WO2007026949A1

WO2007026949A1 - Emulsion type resin composition

Info

Publication number: WO2007026949A1
Application number: PCT/JP2006/317689
Authority: WO
Inventors: Tsugunori Shiraishi; Keiichi Nakamoto; Kanji Nakao
Original assignee: Nippon Shokubai Co., Ltd.
Priority date: 2005-09-02
Filing date: 2006-08-31
Publication date: 2007-03-08
Also published as: JP5554495B2; JP2009507082A

Abstract

An object of the present invention is to provide an emulsion type resin composition by the use of which film formation may be attained at a low temperature, and in addition, the coating film having excellent physical properties such as hardness, contamination resistance, water resistance, and weatherability can be formed. The emulsion type resin composition having the minimum film forming temperature of 0°C or lower, containing substantially no volatile organic compound, a Koenig hardness of a film obtained by drying the emulsion type resin composition at 23°C for 24 hours is five cycles or more, and the water absorption rate thereof is 20% by mass or less.

Description

PESCRiPTION. EMULSION TYPE RESIN COMPOSITION

TECHNICAL FIELD

The present invention relates to an emulsion type resin composition being useful in a field of coating materials for exterior and interior of buildings and plants, and more particularly to an emulsion type resin composition which can form a coating film having good film formability and excellence in properties of hardness, contamination resistance, water resistance, weather ability and the like. Furthermore, it is to be noted that a coating material containing the emulsion type resin composition, and the coating film obtained from the coating material are also included in the - present invention.

BACKGROUND ART

As a coating material for buildings and plants, changeover from organic solvent type coating materials to water-based coatings proceeds out of concern of adverse effect on environment. Among others, the emulsion type resin composition has been frequently applied. Such emulsion type resin composition forms a coating film while its resin particles fuse with each other as a result of evaporating water. In case of capable of drying by heating, fusion is easy, because the resin particles become softened and water vaporizes easily. However, for example, there is a problem in film formability of an emulsion, when the coating material is applied on an inner wall or an exterior wall of buildings and plants as it will be dried at normal temperature.

In other words, when properties of contamination resistance, abrasion resistance and the like are taken into consideration, it is desired that a comparatively hard resin is used as a coating film constituent. However, since a hard resin has a high Tg, its fusion appears hardly among resin particles at normal temperatures, whereby the film formability is inferior in this case. In order to solve the problem of poor film formability, such a manner that an organic solvent which plasticizes resin particles to promote fusion/film formation thereof is allowed to exist in the emulsion as i film forming aid has been applied. As the film forming aid, for example, texanol(2, 2, 4-trimethyM. 3-pentandiol monoisobutyrate) butylcellosoMethylene glycol monobutylether) and the like have been applied.

In recent years, however, an environmental problem gives greater importance, so that a coating material containing no volatile organic compound (VOC), i.e. a (VOC free⁾ coating material is required in even a coating material for exterior in addition to a coating material for interior of buildings and plants as a countermeasure for sick building syndrome, as a matter of course. Thus, a use of an organic solvent could not have been permitted in view of the above-described film forming aid type organic solvent.

In this connection, a number of such trials that a polymer having a high Tg is mixed with another polymer having a low Tg, whereby film formability is maintained by means of the low Tg polymer to realize a VOC free condition, while physical properties of a coating film are held in a suitable level by means of the high Tg polymer is made (For example, see Japanese Patent Application LaidOpen No. 5-112758, Published Japanese Translation 2001-514312, and Japanese Patent Application LaidOpen No. 2004-59622).

In the respective inventions described in these literary documents, however, although the purpose for VOC free is achieved, it cannot be said that improvements in film formability are sufficient, and on the contrary, even if good film formability is achieved, there is such a case wherein ' physical properties such as hardness, water resistance and the like of a film coating are insufficient.

DISCLOSURE OF THE INVENTION Problems to be solved by the Invention

Accordingly, an object of the present invention is to provide an ' emulsion type resin composition by the use of which film formation may be ' attained at a low temperature, and in addition, a coating film having < excellent physical properties such as hardness, contamination resistance,- water resistance, and weatherability can be formed.

Means for solving the Problems

The present invention is concerned with an emulsion type resin composition having the minimum film forming temperature ^"of O⁰C or lower and containing essentially no volatile organic compound, and a Koenig hardness of a film obtained by drying the emulsion type resin« composition at 23⁰C for 24 hours is five cycles or more, and the water absorption rate ^■ thereof is less than 20% by mass.

Effects of the Invention

According to the present invention, there is provided the emulsion type resin composition applied for a coating material having'the minimum film forming temperature (MFT) of O⁰C or lower without incorporating a volatile organic compound (VOC) thereinto. In accordance with the emulsion type resin composition, since the resulting coating film has a good hardness and a water absorption rate, it is suitable for applying, for example to an exterior or an interior coating material for buildings and plants. Particularly, in case of an emulsion type resin composition containing a waterdispersible pofyrner (A) having 50 to 15O⁰C glass transition temperature and 5,000 to 50,000 weight average molecular weight, the MFT can be suppressed to a low value, even in case of a VOC free condition, and ir addition, the resulting coating film has an excellent hardness and water absorption rate, so that the above -de scribed emulsion type resin compositior relates to a preferred manner of practice of the present invention.

PREFERRED MODE FOR CARRYING OUT THE INVENTION

As described above, a number of such trials that a polymer having a high Tg is mixed with another polymer having a low Tg, whereby film formability is maintained to realize a VOC free condition, while physical properties of a coating film are held in a suitable level. In these prior arts, however, there is no study about molecular weights of the respective polymers. In this respect, the present inventors have studied an emulsion type resin composition from which a film coating having more excellent physical properties can be obtained, and further a VOC free condition can b( achieved. As a result, it has been found to be effective that a molecular weight of the high Tg polymer is suppressed to a low value_* ¹ and thus, the above "described present invention is achieved. In the following, the presen invention will be described in detail wherein the term "polymer" in the invention includes copolymers, and ternary or higher copolymers in additior to homopolymers. Furthermore, the term "monomer" in the present invention means all the addition polymerization type monomers. -

First, the emulsion type resin composition of the invention is in a VOC free condition. This is because the major premise of the present invention resides in this point wherein the term "VOC" means a volatile organic compound the boiling point of which is within a range of from i 50"100⁰C to 240"260°C among the organic compounds having 'such a possibility that the organic compound in question might be a source of contamination of the air in a room which is classified by WHO. The emulsion type resin composition of the present invention may contain the - volatile organic compound of 1% by mass or less (more preferably, 0.5% by mass or less, most preferably, 0% by mass). In the present invention, the VOC does not include a neutralizing agent which will be described hereinbelow. Because the present invention attains a VOC free condition b> incorporating no organic solvent used in a film forming aid into the emulsior type resin composition. * ^! "

Moreover, the emulsion type resin composition of the present invention has the minimum film forming temperature (MFT) of O⁰C or lower Such a practical level wherein a coating material is prepared from the emulsion type resin composition, and then, the resulting coating material is applied to the exterior wall and the like of buildings and plants in the outsidi air is taken into consideration, so that the MFT is made to be O⁰C or lower. The MFT is measured pursuant to JIS K6828-2 (2003); and it corresponds tc a boundary temperature between a region wherein a film is form'ed.and another region wherein no film is formed in the case when the emulsion is applied to a flat plate having an appropriate temperature gradient in a strip-shaped pattern. Thus, the MFT is defined by the expression "the minimum temperature at which a uniform film accompanied with no crack is obtained". In the present invention, a film having 250 μm thickness (wet) is prepared with an applicator on a stainless steel flat plate with no groove, the minimum film forming temperature (⁰C) is measured within a measuring temperature range of from -5⁰C to +3O⁰C by using a MFT tester ("TP-801 LT type" tester manufactured by Tester- Industry Co., Ltd.). The presence of cracks is judged by visual observation in accordance with the , , above-described JIS K6828-2.

The film obtained by drying the emulsion type resin composition of the present invention at 23⁰C for 24 hours exhibits a value of 5 or more cycles of Koenig hardness. The Koenig hardness is preferably 7 or more cycles, and more preferable is 10 or more cycles. In this case, the term "film" means the film formed only from the emulsion type resin composition ' of the present invention, but not the "coating film" obtained from a coating material which is prepared by incorporating a coating additive or the like into the emulsion type resin composition of , the invention. In the following description, it is defined for convenience that the "film" means the one obtained only from the emulsion type resin composition of the present • ' invention, while the film obtained from the coating material of the present ^■ invention is called by the name of "coating film". In the case where the above-described film exhibits a Koenig hardness of 5 or less cycles, a coating film having an excellent hardness to be an object of the present. invention cannot be obtained.

The Koenig hardness corresponds to a value measured by the use of _.ε pendulum hardness meter (Koenig type; Model 299 manufactured by Ericksen Company (Germany)). More specifically, a film having 250 μm . , thickness of the emulsion type resin composition (wet; 40 to 60% solid- ^{j "} content concentration) is applied onto a glass plate by means of an- applicato: the film is allowed to stand at 23⁰C for 24 hours, and then, the plate coated with the film is set in the above-described pendulum hardness meter wherein a measurement initial angle is to be 6°, and a reciprocating number of times of the pendulum (a tungsten carbide steel ball) until a measureineni finished angle thereof comes to be lower than 3° is determined as Koenig hardness (cycles). In the case when tack appear on the film; 'the pendulum stops. Accordingly, the larger number of cycles means the harder film, so that the performance of the film is good. ^' ■ ' ' ■ ^{■ ■ >} ■ < ^•

The film obtained by drying the emulsion type resin composition. at • 23⁰C for 24 hours exhibits a water absorption rate of less than 20% by mass. When the water absorption rate is 20% by mass or more, the water ' ^{■ •} resistance of the film becomes low. As a result, when the coating material is applied, for example, to the exterior of a building, there are' possibilities that the coating film is peeled off from the exterior wall or blisters appear on the coating film, due to rainfall and the like, so that it is not desirable. The water absorption rate is preferably 15% by mass or less, more preferaby 10°/ by mass or less. In the present invention, a value measured by the following manner is determined to be a water absorption rate. - ' '

Namely, the emulsion type resin composition is applied to a releasing paper so as to obtain a film having 250 μm dry film thickness, and the emulsion type resin composition is dried at 23⁰C for 24 hours. ^! The resulting film is cut out into a proper size (around 5 cm x 5 cm⁾, the film cut out after i is precisely weighed is immersed into tap water at 23⁰C for 24 hours, it is then taken out and water drops are removed, and it is precisely weighed. ' The water absorption rate (% by mass) is determined in accordance with a formula 100 x (the mass of a sample after immersion - the mass of the ' ' ' sample before immersion⁾/the mass of the sample before immersion wherein an average value in case of n = 3 is determined.

In order to obtain the film having the Koenig hardness arid the wate] absorption rate which are within the above -described preferred range by ^{! i} using an emulsion type resin composition' being in VOC free, having 0°C or lower MFT, it is desired that the emulsion type resin composition of the ' ' present invention contains the water-dispersible polymer (A) having 50 to ' 15O⁰C Tg and 5,000 to 50,000 weight average molecular weight (Mw). ^" ' When a water-dispersible polymer (A) having a high Tg and a<comparativel;y lower molecular weight is used as the water-dispersible polymer (A), a' hardness of the film is maintained without damaging the film formability. ' In the case when a Tg of the water-dispersible polymer (A) is lower than " 50°C_; it is difficult to obtain 5 cycles or more Koenig hardness, while the Tg exceeds 15O⁰C, it becomes difficult to obtain MFT of not more than O⁰C. More preferably, the lower limit of Tg is 55⁰C, while the upper limit is 145⁰C On one hand, when an Mw is less than 5,000, such excessively low molecula] weight brings about such a case wherein Koenig hardness and water absorption rate cannot be maintained in the preferred range, while when the Mw exceeds 50,000, there is such a fear that the MFT cannot be maintained at a temperature of O⁰C or lower. More preferably, the lower limit of the Mw is 5,500, while the upper limit is 20,000, and the further preferable upper limit is 10,000.

Since the above-described water- dispersible polymer (A) is "water dispersible", it should not be a polymer which dissolves into water. Howeve it is preferred that the polymer is copolymerized with a water-soluble monomer so as to dissolve partially into water. Particularly, it is preferred that when the polymer has an acid value of 20 to 70 mgKOH/g, the film formability becomes more excellent. In this connection, it may be considered that the polymer having the acid value within the above -de scribed range is dissolved partially into water (it is not dissolved completely into water), so that plasticizing effect of the polymer appearsidue to water, whereby emulsion particles fuse easily with each other to enhance film formability. For expecting such improvement in film formability, it is desired that an acid value of the waterdispersible polymer (A) is maintainec to be 20 mgKOH/g or more. It is more preferred that the lower limit of the acid value is 25 mgKOH/g, and further preferable is 35 mgKOH/g. Howeve- when the acid value exceeds 70 mgKOH/g, the resulting polymer becomes a water-soluble polymer, or the above-described water absorption rate of the film becomes excessively high, thus, it is not desirable. The acid value ma\ be obtained by calculating from an application amount of an acid>' ^! group-containing monomer, and further, the acid value of the resulting waterdispersible polymer (A) may be determined by titration with the use o KOH. In case of determining acid value by titration, the waterdispersible polymer (A) may be dissolved into a mixed solvent of tetrahydrofuran, methanol, and water, then, a carboxylate neutralized is allowed to return to an acid by means of hydrochloric acid, thereafter neutralization titration is conducted with use of KOH.

Moreover, the expression "the water-dispersible polymer (A) is not dissolved into water" does not direct to such a condition that a neutralized polymer product exhibits a transparent and colorless solution,_' but it directs to a state wherein light is diffused by the particles, whereby the* solution becomes clouded.

' It is preferred that the emulsion type resin composition of the presen invention contains a water-dispersible polymer (B) in addition^ιto the > • < above-described water-dispersible polymer (A) for the sake' of changing < variously physical properties of the resulting coating material'. -In this case when the water-dispersible polymer (B) has a Tg of O⁰C or lower (more preferably, -1O⁰C or lower), the film formability is remarkably improved, 'so that the physical properties such as elasticity of the coatirig film become alsc good, and accordingly, this emulsion type resin composition is a preferred ^l < manner of practice. However, when a Tg of the water-dispersible polymer (B) is too low, there is a case where the coating film exhibits surface tack, *anc thus, it is preferred that the lower limit of Tg is -4O⁰C (more preferably, -35⁰C).

In the case where the waterdispersible polymer (A) is used together with the waterdispersible polymer (B) in the emulsion type resin composition of the present invention, it is preferred that the waterdispersible polymer (A) is 10 to 50% by mass, and the waterdispersible polymer (B) is 90 to 50% by mass, when the total of the waterdispersible polymer (A) and the waterdispersible polymer (B) is 100% by mass. More preferred is that the water-dispersible polymer (A) is 20 to 40% by mass, and the water-dispersible polymer (B) is 80 to 60% by mass. There is such a tendency that when an amount of the water-dispersible polymer (A) is too much, the film formability decreases, while when a conten of the water-dispersible polymer (B) is too much, the film hardness decreases.

Moreover, the emulsion type resin composition of the present invention may contain further a water-dispersible polymer (C) having a > weight average molecular weight of more than 50,000 in addition to the above-described water-dispersible polymer (B). Due to the addition of the water-dispersible polymer (C), the coating film hardness is improved. In this connection, it is preferred that the waterdispersible polymer (C) has a Tg of O⁰C or higher. More preferable is a Tg of 3O⁰C or higher, and a still further preferable Tg is 5O⁰C or higher.

In the above-described case, it is preferred that the water-dispersible polymer (A) is 10 to 50% by mass, the water-dispersible polymer (B) is 85 to 20% by mass, and the water-dispersible polymer (C) is 5 to 30% by mass, ' when the total of the waterdispersible polymers (A⁾, (B), and (C) is 100% by mass. There is such a tendency that when the content of the waterdispersible polymer (A⁾ or (C) is too much, the film formability decreases, while when the content of the waterdispersible polymer (B) is toi much, the film hardness decreases.

The radically polymerizable monomers which may be used for the , , synthesis of the waterdispersible polymers (A) to (C) are not specifically restricted, but for the sake of adjusting the acid value of the i ■ waterdispersible polymer (A) within a the above-described preferred range, carboxyl group -containing monomers are used. A specific example of the carboxy group -containing monomers includes (meth)acrylic acid, maleic acid fumaric acid, crotonic acid, itaconic acid, citraconic acid, maleic anhydride, monomethyl maleate, monobutyl maleate, rnonomethyl itaconate, monobuty itaconate, vinylbenzoic acid, monohydroxyethyl oxalate (meth)acrylate, carboxyl group terminated caprolactone-modified acrylate (for _'example,. "PLACCEL® FA" series, manufactured by Daicel Industries, Ltd.), carboxyl ■ group terminated caprolactone modified methacrylate (for example, "PLACCEL® FMA" series, manufactured by Daicel Industries, Ltdi), and tht like. And above these can be used in combinations of two or more of them. Among others, (meth)acrylic acid is preferred. Of course, these carboxyl group -containing monomers may be used for synthesizing the .waterdispersible polymers (B) and (C).

The following radically polymerizable monomers are preferred as the other applicable monomers. The specific examples thereof include :

Alkyl or cycloalkyl ester monomers of (meth) acrylic acid such as^ ^■ methyl (meth)acrylate, ethyl (meth) aery late, propyl (meth)acrylate, isopropyl acrylate, n-butyl (meth) aery late, isobutyl (rneth)acrylate, n-butyl (meth)acrylate, t "butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, iroctyl (meth) acrylate, lauryl (meth)acrylate, dodecyl (meth)aciylate,' stearyl i (meth)acrylate, 2-ethylhexylcarbitol (meth) acrylate, isobdrnyl ■ (meth) acrylate, cyclohexyl (meth) acrylate, methylcyclohexyl (meth⁾ acrylate, tert-butylcyclohexyl (meth) acrylate, and cyclododecyl (meth) aory late.

Hydroxyl group -containing monomers such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxyprdpyl • (meth) acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl '

(meth) acrylate, and caprolactone-modified hydroxy (meth) acrylate (for- , example, "PLACCEL® F" series, manufactured by Daicel Chemical - Industries, Co., Ltd.).

Alkoxyalkylesters of (meth)acrylic acid such as methoxybutyl ^> ' (meth) acrylate, methoxyethyl (meth) acrylate, ethoxybutyl (meth) acrylate, ■ and trimethylolpropanetripropoxy (meth)acrylate.

Hydroxysilane and/or hydrolyzable silane group -containing vinyl ' ' monomers such as vinyltrimethoxy silane, vinyltriethoxy silane, vinyltridnethoxyethoxjOsilane, γ-(meth)acryloyloxypropyltrimethoxysilane, 2 ^■ styrylethyltrimethoxy silane , vinyltrichlorosilane , y (meth) acryloy loxy propylhydroxysilane, and y (meth) acryloy loxypropyl methylhydroxy silane. <

_'Nitrogen-containing monomers such as (meth)acrylamide, N-monomethyl (meth)acrylamide, N-monoethyl (meth)aciylamide, ' N,N"dimethyl (meth)acrylamide, N-n-propyl(meth)aciylamide, N-isopropyl (meth) aery lamide, methylenebis (meth)acrylamide, N-methylόl ^■'' (meth)acrylaniide, N-buthoxymethyl (meth)acrylanπde, (meth)acryloyloxyethyltrimethyl ammonium chloride, dimethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylamide, ethylene oxide addition (meth)acrylate of morpholine, N-vinylpyridine, N-vinylimidazole, N-vinjdpyrrole, N-vinylpyrrolidone, N-vinyloxazolidone, N-vinyl succinimidc N-vinylmethylcarbamate, N,N-methylvinylacetamide, 2-isopropenyl-2-oxazoline, 2-vinyl-2-oxazoline, and (meth)acrylonitrile.

Aziridinyl group -containing monomers such as (meth)acryloylaziridine, and 2-aziridinylethyl (meth)acrylate.

Epoxy group -containing monomers such as glycidyl (meth)acrylate, α-methyl glycidyl acrylate, crmethyl glycidyl methacrylate (e.g. "MGMA" manufactured by Daicel Chemical Industries Company), allyl glycidyl ether, oxocyclohexyl methyl (meth) acrylate, 3,4-epoxycyclohexyl methyl acrylate (e.g. "Cyclomer ® A400" manufactured by Daicel Chemical Industries Company), 3,4-epoxycyclohexyl methyl methacrylate (e.g. "Cyclomer® MlOO' manufactured by Daicel Chemical Industries Company). > ^■ •

Aromatic vinyl monomers such as styrene, crmethylstyrene, vinyl toluene, and chloromethylstyrene. • >

Garbonyl group -containing monomers such as acrolein, diacetone acrylamide, formyl styrol, vinylalkyl ketone having 4 to 7 carbon atoms (vinylethyl ketone and the like), (meth) aery loxy alkyl propenal, acetonyl acrylate, diacetone (meth) acrylate, 2-hydroxypropyl acrylate acetylacetate, and butane diol" 1,4" acrylate acetylacetate.

Perfluoroalkyl (meth) acrylate s such as»perfluorobutylethyl (meth)acrylate, perfluoroisononylethyl (meth)acrylate, and ^> perfluorooctylethyl (meth) aery late.

. Ultraviolet stability monomers such as

4-(meth)acryloyloxy2₎2,6,6-tetramethylpiperidine (e.g. "ADK STAB ® LA- 87", manufactured by ADEKA Corporation), 4-(meth)acryloylamino-2,2,6,6-tetramethylpiperidine, 4"(meth)acryloyloxyl,2,2,6_!6-pentamethylpiperidine (e.g. "ADK STAB ® ^• LA-82", manufactured by ADEICA Corporation), 4-(meth)acryloyl"l-methoxy2,2,6,6-tetramethylpiperidine, 4-cyano-4-(meth)acryloyloxy2,2,6,6-tetramethylpiperidine, ' l^met^acryloyl^^met^acryloylamino^^jβjβ-tetramethylpiperidine, ' 4-crotonoylamino-2,2,6,6-tetramethyrpiperidine, • 4-(meth)acryloylamino-l,2,2,6,6-pentamethylpiperidine, ' ^{r ■} '4-cyano-4-(ineth)acryloylamino-2, 2,6, 6-tetramethylpiperidine,' ^■ 4-crotonoyloxy 2,2,6.6-tetramethylpiperidine, ' ' : .. • l-(meth)acryloyl-4-cyano-4"(meth)acryloylamino"2,2,6,6 ^■■ '' ' . ^■tetramethylpiperidine, and -crotonyl-4-crotonyloxy^;2,2,6,6 ^■tetramethylpiperidine.

■ Benzotriazole ultraviolet absorption monomers such as ^• ' 2-[2^t-hydroxy5'-(meth)acryloyloxymethylphenyl]-2H-benzotriazole,^{> i} . '

2-[2"hydroxy5"(meth)acryloyloxyethylphenyl]-2H"l_;2,3-benzotπazole, 2"[2'-hydiOxy5'-(meth)acryloyloxymethylphenyl]-5-t-butyI-2H-benzotriazole, 2-[2^l-hydroxy5'-(meth)acryloylaminomethylio'"tert-octylphenyl]-2H ' ^•

"benzotriazole,

2"[2'-hydroxy 5'-(meth)acryloyloxypropylphenyl]-2H"benzotriazolθ ' ■ 2-[2'-hydroxy5'-(meth)acryloyloxyhexylphenyl]-2H-benzot'riazole,' > 2-[2'-hydroxy3'-t-butyl-5'-(meth)acryloyloxyethylphenyl]-2H-benzotriazole,

2"[2'-hydroxy3¹-t-butyl-δ^!-(meth)acryloyloxyethylphenyl]-5-chloro"2H

^■benzotriazole,

2-[2'-hydroxy5'-t-butyl-3'"(meth)acryloyloxyethylphenyl]-2H-benzotriazole,

2"[2'-hydroxy5'-(ineth)acryloyloxyethylphenyl]"5-chloro-2H-benzotriazole,

2-[2'-hydroxy5'(meth)acryloyloxyethylphen3d]-5-cyano-2H"benzotriazole,

2-[2'-hydroxy5'-(ineth)acryloyloxyethylphenyl]-5-t-butyl-2H-benzotriazole, and 2-[2'"hydroxy5'-(β-(m.eth)acryloyloxyethoxy)-3'"t-butylphenyl]

-4-t-butyl"2H-benzotriazole.

Benzophenone ultraviolet absorption monomers such as 2-hydroxy4-(meth)acryloyloxybenzophenone, <

2-hydroxy4-[2"hydroxy3"(meth)acryloyloxy]propoxybenzophenone, 2-hydroxy4-[2"(meth)acryloyloxy]ethoxybenzophenone, 2-hydroxy4"[3-(meth)acryloyloxy2-hydroxypropoxy]benzophenone_; and 2-hydroxy3-tert-butyl-4-[2-(meth)acryloyloxy]butoxybenzophenone.

One, two or more of the above -de scribed compounds or monomers may be used.

Adjustment of the Tg of the waterdispersible polymers (A), (B), and (C) may be made from the Tg (K) of a homopolymer and the mass fraction of a monomer by using the following calculating formula. It is desired to decide a monomer composition based on the Tg calculated as the standard. [Formula l]

1 W_x W₇ W_n

Tg Tg_: Tg₂ Tg_n wherein Tg represents the glass transition temperature (K) of a polymer to be determined, Wi, W2, ... W_n represent mass fractions of the respective monomers, and Tgi, Tg2, ... Tg_n represent glass transition temperatures (K) of the homopolymers of the corresponding monomers. Tg of homopolymers may be obtained from the values described in publications such as "POLYMER HANDBOOK" (the 4th edition: published from John Wiley & Sons, Inc.⁾. Furthermore, Tg of polymers may be measured by means of DSC (differential scanning calorimetry equipment), DTA (differential thermal analyzer), or TMA (thermomechanometry equipment).

The emulsion type resin composition of the present invention is preferably produced in accordance with emulsion polymerization in the presence or absence of an emulsifier. However, such a manner that the polymer obtained by bulk polymerization, or solution polymerization, other than suspension polymerization is emulsified in accordance -with after-emulsification is also applicable. In the case of using the water dispersible polymer (A), the water- dispersible polymer (B), and furthei as needed, the waterdispersible polymer (C) together, they may be blended with each other after they are separately polymerized. Otherwise, an emulsion composed of the polymers (A), (B), and (C) may be synthesized in accordance with a multistage emulsion polymerization.

In case of synthesizing the polymer (A) and (B) in accordance with the multistage emulsion polymerization, any of such methods that for example, a raw material monomer of the polymer (A) is previously polymerized, and then, a raw material monomer of the polymer (B) is polymerized thereafter, and vice versa; and that raw material monomers of the respective polymers are polymerized separately in a certain number. of stages is applicable. In this respect, when such a method that the raw ' ^■ material monomer of the polymer (A) is polymerized prior to the final stage, and particularly, that the polymer (A) is previously obtained by ' • polymerization, and then, the polymer (B) is obtained thereafter by ^• polymerization is adopted, an emulsion having excellent film formability is obtained, besides, extension physical properties of the coating film become improved, so that the latter method is desirable. In case of containing also the watei-dispersible polymer (C), it is preferred to conduct polymerization ' of the polymer (C) prior to that of the polymer (A). A manner for'adding raw material monomers may be any of one shot addition, monomer dropping,' ' pre-emulsion dropping and the Like methods. '

In the emulsion polymerization, well-known materials may be used not restrictively as a radical polymerization initiator. A specific example of them includes persulfates/peroxides such as ammonium persulfate, 'sodium persulfate, hydrogen peroxide, t-butyl hydroperoxide, and t-butyl ' peroxybenzoatei and water-soluble azo-based compounds such as ^• ' > '" 2,2'-azobisisobutylonitrile, 2,2'-azobis(2-amidinopropane)hydiOch'loride, ' ⁽ " 2,2'-azobis(2,4-dimethylvaleronitrile), and 4,4'-azobis(4-cyanopentanoic acid} An application amount of a radical polymerization initiator is preferably ^' ' around 0.1 to 1% by mass with respect to 100% by mass of raw material ^: . monomers. Moreover, a reducing agent such as sodium bisulfite, ferrous' ' chloride, ascorbates, and Rongalite may be incorporated into the ' '•< '-' above-described initiator in order to accelerate the rate of polymerization, or in case of the polymerization at a low temperature. " ^{• ■} '- ' . ' ¹J > ^■

Furthermore, an emulsifier to be applied is not particularly' ' '^u ' • " " restricted, but any of the following emulsifiers may be added. An example thereof includes anionic surfactants such as fatty acid salts, e.g.' sodium laurylsulfate, higher alcohol sulfate, alkyl benzene sulfonates such as sodium dodecylbenzene sulfonate, polyoxyethylene alkyl ether sulfates, alky aiyl polyether sulfates such as ammonium polyoxynonylphenyl ether sulfonate, polyoxyethylene polyoxypropylene glycol ether sulfates, reactive emulsifiers such as monomers having sulfonic acid group or sulfuric ester group, and emulsifiers containing (meth)acryloyl group; nonionic surfactants such as polyoxyethylene alkylphenyls, e.g. polyoxyethylene' alkyl ethers, anc polyoxynonylphenyl ether, sorbitan fatty esters, polyoxyethylene fatty esters polyoxyethylene-polyoxypropylene block copolymers,¹ and reactive nonionic surfactants; cationic surfactants such as alkylamine salts, and quaternary ammonium salts; and well-known emulsifiers (dispersants) such as (modified) polyvinyl alcohol. ' ^■ ■^{' •}' "

The above-described emulsifiers may be used alone or in ^! combinations of two or more of them wherein an application' amount'of an emulsifier may be around 0.01 to 10% by mass with respect to 100% by mass of.raw material monomers. In order to regulate an Mw of the ^•'■^' < waterdispersible polymer (A), a chain transfer agent such as 2-ethylhexyl thioglycolate, t-dodecyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, mercaptoacetic acid, mercaptopropionic acid, 2-mercaptoethanol',¹ α-methylstyrene, and α-methylstyrene dimer may be used' wherein an application amount of the chain transfer agent may be 0.5 to 10% by mass' '

, with respect to 100% by mass of raw material monomers. An excess ' ^• amount of the chain transfer agent bi'ings about a fear of decreasing a molecular amount of the waterdispersible polymer (A).

Although it is not particularly restricted, a polymerization temperature is to be 0 to 100⁰C, and preferably 50 to 9O⁰C, while a polymerization period of time is to be 1 hour to 15 hours.

It is preferred that the emulsion type resin composition of the presen invention is neutralized by a neutralizing agent for enhancing the _'stability thereof. The neutralizing agent is not particularly restricted, but any of well-known neutralizing agents which are used in case of neutralizing an ' acid group. A specific example includes alkali metal compounds such as sodium hydroxide, and potassium hydroxide! alkaline earth metal ' compounds such as calcium hydroxide and calcium carbonate; ammonia; anc water-soluble organic amines such as dimethylaminoethanol, monomethylamine, dimethylamine, trimethylamine, monoethylanϋne, diethylamine, triethylamine, monopropylamine, dimethylpropylamine, monoethanolamine, diethanolamine, triethanolamine, ethylenediamine, ' diethylenetriamine, and 2-amino-2-methyM-propanol. Among¹ others-, >' s ¹ ammonia, dimethylaminoethanol, trimethylamine and the like are preferred¹

In the case when a neutralizing agent is added to the emulsion type resin composition, it is preferred to add 0.5 to 1.5 equivalent amount of the neutralizing agent with respect to one equivalent amount of a carboxyl group amount contained in the water-dispersible polymers (A) and (B), and the - ' > more preferable lower limit of the neutralizing agent amount is 0.6 '> ^■ equivalent amount; still further preferably 0.7 equivalent amount.¹ ' The " > more, preferable upper limit of the neutralizing agent amount is 1.2 ' - < ' < ' ■equivalent amount, and still further preferably 1.0 equivalent amount: '¹In¹ case of applying the water-dispersible polymer (C), an application amount of the neutralizing agent is to be within the above -de scribed range with respec to 1 equivalent amount of the total amount of the carboxyl groups contained in the water-dispersible polymers (A), (B), and (C).

A time for adding the neutralizing agent is not particularly limited. For instance, in the case where the multistage emulsion polymerization is applied wherein the raw material monomer of the water-dispersible polymei (A) are polymerized in the first stage, and the raw material monomer of the water-dispersible polymer (B) is polymerized in the second stage,- the neutralizing agent may be added as a shot after completing the polymerization in the second stage. On one hand, it may be ai'ranged in such that 0 to 50% by mass (more preferably 10 to 30% by mass) in 100% by mass of the neutralizing agent is added as a shot to the reaction' vessel after the polymerization in the first stage, and 50 to 100% by mass (more preferably 70 to 90% by mass) of the neutralizing agent is dropped into the ' reaction vessel during the polymerization of the raw material monome in 'the second stage. The latter addition manner is preferably applied, so that the temporal stability of the resulting emulsion type resin composition becomes more excellent, and in addition, an emulsion film hardness and a coating film hardness are also remarkably improved.

In the emulsion type resin composition of the present invention, the most preferable manner is either the one wherein the resin component is ■ composed of the water-dispersible polymer (A) and the water-dispersible polymer (B), or the one wherein the water-dispersible polymer (C) is further included in addition to the above-described waterdispersibleφolymers (A) and (B). The emulsion type resin composition is suitably used as the major component of an exterior and interior coating material for buildings and plants. In case of being served for a coating material, it is preferred to add i crosslinking agent for improving physical properties of the coating film by crosslinking the coating film. A preferred example of the crosslinking agents includes water-dispersible isoσyanates, and hydrazine compounds.

The water-dispersible polyisocyanates mean the ones wherein a part of the isocyanate groups of aliphatic or alicyclic polyisocyanates (including also the derivatives thereof) such as hexamethylene diisocyanate, isophorone diisbcyanate is combined with an ethylene oxide chain to be ■ . water-dispersible.' For instance, they are available on the market in the' names of "Aquanate © 100", "Aquanate® 110", "Aquanate® 200", . "Aquanate® 210" and the like manufactured by Nippon Polyurethahe ^■Industry Co., Ltd.; "Bayhydur® TPLS-2032", "SUB-Isocyanate-L801" and the like, manufactured by Sumika Bayer Urethane Company! "Takenate ® WD-720", "Takenate® WD-725", "Stafyloyd (phonetic). WD:220". and the like, manufactured by Mitsui Takeda Chemicals, Inc.! "Lezamin ®< D"56". and the like, manufactured by Dainichiseika Industries, Inc.! and accordingly, any oi ^■the materials may be used. ^{! ι} .^{■ ■} ■

In case of applying a water-dispersible polyisocyanate, it is^preferred to introduce a hydroxyl group as a crosslinkage point into any one or more oi polymers used for the emulsion type resin composition of the present invention in the water-dispersible polymers (A), (B), and (C). M In this respect however, isocyanate group reacts also with carboxyl group, no hydroxyl > > ■ group may be permitted. In the water-dispersible polyisocyanate, iti is preferred to use an isocyanate group in such that the isocyanate group 'comes' to be 0.5 to 2.5 equivalent amount, when the total of the carboxyl group and the hydroxyl group is 1 equivalent amount.

As a hydrazine compound, dicarboxylic acid hydrazide having 2 to 1C carbon atoms, and preferably 4 to 6 carbon atoms is suitable. A crosslink^ reaction is carried out between the hydrazine compound and the carbonyl ' group derived from the above-described carbonyl group -containing monomers. Accordingly, when the hydrazine compound is used as a crosslinking agent, a unit derived from the carbonyl group -containing '^• monomers has been introduced into any one or more polymers used for the emulsion type resin composition of the present invention in the i ' ^• waterdispersible polymers (A), (B), and (C). An application amount of the hydrazine compound is preferably 0.1 to 5 equivalent amount with respect tc 1 equivalent amount of carbonyl group.

A specific example of the dihydrazide dicarbonate includes dihydrazide oxalate, dihydrazide malonate, dihydrazide succinate, ' ¹ -¹ dihydrazide gultarate, dihydrazide adipate, dihydrazide sebacate, dihydrazide maleate, dihydrazide fumarate, and dihydrazide itaconate. _^Furthermore, aliphatic water-soluble hydrazines having 2 to '4 carbon atom^'s such as ethylene-l,2"dihydrazine, propylene- 1,3-dihydrazine_/and butylene-l,4-dihydrazine are also applicable. i ' To a coating material containing the emulsion type resin compositior of the present invention, raw materials used commonly for blending of' a coating material and a variety of additives may be applied according to needs Examples of these additives include pigments, inorganic- or organic-based fillers, thickeners, lubricants, hydrophilicity modifying agents, watei-soluble or waterdispersible resin, dispersants (the above-mentioned emulsifiers), waterproofing agents, crosslinking agents, film formation aids, thermofusible materials, pH adjusters, and viscosity adjusters. As the pigments, those for a coating material, i.e. inorganic pigments such as titanium dioxide, lithopone, iron oxide, and chromium oxide as well as well-known organic pigments are used. As the fillers, calcium carbonate, ■ baryte, mica, silica sand and the like are applied. As the thickeners! well-known compounds having thixotropy providing effect such as oxidized polyethylene-based, amide-based, crosslinked polyacrylate-based, and silica-based materials may be used.

In the case where a pigment and a filler are added in the form of a coating material, it is adjusted in such that a volume concentration PVC of ^■ the pigment and the filler in a solid content of the coating material does-not exceed 40% by volume, whereby a good coating film performance is obtained and it is desirable. A viscosity of the coating material may be^r optionally changed in accordance with a manner for coating, but usually adjusted to be 5 to 40 Pa - s (23⁰C).

An object to which the coating material of the present invention is applied (a material to be coated) is not particularly limited, but it is recommended to apply on an exterior wall constituting material in view of directing improvements in performance of a coating material used for the exterior of buildings and plants. Specific examples of them include inorganic materials such as mortar, concrete, ALC (autoclaved light-weight concrete), PC (prestressed concrete) plates, cement slates, and various (metal"based, gypsum-based or the like) siding boards! and organic materials such as woods, and a variety of plastics (including FRP). Since the coating material of the present invention is excellent in adherability, it is also^' ' , possible to apply directly to a coating film formed on the above-described materials. Examples of existing finishing coating materials for constituting such coating film include a variety of organic-based coating materials such as single layer elastic coating materials, synthetic resin emulsion paints, urethane resin coating materials, acrylic resin-based enamel paints, vinyl^* chloride resin-based coating materials, sprayed tile, resin lysπrbased coating materials and the other well-known materials; and inorganic-based coating materials such as cement lysine-based, cement stucco-based, and' siliceous-based materials.

The coating manner may be a well-known manner such as a roller • ' method, air spray method, and airless spray method. An application- quantity of the coating material may be suitably changed in response to a" solid content concentration or a specific gravity of the coating material', a type or a use application of a material to be coated, and the'presence of a •' pattern.

Examples

In the following, the present invention will be described in detail by referring to examples, but it is to be noted that the scope of the present ^ invention is not restricted by only these examples. In these examples, "%" means "% by mass" and "part'' means "part by-mass", so far as it is_'not_" - specifically mentioned. Synthesis Example 1

First, the water-dispersible polymer (A) was synthesized in emulsion polymerization of the first stage. A flask equipped with a dropping funnel, ε stirrer, a nitrogen introducing tube, a thermometer, and a reflux condenser was charged with 273.3 parts of deionized water. A pre-emulsion was prepared by blending sufficiently all of, 7.5 parts of 20% aqueous solution of "Haitenol ® 18E" (an anionic surfactant manufactui'ed by Daiichi Kogyo > Company; being polyoxyethylene alkylphenylether ammonium sulfate), 10.6 parts of deionized water, and the first stage monomers indicated as the identification number 1-1 in Table 1 with each other. The dropping funnel was charged with the resulting pre-emulsion. Then, 42.3 parts of the pre-emulsion in the whole of them were added to the flask as a shot, and the temperature was elevated to 75⁰C with stirring while blowing moderately nitrogen gas thereinto.

To the resulting mixture, 30.0 parts of 5% aqueous potassium persulfate were added to start the polymerization. In this case, the inside temperature of the flask was elevated up to 8O⁰C and maintained for 10 minutes; the reaction so far being called initial reaction. After completing the initial reaction, the remaining part of the above-described pre-emulsion for the first stage was dropped uniformly for 15 minutes while maintaining the inside temperature to 8O⁰C. After completing the dropping, the dropping funnel was washed with 10 parts of deionized water, and the washed water was added to the flask. Thereafter, the contents of the flask were maintained at the same temperature for 30 minutes, "and the polymerization in the first stage was completed. As a result, an emulsion oi the waterdispersible polymer (A) having 17% solid content concentration was obtained.

The emulsion was sampled to determine the weight average molecular weight (Mw) in accordance with GPC in the undermentioned ■ ^■ condition. To the sampled emulsion, ammonia of the same equivalent amount as that of the carboxyl groups contained in the synthesized , . waterdispersible polymer (A) was added. After neutralization of the carboxyl groups, the condition of the emulsion was visually observed.. These measured results, the calculated Tg and the calculated acid value of waterdispersible polymer (A) are shown together in Tables 1 and 3.

Next, in succession, the waterdispersible polymer (B) was ^• . synthesized in accordance with the emulsion polymerization in the second stage. A pre-emulsion was prepared by blending sufficiently all of 54 parts of 25% aqueous solution of "Aqualon® KH-IO" (an anionic reactive surfactant manufactured by Daiichi Kogyo Seiyaku Co., Ltd.! being polyoxyethylene ■ alkylether sulfuric ester ammonium salt), 112.5 parts of deionized water, and the second stage monomers indicated as the identification number 1-2 in ^' Table 2 with each other. The resulting pre-emulsion wasidropped uniformly from a dropping funnel to the flask containing the emulsion of the ^■ <■ waterdispersible polymer (A) for 165 minutes. During the dropping, the inside temperature was maintained at 8O⁰C. After completing the- dropping the dropping funnel was washed with 10 parts of deionized water, and the washed water was added to the flask. Thereafter, the contents of the flask- were maintained at the same temperature for 30 minutes, and the " • polymerization in the second stage was completed; In succession,.10% of aqueous ammonia were added so as to be 0.9 equivalent amount with respect to 1 equivalent amount of the carboxyl groups in the whole monomers to continue stirring at 80°C for 60 minutes, after the contents were cooled dowi to room temperature, and then, the product was filtrated with a metal wire of 100 mesh to obtain an emulsion type resin composition ¹No¹. ^■ 1 of the - ' present invention. Furthermore, the calculated Tg of the water- dispersible polymer (B) obtained from the second stage monomers is shown together. in Tables 2 and 3. Synthesis Example 2

The initial reaction was conducted in accordance with the same ■ manner as that of the Synthesis Example 1 except that the^! monomers¹ used for the initial and the first stage reaction were that identified by No.- 2-1 in Table 1, the amount of the 20% aqueous solution of the Ηaitenόl® 18E¹' was changed to be 22.8 parts, and the amount of deionized water was changed to be 31.8 parts. In succession, the polymerization in the first stage was < ' ^ι conducted in accordance with the same manner as that of the Synthesis ' " Example 1 except that the remaining part of the pre-emulsion for the first^' ' stage was. dropped for 60 minutes. - The polymerization in the seeond'stage was carried out in accordance with the same manner as that of the ^! Synthesis Example 1 except that the monomers used for the second stage reaction were that identified by No. 2-2 in Table 2, the amount of 25% aqueous solution of "Aqualon® KH- 10" was 42 parts, the amount of deionized'water was 87!5' "^' parts, and the dropping period of time was 120 minutes. ^■ The resulting' ' . respective characteristic values are shown in Tables 1 to 3. • ^•<" ^'■ Synthesis Example 3 • ' The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 3-^' in Table 1, while the monomers used for the second stage reaction were that identified by No. 3-2 in Table 2. The resulting respective characteristic values are shown in Tables 1 to 3. Synthesis Example 4

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 4-^' in Table 1, while the monomers used for the second stage reaction were that identified by No. 4-2 in Table 2, respectively. The resulting respective characteristic values are shown in Tables 1 to 3. Synthesis Example 5

■ The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first 'stage reaction were that identified by No. 5-] in Table 1, while the monomers used for the second stage reaction were that identified by No. 5-2 in Table 2, respectively. The resulting respective characteristic values are shown in Tables' 1 to 3. Synthesis Example 6

The two-stage polymerization was conducted in accordance with' the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified^'by No. 6"] in Table 1, while the monomers used for the second stage reaction were that identified by No. 6-2 in Table 2, respectively. The resulting respective characteristic values are shown in Tables 1 to 3. This example is the one wherein an amount of the chain transfer agent is increased, whereby an Mw of the waterdispersible polymer (A) is decreased. Synthesis Example 7

The two-stage polymerization w^ras conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. T-^'. in Table 1, while the monomers used for the second stage reaction were that identified by No. 7-2 in Table 2, respectively. The resulting.respective ■ characteristic values are shown in Tables 1 to 3. This example is the one wherein an acid value of the waterdispersible polymer (A) is low. Synthesis Example 8

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 8¹] in Table 1, while the monomers used for the second stage reaction were 'that identified by No. 8-2 in Table 2, respectively. The resulting respective characteristic values are shown in Tables 1 to 3. This example 'is the one ' wherein an amount of the chain transfer agent is decreased, whereby an

of the waterdispersible polymer (A) is increased. Synthesis Example 9

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 9-1 in Table 1, while the monomers' used for the second stage reaction were that identified by No. 9-2 in Table 2, respectively. The resulting respective characteristic values are shown in Tables 1 to 3. This example is the one wherein an acid value of the waterdispersible polymer (A) is high. Synthesis Example 10

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 10" 1 in Table 4, while the monomers used for the second stage reaction were that identified by No. 10-2 in Table 5, respectively. The resulting respective characteristic values are shown in Tables 4 to 6. This example is the one wherein a Tg of the waterdispersible polymer (A) is high. Synthesis Example 11

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by No. 11-1 in Table 4, while the monomers "used for the second stage reaction were that identified by No. 11-2 in Table 5, respectively. The resulting respective characteristic values are shown in Tables 4 to 6. This example is the one^' ■ wherein a Tg of the water-dispersible polymer (A) is low. - < '

Synthesis Example 12

The two-stage polymerization was conducted in accordance with the same manner as that of the Synthesis Example 2 except that the monomers used for the initial and the first stage reaction were that identified by ¹No. 12-1 in Table 4, while the monomers used for the second stage reaction were that identified by No. 12-2 in Table δ, respectively. The resulting respective characteristic values are shown in Tables 4 to 6. Synthesis Example 13

The monomers used for the first stage reaction were that identified by No. 11-1 in Table 4, while the monomers used for the second stage reaction were that identified by No. 11-2 in Table 5, respectively. The _* polymerization reaction in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the amoun of the 20% aqueous solution of the "Haitenol® 18E" used in case of preparing the pre-emulsion was changed to be 3.8 parts, the amount of deionized wate] was changed to be 5.3 parts, the whole amount of the pre-emulsion was< added as a shot, and the polymerization was carried out for 30 minutes. Or one hand, in the second stage, the polymerization reaction in the second stage was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the amount of the 25% aqueous solution of the "Aqualon® KH" 10" used in case of preparing the pre-emulsion was made to be 57 parts, the amount of deionized water was made to be 118.8 parts, and the dropping period of time was made to be 180 minutes. The resulting respective characteristic values are shown in Tables 4 to 6. This example is the one wherein a ratio of the waterdispersible polymer (A) is small. Synthesis Example 14

The initial reaction was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the monomers used > for the initial and the first stage reaction were that identified by No. 14-1 in Table 4, the amount of the 20% aqueous solution of the "Haitenol® 18E" was changed to be 30.4 parts, and the amount of deionized water was changed to be 42.4 parts in case of preparing the pre-emulsion. In succession, the polymerization in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the remaining part o the pre-emulsion for the first stage was dropped for 80 minutes. The polymerization in the second stage was carried out in accordance with the same manner as that of the Synthesis Example 1 except that the monomers' used for the second stage reaction were that identified by No. 14^η2 in Table 5 45 parts of 20% aqueous solution of "Haitenol® 18E" was used in place 'of "Aqualon® KH-10", the amount of deionized water was made to be 66 part's,' and the dropping period of time was 100 minutes in case of preparing the pre-emulsion. The resulting respective characteristic values are shown in Tables 4 to 6. Synthesis Example lδ

The initial reaction was conducted in accordance with the same ' ⁽ ' manner as that of the Synthesis Example 1 except that the monomers used > for the initial and the first stage reaction were that identified by No.¹ 15-1 in Table 4, the amount of the 20% aqueous solution of the "Haitenol®' 18E" was changed to be 45.6 parts, and the amount of deionized water was'changed to be 63.6 parts in case of preparing the pre^:emulsion. In succession, the ¹ polymerization in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the- remaining part o the pre-emulsion for the first stage was dropped for 120 minutes. The polymerization in the second stage was carried'out in accordance with the ■ same manner as that of the Synthesis Example 1 except that the monomers used for the second stage reaction were that identified by No. 15-2 in Table 5. the amount of 25% aqueous solution of "Aqualon® KH-IO" was made to be 2^ parts, the amount of deionized water was made to be 50 parts, and the dropping period of time was 60 minutes in case of preparing the pre-emulsion. The resulting respective characteristic values are shown in Tables 4 to 6. This example is the one wherein a ratio of the waterdispersible polymer (A) is large. Synthesis Example 16

The initial reaction was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the monomers used for the initial and the first stage reaction were that identified by No. 2-2 in Table 2, the amount of the 20% aqueous solution of the "Haitenol© 18E" was replaced by 42 parts of 25% aqueous solution of "Aqualon® KH- 10", and the amount of deionized water was changed to be 87.5 parts in case of preparing the pre-emulsion. In succession, the polymerization in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the remaining part of the pre-emulsion for the first stage was dropped for 120 minutes. The polymerization in the second-stage was carried out in accordance with the same manner as that of the Synthesis Example 1 except that the monomers used for the second stage reaction wer« that identified by No. 2-1 in Table 1, the amount of 25% aqueous solution of "Aqualon® ICH-10" was replaced by 22.8 parts of 20% aqueous solution of "Haitenol® 18E", the amount of deionized water was made to be 31.8 parts,' and the dropping period of time was 60 minutes in case of preparing the pre-emulsion. The resulting respective characteristic values are shown in< Table 7. The Synthesis Example 16 is an example wherein the polymerization was conducted by reversing the order of the first stage and the second stage in the Synthesis Example 2, and in other words, the polymerization of the waterdispersible polymer (B⁾ is carried out before tha of the water-dispersible polymer (A⁾. Synthesis Example 17

The initial reaction was conducted in accordance with the same manner as that of the Synthesis Example 1 except that the monomers used for the initial and the first stage reaction were 1/3 amount of that identified by No. 8"1 in Table 1, the amount of the 20% aqueous solution of the "Haitenol® 18E" was changed to be 7.6 parts, and the amount of deionized water was changed to be 10.6 parts in case of preparing the pre-emulsion. In succession, the polymerization in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1 excep that the remaining part of the pre-emulsion for the first stage was dropped for 15 minutes, and in succession, the mixture was then aged for 30 minutes The resulting product corresponds to the water-dispersible'polymer (C), and the Mw thereof was 71,000.

The monomers used for the second stage reaction were that identifiec by No. 2-1 in Table 1, and to which 7.6 parts of 20% aqueous solution of the "Haitenol® 18E" and 31.8 parts of deionized water were added-to prepare a pre-emulsion. The pre-emulsion was dropped for 60 minutes, and then, the ' mixture was aged for 30 minutes. The resulting product corresponds to the water-dispersible polymer (A).

The monomers used for the third stage reaction were that- identified by No. 14-2 in Table 2, and to which 36 parts of 25% aqueous solution of the "Aqualon® KH-IO" and 75 parts of deionized water were added to prepare a pre -emulsion. The pre-emulsion was dropped for 100 minutes. The resulting product corresponds to the waterdispersible polymer (B).

In the three-stage polymerization, (A) : (B) : (C) is 30 : 60 : 10 (mass ratio). According to the three-stage polymerization, the emulsion type resir composition No. 17 was obtained. The resulting respective characteristic values are shown in Table 7. Synthesis Example 18

The same flask as that of the Synthesis Example 1 was charged with 220 parts of deionized water. A pre-emulsion was prepared by blending sufficiently all of 22.8 parts of 20% aqueous solution of "Haitenol® 18E", 31.5 parts of deionized water, and the monomers identified by No. 2-1 in Table 1 with each other. A dropping funnel was charged with the resulting pre-emulsion. Then, 42.3 parts of the pre-emulsion in the whole of them was added to the flask as a shot, and the temperature was elevated to 75°C with stirring while blowing moderately nitrogen gas thereinto. To the resulting mixture, 9.0 parts of 5% aqueous potassium persulfate were added to start the polymerization. In this case, the inside temperature of flask was elevated up to 8O⁰C and maintained for 10 minutes. < After completing the initial reaction, the remaining part of the pre-emulsion was dropped uniformly for 60 minutes while maintaining the inside temperature to 80°C. After completing the dropping, the dropping funnel was washed with 10 parts of deionized water, and the washed water was added to the flaski Thereafter, the contents of the flask were maintained at the same ' temperature for 30 minutes, then, 0.9 equivalent amount of aqueous ammonia was added thereto, and further, the stirring was continued at 8O⁰C for 60 minutes, thereafter the polymerization was completed. ' As a result, an emulsion 1 for blending use of the water dispersible polymer (A) was obtained wherein the Mw was 7500.

On one hand, another flask was charged with 213 parts of deionized water. Another pre-emulsion was prepared by blending sufficiently all of 4. parts of 25% aqueous solution of "Aqualon® KH-10", 87.5 parts of deionized water, and the monomers identified by No. 2-2 in Table 2 with each other, i dropping funnel was charged with the resulting pre-emulsion.- Then, 42.3 parts of the pre-emulsion in the whole of them was added to the flask as a shot, and the temperature was elevated to 7o°C with stirring while blowing moderately nitrogen gas thereinto. To the resulting mixture; 21.0 parts of 5% aqueous potassium persulfate were added to start the polymerization. In this case, the inside temperature of flask was elevated up' to 8O⁰C and maintained for 10 minutes. After completing the initial reaction, the remaining part of the pre-emulsion was dropped uniformly for 120 minutes while maintaining the inside temperature to 8O⁰C. After completing the dropping,- the dropping funnel was washed with 10 parts of deionize^'d water, and the washed water was added to the flask. Thereafter, the contents of the flask were maintained at the same temperature for 30 minutes, then, Oi equivalent amount of aqueous ammonia was added thereto, and further, the stirring was continued at 8O⁰C for 60 minutes, thereafter the polymerization was completed. As a result, an emulsion 2 for blending use of the ^■ • waterdispersible polymer (B) was obtained. The emulsion 1 and the emulsion 2 for blending use were mixed so as to be 30 ' 70 in the solid content ratio (mass ratio) to obtain the emulsion • type resin composition No. 18. The resulting respective characteristic values are shown in Table 7. Synthesis Example 19

The emulsion polymerization in the first stage was conducted in accordance with the same manner as that of the Synthesis Example 1. , Ten percent aqueous ammonia, the amount of which corresponds to 0.9 equivalent amount with respect to 1 equivalent amount of the carboxyl groups contained in all of the monomers in the first and the second stages, was prepared. Twenty percents of aqueous ammonia were added from the aqueous ammonia prepared to the flask as a shot after completing the emulsion polymerization in the first stage, and the mixture was stirred for • 15 minutes. The emulsion polymerization in the second stage was carried _' out in accordance with the same manner as that of the Synthesis Example 1 except that the remaining aqueous ammonia was added to the pre-emulsion of the monomers in the second stage and blended together,' and the mixture was dropped from the dropping funnel, whereby the emulsion type resin composition No. 19 of the present invention was obtained. The resulting respective characteristic values are shown in Table 7.

Moreover, a percent change of viscosity and pH in the case where the emulsion type resin composition No. 19 and the emulsion type resin composition No. 1 prepared in the Synthesis Example 1 are maintained ' > under the atmosphere of 50°C for one month is measured;;; As a result_/ .a < percent change of the viscosity/pH in the resin composition No. 1 was around 50%, and this level is practically no problem, while the resin composition No. 19 exhibited a percent change in the viscosity/pH of 20% or less, and thus, remarkably excellent temporal stability was achieved. Method for evaluating characteristic property [Measuring Method of Mw]

A solution obtained by dissolving an emulsion into tetrahydrofuran in such that a solid content of the polymer becomes 0.2% is used as a sample and Mw was measured by the use of a GPC ("HLL-8120GPC" manufactured by Tosoh Corporation) wherein a column is a coupled column of "TSKgel G5000HXL" and "TSKgel GMHXL" manufactured by Tosoh Corporation, anc a calibration curve was prepared by the use of a polystyrene standard sample. [Method for measuring the minimum film forming temperature (MFT)]

A film having 250 μm thickness (wet) is prepared with an applicator on a stainless steel flat plate with no groove, the minimum film forming temperature (⁰G) is measured within a measuring temperature range of froπ -5⁰C to +3O⁰C by using a MFT tester ("TP-801 LT type" manufactured by Tester Industry Co., Ltd.). The presence of cracks is judged by visual observation in accordance with JIS K6828-2 (2003⁾.

[Method for evaluating hardness of emulsion film and coating film of coating material by means of Koenig hardness meter]

A film having 250 μm (wet^; 40 to 60% solid content concentration) thickness of the emulsion type resin composition is prepared on. a glass plate by means of an applicator, the film is allowed to stand at 23⁰C for 24^"hours, and then, the plate coated with the film is set in the above-described >> pendulum type hardness meter wherein a measurement initial angle is to be 6°, and a reciprocating number of cycles of the pendulum (a tungsten carbide steel ball) until a measurement finished angle thereof comes to be lower thar 3° is determined as Koenig hardness (cycles). In the case when tacks appear on the coating film, the pendulum stops. Accordingly, -the larger number of cycles means the harder film, so that the performance of the resulting film is good. The evaluation standard is as follows. . @: 11 or more cycles, O^: o to 10 cycles, Δ: 3 to 4 cycles, X : 0 to 2 cycles. [Method for measuring water absorption rate]

The emulsion type resin composition of the present invention is ' applied to a releasing paper so as to obtain a film having 250 μm dry film thickness, and the emulsion type resin composition is dried at 23⁰C for 24 hours. The resulting film is cut out into a proper size (around 5 cm x 5 cm) the film cut out after it is precisely weighed is immersed into tap water at 23⁰C for 24 hours, it is then taken out and water drops are removed, and it is precisely weighed. The water absorption rate (% by mass) is determined in accordance with a formula 100 x (the mass of a sample after immersion ^■ the mass of the sample before immersion)/the mass of the sample before immersion wherein an average value in case of n = 3 is determined. Furthermore, the evaluation standard is as follows. ©^: less than 15%, O^: 15% or more to less than 20%, Δ: 20% or more to less than 25%, X ; 25% or more. [Preparation of coating material]

First, a paste for coating material use was prepared by mixing 4.0 parts of "Demol ® EP" (manufactured by Kao Corporation; a particular kind^" of polycarboxylic acid type high-molecular surfactant) as a'pigment dispersant, 3.4 parts of "Emulgen ® LS106 (manufactured by Kao Corporation; a nonionic surfactant! polyoxyethylene alkylene ether), 0.7 par of "Nopco 8034L"(manufactured by San Nopco Ltd.) as an antifoaming agent and 67.2 parts of "Tipaque® CR-95" (manufactured by Ishihara Sangyo Kaisha Ltd.) as a white pigment (titanium dioxide) with 18.1 parts of deionized water.

Then, 200 parts (wet) of each of the emulsion type resin compositions synthesized in the respective Synthesis Examples were taken up, and to which 94.1 parts of the above-described paste, and 1.0 part of the "Nopco 8034L"-were added, and the mixture was stirred sufficiently to prepare a white coating material. The resulting respective coating materials ^"were evaluated with respect to MFT (⁰C), and coating film hardness¹ in accordance with the_Eabove-described manners. [Water resistance of coating film]

"DAN clear sealer" (manufactured by Nippon Paint Co., Ltd.; chlorinated-rubber-base) was brush-coated on a "Nozawa 'Flexible Sheet" (slate sheet-manufactured by Nozawa Company; JIS K5410) so as to obtain 100 g/m² coating weight after drying it, then it was dried at 23°C for 24 hours thereafter the product was immersed into water of 23⁰C, and the coating filrc condition was visually observed after the lapse of 7 days. No abnormal condition on the coating film is represented by @, less than 5% area ratio of blistering or peeling off is represented by O, less than 20%' area ratio of blistering or peeling off is represented by Δ, and blistering or peeling off appearing on the whole surface of the coating film is represented by X . ' It is to be noted that the names of the respective monomers are abbreviated as follows in the Tables, and the numerical values on the right lines correspond to values of Tg (K) described in the Polymer Handbook.

MMA : methyl methacrylate 378K

2EHA: 2-ethylhexyl acrylate 203K

St : styrene 373K

CHMA: cyclohexyl methacrylate 356K

IBMA: isobornyl methacrylate 453K

NVP : N"vinjd pyrrolidone 448K

AA : acrylic acid 368K

MAA : methacrylic acid 403K

HEMA: 2-hydroxyethyl methacrylate 328K

HALS: "ADK STAB ® LA-87", manufactured by ADEKA Corporation 4-meth acryloyloxy2,2,6,6-tetramethyl piperidine) 403K

Table 1

Table 2

V

Table 3

Table 4

Table 5

- 0

Table 6 -

OO

- 0

Table 7 ;

CD

-

INDUSTRIAL APPLICABILITY

According to the present invention, an emulsion type resin composition for coating material use having the minimum film formability' (MFT⁾ of O⁰C or lower can be provided without incorporating a volatile organic compound (VOC) thereinto. Since a coating film obtained from the emulsion type resin composition has a good hardness and water absorption rate, it is suitable for applying, for example, to coating materials used for exterior and interior coating for buildings and plants.

Claims

1. An emulsion type resin composition having the minimum film forming temperature of O⁰C or lower and containing substantially no volatiL organic compound, wherein a Koenig hardness of a film obtained by drying the emulsion type resin composition at 23⁰C for 24 hours is five cycles or more, and the water absorption rate thereof is less than 20% by mass.

2. An emulsion type resin composition comprising a water- dispersible polymer (A) having a glass transition temperature of 50 tc 15O⁰C and a weight average molecular weight of 5,000 to 50,000. ■

3. The emulsion type resin composition according to claim 2, wherein an acid value of the waterdispersible polymer (A) is 20 to 70.'

4. The emulsion type resin composition according to claim 2 or 3; further comprising a waterdispersible polymer (B) having a glass transitior temperature of "40 to O⁰C.

5. The emulsion type resin composition according to claim 4, wherein the waterdispersible polymer (A) is 10 to 50% by mass, and the i waterdispersϊble polymer (B) is 90 to 50% by mass, when the total of the waterdispersible polymer (A) and the waterdispersible polymer (B) is 100% by mass.

6. The emulsion type resin composition according to claim 4, furthei comprising a waterdispersible polymer (C) having a weight average molecular weight of more than 50,000, wherein the water- dispersible polymer (A) is 10 to 50% by mass, the waterdispersible polymer (B) is 85 to 20% by mass, and the water- dispersible polymer (C) is 5 to 30% by mass, when the total of the water-dispersible polymer (A), the water-dispersible polymer (B), and the water-dispersible polymer (C) is 100% by mass.

7. A coating material comprising the emulsion type resin composition according to any one of claims 1 to 6.

8. A coating film being obtained from the coating material according to claim 7.

9. A method for manufacturing an emulsion type resin composition which comprises a water-dispersible polymer (A) having a glass transition temperature of 50 to 15O⁰C, a weight average molecular weight of 5,000 to 50,000, and an acid value of 20 to 70, a water-dispersible polymer (B) having a glass transition temperature of -4O⁰C to O⁰C, and a neutralizing agent; in a multistage emulsion polymerization comprising: polymerizing a raw material monomer of the water-dispersible polymer (A) in the first stage in a reaction vessel, subsequently polymerizing a raw material monomer of the ⁱ ' ' water-dispersible polymer (B) in the second stage in the same reaction vesse and adding 0 to 50% by mass of the neutralizing agent of 100% by mass of the neutralizing agent corresponding, to 0.5 to 1.5 equivalent amoum with respect to 1 equivalent amount of the amount of the carboxyl groups contained in the waterdispersible polymer (A) and the water-dispersible polymer (B) to the reaction vessel as a shot after the polymerization in the first stage, and dropping 50 to 100% by mass of the remaining neutralizing agent into the reaction vessel during the polymerization of the raw material ' ' monomer in the second stage.