JPH1149956A - Aqueous curing resin composition and silicone acrylic emulsion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous composition capable of forming a membrane showing the same water resistance, heat resistance and mechanical strength as the one obtained from the solvent system by mixing an emulsion comprising an aqueous medium, an alkenyl group-containing acrylic resin, a hydroxyl group- containing organopolysiloxane and an anionic surfactant with a hydroxylation catalyst. SOLUTION: As the hydroxyl group-containing organopolysiloxane is used the one represented by the formula (wherein R<1> is 1-6C alkyl, phenyl or phenethyl; R<2> is H or methyl; X is 3-(meth)acryloyloxypropyl; 0<=a<=10; when R<2> is H, 0<=b<=30; when R<2> is methyl, 2<=b<=30; and 0<=c<=3). As the acrylic resin is preferred a copolymer prepared by using an alkenyl group-containing acrylic monomer selected from allyl acrylate and 3-methyl-3-butenyl (meth) acrylate. As the anionic surfactant is preferred the one containing an alkenyl group.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin composition and an emulsion, and more particularly to an aqueous curable resin composition and a silicone acrylic emulsion.

[0002]

2. Description of the Related Art As a curable resin composition capable of forming a film excellent in water resistance, weather resistance and mechanical strength,
For example, the one described in JP-A-3-277645 is known. This curable resin composition is an acrylic resin having at least two alkenyl group-containing groups in one molecule,
It contains a polyester resin or an epoxy resin, an organohydrogenpolysiloxane having at least two hydrosilyl groups in one molecule, and a platinum catalyst.

[0003]

Since the above-mentioned curable resin composition is a so-called solvent-based resin composition, a solvent must be used in principle when used. However, from the viewpoint of preventing environmental pollution, the use of a solvent-based resin composition is being avoided, so that the curable resin composition described above has limited applicability in the future. For this reason, there is a demand for an aqueous curable resin composition instead of a solvent system,
A material capable of forming a film capable of exhibiting the same properties as those formed by a solvent-based curable resin composition has not yet been realized.

[0004] An object of the present invention is to provide a water-based curable resin composition having a film exhibiting the same water resistance, weather resistance, heat resistance and mechanical strength as those formed by a solvent-based curable resin composition. To be able to form.

[0005] Another object of the present invention is to realize an emulsion which can be used for such an aqueous curable resin composition.

[0006]

The aqueous curable resin composition according to the present invention comprises an aqueous medium, an acrylic resin having at least two alkenyl groups in one molecule, and an average composition formula (1) shown below. A silicone acrylic emulsion containing an organopolysiloxane compound having at least two hydrosilyl groups in one molecule and an anionic surfactant, and a hydrosilylation reaction catalyst.

[0007]

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In the formula, R ¹ represents an alkyl group having 1 to 6 carbon atoms, a phenyl group or a phenethyl group. R ² represents hydrogen or a methyl group. X is a 3-acryloyloxypropyl group or 3
-Represents a methacryloyloxypropyl group. a,
b and c are respectively 0 ≦ a ≦ 10, 0 ≦ b ≦ 30 when R ² is hydrogen, ² ≦ b ≦ 30 when R ² is a methyl group,
And an integer in the range of 0 ≦ c ≦ 3.

Here, the acrylic resin contained in the silicone acrylic emulsion is, for example, allyl acrylate, allyl methacrylate, 3-methyl-3-acrylate.
A copolymer prepared using at least one alkenyl group-containing acrylic monomer selected from the group consisting of butenyl and 3-methyl-3-butenyl methacrylate.

The anionic surfactant has, for example, an alkenyl group.

Further, the silicone acrylic emulsion is, for example, 30 to 99 parts by weight of an acrylic resin, 1 to 70 parts by weight of an organopolysiloxane compound and 0.1 to 15 parts by weight of an anionic surfactant. Contains.

[0012] The silicone acrylic emulsion of the present invention comprises an aqueous medium, an acrylic resin having at least two alkenyl groups in one molecule, a hydrosilyl group represented by the above average composition formula (1) and one molecule. And an anionic surfactant.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Silicone Acrylic Emulsion A silicone acrylic emulsion contained in the aqueous curable resin composition of the present invention comprises an aqueous medium, an acrylic resin,
It contains an organopolysiloxane compound and an anionic surfactant.

(Aqueous Medium) The aqueous medium used in the present invention is not particularly limited as long as it is used for a general resin emulsion, and is usually water.

(Acrylic Resin) The acrylic resin used in the present invention has at least two alkenyl groups in one molecule. As such an acrylic resin, as an alkenyl group, for example, an allyl group, a 2-butenyl group, a 3-methyl-3-butenyl group, a cyclohexenylmethyl group, a 2-methyl-2-propenyl group, a 3-heptenyl group, An acrylic resin containing a 4-hexenyl group or the like in a side chain is used. Such an acrylic resin having an alkenyl group can be easily prepared by polymerizing an alkenyl group-containing acrylic monomer and another acrylic monomer according to a known method.

The alkenyl group-containing acrylic monomer used here is generally a linear or cyclic alkenyl group-containing alcohol acrylate or methacrylate. Specifically, allyl acrylate, allyl methacrylate, 2-butenyl acrylate, 2-butenyl methacrylate, 3-methyl-3-butenyl acrylate, 3-methyl-3-butenyl methacrylate, cyclohexenylmethyl acrylate , Cyclohexenylmethyl methacrylate, 2-methyl-2-propenyl acrylate,
1: 1 of 2-methyl-2-propenyl methacrylate, 3-heptenyl acrylate, 3-heptenyl methacrylate, 4-hexenyl acrylate, 4-hexenyl methacrylate, 2-hydroxyethyl methacrylate and vinylcyclohexene monoepoxide (For example, "Cyclomer MF-40" manufactured by Daicel Chemical Industries, Ltd.)
1 ″). Further, a silicone monomer represented by the following general formula, that is, a vinyl-terminated polydimethylsiloxypropyl acrylate or a vinyl-terminated polydimethylsiloxypropyl methacrylate can also be used. When these alkenyl group-containing acrylic monomers represented by the formula (1) are used, an effect of improving the compatibility with the hydrosilyl group-containing organopolysiloxane compound can be expected.

[0017]

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On the other hand, other acrylic monomers include:
For example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, t-butyl acrylate,
T-butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, lauryl acrylate, lauryl methacrylate, phenyl acrylate, phenyl methacrylate, benzyl acrylate, benzyl methacrylate, 2-hydroxyethyl acrylate, methacryl 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 2-hydroxyethyl acrylate or 2-hydroxyethyl methacrylate and ε- Adduct with caprolactone (eg, “Placcel FM-1” manufactured by Daicel Chemical Industries, Ltd.), glycidyl acrylate,
Glycidyl methacrylate, 3-trimethoxysilylpropyl acrylate, 3-trimethoxysilylpropyl methacrylate, 3-dimethoxymethylsilylpropyl acrylate, 3-dimethoxymethylsilylpropyl methacrylate, acrylamide-2-methylpropanesulfonic acid,
Acid phosphoxypropyl methacrylate, tributyltin acrylate, tributyltin methacrylate, acrylamide, methacrylamide, acryloyl isocyanate, methacryloyl isocyanate, acrylic acid 2
-Isocyanate ethyl, 2-isocyanate ethyl methacrylate, and silicone macromonomer (for example, "X-22-174DX" manufactured by Shin-Etsu Chemical Co., Ltd.).

In addition, in addition to the above-mentioned alkenyl group-containing acrylic monomer and the above-mentioned other acrylic monomer, these monomers may be used as a monomer for producing the above-mentioned acrylic resin having at least two alkenyl groups. Other copolymerizable monomers can be used in combination. Such other monomers include, for example, styrene, α-methylstyrene, itaconic acid, maleic acid, vinyl acetate, allyl acetate, vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinylmethyldiethoxysilane , N-cyclohexylmaleimide, N-phenylmaleimide and the like.

Preferred acrylic resins prepared using the above-mentioned alkenyl group-containing acrylic monomer and other acrylic monomers described above have high reactivity between the alkenyl group and the hydrosilyl group contained therein,
As a result, it is possible to form a film having high mechanical strength, from the group consisting of allyl acrylate, allyl methacrylate, 3-methyl-3-butenyl acrylate and 3-methyl-3-butenyl methacrylate. It is a copolymer prepared using at least one selected alkenyl group-containing acrylic monomer.

The acrylic resin having at least two alkenyl groups as described above may be used in combination of two or more.

(Organopolysiloxane Compound) The organopolysiloxane compound used in the present invention has at least two hydrosilyl groups (SiH groups) in one molecule and is represented by the following average composition formula (1). It is what is done.

[0023]

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In the average composition formula (1), R ¹ represents an alkyl group having 1 to 6 carbon atoms, a phenyl group or a phenethyl group. R ² represents hydrogen or a methyl group. Further, X represents a 3-acryloyloxypropyl group or a 3-methacryloyloxypropyl group.

Further, a, b and c in the average composition formula (1) are respectively 0 ≦ a ≦ 10 and 0 ≦ b ≦ R ² is hydrogen.
≦ 30, 2 ≦ b ≦ 30 when R ² is a methyl group, and 0
It is an integer in the range of ≦ c ≦ 3. If a exceeds 10, the organopolysiloxane compound does not show sufficient water solubility. When b exceeds 30, the organopolysiloxane compound does not show sufficient water solubility. Further, when c exceeds 3, a stable silicone acrylic emulsion may not be obtained.

The type of R ² and the numerical values of a, b and c are selected so that the organopolysiloxane compound represented by the average composition formula (1) has at least two hydrosilyl groups. For example, 2 in the average composition formula (1)
When two R ² are both methyl groups, b is 2 ≦ b ≦ 30
Is an integer in the range

Specific examples of the organopolysiloxane compound represented by the average composition formula (1) include, for example, the following average composition formulas (a), (b), (c), (d),
(E), (f) and (g). Note that these organopolysiloxane compounds are commercially available and can be easily obtained.

[0028]

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[0029]

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The above-mentioned hydrosilyl group-containing organopolysiloxane compounds may be used in combination of two or more.

(Anionic Surfactant) The anionic surfactant used in the present invention is a known anionic surfactant usually used for preparing an emulsion, and examples thereof include alkylbenzenesulfonic acid and a salt thereof. , Alkyl ether sulfates, alkyl phenyl ether sulfates, sulfosuccinates and ether sulfonates.

However, such an anionic surfactant preferably contains an alkenyl group. When an alkenyl group-containing anionic surfactant is used, the anionic surfactant hardly remains as a simple substance in a film formed using the composition of the present invention, so that the water resistance of the film is further increased. be able to. The alkenyl group-containing anionic surfactant includes the following (h) to (o)
Can be mentioned. Note that n in the equation
And m represent an integer of 2 or more, and R represents a hydrocarbon group having 6 to 18 carbon atoms.

[0033]

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(Blending Ratio) The preferred blending ratio of the above-mentioned acrylic resin, organopolysiloxane compound and anionic surfactant constituting the silicone acrylic emulsion used in the present invention is usually 30 to 99% by weight of the acrylic resin. Parts (more preferably 40 to 80 parts by weight), the organopolysiloxane compound is 1 to 70 parts by weight (more preferably 20 to 60 parts by weight), and the anionic surfactant is 0.1 to 15 parts by weight (more preferably). 1 to
10 parts by weight).

When the amount of the acrylic resin is less than 30 parts by weight or when the amount of the organopolysiloxane compound is more than 70 parts by weight, there is a possibility that the stability of the silicone acrylic emulsion with time is reduced. On the other hand, acrylic resin is 9
When the amount exceeds 9 parts by weight or when the amount of the organopolysiloxane compound is less than 1 part by weight, the water resistance, weather resistance and heat resistance of the film obtained from the composition of the present invention may be reduced. When the amount of the anionic surfactant is less than 0.1 part by weight, it becomes difficult to obtain a target silicone acrylic emulsion by emulsion polymerization described later. Conversely, if the amount exceeds 15 parts by weight, the water resistance, weather resistance, heat resistance and mechanical strength of the film obtained from the composition of the present invention may be reduced.

However, the mixing ratio of the organopolysiloxane compound to the acrylic resin is such that the hydrosilyl group contained in the organopolysiloxane compound is 0.5 to 4 times the mole of the alkenyl group contained in the acrylic resin, and particularly preferably 0.1 to 4 times. 8
It is preferable to set the ratio so as to be 1.5 times the mole. When this ratio is outside this range, the alkenyl group or hydrosilyl group remaining in the unreacted state reacts with moisture or contaminants, or is affected by ultraviolet rays, and as a result, is contained in the composition of the present invention. In some cases, the film obtained from the resin component or the composition of the present invention is easily deteriorated.

(Production Method) The above-mentioned silicone acrylic emulsion can be produced according to a usual emulsion polymerization method. For example, the above-mentioned various monomers for synthesizing the above-mentioned acrylic resin, a polymerization initiator for polymerizing the monomers, a mixture of an organopolysiloxane compound and an anionic surfactant are mixed in heated water with stirring. It can be produced by dropping at a constant speed over a period of time (for example, 3 hours). Incidentally, the polymerization reaction here,
Usually, it is preferably carried out under normal pressure, and the reaction temperature is preferably set at 60 to 90 ° C.

Examples of the polymerization initiator include inorganic peroxides such as ammonium persulfate and potassium persulfate; organic peroxides such as benzoyl peroxide and tert-butyl peroxypivalate; Azo initiators such as' -azobisisobutyronitrile, 2,2'-azobis-2-methylbutyronitrile and dimethyl-2,2'-azobisisobutyrate can be used. The amount of the polymerization initiator used can be appropriately set, but is usually set to 0.5 to 5 parts by weight.

When a silicone acrylic emulsion is produced, a molecular weight modifier can be used for the purpose of adjusting the molecular weight of the acrylic resin. As the molecular weight modifier, for example, a chain transfer agent such as mercaptans and 2,4-diphenyl-1-pentene can be used.

When a more stable silicone acrylic emulsion is produced, it is effective to use a PH buffer solution, and it is also possible to employ a pre-emulsification method. In this case, first, a mixture of the above-described various monomers, a polymerization initiator, an organopolysiloxane compound, an anionic surfactant and water for synthesizing the above-mentioned acrylic resin is prepared, and this mixture is stirred at a high speed. To prepare a pre-emulsion by emulsification. Thereafter, emulsion polymerization is carried out while dropping the pre-emulsion into heated water at a constant speed.

The average particle size of the silicone acrylic emulsion produced by the above method is preferably 5 μm or less. When the average particle size is 5 μm or more, sedimentation is liable to occur, and it becomes difficult to obtain a stable aqueous curable resin composition.

Hydrosilylation Reaction Catalyst The hydrosilylation reaction catalyst used in the present invention is an addition reaction (hydrosilylation reaction) between the hydrosilyl group of the organopolysiloxane compound contained in the silicone acrylic emulsion and the alkenyl group of the acrylic resin. Reaction).

As the hydrosilylation reaction catalyst used here, a transition metal of Group VIII or a compound thereof, for example, a complex of platinum, palladium, rhodium and ruthenium can be used. More specifically, Pt
_{Cl 4, H 2 PtCl 6 ·} 6H 2 O, Pt- vinylsiloxane complexes (e.g., Ptn (ViMe ₂ SiOSiMe ₂
Vi) m), a Pt-phosphine complex (for example, Pt (P
Ph) ₄ ), a Pt-olefin complex (for example, PtCl
_{2 (cod)), Pt (} acac) 2, trans- or _{cis- [PtCl 2 (NH 2 Pr} ) 2], PdCl
₂ (PPh ₃ ) ₂ , PdCl ₂ (PhCN) ₂ , RhCl ₂
(PPh ₃ ) ₃ , [RhClcod] ₂ , Ru (cpd)
₂ etc. and other known hydrosilylation reaction catalysts can be exemplified. The above-mentioned hydrosilylation reaction catalyst comprises 2
More than one species may be used in combination. In the above example,
Me is a methyl group, Vi is a vinyl group, Ph is a phenyl group,
Pr is a propyl group, cod is cyclooctadiene, ac
ac indicates acetyl acetate, and cpd indicates cyclooctadiene. Further, n and m are integers.

Mixing Ratio In the aqueous curable resin composition according to the present invention, the amount of the hydrosilylation reaction catalyst is preferably set to 5 to 1,000 ppm based on 100 parts by weight of the solid content of the silicone acrylic emulsion. More preferably, it is set to 500 ppm. When the amount is less than 5 ppm, the composition of the present invention may not show sufficient curability. On the other hand, if it exceeds 1,000 ppm, a uniform curing reaction may not easily occur.

Incidentally, the aqueous curable resin composition of the present invention comprises:
It can be adjusted by adding a predetermined amount of the above-mentioned hydrosilylation reaction catalyst to the above-mentioned silicone acrylic emulsion and mixing them.

Use of the Aqueous Curable Resin Composition In the aqueous curable resin composition of the present invention, the hydrosilyl group contained in the organopolysiloxane compound of the silicone acrylic emulsion and the alkenyl group contained in the acrylic resin are subjected to a hydrosilylation reaction catalyst. Causes an addition reaction (hydrosilylation reaction). Thereby, the resin component contained in the silicone acrylic emulsion is cured, and a cured film is obtained.

The aqueous curable resin composition of the present invention forms a film capable of exhibiting the same water resistance, weather resistance, heat resistance and mechanical strength as a film made of a conventional solvent-based curable resin composition. Therefore, for example, it can be used as a coating material, various protective coating materials, an electric insulating material, a molding resin, and the like.

The aqueous curable resin composition of the present invention may contain pigments and various additives, if desired. However, additives which inhibit the hydrosilylation reaction, such as nitrogen, sulfur, phosphorus, etc. It is preferred to avoid using those containing elements such as arsenic.

[0049]

Example 1 (Production of silicone acrylic emulsion) 43 parts by weight of an organopolysiloxane compound represented by the above average composition formula (c), 3-methyl-3-methacrylate
28.5 parts by weight of butenyl, n-butyl methacrylate 2
6.2 parts by weight, 2.3 parts by weight of methacrylic acid, dimethyl-
0.7 parts by weight of 2,2'-azobisisobutyrate, 4 parts by weight of a surfactant represented by the above formula (h) (where n = 10) and 200 parts by weight of water were dispersed using a dispersing machine. And stirred at 5,000 rpm for 10 minutes to obtain a pre-emulsion.

Next, a reaction vessel equipped with a condenser, a stirrer, a nitrogen inlet tube and a dropping funnel was prepared.
00 parts by weight of water was charged and heated to 80 ° C. And
304.7 parts by weight of the obtained pre-emulsion was added to 4 parts of this water.
The solution was added dropwise over 3 hours under stirring at 00 rpm. afterwards,
The solution was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion.

The obtained silicone acrylic emulsion had a nonvolatile content of 19.2% by weight (120 ° C., 30 minutes) and an average particle size of 0.68 μm. Also,
Measurement of the infrared absorption spectrum for each of the non-volatile component after the immediately silicone acrylic emulsion and the fabrication thereof stored for 2 months at room temperature, around 3070 cm ^-1 based on 2150 cm ^-1 and alkenyl groups based on the hydrosilyl group in either case Characteristic absorption was confirmed.

Example 2 (Silicone acrylic emulsion)
Organopolysiloxane compound 15 parts by weight represented by the emission of manufacture) above average composition formula (g), methacrylic acid 3-methyl-3-
15 parts by weight of butenyl, 57.7 parts by weight of methyl methacrylate, 2.3 parts by weight of methacrylic acid, dimethyl-2,2'-
0.7 parts by weight of azobisisobutyrate, the above formula (h)
8 parts by weight of a surfactant represented by the following formula (where n = 10) and 200 parts by weight of water were subjected to 5,000 r using a dispersing machine.
The mixture was stirred at pm for 10 minutes to obtain a pre-emulsion.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 200 parts by weight of water and the above-mentioned formula (h) were added thereto.
And 2 parts by weight of a surfactant represented by the following formula (where n = 10), and heated to 80 ° C. Then, in this aqueous solution, 310.7 parts by weight of the obtained pre-emulsion was
The mixture was added dropwise over 3 hours while stirring at pm. Then 80 ° C
For 4 hours to obtain a milky white silicone acrylic emulsion.

The obtained silicone acrylic emulsion had a non-volatile content (120 ° C., 30 minutes) of 18.2% by weight and an average particle size of 0.42 μm. Also,
Measurement of the infrared absorption spectrum for a non-volatile content of immediately after production silicone acrylic emulsion, characteristic absorption around 3070 cm ^-1 based on 2150 cm ^-1 and alkenyl groups based on the hydrosilyl group was confirmed.

Example 3 (Silicone acrylic emulsion)
Organopolysiloxane compound 43 parts by weight represented by the emission of manufacture) above average composition formula (c), allyl 28 parts by weight of methacrylic acid, 2-ethylhexyl 29 parts by weight of methacrylic acid, dimethyl-2,2'-Azobisuisobuchi 0.7 parts by weight of a surfactant, a surfactant represented by the above formula (h) (where n =
10 parts) and 4 parts by weight of water and 80 parts by weight of water were stirred at 5,000 rpm for 10 minutes using a disperser to obtain a pre-emulsion.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 70 parts by weight of water was charged into the reaction vessel and heated to 80 ° C. Then, in this water, the obtained pre-emulsion 1
84.7 parts by weight was added dropwise over 3 hours while stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion. The obtained silicone acrylic emulsion has a nonvolatile content of (120
C., 30 minutes) was 38.2% by weight, and the average particle size was 0.53 μm.

Example 4 (Silicone acrylic emulsion)
Organopolysiloxane compound 15 parts by weight represented by the emission of manufacture) above average composition formula (g), methacrylic acid 3-methyl-3-
15 parts by weight of butenyl, n-butyl methacrylate 57.7
Parts by weight, 2.3 parts by weight of methacrylic acid, dimethyl-2,
0.7 parts by weight of 2'-azobisisobutyrate, a surfactant represented by the above formula (h) (provided that n = 20)
1 part by weight and 200 parts by weight of water were added to
The mixture was stirred at 00 rpm for 10 minutes to obtain a pre-emulsion.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 200 parts by weight of water was charged into the reaction vessel at 80 ° C.
Heated. Then, 304.7 parts by weight of the obtained pre-emulsion was dropped into this water over 3 hours while stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion. The obtained silicone acrylic emulsion has a nonvolatile content of (120
C., 30 minutes) was 18.5% by weight, and the average particle size was 1.2 μm.

Example 5 (Silicone acrylic emulsion)
Production of styrene) 60 parts by weight of the organopolysiloxane compound represented by the above average composition formula (c), 25 parts by weight of allyl methacrylate, 15 parts by weight of 2-ethylhexyl methacrylate, dimethyl-2,2'-azobisisobutyi 3.5 parts by weight of a surfactant, a surfactant represented by the above formula (h) (where n =
10 parts) and 4 parts by weight of water and 80 parts by weight of water were stirred at 5,000 rpm for 10 minutes using a disperser to obtain a pre-emulsion.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 70 parts by weight of water was charged into the reaction vessel and heated to 80 ° C. Then, in this water, the obtained pre-emulsion 1
84.7 parts by weight was added dropwise over 3 hours while stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion. The obtained silicone acrylic emulsion has a nonvolatile content of (120
C., 30 minutes) was 39.7% by weight, and the average particle size was 0.44 μm.

Example 6 (Silicone acrylic emulsion)
Preparation of the compound) 60 parts by weight of the organopolysiloxane compound represented by the above average composition formula (b), 3-methyl-3-methacrylate
8 parts by weight of butenyl, 50 parts by weight of methyl methacrylate, 15 parts by weight of n-butyl acrylate, 20 parts by weight of n-butyl methacrylate, 4 parts by weight of 2,4-diphenyl-1-pentene, 1.0 part by weight of benzoyl peroxide Part, the above formula (h)
2 parts by weight of a surfactant represented by the following formula (where n = 10), 2 parts by weight of a nonionic surfactant represented by the following formula, and 80 parts by weight of water were subjected to 5,000 rpm using a dispersing machine.
For 10 minutes to obtain a pre-emulsion.

[0062]

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Next, a reaction vessel similar to that used in Example 1 was prepared, and 70 parts by weight of water was charged therein and heated to 80 ° C. Then, in this water, the obtained pre-emulsion 1
85 parts by weight were added dropwise over 3 hours while stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion. The obtained silicone acrylic emulsion has a nonvolatile content (120 ° C., 3
0 min) was 39.5% by weight, and the average particle size was 0.62.
μm.

Comparative Example 1 (Silicone acrylic emulsion)
Implementation down of production) in place of the surfactant represented by the above formula (h) Example 6
A pre-emulsion was obtained by operating in the same manner as in Example 2 except that the nonionic surfactant used in Example 2 was used. When the obtained pre-emulsion was dropped into water heated under the same conditions as in Example 2 with stirring, the reaction system aggregated when 1/3 of the pre-emulsion was dropped, and the desired silicone acrylic emulsion was obtained. Could not get.

Comparative Example 2 (Production of Acrylic Emulsion) 15 parts by weight of 3-methyl-3-butenyl methacrylate, 57.7 parts by weight of methyl methacrylate, 2.3 parts by weight of methacryl, dimethyl-2,2'-azobis 0.7 parts by weight of isobutyrate, 6 parts by weight of a surfactant represented by the above formula (h) (where n = 10) and 200 parts by weight of water are used at 5,000 rpm for 10 minutes using a dispersing machine. The mixture was stirred to obtain a pre-emulsion.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 200 parts by weight of water was charged into the reaction vessel at 80 ° C.
Heated. Then, 275.7 parts by weight of the obtained pre-emulsion was dropped into this water over 3 hours while stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a slightly turbid acrylic emulsion. The obtained acrylic emulsion has a nonvolatile content of 1 (120 ° C., 30 minutes).
It was 6.4% by weight, and the average particle size was 90 nm.

Comparative Example 3 (Silicone acrylic emulsion)
Preparation of the compound) 80 parts by weight of the organopolysiloxane compound represented by the above average composition formula (c), 3-methyl-3-methacrylate
Butenyl 10 parts by weight, n-butyl methacrylate 10 parts by weight, dimethyl-2,2'-azobisisobutyrate 0.
7 parts by weight, 8 parts by weight of the surfactant represented by the above formula (h) (where n = 10) and 200 parts by weight of water were stirred at 5,000 rpm for 10 minutes using a disperser, and pre-emulsified. I got something.

Next, a reaction vessel similar to that used in Example 1 was prepared, and 200 parts by weight of water was charged into the reaction vessel at 80 ° C.
Heated. Then, into this water, 310.7 parts by weight of the obtained pre-emulsion was dropped over 3 hours under stirring at 400 rpm. Thereafter, the temperature was kept at 80 ° C. for 4 hours to obtain a milky white silicone acrylic emulsion. The obtained silicone acrylic emulsion has a nonvolatile content of (120
C., 30 minutes) is 19.5% by weight, and the average particle diameter is 1
2.3 μm. In this silicone acrylic emulsion, the ratio of the hydrosilyl group of the organopolysiloxane compound to the alkenyl group of the acrylic resin (hydrosilyl group / alkenyl group) was 8.1 / 1.

Examples 7 to 12 (of the aqueous curable resin composition
Preparation) butyl cellosolve 10g added as coalescents for each 100 g (solid content) of a silicone acrylic emulsion obtained in Examples 1 to 6, further aqueous chloroplatinic acid _{(H 2 PtCl 6 · 6H 2} O in An aqueous curable resin composition was obtained by adding 100 ppm of a 33% by weight aqueous solution. The obtained aqueous curable resin composition was applied to an aluminum base material so as to have a thickness of about 15 μm, and was thermally cured at 100 ° C. for 30 minutes to form a cured coating film.

Example 13 (Preparation of aqueous curable resin composition)
Manufactured) Silicone acrylic emulsion 1 obtained in Example 1
10 g of butyl cellosolve as a film-forming aid was added to 00 g (in terms of solid content), and a chloroplatinic acid aqueous solution (H ₂
PtCl of ₆ · 6H ₂ O 33% by weight aqueous solution) was 200pp
m was added to obtain an aqueous curable resin composition. The obtained aqueous curable resin composition was applied to an aluminum
The coating was applied to a thickness of 5 μm and left at room temperature for one month to form a cured coating.

Comparative Example 4 (Preparation of Aqueous Resin Composition) To 100 g (in terms of solid content) of the acrylic emulsion obtained in Comparative Example 2, 10 g of butyl cellosolve was added as a film-forming aid, and an aqueous chloroplatinic acid solution (H ₂ PtCl ₆・
Aqueous resin composition was obtained by adding 100 ppm of a 33% by weight aqueous solution of 6H ₂ O). The obtained aqueous resin composition was applied to an aluminum base material so as to have a thickness of about 15 μm, and was thermally cured at 100 ° C. for 30 minutes to form a coating film.

Comparative Example 5 (Preparation of Aqueous Resin Composition) Except for using the silicone acrylic emulsion obtained in Comparative Example 3 in place of the acrylic emulsion obtained in Comparative Example 2, the others were the same as in Comparative Example 4. An aqueous resin composition was prepared in the same manner as described above, and a coating film was formed.

Comparative Example 6 (Preparation of Solvent-Based Resin Composition) 43 parts by weight of the organopolysiloxane compound represented by the above average composition formula (c) and 70 parts by weight of xylol were charged into a reaction vessel, and this was stirred under stirring. Heated to 100 ° C.
In addition, 3-methyl-3-butenyl methacrylate 28.
A mixture of 5 parts by weight, 26.2 parts by weight of n-butyl methacrylate, 2.3 parts by weight of methacrylic acid and 1 part by weight of dimethyl-2,2'-azoisobutyrate was dropped at a constant speed over 3 hours, and then dropped. After the completion, the temperature was kept for 3 hours. When this was cooled, a transparent resin solution was obtained. The resulting resin solution of chloroplatinic acid isopropanol solution (H ₂ PtCl ₆ · 6H ₂
O 2 weight% isopropanol solution) 1 part by weight,
Using this, a coating film was formed in the same manner as in Comparative Example 4.

Evaluation The following tests were carried out on the coating films obtained in Examples 7 to 13 and Comparative Examples 4 to 6. Table 1 shows the results. (Xylol rubbing test) 1 impregnated with xylene
Rub the coating film 50 times with absorbent cotton of size cm × 1cm,
The appearance of the subsequent coating film was visually evaluated.

(Gel Fraction) The residual ratio (% by weight) of the coating film when the coating film was boiled in acetone for 3 hours was examined. (Water resistance) The coating film was immersed in warm water at 40 ° C. for one day, and the change in the coating film appearance was visually evaluated. The evaluation criteria are as follows. A: No abnormality. ：: slight whitening. Δ: whitening. X: Dissolution.

(Weather Resistance) The coating film was irradiated for 2,000 hours using a sunshine weatherometer. Thereafter, the 60 ° specular gloss of the coating film was measured, and the gloss retention after irradiation (%) with respect to the gloss at the start of the test was determined.

(Heat resistance) Thermogravimetric method (heating rate 10 ° C. /
), The thermal decomposition onset temperature and the residual coating weight ratio (%) at 600 ° C were measured.

(Mechanical strength) A dynamic viscoelasticity test of the coating film (test condition: 11 Hz, heating rate 2 ° C./min) was carried out.
The temperature variance of nδ was determined. The peak temperature was taken as the dynamic Tg of the coating film from the obtained temperature dispersion, and the crosslinking density was calculated from the elastic modulus of the rubber region.

[0079]

[Table 1]

[0080]

The aqueous curable resin composition according to the present invention comprises:
Since it contains the above-mentioned silicone acrylic emulsion and a hydrosilylation reaction catalyst, it is possible to form a film having the same water resistance, weather resistance, heat resistance and mechanical strength as a film made of a solvent-based curable resin composition. it can.

Since the silicone acrylic emulsion according to the present invention contains the above-mentioned acrylic resin, organopolysiloxane compound and anionic surfactant, it has the same water resistance as that of a film made of a solvent-based curable resin composition. It is useful as a material for an aqueous curable resin composition for forming a film having heat resistance, weather resistance, heat resistance and mechanical strength.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yoshitaka Okude 19-17 Ikedanakacho, Neyagawa-shi, Osaka Nippon Paint Co., Ltd. (72) Inventor Mitsuhiro Takada 1-10 Hitomi Matsuidacho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Industry Co., Ltd.

Claims (5)

[Claims] 1. An aqueous medium, an acrylic resin having at least two alkenyl groups in one molecule, an organopolysiloxane represented by the following average composition formula (1) and having at least two hydrosilyl groups in one molecule: An aqueous curable resin composition comprising: a silicone acrylic emulsion containing a compound and an anionic surfactant; and a hydrosilylation reaction catalyst. Embedded image (Wherein, R ¹ is an alkyl group having 1 to 6 carbon atoms, a phenyl group or a phenethyl group, R ² is a hydrogen or methyl group, X is a 3-acryloyloxypropyl group or 3
A methacryloyloxypropyl group,
a, b and c are respectively 0 ≦ a ≦ 10, 0 ≦ b ≦ 30 when R ² is hydrogen, and 2 ≦ b ≦ 3 when R ² is a methyl group.
0 and an integer in the range of 0 ≦ c ≦ 3. ) 2. The acrylic resin comprises allyl acrylate, allyl methacrylate, 3-methyl-3-acrylate.
The aqueous curable resin according to claim 1, which is a copolymer prepared using at least one alkenyl group-containing acrylic monomer selected from the group consisting of butenyl and 3-methyl-3-butenyl methacrylate. Composition. 3. The aqueous curable resin composition according to claim 1, wherein the anionic surfactant has an alkenyl group. 4. The silicone acrylic emulsion according to claim 1,
3. The composition according to claim 1, further comprising 30 to 99 parts by weight of said acrylic resin, 1 to 70 parts by weight of said organopolysiloxane compound and 0.1 to 15 parts by weight of said anionic surfactant. Or the aqueous curable resin composition according to 3. 5. An aqueous medium, an acrylic resin having at least two alkenyl groups in one molecule, and an organo resin represented by the following average composition formula (1) and having at least two hydrosilyl groups in one molecule: A silicone acrylic emulsion comprising a polysiloxane compound and an anionic surfactant. Embedded image (Wherein, R ¹ is an alkyl group having 1 to 6 carbon atoms, a phenyl group or a phenethyl group, R ² is a hydrogen or methyl group, X is a 3-acryloyloxypropyl group or 3
A methacryloyloxypropyl group,
a, b and c are respectively 0 ≦ a ≦ 10, 0 ≦ b ≦ 30 when R ² is hydrogen, and 2 ≦ b ≦ 3 when R ² is a methyl group.
0 and an integer in the range of 0 ≦ c ≦ 3. )