JPH1160659A - Preparation of aqueous dispersion of reactive resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an industrially advantageous method for the preparation of an aqueous dispersion of a reactive resin which is excellent in storage stability, colorlessness, operability and hardenability and to obtain a composition which gives an aqueous dispersion of a reactive resin which exhibits an excellent performance especially in the application for an overprint vanish and an ink. SOLUTION: A polymer containing (meth)acryloyl groups and carboxylic groups having an acid value of 50-500 and a number average molecular weight of 1,000-15,000 is obtained by a continuous polymerization of one or more kinds of a (meth)acrylate containing carboxylic groups or one or more kinds of this (meth)acrylate and a monomer containing an ethylene type unsaturated group, at 150-310 deg.C as the polymerization temperature. An reactive resin having an acid value of 20-150 is obtained by an addition reaction of the polymer with a (meth)acrylate containing epoxy groups in an reactive thinner into which the polymer is soluble. An aqueous dispersion of a reactive resin is obtained by dispersing a reacted mixture containing the reactive resin into an alkaline aqueous medium.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an aqueous dispersion of a reactive resin which can be cured by irradiation with an active energy ray such as an electron beam or ultraviolet ray, or at room temperature or by heating. The reactive resin aqueous dispersion to be used is paint, overprint varnish (hereinafter referred to as OP).
V), printing inks, adhesives, fillers, molding materials, resists, etc., and particularly useful as OPVs and inks, and can be awarded in the technical field using them. In this specification, acrylate and / or methacrylate are referred to as (meth) acrylate,
Acrylic acid and / or methacrylic acid are referred to as (meth) acrylic acid. The unit of the acid value is mgKOH / g.

[0002]

2. Description of the Related Art In recent years, air pollution on a global scale due to the release of organic solvents, cleaning agents, and the like used in various industries and the like into the atmosphere has been progressing, and there is a concern about the effects on living organisms.
For this reason, in compositions used for applications such as various paints, inks and adhesives, studies have been made on solvent-free compositions and aqueous compositions containing no organic solvent.

[0003] As one of methods for making a reactive resin, which is a raw material for the above uses, an aqueous solution, a polymer having a carboxyl group is subjected to an addition reaction with a compound having an epoxy group and an unsaturated group, and the polymer is reacted with a reactive group. By introducing a certain unsaturated group, to produce a reactive resin having a carboxyl group and an unsaturated group,
There is a method of neutralizing the resin with an alkali and suspending or emulsifying the resin in water or an aqueous solution containing an organic solvent such as an alcohol using an emulsifier in some cases (hereinafter referred to as a method A, JP-A-51-17922). No. 51-23531
issue). As another method, in the presence of a surfactant,
There is also a method in which a polymer having a carboxyl group is produced in water, and a compound having an epoxy group and an unsaturated group is subjected to an addition reaction to the obtained polymer (hereinafter referred to as a method B, see Japanese Patent Application Laid-Open No.
No. 211950).

[0004] Solventless active energy ray-curable compositions for use in OPVs and inks include those comprising oligoester (meth) acrylates such as polyester acrylate, epoxy acrylate and urethane acrylate and a reactive diluent. It has been known. For example, as an example of OPV, JP-A-3-292371 discloses a composition comprising a polymerizable acrylate having a specific structure and a thermoplastic resin having a specific softening point. Examples of the ink composition include JP-A-50-5
No. 6423 discloses a composition containing an oligopoly (meth) acrylate having a specific structure. JP-A-8-34948 discloses a composition comprising a reaction product of a specific compound and (meth) acrylic acid.

On the other hand, as an example of an aqueous active energy ray-curable composition for OPV and ink applications, a composition in which a resin is suspended or emulsified in water is applied to the surface of a substrate,
Thereafter, a method of obtaining a dried coating film by a method such as heating is known (Japanese Patent Application Laid-Open Nos. 51-17922 and 51-23).
531 and JP-A-6-212950).

[0006]

In the study of aqueous conversion of a reactive resin, in the case of the above-mentioned method A, the reaction of adding a compound having an epoxy group and an unsaturated group to a polymer having a carboxyl group has a property of imparting hydrophilicity. It is carried out in a solvent such as alcohol or ketone. In this case, when the obtained reactive resin is made aqueous, not only the operation of removing the solvent contained therein by evaporation or the like is necessary, but also it is difficult to completely remove the solvent from the reactive resin. Therefore, the product may have an odor, and it takes a long time to remove the solvent as much as possible.As a result, the reactive resin becomes an anaerobic atmosphere which promotes the curing reaction. For a long time, the storage stability of the final product may be deteriorated, or the product may be colored. or,
In the case of Method B, the resulting aqueous dispersion of the reactive resin contains a surfactant in the liquid, so that the cured film of the reactive resin has poor water resistance.

Further, the above-mentioned conventional solvent-free type active energy ray-curable OPV composition has insufficient adhesion (adhesion) of the cured film to a base material such as paper or printing ink. Similarly, the solvent-free active energy ray-curable ink composition also had insufficient adhesion to the substrate. The reasons for such insufficient adhesion are:
In an OPV composition other than the active energy ray-curable composition and a composition containing a solvent-dried resin composition or a thermosetting resin used as an ink composition, the strain is gradually distorted due to heat drying or thermosetting. On the other hand, in the active energy ray-curable composition, the time required for curing is short, and stress strain caused by volume shrinkage during curing is easily accumulated in the cured film. In the solvent-free active energy ray-curable composition, in order to improve the adhesion, non-reactive substances such as acrylic polymer, polyester and petroleum resin are mixed and dissolved in the composition,
Although a method of lowering the volume shrinkage during curing is also known, there is a problem that the curability of the composition or the solvent resistance of the cured product is reduced by the addition of these non-reactive substances. . Furthermore, since such solventless compositions are generally high in viscosity, workability at the time of production of the composition and at the time of application of the composition is often poor.

Further, the conventional aqueous active energy ray-curable composition for OPV and ink has insufficient solvent resistance and water resistance of the cured film, and also has poor surface gloss and adhesion to a substrate. In addition, the hardness of the cured film was insufficient in ink applications, and the water resistance was apt to be insufficient due to the water-based composition in all applications.

The present inventors have found that the products have excellent storage stability,
An industrially advantageous method for producing an aqueous dispersion of a reactive resin having no coloring and excellent workability and curability, and the obtained aqueous dispersion of a reactive resin exhibits excellent performance especially for OPV and ink applications. Intensive study was conducted to find a suitable composition.

[0010]

Means for Solving the Problems The present inventors have conducted intensive studies in order to solve the above-mentioned problems, and as a result, the acid value obtained by high-temperature continuous polymerization is 50 to 500, and the number average molecular weight is 1,000 to 1,000. A polymer having 15,000 (meth) acryloyl groups and carboxyl groups is used as a raw material polymer, and a polymer having an epoxy group to the polymer is used.
The present inventors have found that it is effective to carry out the acrylate addition reaction in a reactive diluent, and to make the resulting reaction mixture aqueous, thereby completing the present invention. Hereinafter, the present invention will be described in detail.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

○ Polymer having (meth) acryloyl group and carboxyl group In the production method of the present invention, the polymer serving as the skeleton of the reactive resin is a (meth) acrylate having a carboxyl group (hereinafter referred to as a carboxyl group-containing (meth) acrylate). Or the (meth) acrylate and at least one other monomer having one ethylenically unsaturated group (hereinafter referred to as an ethylenically unsaturated monomer) under specific conditions. A polymer having a (meth) acryloyl group and a carboxyl group (hereinafter simply referred to as a carboxyl group-containing polymer) obtained by polymerization below is used.

Various carboxyl group-containing (meth) acrylates can be used. For example, a Michael addition reaction of an unsaturated carboxylic acid such as (meth) acrylic acid, crotonic acid, cinnamic acid or (meth) acrylic acid can be used. Oligomers such as ω-carboxypolycaprolactone mono (meth) acrylate, monohydroxyethyl phthalate (meth) acrylate and monohydroxyethyl succinate (meth) acrylate.

The carboxyl group-containing polymer may be a homopolymer or a copolymer of a carboxyl group-containing (meth) acrylate, or may be a copolymer of the carboxyl group-containing (meth) acrylate and an ethylenically unsaturated monomer. It may be a polymer. As the ethylenically unsaturated monomer, various ones other than the above-mentioned carboxyl group-containing (meth) acrylate can be used. For example, styrene, α-methylstyrene, (meth) acrylonitrile, vinyl acetate, and (meth) Acrylate and the like. Specific examples of (meth) acrylate include alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, and 2-ethylhexyl (meth) acrylate, and cyclohexyl. Alicyclic alkyl (meth) acrylates such as (meth) acrylate, substituted aryl (meth) acrylates such as benzyl (meth) acrylate, and alkoxyalkyls such as 2-methoxyethyl (meth) acrylate and 2-ethoxyethyl (meth) acrylate Examples include (meth) acrylate, isobornyl (meth) acrylate, and hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate and hydroxypropyl (meth) acrylate.

The copolymerization ratio of the carboxyl group-containing (meth) acrylate and the ethylenically unsaturated monomer is determined on condition that the acid value of the resulting carboxyl group-containing polymer is a value satisfying the following acid value. Is optional.

The carboxyl group-containing polymer used in the present invention must have an acid value of 50 to 500, preferably 100 to 300. If the acid value is less than 50, the aqueous dispersion of the reactive resin finally obtained is inferior in storage stability and, as a result, the concentration of the (meth) acryloyl group introduced into the reactive resin is reduced. Not only does the curability of the obtained reactive resin decrease, but also the hardness and abrasion resistance of the coating film become insufficient. On the other hand, if the acid value exceeds 500, the carboxyl group-containing polymer becomes difficult to dissolve in the reactive diluent, and the finally obtained reactive resin aqueous dispersion becomes difficult to handle due to its high viscosity, In order to adjust the acid value of the resin to a desirable value described below, it is necessary to add a large amount of (meth) acrylate having an epoxy group, and as a result, the hydroxyl value of the reactive resin becomes high due to the hydroxyl group generated by the addition reaction. It becomes the water resistance of the coating,
Inferior in alkali resistance.

The number average molecular weight of the carboxyl group-containing polymer must be 1,000 to 15,000, preferably 2,000 to 10,000. If this value is 1,
If it is smaller than 000, the resulting reactive resin will have poor adhesion and adhesion to the substrate, and the strength of the coating film will be insufficient. On the other hand, this value is 15,0
In the case where it exceeds 00, in the addition reaction of the epoxy group-containing (meth) acrylate in the reactive diluent described below,
The carboxyl group-containing polymer becomes difficult to dissolve in the reactive diluent. Here, if the concentration of the carboxyl group-containing polymer in the reactive diluent is reduced, it is possible to improve the solubility to some extent, but in this case, the obtained reactive resin aqueous dispersion has an adhesiveness or The film strength becomes inferior. In the present invention, it is preferable to use a copolymer having a polydispersity (Mw / Mn) of 3 or less, which is a ratio of a weight average molecular weight (Mw) to a number average molecular weight (Mn) of the copolymer, More preferably, it is 2.5 or less.
A carboxyl group-containing polymer having a polydispersity in this range is excellent in solubility in a reactive diluent, and has a too high viscosity during an addition reaction, resulting in poor stirring or difficulty in handling. I have. In the present invention, the number average molecular weight and the weight average molecular weight are values obtained by using tetrahydrofuran as a solvent and converting the molecular weight measured by gel permeation chromatography (hereinafter abbreviated as GPC) based on the molecular weight of polystyrene. is there.

In the present invention, as the carboxyl group-containing polymer, a carboxyl group-containing (meth) acrylate or the (meth) acrylate and an ethylenically unsaturated monomer are subjected to high-temperature continuous polymerization at a polymerization temperature of 150 to 310 ° C. Use what you have done. According to this high-temperature continuous polymerization method, it is possible to obtain a polymer having a lower polydispersity than that obtained by conventional solution polymerization, and it is not necessary to use a thermal polymerization initiator or use a thermal polymerization initiator. Even in this case, since a carboxyl group-containing polymer having a target molecular weight can be obtained with a small amount of use, a highly pure carboxyl group-containing polymer containing almost no impurities that generate radical species by heat or light can be obtained. The addition reaction between the carboxyl group-containing polymer and the epoxy group-containing (meth) acrylate described in the above can be performed stably, and the finally obtained reactive resin aqueous dispersion has excellent storage stability. It has excellent weather resistance.

Some proposals have already been made for a high-temperature continuous polymerization method, for example, Japanese Patent Application Laid-Open No. 57-502171.
And the known methods disclosed in JP-A-59-6207 and JP-A-60-215007. For example, after filling a pressurizable reactor with a solvent and setting a predetermined temperature under pressure, a carboxyl group-containing (meth) acrylate, the (meth) acrylate and an ethylenically unsaturated monomer, or an Accordingly, there is a method in which a monomer mixture comprising a polymerization solvent is supplied to the reactor at a constant supply rate, and an amount of the reaction solution corresponding to the supply amount of the monomer mixture is withdrawn.
When a polymerization solvent is used, the solvent charged into the reactor at the start of the reaction and the polymerization solvent mixed with the monomer mixture may be the same or different. As the solvent or polymerization solvent, aliphatic hydrocarbons, aromatic hydrocarbons such as toluene, xylene, cumene and ethylbenzene, cellosolves such as butyl cellosolve and glycol ethers such as carbitol, glymes such as ethylene glycol dimethyl ether and diglymes such as diethylene glycol dimethyl ether Such as ethers, ethyl acetate, butyl acetate, cellosolve acetate, methyl propylene glycol acetate, carbitol acetate and ethyl carbitol acetate, etc., ketones such as acetone and methyl ethyl ketone, hexanol, decanol, ethylene glycol, propylene glycol and butylene glycol Such as aliphatic alcohols, aromatic alcohols such as benzyl alcohol and toluene alcohol, and Ethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, can be used polyalkylene glycols such as tetramethylene glycol and polytetramethylene glycol. The usage ratio of the polymerization solvent is preferably 200 parts by weight or less based on 100 parts by weight of the monomer mixture. Also, the monomer mixture, if necessary, can be mixed with a thermal polymerization initiator, the thermal polymerization initiator that can be used in this case is not particularly limited,
Examples include an azonitrile initiator and a peroxide-based initiator. Azonitrile-based initiators include 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile) and 2,2′-azobis (2,4-dimethylvaleronitrile) And the like. Examples of the peroxide-based initiator include hydrogen peroxide, di-t-butyl peroxide and benzoyl peroxide. When the thermal polymerization initiator is blended with the monomer mixture, the amount is preferably 0.001 to 5 parts by weight based on 100 parts by weight of the monomer mixture.

[0019] The reaction temperature must be between 150 and 310 ° C. If the temperature is lower than 150 ° C., there are problems such as the molecular weight of the obtained polymer being too large and the reaction rate being slow. The liquid is colored, the addition reaction described later becomes unstable, and the obtained reactive resin becomes unstable. The pressure does not affect the reaction and depends on the reaction temperature and the boiling point of the monomer mixture and the solvent to be used. Any pressure may be used as long as the reaction temperature can be maintained. The residence time of the monomer mixture is preferably 2 to 60 minutes. When the residence time is less than 2 minutes, the amount of unreacted monomers increases, and the yield of the carboxyl group-containing polymer may decrease. On the other hand, when the residence time exceeds 60 minutes, the productivity may be reduced. Causes a decline.

○ Reactive diluent In the present invention, a (meth) acrylate having one or more epoxy groups is added to the carboxyl group-containing polymer in a reactive diluent. That is, a reactive diluent is used as a reaction solvent for the addition reaction. Various reactive diluents can be used as long as the carboxyl group-containing polymer can be dissolved. In the present invention, in order to disperse the addition reaction mixture in an alkaline aqueous medium, it is preferable to use a reactive diluent having an excellent affinity for water. As a more preferable specific example, (meth) Examples include acrylates, mono- or di (meth) acrylates of alkylene glycols, and mono- or poly (meth) acrylates of alkylene oxide adducts of polyols. Examples of the (meth) acrylate of alkoxyalkylene glycol include methoxyethylene glycol mono (meth) acrylate and ethoxyethylene glycol mono (meth) acrylate. Examples of the alkylene glycol mono- or di (meth) acrylate include ethylene glycol mono- or di (meth) acrylate and propylene glycol mono- or di (meth) acrylate. In mono- or poly (meth) acrylates of alkylene oxide adducts of polyols, polyols include alkylene glycols such as ethylene glycol and propylene glycol, triols such as trimethylolethane, trimethylolpropane and glycerin, pentaerythritol and dipentaerythritol. Of 4
A polyol having at least two hydroxyl groups is exemplified. Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide. As the addition mole number of the alkylene oxide,
1 to 10 mol is preferred. If the number of added moles of the alkylene oxide exceeds 10 moles, the water resistance of the cured film of the obtained reactive resin may be insufficient. The (meta)
Specific examples of acrylates include diethylene glycol mono or di (meth) acrylate, tetraethylene glycol mono or di (meth) acrylate, dipropylene glycol mono or di (meth) acrylate, and tripropylene glycol mono or di (meth) acrylate. Polyalkylene glycol mono- or di (meth) acrylates, and trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth)
Modified ethylene oxide or propylene oxide such as acrylate, pentaerythritol tetra (meth) acrylate and dipentaerythritol hexaacrylate. These reactive diluents may be used in combination of two or more. Furthermore, alkyl (meth) acrylates such as methyl (meth) acrylate, ethyl (meth) acrylate, and propyl (meth) acrylate, and trimethylolpropane, as long as they do not adversely affect the finally obtained reactive resin aqueous dispersion. Tri (meth) acrylate, pentaerythritol tri (meth)
Reactive diluents such as acrylate, pentaerythritol tetra (meth) acrylate and dipentaerythritol hexaacrylate can also be mixed.

Method for Producing Reactive Aqueous Resin Dispersion The production method of the present invention relates to a method for preparing an epoxy group having a (meth) acrylate having an epoxy group (hereinafter referred to as an epoxy group-containing (meth) acrylate) in a reactive diluent. In this method, an addition reaction is performed on a carboxyl group of a polymer, and the addition reaction mixture is dispersed in an alkaline aqueous medium.

Examples of the epoxy group-containing (meth) acrylate include (meth) acrylates having one epoxy group such as glycidyl (meth) acrylate and (meth) acryloxymethylcyclohexene oxide.
It is preferable because the content ratio of (meth) acryloyl group in the obtained reactive resin becomes high and the reactivity becomes excellent.

In the present invention, the addition reaction of the epoxy group-containing (meth) acrylate to the carboxyl group-containing polymer is carried out in a reactive diluent rather than in a usual organic solvent. There is no need to remove it, so that the finally obtained reactive resin aqueous dispersion has no problems such as odor and coloring.

As a method of adding an epoxy group-containing (meth) acrylate to a carboxyl group-containing polymer in a reactive diluent, the carboxyl group-containing polymer is dissolved in the reactive diluent, and then the epoxy group-containing (meth) acrylate is dissolved. A method of adding (meth) acrylate to the solution and stirring with heating. The proportion of the reactive diluent used in the addition reaction is
20 parts by weight per 100 parts by weight of the obtained reactive resin aqueous dispersion.
An amount of up to 80% by weight is preferred. If this proportion is less than 20% by weight, the viscosity of the reaction mixture of the addition reaction will increase, making it difficult to control the addition reaction. It may be difficult to disperse in water, or the stability of the reactive resin aqueous dispersion may be reduced. Examples of a method for dissolving the carboxyl group-containing polymer in the reactive diluent include a method in which the carboxyl group-containing polymer is added to the reactive diluent while stirring and, if necessary, heating. The reaction temperature of the addition reaction is preferably from 60C to 140C. When the reaction temperature is lower than 60 ° C., the reactivity of the addition reaction is inferior, so that the reaction time becomes longer. When the temperature is higher than 140 ° C., the polymerization reaction of the (meth) acryloyl group in the carboxyl group-containing polymer or the reactive resin may occur, or the heat of the reaction may rapidly generate heat. The reaction storage stability of the resulting aqueous dispersion of the reactive resin is deteriorated or coloring occurs.

In the addition reaction, it is preferable to add a catalyst in order to carry out the reaction smoothly. Examples of such catalysts include N, N-dimethylbenzylamine and N, N.
High molecular weight tertiary amines such as N-dimethylaniline; quaternary ammonium salts such as tetradiethylammonium chloride, tetrabutylammonium bromide and benzyltrimethylammonium chloride; hydrochlorides of secondary amines such as diethylammonium chloride; and triphenylphosphine And the like. The preferable addition amount of these catalysts is 0.1 to 10% by weight, more preferably 0.1 to 5% by weight, based on the total amount of the carboxyl group-containing polymer and the epoxy group-containing (meth) acrylate in the reaction solution. % By weight.

In the addition reaction, it is preferable to add a polymerization inhibitor such as hydroquinone and hydroquinone monomethyl ether or to blow in molecular oxygen in order to stably perform the reaction. When a polymerization inhibitor is used, the amount is preferably 10 wtppm to 2% by weight based on the reaction solution.

The reaction ratio of the epoxy group-containing (meth) acrylate to the carboxyl group in the carboxyl group-containing polymer is such that the acid value of the reactive resin after the addition reaction is 20 to 1
The ratio is 50. If the acid value of the reactive resin after the addition reaction is less than 20, the dispersibility of the reactive resin in the obtained aqueous dispersion becomes insufficient, and the resin is agglomerated,
Settles. On the other hand, if the acid value exceeds 150, the produced reactive resin is dissolved without dispersing in water, and the resulting aqueous dispersion of the reactive resin has a high viscosity and is difficult to handle. When the viscosity of the reactive resin aqueous dispersion is increased, there is also a method of lowering the viscosity by adding water to reduce the solid content in the aqueous dispersion, but the aqueous dispersion has insufficient drying properties. turn into.

As a method for dispersing the addition reaction mixture in an alkaline aqueous medium, an alkali component and water or water in which an alkali component is dissolved are added to the reaction mixture.
A method of adding under stirring and the like can be mentioned. As the alkali component in this case, ammonia, an organic amine, an inorganic base, or the like can be used. Among them, ammonia or a low molecular weight organic amine can be used, and the obtained reactive resin aqueous dispersion is applied to a substrate. Then, when dried, it is evaporated and scattered from the coating film, and the finally obtained coating film has excellent water resistance, which is preferable. As low molecular weight organic amines,
And trialkylamines such as trimethylamine, triethylamine and tributylamine, and hydroxyalkylamines such as N, N-dimethylethanolamine, N-methyldiethanolamine and triethanolamine.

The concentration of the alkali component in the alkaline aqueous medium is preferably such that the alkali component accounts for 30 to 100 mol% based on the total amount of carboxyl groups in the carboxyl group-containing polymer. When this ratio is less than 30 mol%, the carboxyl group-containing polymer may be difficult to dissolve or disperse in an aqueous medium, while when it exceeds 100 mol%, the resulting reactive resin aqueous dispersion may be difficult to dissolve or disperse. The odor of ammonia or amine used as an alkali component may remain.

Method of Use The aqueous dispersion of a reactive resin obtained by the present invention can be cured by irradiation with an active energy ray such as an electron beam or ultraviolet ray, or at room temperature or by heating. And in the form of a composition, paint, O
It can be used for various applications such as PV, printing ink, adhesive, filler, molding material and resist. The reactive resin aqueous dispersion obtained in the present invention is particularly suitable for OPV and ink applications. The method of irradiating the active energy ray and the method of heating for curing the reactive resin may be a general method known as a method of curing a radical polymerizable compound.

Other components that can be added to the aqueous dispersion of the reactive resin as required include fillers such as barium sulfate, silicon oxide, talc, clay and calcium carbonate, phthalocyanine blue, phthalocyanine green, Coloring pigments such as titanium and carbon black, various additives such as adhesion-imparting agents and leveling agents, and polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, phenothiazine and N-nitrosophenylhydroxylamine aluminum salt. . The mixing ratio of the other components is preferably 100 parts by weight or less based on 100 parts by weight of the reactive resin. When the polymerization inhibitor is compounded, the compounding ratio is preferably from 10 wtppm to 2% by weight in the composition.

When curing by irradiation with ultraviolet rays as active energy rays, a photopolymerization initiator is added to the aqueous dispersion. When curing by electron beam, it is not necessary to mix a photopolymerization initiator. When curing by irradiation with ultraviolet rays, a general photopolymerization initiator can be used. As the photopolymerization initiator, a water-soluble or hydrophilic photopolymerization initiator is preferable, and specifically, Darocure 295
9, 1173, 1116, Irgacure 184 (all manufactured by Ciba Specialty Chemicals), Kantacure ABQ, BTC and QTX (all manufactured by Shell Chemical)
And the like. In addition, benzoin, benzoin methyl ether, benzophenone, benzyldimethyl ketal, 2,4-dimethylthioxanthone, and the like, which are usually used in a solvent system or a non-solvent system, can also be used. or,
Two or more photopolymerization initiators can be used as needed. The photopolymerization initiator is used in an amount of 0.1 to 1 in the aqueous dispersion.
It is preferable to add 0% by weight. The photopolymerization initiator may be added after the addition reaction or after the aqueous dispersion. When a photopolymerization initiator which is solid and has particularly low solubility in water is used, it is preferable to add the photopolymerization initiator after the addition reaction because the photopolymerization initiator is easily dissolved in water. Before curing,
It is preferable that water as a dispersion medium and ammonia or an organic amine as a preferable neutralizing agent be evaporated and scattered by heating. If moisture remains in the cured coating film, the film strength may be insufficient or the transparency of the film may be impaired.

O Active Energy Beam Curable OPV Composition The aqueous dispersion of a reactive resin obtained in the present invention is particularly useful as an OPV composition. In this case, it is necessary to use, as the reactive diluent, a mono- or poly (meth) acrylate of 1 to 10 mol adduct of polyol alkylene oxide. If the number of alkylene glycol units exceeds 10, the resulting composition will have poor water resistance, and will be unsatisfactory in the use of the OPV composition. In this case, as the target substrate, in addition to plain paper containing cellulose as a main component, for example, films or sheets of polyethylene, polyvinyl chloride, polypropylene, polyester, polycarbonate and polyimide, or paper treated with them, Further, there may be mentioned those in which the surface of these substrates is printed with various inks.

As a method for applying the OPV composition of the present invention to these substrates, a conventionally known method such as direct coating or printing may be used. Then, preferably after removing water, the composition can be cured by irradiating with active energy rays. When the composition is directly applied, a method such as curtain flow coating and roll coating may be used. Furthermore, since the aqueous dispersion of the reactive resin obtained in the present invention has a low viscosity, it is also possible to perform direct coating by spray coating. When applying by printing, a normal printing method such as an offset method, a gravure offset method, a gravure method, and a flexo method can be used. The coating thickness at this time is usually such that the thickness of the cured film after ultraviolet curing is 1 to 20 μm, preferably 1 to 5 μm.

活性 Active energy ray-curable ink composition The aqueous dispersion of a reactive resin obtained in the present invention is particularly useful as an ink composition. In this case, it is necessary to use, as the reactive diluent, a mono- or poly (meth) acrylate of 1 to 10 mol adduct of polyol alkylene oxide. If the number of alkylene glycol units exceeds 10, the resulting composition will have poor water resistance, and will be unsatisfactory in the use of the ink composition. In this case, an inorganic or organic pigment is usually added to the aqueous dispersion of the reactive resin. Specific examples of the pigment include white pigments such as titanium oxide, zinc white, lead white, lithobon and antimony oxide, black pigments such as aniline black, iron black and carbon black, graphite, yellow iron oxide, titanium yellow, and Hansa yellow. (10G, 5G, 3G, etc.), yellow pigments such as benzine yellow and permanent yellow, orange pigments such as chrome vermillion, permanent orange, Vulcan fast orange and indanthrene brilliant orange, iron oxide, permanent brown and para brown Brown pigment, bengalara,
Red pigments such as cadmium red, antimony red, permanent red, rhodamine lake, alizarin lake, thioindigo red, PV carmine, monolight fast red and quinacdrine red pigment, cobalt purple, manganese purple, first violet, methyl violet lake, inn Purple pigments such as Dunslen Brilliant Violet and Dioxazine Violet, and blue pigments such as ultramarine blue, navy blue, cobalt blue, alkali blue lake, peacock blue lake, Victoria blue lake, metal-free phthalocyanine blue, copper phthalocyanine blue, indathrene blue, and indigo , Chrome green, chromium oxide, emerald green, naphthol green, green gold, acid green lake, malachite green Key, other green pigments such as phthalocyanine green and poly chloro bromo copper phthalocyanine, various fluorescent pigments, metallic powder pigments, extender pigment and the like. These pigments are preferably added in an amount of 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, based on the composition excluding the photopolymerization initiator.

In addition to the plain paper containing cellulose as a main component, for example, a film or a sheet of polyethylene, polyvinyl chloride, polypropylene, polyester, polycarbonate, polyimide, etc. may be used as a target substrate when used as an ink composition. Or paper treated therewith, as well as metal, wood and synthetic wood. The composition of the present invention is suitably used particularly for paper and film.
As a method of printing the ink composition on these substrates,
A conventionally known method such as a normal printing method using offset, gravure offset, gravure, flexo, and screen methods may be used. According to the present invention, since a composition having a low viscosity can be obtained, the composition of the present invention is particularly suitable as an ink composition for gravure printing.

[0037]

The present invention will be described more specifically with reference to the following Examples and Comparative Examples. In the following, parts and% are based on weight. The viscosity was measured using an E-type viscometer. Production Example 1 (Production of carboxyl group-containing polymer) A 300-ml pressurized stirred tank reactor equipped with an electric heater was filled with diethylene glycol monoethyl ether, the temperature was raised to 250 ° C, and the pressure was adjusted by a pressure controller. Was maintained at a gauge pressure of 25 to 27 kg / cm ² . Next, while keeping the pressure of the reactor constant, 30 parts of acrylic acid as a carboxyl group-containing (meth) acrylate, 70 parts of styrene as an ethylenically unsaturated monomer, and di-t-butyl peroxide 0 as a thermal polymerization initiator. .1 part of the monomer mixture A-1 at a constant feed rate (23
(g / min, residence time: 14 minutes), continuous supply from the raw material tank to the reactor was started, and a reactant corresponding to the supply amount of the monomer mixture A-1 was continuously extracted from the outlet. Immediately after the start of the reaction, after the reaction temperature once decreased, a temperature increase due to the heat of polymerization was observed. However, the reaction temperature was maintained at 270 to 271 ° C. by controlling the heater. One hour after the start of the supply of the monomer mixture A-1 in which the temperature was stabilized, the starting point for extracting a reaction solution as a raw material for the next addition reaction was defined as a starting point. As a result of continuing the reaction for 3 hours, 4140 g of the monomer mixture A-1 was supplied, and 4130 g of a reaction product was recovered. The reaction solution was introduced into a thin film evaporator to separate volatile components such as unreacted monomers, to obtain 3800 g of a carboxyl group-containing polymer. This is called copolymer B-1. When the copolymer B-1 was analyzed by gas chromatography, no unreacted monomer was present. Further, the number average molecular weight (hereinafter abbreviated as Mn) of the copolymer B-1 in which polystyrene equivalent molecular weight determined by liquid chromatography using tetrahydrofuran as a solvent is 4100, and the weight average molecular weight (hereinafter abbreviated as Mw). Was 8300 and the polydispersity was 2.0. The acid value of the carboxyl group-containing polymer was 220.

Production Example 2 (Production of carboxyl group-containing polymer) As a monomer mixture, 25 parts of acrylic acid and 50 parts of styrene
Parts, a reaction was carried out under the same conditions as in Production Example 1 except that a monomer mixture A-2 consisting of 25 parts of α-methylstyrene and 0.1 part of di-t-butyl peroxide was used,
A copolymer B-2 which was a carboxyl group-containing polymer was obtained. When the copolymer B-2 was analyzed by gas chromatography, no unreacted monomer was present. or,
Mn of copolymer B-2 measured in the same manner as in Production Example 1
Is 3000, Mw is 6800, and the polydispersity is 2.3.
Met. The acid value of the carboxyl group-containing polymer is 19
It was 0.

Comparative Production Example 1 (Production of Carboxyl Group-Containing Polymer) A four-necked flask equipped with a reflux condenser, a thermometer, a dropping funnel, a glass tube for nitrogen replacement, and a stirrer was placed in a four-necked flask as in Example 1. 300 g of the monomer mixture A-1, 700 g of methyl ethyl ketone (hereinafter referred to as MEK) and 9 g of 2,2′-azobisisobutyronitrile were charged, and a polymerization reaction was carried out at 80 ° C. for 4 hours while blowing in nitrogen.
-1 was obtained. 350 g of the reaction product E-1 was introduced into a thin film evaporator, and volatile components such as unreacted monomers were separated to obtain 80 g of a product. This is called copolymer F-1. When the copolymer F-1 was analyzed by gas chromatography, no unreacted monomer was present. or,
Mn of copolymer F-1 measured in the same manner as in Production Example 1
Was 10500, Mw was 34300, and the polydispersity was 3.3. The acid value of the carboxyl group-containing polymer was 240.

Example 1 Copolymer B-1 was placed in a flask equipped with a stirrer and a condenser.
50 g (0.196 eq) of tripropylene glycol diacrylate [Aronix M- manufactured by Toagosei Co., Ltd.
220] 69.5 g and hydroquinone monomethyl ether 35 mg were charged and stirred at 85 ° C. to dissolve the copolymer in acrylate. Further, while maintaining the liquid temperature at 85 ° C., 0.70 g of tetrabutylammonium bromide was charged, and glycidyl methacrylate was 19.5 over 10 minutes.
g (0.137 mol, 70% mol based on the acid value) was added dropwise. Thereafter, the mixture was stirred at 95 ° C. for 4 hours to obtain 139 g of a reaction resin-containing solution C-1. The acid value of C-1 is 23.7,
The converted reactive resin excluding the reactive diluent has an acid value of 4
7.4, viscosity was 42000 cps / 25 ° C. To 45 g of the reactive resin-containing solution C-1, 2 g of Darocure 1173 (manufactured by Ciba Specialty Chemicals) as a photopolymerization initiator and 1.7 g of triethanolamine (0.011) were used.
Mol, 60% mol based on the acid value of C-1) and 53 g of water
And vigorously stirred to obtain a milky white reactive resin aqueous dispersion D.
-1 was obtained. The viscosity of D-1 was 25 cps / 25 ° C.
Various evaluations described below were performed on the obtained reactive resin aqueous dispersion. Table 2 shows the results.

Evaluation (1) Workability Evaluation The workability when the obtained reactive resin aqueous dispersion was applied to a substrate was evaluated. ○, Δ and × in the table have the following meanings. ：: No problem in work. Δ: The viscosity is somewhat high, but it can be handled. X: It is difficult to handle because of high viscosity.

(2) Heating stability test The aqueous dispersion of the reactive resin was allowed to stand at 40 ° C for 200 hours, and then visually evaluated. A: No change at all. ：: Almost no increase in viscosity. Δ: Viscosity increased. ×: Aggregates and precipitates were generated.

(3) Curability The obtained aqueous dispersion of the reactive resin was applied to Bonderite steel plate PB-144 (manufactured by Nippon Test Panel Co., Ltd.) using a bar coater # 20, and dried at 80 ° C. For 5 minutes to remove moisture from the coating. Thereafter, the coating material was repeatedly passed under an ultraviolet lamp under the following conditions to cure the coating film. UV irradiation conditions; Lamp: 80 W / cm condensing high-pressure mercury lamp Lamp height: 10 cm Conveyor speed: 10 m / min At this time, curability is determined in the following three stages depending on the number of passes until the tack disappears from the surface of the coating film. Was evaluated. The energy given to the coating film under the above irradiation conditions is about 90 mJ / cm ² per pass. ：: within 2 passes △: within 3 to 5 passes ×: the surface tack does not disappear even after passing 5 times. Also, for the cured film passed under the ultraviolet lamp 5 times under the above irradiation conditions, The following (4) and (5) were evaluated.

(4) Hardness Regarding the obtained cured film, JIS “Hand-drawing method K540”
0 ".

(5) Evaluation of coloring The coloring of the obtained cured film was visually evaluated. ：: No coloring. Δ: Slight coloring is observed. ×: Colored.

Examples 2 to 4 Glycidyl methacrylate was added to the carboxyl group-containing polymer in the same manner as in Example 1 except that the raw materials shown in Table 1 below were used. Table 1 below shows the physical properties of the obtained reactive resin.

[0047]

[Table 1]

Using the obtained reactive resin-containing solution, a reactive resin aqueous dispersion was produced in the same manner as in Example 1 except that the raw materials shown in Table 2 below were used. The obtained water dispersion was evaluated in the same manner as in Example 1. Table 2 shows the results.

[0049]

[Table 2]

Comparative Example 1 A flask equipped with a stirrer and a condenser was charged with 50 g (0.214 eq) of the copolymer F-1, 71.3 g of tripropylene glycol diacrylate, and 35 mg of hydroquinone monomethyl ether. And the copolymer was dissolved in the acrylate. Further, when the liquid temperature is 85
° C and tetrabutylammonium bromide in 0.7
1 g of glycidyl methacrylate 2 over 10 minutes
1.3 g (0.150 mol, 70% mol based on the acid value)
Was added dropwise. Thereafter, the mixture was stirred at 95 ° C. for 4 hours and 143 g
Of a reactive resin-containing solution G-1 was obtained. The acid value of G-1 is 2
5.3, the acid value of the reactive resin calculated by removing the reactive diluent from G-1 is 50.6, and the viscosity is 82,000 cps / 25 ° C.
Met. To 45 g of the reactive resin-containing solution G-1, 2 g of Darocur 1173 as a photoinitiator, 1.8 g of triethanolamine (0.012 mol, 60% mol based on the acid value of C-1) and 53 g of water were added. In addition, the mixture was stirred vigorously to obtain a milky white reactive resin aqueous dispersion H-1. The viscosity of H-1 was 38 cps / 25 ° C. The obtained water dispersion H-1 was evaluated in the same manner as in Example 1. Table 4 shows the results.

[0051]

[Table 3]

[0052]

[Table 4]

Comparative Example 2 In a flask equipped with a stirrer and a condenser, 150 g (0.214 eq) of E-1 consisting of MEK and a carboxyl group-containing polymer as the reaction product of Comparative Production Example 1, glycidyl methacrylate 21 0.3 g (0.150 mol), 0.71 g of tetrabutylammonium bromide and 35 mg of hydroquinone monomethyl ether were stirred at 90 ° C. for 6 hours to carry out an addition reaction of glycidyl methacrylate to the carboxyl group-containing polymer to obtain a reactive resin. Containing solution G-
2 was obtained. 243 of the obtained reactive resin-containing solution G-2
g (containing 100 g of MEK), 71.3 g of tripropylene glycol diacrylate, 6.3 g of Darocur 1173 as a photoinitiator, 5. triethanolamine.
8 g (0.039 mol, 60% mol based on the acid value) and 170 g of water were added and stirred, and the solvent MEK was distilled off under reduced pressure to obtain a reactive resin aqueous dispersion H-2. Aqueous dispersion H-2
Had a viscosity of 62 cps / 25 ° C. The obtained aqueous dispersion H
The evaluation of -2 was performed in the same manner as in Example 1. Table 4 shows the results.

Comparative Examples 3 to 5 An addition reaction of glycidyl methacrylate was performed on a carboxyl group-containing polymer in the same manner as in Example 1 except that the raw materials shown in Table 3 were used. Table 3 shows the physical properties of the obtained reactive resin.
Shown in Using the obtained reactive resin-containing solution, a reactive resin aqueous dispersion was produced in the same manner as in Example 1 except that the raw materials shown in Table 4 were used. The obtained water dispersion was evaluated in the same manner as in Example 1. Table 4 shows the results.

Comparative Example 3 is an example in which the reactive resin used in the present invention had an acid value exceeding the upper limit of 150, and the resulting aqueous dispersion had a high viscosity and was difficult to handle. Comparative Example 4 is an example in which a resin having a lower limit of 20 of the acid value of the reactive resin in the present invention was used, and a large amount of white aggregates precipitated in the step of forming an aqueous dispersion, and a stable aqueous dispersion was obtained. Could not get. Comparative Example 5 is an example in which a reactive diluent that does not dissolve the carboxyl group-containing polymer was used. Since the carboxyl group-containing polymer did not dissolve in the reactive diluent, the addition reaction of glycidyl methacrylate was performed. Could not do.

◎ OPV composition ○ Examples 5 to 7 Using the aqueous dispersions of the reactive resin obtained in Examples 1 to 3, the following evaluations were made as OPV compositions.
Table 5 shows the results.

Evaluation as composition for OPV (1) Curability Curability was measured under the same conditions as in the curability test except that the obtained composition was applied on coated paper using a bar coater # 20. Was evaluated. ：: within 2 passes △: within 3 to 5 passes ×: the surface tack does not disappear even after passing 5 times. Also, for the cured film passed under the ultraviolet lamp 5 times under the above irradiation conditions, The following evaluations (2) to (5) were performed.

(2) Adhesiveness A cross-cut was made on the obtained cured film with a cutter knife, a commercially available cellophane tape (manufactured by Nichiban Co., Ltd.) was pressed on the surface, and the cured film was peeled off. It was visually evaluated in the following three stages. ：: No peeling △: Part of the surface on which the tape was affixed ×: The entire surface with the tape affixed

(3) Gloss The obtained cured film was measured for gloss at 60 ° using a gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd.).

(4) Water Resistance The surface condition of the cured film, which was immersed in hot water of 80 ° C. for 1 hour and dried at 60 ° C. for 2 hours, was visually observed and evaluated according to the following three grades. ：: No abnormality Δ: Slight peeling and / or whitening occurred X: Clear peeling and / or whitening occurred

(5) Solvent resistance Using a cotton swab impregnated with acetone, a load of 500
g, the surface of the cured film obtained under the condition of one reciprocation per second was rubbed, and the number of times until the surface of the cured film caused an abnormality such as whitening or peeling was evaluated in the following three grades. ○: No abnormality in cured film after 20 reciprocations △: Abnormality in cured film after 10 reciprocations and less than 20 reciprocations ×: Abnormality in cured film after less than 10 reciprocations

[0062]

[Table 5]

Comparative Example 6 Example 4 Using the obtained aqueous dispersion of a reactive resin, evaluation as an OPV composition was performed in the same manner as in Example 5. Table 5 shows the results.

◎ Ink composition ○ Examples 8 to 10 Using the aqueous dispersion of the reactive resin obtained in Examples 1 to 3,
The compositions shown in Table 6 were dispersed in a conventional manner using a sand mill to prepare an ink composition. Using the obtained composition, the performance as an ink shown below was evaluated. Table 6 shows the results. At this time, each of the adjusted compositions had a low viscosity suitable for gravure printing.

Evaluation as ink composition (1) Curability Except that the obtained composition was applied on coated paper using a bar coater # 20, curability was the same as in the curability test described above. Was evaluated. ：: within 2 passes △: within 3 to 5 passes ×: the surface tack does not disappear even after passing 5 times. Also, for the cured film passed under the ultraviolet lamp 5 times under the above irradiation conditions, The following (2) to (6) were evaluated.

(2) Adhesion The obtained cured film was cut in a grid with a width of 1 mm using a cutter knife to form 100 square sections, and a commercially available cellophane tape (manufactured by Nichiban Co., Ltd.) was pressed on the surface. After being peeled off, it was evaluated according to the following four grades based on the number of grids remaining. ：: No peeling (residual rate 100/100) Δ: Partial peeling (residual rate 1/100 to 99/10)
0) ×: The entire surface is peeled off (residual rate 0/100)

(3) Pencil hardness The pencil hardness was measured according to JIS K5400.

(4) Water Resistance The same method as in the water resistance test for the composition for OPV was evaluated.

(5) Solvent Resistance Evaluation was made in the same manner as in the solvent resistance test for the composition for OPV.

(6) Surface Condition The surface condition of the cured film was visually observed and evaluated according to the following three grades. ：: high gloss △: slight unevenness on surface ×: severe unevenness on surface and poor gloss

[0071]

[Table 6]

Comparative Example 7 Example 4 Using the obtained reactive resin aqueous dispersion, Table 6
An ink composition was produced in the same manner as in Example 8 except that the compound shown in (1) was used. The obtained composition was evaluated in the same manner as in Example 8. Table 6 shows the results.

[0073]

According to the production method of the present invention, an aqueous dispersion of a reactive resin can be produced without any problem, and the obtained aqueous dispersion has excellent workability, stability and curability.
It is useful in various industrial fields as a paint, printing ink, adhesive, filler, molding material, resist and the like. In particular, a composition using a specific reactive diluent has excellent water resistance in addition to solvent resistance and adhesiveness.
Particularly suitable as V compositions and ink compositions.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI G03F 7/027 502 G03F 7/027 502 // C09J 4/00 C09J 4/00

Claims (6)

[Claims] (1) at least one kind of (meth) acrylate having a carboxyl group or at least one kind of another monomer having one ethylenically unsaturated group at 150 to 310 ° C. The polymer having a (meth) acryloyl group and a carboxyl group having an acid value of 50 to 500 and a number average molecular weight of 1,000 to 15,000 obtained by high-temperature continuous polymerization at a polymerization temperature of After a (meth) acrylate having an epoxy group is subjected to an addition reaction in a reactive diluent in which the coalescence is soluble to obtain a reactive resin having an acid value of 20 to 150, the reaction mixture containing the reactive resin is subjected to an alkaline aqueous medium. A method for producing an aqueous dispersion of a reactive resin, characterized in that the aqueous dispersion is dispersed in a reactive resin. 2. The polymer having a (meth) acryloyl group and a carboxyl group having an acid value of 100 to 300.
A method for producing the aqueous dispersion of a reactive resin according to the above. 3. The reactive diluent is an alkoxyalkylene glycol (meth) acrylate, an alkylene glycol mono- or di (meth) acrylate, or a polyol alkylene oxide adduct mono- or poly (meth) acrylate.
The method for producing a reactive resin aqueous dispersion according to claim 1, wherein the method is acrylate. 4. The reactive diluent is a mono- or poly (meta) of 1 to 10 mole adduct of an alkylene oxide of a polyol.
4. The method for producing a reactive resin aqueous dispersion according to claim 3, wherein the acrylate is an acrylate. 5. An active energy ray-curable overprint varnish composition comprising the aqueous dispersion of a reactive resin obtained in claim 4. 6. A composition for an active energy ray-curable ink, comprising the aqueous dispersion of a reactive resin obtained in claim 4.