JP2008247977A - Anionic electrodeposition coating material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an anionic electrodeposition coating material comprising an aqueous polyolefin resin dispersion free from a nonvolatile adjuvant for making water-soluble or -dispersible and a charge control agent and being capable of forming a flexible transparent film excellent in durability, water resistance, and solvent resistance. <P>SOLUTION: The anionic electrodeposition coating material is one comprising the following polyolefin resin, wherein the polyolefin resin has a number-average particle diameter of 1 μm or smaller, and the aqueous dispersion is substantially free from a nonvolatile adjuvant for making water-soluble or -dispersible and a charge control adjuvant. The above polyolefin resin is a copolymer made from (A1) an unsaturated carboxylic acid or an anhydride thereof, (A2) an ethylenic hydrocarbon, and (A3) at least one compound selected from among an alkyl (meth)acrylate, an alkyl diacrylate, and (meth)acrylamide. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

    The present invention relates to an anionic electrodeposition paint comprising an aqueous dispersion mainly composed of an olefin resin.

    In the present invention, a stable aqueous dispersion can be obtained without the addition of a non-volatile aqueous additive, and anodic electrodeposition can be performed without the addition of a charge control aid. Since the electrodeposition coating composition of the present invention does not contain the above-described aqueous-forming auxiliary or charge-adjusting auxiliary, other polymer aqueous dispersions, metal ions, inorganic particles, or additives such as a crosslinking agent It has excellent mixing stability and has a high degree of freedom in designing as a paint. Furthermore, the polyolefin electrodeposition coating material of the present invention has the original properties of the polyolefin resin as they are, and can form a flexible transparent film excellent in water resistance. The film can be easily formed at a low temperature, and an excellent film can be obtained without curing, thereby contributing to energy saving.

    Aluminum is actively used as a building material and electrical material because it is lightweight and easy to process. However, since its corrosion resistance is poor, it is generally treated with an anionic electrodeposition paint after the surface is roughened by anodization. It is covered. The anionic electrodeposition coating is a so-called aqueous dispersion (emulsion) in which fine resin particles are dispersed in water, and is an aqueous solution in which an emulsification aid, a charge adjustment aid, a curing agent, a pigment, and the like are mixed. Conventionally, acrylic resins and amino resins have been mainly used as anionic paints for aluminum. Since these are fragile coatings as they are electrodeposited, they are cured by baking at 180 ° C. or higher after coating, but baking at such a high temperature causes cracks in the anodized film, There were problems such as generation of decomposition gas such as aldehyde from the curing agent.

  Compared to these conventional electrodeposition paints, if an aqueous coating film having higher water resistance and a toughness without being cured can be obtained, an excellent anion electrodeposition paint for aluminum can be provided. A high molecular weight olefin resin is promising as a candidate material because of its good water resistance and flexibility. However, it has been difficult to obtain an aqueous dispersion that is strongly hydrophobic and serves as a base for an electrodeposition coating. Therefore, until now, it has hardly been put to practical use.

    As for blends of olefin compounds and other resins, there have been actual examples and technical disclosures. For example, it is generally known that an aqueous dispersion of a resin containing a small amount of an olefin compound can be obtained by emulsion polymerization or suspension polymerization in the presence of an emulsifier or a compound having a protective colloid effect. However, as the olefin content in the resin increases, it becomes increasingly difficult to obtain a stable aqueous dispersion due to the influence of an increase in the reaction pressure during polymerization. Resins having a high olefin content are generally obtained by high-pressure radical polymerization in an ethylene plant or the like, and are usually not obtained in the state of an aqueous dispersion.

    On the other hand, it has been known for some time that an aqueous dispersion can be obtained even if a resin having a high olefin content is copolymerized with a large amount of unsaturated carboxylic acid components. For example, aqueous dispersions of ethylene-unsaturated carboxylic acid copolymer resins such as ethylene-acrylic acid copolymer resins and ethylene-methacrylic acid copolymer resins having an unsaturated carboxylic acid content of about 20% by mass have been known. ing.

    As a method for aqueous dispersion of a polyolefin resin containing an unsaturated carboxylic acid, the resin is dissolved in an organic solvent, or melted and liquefied, and mechanically dispersed in an aqueous medium. . For example, (Patent Document 1) and (Patent Document 2) describe an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer resin having an unsaturated carboxylic acid content of 5 to 30% by mass and a method for producing the same. Yes. However, only those having a very high content of unsaturated carboxylic acid of 15% by mass or more are exemplified in these, and the content of unsaturated carboxylic acid is less than 10% by mass, and further less than 5% by mass When an ethylene-unsaturated carboxylic acid copolymer is dispersed in an aqueous medium, the addition of a non-volatile aqueous additive is essential, and it is very difficult to obtain an aqueous dispersion without these additions. It was. Since carboxylic acid is a hydrophilic group and impairs the hydrophobicity of the resin, it has an effect that is contrary to water resistance. Therefore, the polyolefin resin containing many carboxylic acids was only inferior in water resistance.

    Nonvolatile aqueous auxiliary agents effective for aqueous dispersion of polyolefin resins with low carboxylic acid are known, such as alkali metal compounds, surfactants, low molecular weight carboxylic acid waxes, and water-soluble resins. . For example, (Patent Document 3) describes a method of dispersing a polyolefin resin in water by adding a carboxyl group-containing polyolefin wax as an aqueous additive. In addition, in (Patent Document 4), (Patent Document 5), (Patent Document 6), and (Patent Document 7), a polyolefin resin is obtained by using various emulsifiers and compounds having a protective colloid action as an aqueous agent. A method of dispersing in water is described. However, the addition of such a low molecular weight component is not preferable from the viewpoint of environment and hygiene because the mechanical performance inherent in the resin is impaired and there is a risk of bleeding out little by little after production. Further, a highly hydrophilic emulsifier and a compound having a protective colloidal action have a serious problem that they remain in the film even after drying and the water resistance of the film is significantly reduced.

On the other hand, the electrodeposition coating is applied to a metal substrate as an electrode by applying a direct current as in the electroplating method. In particular, those electrodeposited on the anode are called anion electrodeposition. In the anion electrodeposition coating, resin particles dispersed in water are electrophoresed on a positive potential anode and deposited on the electrode. Therefore, the resin needs to be negatively charged, and the charge amount is controlled by the amount of functional groups such as carboxylic acid groups and sulfonic acid groups in the resin, and a surfactant added as a charge adjusting aid. However, when the number of hydrophilic functional groups increases, the water resistance deteriorates as described above, and the addition of a surfactant has the same adverse effect. Therefore, these are preferably avoided as much as possible, but have not been realized so far.
JP 2000-72879 A JP 2000-119398 A Japanese Patent Publication No.58-42207 Japanese Patent Laid-Open No. Sho 62-252478 JP-A-5-163420 JP-A-7-82423 JP-A-9-296081

    In order to solve the above-mentioned problems, the present inventors have substantially not added a non-volatile aqueous additive or a charge adjusting auxiliary, so that the durability and water resistance of the polyolefin resin are not impaired. Another object of the present invention is to provide an anionic electrodeposition coating material comprising a polyolefin resin aqueous dispersion capable of forming a flexible transparent film excellent in solvent resistance.

    As a result of diligent efforts to solve the above problems, the inventors of the present invention dispersed a polyolefin resin having a specific unsaturated carboxylic acid content in an aqueous dispersion without adding a non-volatile aqueous additive or a charge adjusting auxiliary. Furthermore, the inventors have found a condition that they can be electrodeposited on an aluminum substrate efficiently, and have reached the anion electrodeposition coating material of the present invention.

An electrodeposition coating material comprising an aqueous dispersion containing the following polyolefin resin, wherein the polyolefin resin has a number average particle diameter of 1 μm or less, and a non-volatile aqueous auxiliary agent and a charge adjustment auxiliary agent are substantially contained in the aqueous dispersion. An anionic electrodeposition paint characterized by not containing it. Polyolefin resin: composed of (A1) an unsaturated carboxylic acid or an anhydride thereof, (A2) an ethylenic hydrocarbon, and (A3) at least one compound represented by any of the following formulas (I) to (IV) A polyolefin resin in which the mass ratio of each of the constituent components (A1) to (A3) satisfies the following formulas (1) and (2).
0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1)
(A2) / (A3) = 55 / 45-99 / 1 (2)

    The present invention is an anionic electrodeposition coating composed of an aqueous dispersion mainly composed of an olefin resin, and does not contain a non-volatile aqueous solubilization aid or charge control aid, so that other polymer aqueous dispersions, metals It has excellent mixing stability with additives such as ions, inorganic particles, or crosslinking agents, and has a high degree of freedom in designing as a paint. Furthermore, the polyolefin electrodeposition coating material of the present invention has the original properties of the polyolefin resin as they are, and can form a flexible transparent film excellent in water resistance and solvent resistance. The film can be easily formed at a low temperature, and an excellent film can be obtained without curing.

    Hereinafter, the present invention will be described in detail.

    The anionic electrodeposition coating material comprising the aqueous polyolefin resin dispersion in the present invention comprises an aqueous dispersion containing a specific polyolefin resin and an aqueous medium.

The polyolefin resin used in the present invention contains an unsaturated carboxylic acid or its anhydride (A1) component in an amount of 0.01% by mass or more and less than 5% by mass based on the entire resin [(A1) + (A2) + (A3)]. More preferably, the content should be 0.1% by mass or more and less than 5% by mass, more preferably 0.5% by mass or more and less than 5% by mass, and most preferably 1% by mass or more and 4% by mass or less. When the content of the component (A1) is less than 0.01% by mass, it becomes difficult to make the resin aqueous (liquefaction) and it is difficult to obtain a good aqueous dispersion. On the other hand, when the content of the unsaturated carboxylic acid or its anhydride is 5% by mass or more, it becomes easy to make it aqueous, but the mixing stability with other additives may be lowered.

    The unsaturated carboxylic acid or anhydride thereof that can be used as the component (A1) of the polyolefin resin is a compound having at least one carboxyl group or acid anhydride group in the molecule (in the monomer unit), specifically Examples thereof include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid, crotonic acid, and the like, as well as unsaturated dicarboxylic acid half esters and half amides. Of these, acrylic acid, methacrylic acid, maleic acid, and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable. Moreover, the unsaturated carboxylic acid should just be copolymerized in polyolefin resin, The form is not limited, For example, random copolymerization, block copolymerization, graft copolymerization etc. are mentioned.

    In the polyolefin resin used in the present invention, the component (A3) represented by any of the following formulas (I) to (IV) is necessary as a constituent component, and this component imparts hydrophilicity to the polyolefin resin. Even if the component (A1) is less than 5% by mass, it can be made aqueous without the addition of a non-volatile aqueous additive. The mass ratio (A2) / (A3) between the ethylene-based hydrocarbon (A2) component and the (A3) component must be in the range of 55/45 to 99/1, and 60/40 to 98/2. It is preferably 65/35 to 97/3, more preferably 70/30 to 97/3, and particularly preferably 75/25 to 97/3. When the ratio of the component (A3) to [(A2) + (A3)] is less than 1% by mass, it becomes difficult to make the polyolefin resin aqueous, and it is difficult to obtain a good aqueous dispersion. On the other hand, when the content ratio of the compound (A3) exceeds 45% by mass, the properties as the polyolefin resin by the component (A2) are lost, and the performance such as water resistance is deteriorated.

Examples of the ethylene hydrocarbon (A2) component constituting the polyolefin resin of the present invention include alkenes having 2 to 6 carbon atoms such as ethylene, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene, and the like. A mixture of these can also be used. Among these, alkenes having 2 to 4 carbon atoms such as ethylene, propylene, isobutylene and 1-butene are more preferable, and ethylene is particularly preferable.

    Examples of the component (A3) represented by any one of the above formulas (I) to (IV) constituting the polyolefin resin of the present invention include, for example, methyl (meth) acrylate represented by the formula (I), (meth) (Meth) acrylic acid esters such as ethyl acrylate and butyl (meth) acrylate, maleic acid esters such as dimethyl maleate, diethyl maleate and dibutyl maleate represented by formula (II), formula (III) (Meth) acrylic acid amides represented by formula (IV), alkyl vinyl ethers represented by formula (IV) such as methyl vinyl ether and ethyl vinyl ether, vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl versatate, etc. Vinyl alcohols obtained by saponifying vinyl esters with basic compounds, etc. These mixtures can also be used. Among these, (meth) acrylic acid esters represented by the formula (I) are more preferable, and methyl (meth) acrylate or ethyl (meth) acrylate is particularly preferable.

    The polyolefin resin used in the present invention is most preferably a terpolymer comprising ethylene, methyl acrylate or ethyl acrylate, and maleic anhydride. Here, the acrylic ester unit may be converted into an acrylic acid unit by hydrolyzing a small part of the ester bond when the resin is made into an aqueous solution described later. It suffices if the ratio of each constituent component taking into account the change is within a specified range.

    In addition, unsaturated carboxylic anhydride units such as maleic anhydride units constituting the polyolefin resin in the present invention form an acid anhydride structure in which the adjacent carboxyl group is dehydrated and cyclized in the dry state of the resin. In an aqueous medium containing a basic compound, a part or all of the ring is opened to facilitate the structure of a carboxylic acid or a salt thereof. In the present invention, when the amount is defined based on the amount of carboxyl group of the resin, the calculation is performed assuming that all acid anhydride groups in the resin are ring-opened to form carboxyl groups.

    The polyolefin resin used in the present invention may be copolymerized with a small amount of other monomers. Examples include dienes, (meth) acrylonitrile, vinyl halides, vinylidene halides, carbon monoxide, sulfur disulfide, and the like.

    The polyolefin resin used in the present invention has a melt flow rate of 190 to 500 g / 10 minutes, preferably 0.1 to 300 g / 10 minutes, more preferably 0.1 to 250 g / 10 minutes, at 190 ° C. and a load of 2160 g, which is a measure of molecular weight. More preferably 0.5 to 200 g / 10 min, most preferably 1 to 100 g / 10 min can be used. When the melt flow rate of the polyolefin resin is less than 0.01 g / 10 min, it becomes difficult to make the resin water-based and it is difficult to obtain a good aqueous dispersion. On the other hand, when the melt flow rate of the polyolefin resin exceeds 500 g / 10 min, the coating obtained from the aqueous dispersion becomes hard and brittle, and the mechanical strength decreases.

    The method for synthesizing the polyolefin resin used in the present invention is not particularly limited, but it is preferable not to use an emulsifier or a protective colloid in view of the gist of the present invention. Generally, it is obtained by high-pressure radical copolymerization of a monomer constituting the polyolefin resin in the presence of a radical generator. In addition, the unsaturated carboxylic acid or its anhydride may be graft copolymerized (grafted modification).

    In the aqueous dispersion of the present invention, the above polyolefin resin is dispersed or dissolved in an aqueous medium. Here, the aqueous medium is a medium composed of a liquid containing water as a main component, and may contain a water-soluble organic solvent described later. Moreover, the basic compound mentioned later may be contained.

    Further, the number average particle diameter (hereinafter referred to as mn) of the polyolefin resin particles dispersed in the aqueous dispersion of the present invention needs to be 1 μm or less from the viewpoint of improving the storage stability of the aqueous dispersion. From the viewpoint of the smoothness and low-temperature film-forming property of the electrodeposition coating film, it is preferably 0.5 μm or less, more preferably 0.3 μm or less, further preferably 0.2 μm or less, and most preferably less than 0.1 μm. Further, the weight average particle size (hereinafter, mw) is also preferably 1 μm or less, more preferably 0.5 μm or less, further preferably 0.3 μm or less, and most preferably 0.2 μm or less. The degree of particle dispersion (mw / mn) is preferably 1 to 3, more preferably 1 to 2.5, and preferably 1 to 2 from the viewpoint of the storage stability of the aqueous dispersion, the smoothness of the coating film, and the low-temperature film-forming property. Particularly preferred.

    The resin content in the aqueous dispersion of the present invention can be appropriately selected depending on the film forming conditions, the desired thickness and performance of the resin film, and is not particularly limited. However, the viscosity of the coating composition is kept at an appropriate level. And 1-60 mass% is preferable at the point which expresses favorable film formation ability, 3-55 mass% is more preferable, 5-50 mass% is further more preferable, 10-45 mass% is especially preferable.

    The aqueous dispersion of the present invention is characterized in that it contains substantially no non-volatile aqueous solubilizing aid, and the polyolefin resin can be stably maintained in an aqueous medium with a number average particle diameter of 1 μm or less without using these. Can do. The non-volatile water-based auxiliary agent remains in the polyolefin resin even after the film is formed, and plasticizes the film, thereby deteriorating the properties of the polyolefin resin, such as water resistance. Since the present invention does not substantially contain a non-volatile water-immobilizing aid, it has excellent coating properties, particularly water resistance. Here, the “aqueous auxiliary” means a drug or compound added for the purpose of promoting aqueous formation or stabilizing the aqueous dispersion in the production of an aqueous dispersion, and “nonvolatile” means It means that it does not have a boiling point at normal pressure or has a high boiling point (for example, 300 ° C. or higher) at normal pressure. “Substantially no non-volatile aqueous solubilizing aid” means that no non-volatile aqueous solubilizing aid is actively added to the system, resulting in the absence of these. It is particularly preferable that the content of such a nonvolatile aqueous auxiliary agent is zero, but it may be contained in an amount of less than 0.1% by mass with respect to the polyolefin resin component as long as the effects of the present invention are not impaired.

    Examples of the non-volatile auxiliary agent used in the present invention include an emulsifier described later, a compound having a protective colloid action, a modified wax, an acid-modified compound having a high acid value, and a water-soluble polymer. Examples of the emulsifier include a cationic emulsifier, an anionic emulsifier, a nonionic emulsifier, and an amphoteric emulsifier. In addition to those generally used for emulsion polymerization, surfactants are also included. For example, anionic emulsifiers include higher alcohol sulfates, higher alkyl sulfonates, higher carboxylates, alkyl benzene sulfonates, polyoxyethylene alkyl sulfate salts, polyoxyethylene alkyl phenyl ether sulfate salts, vinyl sulfosuccinates. Nonionic emulsifiers include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyethylene glycol fatty acid ester, ethylene oxide propylene oxide block copolymer, polyoxyethylene fatty acid amide, ethylene oxide-propylene oxide. Compounds having a polyoxyethylene structure such as copolymers and sorbitan derivatives such as polyoxyethylene sorbitan fatty acid esters And examples of the amphoteric emulsifiers, lauryl betaine, lauryl dimethyl amine oxide, and the like.

    Compounds having protective colloid action, modified waxes, acid-modified compounds with high acid values, water-soluble polymers include polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, modified starch, polyvinyl pyrrolidone Polyacrylic acid and salts thereof, carboxyl group-containing polyethylene wax, carboxyl group-containing polypropylene wax, carboxyl group-containing polyethylene-propylene wax, etc., and acid-modified polyolefin waxes having a number average molecular weight of usually 5000 or less and salts thereof, acrylic acid- Maleic anhydride copolymer and its salt, styrene- (meth) acrylic acid copolymer, ethylene- (meth) acrylic acid copolymer, isobutylene-maleic anhydride alternating Polymers, carboxyl group-containing polymers having an unsaturated carboxylic acid content of 10% by mass or more, such as (meth) acrylic acid- (meth) acrylic acid ester copolymers, and salts thereof, polyitaconic acid and salts thereof, and amino groups Examples thereof include water-soluble acrylic copolymers, gelatin, gum arabic, and casein, which are generally used as fine particle dispersion stabilizers.

    In the aqueous dispersion of the present invention, the carboxyl group in the polyolefin resin is preferably neutralized with a basic compound. Aggregation between the fine particles is prevented by the electric repulsive force between the carboxyl anions generated by neutralization, and stability is imparted to the aqueous dispersion. The basic compound used in making the aqueous solution may be any compound that can neutralize the carboxyl group. Therefore, the basic compound added for such a purpose can be said to be an aqueous additive, but a volatile basic compound is used in order not to impair the effects of the present invention.

    As such a basic compound, ammonia or an organic amine compound that volatilizes at the time of film formation is preferable from the viewpoint of water resistance of the film, and an organic amine compound having a boiling point of 30 to 250 ° C., more preferably 50 to 200 ° C. is particularly preferable. When the boiling point is less than 30 ° C., the rate of volatilization at the time of making the resin aqueous later described increases, and the aqueous formation may not proceed completely. When the boiling point exceeds 250 ° C., it becomes difficult to disperse the organic amine compound from the resin film by drying, and the water resistance of the film may deteriorate.

    Specific examples of the organic amine compound include triethylamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine, diethylamine, and 3-ethoxypropylamine. , 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, 3-methoxypropylamine, monoethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like. The addition amount of the basic compound is preferably 0.5 to 3.0 times equivalent, more preferably 0.8 to 2.5 times equivalent, and particularly preferably 1.01 to 2.0 times equivalent to the carboxyl group in the polyolefin resin. If the amount is less than 0.5 times equivalent, the effect of adding a basic compound is not recognized. If the amount exceeds 3.0 times equivalent, the drying time during film formation may be prolonged, or the aqueous dispersion may be colored.

    In the present invention, it is preferable to add an organic solvent at the time of aqueous formation in order to promote aqueousization of the polyolefin resin and reduce the dispersed particle size. The amount of the organic solvent to be used is preferably 40% by mass or less in the aqueous medium, more preferably 1 to 40% by mass, further preferably 2 to 35% by mass, and particularly preferably 3 to 30% by mass. When the amount of the organic solvent exceeds 40% by mass, it cannot be regarded as an aqueous medium substantially and does not deviate from one of the objects of the present invention (environmental protection). Stability may be reduced.

    In general, a part of the organic solvent contained in the aqueous dispersion can be distilled out of the system by a solvent removal operation called stripping. The amount of the organic solvent in the dispersion may be appropriately reduced within the above range, and may be 10% by mass or less, and 3% by mass or less is preferable from an environmental viewpoint. In order to distill off the organic solvent by stripping, it is necessary to take measures in the production process such as increasing the pressure reduction of the equipment or extending the operation time, so the lower limit of the amount of organic solvent considering such productivity is 0.01. It is about mass% (the detection limit of the analytical instrument used for the measurement of the present invention). However, even if it is less than 0.01% by mass, the performance as an aqueous dispersion is not particularly problematic. Even if the amount of the organic solvent is reduced by stripping, the aqueous dispersion of the present invention is not particularly affected in terms of performance and can be used favorably for various applications.

    Examples of the stripping method include a method in which the aqueous dispersion is heated with stirring at normal pressure or reduced pressure to distill off the organic solvent. The organic solvent content can be quantified by gas chromatography. Further, since the solid content concentration is increased by distilling off the aqueous medium, for example, in the case where the viscosity increases and the workability deteriorates, water is added to the aqueous dispersion in advance. You can also.

    As an organic solvent, in order to obtain a good aqueous dispersion, one or more atoms (specifically, oxygen, nitrogen, fluorine, chlorine) having Pauling electronegativity of 3.0 or more are contained in the molecule. It is preferable to use what is doing. Among them, those having a solubility in water at 20 ° C. of 5 g / L or more are preferably used, and more preferably 10 g / L or more.

    Specific examples of the organic solvent used in the present invention include methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, tert-butanol, n-amyl alcohol, isoamyl alcohol, sec-amyl. Alcohols such as alcohol, tert-amyl alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol and cyclohexanol, ketones such as methyl ethyl ketone, methyl isobutyl ketone, ethyl butyl ketone, cyclohexanone and isophorone , Ethers such as tetrahydrofuran, dioxane, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, acetic acid-3-meth Cibutyl, methyl propionate, ethyl propionate, diethyl carbonate, dimethyl carbonate, etc., ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol ethyl ether acetate , Glycol derivatives such as diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol ethyl ether acetate, propylene glycol, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol methyl ether acetate Furthermore, 3-methoxy-3-methylbutanol, 3-methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate, and the like are preferable. Among them, those having a boiling point of 30 to 250 ° C. are preferable. Those with ˜200 ° C. are particularly preferred. These organic solvents may be used in combination of two or more. In addition, when the boiling point of the organic solvent is less than 30 ° C., the ratio of volatilization when the resin is made aqueous increases, and the efficiency of aqueous formation may not be sufficiently increased. An organic solvent having a boiling point exceeding 250 ° C. is difficult to be scattered from the resin film by drying, and the water resistance of the film may be deteriorated.

    Among the above organic solvents, ethanol, n-propanol, isopropanol, n-butanol, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, and the like are highly effective in promoting the aqueous formation of the resin and easily remove the organic solvent from the aqueous medium. Dioxane, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether are preferable, and ethanol, n-propanol, and isopropanol are particularly preferable from the viewpoint of low temperature drying property.

    The anionic electrodeposition coating composition of the present invention is characterized in that it contains substantially no charge adjusting aid in the aqueous dispersion, and anionic electrodeposition can be performed only by the charge of the resin carboxylic acid without using them. That is, it is adjusted to be electrodeposited with a necessary and sufficient amount of carboxylic acid so as not to inhibit water resistance.

    Here, the “charge adjusting aid” is a drug or compound added for the purpose of imparting electric charge to the resin to enable electrodeposition, and an anionic surfactant or the like is generally used. . Examples of such anionic surfactants include higher alcohol sulfates, higher alkyl sulfonates, higher carboxylates, alkyl benzene sulfonates, polyoxyethylene alkyl sulfate salts, and polyoxyethylene alkyl phenyl ether sulfates. Examples thereof include salts and vinyl sulfosuccinate. “Substantially free of charge control aids” means that no charge control aids are actively added to the system, resulting in no inclusion of these. Such a charge adjustment aid is particularly preferably zero in content, but may be contained in an amount of less than 0.1% by mass with respect to the polyolefin resin component as long as the effects of the present invention are not impaired.

    The aqueous polyolefin resin dispersion of the present invention is easily electrodeposited, and can form a highly transparent film without heat treatment after electrodeposition. Here, “haze (cloudiness value)” of a coat film coated with an aqueous polyolefin resin dispersion is used as a measure of film forming property and transparency. A film having a haze of 2.0 to 5.0 (%) is used as a substrate, and an aqueous polyolefin resin dispersion is electrodeposited so that the coat film thickness is 2 μm. The haze of the entire coated film thus obtained is 10.0 (%) or less in the present invention. The closer the haze of this coat film is to the haze of the base film, the higher the transparency. When the haze was 10.0 (%) or less, the transparency of the coat film was visually good, and at this time, the aqueous dispersion was judged to be capable of forming a transparent film. One of the features of the aqueous polyolefin resin dispersion of the present invention is that it is possible to produce a transparent film in an electrodeposited state without any heat treatment, but the melting point of the dispersed resin. Heat treatment at a lower temperature (more specifically, 25 ° C. or lower) has no problem, and is one preferred embodiment. Regarding heat treatment at a temperature higher than the melting point, by keeping the molecular weight of the aqueous polyolefin resin dispersion of the present invention relatively high, it is possible to suppress the flow of the membrane and to withstand high temperature heating. can get. It is suitable for shortening the drying time for removing moisture after electrodeposition.

    Next, the manufacturing method of the polyolefin resin aqueous dispersion is demonstrated. The method for obtaining the aqueous polyolefin resin dispersion of the present invention is not particularly limited. For example, each component described above, that is, a polyolefin resin having a specific composition, a basic compound, water, and an organic solvent as necessary, Preferably, a method of heating and stirring in a sealable container can be employed, and this method is most preferable. According to this method, a polyolefin resin having a specific composition can be satisfactorily made into an aqueous dispersion without substantially adding a non-volatile aqueous additive such as an emulsifier component or a compound having a protective colloid effect.

    Any container may be used as long as it is equipped with a tank into which a liquid can be charged and can appropriately stir the mixture of the aqueous medium and the resin powder or granular material charged into the tank. As such a device, a device widely known to those skilled in the art as a solid / liquid stirring device or an emulsifier can be used, and a device capable of pressurization of 0.1 MPa or more is preferably used. The agitation method and the rotation speed of the agitation in the present invention are not particularly limited. However, sufficient agitation is achieved even at a low agitation where the resin is in a floating state in an aqueous medium, and a high agitation (eg, 1000 rpm or more) is not essential Absent. For this reason, the aqueous dispersion can be produced with a simple apparatus.

    The shape of the polyolefin resin used for the aqueous treatment is not particularly limited, but it is preferable to use a granular or powdery particle having a particle diameter of 1 cm or less, preferably 0.8 cm or less from the viewpoint of increasing the aqueousization speed.

    An aqueous medium composed of water, a basic compound and an organic solvent, and a granular or powdery polyolefin resin are put into the tank of this apparatus, and they are preferably stirred and mixed at a temperature of 40 ° C. or lower. Next, the polyolefin resin is sufficiently made aqueous by maintaining stirring at a temperature of 80 to 200 ° C, preferably 90 to 200 ° C, more preferably 100 to 190 ° C, and preferably stirring for 5 to 120 minutes. And then cooling to 40 ° C. or lower, preferably with stirring, to obtain an aqueous dispersion. When the temperature in the tank is less than 80 ° C., it becomes difficult to make the polyolefin resin aqueous. When the temperature in the tank exceeds 200 ° C., the molecular weight of the polyolefin resin may decrease. As a heating method in the tank, heating from the outside of the tank is preferable. For example, the tank can be heated using oil or water, or a heater can be attached to the tank for heating. Examples of the cooling method in the tank include a method of naturally cooling at room temperature and a method of cooling using oil or water at 0 to 40 ° C.

    After this, jet pulverization may be further performed as necessary. The jet pulverization treatment here means that fluid such as aqueous polyolefin resin dispersion is ejected from pores such as nozzles and slits under high pressure, and resin particles or resin particles collide with a collision plate. Further, the resin particles are further refined by mechanical energy. Specific examples of the apparatus include APVGAULIN Homogenizer, Mizuho Kogyo Microfluidizer M-110E / H, and the like.

    Examples of a method for adjusting the solid content concentration of the aqueous dispersion thus obtained include a method in which the aqueous medium is distilled off or diluted with water so as to obtain a desired solid content concentration.

    As described above, the aqueous dispersion of the present invention is obtained by preparing a uniform liquid by dispersing or dissolving a polyolefin resin in an aqueous medium. Here, the uniform liquid state means that, in terms of appearance, a portion where the solid content concentration is locally different from other portions such as precipitation, phase separation or skinning is not found in the aqueous dispersion. Say.

    Further, the aqueous yield in the production of the aqueous dispersion can be known from the amount of coarse particles remaining in the obtained aqueous dispersion. Specifically, the aqueous dispersion is filtered under pressure (air pressure 0.2 MPa) through a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), and the amount of resin remaining on the filter is measured. Even when the amount of residual resin is large and the yield is low, if the above-mentioned filtration is performed during the production process to remove such coarse particles, it can be used as an aqueous dispersion in the subsequent steps. Although the aqueous yield in the present invention may be slightly reduced depending on the conditions, it is generally very good, and aqueous formation is achieved with almost no coarse particles remaining.

The aqueous polyolefin resin dispersion thus produced is excellent in low-temperature film-forming properties, and can form a transparent film even under drying conditions below the melting point of the resin.
Since the polyolefin resin aqueous dispersion of the present invention has a low content of unsaturated carboxylic acid, it is excellent in mixing stability with various additives. For example, an aqueous dispersion of another polymer, metal ions, inorganic particles, or a crosslinking agent can be added.

    The aqueous dispersion of other polymer is not particularly limited. For example, polyvinyl acetate, ethylene-vinyl acetate copolymer, polyvinyl chloride, polyvinylidene chloride, ethylene- (meth) acrylic acid copolymer, styrene-maleic acid resin, styrene-butadiene resin, butadiene resin, acrylonitrile-butadiene Examples include aqueous dispersions such as resins, poly (meth) acrylonitrile resins, (meth) acrylamide resins, chlorinated polyethylene resins, chlorinated polypropylene resins, polyester resins, modified nylon resins, urethane resins, phenol resins, silicone resins, and epoxy resins. be able to. You may use these in mixture of 2 or more types.

    Usually, in aqueous dispersions, when stability of fine particles is imparted by electrical repulsive force such as carboxyl anion, the addition of various metal ions causes the fine particles to aggregate and the stability of the dispersion to decrease. Is well known. On the other hand, the aqueous dispersion of the present invention is excellent in stability even when a metal ion is added, for example, for the purpose of imparting performance as a coating agent. The type of metal ion is selected according to the purpose and is not particularly limited. For example, lithium, sodium, calcium, barium, magnesium, zinc, copper, cobalt, aluminum, and the like can be used. You may use these in mixture of 2 or more types. Further, the addition amount is not particularly limited, and can be used in a wide range of addition amounts. However, when used as a coating agent, the metal ion is preferably 10 to 90 mol% with respect to the carboxyl group amount of the polyolefin resin, 20 to 80 mol% is more preferable.

    As inorganic particles, metal oxides such as magnesium oxide, zinc oxide and tin oxide, inorganic particles such as calcium carbonate and silica, and water-swellable layered inorganic compounds such as vermiculite, montmorillonite, hectorite and synthetic mica are added. be able to. The average particle diameter of these inorganic particles is preferably 0.005 to 10 μm, more preferably 0.005 to 5 μm from the viewpoint of the stability of the aqueous dispersion. Inorganic particles may be used as a mixture of two or more.

    In order to further improve various coating film performances such as water resistance, 0.01 to 100 parts by mass, preferably 0.1 to 60 parts by mass, of a crosslinking agent can be added to 100 parts by mass of the resin in the aqueous dispersion. When the addition amount of the crosslinking agent is less than 0.01 parts by mass, the degree of improvement in the coating film performance is small, and when it exceeds 100 parts by mass, the performance such as workability is deteriorated. As the crosslinking agent, a crosslinking agent having self-crosslinking property, a compound having a plurality of functional groups that react with a carboxyl group in the molecule, a metal complex having a polyvalent coordination site, etc. can be used. Of these, isocyanate compounds , Melamine compounds, urea compounds, epoxy compounds, carbodiimide compounds, oxazoline group-containing compounds, zirconium salt compounds, silane coupling agents and the like are preferable. Moreover, you may use combining these crosslinking agents.

    Furthermore, the aqueous dispersion of the present invention may be applied to various agents such as a leveling agent, an antifoaming agent, an anti-bacterial agent, a pigment dispersant, an ultraviolet absorber, a pigment such as titanium oxide, zinc white, and carbon black as necessary. The aqueous dispersion of the present invention can be used as a coating agent or a paint by adding a dye. It is also possible to add organic or inorganic compounds other than those described above to the aqueous dispersion as long as the stability of the aqueous dispersion is not impaired.

    Additives such as aqueous dispersions of other polymers shown above, metal ions, inorganic particles, crosslinking agents, leveling agents, antifoaming agents, anti-waxing agents, pigment dispersants, UV absorbers, pigments or dyes are 2 More than one type may be used in combination.

    The resin composition obtained from the aqueous dispersion of the present invention can be used as an adhesive because it has excellent adhesion to various substrates in addition to paint and coating applications. For example, it can be used for metal, glass, plastic moldings, films, papers, etc., and is suitable for purposes such as heat sealing.

Next, the usage method of the anion electrodeposition coating material of this invention is demonstrated.
The anion electrodeposition paint of the present invention is composed of an aqueous dispersion mainly composed of a polyolefin resin, and further mixed with other resins such as epoxy, urethane and ester, and adjusted in color tone such as a crosslinking agent, pigment and dye. You may add an agent etc. suitably. The paint is electrodeposited on the anode by energization, and the equipment can be used without particular limitation as long as it is for general anion electrodeposition coating. In the electrodeposition paint of the present invention, the base polyolefin resin already has a high molecular weight in the paint state and is excellent in low-temperature film-forming properties, so that a high-temperature baking process is not particularly necessary. However, in the present invention, there is no problem even if a crosslinking agent is added and baking is performed in the same manner as before. In the present invention, even if such a crosslinking treatment is performed, the crosslinking density does not become higher than that of a conventional thermosetting resin, so that a strong film can be obtained without embrittlement. Therefore, the cross-linking agent may be considered as one of the important design factors in the paint of the present invention.

  As the metal substrate to be electrodeposited, aluminum or titanium is particularly suitable, but iron, stainless steel, copper or the like can be similarly electrodeposited. However, in the case of these base metals, since the ratio of the metal eluting as ions is higher than in the base metal substrate used as the anode, it is easy to mix and color in the coating film, and it is necessary to be careful in applications where the color tone is severe. .

  The electrodeposition paint of the present invention is formed on the anode substrate by energization. Usually, the base material pulled up from the electrodeposition tank is dried by removing excess adhered paint by washing with water. The electrodeposition paint of the present invention is characterized in that a good film is formed while being electrodeposited, and drying is not performed for the purpose of film formation, but for removing water remaining in the film. In general, the amount of residual moisture is about 10% by mass, which is very small compared to the case where the coating method other than the electrodeposition method has to remove water several times that of the film. Therefore, the drying conditions can be greatly simplified. Further, as described above, since the film formation has already been completed, there is no dripping of the film until drying, so that the production method is easy and the yield is good.

    As a heating device at this time, a normal hot air circulation type oven, an infrared heater or the like may be used, and air drying may be used if it takes time in the process. Further, since the film is already formed in the electrodeposited state, the adhering moisture can be blown away by air blowing or rotational force, which is effective for shortening the drying time. The heating temperature and the heating time are appropriately selected depending on the characteristics of the metal base material to be anion-deposited, the type of curing agent described later, the blending amount, etc. Is preferably 30 to 250 ° C, more preferably 60 to 230 ° C, particularly preferably 80 to 210 ° C, and the heating time is preferably 1 second to 20 minutes, more preferably 5 seconds to 15 minutes, 5 seconds to 10 minutes is particularly preferred. In addition, when a crosslinking agent is added, in order to sufficiently advance the reaction between the carboxyl group in the polyolefin and the crosslinking agent, it is desirable to appropriately select the heating temperature and time depending on the type of the crosslinking agent.

    Further, in the anion electrodeposition paint of the present invention, the thickness of the resin film to be formed is appropriately selected depending on the application, but is preferably 0.01 to 100 μm, more preferably 0.1 to 50 μm, and more preferably 0.2 to 30 μm. Is particularly preferred. When the film is formed so that the thickness of the resin film falls within the above range, a resin film having excellent uniformity can be obtained. The thickness of the resin coating is not only selected as appropriate for the anion electrodeposition apparatus and its use conditions, but also the coating concentration, energization time, applied voltage, etc., suitable for the desired thickness of the resin coating. It is adjusted with. If electrodeposition is continued continuously, the concentration of the paint gradually decreases, so the concentration needs to be adjusted. The applied voltage is usually a constant voltage DC power supply, and generally 10 V or more and 100 V or less is appropriate. Further, it may be a constant current DC power supply or a pulse voltage power supply. Agitation of the paint during electrodeposition is effective for uniform film formation, and bubbling with an inert gas or application of ultrasonic waves is one of preferred means.

    The anion electrodeposition coating material of the present invention is excellent in solvent resistance because it is a resin having an olefin structure, and has flexibility because it can be made into a high molecular weight thermoplastic resin. Furthermore, since it is an aqueous dispersion that can be electrodeposited without using a non-volatile aqueous additive or charge control aid, it is excellent in water resistance. Thus, there has been no electrodeposition paint that satisfies each performance in a well-balanced manner, so that it can be suitably used for various coating and adhesive applications.

EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. Various characteristics were measured or evaluated by the following methods.
(1) Constitution of polyolefin resin It was determined by performing 1H-NMR analysis (manufactured by Varian, 300 MHz) at 120 ° C. in orthodichlorobenzene (d4).
(2) Residual amount of ester group after aqueousization After the aqueous polyolefin dispersion was dried at 150 ° C, 1H-NMR analysis at 120 ° C in orthodichlorobenzene (d4) (manufactured by Varian, 300 MHz), and the ester group residual rate (%) was determined with the ester group amount of the acrylate ester before being made water-based as 100.
(3) Solid content concentration of polyolefin resin aqueous dispersion An appropriate amount of the polyolefin dispersion was weighed and heated at 150 ° C. until the mass of the residue (solid content) reached a constant weight to determine the polyolefin resin solid content concentration.
(4) Viscosity of aqueous polyolefin resin dispersion The rotational viscosity of the aqueous dispersion at a temperature of 20 ° C was measured using a DVL-BII type digital viscometer (B type viscometer) manufactured by Tokimec.
(5) Average particle diameter of polyolefin resin particles The number average particle diameter and the weight average particle diameter were determined using a Microtrac particle size distribution analyzer UPA150 (MODEL No. 9340) manufactured by Nikkiso Co., Ltd.
(6) Aqueousization yield When the aqueous dispersion after water purification is pressure filtered (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), the mass of resin remaining on the filter is calculated. The yield was calculated from the charged resin mass.
(7) Appearance of aqueous dispersion The color of the aqueous dispersion was evaluated by visual observation.
(8) Electrodeposition test Place the aqueous dispersion into a 200 cc glass beaker and immerse two 100 mm long, 50 mm thick, 0.5 mm thick aluminum plates facing each other. Connected to the + and-poles of the -3030D. The aluminum plate was subjected to a 20 V constant voltage direct current for 2 minutes to conduct an electrodeposition test, and the adhered paint was washed and removed with running water, and then dried at 60 ° C. for 10 minutes with a hot air dryer LG-122 manufactured by Tabai Stec. The thickness of the film thus obtained was measured with a 3-dimensional shape measuring instrument DEKTAK3000 manufactured by ULVAC.
(9) Pot life The appearance when the aqueous polyolefin resin dispersion was allowed to stand at room temperature for 90 days was evaluated in the following three stages.
○: No change in appearance.
Δ: Thickening is observed.
X: Solidification, aggregation and precipitation are observed.
(10) Stability of mixing the aqueous polyolefin resin dispersion with other additives After mixing the aqueous polyolefin resin dispersion with other additives, and leaving it at room temperature, the appearance of the mixture (thickening, solidifying) , The number of days until the occurrence of aggregation and precipitation) changes.
(11) Content of organic solvent in aqueous polyolefin resin dispersion Gas chromatograph GC-8A manufactured by Shimadzu Corporation [using FID detector, carrier gas: nitrogen, column packing material (manufactured by GL Sciences): PEG-HT (5 %)-Uniport HP (60/80 mesh), column size: diameter 3 mm x 3 m, sample input temperature (injection temperature): 150 ° C, column temperature: 60 ° C, internal standard: n-butanol] A body or an aqueous dispersion diluted with water was directly put into the apparatus, and the content of the organic solvent was determined. The detection limit was 0.01% by mass.
(12) Melt flow rate (MFR) of polyolefin resin after water treatment
The aqueous polyolefin dispersion was taken in a glass petri dish and dried at 100 ° C. for 6 hours. The MFR of the obtained polyolefin resin was measured by the method described in JIS 6730 (190 ° C., 2160 g load).
Table 1 shows the composition of the resin used. In addition, melting | fusing point of resin described in Table 1 is a value measured by DSC (measuring device: DSC-7 manufactured by Perkin Elmer), and melt flow rate is a method described in JIS 6730 (190 ° C., 2160 g load) It is the value measured by.

Example 1
Using a stirrer equipped with a 1 L glass container that can be sealed with a heater, 60.0 g of polyolefin resin (A) (Bondyne HX-8210, manufactured by Sumitomo Chemical Co., Ltd.), 30.0 g of ethylene glycol-n-butyl ether , Bu-EG), 3.9 g (1.2 equivalents to the carboxyl group of maleic anhydride in the resin) of N, N-dimethylethanolamine (hereinafter DMEA) and 206.1 g of distilled water are charged into a glass container. When the stirring blade was rotated at a rotation speed of 300 rpm, the resin bottom was not observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 140 ° C. and further stirred for 20 minutes. Then, after putting it in a water bath and cooling to room temperature (about 25 ° C) while stirring at a rotational speed of 300 rpm, pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), A milky white uniform aqueous polyolefin resin dispersion E-1 was obtained. Various characteristics of the aqueous dispersion are shown in Table 2. The number average particle diameter and the weight average particle diameter were 0.060 μm and 0.088 μm, respectively, and the distribution was one peak, and the polyolefin resin was dispersed in a good state in the aqueous medium. Furthermore, the pot life of the aqueous dispersion was over 90 days. In addition, the ester group residual ratio of the resin after the aqueous treatment was 100%, and ethyl acrylate was not hydrolyzed. This ester group residual rate was 100% at room temperature for 90 days and remained unchanged after standing. Further, the MFR of the resin after being made aqueous was 200 g / 10 min, and there was no decrease in molecular weight. The haze of the coated film obtained by drying this aqueous dispersion in an atmosphere at 5 ° C. and 25 ° C. was 2.8%, and the transparency was good.
Example 2
An aqueous dispersion E-2 was obtained in the same manner as in Example 1 except that the amount of amine to be added was changed as shown in Table 2. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 3
An aqueous dispersion E-3 was obtained in the same manner as in Example 1 except that the type of amine to be added was triethylamine (hereinafter referred to as TEA). Various characteristics of the aqueous dispersion are shown in Table 2.
Example 4
The aqueous dispersion E was prepared in the same manner as in Example 1 except that the type of amine to be added was TEA, the type of organic solvent to be added was isopropanol (hereinafter referred to as IPA), and the addition amount was changed as shown in Table 2. -4 was obtained. Various characteristics of the aqueous dispersion are shown in Table 2. Incidentally, the ester group remaining rate of the resin after being made aqueous was 98%, and 2% of ethyl acrylate was hydrolyzed. This ester group residual ratio was 98% at room temperature for 90 days and remained unchanged after standing.
Example 5
The aqueous dispersion E was prepared in the same manner as in Example 1 except that the type of amine to be added was TEA, the type of organic solvent to be added was ethanol (hereinafter EtOH), and the addition amount was changed as shown in Table 2. Got -5. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 6
An aqueous dispersion E-6 was obtained in the same manner as in Example 1 except that the amount of Bu-EG to be added was changed as shown in Table 2. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 7
An aqueous dispersion E-7 was obtained in the same manner as in Example 1 except that ammonia (25% NH 3 water) was used as the type of basic compound to be added. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 8
An aqueous dispersion E-8 was obtained in the same manner as in Example 1 except that the solid content of the resin was 30% by mass. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 9
An aqueous dispersion E-9 was obtained in the same manner as in Example 1 except that the polyolefin resin (B) (Bondaine HX-8290, manufactured by Sumitomo Chemical Co., Ltd.) was used and the addition amount of amine was changed as shown in Table 2. It was. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 10
An aqueous dispersion was prepared in the same manner as in Example 1 except that the polyolefin resin (B) (Bondaine HX-8290, manufactured by Sumitomo Chemical Co., Ltd.) was used and the types and addition amounts of amine and organic solvent were changed as shown in Table 2. E-10 was obtained. Various characteristics of the aqueous dispersion are shown in Table 2.
Examples 11 and 12
An aqueous dispersion was prepared in the same manner as in Example 1 except that polyolefin resin (C) (Bondane TX-8030, manufactured by Sumitomo Chemical Co., Ltd.) was used and the types and addition amounts of amine and organic solvent were changed as shown in Table 2. E-11 and E-12 were obtained. Various characteristics of the aqueous dispersion are shown in Table 2.
Example 13
An aqueous dispersion was prepared in the same manner as in Example 1 except that polyolefin resin (D) (Bondaine LX-4110, manufactured by Sumitomo Chemical Co., Ltd.) was used and the types and addition amounts of amine and organic solvent were changed as shown in Table 2. E-13 was obtained. Various characteristics of the aqueous dispersion are shown in Table 2. In addition, the ester group residual ratio of the resin after being made aqueous was 95%, and 5% of ethyl acrylate was hydrolyzed. The ester group residual ratio was 95% at room temperature for 90 days and remained unchanged after standing.

Comparative Example 1
Except for using polyolefin resin (E) (Escor TR-5100, manufactured by Exxon Chemical Co., Ltd.), the same method as in Example 1 was performed, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. It was done. Therefore, the system temperature was raised to 160 ° C. and the mixture was stirred for 20 minutes, but the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave), but a large amount of resin was found on the filter. The resin could not be made water-based substantially.
Comparative Example 2
Poly (ethylene-maleic anhydride) (manufactured by Aldrich, 3 mass% maleic anhydride, viscosity at 140 ° C. is 1700-4500 cps) (F) as a polyolefin resin not containing compound (A3), amine and organic solvent The same method as in Example 1 was carried out except that the type and amount added were changed as shown in Table 3, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Therefore, the system temperature was raised to 160 ° C. and the mixture was stirred for 20 minutes, but the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave), but a large amount of resin was found on the filter. The resin could not be made water-based substantially.
Comparative Example 3
Using a stirrer equipped with a 1 L glass container that can be sealed with a heater, 60.0 g of polyolefin resin (A) (Bondyne HX-8210, manufactured by Sumitomo Chemical Co., Ltd.), 4.5 g (carboxyl of maleic anhydride in the resin) TEA of 1.2 times equivalent to the base), 6.0 g of polyoxyethylene polyoxypropylene glycol as an emulsifier, and 229.5 g of distilled water were charged in a glass container and stirred at a rotation speed of the stirring blade of 300 rpm. Precipitation of resin granules was not observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 180 ° C. and further stirred for 20 minutes. Then, after putting it in a water bath and cooling to room temperature (about 25 ° C) while stirring at a rotational speed of 300 rpm, we tried to apply pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave). However, clogging occurred. Accordingly, milky white aqueous polyolefin resin dispersion H-3 was obtained without filtration. Various characteristics of the aqueous dispersion are shown in Table 3.
Comparative Example 4
Except that the organic solvent was not added, the same method as in Example 1 was performed, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Therefore, the system temperature was raised to 160 ° C. and the mixture was stirred for 20 minutes, but the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave), but a large amount of resin was found on the filter. The resin could not be made water-based substantially.
Comparative Example 5
The same method as in Example 1 was used except that the polyolefin solvent (B) (Bondyne HX-8290, manufactured by Sumitomo Chemical Co., Ltd.) was used without adding an organic solvent, and the type and amount of amine to be added were changed as shown in Table 3. However, the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Therefore, the system temperature was raised to 160 ° C. and the mixture was stirred for 20 minutes, but the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave), but a large amount of resin was found on the filter. The resin could not be made water-based substantially.
Comparative Example 6
Except that no amine was added, the same method as in Example 1 was performed, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Therefore, the system temperature was raised to 160 ° C. and the mixture was stirred for 20 minutes, but the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (air pressure 0.2 MPa) was performed with a 300-mesh stainless steel filter (wire diameter 0.035 mm, plain weave), but a large amount of resin was found on the filter. The resin could not be made water-based substantially.

Example 14
The aqueous polyolefin resin dispersion E-1 obtained in Example 1 was mixed with an aqueous dispersion of another polymer. An aqueous polyurethane dispersion (Adekabon titer HUX-380, manufactured by Asahi Denka Kogyo Co., Ltd.) was used as the aqueous dispersion of the polymer. E-1 was stirred, and 50 parts by mass of the aqueous dispersion was added in terms of solid content to 100 parts by mass of solid content of E-1, and stirred at room temperature for 30 minutes (referred to as M-1). . Table 4 shows the mixing stability of the obtained liquid.
Examples 15-19
The aqueous polyolefin resin dispersion E-10 obtained in Example 10 and a crosslinking agent were mixed. As a crosslinking agent, a melamine compound (Cymel 327, manufactured by Mitsui Cytec Co., Ltd., Example 15), an epoxy compound (Denacol EX-313, manufactured by Nagase Kasei Kogyo Co., Ltd., Example 16, and Denacol EX-1310, manufactured by Nagase Kasei Kogyo Co., Ltd.) Example 17), an oxazoline group-containing compound (Epocross WS-700, manufactured by Nippon Shokubai Co., Ltd., Example 18), and a carbodiimide compound (Carbodilite E-02, manufactured by Nisshinbo Co., Ltd., Example 19) were used. E-10 was stirred, and the amount of the crosslinking agent shown in Table 4 in terms of solid content was added to 100 parts by mass of the solid content of E-10, followed by stirring at room temperature for 30 minutes. Table 4 shows the mixing stability of the obtained liquids (respectively referred to as M-2 to M-6).
Example 20
10 parts by mass of a layered inorganic compound (Kunipia F, manufactured by Kunimine Kogyo Co., Ltd.) and 250 parts by mass of glass beads are mixed with 100 parts by mass of the solid content of the polyolefin resin aqueous dispersion E-1 obtained in Example 1. After 1 hour of shaking dispersion with a paint shaker, the glass beads were removed. Table 4 shows the mixing stability of the obtained liquid (referred to as M-7).
Example 21
The same method as in Example 19 was performed except that magnesium oxide (particle diameter 0.01 μm, manufactured by Wako Pure Chemical Industries, Ltd.) was used instead of the layered inorganic compound. Table 4 shows the mixing stability of the obtained liquid (referred to as M-8).
Example 22
To the aqueous polyolefin resin dispersion E-1 obtained in Example 1, 30 mol% of sodium chloride with respect to the amount of carboxyl groups of the polyolefin resin was added and stirred at room temperature for 30 minutes. Table 4 shows the mixing stability of the obtained liquid (referred to as M-9).

Example 23
E-10 250 g and distilled water 85 g were charged into a 1 L 2-neck round bottom flask, a mechanical stirrer and a Liebig condenser were installed, and the flask was heated in an oil bath to distill off the aqueous medium. When about 90 g of the aqueous medium was distilled off, the heating was terminated and the mixture was cooled to room temperature. After cooling, the liquid component in the flask was pressure filtered (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), and the solid content concentration of the filtrate was measured to be 20.5% by mass. . While stirring the filtrate, distilled water was added to adjust the solid content concentration to 20.0% by mass. The content of the organic solvent (IPA) in this aqueous dispersion was 0.4% by mass. Further, when the appearance of this aqueous dispersion was visually observed, it was uniform with no precipitation or layer separation, and the number average particle diameter and weight average particle diameter were 0.070 μm and 0.092 μm, respectively. There was also one mountain. In addition, it was stable with no change in appearance even after standing at room temperature for 90 days. The haze of the coated film obtained by drying this aqueous dispersion in an atmosphere of 5 ° C. and 25 ° C. was 3.2% and 3.3%, respectively, and the transparency was good.
Example 24
E-11 250 g and distilled water 100 g were charged into a 1 L 2-neck round bottom flask, a mechanical stirrer and a Liebig condenser were installed, and the flask was heated in an oil bath to distill off the aqueous medium. When about 105 g of the aqueous medium was distilled off, heating was terminated and the mixture was cooled to room temperature. After cooling, the liquid component in the flask was pressure filtered (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), and the solid content concentration of the filtrate was measured to be 20.4% by mass. . While stirring the filtrate, distilled water was added to adjust the solid content concentration to 20.0% by mass. The content of the organic solvent (IPA) in this aqueous dispersion was 1.0% by mass. Further, when the appearance of this aqueous dispersion was visually observed, it was uniform with no precipitation or layer separation, and the number average particle diameter and weight average particle diameter were 0.094 μm and 0.148 μm, respectively. There was also one mountain. In addition, it was stable with no change in appearance even after standing at room temperature for 90 days. The haze of the coated film obtained by drying this aqueous dispersion in an atmosphere at 5 ° C. and 25 ° C. was 3.3%, and the transparency was good.
Comparative Examples 7-9
Using a stirrer equipped with a heat-resistant 1 L glass container with a heater, 60.0 g of ethylene-acrylic acid copolymer resin (Primacol 5980I, 20% acrylic acid copolymer by Dow Chemical) (G), 17.7 g (1.05 times equivalent to the carboxyl group of acrylic acid in the resin) of TEA and 222.3 g of distilled water were charged into a glass container and stirred at a rotation speed of 300 rpm. Precipitation of resin granules was not observed at the bottom of the container, and it was confirmed that the container was in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the system temperature was kept at 100 to 105 ° C. and further stirred for 20 minutes. Then, after putting it in a water bath and cooling to room temperature (about 25 ° C) while stirring at a rotational speed of 300 rpm, pressure filtration (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave), A slightly cloudy aqueous dispersion S-1 was obtained. At this time, almost no resin remained on the filter. Stirring S-1, and 100 mass parts of solid content of S-1, polyurethane aqueous dispersion (Adekabon titer HUX-380, manufactured by Asahi Denka Kogyo Co., Ltd., Comparative Example 7), and epoxy compound (Denacol) EX-313, manufactured by Nagase Kasei Kogyo Co., Ltd., Comparative Example 8) and Denacol EX-1310, manufactured by Nagase Kasei Kogyo Co., Ltd., Comparative Example 9) were added in the amounts shown in Table 4 in terms of solid content, and at room temperature for 30 minutes, Stir. Table 4 shows the mixing stability of the obtained liquid.
Table 5 shows the results of the adhesion test of each of the coating solutions -E-1, E-9, and M-1 to M-9.

Electrodeposition tests of Examples 1-5 and Comparative Example 10 The aqueous dispersions of Examples 1-5 were placed in a 200 cc glass beaker and immersed with two aluminum plates 100 mm long, 50 mm wide and 0.5 mm thick facing each other. The crocodile clips were connected to the positive and negative poles of a CUSTOM stabilized power supply cps-3030D. An electrodeposition test was conducted by applying a 20 V constant voltage direct current to the aluminum plate for 2 minutes, and the state of film formation was observed. The obtained sample was washed and removed of the adhering paint with running water, and then the adhering water was blown off with air, and the appearance was observed. In addition, a product dried at 60 ° C. for 10 minutes with a hot air dryer LG-122 manufactured by Tabeistec immediately after electrodeposition was also tested and compared with an air-dried sample. For comparison with these, an attempt was made to prepare the electrodeposition paints of Comparative Examples 1 to 3 comprising an olefin resin composition that was not the present invention, but a uniform aqueous dispersion could not be obtained. Was not served. As Comparative Example 10, an electrodeposition test was conducted in the same manner using an aqueous dispersion of Elitel KA-5034 (product of Unitika Co., Ltd.) made of a polyester resin as a sample that was not an olefin resin.

    The results are shown in Table 5. All of the aqueous dispersions of Examples 1 to 5 were formed on a positive electrode aluminum plate and exhibited good anion electrodeposition performance. The obtained coating was a film having good transparency after electrodeposition, and the transparency was maintained even when moisture was removed by air drying. The sample that had been dried at 60 ° C. for 10 minutes was no different from that by air drying, and was a good film with good uniformity.

    These electrodeposited aluminum plates were immersed in toluene, methyl ethyl ketone, and methanol for 1 hour, but no change was observed in the film, and it was confirmed that the solvent resistance was good.

In the polyester-based KA-5034 of Comparative Example 10, a transparent film could be electrodeposited on the aluminum substrate, but as the moisture was removed by air drying, the transparency was lost and a particulate deposit was formed. Similarly, the one that was heat-treated at 60 ° C. for 10 minutes after the electrodeposition was not transparent, but the one that was heat-treated at 150 ° C. for 20 seconds gave a transparent coating film. This coating film was immersed in toluene, methyl ethyl ketone, and methanol for 1 hour, but the film was dissolved and peeled with toluene and methyl ethyl ketone, and the solvent resistance was inferior to those of Examples 1 to 3.

Claims (14)

An electrodeposition coating material comprising an aqueous dispersion containing the following polyolefin resin, wherein the polyolefin resin has a number average particle diameter of 1 μm or less, and a non-volatile aqueous auxiliary agent and a charge adjustment auxiliary agent are substantially contained in the aqueous dispersion. An anionic electrodeposition paint characterized by not containing it. Polyolefin resin: composed of (A1) an unsaturated carboxylic acid or an anhydride thereof, (A2) an ethylenic hydrocarbon, and (A3) at least one compound represented by any of the following formulas (I) to (IV) A polyolefin resin in which the mass ratio of each of the constituent components (A1) to (A3) satisfies the following formulas (1) and (2).
0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1)
(A2) / (A3) = 55 / 45-99 / 1 (2)
2. An anion comprising an aqueous resin dispersion composition according to claim 1, wherein the unsaturated carboxylic acid or anhydride (A1) component is at least one selected from maleic anhydride, acrylic acid or methacrylic acid. Electrodeposition paint. The polyolefin resin aqueous dispersion according to claim 1, wherein the polyolefin resin is an ethylene-acrylic acid ester-maleic anhydride terpolymer or an ethylene-methacrylic acid ester-maleic anhydride terpolymer. Anion electrodeposition paint consisting of body. 4. The anionic electrodeposition coating composition comprising an aqueous polyolefin resin dispersion according to claim 1, wherein the melt flow rate of the polyolefin resin at 190 ° C. under a load of 2160 g is 0.1 to 250 g / 10 min. The anionic electrodeposition coating composition comprising an aqueous polyolefin resin dispersion according to claim 1, wherein the aqueous dispersion further contains an organic solvent, and the content of the organic solvent is 40% by mass or less of the aqueous dispersion. . 6. The organic solvent according to claim 5, wherein the organic solvent has at least one atom having a Pauling electronegativity of 3.0 or more in a molecule and a boiling point of 30 to 250 ° C. An anionic electrodeposition paint comprising an aqueous polyolefin resin dispersion. The aqueous dispersion further contains a basic compound, and the content of the basic compound is 0.5 to 3.0 times equivalent mol to the number of moles of carboxyl groups in the polyolefin resin. An anionic electrodeposition paint comprising an aqueous polyolefin resin dispersion. The anionic electrodeposition coating composition comprising an aqueous polyolefin resin dispersion according to claim 7, wherein the basic compound is an organic amine compound having a boiling point of 30 to 250 ° C. The anionic electrodeposition paint comprising the aqueous dispersion according to claim 8, further comprising metal ions. The anionic electrodeposition paint comprising the aqueous dispersion according to claim 9, further comprising inorganic particles having an average particle size of 0.005 to 10 µm. The anionic electrodeposition coating composition comprising an aqueous dispersion according to claim 1, further comprising 0.01 to 100 parts by mass of a crosslinking agent with respect to 100 parts by mass of the resin in the aqueous dispersion. A process for producing an anionic electrodeposition coating composition comprising an aqueous polyolefin resin dispersion, characterized by heating and stirring the following polyolefin resin, basic compound, and water as raw materials in a sealed container at a temperature of 80 to 200 ° C. . Polyolefin resin: composed of (A1) an unsaturated carboxylic acid or an anhydride thereof, (A2) an ethylenic hydrocarbon, and (A3) at least one compound represented by any one of the above formulas (I) to (IV). A polyolefin resin in which the mass ratio of each of the constituent components (A1) to (A3) satisfies the following formulas (1) and (2).
0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1)
(A2) / (A3) = 55 / 45-99 / 1 (2) An organic solvent is further used as a raw material, The manufacturing method of the anion electrodeposition coating material which consists of the polyolefin resin aqueous dispersion of Claim 12 characterized by the above-mentioned. A polyolefin resin aqueous dispersion is obtained by the method according to claim 13, and further, a solvent removal treatment is performed to reduce the organic solvent content of the aqueous dispersion. Production method.