JPH03192172A - Coating composition and coating film - Google Patents

Abstract

PURPOSE:To prepare a coating compsn. which can be directly applied to a film and gives a coating film excellent in the transparency and resistance to steam whitening by mixing an aq. soln. of an acrylic resin or an aq. dispersion of fine particles of the acrylic resin with an aq. dispersion of an acrylic resin contg. a conductive copolymer. CONSTITUTION:The title compsn. is prepd. by mixing: 5-50wt.% (solid basis) compsn. comprising an aq. soln. of a copolymer or an aq. dispersion of particles (with diameters of 0.1mum or lower) of the copolymer which comprises an alpha,beta- unsatd. carboxylic acid, an alkyl (meth)acrylate, and a vinylic monomer as needed and has an acid value of 10-200 and in which at least 30% of carboxyl groups are converted into a salt; with 95-50wt.% (solid basis) aq. dispersion comprising 0.5-20 pts.wt. monomer mixture consisting of a conductive vinylic monomer having a sulfonic acid (salt) group and a vinylic monomer copolymerizable therewith and 100 pts.wt. monomer mixture consisting of an alpha,beta-unsatd. carboxylic acid, an alkyl (meth)acrylate, and a vinylic monomer.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an aqueous coating composition containing an acrylic resin as a main component, and more specifically relates to an aqueous coating composition containing an acrylic resin aqueous solution or a fine particle acrylic resin aqueous dispersion and a conductive coating composition. It is made by mixing an aqueous acrylic resin emulsion composition containing a polyester copolymer and is coated directly onto a plastic film (hereinafter referred to as film), etc., to achieve transparency, heat sealability, antistatic property, and water resistance. The present invention relates to an aqueous coating composition that provides an excellent coating film, and a film coated with the aqueous coating composition that has excellent transparency, heat sealability, antistatic properties, and water resistance.

(Prior art) With the spread of automatic packaging machines, there is an increasing demand for films that can be wrapped continuously and have both heat-sealability and antistatic properties. Suggestions have been made.

Furthermore, in recent years, the packaging speed of automatic packaging machines has been increased, and compared to before, the film is more likely to be charged due to static electricity caused by friction between the packaging machine and the film, and better antistatic properties are required. ing.

An effective method for producing a film with antistatic properties and easy heat-sealing properties suitable for high-speed packaging is to coat the film with a coating agent whose coating film has antistatic properties and easy heat-sealing properties. Japanese Patent Publication No. 54-9
By coating a film with an aqueous acrylic resin emulsion containing a conductive vinyl monomer having a sulfonate salt in the molecule, as disclosed in No. 5636, antistatic properties and easy heat-sealing properties suitable for high-speed packaging were achieved It is possible to produce a film having

There is also a method of applying a coating agent made of vinylidene chloride resin and an antistatic agent to a film that has been coated with acrylic resin, urethane resin, etc. in advance.

(Problems to be Solved by the Invention) An aqueous acrylic resin emulsion containing a conductive vinyl monomer, such as styrene sulfonate, which imparts excellent antistatic properties to the film, has a conductive vinyl monomer in the acrylic resin. Since the part consisting of is an electrolyte and is essentially hydrophilic, the coating film of the aqueous acrylic resin emulsion has poor water resistance, and there has been a problem that the applied film whitens with water or steam.

On the other hand, the method of applying a coating agent made by adding an antistatic agent to vinylidene chloride resin is difficult because vinylidene chloride resin has poor adhesion to films, especially polyolefin films with low surface energy. However, there are problems in that the manufacturing process is complicated, requires an undercoat, and is expensive.

(Objective of the Invention) The object of the present invention is to provide a water-based film that can be applied directly to a film, particularly a polyolefin film with low surface energy, to provide a coating film with excellent transparency, heat-sealability, antistatic properties, and water resistance. An object of the present invention is to provide a film coated with a coating composition and an aqueous coating composition, which has excellent transparency, heat-sealing properties, antistatic properties, and water resistance.

(Structure of the Invention) The present inventors have developed an aqueous coating composition in which a water-soluble acrylic resin or a fine particle aqueous dispersion of an acrylic resin is mixed into an acrylic resin aqueous emulsion containing a conductive vinyl monomer such as styrene sulfonate. It was discovered that the film can be coated directly without an undercoat, and that it is possible to produce a film with excellent transparency and water vapor whitening resistance that has antistatic properties suitable for high-speed packaging and easy heat-sealing properties. , completed the invention.

That is, the present invention provides: (1) (a) an α,β-unsaturated carboxylic acid having at least one carboxyl group; and (b) an alkyl (meth)acrylic acid ester (the alkyl group having 1 to 4 carbon atoms); a copolymer consisting of at least one type of (having an atom) and, if necessary, (c) a vinyl monomer capable of radical copolymerization with the above (a) e (b), the copolymer comprising: Acid value is lO~
200 and in which at least 30 groups of carboxyl groups contained in the polymer form a salt, and an aqueous composition in which a copolymer having a particle size of 0.1 micron or less is dissolved or dispersed in an aqueous medium. , (TI) as the A component (d) sulfone Fl! or at least one kind of conductive vinyl monomer having a salt thereof in the molecule 100-25 (e) A monomer mixture consisting of the above (d) and a vinyl monomer radically copolymerizable with 0-75 .5 to 20 parts by weight as component B (f) α, β having at least one carboxyl group
- at least one unsaturated carboxylic acid (0 to 10% by weight) at least one (meth)acrylic acid alkyl ester, the alkyl group of which has from 1 to 12 carbon atoms;
Species 10 to 98 parts by weight (h) The above (f) p (g) and 100 parts by weight of a monomer mixture consisting of a radical copolymerizable vinyl monomer θ to 80 parts by weight, and a copolymer consisting of component A. An aqueous emulsion composition containing substantially particles of a copolymer obtained by polymerizing component B in an aqueous medium in the presence of an aqueous emulsion composition having a solid content weight ratio of (1) / (II) = 5 to
The present invention provides a coating composition formed by mixing the composition in a ratio of 50/95 to 50, and a plastic film coated with the coating composition.

[Aqueous composition (i)]

(-) used in the aqueous composition (1) constituting the present invention
Examples of α,β-unsaturated carzenic acid having at least one carboxyl group (hereinafter referred to as monomer (a)) include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, and citraconic acid. There are acids, maleic anhydride, etc. Further, when an α,β-unsaturated carboxylic acid having two or more carboxyl groups is used as the monomer (a), a half ester thereof may be used.

Next, (b) (meth)acrylic acid alkyl ester whose alkyl group has 1 to 4 carbon atoms (hereinafter abbreviated as monomer (b)) means methyl (meth)acrylate,
They are ethyl (meth)acrylate, propyl (meth)acrylate, and butyl (meth)acrylate.

A vinyl monomer that can be radically copolymerized with the above monomer (a) and monomer (b) (hereinafter referred to as monomer (C))
Examples include hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, and (meth)acrylate.
Cyclohexyl acrylate, dicyclointinyl (meth)acrylate, benzyl (meth)acrylate, (meth)
Hydroxethyl acrylate, HyP (meth)acrylate
mouth pill, (meth)acrylic glycidyl, (meth)acrylamide, N-methylolacrylamide,
N-butyrolacrylamide, vinyl acetate, allyl acetate, styrene, vinyltoluene, vinyl chloride, (meth)
Examples include acrylonitrile.

If necessary, at least one of these monomers
You can use seeds.

The amount of nanatsuma to be used is such that the aqueous composition (1) constituting the present invention has an acid value of 10 to 200, preferably 25 to 100.

When the acid value is less than 10, it is extremely difficult to disperse particles of 0.1 micron or less even if the carboxylic group is converted into a salt with a ratio of 30 or more. It is difficult to fully express this. Furthermore, the coating film becomes more susceptible to attack by aliphatic organic solvents.

On the other hand, when the acid value exceeds 200, the water resistance of the coating film is poor, and furthermore, when the aqueous composition (1) constituting the present invention is obtained via emulsion polymerization, the stability during polymerization is poor. . When the acid value is in the range of 25 to 100, a copolymer with coating film flexibility suitable for use as a coating agent can be obtained.

The glass transition temperature (Tg) of the polymer in the aqueous composition (1)
) at a temperature of about 20 to about 120°C, preferably 40 to 10
It is 0°C.

When Tg is lower than 20°C, the coating film becomes sticky and causes blocking. On the other hand, when it is higher than 120℃,
The coating film is hard and has reduced flexibility, impairing its adhesion to the film, making it difficult to achieve practical heat-sealing strength. Tg
When the temperature is 40 to 100°C, 30% or more of the calagexyl groups contained in the polymer of the aqueous composition is converted into a salt, which facilitates dissolution or dispersion of particles of 0.1 micron or less in the aqueous medium. K to obtain the polymer of the aqueous composition of 0-(1) may be obtained by radical polymerization of the monomer (a), monomer (b), and monomer (C), and generally an anionic emulsifier and/or a nonionic emulsifier is used. It can be obtained by generally known emulsion polymerization using an emulsifier and a water-soluble radical polymerization initiator.

30 qb or more of carboxyl groups of the polymer thus obtained,
Preferably, the aqueous composition (1) constituting the present invention can be obtained by neutralizing with a base having an amount of 30 to 100 equivalents of the carboxyl group.

In addition, it is preferable to add a hydrophilic organic solvent such as cellosolves or alcohol during the neutralization reaction because the aqueous composition of (1) is more finely dispersed and becomes the following state, and the base used is Examples include ammonia, sodium hydroxide, potassium hydroxide, or organic amine compounds, but if the carboxyl group in the polymer remains as a salt even after the coating film is formed, the water resistance of the coating film will be poor. , volatile bases are preferable, and ammonia is more preferable from the point of view of odor.
It is also described in Publication No. 42.

[(Il) Aqueous emulsion composition 7 A of the aqueous emulsion composition (n) constituting the present invention
(d) Conductive vinyl monomer having sulfonic acid or its salt in the molecule (hereinafter referred to as monomer (d)) used as a component
)) include monomers represented by general formulas (1) to (2).

However, n　　0　+1 M=NH4 or an alkali metal such as Li, Na, etc. General formula (2) However, m=0.1 n=1-4 R1=H or CH.

M=NH4 or an alkali metal such as Ll, N&, K. Among these monomers, the sodium salt or ammonium salt of p-styrene sulfonic acid of the general formula (1) and sodium vinylbenzyl sulfonate are particularly preferred. It can be used suitably.

As the vinyl monomer (hereinafter abbreviated as monomer (a)) that can be radically copolymerized with the above monomer (a), monomers (a), monomers (b), and monomers (e) may be used alone or in combination. The above can be used in combination. The composition of monomer (e) is preferably the same as or close to the monomer composition of component B.

This increases the compatibility between the polymer of component A and the copolymer of component B, resulting in a coating composition with excellent transparency and good heat sealability.

Furthermore, by selecting a polymer with a high Tg as the monomer (a), blocking resistance is improved.

In component A, the ratio of monomer (d) to monomer (e) is 100 to 25 parts by weight for monomer (d) and 0 to 75 parts by weight for monomer (e).
d) 80 to 33 weight i%, seven months (e) 20 to 676
7 parts by weight. If the proportion of monomer (e) exceeds 75% by weight, the antistatic effect decreases, which is not preferable.

Further, it is preferable that the proportion of monomer (a) is 20 to 670 to 67 parts by weight, since a coating film having particularly good water resistance and blocking resistance can be obtained.

<Component B> In the aqueous emulsion composition of (II), (f) the α,β-unsaturated carboxylic acid having at least m carboxyl groups (hereinafter abbreviated as monomer (f)) used in component B is a monomer. The same things as (a) can be mentioned.

These monomers may be used alone or in combination of two or more.

Monomer (f) improves the stability of the aqueous emulsion composition (■) and has the effect of improving adhesion to the film, and its usage amount is 0-10 in component B.
Heavy:! If it exceeds 10% by weight or t%, the water resistance of the coating film of the coating composition of the present invention will decrease, which is not preferable.

The (meth)acrylic acid alkyl ester (the alkyl group has 1 to 12 carbon atoms) (hereinafter abbreviated as monomer (g)) used in component (2)) is (
meth)acrylic methyl, (meth)acrylic ethyl,
Examples include propyl (meth)acrylate, butyl (meth)acrylate, hexyl (meth)acrylate, octyl (meth)acrylate, and lauryl (meth)acrylate.

Next, the vinyl monomers capable of radical coexistence with the above monomers (f) and monomers (g) in (h) include stearyl (meth)acrylate, cyclohexyl (meth)acrylate, socycloanthynyl (meth)acrylate, (meta)
Benzyl acrylate, hydroxyethyl (meth)acrylate, hydroxyglobil (meth)acrylate, glycidyl (meth)acrylate, (meth)acrylamide, N
-butyrol (meth)acrylamide, vinyl acetate, allyl acetate, styrene, vinyltoluene, vinyl chloride, (
Examples include meth)acrylonitrile and the like.

Monomer (g) and monomer (h) are important components that affect the flexibility of the coating film of the coating composition, the blocking resistance, and the Tg of the obtained polymer. Taking into consideration, monomer (2) may be used alone or in combination of two or more.
The amount used is 10 to 98 wt-u% in component B,
The amount of nanatsuma (h) used in component B is 0 to 80% by weight.

The copolymer of component B has an average molecular weight of 5000 to 150.
000, preferably 8000 to 80,000, and Tg is 20°C to 100°C, preferably 25°C to 7
It is 0°C. If the average molecular weight is less than 5,000, it will be difficult to exhibit the properties as a coating composition, and sufficient heat seal strength will not be obtained.

When it exceeds 150,000, the adhesion with the film decreases,
The viscous flow properties to obtain good heat sealability are
It becomes.

Note that the average molecular weight referred to here is a number average molecular weight. Further, if Tg exceeds 100°C, the coating film of the coating composition will be hard, the flexibility will be reduced, and the heat sealability will be impaired.

In the present invention, the ratio of the A component to the B component is 10
It is necessary to use 0.5 to 20 parts by weight of component A, preferably 2 to 10 parts by weight, and 0.5 to 10 parts by weight.
If the amount is less than parts by weight, antistatic properties will not be exhibited. On the other hand, 2
If it exceeds 0 parts by weight, the viscosity of the aqueous dispersion increases, polymerization stability deteriorates, and blocking resistance decreases, which is not preferable.

It is thought that the antistatic properties exhibited in the coating film of the coating composition of the present invention are mainly due to the ion conduction mechanism of electricity by the monomer (d) K having sulfonic acid or its salt. The contribution of is thought to be small.

<Production of aqueous emulsion (■)> Next, a method for producing the emulsion composition (n) of the present invention will be described.

Monomer (d) and monomer (e) are polymerized in advance in an aqueous medium. In addition, in order to remove oxygen from the polymerization system, it is preferable to substitute it with nitrogen or the like.

As a polymerization initiator, t-butyl hydroperoxide,
2,5-dimethyl-2,5-di(t-butylpenoloxy)hexane, peroxides such as hydrogen peroxide, potassium persulfate, ammonium persulfate, or combinations of these polymerization initiators with various reducing agents. Redox initiator by combination,
Furthermore, polymerization can be initiated using a water-soluble azo compound such as 2,2-azobis(2-amidinopronopronone) hydrochloride.

The polymerization temperature, pressure within the polymerization system, and stirring method should be selected depending on the type and combination of initiators.

The polymerization temperature is preferably 20 to 85°C when a redox initiator is used for boat fishing, and 40 to 120°C when a peroxide or azo initiator is used.

In the presence of the polymer of component A obtained in this manner, B
A monomer mixture of the components and an initiator are added and polymerized in an aqueous medium. The initiator and polymerization temperature used in this case may be the same as those used in producing the polymer of component A, but they do not necessarily have to be the same.

The aqueous emulsion composition (n) of the present invention can be produced by utilizing the property of the polymer of component A to improve dispersion stability in emulsion polymerization and using the polymer as a dispersion stabilizer. Although the resulting aqueous emulsion composition (113) does not substantially contain an emulsifier, a small amount of an emulsifier or a protective colloid may be supplementarily added as necessary.

The aqueous emulsion composition (II) obtained in this way is stable as it is, but in some cases, bases such as ammonia, sodium hydroxide, potassium hydroxide, trimethylamine, diethylamine, trimethylamine, jetanolamine, and triethylamine are used. It is preferable to adjust the − with a chemical substance, as this further increases stability. Volatile bases such as ammonia and diethylamine are preferred;
Ammonia is particularly preferred.

The method for obtaining the aqueous emulsion composition (n) is also described in JP-A-54-95636.

[Mixing of coating composition]

In the present invention, the aqueous composition (1) and the aqueous emulsion composition (II) have a solid content weight ratio of (1) / <
II) = 5-50/95-50, the coating composition of the present invention can be obtained.

If the composition (1) is less than 5% by weight, the water resistance of the coating film of the coating composition may not be sufficient, and the applied film may whiten due to water or steam, and if it exceeds 50% by weight, The coating composition has insufficient antistatic properties and is not suitable for high-speed automatic packaging.

Furthermore, when mixing the aqueous composition (1) and the aqueous emulsion composition (n), lubricants, antiblocking agents, antistatic agents, plasticizers, antioxidants, stabilizers, etc. may be added as necessary. It's okay.

[Coating on film]

Next, the film that is the coating substrate for the coating composition of the present invention will be explained.

The film targeted by the present invention is a plastic film, and includes, for example, a 4-lyolefin film such as a polyethylene film, a propylene film, and a polybutene film, a polyester film, and a nylon film. These may be -axially stretched films, biaxially stretched films, or unstretched films. In particular, the coating composition of the present invention is effective on polyolefin films such as biaxially oriented polypropylene films. Moreover, the thickness of the film may also be a thickness called sheet-like.

Also, the surface of the base film is the same! However, it is preferable to treat the polyolefin film so that the contact angle with water is 85 degrees or less.
It is preferable to activate the surface by corona discharge treatment, oxidizing agent treatment, etc. before use.

The coating composition of the present invention is applied to the film surface by a known coating method such as a gravure coater method, a reverse roll coater method, a lot coater method, a dip coater method, an air knife coater method, etc., to a thickness of drops. be able to.

The amount of coating at this time is at least O,l 97m2 or more,
Particularly preferred is 0.29 to 3')7 m2. The amount of coating is o,
If it is less than 19/m 2 , the heat sealing strength of the film will be weak and it will not be practical as a packaging film.

Furthermore, if the coating amount exceeds 3 g/m2, the drying time of the coating film tends to be long, resulting in poor productivity.

After the coating composition is coated on the film surface, a known method using a commonly used dryer such as a hot air dryer, an infrared dryer, or a steam dryer used to dry the film-like substrate is carried out. You can dry it by any method.

(Effects of the invention) The effects of the coating composition of the invention are as follows.

■ Since it is a water-based coating composition, there are no problems of fire, explosion, toxicity to the human body, or air pollution, and there is no problem of residual solvent in the applied film.

■ Because the aqueous composition of (1) and the aqueous emulsion composition of (It), which are dissolved in water or dispersed in particles of O,t microns or less, were mixed, a glasstic film that could not be expected from each of them alone was created. Excellent adhesion to.

■ The coating composition of the present invention contains highly polar functional groups, especially sulfonic acids or salts thereof, and carboxylic acids. Since it contains more xyl groups on the particle surface than normal emulsions, it has low compatibility with organic solvents, especially aliphatic organic solvents, and therefore the film coated with the coating composition of the present invention When printing, the organic solvent is absorbed into the plastic film that is the base material, and the film does not swell and wrinkle.

(2) Compared to coating agents made of ordinary emulsions, the coating composition of the present invention has excellent film-forming properties and is difficult to block.

This means that during film formation, the aqueous composition of (1), which is a more finely dispersed or dissolved polymer, enters between the particles of the aqueous emulsion composition of (n), and the particles of the aqueous emulsion composition of (n) It is thought that it is easy to connect the gaps to form a dense film, which makes blocking difficult.

■Also, even if the part consisting of the conductive vinyl monomer in the aqueous emulsion composition (n) is an electrolyte, the aqueous composition (1) will penetrate between the particles of the aqueous emulsion composition (II), forming a dense Since it forms a film, the coating film has good water resistance.

(2) Since the coating composition contains a polymer containing a conductive vinyl monomer, it provides a coating film with good antistatic properties.

(Use of the invention) The coating composition of the present invention is suitable for use in coating films, and the coating film thereof has both excellent antistatic properties and heat-sealing properties, and the coated film is particularly suitable for high-speed coating. It is suitable not only as a packaging material for the outer packaging of cigarettes, confectionery, etc., which are packaged using overlapping automatic packaging machines, but also as a general packaging film.

Note that it may be applied to paper, cellophane, textile products, plastics, leather, inorganic materials, etc. other than plastic films.

In addition, the coating film of the coating composition of the present invention has excellent antistatic properties, and can be used not only as a coating for packaging films, but also as an antistatic agent or as a conductive agent for electrostatic recording paper and electrically conductive recording paper. Can be used as layer material.

Further, the film of the present invention can be further top coated with a solution or emulsion of a vinylidene chloride resin. The thickness of the top coat layer at this time is not particularly limited, but is preferably 0.5 to 6 microns.

(Example) The present invention will be further described with reference to Examples. In the Examples and Comparative Examples, unless otherwise specified, % by weight is indicated.

In addition, in the Examples and Comparative Examples, the performance of the obtained coating film is a value determined by the following measuring method.

1. Preparation of sample film A coating composition prepared by mixing an aqueous composition and an aqueous emulsion composition was diluted so that the solid content was 20%,
To this, 4 parts of an aqueous dispersion of carnauba wax (20% solids) per 100 parts solids of the coating composition.
Part and fine powder colloidal silica (product name: Thyroid 0.
3 parts of the coating liquid was applied to the surface of a corona discharge-treated biaxially stretched plastic film (thickness: 20μ) using a bar coater until the solid content was 1.59/m2.
A sample film was obtained by coating the film and drying it for 30 seconds at a temperature of 110°C.

2. Test method Charging characteristics: Using a static honest meter (Shishido Shokai), applying a voltage of 10kV, temperature 20℃,
The half-life time of attenuation of the charged voltage was measured in an atmosphere with a humidity of 65%. A time of 90 seconds or less is suitable for practical use.

Heat-sealing strength: The film-coated surfaces were put together and heat-sealed for 1 second at 120° C. and a pressure of 1:9/2 F using a part type heat sealer. After leaving this film in an atmosphere with a temperature of 20°C and a humidity of 65% for 24 hours, the force required to peel off the film at a speed of I OOMm/min was measured using a tensile tester. did. 509/15 inches or more is suitable for practical use.

Transparency... Four sample films were stacked and the haze value was measured using a direct reading haze meter (manufactured by Toyo Seiki Seisakusho, Model 206).

◎... Haze value less than 10% O... Haze value 10% or more and less than 16% ×... Haze value 16 qb or more ◎ and ○ are suitable for practical use.

Water whitening resistance...Immerse the sample film in hot water at 80℃ for 100℃
After the film was placed in the cIrL position for 15 seconds, the whitening state of the coated surface of the film was observed.

◎・・・The paint film has not whitened at all. ○...The paint film is slightly whitened. ×...Most of the paint film has turned white. O and O are suitable for practical use.

Synthesis Example 1 fc2 equipped with reflux condenser, thermometer, stirrer, and dropping funnel
1. Nonylphenyl ether polyethylene glycol sulfonic acid sodium 12, 29 and water 510 in a Sebapurfura filter
g was charged and heated to 80° C. with stirring under a nitrogen atmosphere.

Next, add 40g of methacrylic acid, 70g of ethyl acrylate, 290y of methyl methacrylate, and 6g of lauryl mercaptan, and 369.5% sodium bisulfite aqueous solution of 369.5% sodium bisulfite aqueous solution 369. Drip over time. After the dropwise addition was completed, the mixture was kept at 80° C. for 1 hour, and then 145 g of 4% aqueous ammonia was gradually added. Thus, the viscosity is 1080 eps and the solids concentration is 34.8.
An aqueous solution of acrylic I remer with a concentration of -7.8% was obtained.

Synthesis Example 2 21 with reflux condenser, thermometer, stirrer, and dropping funnel
In a separate flask, add 12.29 g of sodium nonyl phenyl ether polyethylene glycol sulfonate and 510 g of water.
9 was charged and heated to 80° C. with stirring under a nitrogen atmosphere.

Next, 40 g of methacrylic acid, 709 g of ethyl acrylate, a mixed solution of 290 g of methyl methacrylate and 69 g of 29lyl mercadetane, and 36 g of a 5% aqueous solution of ammonium persulfate and 36.5% aqueous sodium bisulfite solution were added to each of 2 g. Drip over time. After the dropwise addition was completed, the mixture was kept at 80° C. for 1 hour and then cooled. Thus, the viscosity is 15 cps,
An aqueous composition having a solid concentration of 40.8% and a pH of 2.2 was obtained.

Synthesis Example 3 21 with reflux condenser, thermometer, stirrer, and dropping funnel
A sepapure flask was charged with 3.2 g of sodium lauryl sulfate and 540 g of water containing 1 g of potassium persulfate, and heated to 90° C. with stirring under a nitrogen atmosphere.

This was then added with 16.2 g of methacrylic acid, 97.8 g of ethyl acrylate and 22 g of methyl methacrylate.
6g of lauryl mercaptan and 2.6g of lauryl mercaptan.
It dripped over time.

After the dropwise addition, 60g of isoglobil alcohol and 30g of calpitol were added after keeping at 80℃ for 2 hours, and then 10g of
After adding 22 g of % ammonia water, the mixture is cooled. Thus, the viscosity of the particles dispersed in the 0.04 micron polymer particles is 17
An aqueous composition having a solid content of 60 epS, a solid content concentration of 34.8, and a pH of 7.8 was obtained.

Synthesis Example 4 21 with reflux condenser, thermometer, stirrer, and dropping funnel
In a separate flask, there are 961 parts of water, 30.89 parts of sodium p-styrene sulfonate, and 0 parts of acrylic acid.
．． 29, 1.5 g of hydroxyethyl methacrylate, 2.7 g of methyl methacrylate, 2.9 g of ethyl acrylate
, 2.7 g of styrene, 0.0 g of t-dodecyl mercaptan. I
I was charged, and the temperature was raised to 85° C. while stirring under a nitrogen atmosphere. To this, add 0.2 g of potassium persulfate to 1 part of water.
Add an aqueous solution of 8Ii and polymerize for 60 minutes.

Next, a mixed solution of acrylic acid s, sg, hydroxyethyl methacrylate 51.6 g, methyl methacrylate 94.69, ethyl acrylate 176, jil, styrene 94.69 and t-dodecyl mercaptan 4.4 g and potassium persulfate. An aqueous solution of 2 g dissolved in 162.9 g of water was added dropwise from separate dropping funnels over a period of 2 hours. After completion of the dropwise addition, polymerization was further carried out at 85° C. for 3 hours, and then cooled. Thus, the viscosity is 23 cps, the solids concentration is 30 parts,
An aqueous emulsion composition with a pH of 2.1 was obtained.

Synthesis Example 5 L7'c equipped with reflux condenser, thermometer, stirrer, and dropping funnel
9339 water, 18.39 g of sodium p-styrene sulfonate, and 0.2 g of potassium persulfate were placed in a 2 L sepapure flask under a nitrogen atmosphere, and heated at 85°C for 60 g.
Polymerize for 0 minutes. Next, hydroxyethyl methacrylate 68.8.1 methyl methacrylate 197.29, ethyl acrylate 183.4 g, acrylic acid 9.29 and t
- A mixed solution of 4.6 p of dodecyl mercaptan and an aqueous solution of 4.4 g of potassium persulfate dissolved in 193 g of water are each added dropwise from separate dropping funnels over a period of 2 hours. After completion of the dropwise addition, polymerization was further carried out at 85°C for 3 hours, and after cooling,
5.39 oz of aqueous ammonia was added. Thus, the viscosity 23
cps.

An aqueous emulsion composition with a solids content of 1°30 and a pl (7.2) was obtained.

Examples 1 to 3 The acrylic polymer aqueous solution obtained in Synthesis Example 1 and the aqueous emulsion composition obtained in Synthesis Example 4 were mixed in the proportions shown in Table 1 (
Adjust the coating liquid by thoroughly mixing (solid content ratio),
Its performance was evaluated. The evaluation results are shown in Table 2. Example 4 The aqueous composition obtained in Synthesis Example 3 and the aqueous emulsion composition obtained in Synthesis Example 4 were thoroughly mixed at the ratio (solid content ratio) shown in Table 1. The coating solution was adjusted and its performance was evaluated. The evaluation results are shown in Table 2.

Example 5 The aqueous composition obtained in Synthesis Example 3 and the aqueous emulsion composition obtained in Synthesis Example 5 were thoroughly mixed in the proportions (solid content ratio) shown in Table 1 to prepare a coating liquid and evaluate its performance. was evaluated. The evaluation results are shown in Table 2.

Example 6 The acrylic polymer aqueous solution obtained in Synthesis Example 1, the aqueous composition obtained in Synthesis Example 3, and the aqueous emulsion composition obtained in Synthesis Example 5 were mixed at the ratios (solid content ratio) shown in Table 1. A coating solution was prepared by mixing the coating solution, and its performance was evaluated. The evaluation results are shown in Table 2.

Comparative Example 1 The aqueous Emashif 3 composition obtained in Synthesis Example 4 was used as a coating liquid, and its performance was evaluated.

The evaluation results are shown in Table 2.

Comparative Example 2 A coating liquid was prepared by thoroughly mixing the acrylic obtained in Synthesis Example 1, the aqueous reamer solution obtained in Synthesis Example 1, and the aqueous emulsion composition obtained in Synthesis Example 4 in the proportions (solid content ratio) shown in Table 1. , and evaluated its performance. The evaluation results are shown in Table 2.

Comparative Example 3 A coating liquid was prepared by thoroughly mixing the aqueous dispersion obtained in Synthesis Example 2 and the aqueous emulsion composition obtained in Synthesis Example 4 at the ratio (solid content ratio) shown in Table 1, and its performance was evaluated. evaluated. The evaluation results are shown in Table 2.

Comparative Example 4 Sodium lyacrylate (Nearon A-2OL manufactured by Toagosei Kagaku Kogyo ■) and the aqueous emulsion composition obtained in Synthesis Example 4 were blended to a solid content ratio of 30 to 0, and thoroughly mixed. A coating liquid was prepared and its performance was evaluated. The evaluation results are shown in Table 2.

Table 2 In addition, the value was used for the Tg of the homopolymer of each monomer.

Acrylic acid: 379 K Ethyl acrylate: Methacrylic acid at 251: Methyl methacrylate at 458: Hydroxyethyl methacrylate at 378 = Styrene at 328°: Number below 373 K

Claims (2)

[Claims] (1) (I) (a) α,β-unsaturated carboxylic acid having at least one carboxyl group and (b) (meth)acrylic acid alkyl ester, the alkyl group having 1 to 4 carbon atoms ) at least one of
A copolymer consisting of a seed and, if necessary, (c) a vinyl monomer that can be radically copolymerized with the above (a) and (b), and the acid value of the polymer is 10 to 200 and As component A of composition (II), a copolymer in which at least 30% of the carboxyl groups contained in the polymer form a salt is dissolved or dispersed in an aqueous medium with a particle size of 0.1 micron or less. (d) 100 to 25% by weight of at least one conductive vinyl monomer having sulfonic acid or its salt in the molecule; and (e) 0 to 75% by weight of a vinyl monomer that can be radically copolymerized with (d) above. A monomer mixture of 0.5 to 2
0 parts by weight As component B (f) α, β having at least one carboxyl group
- 0 to 10% by weight of at least one unsaturated carboxylic acid (g) 10 to 98% by weight of at least one (meth)acrylic acid alkyl ester, the alkyl group of which has 1 to 12 carbon atoms (h ) Monomer mixture 1 consisting of 0 to 80% by weight of a vinyl monomer capable of radical copolymerization with the above (f) and (g)
The solid content weight ratio A coating composition obtained by mixing (I)/(II) = 5 to 50/95 to 50. (2) A plastic film coated with the coating composition according to claim 1.