JP2003119328A - Aqueous dispersion of polyolefin resin and method for producing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous dispersion which can readily be formed into a film at a low temperature which is excellent in transparency and water resistance and is excellent in stability in mixing with the aqueous dispersion of other polymer, a metal ion, inorganic particles or an additive such as a crosslinking agent. SOLUTION: This aqueous dispersion of a polyolefin resin comprises a polyolefin resin which is a copolymer of an unsaturated carboxylic acid or its anhydride with an ethylenic hydrocarbon and a specific compound having a structure represented by either one formula of the formulas (I) to (IV) [wherein R1 is hydrogen or methyl group; R2 is <=10C alkyl group; R3 is hydrogen or <=10C alkyl group] and contains >=0.01 mass% and <5 mass% of the unsaturated carboxylic acid or its anhydride and has (55/45) to (99/1) ratio of the ethylenic hydrocarbon to the specific compound and has <=1 μm number- average particle diameter and does not substantially contain a nonvolatile aqueous auxiliary. A method for producing the dispersion is also provided.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyolefin resin aqueous dispersion containing an olefin component as a main component.
Despite the low content of unsaturated carboxylic acid components, it has a stable pot life without adding a non-volatile hydration aid, and because it does not contain these,
It is possible to form a film with excellent water resistance without impairing the properties of the polyolefin resin, and to improve the mixing stability with other polymer aqueous dispersions, metal ions, inorganic particles, or additives such as crosslinking agents. Are better. Furthermore, the polyolefin resin aqueous dispersion of the present invention can be easily formed into a film at a low temperature, and the obtained film has excellent transparency.

[0002]

2. Description of the Related Art In recent years, the use of organic solvents has tended to be restricted from the standpoints of environmental protection, resource saving, regulation of dangerous substances by the Fire Service Act, and improvement of the work environment. It is being appreciated.

It is generally known that an aqueous dispersion of a resin having a low olefin compound content can be obtained by emulsion polymerization or suspension polymerization in the presence of an emulsifier or a compound having a protective colloid action. However, since the reaction pressure at the time of polymerization increases as the olefin content in the resin increases, it becomes difficult to obtain a stable aqueous dispersion by the above method in consideration of equipment and safety. A resin having a high olefin content is generally obtained by high-pressure radical polymerization in a high-pressure ethylene plant or the like, and usually cannot be obtained in the state of an aqueous dispersion.

On the other hand, even with a resin having a high olefin content, an aqueous polyolefin resin dispersion can be obtained by increasing the copolymerization rate of the unsaturated carboxylic acid component.
For example, an aqueous dispersion of an ethylene-unsaturated carboxylic acid copolymer resin such as an ethylene-acrylic acid copolymer resin or an ethylene-methacrylic acid copolymer resin having an unsaturated carboxylic acid content of about 20% by mass is conventionally known. In particular, when an alkali metal compound or ammonia is used, an aqueous dispersion of the resin is easy to produce and is widely used. But,
As the content of unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid copolymer resin decreases, it becomes difficult to make the resin aqueous. Japanese Patent Laid-Open Nos. 2000-72879 and 2
000-119398 discloses 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. Content of unsaturated carboxylic acid is 15% by mass
Only the above is illustrated. Further, when the content of the unsaturated carboxylic acid is less than 10% by mass, particularly less than 5% by mass of the ethylene-unsaturated carboxylic acid copolymer is dispersed in the aqueous medium, as described below, a non-volatile aqueous solubilization aid. It was very difficult to obtain an aqueous dispersion without the addition of these agents. Since the non-volatile water-solubilizing agent remains in the coating film even after drying, the characteristics of the polyolefin resin may be deteriorated.

When the content of the unsaturated carboxylic acid in the ethylene-unsaturated carboxylic acid copolymer resin is increased, water-solubilization is facilitated. However, since the amount of carboxyl groups reactive with various compounds is increased, after the production, When other additives, especially a compound having reactivity with a carboxyl group, is added, the mixing stability is significantly reduced.

As a method for aqueous dispersion of a polyolefin resin having a low unsaturated carboxylic acid content, the resin may be dissolved in an organic solvent or may be melted and liquefied in the presence of a non-volatile aqueous solubilizing agent. Mechanical dispersion is performed in an aqueous medium. For example, Japanese Patent Publication Sho-58-42
Japanese Patent No. 207 describes a method of dispersing a polyolefin resin in water by adding a carboxyl group-containing polyolefin wax as a water-solubilizing aid. In this case, addition of a low molecular weight compound such as polyolefin wax will impair the original properties of the polyolefin resin. Further, JP-A-62-252478, JP-A-5-163420, and JP-A-7-824.
JP-A No. 23-296081 and JP-A No. 9-296081 describe a method of dispersing a polyolefin resin in water by using various emulsifiers and compounds having a protective colloid action as an hydration aid. However, in such a case, the system contains a highly hydrophilic emulsifier used as an hydration aid and a compound having a protective colloid action,
Since these remain in the coating film even after drying, there is a problem that the water resistance of the formed coating film is significantly lowered. Further, a coating film containing an emulsifier or a compound having a protective colloid action is not preferable in terms of environment and hygiene because they may bleed out. That is, after drying, it is required to finely and uniformly disperse a polyolefin resin having a low unsaturated carboxylic acid content in an aqueous medium without adding a non-volatile compound that remains in the coating film. It was

[0007]

With respect to the above problems, the inventors of the present invention do not impair the properties of the polyolefin resin because the non-volatile aqueous solubilizing agent is not substantially added. Capable of forming a film with excellent water resistance, excellent film-forming properties at low temperatures, and stable mixing with other polymer aqueous dispersions, metal ions, inorganic particles, or additives such as crosslinking agents. It is intended to provide an aqueous dispersion of a polyolefin resin having excellent unsaturated properties and a low unsaturated carboxylic acid content.

[0008]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that a polyolefin resin having a specific composition is a non-volatile water-based auxiliary agent even if the unsaturated carboxylic acid content is low. The present invention has been completed by finding that it can be stably dispersed in an aqueous medium without addition of. That is, the gist of the present invention is as follows. An aqueous dispersion containing the following polyolefin resin, the number average particle size of the polyolefin resin is 1μm or less, a polyolefin characterized by substantially not containing a non-volatile hydration aid in the aqueous dispersion Aqueous resin dispersion. Moreover, the manufacturing method. Polyolefin resin: (A1) unsaturated carboxylic acid or anhydride thereof, (A2) ethylene hydrocarbon, (A3) at least one compound represented by any of the following formulas (I) to (IV) A polyolefin resin which is a copolymer having the following formulas (1) and (2) in which the mass ratio of each of the constituent components (A1) to (A3) is satisfied. 0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1) (A2) / (A3) = 55/45 to 99/1 (2)

[0009]

[Chemical 2]

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The polyolefin resin aqueous dispersion in the present invention is an aqueous dispersion containing a specific polyolefin resin and an aqueous medium, and the number average particle diameter of the polyolefin resin dispersed in the aqueous medium needs to be 1 μm or less. By using the specific polyolefin resin, the polyolefin resin can be stably maintained in the state of having a number average particle diameter of 1 μm or less in the aqueous medium even if the non-volatile water-solubilizing agent is not substantially contained.

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 based on the whole resin [(A1) + (A2) + (A3)].
Or more, less than 5 mass%, more preferably 0.1 mass% or more, 5
Less than mass%, more preferably 0.5 mass% or more, 5 mass%
It is necessary to contain less than 1% by mass, 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 (liquefy), and it is difficult to obtain a good aqueous dispersion. On the other hand, when the content of the unsaturated carboxylic acid or the anhydride thereof is 5% by mass or more, the aqueous solution is easily made, but the mixing stability with other additives may be deteriorated.

The unsaturated carboxylic acid or its anhydride 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), Specific examples thereof include acrylic acid, methacrylic acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, fumaric acid and crotonic acid, as well as half esters and half amides of unsaturated dicarboxylic acids. Of these, acrylic acid, methacrylic acid, maleic acid and maleic anhydride are preferable, and acrylic acid and maleic anhydride are particularly preferable.
The unsaturated carboxylic acid may be copolymerized in the polyolefin resin, and the form thereof is not limited, and examples thereof include random copolymerization, block copolymerization, and graft copolymerization.

The polyolefin resin used in the present invention requires the component (A3) represented by any of the following formulas (I) to (IV) as a constituent component, and this component imparts hydrophilicity to the polyolefin resin. Therefore, the (A1) component is
Even if it is less than 5% by mass, it can be hydrated without adding a non-volatile hydration aid. Ethylene hydrocarbon (A
The mass ratio (A2) / (A3) between the 2) component and the (A3) component is 55.
It is necessary to be in the range of / 45 to 99/1, 60/40 to 9
8/2 is preferable, 65/35 to 97/3 is more preferable, 70/30 to 97/3 is further preferable, and 75/25 to 97/3 is particularly preferable. .
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 of the component (A2) as a polyolefin resin are lost and the performance such as water resistance is deteriorated.

[0014]

[Chemical 3]

The ethylene hydrocarbon (A2) component constituting the polyolefin resin of the present invention includes ethylene, propylene, isobutylene, 1-butene, 1-pentene, 1
-Alkenes having 2 to 6 carbon atoms such as hexene are mentioned, and a mixture thereof 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 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) acrylic acid esters such as ethyl (meth) acrylate and butyl (meth) acrylate, maleic acid esters such as dimethyl maleate represented by the formula (II), diethyl maleate and dibutyl maleate, and formulas (Meth) acrylic acid amides represented by (III), alkyl vinyl ethers represented by formula (IV) such as methyl vinyl ether and ethyl vinyl ether, vinyl formate, vinyl acetate, vinyl propionate, vinyl pivalate, versatic Vinyl alcohols such as vinyl acetate and vinyl alcohol obtained by saponifying vinyl esters with a basic compound, And the like, and a mixture thereof can also be used. Among these, the (meth) acrylic acid ester represented by the formula (I) is 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 composed of ethylene, methyl acrylate or ethyl acrylate, and maleic anhydride. Here, the acrylic acid ester unit may hydrolyze a small part of the ester bond to be converted to an acrylic acid unit when the resin is made water-based, which will be described later. It suffices that the ratio of each constituent component in consideration of the change is within the specified range.

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

The polyolefin resin used in the present invention may be copolymerized with a small amount of other monomers. Examples thereof 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 0.01 to 500 g / 10 minutes, preferably 0.1 to 300, at 190 ° C. and a load of 2160 g, which is an index of the molecular weight.
g / 10 minutes, more preferably 0.1 to 250 g / 10 minutes, still more preferably 0.5 to 200 g / 10 minutes, and most preferably 1 to 100 g / 10 minutes. If the melt flow rate of the polyolefin resin is less than 0.01 g / 10 minutes, it becomes difficult to make the resin water-soluble, and it is difficult to obtain a good aqueous dispersion. On the other hand, the melt flow rate of polyolefin resin is
When it exceeds 500 g / 10 minutes, the coating film 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 in consideration of the gist of the present invention,
It is preferable not to use an emulsifier or protective colloid. Generally, it is obtained by high-pressure radical copolymerization of a monomer constituting a polyolefin resin in the presence of a radical generator.
Further, the unsaturated carboxylic acid or its anhydride may be graft-copolymerized (graft-modified).

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, you may contain the basic compound mentioned later.

The number average particle size (hereinafter, mn) of the polyolefin resin particles dispersed in the aqueous dispersion of the present invention.
Is required to be 1 μm or less from the viewpoint of improving the storage stability of the aqueous dispersion, and from the viewpoint of low temperature film-forming property.
0.5 μm or less is preferable, 0.3 μm or less is more preferable, and
It is more preferably 2 μm or less, and most preferably less than 0.1 μm. Furthermore, regarding the weight average particle size (hereinafter, mw),
1 μm or less is preferable, 0.5 μm or less is more preferable, and 0.3
It is more preferably not more than μm, most preferably not more than 0.2 μm. The dispersity of the particles (mw / mn) is preferably 1 to 3 from the viewpoint of storage stability of the aqueous dispersion and low-temperature film-forming property, and 1 to
2.5 is more preferable, and 1-2 is particularly preferable.

The resin content in the aqueous dispersion of the present invention can be appropriately selected depending on the film forming conditions, the thickness and performance of the desired resin film, and is not particularly limited, but the viscosity of the coating composition can be adjusted. From the viewpoint of maintaining a proper amount and developing a good film-forming ability, 1 to 60 mass% is preferable, and 3 to 55
Mass% is more preferable, 5 to 50 mass% is further preferable, and 10 to 45 mass% is particularly preferable.

The aqueous dispersion of the present invention is characterized in that it does not substantially contain a non-volatile aqueous solubilizing agent. Even without using these, a polyolefin resin having a number average particle diameter of 1 μm or less can be stably prepared in an aqueous medium. Can be maintained. The non-volatile water-solubilizing agent remains in the polyolefin resin even after the film is formed, and plasticizes the film to deteriorate the properties of the polyolefin resin, such as water resistance. Since the present invention contains substantially no non-volatile water-solubilizing agent, it has excellent coating properties, particularly water resistance. Here, "water-based auxiliaries"
The term "nonvolatile" refers to a chemical or compound added in the production of an aqueous dispersion for the purpose of promoting hydration or stabilizing the aqueous dispersion, and "nonvolatile" does not have a boiling point at normal pressure. Or, it means that it has a high boiling point (for example, 300 ° C. or higher) at normal pressure. "Substantially free of non-volatile aqueous auxiliaries"
Means that the non-volatile aqueous auxiliaries are not positively added to the system, and as a result, they are not contained. It is particularly preferable that the content of such a non-volatile aqueous solubilizing 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 effect of the present invention is not impaired.

Examples of the non-volatile aqueous solubilizing agent in the present invention include emulsifiers, compounds having a protective colloid action, modified waxes, acid-modified compounds having a high acid value, and water-soluble polymers described below. Examples of emulsifiers include cationic emulsifiers, anionic emulsifiers, nonionic emulsifiers, and amphoteric emulsifiers. In addition to those generally used for emulsion polymerization, surfactants are also included. For example, as the anionic emulsifier, sulfate ester salt of higher alcohol, higher alkyl sulfonate, higher carboxylate,
Examples thereof include alkylbenzene sulfonate, polyoxyethylene alkyl sulphate salt, polyoxyethylene alkyl phenyl ether sulphate salt, vinyl sulfosuccinate, and the like. Nonionic emulsifiers include polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, and polyethylene. Glycol fatty acid ester, ethylene oxide propylene oxide block copolymer, polyoxyethylene fatty acid amide,
Examples thereof include compounds having a polyoxyethylene structure such as ethylene oxide-propylene oxide copolymers and sorbitan derivatives such as polyoxyethylene sorbitan fatty acid esters, and examples of amphoteric emulsifiers include lauryl betaine and lauryl dimethylamine oxide.

Compounds having a protective colloid action, modified waxes, acid-modified compounds having a high acid value, and water-soluble polymers include polyvinyl alcohol, carboxyl group-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, modified starch. , Polyvinylpyrrolidone, polyacrylic acid and its salts, carboxyl group-containing polyethylene wax, carboxyl group-containing polypropylene wax,
Number-average molecular weight of carboxyl group-containing polyethylene-propylene wax or the like is usually 5000 or less, acid-modified polyolefin waxes and salts thereof, acrylic acid-maleic anhydride copolymers and salts thereof, styrene- (meth) acrylic acid copolymers , Ethylene- (meth) acrylic acid copolymer,
Isobutylene-maleic anhydride alternating copolymer, (meth) acrylic acid-unsaturated carboxylic acid content such as (meth) acrylic acid ester copolymer 10 mass% or more carboxyl group-containing polymer and salts thereof, polyitaconic acid and Examples thereof include salts, water-soluble acrylic copolymers having an amino group, gelatin, gum arabic, casein and the like, which are generally used as dispersion stabilizers for fine particles.

In the aqueous dispersion of the present invention, the carboxyl group in the polyolefin resin is preferably neutralized with a basic compound. The electric repulsive force between the carboxyl anions generated by the neutralization prevents aggregation among the fine particles and imparts stability to the aqueous dispersion. The basic compound used for making the aqueous solution may be one that can neutralize the carboxyl group. Therefore, the basic compound added for such a purpose can be said to be an hydration aid, 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 which volatilizes at the time of forming a film is preferable from the viewpoint of the water resistance of the film, and among them, an organic amine compound having a boiling point of 30 to 250 ° C., more preferably 50 to 200 ° C. preferable. When the boiling point is less than 30 ° C., the ratio of volatilization at the time of water-solubilization of the resin, which will be described later, increases, and water-hydration may not be completely progressed. When the boiling point exceeds 250 ° C, it becomes difficult to scatter 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,
Examples thereof include N-ethylmorpholine. The addition amount of the basic compound is preferably 0.5 to 3.0 times equivalent to the carboxyl group in the polyolefin resin, 0.8
˜2.5 times equivalents are more preferable, and 1.01 to 2.0 times equivalents are particularly preferable. If it is less than 0.5 times equivalent, the effect of adding the basic compound is not observed, and if it 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 hydration in order to accelerate hydration of the polyolefin resin and reduce the dispersed particle size. The amount of the organic solvent used is preferably 40% by mass or less in the aqueous medium,
It is 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, which is one of the purposes of the present invention (environmental protection).
In addition to deviating from the above, the stability of the aqueous dispersion may decrease depending on the organic solvent used.

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, but this operation is also performed in the aqueous dispersion of the present invention. The amount of organic solvent in the aqueous dispersion may be appropriately reduced within the above range by 10% by mass.
It can be the following, and if it is 3% by mass or less, it is environmentally preferable. In order to remove the organic solvent by stripping, it is necessary to take measures in the production process such as increasing the decompression degree of the equipment and lengthening the operating time.Therefore, the lower limit of the amount of organic solvent is 0.01 in consideration of such productivity. It is about% by 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 does not cause any particular problem. The aqueous dispersion of the present invention, even if the amount of organic solvent is reduced by stripping,
There is no particular effect on the performance and it can be favorably used in various applications.

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

As the organic solvent, an atom having a Pauling electronegativity of 3.0 or more (specifically, oxygen, nitrogen, fluorine, chlorine) is used in the molecule in order to obtain a good aqueous dispersion. It is preferable to use one having more than one. 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-butanol.
Amyl alcohol, isoamyl alcohol, sec-amyl alcohol, tert-amyl alcohol, 1-ethyl-1-propanol, 2-methyl-1-butanol, n-hexanol, cyclohexanol and other alcohols, methyl ethyl ketone, methyl isobutyl ketone, ethyl Butyl ketone, cyclohexanone, isophorone and other ketones, tetrahydrofuran, dioxane and other ethers, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate, acetic acid-3- Esters such as methoxybutyl, methyl propionate, ethyl propionate, diethyl carbonate, dimethyl carbonate, ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether Ethylene glycol monopropyl ether, ethylene glycol monobutyl ether,
Ethylene glycol ethyl ether acetate, 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, glycol derivatives such as propylene glycol methyl ether acetate,
Furthermore, 3-methoxy-3-methylbutanol, 3-
Methoxybutanol, acetonitrile, dimethylformamide, dimethylacetamide, diacetone alcohol, ethyl acetoacetate and the like, among them, the boiling point is 30 ~
A temperature of 250 ° C is preferable, and a temperature of 50 to 200 ° C is particularly preferable. You may use these organic solvents in mixture of 2 or more types. When the boiling point of the organic solvent is lower than 30 ° C., the rate of volatilization at the time of hydration of the resin increases, and the hydration efficiency may not be sufficiently increased. An organic solvent having a boiling point of higher than 250 ° C. is difficult to be scattered from the resin coating by drying, and the water resistance of the coating may be deteriorated.

Among the above organic solvents, ethanol, n-propanol, and n-propanol are highly effective in promoting the water-solubilization of the resin and can easily remove the organic solvent from the aqueous medium.
Isopropanol, n-butanol, methyl ethyl ketone, cyclohexanone, tetrahydrofuran, 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 polyolefin resin aqueous dispersion of the present invention has excellent film-forming properties at low temperatures and forms a highly transparent film even at a temperature lower than the melting point of the resin being dispersed (more specifically, 25 ° C. or lower). can do. Here, the “haze (haze value)” of the coated film coated with the aqueous dispersion of polyolefin resin is used as a measure of film-forming property and transparency.
A film with a haze of 2.0 to 5.0 (%) is used as the base material, and the temperature at which the film is coated with a polyolefin resin aqueous dispersion so that the coating film thickness after drying is 2 μm in an atmosphere of 5 ° C or 25 ° C. Dry at the same temperature as. In the present invention, the haze of the entire coated film thus obtained is 10.0 (%) or less. The closer the haze of the entire coat film to the haze of the base film, the higher the transparency. When the haze was 10.0 (%) or less, the transparency of the coated film was visually good, and it was determined that the aqueous dispersion could be formed into a film at 5 ° C or 25 ° C.

Next, the method for producing the polyolefin resin aqueous dispersion will be described. The method for obtaining the polyolefin resin aqueous dispersion of the present invention is not particularly limited, for example, each component described above, that is, a polyolefin resin of a specific composition, a basic compound, water, further organic solvent if necessary, A method of heating and stirring in a container that can be closed is preferably used, 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 hydration aid such as an emulsifier component or a compound having a protective colloid action.

Any container may be used as long as it has a tank into which a liquid can be charged and can appropriately stir the mixture of the aqueous medium and the resin powder or granules 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,
It is preferable to use a device capable of applying a pressure of 0.1 MPa or more. The stirring method in the present invention, the rotation speed of the stirring is not particularly limited, sufficient waterification is achieved even at low speed stirring such that the resin becomes a floating state in the aqueous medium, high speed stirring (for example 1000 rpm or more) is not essential. Absent. Therefore, it is possible to manufacture the aqueous dispersion with a simple apparatus.

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

An aqueous medium consisting 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 the mixture is preferably stirred and mixed at a temperature of 40 ° C. or lower. Then, increase the temperature in the bath to 80-20.
0 ℃, preferably 90 ~ 200 ℃, more preferably 100 ~ 190
While maintaining the temperature of ° C., to make the polyolefin resin sufficiently aqueous, preferably by continuing stirring for 5 to 120 minutes,
Thereafter, the aqueous dispersion can be obtained by preferably cooling to 40 ° C. or lower with stirring. The temperature in the tank is 80
When the temperature is lower than 0 ° C, it becomes difficult to make the polyolefin resin aqueous. If the temperature in the tank exceeds 200 ° C, the molecular weight of the polyolefin resin may decrease. As a method for heating the inside of the tank, heating from the outside of the tank is preferable, and 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 method for cooling the inside of 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 that, a jet crushing treatment may be further performed if necessary. The jet pulverization treatment here means that a fluid such as an aqueous dispersion of polyolefin resin is ejected from a fine hole such as a nozzle or a slit under high pressure, and the resin particles are collided with each other or with the collision plate and the like. APV is a method to further reduce the size of resin particles by mechanical energy.
Examples include GAULIN's homogenizer and Mizuho Kogyo's microfluidizer M-110E / H.

As a method for adjusting the solid content concentration of the thus obtained aqueous dispersion, for example, a method of distilling off the aqueous medium or diluting it with water so that the desired solid content concentration is obtained. Can be mentioned.

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

The aqueous yield in the production of the aqueous dispersion can be known by the amount of coarse particles remaining in the obtained aqueous dispersion. Specifically, 300 aqueous dispersion
Pressure filtration (air pressure 0.2 MPa) with a 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. The hydration yield in the present invention may be slightly lowered depending on the conditions, but is generally very good, and the hydration is achieved with few coarse particles remaining.

The polyolefin resin aqueous dispersion thus produced has excellent 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, a cross-linking agent or the like can be added.

The aqueous dispersion of another 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 Aqueous dispersions of 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, epoxy resins, etc. be able to. These are 2
You may use it in mixture of 2 or more types.

Usually, in an aqueous dispersion, when the fine particles are stabilized by an electric repulsive force such as a carboxyl anion, the addition of various metal ions causes the fine particles to agglomerate and the stability of the dispersion liquid is improved. It is well known that it decreases. On the other hand, the aqueous dispersion of the present invention is excellent in stability even when a metal ion is added 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, but for example, lithium, sodium, calcium, barium, magnesium, zinc, copper, cobalt,
Aluminum or the like can be used. These are 2
You may use it in mixture of 2 or more types. Further, the addition amount is also not particularly limited, it can be used in a wide range of addition amount, when used as a coating agent, as a metal ion, preferably 10 to 90 mol% relative to the carboxyl group amount of the polyolefin resin, 20 ~ 80 mol% is more preferable.

The inorganic particles include 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. Can be added. The average particle size of these inorganic particles is 0.005 ~ 10 μm from the viewpoint of stability of the aqueous dispersion.
Is preferable, and more preferably 0.005 to 5 μm. The inorganic particles may be used as a mixture of two or more kinds.

In order to further improve various coating performances such as water resistance, 0.01 to 100 parts by weight, preferably 0.1 to 60 parts by weight of a crosslinking agent is added to 100 parts by weight of the resin in the aqueous dispersion. You can When the amount of the cross-linking agent added is less than 0.01 parts by mass, the degree of improvement in coating film performance is small, and when it exceeds 100 parts by mass, the performance such as workability deteriorates. As the cross-linking agent, a self-crosslinking cross-linking agent, a compound having a plurality of functional groups that react with a carboxyl group in the molecule,
A metal complex or the like having a polyvalent coordination site 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. Further, these cross-linking agents may be used in combination.

Furthermore, if necessary, the aqueous dispersion of the present invention may be added with a leveling agent, an antifoaming agent, an anti-armpit agent, a pigment dispersant,
The aqueous dispersion of the present invention can be used as a coating agent or paint by adding various chemicals such as an ultraviolet absorber and pigments or dyes such as titanium oxide, zinc oxide, and carbon black. It is also possible to add an organic or inorganic compound other than the above to the aqueous dispersion as long as the stability of the aqueous dispersion is not impaired.

Aqueous dispersions of other polymers shown above, metal ions, inorganic particles, crosslinking agents, leveling agents, defoaming agents,
Two or more kinds of additives such as an anti-armpitting agent, a pigment dispersant, an ultraviolet absorber, a pigment or a dye 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. For example, it can be used for metal, glass, plastic moldings, films, papers and the like.

Next, a method of using the aqueous dispersion of the present invention will be described. Since the aqueous dispersion of the present invention is excellent in film forming ability, known film forming methods such as gravure roll coating, reverse roll coating, wire bar coating, lip coating, air knife coating, curtain flow coating, spray coating and dipping. Uniformly coats various substrate surfaces by coating, brush coating, etc., and sets them at around room temperature if necessary, and then heats them for drying or drying and baking to obtain various uniform resin coatings. It can be formed in close contact with the surface of the base material. As a heating device at this time, an ordinary hot air circulation type oven, an infrared heater or the like may be used. The heating temperature and the heating time are appropriately selected depending on the characteristics of the substrate to be coated, the type of the curing agent described below, the compounding amount, and the like. Is preferably from 30 to 250 ° C., more preferably from 60 to 230 ° C., particularly preferably from 80 to 210 ° C., as the heating time, preferably from 1 second to 20 minutes, more preferably from 5 seconds to 15 minutes, and from 5 seconds to Ten
Minutes are particularly preferred. When a cross-linking agent is added, it is desirable to appropriately select the heating temperature and time depending on the type of the cross-linking agent in order to sufficiently proceed the reaction between the carboxyl group in the polyolefin and the cross-linking agent.

The thickness of the resin film formed using the aqueous dispersion of the present invention is appropriately selected depending on its application, but is preferably 0.01 to 100 μm, and 0.1
˜50 μm is more preferred, and 0.2-30 μm is particularly preferred.
By forming the resin film so that the thickness of the resin film is within the above range, a resin film having excellent uniformity can be obtained. In addition, in order to adjust the thickness of the resin coating, in addition to appropriately selecting the apparatus used for coating and its use conditions, an aqueous dispersion having a concentration suitable for the intended thickness of the resin coating is used. It is preferable. The concentration at this time can be adjusted by the composition charged at the time of preparation. Further, the once-prepared aqueous dispersion may be adjusted by appropriately diluting or concentrating it.

[0057]

EXAMPLES The present invention will now be described in detail with reference to Examples, but the present invention is not limited thereto. Various properties were measured or evaluated by the following methods. (1) Constitution of polyolefin resin ¹ H-NMR analysis (manufactured by Varian Co., Ltd., 300 MHz) was carried out in orthodichlorobenzene (d ₄ ) at 120 ° C. for determination. (2) Residual amount of ester group after hydration After hydration of the aqueous polyolefin dispersion after hydration at 150 ° C., it was placed in orthodichlorobenzene (d ₄ ) at 120 ° C. for ¹ H.
-NMR analysis (manufactured by Varian Co., Ltd., 300 MHz) was performed, and the residual rate (%) of the ester group was determined by setting the amount of the ester group of the acrylic acid ester before hydration as 100. (3) Solid Content Concentration of Polyolefin Resin Aqueous Dispersion An appropriate amount of the polyolefin dispersion was weighed, and this was heated at 150 ° C. until the mass of the residue (solid content) reached a constant amount, and the polyolefin resin solid content concentration was determined. (4) Viscosity of polyolefin resin aqueous 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 size of polyolefin resin particles, Microtrack particle size analyzer UPA150 (MODE, manufactured by Nikkiso Co., Ltd.
L No. 9340) was used to determine the number average particle diameter and the weight average particle diameter. (6) Aqueousification yield The aqueous dispersion after hydration is pressurized and filtered with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) (air pressure 0.2
(MPa), the mass of the resin remaining on the filter was measured, and the yield was calculated from the mass of the charged resin. (7) Appearance of aqueous dispersion The color tone of the aqueous dispersion was evaluated by visual observation. (8) The water-resistant aqueous dispersion of the coating film was applied onto a biaxially stretched PET film (Emblet PET12 manufactured by Unitika Ltd., thickness 12 μm), and the coating film thickness after drying was approximately
It was coated with a Mayer bar so as to have a thickness of 1 μm and dried at 200 ° C. for 2 minutes. The coated film thus prepared was immersed in tap water for 1 day, and then the presence or absence of dissolution or peeling of the coating layer was visually evaluated. ○: No change in appearance. X: The coat layer is dissolved or peeled off. (9) Pot life The appearance of the polyolefin resin aqueous dispersion left at room temperature for 90 days was evaluated according to the following three grades. ○: No change in appearance. Δ: Viscosity increased. X: Solidification, aggregation and generation of precipitates are observed. (10) Mixing stability of polyolefin resin aqueous dispersion and other additives When the polyolefin resin aqueous dispersion and other additives are mixed and left at room temperature, the appearance of the mixed liquid (thickening, solidification) , Aggregation and generation of precipitates). (11) Content of organic solvent in polyolefin resin aqueous 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 (60/8
0 mesh), column size: diameter 3 mm x 3 m, sample input temperature (injection temperature): 150 ° C, column temperature: 60
C., internal standard substance: n-butanol], the aqueous dispersion or the aqueous dispersion diluted with water was directly put into the apparatus to determine the content of the organic solvent. Detection limit is 0.01
It was mass%. (12) Haze (Haze value) "Haze (%)" was measured according to JIS K7105 using NDH2000 "turbidity, haze meter" manufactured by Nippon Denshoku Industries Co., Ltd. PET film with haze of 2.8% (Emblet manufactured by Unitika Ltd.
PET12, thickness 12μm) was coated with a polyolefin resin aqueous dispersion using a Mayer bar so that the coating film thickness after drying in an atmosphere of 5 ° C or 25 ° C would be 2μm.
The coated film was prepared by leaving it to stand at the same temperature as the coating temperature for 3 days and drying it. The haze of the entire coated film thus produced was measured. (13) Melt flow rate (MFR) of polyolefin resin after hydration The aqueous polyolefin dispersion was placed in a glass petri dish,
It was dried at 0 ° C. for 6 hours. Of the obtained polyolefin resin
MFR was measured by the method described in JIS 6730 (190 ° C, 2160 g load). (14) Evaluation of coating adhesion Nylon 6 film with a thickness of 150 μm or P with a thickness of 120 μm
The coat thickness after drying various coating liquids on ET film is 2
It was coated with a Mayer bar to a thickness of μm and dried at 120 ° C. for 2 minutes. After standing at room temperature for 24 hours, JIS K5400 8.5.
The adhesion test was performed by the method of 2. Cut the coat layer 1
mm × 1 mm × 100 cross-cut portions were prepared, peeled off with an adhesive tape, and evaluated by the number of pieces remaining without peeling in 100 cross-cuts. "N / 100" indicates that n out of 100 grids remain without peeling, and "100/10
"0" indicates that the adhesiveness is the best without any peeling.

The composition of the resin used is shown in Table 1. In addition,
The melting points of the resins listed in Table 1 are the values measured by DSC (measurement device: Perkin-Elmer DSC-7),
The melt flow rate is the method described in JIS 6730 (190 ℃, 21
It is the value measured under a load of 60 g.

[0059]

[Table 1]

Example 1 60.0 g of polyolefin resin (A) was prepared using a stirrer equipped with a pressure-resistant 1 L glass container with a heater.
(Bondyne HX-8210, manufactured by Sumitomo Chemical Co., Ltd.), 30.0 g of ethylene glycol-n-butyl ether (hereinafter, Bu-E
G), 3.9 g (1.2 times equivalent to the carboxyl group of maleic anhydride in the resin) N, N-dimethylethanolamine (hereinafter, DMEA) and 206.1 g of distilled water were charged in a glass container, and a stirring blade was added. When stirring was performed at a rotation speed of 300 rpm, precipitation of resin particles was not observed at the bottom of the container,
It was confirmed to be in a floating state. Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, the temperature in the system was kept at 140 ° C., and the mixture was further stirred for 20 minutes. After that, put it in a water bath and cool it to room temperature (about 25 ° C) while stirring at a rotation speed of 300 rpm, and then press-filter (air pressure 0.2 MPa) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave). A milky white uniform polyolefin resin aqueous dispersion E-1 was obtained. Various properties 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 their distribution was one peak, and the polyolefin resin was dispersed in the aqueous medium in a good state. Furthermore, the pot life of the aqueous dispersion was 90 days or more. The residual ester group of the resin after hydration was 100%, and ethyl acrylate was not hydrolyzed. The ester group residual ratio was 100%, which did not change even after standing for 90 days at room temperature. Furthermore, the MFR of the resin after hydration was 200 g / 10 minutes, and there was no decrease in the molecular weight. The haze of the coated film obtained by drying this aqueous dispersion in the atmosphere of 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 added was changed as shown in Table 2. Various properties of the aqueous dispersion are shown in Table 2.

Example 3 The type of amine added was triethylamine (hereinafter referred to as TE
Aqueous dispersion E-3 was prepared in the same manner as in Example 1 except that A) was used.
Got Various properties of the aqueous dispersion are shown in Table 2.

Example 4 The same as Example 1 except that the type of amine to be added was TEA, the type of organic solvent to be added was isopropanol (hereinafter, IPA), and the addition amount was changed as shown in Table 2. By the method, an aqueous dispersion E-4 was obtained. Various properties of the aqueous dispersion are shown in Table 2. The residual ester group ratio of the resin after hydration was 98%, and 2% of ethyl acrylate was hydrolyzed. The ester group residual ratio was 98% at room temperature for 90 days and unchanged after being left standing.

Example 5 The same as Example 1 except that the type of amine added was TEA, the type of organic solvent added was ethanol (hereinafter EtOH), and the addition amount was changed as shown in Table 2. By the method, an aqueous dispersion E-5 was obtained. Various properties 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 added was changed as shown in Table 2. Various properties of the aqueous dispersion are shown in Table 2.

Example 7 The type of basic compound to be added was ammonia (25% NH 3
Aqueous dispersion E was prepared in the same manner as in Example 1 except that ( ₃ water) was used.
Got -7. Various properties 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 adjusted to 30% by mass. Various properties of the aqueous dispersion are shown in Table 2.

Example 9 Aqueous dispersion was carried out 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. Got body E-9. Various properties of the aqueous dispersion are shown in Table 2.

Example 10 The same as 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 the amine and the organic solvent were changed as shown in Table 2. Aqueous dispersion E-10 was obtained by the method of. Table 2 shows various properties of the aqueous dispersion.
It was shown to.

Examples 11 and 12 Example 1 was repeated except that the polyolefin resin (C) (Bondaine 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. Aqueous dispersions E-11 and E-12 were obtained in the same manner as in. Various properties of the aqueous dispersion are shown in Table 2.

Example 13 Same as Example 1 except that the polyolefin resin (D) (Bondaine LX-4110, manufactured by Sumitomo Chemical Co., Ltd.) was used, and the kinds and addition amounts of the amine and the organic solvent were changed as shown in Table 2. Aqueous dispersion E-13 was obtained by the method of. Table 2 shows various properties of the aqueous dispersion.
It was shown to. The ester group residual ratio of the resin after hydration is
95% and 5% of ethyl acrylate was hydrolyzed. The ester group residual ratio was 95%, which was unchanged even after standing for 90 days at room temperature.

[0072]

[Table 2]

Comparative Example 1 The same method as in Example 1 was carried out except that the polyolefin resin (E) (Escor TR-5100, manufactured by Exxon Chemical Co., Ltd.) was used, but coarse particles were obtained by stirring at 140 ° C. for 20 minutes. Was visually observed. Therefore, raise the system temperature to 160 ° C and
After stirring for 0 minutes, the presence of coarse particles was still visually observed. After cooling to room temperature, pressure filtration (pneumatic pressure) with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave)
However, 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) as a polyolefin resin containing no compound (A3) (manufactured by Aldrich, maleic anhydride 3% by mass, viscosity at 140 ° C. is 1700 to 4500 cps)
Using (F), the same method as in Example 1 was carried out except that the kind and addition amount of the amine and the organic solvent were changed as shown in Table 3. However, even if the mixture was stirred at 140 ° C. for 20 minutes, coarse particles were generated. Presence was visually observed. Then, the temperature inside the system was raised to 160 ° C. and 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 observed on the filter. The resin could not be made water-based substantially.

Comparative Example 3 60.0 g of polyolefin resin (A) was prepared using a stirrer equipped with a pressure-tight 1 L glass container with a heater.
(Bondaine HX-8210, manufactured by Sumitomo Chemical Co., Ltd.), 4.5 g (1.2 times equivalent to carboxyl group of maleic anhydride in resin) TEA, 6.0 g of polyoxyethylene polyoxypropylene glycol as an emulsifier, and 229.5 When g of distilled water was charged in a glass container and stirred with the stirring blade rotating at 300 rpm, precipitation of resin particles was not observed at the bottom of the container, and it was confirmed that the resin particles were in a floating state.
Therefore, while maintaining this state, the heater was turned on and heated after 10 minutes. Then, maintain the system temperature at 180 ° C for another 2
Stir for 0 minutes. Then, soak it in a water bath and rotate at a speed of 300 rp.
While stirring as it is, cool to room temperature (about 25 ℃), then 300
I tried to filter under pressure (air pressure 0.2MPa) with a mesh stainless steel filter (wire diameter 0.035mm, plain weave), but it caused clogging. Thus, a milky white polyolefin resin aqueous dispersion H-3 was obtained without filtration. Various properties of the aqueous dispersion are shown in Table 3.

Comparative Example 4 The same method as in Example 1 was carried out except that no organic solvent was added, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Then, the temperature inside the system was raised to 160 ° C. and 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 observed on the filter. The resin could not be made water-based substantially.

Comparative Example 5 Example except that the polyolefin resin (B) (Bondaine HX-8290, manufactured by Sumitomo Chemical Co., Ltd.) was used without adding an organic solvent, and the kind and amount of amine to be added were changed as shown in Table 3. The same method as in Example 1 was carried out, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Therefore, set the system temperature to 160
The temperature was raised to 0 ° C. and 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 observed on the filter. The resin could not be made water-based substantially.

Comparative Example 6 The same procedure as in Example 1 was carried out except that no amine was added, but the presence of coarse particles was visually observed even after stirring at 140 ° C. for 20 minutes. Then, the temperature inside the system was raised to 160 ° C. and 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 observed on the filter. The resin could not be made water-based substantially.

[0079]

[Table 3]

Example 14 Polyolefin Resin Aqueous Dispersion E-1 Obtained in Example 1
And an aqueous dispersion of another polymer. As the aqueous dispersion of the polymer, a polyurethane aqueous dispersion (Adekabon Titer HUX-380, manufactured by Asahi Denka Co., Ltd.) was used. E-1 was stirred, and 50 parts by mass of the above aqueous dispersion was added to 100 parts by mass of the solid content of E-1 in terms of solid content, and stirred at room temperature for 30 minutes (referred to as M-1). . The mixing stability of the obtained liquid is shown in Table 4.
Shown in.

Examples 15 to 19 Aqueous dispersion of polyolefin resin E- obtained in Example 10
10 and the cross-linking agent were mixed. As a cross-linking agent, a melamine compound (Cymel 327, manufactured by Mitsui Cytec, Example 1
5), an epoxy compound (Denacol EX-313, manufactured by Nagase Kasei Kogyo KK, Example 16 and Denacol EX-1310, manufactured by Nagase Kasei Kogyo KK, Example 17), an oxazoline group-containing compound (Epocros WS-700, Nippon Shokubai) Company, Example 1
8), and carbodiimide compounds (carbodilite E-0
2. Example 19) manufactured by Nisshinbo Co., Ltd. was used. E-10 was stirred, and the amount of the above-mentioned cross-linking agent in terms of solid content shown in Table 4 was added to 100 parts by mass of solid content of E-10, and the mixture was stirred at room temperature for 30 minutes. Table 4 shows the mixing stability of the obtained liquids (each designated as M-2 to M-6).

Example 20 Polyolefin Resin Aqueous Dispersion E-1 Obtained in Example 1
10 parts by weight of a layered inorganic compound (Kunipia F, manufactured by Kunimine Industries Co., Ltd.) per 100 parts by weight of solid content, and glass beads 250
The mass parts were mixed, shaken and dispersed with a paint shaker for 1 hour, and then the glass beads were removed. Obtained liquid (M
-7) is shown in Table 4.

Example 21 Instead of the layered inorganic compound, magnesium oxide (particle size: 0.
Example 19 except that 01 μm, manufactured by Wako Pure Chemical Industries, Ltd.) was used.
The same method was used. The mixing stability of the obtained liquid (designated as M-8) is shown in Table 4.

Example 22 Polyolefin Resin Aqueous Dispersion E-1 Obtained in Example 1
In addition, 30 against the amount of carboxyl groups of the polyolefin resin
Mol% sodium chloride was added, and the mixture was stirred at room temperature for 30 minutes. The mixing stability of the obtained liquid (designated as M-9) is shown in Table 4.

[0085]

[Table 4]

Example 23 250 g of E-10 and 85 g of distilled water were charged into a 1 L 2-neck round bottom flask, a mechanical stirrer and a Liebig type condenser were installed, and the flask was heated in an oil bath to distill the aqueous medium. I left. When about 90 g of the aqueous medium was distilled off, heating was stopped and the mixture was cooled to room temperature. After cooling, the liquid component in the flask was subjected to pressure filtration (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. . Distilled water was added to this filtrate with stirring to adjust the solid content concentration to 20.0 mass%. The content of the organic solvent (IPA) in this aqueous dispersion was 0.4% by mass. Further, visually observing the appearance of this aqueous dispersion, it is uniform without precipitation or layer separation, the number average particle diameter, the weight average particle diameter is 0.070μm, 0.092μm, respectively, its distribution It was also one mountain. Moreover, the appearance was stable even when left at room temperature for 90 days. The haze of the coated film obtained by drying this aqueous dispersion in the 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 type condenser were installed, and the flask was heated in an oil bath to distill the aqueous medium. I left. After distilling off about 105 g of the aqueous medium,
The heating was terminated and the mixture was cooled to room temperature. After cooling, the liquid components in the flask are pressure filtered with a 300 mesh stainless steel filter (wire diameter 0.035 mm, plain weave) (air pressure 0.2 MPa).
Then, the solid content concentration of the filtrate was measured and found to be 20.4% by mass. Distilled water was added to this filtrate with stirring to adjust the solid content concentration to 20.0 mass%. The content of the organic solvent (IPA) in this aqueous dispersion was 1.0% by mass. Further, visually observing the appearance of this aqueous dispersion, it is uniform without precipitation or layer separation, number average particle diameter, weight average particle diameter of 0.094μm, 0.148 respectively.
It was μm, and its distribution was one mountain. Moreover, the appearance was stable even when left at room temperature for 90 days. The haze of the coated film obtained by drying this aqueous dispersion in the atmosphere of 5 ° C. and 25 ° C. was 3.3%, and the transparency was good.

Comparative Examples 7 to 9 Using a stirrer equipped with a pressure-tight 1 L glass container equipped with a heater, 60.0 g of ethylene-acrylic acid copolymer resin (Primacol 5980I, acrylic acid 20% by mass Combined, manufactured by Dow Chemical Co., Ltd.) (G), 17.7 g (1.05 times equivalent to the carboxyl group of acrylic acid in the resin)
TEA and 222.3 g of distilled water were charged into a glass container and stirred with the stirring blade rotating at 300 rpm. No precipitation of resin granules was observed at the bottom of the container, confirming that it was in a floating state. Was done. So while keeping this state,
After 10 minutes, the heater was turned on and heated. Then, the temperature in the system was kept at 100 to 105 ° C., and the mixture was further stirred for 20 minutes. After that, put it in a water bath and cool it to room temperature (about 25 ° C) while stirring at a rotation speed of 300 rpm, and then press-filter (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. S-1
Is agitated, and with respect to 100 parts by mass of the solid content of S-1, a polyurethane aqueous dispersion (Adekabon Titer HUX-380, manufactured by Asahi Denka Co., Ltd., Comparative Example 7) and an epoxy compound (Denacol EX-313) are used. Comparative Example 8) manufactured by Nagase Chemical Industry Co., Ltd., and Denacol EX-1310, manufactured by Nagase Chemical Industry Co., Ltd. Comparative Example 9).
Was added in an amount shown in Table 4 in terms of solid content, and the mixture was added at room temperature for 30 minutes,
It was stirred. Table 4 shows the mixing stability of the obtained liquid.

Table 5 shows the results of the adhesion test conducted on the coating solutions E-1, E-9 and M-1 to M-9.

[0090]

[Table 5]

[0091]

EFFECTS OF THE INVENTION By using a specific polyolefin resin, it is possible to stabilize an aqueous dispersion of a polyolefin resin having a low unsaturated carboxylic acid content and a large amount of olefin components without using a non-volatile hydration aid. Can be obtained. Since the coating film obtained from this aqueous dispersion does not contain a non-volatile hydration aid, it does not impair the original properties of the polyolefin resin and is particularly excellent in water resistance. Moreover, the aqueous dispersion of the present invention is an aqueous dispersion of another polymer,
Since it has excellent mixing stability with additives such as metal ions, inorganic particles, or a crosslinking agent, it can be used for various purposes. Furthermore, the polyolefin resin aqueous dispersion of the present invention can be easily formed into a film at a low temperature, and the obtained film has excellent transparency.

Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08K 5/17 C08F 220: 18 // (C08F 210/00 220: 56 222: 00 C08F 216: 00 220: 18) C08J 3/03 (C08F 210/00 222: 00 220: 56) (C08F 210/00 222: 00 216: 00) (72) Inventor Hiroshi Kajimaru 23 Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Institute F Terms (reference) 4F070 AA13 AA32 AA35 AA37 AB21 AC46 BA02 BA04 BA09 CA03 4J002 BB051 BB071 BB081 BB082 BB091 BB111 BB171 BB181 BD052 BD102 BF022 BG102 FA027 GH02 FA027 FA027 DJ027 DJ027 DE0 DE077 DE007 DE077 EN0070 AA02P AA03P AA04P AA06P AA07P AA16P AE03Q AE04Q AJ09R AK32R AL03Q AL39Q AM15Q AM17Q AM19Q CA05 JA01

Claims (22)

[Claims] 1. An aqueous dispersion containing the following polyolefin resin, wherein the polyolefin resin has a number average particle size of 1 μm or less, and the aqueous dispersion contains substantially no non-volatile hydration aid. A polyolefin resin aqueous dispersion characterized by: Polyolefin resin: (A1) unsaturated carboxylic acid or anhydride thereof, (A2) ethylene hydrocarbon, (A3) at least one compound represented by any of the following formulas (I) to (IV) A polyolefin resin which is a copolymer having the following formulas (1) and (2) in which the mass ratio of each of the constituent components (A1) to (A3) is satisfied. 0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1) (A2) / (A3) = 55/45 to 99/1 (2) [Chemical formula 1] 2. The polyolefin resin aqueous dispersion according to claim 1, wherein the melt flow rate of the polyolefin resin at 190 ° C. under a load of 2160 g is 0.01 to 500 g / 10 minutes. 3. The polyolefin resin aqueous dispersion according to claim 2, 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 minutes. 4. An unsaturated carboxylic acid or its anhydride (A
The resin aqueous dispersion composition according to claim 1, wherein the component 1) is at least one selected from maleic anhydride, acrylic acid and methacrylic acid. 5. The polyolefin resin aqueous dispersion according to claim 1, wherein the compound (A3) is a compound represented by the formula (I). 6. The polyolefin 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. Aqueous resin dispersion. 7. The 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. 8. The organic solvent has at least one atom having a Pauling electronegativity of 3.0 or more in the molecule,
The aqueous dispersion of polyolefin resin according to claim 7, which is an organic solvent having a boiling point of 30 to 250 ° C. 9. The aqueous dispersion further contains a basic compound, and the content of the basic compound is 0.5 to 3.0 times equivalent mole based on the number of moles of the carboxyl group in the polyolefin resin. The polyolefin resin aqueous dispersion according to claim 1. 10. The polyolefin resin aqueous dispersion according to claim 9, wherein the basic compound is an organic amine compound having a boiling point of 30 to 250 ° C. 11. A polyolefin resin aqueous dispersion is coated at 25 ° C. with a film thickness of 2 μm (after drying) on a film having a haze (cloudiness value) of 2.0 to 5.0 (%) at 25 ° C., and then at 25 ° C. The aqueous haze of the polyolefin resin according to claim 1, characterized in that the haze of the entire coated film obtained by drying with 1. is 10.0 (%) or less. 12. A polyolefin resin aqueous dispersion is coated at 5 ° C. on a film having a haze (cloudiness value) of 2.0 to 5.0 (%) at a film thickness of 2 μm (after drying), and then at 5 ° C. The aqueous haze of the polyolefin resin according to claim 1, characterized in that the haze of the entire coated film obtained by drying with 1. is 10.0 (%) or less. 13. An aqueous dispersion which is a mixture of the aqueous dispersion of the polyolefin resin according to claim 1 and an aqueous dispersion of another polymer. 14. The aqueous dispersion according to claim 1, which further contains a metal ion. 15. The aqueous dispersion according to claim 1, further comprising inorganic particles having an average particle size of 0.005 to 10 μm. 16. The aqueous dispersion according to claim 1, further comprising 0.01 to 100 parts by mass of a crosslinking agent based on 100 parts by mass of the resin in the aqueous dispersion. 17. A coating agent composition containing the aqueous dispersion according to claim 1. 18. A coating composition containing the aqueous dispersion according to claim 1. 19. An adhesive composition containing the aqueous dispersion according to claim 1. 20. The following polyolefin resin, basic compound, and water are used as raw materials, and these are used in a closed container at 80 to 200
A method for producing a polyolefin resin aqueous dispersion, which comprises heating and stirring at a temperature of ° C. Polyolefin resin: (A1) unsaturated carboxylic acid or anhydride thereof, (A2) ethylene hydrocarbon, (A3) at least one compound represented by any of the above formulas (I) to (IV) A polyolefin resin which is a copolymer having the following formulas (1) and (2) in which the mass ratio of each of the constituent components (A1) to (A3) is satisfied. 0.01 ≦ (A1) / {(A1) + (A2) + (A3)} × 100 <5 (1) (A2) / (A3) = 55/45 to 99/1 (2) 21. The method for producing an aqueous dispersion of a polyolefin resin according to claim 20, wherein an organic solvent is further used as a raw material. 22. A method for producing an aqueous dispersion, which comprises obtaining the polyolefin resin aqueous dispersion by the method according to claim 21 and further performing a solvent removal treatment to reduce the organic solvent content of the aqueous dispersion. Method.