WO2007086266A1

WO2007086266A1 - Polyester resin aqueous dispersion and method for producing same

Info

Publication number: WO2007086266A1
Application number: PCT/JP2007/050405
Authority: WO
Inventors: Mamiko Takesue
Original assignee: Unitika Ltd.
Priority date: 2006-01-24
Filing date: 2007-01-15
Publication date: 2007-08-02
Also published as: JP5241240B2; KR20080084843A; JPWO2007086266A1; KR101004241B1

Abstract

Disclosed is a polyester resin aqueous dispersion capable of forming a coating film having excellent adhesion. Also disclosed is a method for producing such a polyester resin aqueous dispersion. Specifically disclosed is a polyester resin aqueous dispersion characterized by containing a polyester resin having a melting point of not more than 100˚C, a crystal melting enthalpy of 2-12 J/g, an acid value of 2-30 mgKOH/g and a number average molecular weight of not less than 5,000. Also specifically disclosed is a method for producing such a polyester resin aqueous dispersion, wherein an organic solvent solution of a polyester resin is dispersed into water together with a basic compound, thereby forming a polyester resin aqueous dispersion by phase inversion emulsification. This method for producing such a polyester resin aqueous dispersion is characterized in that the phase inversion emulsification is carried out at 10-40˚C.

Description

Specification

Polyester resin aqueous dispersion and method for producing the same

Technical field

The present invention relates to a polyester resin aqueous dispersion capable of forming a resin coating excellent in adhesion.

Background art

[0002] A polyester resin is a coating resin, and is excellent in processability of a film, resistance to organic solvents (solvent resistance), weather resistance, adhesion to various substrates, etc. It is used in large quantities as a binder component in the fields such as inks, adhesives and coatings.

Particularly in recent years, there has been a tendency for the use of organic solvents to be restricted due to environmental protection, resource saving, hazardous materials regulations under the Fire Service Law, etc., and the ability to improve workplace environment. As a binder, polyester resin aqueous dispersions of polyester resin finely dispersed in an aqueous medium have been actively developed.

For example, Patent Documents 1 to 4 propose a polyester resin aqueous dispersion in which a high molecular weight polyester resin having a low acid value is dispersed in an aqueous medium, and when a strong aqueous dispersion is used, It is described that a film excellent in performance such as processability, water resistance, solvent resistance, etc. can be formed. The aqueous dispersions of polyester resin described in these documents were dispersed in an aqueous medium by neutralizing the carboxyl groups of the polyester resin with a basic mixture. It is a so-called self emulsification type polyester resin aqueous dispersion, and in order to stably disperse the polyester resin in an aqueous medium, the polyester resin used has a carboxyl group corresponding to an acid value of 8 mg KOHZg or more. It was necessary. As a result, if the upper limit of the molecular weight of polyester resin is limited and adhesion may become insufficient, problems will remain! /.

[0005] In order to solve this problem, Patent Document 5 disperses a high molecular weight polyester resin having an acid value of 2 mg KO HZg or more and less than 8 mg KOHZg and a high molecular weight polyester resin in an aqueous medium. Aqueous polyester resin dispersions have been proposed. From this proposal, Although it is possible to form a film excellent in a certain level of adhesion, processability and water resistance, it is possible to achieve polyester resin aqueous dispersions that exhibit adhesion comparable to organic solvent-soluble adhesives! / I did not hesitate.

Patent Document 1: Japanese Patent Application Laid-Open No. 9-296100

Patent Document 2: Japanese Patent Application Laid-Open No. 2000-26709

Patent Document 3: JP-A 2000-313793

Patent Document 4: Japanese Patent Application Laid-Open No. 2002-173582

Patent Document 5: International Publication 2004Z037924 Pamphlet

Disclosure of the invention

Problem that invention tries to solve

The present invention has been made in view of the above circumstances, and provides a polyester resin aqueous dispersion capable of forming a film excellent in adhesion while having excellent storage stability, and a method for producing the same. The purpose is to

Means to solve the problem

As a result of intensive studies to solve the above problems, the present inventors can easily obtain an aqueous dispersion by using a polyester resin having specific thermal properties. The coating formed from the aqueous dispersion was found to be excellent in adhesion and completed the present invention.

That is, the present invention is characterized by containing a polyester resin having a melting point of 100 ° C. or less, a heat of crystal fusion of 2 to 12 jZg, an acid value of 2 to 30 mg KOHZg, and a number average molecular weight of 5000 or more. It relates to a polyester resin aqueous dispersion.

The present invention is also a method of producing an aqueous polyester resin oil dispersion by phase inversion emulsification, by dispersing an organic solvent solution of polyester resin together with a basic compound in water, wherein 10 to 40 ° The method for producing the aqueous polyester resin dispersion according to any one of claims 1 to 4, characterized in that phase inversion emulsification is carried out with C.

Effect of the invention

[0010] The polyester resin aqueous dispersion of the present invention has adhesiveness, in particular, a place to be bonded by heat press. As a resin coating with excellent low temperature adhesion properties can be formed, it is possible to form an anchor coating agent for metal plates and films, and an adhesive for laminating substrates such as fiber, paper, metal and resin.

Industrial application value is extremely high because it can be used in applications such as paints and inks for decorating substrates, and their performance can be improved. In particular, the polyester resin aqueous dispersion of the present invention achieves sufficient adhesion at a low temperature of 120 ° C. or less. The polyester resin aqueous dispersion of the present invention is excellent in storage stability.

BEST MODE FOR CARRYING OUT THE INVENTION

(Polyester Resin Aqueous Dispersion)

The polyester resin aqueous dispersion (hereinafter simply referred to as "aqueous dispersion") of the present invention contains a specific polyester resin.

The polyester resin contained in the aqueous dispersion of the present invention must have a melting point of 100 ° C. or less, and preferably 40 to 95 ° C., preferably 42 to 90 ° C. Is the best. The aqueous dispersion generally has a fine particle resin melted and formed into a film by heating at a temperature sufficiently higher than the melting point. When the melting point exceeds 100 ° C., it is on a PET T film which is a versatile substrate. Film formation does not occur sufficiently at a drying temperature of 120 ° C., and adhesion between the film and the film is poor. Therefore, when the adhesion is evaluated, interfacial peeling occurs and the adhesion deteriorates. In addition, since the resin is not sufficiently melted at a temperature of 80 to 120 ° C. also for the heat press temperature for bonding, the adhesiveness is not exhibited. On the other hand, although it is possible to melt the resin by raising the heat press temperature to 160 ° C, it is not preferable because the PET film of the base material shrinks and deforms.

In addition, the heat of crystal fusion of the polyester resin needs to be 2 to 12 jZg, and 3 to 10 jZg, which is preferred: L1 JZ g, is optimum. In the present invention, by using a polyester resin exhibiting a heat of crystallization in the above-mentioned range in particular, the cohesion is improved by the crystallization of the polyester, and the adhesiveness is improved by sufficient curing. If the heat of crystal fusion is less than 2jZg, the cohesion of the polyester resin can not be improved and sufficient curing can not be obtained, and a film having excellent adhesion can not be obtained. If the heat of crystal fusion exceeds 12 jZg, the solubility in organic solvents is poor, so production by phase inversion emulsification is difficult, or the storage stability of the aqueous dispersion is deteriorated.

The acid value of the polyester resin needs to be 2 to 30 mg KOHZg, 3 to 25 mg KOH From the viewpoint of adhesion at low temperatures where Zg is preferred, 4 to 20 mg KOHZg is optimum. When the acid value is less than 2 mg KOHZg, it is difficult to obtain a uniform aqueous dispersion. In addition, when the acid value exceeds 30 mg KOHZg, the number average molecular weight of the polyester resin becomes small, and a film excellent in adhesiveness can not be obtained.

The number average molecular weight of the polyester resin needs to be 5,000 or more, and the force S is preferably 7, 000-40, 000, 9,000-30, 000, particularly 10,000-25, It is the power that is 000 ^ optimum. If the number average molecular weight is less than 5,000, a film having excellent adhesion can not be obtained.

The polyester resin contained in the aqueous dispersion of the present invention is (1) a method of polycondensation of a predetermined acid component and an alcohol component, (2) a polybasic acid component after such polycondensation. And (2) addition of an acid anhydride after polycondensation, and the like. At this time, by adjusting various conditions, it becomes possible to control the melting point, the heat of crystal fusion, the acid value and the molecular weight of the polyester resin, and as a result, it is possible to produce the polyester resin meeting the requirements of the present invention. From the viewpoint of such controllability of physical properties, the method (2) is preferable.

For example, as will be described in detail later, aromatic dicarboxylic acids, aliphatic dicarboxylic acids, etc. are used as the acid component, but when the proportion of aliphatic dicarboxylic acid in the acid component is increased, the crystal melting point is increased. The higher the heat, while the lower the proportion of aliphatic dicarboxylic acids, the higher the melting point of the butter.

Also, for example, as described in detail later, aliphatic glycol and the like are used as the alcohol component, but when the proportion of aliphatic glycol, in particular 1,4 butanediol is increased, the heat of crystal melting of sugar is used. Increases while decreasing the proportion of aliphatic glycols, especially 1,4 butanediol, decreases the heat of crystal fusion of sugars.

Also, for example, when the amount of the polybasic acid component used for depolymerization is increased, the number average molecular weight of the salt decreases and the acid value increases. On the other hand, when the amount of the polybasic acid component used is decreased, the number average molecular weight of the fat increases and the acid value decreases. At this time, when the tribasic or higher functional polybasic acid component is used, the increase in acid value is more remarkable than when the bifunctional type is used.

As the acid component constituting polyester resin, at least a polybasic acid component is used, and it is necessary to If necessary, monocarboxylic acids are used.

Examples of the polybasic acid component include aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids.

Specific examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid, phthalic acid, phthalic anhydride, naphthalene dicarboxylic acid, biphenyl dicarboxylic acid and the like.

Specific examples of aliphatic dicarboxylic acids include, for example, oxalic acid, malonic acid, succinic acid, succinic anhydride, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, hydrogenated dimer acid And unsaturated aliphatic dicarboxylic acids such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic acid, citraconic acid, citraconic acid, dimer acid and the like.

Specific examples of the alicyclic dicarboxylic acid include, for example, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid and 2,5-norbornene dicarboxylic acid. Examples thereof include acids, 2,5-norbornene dicarboxylic acid anhydride, tetrahydrophthalic acid and tetrahydrophthalic anhydride.

Further, as the polybasic acid component, a small amount of 5-sodiumsulfoisophthalic acid and 5-hydroxyisophthalic acid can be used, if necessary.

A tribasic or higher functional polybasic acid can also be used, and examples thereof include trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid, trimellitic anhydride, pyromellitic anhydride, benzozo phenone anhydride tetracarboxylic acid, trimesin. It may contain an acid, ethylene glycol bis (anhydrotrimellitate), dalycerol tris (anhydrotrimellitate), 1,2,3,4-butanetetracarboxylic acid and the like. The trifunctional or higher polybasic acid is preferably used as a depolymerization agent, in which case the content of the trifunctional or higher polybasic acid in the polyester resin of the present invention constitutes the polyester resin. It is preferred that the amount be less than 5 mol% with respect to the total acid component to be /.

Specific examples of the monocarboxylic acid include, for example, fatty acids such as lauric acid, myristic acid, normitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, benzoic acid, p-tert-butyl benzoic acid, cycloaliphatic acid Hexanoic acid, 4-hydroxyphenylstearic acid etc Be

As the alcohol component constituting the polyester resin, at least a polyhydric alcohol component is used, and a monoalcohol is used as needed.

Examples of polyhydric alcohol components include aliphatic glycols, alicyclic glycols, ether bond-containing dacols, and the like.

Specific examples of the aliphatic glycol include, for example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 2-methyl-1,3-propanediol, 1,5-pentanediol, Examples include neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-acetyl-2-butylpropanediol and the like.

Specific examples of the alicyclic glycol include, for example, 1,4-cyclohexanedimethanol and the like.

Specific examples of the ether bond-containing dacyl include, for example, bisphenols such as diethylene glycol, triethylene glycol, dipropylene glycol, and further, bis (4- (hydroxy) phenyl) propane. Ethylene oxide adducts of phenol A), ethylene oxide adducts of bisphenols (bisphenol S) such as bis [4- (hydroxyethoxy) phenyl] sulfone, polyethylene glycol, polypropylene adducts And polytetramethylene glycol.

Examples of the trifunctional or higher functional polyhydric alcohol include glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, and the like.

[0027] Specific examples of monoalcohols include, for example, stearyl alcohol, 2-phenoxyethanol and the like.

In addition to the above-mentioned acid component and alcohol component, polyester resin is, for example, lactic acid, β

It may also contain monohydroxymonocarboxylic acids such as hydroxybutyric acid, ヒドロキシ hydroxybenzoic acid and aliphatic ratatones such as Ζ or ε-prolataton, δ- valerolataton. Monohydroxy monocarboxylic acid and aliphatic ratatone should be considered as components applicable to both acid and alcohol components. For example, when aliphatic ratatone is contained, “total acid component” and “total acid content” as a standard when expressing the content of each monomer The content of the aliphatic ratatone is added to any of the “rucol components” to represent the content of each monomer.

[0029] The polyester resin used in the present invention contains at least an aromatic dicarboxylic acid and an aliphatic glycol as the components among the above components.

The content of the aromatic dicarboxylic acid is the total acid components constituting the polyester榭脂30-70 mole ^_0/0, a Japanese 〖This 35-65 mole ^_0/0, and the content of the aliphatic glycol 70 for all Norre n- Honoré component [this: LOO Monore ^_0/0, preferably ί or 85 to: LOO Monore ^_0/0, JP [this 1:90 00 more preferred embodiment is preferably tool that is mol% The aliphatic glycol content is 100 mol%. If the amount of aromatic dicarboxylic acid is less than 30 mol%, the heat of crystal fusion tends to be higher than the range of the present invention. When the amount of aromatic dicarboxylic acid exceeds 70 mol%, the melting point tends to be higher than the range of the present invention, which is not preferable. If the aliphatic glycol content is less than 70 mol%, the heat of crystal melting tends to be lower than the range of the present invention, which is not preferable.

The aromatic dicarboxylic acid preferably contains at least terephthalic acid, and its content is preferably 15 to 50% by mole, particularly preferably 18 to 45% by mole, based on the total acid component constituting the polyester resin. If the amount of terephthalic acid is less than 15 mol%, the heat of crystal fusion tends to be out of the range of the present invention. When the amount of terephthalic acid exceeds 50 mol%, the melting point and the heat of crystal fusion tend to be higher than the range of the present invention, which is not preferable.

The aromatic dicarboxylic acid is also more preferable in terms of adhesion, and includes, in an aspect, terephthalic acid and isophthalic acid, and further preferably, in the aspect, only terephthalic acid and isophthalic acid are effective. In those embodiments, the total content of terephthalic acid and isophthalic acid from 35 to 65 mol% based on the total acid components constituting the polyester榭脂, 40 to 65 mole ^_0/0 force preferably in particular, also terephthalic acid The content ratio of isophthalic acid to the molar ratio (: / ΙΡΑ) is 30/70 /: LOO / 0, especially 40/60 to 70/30 force ^ preferred! / ,.

As described above, when terephthalic acid (TPA) and isophthalic acid (IPA) are used in combination, for example, when the amount of IPA that decreases TPA is reduced, the heat of fusion increases.

Also, for example, increasing the amount of IPA to reduce TPA lowers the heat of fusion.

For example, if TPA is increased and IPA is decreased, the melting point and heat of fusion increase.

Also, for example, if TPA is increased and IPA is increased, the melting point is increased. The aliphatic glycol preferably contains at least 1,4 butanediol from the viewpoint of adjusting the melting point and the heat of crystal fusion within the scope of the present invention, and the content thereof is the whole of the polyester resin. 70-100 mole ^_0/0 for alcohol component, in particular 80 to: LOO molar% is preferred.

If the amount of 1,4-butanediol is less than 70% by mole, the heat of crystal fusion becomes lower than the range of the present invention, which is not preferable.

The polyester resin preferably contains, in addition to the above aromatic dicarboxylic acid and aliphatic glycol, an aliphatic dicarboxylic acid and Z or an aliphatic ratatone. More preferably, an aliphatic dicarboxylic acid is contained, or an aliphatic dicarboxylic acid and an aliphatic ratatone are contained.

The aliphatic dicarboxylic acid is preferably the above-mentioned saturated aliphatic dicarboxylic acid, more preferably a C4-C10 saturated aliphatic dicarboxylic acid such as succinic acid, succinic anhydride, adipic acid, azelaic acid or sebacic acid, most preferably Aliphatic ratatones which are succinic acid and Z or sebacic acid are preferably ε-force proratatons.

The content of each aliphatic dicarboxylic acids or aliphatic Rataton usually 30 to 70 mol ^_0/0 for the total acid component, particularly 35 to 65 mole ^_0/0 force child preferable. When both aliphatic dicarboxylic acid and aliphatic ratatone are contained, the total amount thereof may be within the above range.

In the aqueous dispersion of the present invention, the above-mentioned polyester resin is dispersed in an aqueous medium, and more specifically, a part or all of the carboxyl groups of the above-mentioned polyester resin is a basic compound. It is an aqueous dispersion to be neutralized. The basic compound neutralizes the noreboxyxole group of the polyester resin to form a caneboxynoleite, and the electric repulsion between the particles causes the polyester resin fine particles to be stable without aggregation. Distributed to

As the basic complex, organic amine having a boiling point of 250 ° C. or less, or 160 ° C. or less, or ammonia is preferable from the viewpoint of easy volatilization at the time of film formation. Specific examples of such organic amines include tolylamine, N, N jetylethanolamine, N, N dimethylethanolamine, aminoethanolamine, N-methyl-N, N diethanolamine , Isopropylamine, Iminobispropylamine, Etylamine, Jetylamine, 3-Ethoxypropylamine, 3-Diethylaminopropylamine, sec-Butylamine, Propylamine, Methylaminopropylamine, Dimethylamino Propylamine, methyliminobispropylamine, 3-methoxypropylamine, monoethanolamine, diethanolamine, triethanolamine, morpholine, N-methylmorpholine, N-ethylmorpholine and the like can be mentioned. Among them, ammonia and triethylamine are particularly preferable.

The content ratio of the polyester resin in the aqueous dispersion of the present invention can be appropriately selected depending on the film forming method, the type of the coated material, and the thickness and performance of the desired resin coating, The content is not particularly limited, but it is preferably 5 to 60% by mass, based on the total amount of the aqueous dispersion, in terms of maintaining an appropriate viscosity at the time of coating and expressing a good film forming ability. Mass% is optimal. The particle size of the polyester resin is optimally 200 nm or less, which is preferably 300 nm or less in terms of volume average particle size, from the viewpoint of maintaining good storage stability.

The aqueous medium constituting the aqueous dispersion of the present invention is a medium composed of a liquid containing water as a main component, and may partially contain the above-mentioned basic binder and an organic solvent described later. Although it is good, the content of organic solvent in the polyester resin aqueous dispersion is 3 in order to improve the environmental problems and the working environment, and to reduce the residual organic solvent that adversely affects the resin film properties. 1% by mass or less is optimum, preferably 1% by mass or less.

[0039] (Manufacturing method)

Next, the method for producing the polyester resin aqueous dispersion of the present invention will be described. The aqueous dispersion of the present invention can be produced by phase inversion emulsification by dispersing a solution of polyester resin in an organic solvent together with a basic compound in water. Specifically, in the aqueous dispersion, a step of dissolving polyester resin in an organic solvent (dissolution step) and a step of dispersing an organic solvent solution of polyester resin together with a basic compound in water (phase inversion emulsification) It can be manufactured in 2 steps with step). Next, by the step of removing the organic solvent and removing the organic solvent thus obtained (solvent removal step), an aqueous dispersion in which the content of the organic solvent is reduced can be obtained. If necessary, filtration and removal of undispersed substances and aggregates results in an aqueous dispersion in a uniform state which can not be observed, such as precipitates and phase separation. Each process will be described.

First, the dissolution step will be described. In the dissolving step, the polyester resin is dissolved in an organic solvent. At this time, the concentration of the polyester resin in the organic solvent solution of the polyester resin to be obtained is preferably in the range of 10 to 60% by mass, and the range of 20 to 50% by mass is optimum. When the concentration of the polyester resin in the solution exceeds 60% by mass, the increase in viscosity becomes large when mixed with water in the next phase inversion emulsification step, and a uniform aqueous dispersion may not be obtained. is there. In addition, when the concentration of polyester resin is less than 10% by mass, the concentration of polyester resin is further decreased in the next phase inversion emulsification step, and a large amount of organic solvent is removed in the solvent removal step. It can become uneconomical as it An apparatus for dissolving polyester resin in an organic solvent may be any apparatus provided with a tank into which a liquid can be introduced and capable of appropriate stirring. The polyester resins used in the dissolving step may be used alone or in combination of two or more.

[0041] As the organic solvent, known ones can be used. For example, ketone organic solvents, aromatic hydrocarbon organic solvents, ether organic solvents, halogen-containing organic solvents, alcohol organic solvents And ester-based organic solvents and glycol-based organic solvents. The organic solvents may be used alone or in combination of two or more, but in order to obtain the aqueous dispersion of the present invention, selection of the organic solvent so as to dissolve 10% by mass or more of polyester resin. It is preferable to use an organic solvent which can be dissolved by 20% by mass or more. An organic solvent which can be dissolved by 30% by mass or more is more preferable. Examples of such organic solvents include acetone, methyl ethyl ketone (2-butanone) (hereinafter referred to as MEK), methyl isopyl ketone (4-methyl-2-pentanone) (hereinafter referred to as Ml BK), dioxane, tetrahydrofuran, cyclopentadiene, etc. Hexanone alone, acetone mixed solution with ethylene glycol monobutyl ether, MEKZ ethylene glycol monobutyl ether mixed solution, mixed solution of ethylene glycol monobutyl ether, mixed solution of ethylene glycol monobutyl ether, mixed solution of ethylene glycol monobutyl ether with tetrahydrofuran, tetrahydrofuran glycol glycol monobutyl ether Mixed solution, mixed solution of cyclohexanone and ethylene glycol monobutyl ether, mixed solution of acetone and isopropanol, mixed solution A propanol mixed solution, a MIBKZ isopropanol mixed solution, a dioxane Z isopropanol mixed solution, a tetrahydrofuran z isopropanol mixed solution, a cyclohexanone z isopropanol mixed solution, and the like can be suitably used.

Next, the phase inversion emulsification step will be described.

In the phase inversion emulsification step, an organic solvent solution of polyester resin is dispersed in water together with the basic compound by phase inversion emulsification. In the present invention, it is preferable to add a basic compound to a polyester resin solution and gradually add water thereto to carry out phase inversion emulsification. If the rate of water addition is fast, it may be difficult to obtain a uniform aqueous dispersion. In the present invention, “phase inversion emulsification” means adding an amount of water exceeding the amount of the organic solvent contained in this solution to the organic solvent solution of polyester resin to obtain a system from an organic solvent phase to an oZw emulsion dispersion system. It means to change it.

The amount of the basic compound used is determined in accordance with the amount of carboxyl groups contained in the polyester resin, and is an amount capable of neutralizing at least a part of the carboxyl groups, ie, force propoxyl group Against 0.4 to 20 times equivalent is preferable 0.4 to 19 times equivalent is more preferable 0.8 to 18 times equivalent is optimum. By setting the amount of the basic compound to be within the above range, it is often possible to obtain a polyester resin aqueous dispersion having particularly good storage stability.

Phase inversion emulsification is preferably performed at 10 to 40 ° C., particularly preferably 15 to 35 ° C. 15 ° C. to 30 ° C. is optimum. By performing phase inversion emulsification at 40 ° C. or less, the volume average particle diameter of the obtained aqueous dispersion tends to be small, and an aqueous dispersion having excellent storage stability can be easily obtained. In addition, the appearance of the polyester resin contained in the aqueous dispersion of the present invention tends to gradually change its solution state even if it is dissolved in an organic solvent, for example, at a low temperature such as 5 ° C. If stored for 10 hours or more, the viscosity of the organic solvent solution of polyester resin may become high or may become cloudy. Thus, the organic solvent solution of polyester resin used in the present invention may have poor dissolution stability at low temperatures, so phase inversion emulsification is preferably 10 ° C. or more, particularly preferably 15 ° C. or more. When phase inversion emulsification is carried out without controlling the dissolution state of the polyester resin in the organic solvent solution, the quality of the obtained aqueous dispersion is not stable, which is not preferable. An apparatus for carrying out the phase inversion emulsification process may be any apparatus provided with a tank into which a liquid can be introduced and capable of appropriate stirring. Such devices include devices known to those skilled in the art as solid Z liquid stirrers and emulsifiers (eg, homomixers).

Next, the solvent removal step will be described.

In the solvent removal step, the organic solvent contained in the aqueous dispersion obtained in the phase inversion emulsification step is distilled, and a part or all of the organic solvent is removed from the aqueous dispersion. This step can be carried out under reduced pressure or under normal pressure. Desolvent under normal pressure is likely to generate aggregates! In such cases, the internal temperature may be adjusted to 70 ° C. or less, preferably 60 ° C. or less, and optimally 50 ° C. or less. The apparatus for carrying out the solvent removal step may be any apparatus provided with a tank into which the liquid can be introduced and capable of appropriate stirring.

Incidentally, after the phase inversion emulsification step, the solvent removal step is carried out to be included in the aqueous dispersion after the phase inversion emulsification step and to contribute to the neutralization of the polyester resin. It is also possible to remove some or all of them.

[0048] According to such a production method, an aqueous dispersion having a uniform state in which the solid concentration locally does not find any difference in solid concentration from other parts, such as precipitation or phase separation in appearance, is obtained. Be

In the production of the aqueous dispersion, a filtration step may be provided in the process for the purpose of removing foreign matter and the like. In such a case, for example, a stainless steel filter (wire diameter: 0.35 mm, plain weave) of about 300 mesh may be installed, and pressure filtration (air pressure: 0.2 MPa) may be performed.

(How to use)

Next, the 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, it can be uniformly coated on the surface of various substrates by a known film forming method, dicing method, brush coating method, spray coating method, curtain flow coating method, etc. By applying the heat treatment, the aqueous medium can be removed, and a uniform resin coating can be formed in close contact with the surface of various substrates. As a heating device at this time, an ordinary hot air circulation type oven, an infrared heater or the like may be used. Further, the heating temperature and the heating time are appropriately selected depending on the type of the base material and the like. However, considering the economy, the heating temperature is optimally 80.degree. To 100.degree. C., preferably 60.degree. To 120.degree. The heating time is preferably 1 second to 30 minutes, more preferably 5 seconds to 20 minutes, and most preferably 10 seconds to 10 minutes.

In the aqueous dispersion of the present invention, a leveling agent, an antifoaming agent, an anti-glare agent, a pigment dispersant, an ultraviolet light absorber, an antifungal agent, and the like can be used as needed within the scope of achieving the object of the present invention. Various agents such as agents and preservatives, pigments or dyes such as titanium oxide, zinc oxide and carbon black, and water-soluble polymers such as polybutyl alcohol and polyethylene oxide may be added. Further, by adding water or an organic solvent, it is possible to adjust the viscosity, adjust the wettability to the substrate, and the like.

Example

The present invention will be specifically described by way of the following examples.

(1) Composition of polyester resin

Oh! ! -Determined from NMR analysis (Varian 300 MHz). Also, no assignable peaks can be found on the NMR ^ vector, and the resin containing the constituent monomers is subjected to methanolysis at 230 ° C. for 3 hours in a sealed tube and then used for gas chromatogram analysis. And quantitative analysis was performed.

(2) Acid value of polyester resin

0.5 g of polyester resin is dissolved in 50 ml of water Z Dioxane = 1 Z 9 (volume ratio) and titrated with KOH using taresol red as an indicator! /, Mg mg of KOH consumed for neutralization is polyester The value converted per 1 _{g of} fat was determined as the acid value.

(3) Melting point and heat of crystal fusion of polyester resin

It is a value measured under the following conditions using a DSC (differential scanning calorific value measurement) device (DSC7 manufactured by Perkin-Elmer Co., Ltd.) as a sample, using 10 mg of polyester resin thermostated at 20 ° C. for one week. That is, the temperature is raised from 50 ° C. to 280 ° C. at a heating rate of 20 ° C. in a nitrogen stream, the peak of the melting temperature at the time of temperature rising is the melting point, and the melting peak area at that time is the heat of melting.

(4) Number average molecular weight of polyester resin

The number average molecular weight is determined by GPC analysis (liquid transfer unit LC-lOADvp type manufactured by Shimadzu Corporation) and And UV-visible spectrophotometer SPD-6AV type, detection wavelength: 254 nm, solvent: tetrahydrofuran, polystyrene conversion).

(5) Solid content concentration

Approximately 1 g of the aqueous dispersion or the organic solvent solution is weighed (Xg), and the mass of the residue (solid content) after drying for 2 hours at 150 ° C. is evaluated (Yg). The solid content concentration was determined by the equation.

Solid content concentration (mass%) = Y / XX 100

(6) Organic solvent content of aqueous dispersion

Shimadzu Corporation gas chromatograph GC-8A [FID detector used, carrier gas: nitrogen, column packing material (manufactured by GL Science): PEG-HT (5%)-UNIPORT HP (60Z80 mesh), column size: diameter 3 mm x length 3 m, sample input temperature (injection temperature): 150 ° C., column temperature: 60 ° C., internal standard substance: n-butanol], diluted aqueous dispersion with water directly in the device The organic solvent content was determined.

(7) Volume average particle diameter of aqueous dispersion

The aqueous dispersion was diluted with water to 0.1%, and the volume average particle size was measured using Nikkiso, MICROTRAC UPA (model 93 40-UPA). 300 nm or less is preferable.

(8) Storage stability of aqueous dispersion

30 ml of the aqueous dispersion was placed in a 50 ml glass sample bottle, and the appearance after storage for 60 days at 25 ° C. was visually observed, and the marks Δ and を were accepted.

○: No change.

Δ: Part of particles settled in the bottom of the sample bottle

X: The viscosity of the aqueous dispersion is high and it is coagulated.

(9) Thickness of resin coating

The thickness of the substrate is measured in advance using a thickness gauge (manufactured by Union Tool Co., Ltd., MICROFINE), and after a resin coating is formed on the substrate using an aqueous dispersion, the resin coating is provided. The thickness of the substrate was measured by the same method, and the difference was taken as the thickness of the resin coating.

(10) Adhesiveness of Resin Coating Using a tabletop coating system (Yasuda Seiki, film applicator No. 542-AB, equipped with a bar coater), the aqueous dispersion is coated on a PET film, and in an oven set at 120 ° C 1 After forming a resin film about 2 m thick on the PET film by heating for 1 minute, two sheets of the resin film-formed PET film are overlapped so that the coated surface is in contact, and the heat press (seal It was pressed at 80 ° C. under a pressure of 0.2 MPa for 10 seconds. If the press temperature is 80 ° C and the film does not melt sufficiently and adhesion is poor (if the peel strength is 0.5 NZ 25 mm or less), the press temperature is 120 ° C and adhesion is poor even at that temperature. It was 160 ° C. This sample is cut out with a width of 25 mm, and after one day, using a tensile tester (Intesco Corporation Intesco Precision Universal Material Testing Machine Model 2020), measure the peel strength of the film at a tensile speed of 5 OmmZ and a tensile angle of 180 degrees. The adhesion was evaluated. Peel strength 3.5 NZ 25 mm or more was judged to be comparable in strength to an organic solvent-soluble adhesive. The peel strength is preferably 5. ONZ 25 mm or more. 7. ONZ 25 mm or more is significantly preferable.

The polyester resins used in the examples and comparative examples were obtained as follows.

[Production example of polyester resin P-1]

A mixture consisting of 1163 g of terephthalic acid, 1412 g of isophthalic acid, 1920 g of cenoic acid and 2740 g of 1,4-butanediol was heated at 220 ° C. for 4 hours in an autoclave to carry out an esterification reaction. Then, after 2.6 g of tetrabutyl titanate as a catalyst was added, the temperature of the system was raised to 230 ° C., and the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, the temperature of the system is lowered, and 47 g of trimellitic acid is added at 220.degree. Stirring was performed for 2 hours to carry out depolymerization reaction. After that, the system was pressurized with nitrogen gas, and the resin was discharged in the form of a sheet. This was cooled to room temperature to obtain a sheet-like polyester resin P-1.

[Production Example of Polyester Resin P-2]

A mixture consisting of 831 g of terephthalic acid, 1578 g of isophthalic acid, 708 g of cenoic acid, 799 g of ε-prolabatone and 2424 g of 1,4-butanediol was heated in an autoclave at 220 ° C. for 4 hours to carry out an esterifying reaction . Then, tetrabutyl titaniume as a catalyst After the addition of 1. 7 g of salt, the temperature of the system was raised to 240 ° C., and the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, the temperature of the system is lowered, 32 g of trimellitic acid is added when it reaches 220.degree. C., and 2 hours at 220.degree. Stirring performed depolymerization reaction. After that, the system was pressurized with nitrogen gas, and the resin was discharged in the form of a sheet. The mixture was cooled to room temperature to obtain a sheet-like polyester resin P-2.

[Production Example of Polyester Resin P-3]

A mixture consisting of 1661 g of terephthalic acid, 3032 g of cenoic acid and 3154 g of 1,4-butanediol was heated in an autoclave at 235 ° C. for 4 hours to carry out an esterifying reaction. Then, after the addition of 2.6 g of tetrabutyl titanate as a catalyst, the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, 183 g of trimellitic anhydride is added while maintaining the system temperature of 235 ° C., and stirring is carried out at 235 ° C. for 2 hours. The depolymerization reaction was carried out. After that, the system was pressurized with nitrogen gas, and the resin was discharged in the form of a sheet. The mixture was cooled to room temperature to obtain sheet-like polyester resin P-3.

[Production Example of Polyester Resin P-4]

A mixture consisting of 1661 g of terephthalic acid, 3032 g of cenoic acid, 2588 g of 1,4 butanediol and 388 g of ethylene glycol was heated in an autoclave at 235 ° C. for 4 hours to carry out an ester reaction. Then, after adding 2.6 g of tetrabutyl titanate as a catalyst, the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polymerization reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, and 38 g of trimellitic anhydride is added while maintaining the system temperature of 235 ° C., and stirring is carried out at 235 ° C. for 2 hours. The reaction was depolymerized. Thereafter, the system was pressurized with nitrogen gas and the resin was discharged in the form of a sheet. The mixture was cooled to room temperature to obtain a sheet-like polyester resin P-4.

[Production Example of Polyester Resin P-5]

A mixture consisting of 2201 g of terephthalic acid, 2375 g of cenoic acid, and 3154 g of 1,4 butane diacetate was heated in an autoclave at 235 ° C. for 4 hours to carry out an esterifying reaction. Then, after adding 2.6 g of tetrabutyl titanate as a catalyst, the pressure of the system is gradually reduced After 5 hours, it was 13Pa. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, 183 g of trimellitic anhydride is added while maintaining the system temperature of 235 ° C., and stirring is carried out at 235 ° C. for 2 hours. The depolymerization reaction was carried out. After that, the system was pressurized with nitrogen gas, and the resin was discharged in the form of a sheet. The mixture was cooled to room temperature to obtain sheet-like polyester resin P-5.

[Production Example of Polyester Resin P—6]

A mixture consisting of 1263 g of cenosyn, 2214 g of f-NOC, 3143 g of 1,4 butane diisocyanate, and 17 g of trimethyone monolepropane was heated in an autoclave at 235 ° C. for 4 hours to carry out an esterase reaction. Then, after adding 2.6 g of tetrabutyltitanate as a catalyst, the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, 149 g of trimellitic anhydride is added while maintaining the system temperature of 235 ° C., and stirring is carried out at 235 ° C. for 2 hours The reaction was depolymerized. Thereafter, the system was pressurized with nitrogen gas and the resin was discharged in the form of a sheet. It was cooled to room temperature to obtain a sheet-like polyester resin P-6.

[Production Example of Polyester Resin P- 7]

A mixture consisting of 2492 g of terephthalic acid, 623 g of isophthalic acid, 1263 g of cenoic acid, 1 1 g of ethylene glycolon 1 131 and 1315 g of neopentyl glycol was heated in an autoclave at 250 ° C. for 4 hours to carry out an esterifying reaction. Then, after adding 3.3 g of zinc acetate dihydrate as a catalyst, the temperature of the system was raised to 270 ° C. and the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, the temperature of the system is lowered, and 29 g of trimellitic anhydride is added at 265.degree. The reaction was stirred for 2 hours to carry out a depolymerization reaction. After that, the system was under nitrogen pressure and the resin was disbursed as a sheet. This was cooled to room temperature to obtain a sheet-like polyester resin P-7.

[Production Example of Polyester Resin P-8]

A mixture consisting of 1163 g of terephthalic acid, 1412 g of isophthalic acid, 1920 g of cenoic acid and 2740 g of 1,4-butanediol was heated at 220 ° C. for 4 hours in an autoclave to carry out an esterification reaction. Then, after adding 2.6 g of tetrabutyl titanate as a catalyst, The temperature of the system was raised to 230 ° C. and the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction was further continued, and after 4 hours, the system was pressurized with nitrogen gas, and the resin was discharged as a sheet. This was cooled to room temperature to obtain a sheet-like polyester resin P-8.

[Production Example of Polyester Resin P-9]

A mixture consisting of 1163 g of terephthalic acid, 1412 g of isophthalic acid, 1920 g of cenoic acid and 2740 g of 1,4-butanediol was heated at 220 ° C. for 4 hours in an autoclave to carry out an esterification reaction. Then, after 2.6 g of tetrabutyl titanate as a catalyst was added, the temperature of the system was raised to 230 ° C., and the pressure of the system was gradually reduced to 13 Pa after 1.5 hours. Under these conditions, the polycondensation reaction is further continued, and after 4 hours, the system is brought to normal pressure with nitrogen gas, the temperature of the system is lowered, and when it reaches 220 ° C, 125 g of isophthalic acid and 105 g of trimellitic acid are added. The reaction mixture was stirred at 220 ° C. for 2 hours for depolymerization reaction. After that, the system was pressurized with nitrogen gas, and the resin was discharged in the form of a sheet. It was cooled to room temperature to obtain sheet-like polyester resin P-9.

The results of analyzing the characteristics of the polyester resin obtained as described above are shown in Table 1.

[table 1]

(Example 1)

[Dissolution process] 400 g of polyester resin P-1 and 600 g of MEK are put into a polyethylene container 21 and a stirrer (made by Tokyo Rika Kikai Co., Ltd., MAZELA NZ) while heating the container with warm water of about 70 ° C. The polyester resin was completely dissolved in MEK by stirring using 1000) to obtain a polyester resin solution having a solid content concentration of 40% by mass.

[Phase inversion emulsification process] Next, the above polyester is added to a jacketed glass container (capacity 21) 500 g of the resin solution was charged, cold water was passed through a jacket, the system temperature was maintained at 18 ° C., and stirring was performed with a stirrer (MAZELA NZ-1000, manufactured by Tokyo Rika Kikai Co., Ltd.) (rotational speed 600 rpm). Then, while stirring, 38 g of triethylamine was added as a basic compound, and then 462 g of distilled water at 18 ° C. was added at a rate of 100 g and 100 g Zmin. While the entire amount of distilled water was added, the temperature inside the system was always below 20 ° C. After completion of the addition of distilled water, the mixture was stirred for 30 minutes to obtain an aqueous dispersion having a solid content concentration of 20% by mass.

[Desolvation process] Next, 800 g of the obtained polyester resin aqueous dispersion is charged into a round bottom flask, a mechanical-cal stirrer and a Liebig cooler are installed, and the flask is heated with an oil bath to obtain aqueous solution under normal pressure. About 284 g of the medium was distilled off. After cooling, the liquid in the flask was filtered with a 600 mesh (tack weave) stainless steel filter, and the solid content concentration of the filtrate was measured to be 31.0% by mass. While stirring this filtrate, distilled water was added to adjust the solid content concentration.

Solid concentration: 30% by mass

Content rate of organic solvent: 0.03 mass%

Volume average particle diameter: 129 nm

(Example 2)

[Dissolution process] 300 g of polyester resin P-2 and 70 Og of MEK are put into a polyethylene container of 21 and a stirrer (made by Tokyo Rika Kikai Co., Ltd., MAZELA NZ) while heating the container with warm water of about 70 ° C. The polyester resin was completely dissolved in MEK by stirring using 1000) to obtain a polyester resin solution having a solid concentration of 30% by mass.

[Phase inversion emulsification process] Next, 500 g of the polyester resin solution was charged in a jacketed glass container (capacity 21), cold water was passed through the jacket and the system temperature was maintained at 18 ° C, and a stirrer (manufactured by Tokyo Rika Kikai Co., Ltd.) The mixture was stirred with MAZELA NZ-1000) (rotational speed 600 rpm). Next, with stirring, 29 g of triethylamine was added as a basic compound, and then 471 g of distilled water at 18 ° C. was added at a rate of 100 g Zmin. While the entire amount of distilled water was added, the temperature inside the system was always below 20 ° C. After completion of the addition of distilled water, the mixture was stirred for 30 minutes to obtain an aqueous dispersion having a solid content concentration of 15% by mass.

[Solvent removal step] Round bottom flask with 800 g of the polyester resin aqueous dispersion obtained in the following manner. The flask was heated in an oil bath, and about 338 g of the aqueous medium was distilled off under atmospheric pressure. After cooling, the liquid in the flask was filtered with a 600 mesh (tack weave) stainless steel filter, and the solid content concentration of the filtrate was measured to be 26% by mass. While stirring this filtrate, distilled water was added to adjust the solid content concentration.

Solid concentration: 25% by mass

Organic solvent content: 0.2% by mass

Volume average particle size: 11 lnm

(Example 3)

[Dissolution process] 300 g of polyester resin P-3 and 70 Og of MEK are put into a polyethylene container of 21 and a stirrer (made by Tokyo Rika Kikai Co., Ltd., MAZELA NZ) while heating the container with warm water of about 70 ° C. The polyester resin was completely dissolved in MEK by stirring using 1000) to obtain a polyester resin solution having a solid concentration of 30% by mass.

[Phase inversion emulsification process] Next, 500 g of the polyester resin solution was charged in a jacketed glass container (capacity 21), cold water was passed through the jacket and the system temperature was maintained at 28 ° C., and a stirrer (manufactured by Tokyo Rika Kikai Co., Ltd.) The mixture was stirred with MAZELA NZ-1000) (rotational speed 600 rpm). Next, 37 g of 28% by mass ammonia water was added as a basic compound while stirring, and subsequently 463 g of distilled water at 25 ° C. was added at a rate of 100 g Zmin. The system temperature was always below 30 ° C. during the total addition of distilled water. After completion of the addition of distilled water, the mixture was stirred for 30 minutes to obtain an aqueous dispersion having a solid content concentration of 15% by mass.

[Desolvation process] Next, 800 g of the obtained polyester resin aqueous dispersion is charged into a round bottom flask, a mechanical-cal stirrer and a Liebig cooler are installed, and the flask is heated with an oil bath to obtain aqueous solution under normal pressure. About 387 g of the medium was distilled off. After cooling, the liquid in the flask was filtered with a 600 mesh (tack weave) stainless steel filter, and the solid concentration of the filtrate was measured to be 31% by mass. While stirring this filtrate, distilled water was added to adjust the solid content concentration.

Solid concentration: 30% by mass

Organic solvent content: 0.01 mass% Volume average particle diameter: 196 nm

Example 4

Example 1 and Example 1 except that the polyester resin is changed to P-4, 32 g of triethylamine is added as a basic compound and the distilled water added in the phase inversion emulsification step is changed to 468 g. The same operation was performed to obtain an aqueous dispersion.

Solid concentration: 30% by mass

Content rate of organic solvent: 0.03 mass%

Volume average particle diameter: 147 nm

Example 5

In the phase inversion emulsification process, while the system temperature is kept at 5 ° C, triethylamine and distilled water at 5 ° C are added to the polyester resin solution that has begun to become cloudy, and while the total amount of distilled water is added, the system temperature is An aqueous dispersion was obtained by the same operation as in Example 1 except that the temperature was always kept at 7 ° C. or less. Solid concentration: 30% by mass

Content rate of organic solvent: 0.03 mass%

Volume average particle size: 319 nm

Comparative Example 1

Polyester resin is changed to P-5, 39 g of 28% by mass ammonia water is added as a basic compound, and distilled water added in the phase inversion emulsification process is changed to 461 g. The same procedure as in Example 3 was carried out to obtain an aqueous dispersion.

Solid concentration: 30% by mass

Organic solvent content: 0.01 mass%

Volume average particle size: 202 nm

(Comparative Example 2)

Except changing polyester resin to P-6 and adding 39 g of 28% by mass ammonia water as a basic compound and changing to 477 g distilled water added in the phase inversion emulsification process. The same procedure as in Example 3 was carried out to obtain an aqueous dispersion.

Solid concentration: 30% by mass Organic solvent content: 0.01 mass%

Volume average particle size: 236 nm

(Comparative Example 3)

Same as Example 1 except that polyester resin is changed to P-7, 13 g of trytilamine is added as a basic compound, and distilled water added in the phase inversion emulsification step is changed to 487 g. To obtain an aqueous dispersion.

Solid concentration: 30% by mass

Content rate of organic solvent: 0.03 mass%

Volume average particle size: 14 lnm

(Comparative Example 4)

Example 1 and Example 1 except that polyester resin is changed to P-8, 3 g of triethylamine is added as a basic compound, and distilled water added in the phase inversion emulsification step is changed to 497 g. The same operation was performed, but the polyester resin was entangled with the stirring blade during addition of distilled water, and a uniform aqueous dispersion was not obtained.

(Comparative Example 5)

Same as Example 1, except that polyester resin is changed to P-9, and 23 g of trytilamine is added as a basic compound, and distilled water added in the phase inversion emulsification step is changed to 477 g. To obtain an aqueous dispersion.

Solid concentration: 30% by mass

Content rate of organic solvent: 0.03 mass%

Volume average particle size: 136 nm

Table 2 shows the polyester resin used in Examples and Comparative Examples, solid concentration of organic solvent solution, phase inversion temperature, and total carboxyl group of polyester resin of used basic compound. The measurement results of equivalent ratio to molar amount, solid content concentration of the obtained aqueous dispersion, organic solvent content, volume average particle diameter, storage stability, and press temperature and peel strength of the obtained film are shown.

[Table 2]

From the examples and comparative examples, it is understood that the resin film formed from the aqueous dispersion of polyester resin of the present invention is excellent in adhesion. In Example 5, the temperature in the system in the phase inversion process Since the degree was lower than the preferred range of the present invention, the organic solvent solution of polyester resin became cloudy, and the volume average particle diameter of the obtained aqueous dispersion became large. Therefore, the storage stability was not good.

[0086] Comparative Example 1 had higher strength than the range of the present invention of the melting point of the polyester resin to be used, so the adhesion was poor at press temperatures of 80 ° C and 120 ° C. By raising the press temperature to 160 ° C., the PET film of the bonded force substrate shrank.

In Comparative Example 2, since the heat of crystal fusion exceeded the range of the present invention, the aqueous dispersion obtained was inferior in storage stability.

In Comparative Example 3, since the heat of crystal melting of the polyester resin used falls below the range of the present invention, a film excellent in adhesiveness was not obtained.

In Comparative Example 4, an aqueous dispersion was not obtained because the acid value of the polyester resin used was lower than the range of the present invention.

In Comparative Example 5, since the number average molecular weight at which the acid value of the polyester resin used is higher than the range of the present invention is out of the range of the present invention, a film excellent in adhesion was not obtained. Industrial applicability

The polyester resin aqueous dispersion of the present invention is useful for forming a film, and it is useful, for example, as an anchor coating agent for steel plate or film, an adhesive for paper or film, a binder component of paint or ink, paper or film. It is particularly useful as a coating agent.

The polyester resin aqueous dispersion of the invention is also excellent in storage stability.

Claims

The scope of the claims

[1] An aqueous polyester resin dispersion comprising a polyester resin having a melting point of 100 ° C. or less, a heat of crystal fusion of 2 to 12 jZg, an acid value of 2 to 30 mg KOHZg, and a number average molecular weight of 5000 or more. .

[2] A feature is that the polyester resin contains 30 to 70% by mole of aromatic dicarboxylic acid with respect to the total acid component and 70 to 100% by mole of aliphatic glycol based on the total alcohol component as components. The polyester resin aqueous dispersion according to claim 1.

[3] As the polyester榭脂configuration components, contain one, 4-butanediol 70-100 mole ^_0/0 for terephthalic Le acids and total alcohol component 15 to 50 mol% relative to the total acid component The polyester resin aqueous dispersion according to claim 2, characterized in that

[4] The polyester resin aqueous dispersion according to claim 2 or 3, wherein the polyester resin further comprises an aliphatic dicarboxylic acid and Z or an aliphatic ratatone.

[5] A method for producing a polyester resin aqueous dispersion by dispersing an organic solvent solution of polyester resin together with a basic binder in water by phase inversion emulsification, wherein phase inversion is carried out at 10 to 40 ° C. The method for producing a polyester resin aqueous dispersion according to any one of claims 1 to 4, which comprises emulsifying.