JP2008156397A - Aqueous dispersion, method for producing the same and coated material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous dispersion having excellent adhesiveness to a thermoplastic resin, particularly a styrenic resin and forming a film having high water resistance and moisture resistance without using a chlorine-containing resin. <P>SOLUTION: The aqueous dispersion comprises an ethylene-vinyl acetate copolymer (A) having 63-77 mass% ethylene content and 20,000-100,000 mass-average molecular weight, an acid-modified polyolefin (B) having 1,000-10,000 mass-average molecular weight, an anionic emulsifier (C) and water. The content of the acid-modified polyolefin (B) is 5-20 pts.mass based on 100 pts.mass of the ethylene-vinyl acetate copolymer (A) and the content of the anionic emulsifier (C) is 3-20 pts.mass based on 100 pts.mass of the ethylene-vinyl acetate copolymer (A). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an aqueous dispersion used as a primer for a thermoplastic resin, a binder, an adhesive, and the like, and a method for producing the same. The present invention also relates to a coated product obtained by coating an aqueous dispersion on a substrate.

Plastics such as thermoplastic resins are used in various members such as automobiles, home appliances, and building materials, and are expected to continue to increase in the future. Especially in automobiles, plastics have recently been used not only for interior parts but also for electronic parts, fuel systems, etc. as well as functional parts in the engine room.
In general, a plastic molded product is used after being painted in order to enhance design properties. For coating, solvent-based paints have been widely used because of their excellent drying performance, coating film appearance, adhesion, etc. In recent years, water-based paints have been used due to environmental pollution of various solvents and their harmfulness to the human body. There is a need for alternatives.
However, although the water-based paint has little influence on the environment, it has low adhesion to the thermoplastic resin, and the resulting film has low water resistance and moisture resistance. This was particularly remarkable when the thermoplastic resin contained a styrene resin.
Therefore, an aqueous coating composition containing chlorinated polyolefin has been proposed as an aqueous coating having high adhesion to a thermoplastic resin (see Patent Document 1).
Japanese Patent No. 3738876

However, the water-based coating composition described in Patent Document 1 also has insufficient adhesion to styrene resins such as ABS resin, and the resulting film has insufficient water resistance and moisture resistance.
Moreover, the water-based coating composition described in Patent Document 1 has a chlorine-containing resin called chlorinated polyolefin as a main component, and has a problem in terms of generation of chlorine gas and recycling during waste incineration. Therefore, there has been a demand for an aqueous coating composition that does not contain a chlorine-containing resin.
An object of the present invention is to provide an aqueous dispersion which does not use a chlorine-containing resin, has excellent adhesion to thermoplastic resins, particularly styrene resins, and can form a film having high water resistance and moisture resistance. . Moreover, it is providing the manufacturing method of the aqueous dispersion which can manufacture such an aqueous dispersion easily. Furthermore, the objective of this invention is providing the coated material which has a film | membrane excellent in water resistance and moisture resistance.

The present invention includes the following configurations.
[1] An ethylene vinyl acetate copolymer (A) having an ethylene content of 63 to 77% by mass and a mass average molecular weight of 20,000 to 100,000, and a mass average molecular weight of 1,000 to 10,000. An acid-modified polyolefin (B), an anionic emulsifier (C), and water;
The content of the acid-modified polyolefin (B) is 5 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A),
Content of anionic emulsifier (C) is 3-20 mass parts with respect to 100 mass parts of ethylene vinyl acetate copolymers (A), The aqueous dispersion liquid characterized by the above-mentioned.
[2] The aqueous dispersion according to [1], wherein the acid-modified polyolefin (B) is acid-modified polyethylene.
[3] A step of melt-kneading the ethylene vinyl acetate copolymer (A), the acid-modified polyolefin (B), and the anionic emulsifier (C) to prepare a melt-kneaded product; Adding 2 to 15 parts by mass with respect to 100 parts by mass of the vinyl copolymer, and further melt-kneading,
An ethylene vinyl acetate copolymer (A) having an ethylene content of 63 to 77% by mass and a mass average molecular weight of 20,000 to 100,000 is used, and the acid-modified polyolefin (B) has a mass average molecular weight. Use 1,000 to 10,000,
The addition amount of the acid-modified polyolefin (B) is 5 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A),
The method for producing an aqueous dispersion, wherein the amount of the anionic emulsifier (C) added is 3 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A).
[4] The method for producing an aqueous dispersion according to [3], wherein an alkaline aqueous solution is added to the melt-kneaded material instead of water.
[5] The method for producing an aqueous dispersion according to [4], wherein an organic acid is used instead of the anionic emulsifier (C).
[6] A group comprising the thermoplastic dispersion (F) containing the rubber-containing aromatic vinyl-based graft copolymer (D) and the hard polymer (E) as the aqueous dispersion according to [1] or [2]. A coated product characterized by being coated on a material.
[7] The thermoplastic resin (F) contains 50 to 70 parts by mass of an aromatic vinyl monomer unit with respect to 100 parts by mass of the thermoplastic resin (F). The coated product described.
[8] The total amount of the rubber-containing aromatic vinyl-based graft copolymer (D) and the hard polymer (E) in the thermoplastic resin (F) is 40 to 100 parts by mass [6 ] Or the coated material according to [7].

The aqueous dispersion of the present invention does not use a chlorine-containing resin, and can form a film having excellent adhesion to thermoplastic resins, particularly styrene resins, and high water resistance and moisture resistance.
According to the method for producing an aqueous dispersion of the present invention, the above-described aqueous dispersion can be easily produced.
The coated product of the present invention has a film excellent in water resistance and moisture resistance.

(Aqueous dispersion)
The aqueous dispersion of the present invention contains an ethylene vinyl acetate copolymer (A), an acid-modified polyolefin (B), an anionic emulsifier (C), and water.

<Ethylene vinyl acetate copolymer (A)>
The ethylene vinyl acetate copolymer (A) is a copolymer obtained by copolymerizing ethylene and vinyl acetate. However, some vinyl acetate units may be saponified.
The ethylene vinyl acetate copolymer (A) has an ethylene content of 63 to 77 mass%, preferably 70 to 74 mass%. When the ethylene content of the ethylene-vinyl acetate copolymer (A) exceeds 77% by mass, the adhesion to the thermoplastic resin is lowered, and when it is less than 63% by mass, the water resistance is lowered.
The ethylene vinyl acetate copolymer (A) has a mass average molecular weight of 20,000 to 100,000, preferably 50,000 to 70,000. If the mass average molecular weight of the ethylene vinyl acetate copolymer (A) exceeds 100,000, the adhesion to the thermoplastic resin tends to be low, and if it is less than 20,000, a practical film cannot be formed. is there.
The X-ray crystallinity of the ethylene-vinyl acetate copolymer (A) is preferably 25% or less (may be 0%). When the X-ray crystallinity of the ethylene-vinyl acetate copolymer (A) exceeds 25%, the film obtained from the aqueous dispersion tends to crack and the adhesion tends to be lowered.

<Acid-modified polyolefin (B)>
The acid-modified polyolefin (B) is obtained by acid-modifying a polyolefin with an unsaturated carboxylic acid. The unsaturated carboxylic acid may form a salt.
Examples of the polyolefin constituting the acid-modified polyolefin (B) include polyethylene, polypropylene, and the like. Specifically, an ethylene homopolymer, a propylene homopolymer, a copolymer of ethylene and propylene, ethylene or propylene And other α-olefin copolymers, copolymers of ethylene or propylene and vinyl compounds, and the like.
When the polyolefin is a copolymer of ethylene or propylene and another α-olefin, the other α-olefin may be an α-olefin having 4 to 18 carbon atoms such as 1-butene, isobutene, 1-pentene, 4 -Methyl-1-pentene, 1-hexene, 1-octene, 1-decene, 1-dodecene and the like.
As the unsaturated carboxylic acid, an unsaturated dicarboxylic acid is preferable.
Acid-modified polyolefin may be used individually by 1 type, and may use 2 or more types together.
Among the acid-modified polyolefins, those having high compatibility with the ethylene vinyl acetate copolymer (A) are effective in reducing the particle size of the aqueous dispersion, and therefore, the acid-modified polyethylene obtained by acid-modifying the ethylene homopolymer. Is preferred.

  The mass average molecular weight of the acid-modified polyolefin (B) is 1,000 to 10,000, and preferably 2,000 to 4,000. Even if the mass average molecular weight of the acid-modified polyolefin is less than 1,000 or more than 10,000, the particle diameter of the aqueous dispersion increases and the adhesion decreases.

  The amount of the acid-modified polyolefin (B) is 5 to 20 parts by mass and preferably 7 to 18 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A). When the amount of the acid-modified polyolefin (B) is less than 5 parts by mass or exceeds 20 parts by mass, a stable emulsion cannot be obtained and the amount of aggregates increases.

<Anionic emulsifier (C)>
The anionic emulsifier (C) in the present invention is an alkali metal salt of an organic acid (for example, sodium salt, potassium salt, etc.).
Examples of the organic acid constituting the anionic emulsifier (C) include primary higher fatty acids, secondary higher fatty acids, primary higher alcohol sulfates, secondary higher alcohol sulfates, and primary higher alkyl sulfones. Acid, secondary higher alkyl sulfonic acid, higher alkyl disulfonic acid, sulfonated higher fatty acid, higher fatty acid sulfate ester, higher fatty acid ester sulfonic acid, higher alcohol ether sulfate sulfonic acid, higher alcohol ether sulfonic acid, higher fatty acid amide Examples thereof include alkylolated sulfuric acid ester, alkylbenzene sulfonic acid, alkylphenol sulfonic acid, alkylnaphthalene sulfonic acid, and alkylbezoimidazole sulfonic acid.
Among these organic acids, particularly preferred are higher fatty acids, particularly saturated or unsaturated higher fatty acid salts having 10 to 20 carbon atoms, particularly alkali metal salts. Specifically, capric acid, Unsaturated fatty acids such as undecanoic acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, arachidic acid, etc. Mention may be made of fatty acids or mixtures thereof.
An anionic emulsifier (C) may be used individually by 1 type, and may use 2 or more types together.
A commercially available thing may be used as an anionic emulsifier (C), and the alkali metal salt of the organic acid obtained by neutralizing an organic acid may be used.

  The content of the anionic emulsifier (C) in the aqueous dispersion is in the range of 3 to 20 parts by mass and 5 to 15 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A). preferable. Even if the content of the anionic emulsifier (C) is less than 3 parts by mass or more than 20 parts by mass, a stable emulsion cannot be obtained and the amount of aggregates increases.

<Other ingredients>
The aqueous dispersion of the present invention can be used in various auxiliary materials that can be used in ordinary aqueous dispersions as necessary, for example, emulsifiers other than anionic emulsifiers, dispersants, stabilizers, wetting agents, foaming agents. , Coagulant, gelling agent, antioxidant, UV absorber, hydrochloric acid absorber, pigment, dye, nucleating agent, antiblocking agent, slip agent, antistatic agent, flame retardant, plasticizer, filler, colorant, A flavoring agent, an anti-tacking agent, a release agent and the like may be included.
In addition, the aqueous dispersion of the present invention may contain an aqueous resin selected from the group of an aqueous acrylic resin, an aqueous urethane resin, and an aqueous olefin resin as necessary. These aqueous resins can be produced by a known emulsification technique.

<Properties of aqueous dispersion>
In the aqueous dispersion of the present invention, resin solids derived from the ethylene vinyl acetate copolymer (A) and the acid-modified polyolefin (B) are emulsified and dispersed in water.
The average particle size of the resin solid content in the aqueous dispersion is preferably 0.01 to 5 μm, more preferably 0.1 to 1 μm, and particularly preferably 0.15 to 0.4 μm. An aqueous dispersion having an average particle size of the resin solid content of less than 0.01 μm may not be easily produced, and the adhesion to the thermoplastic resin tends to decrease. If the average particle size of the resin solids exceeds 5 μm, the storage stability of the aqueous dispersion tends to be reduced.
The aqueous dispersion of the present invention preferably has a solid content concentration of 25 to 65% by mass. When the solid content concentration is less than 25% by mass, the adhesiveness to the thermoplastic resin tends to be lowered and becomes impractical, and when the solid content concentration exceeds 65% by mass, the storage stability of the aqueous dispersion decreases. Tend to.

As a result of investigations by the present inventors, the aqueous dispersion containing the specific ethylene vinyl acetate copolymer and acid-modified polyolefin described above is excellent in adhesion to thermoplastic resins, particularly styrene resins such as ABS resins. There was found. Moreover, according to the aqueous dispersion mentioned above, it turned out that the film | membrane with high water resistance and moisture resistance can be formed.
Further, since the above-mentioned aqueous dispersion does not use a chlorine-containing resin, problems are unlikely to occur in terms of generation of chlorine gas and recycling during waste incineration.
Such an aqueous dispersion is suitable for applications such as a primer, a binder, and an adhesive used when adhering or coating a thermoplastic resin, in particular, a styrene resin.

(Method for producing aqueous dispersion)
An example of the method for producing the aqueous dispersion of the present invention will be described.
In this example, the aqueous dispersion is prepared by melt-kneading the ethylene-vinyl acetate copolymer (A), the acid-modified polyolefin (B), and the anionic emulsifier (C) by melt-kneading means. And a step of adding water to the melt-kneaded product, further melt-kneading and phase-inverting (hereinafter referred to as phase-inversion step). The melt-kneading step and the phase inversion step may be performed sequentially or simultaneously.

  Examples of the melt-kneading means used in the melt-kneading process include a kneader, a Banbury mixer, and a multi-screw extruder.

The amount of the acid-modified polyolefin (B) added in the melt-kneading step is preferably 5 to 20 parts by mass, and 7 to 18 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A). More preferred. When the addition amount of the acid-modified polyolefin (B) is less than 5 parts by mass or exceeds 20 parts by mass, a stable emulsion cannot be obtained and the amount of aggregates increases.
The addition amount of the anionic emulsifier (C) is preferably 3 to 20 parts by mass and more preferably 4 to 13 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A). Even if the addition amount of the anionic emulsifier (C) is less than 3 parts by mass or more than 20 parts by mass, a stable emulsion cannot be obtained and the amount of aggregates increases.

As will be described later, in the phase inversion step, an organic acid may be used instead of the anionic emulsifier (C) when an aqueous alkali solution in which an alkaline substance is dissolved in water is added to the melt-kneaded product. This is because the organic acid forms an anionic emulsifier (C) with an alkaline substance.
As the organic acid, the same organic acid as that constituting the anionic emulsifier (C) is used.

  In the melt-kneading step, heating is preferably performed simultaneously with the melt-kneading, and the heating temperature is preferably 140 to 240 ° C. Even if the heating temperature is less than 140 ° C. or exceeds 240 ° C., it tends to be difficult to obtain an aqueous dispersion.

In the phase inversion step, it is preferable to add an alkaline substance simultaneously with water. Alkaline substances include substances that act as bases in water, such as alkali metals, alkaline earth metals, ammonia, and amines, alkali metal oxides, hydroxides, weak bases, hydrides, alkaline earth metal oxides And substances that act as bases in water, such as hydroxides, weak bases, hydrides, and alkoxides of these metals. These alkaline substances are used for saponification of an unneutralized acid-modified polyolefin and an organic acid that is neutralized to become an anionic emulsifier.
As for the addition amount of an alkaline substance, 0.4-8 mass parts is preferable with respect to an ethylene vinyl acetate copolymer (A).
When an alkaline substance is added simultaneously with water, an alkaline aqueous solution in which an alkaline substance is dissolved in water may be added instead of water. When an alkaline aqueous solution is added, a more stable aqueous dispersion can be produced.

The amount of water added in the phase inversion step is 2 to 15 parts by mass and preferably 4 to 13 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A). When the amount of water added is less than 2 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A), it is difficult to reduce the particle size of the aqueous dispersion, and the water resistance and moisture resistance of the film are reduced. Even if it exceeds 20 parts by mass, it is difficult to reduce the particle size of the aqueous dispersion, and the water resistance and moisture resistance of the film are lowered.
When adding alkaline aqueous solution instead of water, the addition amount of alkaline aqueous solution is 2-15 mass parts with respect to 100 mass parts of ethylene vinyl acetate copolymer (A).

  Even during the phase inversion step, it is preferable to heat at 140 to 240 ° C. as in the melt-kneading step. When heated, the obtained aqueous dispersion is preferably cooled to about room temperature by natural cooling or forced cooling.

  According to the production method having the melt-kneading step and the phase inversion step described above, an aqueous dispersion in which resin solids derived from the ethylene vinyl acetate copolymer (A) and the acid-modified polyolefin (B) are emulsified and dispersed in water is obtained. Easy to manufacture. Moreover, according to this production method, an aqueous dispersion having excellent stability can be obtained.

(Coated product)
In the coated product of the present invention, the above-described aqueous dispersion is applied to a base material composed of a thermoplastic resin (F) containing a rubber-containing aromatic vinyl-based graft copolymer (D) and a hard polymer (E). It is made by coating.

  After coating the aqueous dispersion on the substrate, it is preferable to dry at a drying temperature higher than the melting point of the ethylene vinyl acetate copolymer (A). If it is dried at a temperature higher than the melting point of the ethylene-vinyl acetate copolymer (A), the film formability is improved and the adhesion is further increased.

<Base material>
[Rubber-containing aromatic vinyl-based graft copolymer (D)]
The rubber-containing aromatic vinyl-based graft copolymer (D) is obtained by graft-polymerizing a rubbery polymer with a raw material monomer containing an aromatic vinyl-based monomer.
Examples of rubber polymers include conjugated diene polymers (eg, polybutadiene, copolymers of butadiene and vinyl monomers other than butadiene), acrylic ester polymers (eg, acrylate polymer, acrylic polymer). A copolymer of an acid ester and a vinyl monomer other than an acrylate ester, etc.), ethylene-propylene or butene, preferably a propylene-nonconjugated diene copolymer, a polyorganosiloxane polymer, and the like. Here, as the acrylic ester of the acrylic ester polymer, methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, isobutyl acrylate, pentyl acrylate, isoamyl acrylate, n-hexyl acrylate, 2-methylpentyl acrylate, 2-ethylhexyl Examples include acrylate and n-octyl acrylate. Dienes contained in the ethylene-propylene-nonconjugated diene copolymer include dicyclopentadiene, 1,4-hexadiene, 1,4-heptadiene, 1,5-cyclooctadiene, 6-methyl-1,5- Heptadiene, 11-ethyl-1,11-tridecadiene, 5-methylene-2-norbornene and the like can be mentioned.
As the rubbery polymer, one of these can be used alone or as a composite rubber of two or more.

Examples of the aromatic vinyl monomer contained in the raw material monomer that is graft-polymerized on the rubber polymer include styrene, α-methylstyrene, p-methylstyrene, and bromostyrene. Among these, styrene and α-methylstyrene are preferable for improving the adhesion to styrene resins.
In addition, the raw material monomer may contain a vinyl cyanide monomer, a (meth) acrylic acid ester, a maleimide compound, an unsaturated carboxylic acid, and the like as necessary.
Examples of the vinyl cyanide monomer include acrylonitrile and methacrylonitrile, and acrylonitrile is particularly preferable.
Examples of (meth) acrylic acid esters include methacrylic acid esters or acrylic acid esters such as methyl methacrylate and methyl acrylate.
Examples of the maleimide compound include N-phenylmaleimide, N-cyclohexylmaleimide and the like.
Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, fumaric acid and the like.
These can be used individually by 1 type or in mixture of 2 or more types, respectively.

[Hard polymer (E)]
The hard polymer (E) has a glass transition temperature of 40 ° C. or higher. Among the hard polymers (E), a copolymer of an aromatic vinyl monomer and a vinyl cyanide monomer is preferable in order to increase adhesion to the ABS resin. Examples of the aromatic vinyl monomer and the vinyl cyanide monomer include those described above.
The copolymer is obtained by further copolymerizing another unsaturated monomer copolymerizable with an aromatic vinyl monomer and a vinyl cyanide monomer and another monomer. Also good. Examples of other monomers include the above-mentioned (meth) acrylic acid esters, maleimide compounds, unsaturated carboxylic acids, and the like.

  The thermoplastic resin (F) may contain other thermoplastic resins. As another thermoplastic resin, a polycarbonate excellent in compatibility with the rubber-containing aromatic vinyl graft polymer (F) and the hard polymer (E) is preferable.

[Composition of thermoplastic resin (F)]
The total amount of the rubber-containing aromatic vinyl graft copolymer (D) and the hard polymer (E) in the thermoplastic resin (F) is preferably 40 to 100 parts by mass. When the total amount of the rubber-containing aromatic vinyl-based graft copolymer (D) and the hard polymer (E) in the thermoplastic resin (F) is less than 40 parts by mass, the film obtained from the aqueous dispersion is adhered. The water resistance and moisture resistance may be low.
In the thermoplastic resin (F), the aromatic vinyl monomer unit is preferably contained in an amount of 50 to 70 parts by mass, more preferably 55 to 65 parts by mass with respect to 100 parts by mass of the thermoplastic resin. preferable. When the aromatic vinyl monomer unit is less than 50 parts by mass, the adhesion of the film obtained from the aqueous dispersion is low, and the water resistance and moisture resistance may be low. The adhesion of the film obtained from the dispersion is reduced.

[shape]
The shape of the substrate is not particularly limited, and may be, for example, a sheet shape or a three-dimensional shape.

  Since the above-mentioned coated product is obtained by coating the aqueous dispersion on a substrate, it has a film having excellent water resistance and moisture resistance on the substrate.

  EXAMPLES Hereinafter, although a manufacture example, an Example, and a comparative example are given and this invention is demonstrated further more concretely, this invention is not limited to a following example. In the following description, “part” means “part by mass”, and “%” means “% by mass”.

In the following example:
-The ethylene content of the ethylene vinyl acetate copolymer was measured according to JIS K7192.
-The mass average molecular weight was measured by the GPC method. Numerical values are in terms of polystyrene.
-Melting | fusing point of ethylene vinyl acetate copolymer was measured based on JISK7121.
The X-ray crystallinity of the ethylene vinyl acetate copolymer was measured with an X-ray diffractometer (LabX XRD-6100, manufactured by Shimadzu Corporation).
-The average particle size of the resin solid content in the aqueous dispersion was measured by Microtrac UPA (Mountech Co. Ltd).

(Production Example 1): Production of aqueous dispersion (X-1) Ethylene vinyl acetate having an ethylene content of 72%, a mass average molecular weight of 61,000, a melting point of 62 ° C, and an X-ray crystallinity of 15%. 100 parts of polymer ("Evaflex EV210" manufactured by Mitsui DuPont Polychemical Co., Ltd.) and maleic anhydride-modified polyethylene (Mitsui Chemicals Co., Ltd. "Mitsui Chemicals Co., Ltd.") having a weight average molecular weight of 2,700 which is an acid-modified polyolefin. "High Wax 2203A", referred to as "Acid-modified Polyethylene A" in the table.) 7 parts and 8 parts of potassium oleate, an anionic emulsifier, were mixed.
Subsequently, the obtained mixture was supplied from a hopper of a twin screw extruder (“PCM-30 type” manufactured by Ikekai Tekko Co., Ltd., L / D = 40) at a rate of 4 kg / hour, and melt kneaded. Further, a 9% aqueous potassium hydroxide solution was melted and kneaded at a heating temperature of 160 ° C. while continuously supplying at 240 g / hour to obtain a melt. Subsequently, the melt was continuously supplied to a cooling device attached to the tip of the twin screw extruder and cooled to 90 ° C.
Then, the solid obtained by cooling is poured into warm water at 80 ° C. and continuously dispersed, and an aqueous dispersion (X-1) having an average particle size of resin solid content of 0.21 μm and a solid content concentration of 40%. )

(Production Example 2): Production of Aqueous Dispersion (X-2) As acid-modified polyolefin, maleic anhydride-modified polypropylene having a mass average molecular weight of 3,000 (“Lycocene PP MA 6252” manufactured by Clariant Japan Co., Ltd.) 7 The aqueous dispersion (X-2) having an average particle size of resin solid content of 1.21 μm and a solid content concentration of 40% was obtained in the same manner as in Production Example 1 except that the parts were used.

(Production Example 3): Production of aqueous dispersion (X-3) As acid-modified polyolefin, maleic anhydride-modified polyethylene having a mass average molecular weight of 1,500 ("Mitsui High Wax 1105A" manufactured by Mitsui Chemicals, Inc.), Table In this, it is expressed as “acid-modified polyethylene B”.) The same procedure as in Production Example 1 except that 7 parts were used was carried out, and the average particle size of the resin solid content was 0.53 μm and the solid content concentration was 40%. An aqueous dispersion (X-3) was obtained.

(Production Example 4): Production of aqueous dispersion (X-4) The same procedure as in Production Example 1 was conducted except that the aqueous potassium hydroxide solution was continuously supplied at 40 g / hour, and the average particle size of the resin solid content was An aqueous dispersion (X-4) having 1.36 μm and a solid content concentration of 40% was obtained.

(Production Example 5): Production of aqueous dispersion (X-5) The same procedure as in Production Example 1 was conducted except that the aqueous potassium hydroxide solution was continuously supplied at 800 g / hour, and the average particle size of the resin solid content was An aqueous dispersion (X-5) having 1.23 μm and a solid concentration of 40% was obtained.

(Production Example 6): Production of aqueous dispersion (X-6) The same procedure as in Production Example 1 was conducted except that 4 parts of potassium oleate was used as the anionic emulsifier, and the average particle size of the resin solids was 1. An aqueous dispersion (X-6) having a thickness of 38 μm and a solid content of 40% was obtained.

(Production Example 7): Production of aqueous dispersion (X-7) The same procedure as in Production Example 1 was conducted except that 18 parts of potassium oleate was used as the anionic emulsifier, and the average particle size of the resin solids was 0.00. An aqueous dispersion (X-7) having a particle size of 92 μm and a solid content of 40% was obtained.

(Production Example 8): Production of aqueous dispersion (X-8) Ethylene vinyl acetate having an ethylene content of 72%, a mass average molecular weight of 61,000, a melting point of 62 ° C, and an X-ray crystallinity of 15%. 100 parts of a polymer ("Evaflex EV210" manufactured by Mitsui DuPont Polychemical Co., Ltd.) and maleic anhydride-modified polyethylene (Mitsui Chemicals Co., Ltd., "Mitsui High") having a weight average molecular weight of 2,700 as an acid-modified polyolefin. 15 parts of wax 2203A ") was dissolved in 300 parts of toluene at 80 ° C., and 18 parts of potassium oleate was added as an anionic emulsifier to completely dissolve it to prepare a resin solution.
Subsequently, the resin solution was added to 288 parts of water at 80 ° C. and emulsified, and then stirred with a homomixer. Thereafter, toluene was removed under reduced pressure to obtain an aqueous dispersion (X-8) having an average particle size of resin solid content of 3.21 μm and a solid content concentration of 40%.

(Production Example 9): Production of aqueous dispersion (X-9) As an ethylene vinyl acetate copolymer, the ethylene content is 72%, the mass average molecular weight is 73,000, the melting point is 65 ° C., and the X-ray crystallinity is. The average particle size of the resin solid content was the same as in Production Example 1 except that 100 parts of 15% ethylene vinyl acetate copolymer (Mitsui DuPont Polychemical Co., Ltd. “Evaflex EV220”) was used. Was 0.29 μm, and an aqueous dispersion (X-9) having a solid concentration of 40% was obtained.

(Production Example 10): Production of aqueous dispersion (X-10) As an ethylene vinyl acetate copolymer, the ethylene content is 67%, the mass average molecular weight is 42,000, the melting point is 61 ° C, and the X-ray crystallinity is. The average particle diameter of the resin solid content was the same as in Production Example 1 except that 100 parts of 10% ethylene vinyl acetate copolymer (Mitsui / Dupont Polychemical Co., Ltd. “Evaflex V5772ET”) was used. Was 0.45 μm, and an aqueous dispersion (X-10) having a solid concentration of 40% was obtained.

(Production Example 11): Production of aqueous dispersion (X-11) As an ethylene vinyl acetate copolymer, the ethylene content is 75%, the mass average molecular weight is 56,000, the melting point is 66 ° C, and the X-ray crystallinity is. The average particle diameter of the resin solid content was the same as in Production Example 1 except that 100 parts of 18% ethylene vinyl acetate copolymer (Mitsui DuPont Polychemical Co., Ltd. “Evaflex EV310”) was used. Obtained an aqueous dispersion (X-11) having a solid content concentration of 0.25 μm and a solid content concentration of 40%.

Production Example 12 Production of Aqueous Dispersion (X-12) As an ethylene vinyl acetate copolymer, the ethylene content is 72%, the mass average molecular weight is 53,000, the melting point is 73 ° C., and the X-ray crystallinity is. The average particle diameter of the resin solid content was the same as in Production Example 1 except that 100 parts of ethylene vinyl acetate copolymer (“Evaflex EV210ET” manufactured by Mitsui DuPont Polychemical Co., Ltd.), which was 23%, was used. An aqueous dispersion (X-12) having a solid content concentration of 0.23 μm and 40% was obtained.

(Production Example 13): Aqueous dispersion (X-13)
As the acid-modified polyolefin, 7 parts of acid-modified polyethylene having a mass average molecular weight of 16,000 (“Yumex 2000” manufactured by Sanyo Chemical Industries, Ltd., referred to as “acid-modified polyethylene C” in the table) was used. Was carried out in the same manner as in Production Example 1 to obtain an aqueous dispersion (X-13) having an average particle size of resin solid content of 5.32 μm and a solid content concentration of 40%.

(Production Example 14): Production of aqueous dispersion (X-14) Production example except that 7 parts of montanic acid ("Licowax S" manufactured by Clariant Co., Ltd.) having a mass average molecular weight of 428 was used as the acid-modified polyolefin. In the same manner as in Example 1, an aqueous dispersion (X-14) having an average particle size of resin solid content of 1.80 μm and a solid content concentration of 40% was obtained.

(Production Example 15)
The procedure was the same as in Production Example 1 except that 3 parts of acid-modified polyethylene A was used as the acid-modified polyolefin. The solid thus taken out was poured into warm water at 80 ° C., but no aqueous dispersion was obtained.

(Production Example 16)
The procedure was the same as in Production Example 1 except that 25 parts of acid-modified polyethylene A was used as the acid-modified polyolefin. The solid thus taken out was poured into warm water at 80 ° C., but no aqueous dispersion was obtained.

(Production Example 17)
This was carried out in the same manner as in Production Example 1 except that 2 parts of potassium oleate was used as an anionic emulsifier, and the extracted solid was put into warm water at 80 ° C., but an aqueous dispersion was not obtained.

(Production Example 18)
This was carried out in the same manner as in Production Example 1 except that 25 parts of potassium oleate was used as an anionic emulsifier, and the extracted solid was put into warm water at 80 ° C., but an aqueous dispersion was not obtained.

(Production Example 19): Aqueous dispersion (X-15)
As an ethylene vinyl acetate copolymer, an ethylene vinyl acetate copolymer having an ethylene content of 81%, a mass average molecular weight of 56,000, a melting point of 75 ° C., and an X-ray crystallinity of 28% (Mitsui / Dupont Polychemical) Except for using 100 parts of “Evaflex EV410”) manufactured in the same manner as in Production Example 1, an aqueous dispersion having an average particle size of resin solid content of 0.19 μm and a solid content concentration of 40% ( X-15) was obtained.

(Production Example 20): Aqueous dispersion (X-16)
As an ethylene vinyl acetate copolymer, an ethylene vinyl acetate copolymer having an ethylene content of 59%, a mass average molecular weight of 90,000, a melting point of 40 ° C., and an X-ray crystallinity of 0% (Mitsui / Dupont Polychemical) (Evaflex EV40W • Y manufactured by Co., Ltd.) Except for using 100 parts, an aqueous dispersion having an average particle diameter of 0.72 μm and a solid content concentration of 40% was obtained in the same manner as in Production Example 1. (X-16) was obtained.

(Production Example 21): Aqueous dispersion (X-17)
As an ethylene vinyl acetate copolymer, an ethylene vinyl acetate copolymer having an ethylene content of 72%, a mass average molecular weight of 128,000, a melting point of 72 ° C., and an X-ray crystallinity of 15% (Mitsui / Dupont Polychemical) Except for using 100 parts of “Evaflex EV260”, manufactured in the same manner as in Production Example 1, an aqueous dispersion having an average particle size of resin solid content of 0.32 μm and a solid content concentration of 40% ( X-17) was obtained.

  Tables 1 and 2 summarize the formulation and average particle size of the aqueous dispersions of Production Examples 1 to 21.

(Example 1)
Apply the aqueous dispersion (X-1) to the following thermoplastic resins (Fa) to (Ff) (100 mm × 100 mm, 2 mm thickness) with a bar coater so that the dry film thickness is 20 μm, The coated material was obtained by drying at 70 ° C. for 30 minutes.
Thermoplastic resin (Fa): Rubber-containing aromatic vinyl-based graft copolymer (polybutadiene component 55%, acrylonitrile unit 10%, styrene component 35%) and a hard polymer (acrylonitrile) composed of acrylonitrile-styrene copolymer A composition containing 60 parts of 23% unit and 77% styrene unit).
Thermoplastic resin (Fb): a hard polymer (acrylonitrile) comprising 40 parts of rubber-containing aromatic vinyl graft copolymer (polybutadiene component 55%, acrylonitrile unit 17%, styrene component 28%) and acrylonitrile-styrene copolymer A composition containing 60 parts of 40% unit and 60% styrene unit).
Thermoplastic resin (Fc): Hard polymer (acrylonitrile) comprising 40 parts of rubber-containing aromatic vinyl graft copolymer (polybutadiene component 45%, acrylonitrile unit 5%, styrene component 50%) and acrylonitrile-styrene copolymer A composition containing 60 parts of 5% unit and 95% styrene unit).
Thermoplastic resin (Fd): 25 parts of rubber-containing aromatic vinyl graft copolymer (polybutadiene component 55%, acrylonitrile unit 10%, styrene component 35%), acrylonitrile-styrene-α-methylstyrene-N-phenylmaleimide A composition containing 75 parts of a hard polymer comprising copolymer (acrylonitrile unit 29%, styrene unit 25%, α-methylstyrene unit 36%, N-phenylmaleimide unit 10%).
Thermoplastic resin (Fe): hard polymer (acrylonitrile) comprising 20 parts of rubber-containing aromatic vinyl-based graft copolymer (polybutadiene component 55%, acrylonitrile unit 10%, styrene component 35%) and acrylonitrile-styrene copolymer A composition containing 30 parts of 23% unit and 77% styrene unit and 50 parts of polycarbonate ("Iupilon S-2000R" manufactured by Mitsubishi Engineering Plastics Co., Ltd.).
Thermoplastic resin (Ff): polypropylene (“J715M” manufactured by Prime Polymer).

(Example 2)
Various coating materials were obtained in the same manner as in Example 1 except that the drying conditions after coating the aqueous dispersion (X-1) were 80 ° C. for 30 minutes.

(Example 3)
Various coating materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-2) was used as the aqueous dispersion.

Example 4
Various coating materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-3) was used as the aqueous dispersion.

(Example 5)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-4) was used as the aqueous dispersion.

(Example 6)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-5) was used as the aqueous dispersion.

(Example 7)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-6) was used as the aqueous dispersion.

(Example 8)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-7) was used as the aqueous dispersion.

Example 9
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-8) was used as the aqueous dispersion.

(Example 10)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-9) was used as the aqueous dispersion.

(Example 11)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-10) was used as the aqueous dispersion.

(Example 12)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-11) was used as the aqueous dispersion.

(Example 13)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-12) was used as the aqueous dispersion.

(Example 14)
The same as Example 1 except that the aqueous dispersion (X-1) was changed to the aqueous dispersion (X-12) and the drying conditions after coating the aqueous dispersion (X-12) were 80 ° C. for 30 minutes. To obtain various coated products.

(Comparative Example 1)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-13) was used as the aqueous dispersion.

(Comparative Example 2)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-14) was used as the aqueous dispersion.

(Comparative Example 3)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-15) was used as the aqueous dispersion.

(Comparative Example 4)
The same as Example 1 except that the aqueous dispersion (X-1) was changed to the aqueous dispersion (X-15) and the drying conditions after coating the aqueous dispersion (X-15) were 80 ° C. for 30 minutes. To obtain various coated products.

(Comparative Example 5)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-16) was used as the aqueous dispersion.

(Comparative Example 6)
Various coated materials were obtained in the same manner as in Example 1 except that the aqueous dispersion (X-17) was used as the aqueous dispersion.

(Comparative Example 7)
The same as Example 1 except that the aqueous dispersion (X-1) was changed to the aqueous dispersion (X-17) and the drying conditions after coating the aqueous dispersion (X-17) were 80 ° C. for 30 minutes. To obtain various coated products.

(Comparative Example 8)
Various coated materials were obtained in the same manner as in Example 1 except that an aqueous chlorinated polyolefin dispersion (“Supercron E723” manufactured by Nippon Paper Chemicals Co., Ltd.) was used as the aqueous dispersion.

The resulting coated product was evaluated for adhesion, moisture resistance, and water resistance as follows. These results are shown in Tables 3-5.
・ Adhesion test After cutting the substrate surface with a cutter on the surface of the resulting coated film and forming 100 grids at intervals of 2 mm, and then sticking the adhesive tape on it, 180 degree direction Peeled off. Thereafter, the number of remaining grids was counted. The greater the remaining number, the better the adhesion.
-Humidity resistance test The obtained coated material was allowed to stand for 10 days under conditions of a relative humidity of 95% and 50 ° C in a programmed constant temperature and humidity chamber. Thereafter, the coating film was sufficiently dried and evaluated in the same manner as in the above adhesion test.
-Water resistance test The obtained coated material was immersed in water bath at 40 ° C for 10 days. Thereafter, the coating film was sufficiently dried and evaluated in the same manner as in the above adhesion test.

In the aqueous dispersions of Examples 1 to 14 containing specific amounts of specific ethylene vinyl acetate copolymer (A), acid-modified polyolefin (B) and anionic emulsifier (C), rubber-containing aromatic vinyl graft copolymer The adhesiveness to the thermoplastic resin containing the polymer (D) and the hard polymer was excellent. However, when the thermoplastic resin was polypropylene, the adhesion was low.
In addition, the aqueous dispersions of Examples 1 to 14 were excellent in water resistance and moisture resistance of the obtained films.

  The aqueous dispersion of Comparative Example 1 not containing the acid-modified polyolefin (B), the aqueous dispersion of Comparative Example 2 in which the mass average molecular weight of the acid-modified polyolefin exceeds the specific range, and the content of the anionic emulsifier (C) in the specific range The aqueous dispersion of Comparative Examples 3 and 4 and the ethylene vinyl acetate copolymer whose ethylene content is not in a specific range are specified. The aqueous dispersion of Comparative Examples 5 and 6 and the mass average molecular weight of the ethylene vinyl acetate copolymer are specified. The aqueous dispersion of Comparative Example 7 exceeding the range and the aqueous dispersion of Comparative Example 8 of the dispersion of chlorinated polyolefin had low adhesion to the thermoplastic resin, and the resulting film had low water resistance and moisture resistance. .

Claims (8)

Ethylene vinyl acetate copolymer (A) having an ethylene content of 63 to 77 mass% and a mass average molecular weight of 20,000 to 100,000, and an acid-modified polyolefin having a mass average molecular weight of 1,000 to 10,000 (B), an anionic emulsifier (C), and water,
The content of the acid-modified polyolefin (B) is 5 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A),
Content of anionic emulsifier (C) is 3-20 mass parts with respect to 100 mass parts of ethylene vinyl acetate copolymers (A), The aqueous dispersion liquid characterized by the above-mentioned.   The aqueous dispersion according to claim 1, wherein the acid-modified polyolefin (B) is acid-modified polyethylene. A step of melt-kneading the ethylene-vinyl acetate copolymer (A), the acid-modified polyolefin (B) and the anionic emulsifier (C) to prepare a melt-kneaded product; Adding 2 to 15 parts by mass with respect to 100 parts by mass of the coalescence and further melt-kneading,
An ethylene vinyl acetate copolymer (A) having an ethylene content of 63 to 77% by mass and a mass average molecular weight of 20,000 to 100,000 is used, and the acid-modified polyolefin (B) has a mass average molecular weight. Use 1,000 to 10,000,
The addition amount of the acid-modified polyolefin (B) is 5 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A),
The method for producing an aqueous dispersion, wherein the amount of the anionic emulsifier (C) added is 3 to 20 parts by mass with respect to 100 parts by mass of the ethylene vinyl acetate copolymer (A).   4. The method for producing an aqueous dispersion according to claim 3, wherein an alkaline aqueous solution is added to the melt-kneaded product instead of water.   The method for producing an aqueous dispersion according to claim 4, wherein an organic acid is used in place of the anionic emulsifier (C).   The aqueous dispersion according to claim 1 or 2 is coated on a substrate comprising a thermoplastic resin (F) containing a rubber-containing aromatic vinyl-based graft copolymer (D) and a hard polymer (E). A coated product characterized by being made.   The coating material according to claim 6, wherein the thermoplastic resin (F) contains 50 to 70 parts by mass of an aromatic vinyl monomer unit with respect to 100 parts by mass of the thermoplastic resin (F). Artifacts.   The total amount of the rubber-containing aromatic vinyl-based graft copolymer (D) and the hard polymer (E) in the thermoplastic resin (F) is 40 to 100 parts by mass. The coated product described in 1.