above, the water-based coating compositions of Reference Examples 1 to 3 were prepared. In addition, in the test examples 1 to 4 described later, water-based coating compositions (blank 1, blank 1b, blank 2, blank 3) not containing a viscosity modifier were also prepared (refer to Tables 17 and 18).

[0196]

[0197]

[0198]

[0199]

Table 15

[0200] Table 15: Formulation and evaluation results of waterborne coating composition (Example 4)

[0201]

[0202]

Table 16

[0203] Table 16: Formulation and evaluation results of waterborne coating composition (Example 5)

[0204]

[0205]

[0206]

Table 18

[0207] Table 18: Formulation and evaluation results of water-based coating compositions (reference example)

[0208]

[0209] [Evaluation method of water-based coating composition]

[0210] For the water-based coating compositions of Examples 1 to 95, Comparative Examples 1 to 21, and Reference Examples 1 to 3 obtained as described above, various performance tests (Test Examples 1 to 4) were performed as follows. In addition, for the method of the performance test, the evaluation formula of the coating for each water-based coating composition (the composition of the coating to be evaluated) was classified and described in detail below. In addition, in the following Test Examples 1 and 2, the "main agent" of the water-based two-component epoxy coating refers to the liquid agent containing the pigment of the two liquid agents before the main agent is cured, and the "curing agent" refers to the agent that does not contain the pigment.

[0211] (Test Example 1: Evaluation of the Aqueous Coating Composition Prepared Using Evaluation Formula 1)

[0212] In Test Example 1, the performance test of the viscosity modifier was conducted using the aqueous two-component epoxy coating formulation (Evaluation Formulation 1) shown in Table 19 as an evaluation formulation.

[0213]

Table 19

[0214] Table 19: Evaluation formula 1 (water-based two-component epoxy coating formula)

[0215]

[0216] a=0.6% by mass

[0217] (Active ingredient conversion)

[0218]

[0219] Ratio: Epoxy / Amine = 1 / 0.8

[0220] As shown in Table 19, 49.14 parts of JR-600A (manufactured by Imperial Chemical Industry (TAYCA) Co., Ltd.) as a coloring pigment (titanium white), 34.02 parts of K-WHITE 140W (manufactured by Imperial Chemical Industry (TAYCA) Co., Ltd.) as a rust-proof pigment, 100.17 parts of barium sulfate (manufactured by Sakai Chemical Co., Ltd.) and 43.47 parts of talc No. 1 (manufactured by Takehara Chemical Industry Co., Ltd.) as an extender were stirred and mixed using a laboratory disperser, and then 206.64 parts of jER W1155R55 (manufactured by Mitsubishi Chemical Corporation) and 57.33 parts of jER W3435 R67 (manufactured by Mitsubishi Chemical Corporation) as epoxy resins and 37.80 parts of ethylene glycol monobutyl ether as a film-forming aid were added to prepare an epoxy main agent. 0.6 mass % (calculated as the mass of the viscosity imparting component (X) as an effective component) of any viscosity modifier of Preparation Examples S20 to S23, S43, S52 to S70 and Comparative Preparation Examples H1 to H5 was added to the epoxy main agent, and the mixture was stirred at room temperature using a laboratory disperser. The dispersion was performed at a rotation speed of 2000 rpm for 10 minutes to produce the water-based coating compositions of Examples 20 to 23, 53 to 72 and Comparative Examples 1 to 5 (before mixing with a curing agent).

[0221] <Evaluation of Anti-settling Property and Thermal Stability>

[0222] The aqueous coating composition prepared as described above (before mixing with the curing agent) was transferred to a 50 mL glass bottle and allowed to stand in a thermostatic chamber at 25°C and 60°C for 7 days. The degree of pigment agglomeration in the coating (before mixing with the curing agent) was compared with that in blank (epoxy main agent without viscosity modifier) ​​using a spatula, and the anti-settling property was evaluated using the following criteria.

[0223] (Evaluation Criteria)

[0224] A: Pigment is well dispersed (same as blank)

[0225] B: The transparent layer is slightly separated (re-dispersed by re-stirring to return to the state at the time of production)

[0226] C: Soft agglomerates (re-disperse by re-stirring to return to the state at the time of production)

[0227] D: Change of state or agglomeration occurs (even if stirred again, it cannot return to the original state).

[0228] D: Pigments are unevenly distributed or separated

[0229] In addition, the thermal stability was evaluated according to the following criteria based on the difference between the evaluation of the anti-settling property when stored at 25°C and the evaluation of the anti-settling property when stored at 60°C.

[0230] (Evaluation Criteria)

[0231] A: The evaluation of anti-settling properties at 25°C and 60°C is the same

[0232] (All are judged as A, All are judged as B, All are judged as C)

[0233] B: There is a one-level difference in the evaluation of anti-settling properties at 25°C and 60°C

[0234] (A judgment and B judgment, B judgment and C judgment, C judgment and D judgment)

[0235] C: There is a difference of two levels in the evaluation of anti-settling properties at 25°C and 60°C

[0236] (A judgment and C judgment, B judgment and D judgment)

[0237] D: There are three levels of difference in the evaluation of anti-settling properties at 25°C and 60°C

[0238] (A judgment and D judgment)

[0239] D: Unable to determine

[0240] (The evaluation of the anti-settling property at 25°C and the anti-settling property at 60°C were both rated D)

[0241] <Evaluation of coating stability over time>

[0242] On the day when the water-based coating composition (before the curing agent is mixed) is prepared as described above, the viscosity (mPa·s) at 60rpm and the viscosity (mPa·s) at 6rpm are measured at 25°C using a B-type viscometer, and the TI value (viscosity at 6rpm / viscosity at 60rpm) is calculated. In addition, after the above-mentioned water-based coating composition (before the curing agent is mixed), it is left to stand in a 25°C constant temperature bath for four weeks, and the viscosity (mPa·s) at 60rpm and the viscosity (mPa·s) at 6rpm are measured at 25°C on the next day of preparation and once a week from the preparation, and the TI value (viscosity at 6rpm / viscosity at 60rpm) is calculated. Further, according to the value of the viscosity change rate calculated by the following formula, the time stability of the coating is evaluated using the following benchmark. In addition, for Comparative Example 5, since poor dispersion in the coating and uneven coating were confirmed by visual observation, the evaluation of time stability was terminated the next day after the epoxy main agent was prepared.

[0243] Viscosity change rate = (viscosity at 60 rpm four weeks after production / viscosity at 60 rpm on the day of production) × 100

[0244] (Evaluation Criteria)

[0245] A: Viscosity change rate is less than 168% (same as blank)

[0246] B: Viscosity change rate is greater than or equal to 168% and less than 190%

[0247] C: Viscosity change rate is greater than or equal to 190% and less than 220%

[0248] D: Viscosity change rate is greater than or equal to 220%

[0249] <Evaluation of Anti-Sagging Property>

[0250] As shown in Table 19, 100.00 parts of the aqueous coating composition prepared as described above (before mixing the curing agent) were mixed with 23.50 parts of jER WD11M60 (manufactured by Mitsubishi Chemical Corporation) as an amine curing agent to prepare an aqueous coating composition (waterborne epoxy coating). After the main agent and the curing agent were mixed, the mixture was diluted with ion exchange water so that the viscosity measured by a B-type viscometer became 20P (25°C), and the anti-sagging property was measured using a tester. Based on the measured value, the anti-sagging property was evaluated using the following benchmark. In addition, for Comparative Example 5, poorly dispersed materials in the coating were confirmed by visual observation and the coating was uneven, so the anti-sagging property was not evaluated.

[0251] (Evaluation Criteria)

[0252] A: The measured value is greater than or equal to 450μm

[0253] B: The measured value is greater than or equal to 400μm and less than 450μm

[0254] C: The measured value is greater than 300μm and less than 400μm

[0255] D: The measured value is less than or equal to 300μm (equivalent to blank)

[0256] (Test Example 2: Evaluation of an aqueous coating composition prepared using Evaluation Formulation 1b)

[0257] In Test Example 2, the performance test of the viscosity modifier was conducted using the water-based two-component epoxy paint formulation (evaluation formulation 1b) shown in Table 20 as an evaluation formulation.

[0258]

Table 20

[0259] Table 20: Evaluation formula 1b (water-based two-component epoxy coating formula)

[0260]

[0261] a=0.6% by mass

[0262] (Active ingredient conversion)

[0263]

[0264]

[0265] Ratio: Epoxy / Amine = 1 / 0.8

[0266] As shown in Table 20, 66.30 parts of JR-600A (manufactured by Imperial Chemical Industry (TAYCA) Co., Ltd.) as a coloring pigment (titanium white), 45.90 parts of K-WHITE 140W (manufactured by Imperial Chemical Industry (TAYCA) Co., Ltd.) as a rust-proof pigment, 135.15 parts of barium sulfate (manufactured by Sakai Chemical Co., Ltd.) and 58.65 parts of talc No. 1 (manufactured by Takehara Chemical Industry Co., Ltd.) as an extender were stirred and mixed using a laboratory disperser, and then 199.75 parts of jER WD11M60 (manufactured by Mitsubishi Chemical Corporation) as an amine were added to prepare an amine main agent. 0.6 mass % (based on the mass of the viscosity imparting component (X) as an active ingredient) of any of the viscosity modifiers in Preparation Examples S21, S43, S52, S53, S58, S63, S64, S66, S69, S70 and Comparative Preparation Examples H2 to H4 was added to the amine main agent, and the mixture was stirred for 2 hours using a laboratory disperser. The dispersion was performed at a rotation speed of 2000 rpm for 10 minutes to prepare water-based coating compositions of Examples 86 to 95 and Reference Examples 1 to 3 (before mixing with a curing agent).

[0267] As shown in Table 20, 170.56 parts of jER W1155R55 (manufactured by Mitsubishi Chemical Corporation) and 47.32 parts of jER W3435R67 (manufactured by Mitsubishi Chemical Corporation) as epoxy resins and 31.20 parts of ethylene glycol monobutyl ether as a film-forming aid were stirred and mixed using a laboratory disperser to prepare an epoxy curing agent.

[0268] <Evaluation of Anti-settling Property and Thermal Stability>

[0269] The water-based coating composition prepared as described above (before mixing with the curing agent) was transferred to a 50 mL glass bottle and left to stand in a thermostatic chamber at 25°C and 60°C for 7 days, and the percentage of the volume of the settled pigment (Iriodin) relative to the total volume of the coating (hereinafter referred to as "sedimentation rate") was measured. Based on the measured value, the anti-sedimentation property was evaluated using the following criteria.

[0270] (Evaluation Criteria)

[0271] A: Sedimentation rate is greater than or equal to 80%

[0272] B: Sedimentation rate is greater than or equal to 50% and less than 80%

[0273] C: Sedimentation rate is greater than or equal to 25% and less than 50%

[0274] D: Sedimentation rate is less than 25%

[0275] In addition, the thermal stability was evaluated according to the following criteria based on the difference between the evaluation of the anti-settling property when stored at 25°C and the evaluation of the anti-settling property when stored at 60°C.

[0276] (Evaluation Criteria)

[0277] A: The evaluation of anti-settling properties at 25°C and 60°C is the same

[0278] (All are judged as A, All are judged as B, All are judged as C)

[0279] B: There is a one-level difference in the evaluation of anti-settling properties at 25°C and 60°C

[0280] (A judgment and B judgment, B judgment and C judgment, C judgment and D judgment)

[0281] C: There is a difference of two levels in the evaluation of anti-settling properties at 25°C and 60°C

[0282] (A judgment and C judgment, B judgment and D judgment)

[0283] D: There are three levels of difference in the evaluation of anti-settling properties at 25°C and 60°C

[0284] (A judgment and D judgment)

[0285] D: Unable to determine

[0286] (The evaluation of the anti-settling property at 25°C and the anti-settling property at 60°C were both rated D)

[0287] <Evaluation of Anti-Sagging Property>

[0288] As shown in Table 20, 75.60 parts of the water-based coating composition (before mixing the curing agent) prepared as described above and 47.90 parts of the epoxy curing agent prepared as described above were mixed to prepare a water-based coating composition (water-based epoxy coating). After the main agent and the curing agent were mixed, the mixture was diluted with ion exchange water so that the viscosity measured by a B-type viscometer became 20P (25°C), and the anti-sagging property was measured by a tester. Based on the measured value, the anti-sagging property was evaluated using the following criteria.

[0289] (Evaluation Criteria)

[0290] A: The measured value is greater than or equal to 450μm

[0291] B: The measured value is greater than or equal to 400μm and less than 450μm

[0292] C: The measured value is greater than 300μm and less than 400μm

[0293] D: The measured value is less than or equal to 300μm (equivalent to blank)

[0294] (Test Example 3: Evaluation of the Aqueous Coating Composition Prepared Using Evaluation Formula 2)

[0295] In Test Example 3, the performance test of the viscosity modifier was conducted using the acrylic latex paint formulation (Evaluation Formulation 2) shown in Table 21 as an evaluation formulation.

[0296]

Table 21

[0297] Table 21: Evaluation Formulation 2 (Acrylic Latex Paint Formulation)

[0298]

[0299] a=0.6% by mass

[0300] (Active ingredient conversion)

[0301] As shown in Table 21, 586.58 parts of NeoCryl XK-12 (manufactured by DSM) as an acrylic resin, 27.38 parts of dipropylene glycol monomethyl ether and 23.48 parts of dipropylene glycol monobutyl ether as a film-forming aid, and 98.70 parts of ion exchange water as a diluent were stirred and mixed, and then the pH was adjusted to 8.3 using 1.50 parts of N,N'-dimethylethanolamine as a pH adjuster to prepare a clear coating. 13.88 parts of Iriodin (registered trademark) 504 Red (manufactured by Merck) as a metallic pigment and 0.6 mass % (based on the mass of the viscosity imparting component (X) as an active ingredient) of any of the viscosity adjusters in Preparation Examples S1 to S19, S71 to 83 and Comparative Preparation Examples H1 to H9 and H11 were added to the clear coating and the mixture was stirred and mixed using a laboratory disperser. The dispersion was performed at a rotation speed of 2000 rpm for 10 minutes to produce water-based coating compositions of Examples 1 to 19, 73 to 85 and Comparative Examples 6 to 15. In addition, since the water-based coating composition of Comparative Example 13 had sample separation, the following evaluation was not performed.

[0302] <Evaluation of Anti-settling Property and Thermal Stability>

[0303] The water-based coating composition (acrylic latex coating) prepared as described above was diluted with ion exchange water so that the viscosity measured with Ford Cup #4 was 27 seconds (25°C), and the diluted coating was transferred to a 50 mL glass bottle. After that, it was left to stand in a constant temperature bath at 25°C and 60°C for 7 days, and the percentage of the volume of the settled pigment (Iriodin) relative to the total volume of the coating was measured (hereinafter referred to as "sedimentation rate"). Based on the measured value, the anti-settling property was evaluated using the following criteria.

[0304] (Evaluation Criteria)

[0305] A: Sedimentation rate is greater than or equal to 80%

[0306] B: Sedimentation rate is greater than or equal to 50% and less than 80%

[0307] C: Sedimentation rate is greater than or equal to 25% and less than 50%

[0308] D: Sedimentation rate is less than 25%

[0309] D: The coating shows a drawing property

[0310] D: Paint gelation

[0311] In addition, the thermal stability was evaluated according to the following criteria based on the difference between the evaluation of the anti-settling property when stored at 25°C and the evaluation of the anti-settling property when stored at 60°C.

[0312] (Evaluation Criteria)

[0313] A: The evaluation of anti-settling properties at 25°C and 60°C is the same

[0314] (All are judged as A, All are judged as B, All are judged as C)

[0315] B: There is a one-level difference in the evaluation of anti-settling properties at 25°C and 60°C

[0316] (A judgment and B judgment, B judgment and C judgment, C judgment and D judgment)

[0317] C: There is a difference of two levels in the evaluation of anti-settling properties at 25°C and 60°C

[0318] (A judgment and C judgment, B judgment and D judgment)

[0319] D: There are three levels of difference in the evaluation of anti-settling properties at 25°C and 60°C

[0320] (A judgment and D judgment)

[0321] D: Unable to determine

[0322] (The evaluation of the anti-settling property at 25°C and the anti-settling property at 60°C were both rated D)

[0323] (Test Example 4: Evaluation of the Aqueous Coating Composition Prepared Using Evaluation Formula 3)

[0324] In Test Example 4, the performance test of the viscosity modifier was conducted using the acrylic melamine water-soluble paint formulation (Evaluation formulation 3) shown in Table 22 as an evaluation formulation.

[0325]

Table 22

[0326] Table 22: Evaluation formula 3 (acrylic melamine water-soluble coating formula)

[0327]

[0328] a=0.4% by mass

[0329] (Active ingredient conversion)

[0330] As shown in Table 22, 250.16 parts of WATERSOL S-727 (manufactured by DIC Corporation) as an acrylic resin, 35.87 parts of Cymel 303 (manufactured by Allnex Corporation) and 23.79 parts of WATERSOL S-695 (manufactured by DIC Corporation) as a melamine resin, and 583.31 parts of ion exchange water as a diluent were stirred and mixed, and then the pH was adjusted to 9.1 using 4.30 parts of N,N'-dimethylethanolamine as a pH adjuster to prepare a clear coating. To the clear coating was added 17.57 parts of Iriodin (registered trademark) 504 Red (manufactured by Merck Corporation) as a metallic pigment and 0.4 mass % (based on the mass of the viscosity imparting component (X) as an active ingredient) of any of the viscosity adjusters in Preparation Examples S9, S24 to S51 and Comparative Preparation Examples H1 to H5 and H10, and the mixture was stirred and mixed using a laboratory disperser. The dispersion was performed at a rotation speed of 2000 rpm for 10 minutes to produce the water-based coating compositions of Examples 24 to 52 and Comparative Examples 16 to 21.

[0331] <Evaluation of Anti-settling Property and Thermal Stability>

[0332] The water-based coating composition (acrylic melamine water-soluble coating) prepared as described above was diluted with ion exchange water so that the viscosity measured by a B-type viscometer was 350 mPa·s (25°C), and the diluted coating was transferred to a 50 ml glass bottle. After that, the coating was left to stand in a constant temperature bath at 25°C and 60°C for 7 days, and the sedimentation rate of the pigment (Iriodin) was measured. Based on the measured value, the anti-settling property was evaluated using the following criteria.

[0333] (Evaluation Criteria)

[0334] A: Sedimentation rate is greater than or equal to 80%

[0335] B: Sedimentation rate is greater than or equal to 50% and less than 80%

[0336] C: Sedimentation rate is greater than or equal to 25% and less than 50%

[0337] D: Sedimentation rate is less than 25%

[0338] D: The coating shows a drawing property

[0339] In addition, the thermal stability was evaluated according to the following criteria based on the difference between the evaluation of the anti-settling property when stored at 25°C and the evaluation of the anti-settling property when stored at 60°C.

[0340] (Evaluation Criteria)

[0341] A: The evaluation of anti-settling properties at 25°C and 60°C is the same

[0342] (All are judged as A, All are judged as B, All are judged as C)

[0343] B: There is a one-level difference in the evaluation of anti-settling properties at 25°C and 60°C

[0344] (A judgment and B judgment, B judgment and C judgment, C judgment and D judgment)

[0345] C: There is a difference of two levels in the evaluation of anti-settling properties at 25°C and 60°C

[0346] (A judgment and C judgment, B judgment and D judgment)

[0347] D: There are three levels of difference in the evaluation of anti-settling properties at 25°C and 60°C

[0348] (A judgment and D judgment)

[0349] D: Unable to judge (the evaluation of anti-settling property at 25°C and anti-settling property at 60°C was both judged as D)

[0350] [Evaluation results of water-based coating compositions]

[0351] The above Tables 12 to 18 show the types of viscosity modifiers used in the aqueous coating compositions of Examples 1 to 95 and Comparative Examples 1 to 21 manufactured as described above, the categories of evaluation formulations, and the evaluation results (anti-settling properties, thermal stability, coating stability over time, anti-sagging properties) related to these aqueous coating compositions.

[0352] As shown in Tables 12 to 16, the water-based coating compositions of Examples 1 to 95 all showed good (C or higher) anti-settling properties and thermal stability. In addition, the water-based coating compositions of Examples 20 to 23 and 53 to 72 all showed good (C or higher) coating stability over time and anti-sagging properties.

[0353] Here, from the comparison of Examples 1 to 8, the following can be found about the type of viscosity-imparting component (X). First, it can be seen that when the carbon number of the diamine component (A1) is large, there is a tendency that the anti-settling property is slightly reduced (especially, refer to Examples 1 and 3). Therefore, from the viewpoint of improving the anti-settling property, it is suggested that it is preferable to use a diamine having a carbon number of 10 or less as the diamine component (A1). Second, it can be seen that when only hydrogenated castor oil (A') is used as the viscosity-imparting component (X), there is a tendency that the thermal stability is slightly poor (especially, refer to Examples 1, 4 and 5). Therefore, from the viewpoint of improving the thermal stability, it is suggested that it is preferable to contain at least a diamide compound (A) as the viscosity-imparting component (X). Third, it can be seen that as long as at least a monocarboxylic acid (oxyacid) having a hydroxyl group is contained as the monocarboxylic acid component (A2), even if the raw material of the diamide compound (A) contains an aromatic diamine or an alkanoic acid having no hydroxyl group, etc., it still shows good (C judgment or above) anti-settling property and thermal stability. However, in this case, it is known that when the carbon number of the alkanoic acid is large (C18 or more), there is a tendency for the thermal stability to be slightly poor (especially, see Examples 7 and 8). Therefore, when the raw material of the diamide compound (A) contains an alkanoic acid, from the viewpoint of improving thermal stability, it is suggested that the carbon number is preferably 16 or less. In addition, from Comparative Examples 11 to 13, it is known that when the monocarboxylic acid having a hydroxyl group is not contained as the monocarboxylic acid component (A2), the anti-settling property and thermal stability are deteriorated.

[0354] Moreover, from the comparison of Examples 9 to 17 and Comparative Example 15, it can be seen that when the acid value of the polyamide compound (B) is 30 to 140, the anti-settling property and thermal stability are excellent.

[0355] Furthermore, from the comparison between Examples 9 and 18, it can be seen that when the viscosity modifier contains the polyamide compound (B), the anti-settling property and the thermal stability are excellent regardless of whether the neutralizing base (G) is an alcoholamine or an alkylamine.

[0356] In addition, from the comparison between Examples 9 and 19 and Comparative Example 9, it can be seen that when the total amount of the viscosity-imparting component (X) is 100 parts by mass, if the total content of the diamide compound (A) and the hydrogenated castor oil (A') is less than 60 parts by mass, the anti-settling property and thermal stability are deteriorated.

[0357] In addition, from the comparison of Examples 20 to 23, it can be seen that the content of the diamide compound (A) is preferably 3.0 mass % or more and 20.0 mass % or less, and more preferably 3.0 mass % or more and 15.0 mass % or less, from the viewpoint of improving anti-sagging properties.

[0358] In addition, according to the comparison of Examples 24 to 39, it can be seen that for the type of solvent (C), as long as the compound used as solvent (C) has at least one substituent among hydroxyl group, ether group, ester group, amide group and ketone group, it shows good (above C judgment) anti-sedimentation property and thermal stability.

[0359] In addition, according to the comparison between Examples 28 to 32 and Examples 40 to 44, when a specific solvent (e.g., BFDG, BFG, n-BuOH, BCS, BDG, etc.) is used as the solvent (C), the content of the solvent (C) can be greatly reduced (to less than half), that is, even if the amount of the solvent (C) is reduced, the same anti-sedimentation property and thermal stability can be obtained.

[0360] In addition, it can be seen from the comparison of Examples 31, 43, 45 to 52 that as long as the content of the first solvent (C) is 5% to 99% by mass, good (C judgment or above) anti-settling properties and thermal stability are shown. However, from the viewpoint of improving thermal stability, the content of the first solvent (C) is preferably 10% to 99% by mass.

[0361] In addition, from the comparison of Examples 53 to 67, it can be seen that, as for the type of surfactant (E), as long as it is a nonionic surfactant, good (C judgment or above) anti-settling property and thermal stability are shown. However, from the viewpoint of improving anti-sagging property, it is preferred to use a nonionic surfactant having an HLB value of 3 to 18.5 calculated by the Griffin method as the surfactant (E) (especially, refer to Example 63). Similarly, from the viewpoint of improving anti-sagging property, it is preferred to use a compound that does not contain an aromatic ring as the surfactant (E) (especially, refer to Example 56).

[0362] In addition, from Examples 68 to 72, the content of the surfactant (E) is preferably less than or equal to 300 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A'). Further, according to a comparison of these examples, from the viewpoint of improving the temporal stability and anti-sagging properties of the coating, the content of the surfactant (E) is more preferably less than or equal to 200 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A'). From the viewpoint of particularly improving the anti-sagging properties, the content of the surfactant (E) is more preferably greater than or equal to 40 parts by mass relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A').

[0363] In addition, according to the comparison of Examples 1 and 73 to 82, as long as the polarity of the second solvent (F) is relatively higher than that of the first solvent (C), regardless of the type of the second solvent (F), good anti-settling properties (above C judgment) and thermal stability are shown.

[0364] In addition, from Examples 1 and 83 to 85, the content of the second solvent (F) is preferably 20% by mass or less. Further, from the comparison of these Examples, it is known that from the viewpoint of improving thermal stability, the content of the second solvent (F) is more preferably 10% by mass or less. In addition, from the viewpoint of improving anti-settling properties, it is known that the content of the second solvent (F) is more preferably 10% by mass or less, and further preferably 5% by mass or less.

[0365] In addition, from the comparison between Example 21 and Example 86, the comparison between Example 53 and Example 87, the comparison between Example 54 and Example 88, the comparison between Example 59 and Example 89, the comparison between Example 64 and Example 90, the comparison between Example 65 and Example 91, the comparison between Example 67 and Example 92, the comparison between Example 43 and Example 93, the comparison between Example 71 and Example 94, and the comparison between Example 72 and Example 95, it can be seen that not only when the viscosity adjuster is added to the epoxy main component side (Evaluation Formula 1), but also when the viscosity adjuster is added to the amine main component side (Evaluation Formula 1b), excellent anti-settling property, thermal stability and anti-sagging property are obtained by adding the viscosity adjuster of the examples of the present invention.

[0366] On the other hand, as shown in Comparative Examples 1, 6, and 16 in Table 17, it can be seen that when a polyurethane thickener is used as a viscosity modifier, for example, the anti-sagging property is poor in a water-based two-component epoxy coating, and the anti-settling property and thermal stability are poor in other types of coatings.

[0367] In addition, as shown in Comparative Examples 2 to 4, 7 to 9, and 17 to 19 in Table 17, it can be seen that when the main component of the viscosity-imparting component (X) is a polyamide compound (B) and a large amount of amine is used as a neutralizing base, the anti-settling property, thermal stability, temporal stability of the coating, and anti-sagging property are poor.

[0368] Here, as shown in Reference Examples 1 to 3 in Table 18, when a viscosity modifier is used on the amine main agent side as in the past, even when the main component of the viscosity-imparting component (X) is a polyamide compound (B) and a large amount of amine is used as a neutralizing base, good anti-settling properties, thermal stability, and anti-sagging properties are obtained. Thus, the viscosity modifier whose main component of the viscosity-imparting component (X) is a polyamide compound (B) and a large amount of amine is used as a neutralizing base has been limited to being added only to the amine main agent side. However, the viscosity modifier of the present invention does not have such a limitation. That is, according to the present invention, not only when the viscosity modifier is added to the amine main agent side, but also when it is added to the epoxy main agent side, a viscosity adjustment having excellent anti-settling properties and thermal stability and being able to impart excellent temporal stability and anti-sagging properties to the water-based coating can be obtained.

[0369] In addition, as shown in Comparative Examples 5, 10, and 20 in Table 17, it can be seen that when a non-aqueous non-polar solvent is used as a solvent for the viscosity-imparting component (X), poor dispersion occurs in the aqueous coating composition, and thus the anti-settling property and thermal stability in the aqueous coating are poor.

[0370] Moreover, as shown in Comparative Example 21 in Table 17, it can be seen that when the first solvent (C) is not contained, the anti-settling property and the thermal stability are inferior.

Claims

1. A viscosity modifier for water-based resin, characterized in that: contain: 1% to 30% by mass of a viscosity-imparting component (X), wherein the viscosity-imparting component (X) is composed of a diamide compound (A) and / or hydrogenated castor oil (A'), wherein the diamide compound (A) is obtained by reacting a diamine component (A1) selected from the group consisting of diamines having 2 to 12 carbon atoms and a monocarboxylic acid component (A2) selected from the group consisting of monocarboxylic acids having at least a hydroxyl group; and 10% to 99% by mass of a first solvent (C), wherein the first solvent (C) has at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, an amide group, and a ketone group, The diamine component (A1) contains a linear or branched diamine. When the total amount of the viscosity-imparting component (X) is 100 parts by mass, the total amount of the diamide compound (A) and the hydrogenated castor oil (A′) is 100 parts by mass.

2. The viscosity modifier for aqueous resin according to claim 1, characterized in that The first solvent (C) has an HLB value of 3 to 10 as calculated by the Davis method.

3. The viscosity modifier for aqueous resin according to claim 1, characterized in that The first solvent (C) is at least one solvent selected from the group consisting of alcohol solvents, glycol ether solvents, di(glycol) ether solvents, tri(glycol) ether solvents, ester solvents and amide solvents, wherein the glycol ether solvents are ether solvents of the ether corresponding to the monomer of the glycol, the di(glycol) ether solvents are ether solvents of the ether corresponding to the dimer formed by dehydration condensation of two molecules of glycol, and the tri(glycol) ether solvents are ether solvents of the ether corresponding to the trimer formed by dehydration condensation of three molecules of glycol.

4. The viscosity modifier for aqueous resin according to claim 1, characterized in that It further contains a nonionic surfactant (E) having an HLB value of 3 to 18.5 as calculated by the Griffin method, The content of the surfactant (E) is 300 parts by mass or less relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A').

5. The viscosity modifier for aqueous resin according to claim 1, characterized in that further comprising a second solvent (F) having a relatively higher polarity than the first solvent (C), The content of the second solvent (F) is 20 mass % or less.

6. The viscosity modifier for aqueous resin according to claim 1, characterized in that further comprising water (D), The content of water (D) is 80 mass % or less.

7. A water-based coating composition comprising a water-based resin, a pigment and a viscosity modifier for the water-based resin, characterized in that: The aqueous resin viscosity modifier contains: 1% to 30% by mass of a viscosity-imparting component (X), wherein the viscosity-imparting component (X) is composed of a diamide compound (A) and / or hydrogenated castor oil (A'), wherein the diamide compound (A) is obtained by reacting a diamine component (A1) selected from the group consisting of diamines having 2 to 12 carbon atoms and a monocarboxylic acid component (A2) selected from the group consisting of monocarboxylic acids having at least a hydroxyl group; and 10 to 99% by mass of a first solvent (C), wherein the first solvent (C) has at least one substituent selected from the group consisting of a hydroxyl group, an ether group, an ester group, an amide group, and a ketone group, The diamine component (A1) contains a linear or branched diamine. When the total amount of the viscosity-imparting component (X) is 100 parts by mass, the total amount of the diamide compound (A) and the hydrogenated castor oil (A′) is 100 parts by mass.

8. The water-based coating composition according to claim 7, characterized in that: The first solvent (C) has an HLB value of 3 to 10 as calculated by the Davis method.

9. The aqueous coating composition according to claim 7, characterized in that: The first solvent (C) is at least one solvent selected from the group consisting of alcohol solvents, glycol ether solvents, di(glycol) ether solvents, tri(glycol) ether solvents, ester solvents and amide solvents, wherein the glycol ether solvents are ether solvents of the ether corresponding to the monomer of the glycol, the di(glycol) ether solvents are ether solvents of the ether corresponding to the dimer formed by dehydration condensation of two molecules of glycol, and the tri(glycol) ether solvents are ether solvents of the ether corresponding to the trimer formed by dehydration condensation of three molecules of glycol.

10. The water-based coating composition according to claim 7, characterized in that: It further contains a nonionic surfactant (E) having an HLB value of 3 to 18.5 as calculated by the Griffin method, The content of the surfactant (E) is 300 parts by mass or less relative to 100 parts by mass of the diamide compound (A) and / or hydrogenated castor oil (A').

11. The water-based coating composition according to claim 7, characterized in that: further comprising a second solvent (F) having a relatively higher polarity than the first solvent (C), The content of the second solvent (F) is 20 mass % or less.

12. The water-based coating composition according to claim 7, characterized in that: further comprising water (D), The content of water (D) is 80 mass % or less.

13. The water-based coating composition according to claim 7, characterized in that: The viscosity modifier for aqueous resin is contained in an amount of 0.1% by mass to 1.0% by mass of the viscosity-imparting component (X) relative to the total solid content of the aqueous coating composition.

Images