JP2016008298A - Coating modifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paint composition that makes it possible to form a smooth coating with excellent adhesion on a base material and also has heat dryability.SOLUTION: A coating modifier comprises a (meth) acrylic polymer (A). The (meth) acrylic polymer (A) is emulsion in aqueous solvent with its weight average molecular weight of 5000-50000.

Description

The present invention relates to a coating film modifier.

The coating composition is widely used in various fields such as automobiles, railway vehicles, ships, aircraft, electrical equipment, building structures, construction equipment, etc., to form a coating film on the base material to protect the base material. Yes. In such an industrially used coating composition, the handleability and workability of the coating composition are high, and the appearance and adhesiveness of the coating film obtained using the coating composition are good. It is also important. The coating composition generally contains a polymer, a pigment, a solvent, and the like, and further includes a coating film modifier. The coating film modifier is used to appropriately improve various functions required for the coating composition.

A coating composition for improving various functions such as vibration damping (for example, see Patent Documents 1 to 3) and a leveling agent for smoothing a coating film are disclosed (for example, Non-Patent Documents 1 and 2). reference.).

Japanese Patent Publication No.57-57757 JP-A-10-316888 JP 2011-57829 A

“Color Material Association Journal”, Color Material Association, Vol. 68, No. 4, p.234-244 (1995) “Role and action of surface conditioner”, [online], Enomoto Kasei Co., Ltd., [Search on March 31, 2014], Internet <URL: http://www.kusumoto.co.jp/pdf/tecnews /hyomen-yakuwari.pdf>

As described above, various attempts have been made to obtain a coating film having various functions improved with respect to the resin composition used for coating. However, for any of the above, it is possible to suppress the rising (edge) part of the coating film in the coating process such as heating and drying, and the smoothness of the coating film surface can be sufficiently improved. Is hard to say. In coating compositions used industrially, it is an important factor that a smooth coating film with improved surface smoothness can be formed, the smoothness is further improved, and it can be used more suitably in various industrial applications. There is a need for a coating composition that can form a coating film.

This invention is made | formed in view of the said present condition, and it aims at providing the coating composition which can form the coating film which is smooth and excellent in adhesiveness on a base material, and is excellent also in heat drying property.

The present inventor has made various studies on the blending of a coating composition that can be used for coating applications and can obtain a smooth coating film, and variously studied on polymers to be blended in the coating composition. And by adding the (meth) acrylic polymer (A) which is an emulsion in an aqueous solvent and has a weight average molecular weight of 5000 to 50000 as a coating film modifier to the main component of the coating composition, In the coating process such as heating and drying the coating composition applied on top, the effect of obtaining a smooth coating film in which the end (edge) portion of the coating film was not raised and the shape was maintained was confirmed. The appearance of the coating film thus obtained is remarkably excellent, and the adhesion with a substrate such as a steel plate is also improved. Moreover, the coating composition to which the coating film modifier is added also improves the heat drying property. Furthermore, the present inventor has intensively studied and, together with the (meth) acrylic polymer (A), (meta) as a main ingredient component having a weight average molecular weight larger than the weight average molecular weight of the (meth) acrylic polymer (A). ) By using a coating composition containing an acrylic polymer (B) and an inorganic filler, it has been found that the effect of the (meth) acrylic polymer (A) can be exhibited more remarkably. Thus, the present invention has been achieved.

That is, the present invention is a coating film modifier containing a (meth) acrylic polymer (A), wherein the (meth) acrylic polymer (A) is an emulsion in an aqueous solvent and has a weight average molecular weight. It is a coating-film modifier which is 5000-50000.
The present invention is also a coating composition comprising the coating film modifier of the present invention, wherein the coating composition further comprises a (meth) acrylic polymer (B) and an inorganic filler, The acrylic polymer (B) is also a coating composition having a weight average molecular weight larger than that of the (meth) acrylic polymer (A).
Furthermore, this invention is also a coating film obtained using the coating composition of this invention.
And this invention is a method of manufacturing a coating film, Comprising: The said manufacturing method has a weight average molecular weight larger than the weight average molecular weight of (meth) acrylic-type polymer (A) and this polymer (A) (meta). ) Including a step of coating the acrylic polymer (B) with an inorganic filler, and the (meth) acrylic polymer (A) is an emulsion in an aqueous solvent and has a weight average molecular weight of 5,000 to 50,000. It is also a method for producing a coating film.

The present invention is described in detail below.
In addition, the form which combined two or more each preferable form of this invention described below is also a preferable form of this invention.

<1. Coating film modifier>
The coating film modifier of the present invention includes a (meth) acrylic polymer (A) that is an emulsion in an aqueous solvent, and the (meth) acrylic polymer (A) has a weight average molecular weight of 5,000 to 50,000. is there. The weight average molecular weight is preferably 7000 or more, more preferably 9000 or more, and still more preferably 11000 or more. Further, the weight average molecular weight is preferably 40000 or less, more preferably 30000 or less, and more preferably 20000 or less, because the edge deformation of the coating film is more sufficiently suppressed during coating film formation and a smoother coating film is obtained. More preferred is 17000 or less.
The said weight average molecular weight can be measured on the conditions mentioned later by GPC (gel permeation chromatography).

The coating film modifier of the present invention is added to the main component (a (meth) acrylic polymer (B) described later), and is used to improve various performances such as smoothness in the coating film. It is not used to form a coating film composed only of the coating film modifier of the present invention.
1 type may be sufficient as the said (meth) acrylic-type polymer (A), and 2 or more types may be sufficient as it. Moreover, as long as the modifier for coating films of this invention contains the said (meth) acrylic-type polymer (A), components, such as an emulsion which does not correspond to a (meth) acrylic-type polymer (A), an inorganic filler mentioned later, are included. May be included.

The (meth) acrylic polymer (A) is formed by a polymer obtained from a monomer component containing a (meth) acrylic monomer.
In the present specification, a (meth) acrylic monomer is a monomer having an acryloyl group or a methacryloyl group, or a group in which a hydrogen atom in these groups is replaced with another atom or atomic group, or Means a derivative of such a monomer. The (meth) acrylic monomer has an acid group (—COOH group) or a group in which the —COOH group has become an ester or a salt.

The (meth) acrylic polymer (A) preferably has an SP value of 9.5 or more. Thereby, the adhesive strength of a coating film can be made excellent. Moreover, the edge part deformation | transformation of a coating film can be suppressed more fully at the time of coating-film formation, and a smoother coating film can be obtained. Conventionally, when a resin composition (also referred to as a wet coating film) applied on a substrate is heated and dried to form a coating film, the edge (edge) portion of the wet coating film has a resin composition. Since the surface area with respect to the amount of material is large, it is easy to dry, and when the moisture first escapes at the edge part, the resin moves from the central part of the wet coating toward the edge part, and the edge part is raised. Due to the high SP value of the acrylic polymer (A) and therefore high hydrophilicity, the (meth) acrylic polymer (A) is present on the upper side of the wet coating film together with light moisture of the specific gravity (the coating composition). (Meth) acrylic polymer (A), which is highly hydrophilic (meth) acrylic polymer (A) during the subsequent coating formation, adjusts the drying of the wet coating surface more appropriately. To be It is police. The SP value is more preferably 9.8 or more, more preferably 10 or more, and particularly preferably 10.1 or more from the viewpoint of further suppressing edge deformation of the coating film. The SP value is more preferably 14 or less, still more preferably 13 or less, still more preferably 12 or less, and particularly preferably 11 or less.
The SP value is calculated by Fedors (Polymer Eng. Sci., 14, NO. 2,147, 1974) and Tortorello et al. (J. Coat. Technol., 55, 696, 99, 1983) using the following formula (Small formula). It is preferable to obtain in the same manner as the calculation.

In the formula, δ is the SP value of the polymer. Δe ₁ is a calculated value (kcal / mol) of the evaporation energy of each monomer component constituting the polymer, and ΣΔe ₁ is a total value of the calculated values of all the monomer components constituting the polymer. ΔV _m is the calculated value (ml / mol) of the molecular volume of each monomer component constituting the polymer, and ΣΔV _m is the sum of the calculated values of all the monomer components constituting the polymer. x is the molar distribution of each monomer component constituting the polymer.
Note that normally used calculation values can be used for the evaporation energy of the monomer component and the molecular volume of the monomer component.
Thus, the SP value of the polymer can be adjusted by adjusting the type of monomer to be constituted and the composition ratio thereof.

The (meth) acrylic polymer (A) preferably has a glass transition temperature of −50 to 10 ° C. The glass transition temperature is more preferably −40 ° C. or higher, and further preferably −30 ° C. or higher. The glass transition temperature is more preferably 5 ° C. or less, and still more preferably 0 ° C. or less.
In addition, the glass transition temperature (Tg) measuring method of a polymer is a tanδ curve of -50 ° C to 100 ° C by dynamic viscoelasticity measurement using a rheometer (RSAIII, manufactured by TAinstruments, or ARES, manufactured by TAinstruments). This can be done using a method for obtaining.
The above measurement was performed by applying an emulsion on a Teflon (registered trademark) plate having a smooth surface so that the film thickness after drying was 0.2 mm, drying at 25 ° C. for 12 hours, and then drying at 150 ° C. for 30 minutes. It can be performed in a pull mode from a sample cut into a size of 25 mm in width and 5 mm in width. Alternatively, the above measurement may be carried out by applying an emulsion on a Teflon plate having a smooth surface so that the film thickness after drying is 0.5 mm, drying at 25 ° C. for 12 hours, and then drying at 150 ° C. for 30 minutes. This can be done in shear mode from a sample cut to size.
The Tg of the polymer can be measured by measuring the peak temperature of the tan δ curve. Note that the value of tan δ at the peak top of the tan δ curve (tan δ peak top value) is a high value because it shows a measure of the vibration damping performance when the coating composition of the present invention is used for vibration damping materials. The better the damping performance.

The monomer component forming the (meth) acrylic polymer (A) is 0.1 to 5% by mass of the monomer having an acid group in 100% by mass of all monomer components, and other copolymerizable components. It is preferable to contain 95 to 99.9% by mass of a monomer. By including a monomer having an acid group, aggregation of emulsion particles is suppressed by ion repulsion between acid groups, and a stabilization effect of the emulsion particles can be obtained. If the amount is less than 0.1% by mass in 100% by mass of all monomer components, there is a possibility that such a stabilizing effect of the emulsion particles cannot be obtained sufficiently. Moreover, when content of the monomer which has an acid group exceeds 5 mass% in 100 mass% of all monomer components, there exists a possibility that the water resistance of a coating film may fall. More preferably, the monomer component contains 0.3 to 4% by mass of an acid group-containing monomer and 96 to 99.7% by mass of other copolymerizable monomers. Preferably, the acid group-containing monomer is contained in an amount of 0.5 to 2% by mass, and other copolymerizable monomers are contained in an amount of 98 to 99.5% by mass.
The monomer having an acid group may be an acid anhydride. In other words, the acid group may be a product obtained by dehydration condensation of two carboxyl groups.

The monomer having an acid group is preferably an unsaturated carboxylic acid monomer. The unsaturated carboxylic acid monomer may be a compound having an unsaturated bond and a carboxyl group in the molecule, but preferably contains an ethylenically unsaturated carboxylic acid monomer.
Examples of the ethylenically unsaturated carboxylic acid monomer include (meth) acrylic acid, crotonic acid, itaconic acid, fumaric acid, maleic acid, monomethyl fumarate, monoethyl fumarate, monomethyl maleate, monoethyl maleate, etc. 1 type or 2 types or more, such as these unsaturated carboxylic acids or its derivative (s). Among these, a (meth) acrylic acid monomer is preferable.
The (meth) acrylic acid monomer has an acryloyl group or a methacryloyl group, or a group in which a hydrogen atom in these groups is replaced with another atom or atomic group, and an acid group, It means a monomer in which the acid group is not an ester or salt. Moreover, (meth) acrylic acid means acrylic acid and / or methacrylic acid.
That is, the (meth) acrylic polymer (A) is an acrylic acid emulsion formed from an acrylic acid polymer obtained from a monomer component containing a (meth) acrylic acid monomer. preferable.

Examples of the (meth) acrylic acid monomer include (meth) acrylic acid, crotonic acid, citraconic acid, itaconic acid, maleic acid, maleic anhydride, fumaric acid, and the like. More than seeds can be used.

The monomer component used as the raw material of the (meth) acrylic polymer (A) contains (meth) acrylic acid monomer in an amount of 50% by mass or more with respect to 100% by mass of the monomer having an acid group. It is preferable to contain 70 mass% or more, and it is more preferable to contain 100 mass%.

Examples of (meth) acrylic monomers other than (meth) acrylic monomers include, for example, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, isopropyl acrylate, isopropyl methacrylate, butyl Acrylate, butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, pentyl acrylate, pentyl methacrylate, isoamyl acrylate, isoamyl methacrylate, hexyl acrylate, hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, octyl acrylate, octyl methacrylate , Iso Cutyl acrylate, isooctyl methacrylate, nonyl acrylate, nonyl methacrylate, isononyl acrylate, isononyl methacrylate, decyl acrylate, decyl methacrylate, dodecyl acrylate, dodecyl methacrylate, tridecyl acrylate, tridecyl methacrylate, hexadecyl acrylate, hexadecyl methacrylate, octadecyl Acrylate, octadecyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, vinyl formate, vinyl acetate, vinyl propionate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, diallyl Phthalate, tri Rilcyanurate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,4-butanediol diacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, In addition to diethylene glycol diacrylate, diethylene glycol dimethacrylate, allyl acrylate, allyl methacrylate, and the like, salts of the above-described (meth) acrylic acid monomers are exemplified. Among them, the polarity (SP value) of the (meth) acrylic polymer (A) can be preferably improved, and the edge deformation of the coating film can be more sufficiently suppressed during coating film formation, and a smoother coating film can be obtained. Therefore, for example, ethyl acrylate and hydroxyethyl (meth) acrylate are preferable. One or more (meth) acrylic monomers other than the (meth) acrylic acid monomer can be used.

The salt is preferably a metal salt, ammonium salt, organic amine salt or the like. Examples of the metal atom forming the metal salt include monovalent metal atoms such as alkali metal atoms such as lithium, sodium and potassium; divalent metal atoms such as alkaline earth metal atoms such as calcium and magnesium; aluminum, Trivalent metal atoms such as iron are suitable, and the organic amine salt is preferably an alkanolamine salt such as an ethanolamine salt, diethanolamine salt, or triethanolamine salt, or a triethylamine salt.

Other copolymerizable monomers other than the (meth) acrylic monomer contained in the monomer component forming the (meth) acrylic polymer (A) include copolymerizable ethylenically unsaturated monomers. A monomer is preferable, and includes an unsaturated monomer having a nitrogen atom, an unsaturated compound having an aromatic ring, and other monomers copolymerizable with a (meth) acrylic acid monomer. Of these, unsaturated compounds having a nitrogen atom are preferred.

Examples of the unsaturated monomer having a nitrogen atom include acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, diacetone acrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-methoxymethyl (meth) acrylamide, N- Examples include methoxyethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, Ni-butoxymethyl (meth) acrylamide, etc. Among them, polarity (SP value) of (meth) acrylic polymer (A) Acrylonitrile and acrylamide are preferable, for example. These can be used alone or in combination of two or more.

Examples of the unsaturated compound having an aromatic ring include divinylbenzene, styrene, α-methylstyrene, vinyltoluene, and ethylvinylbenzene. Styrene is preferred.

That is, it is also a preferred embodiment of the present invention that the (meth) acrylic polymer (A) is a styrene (meth) acrylic polymer obtained from a monomer component containing styrene. .

In summary, the (meth) acrylic polymer (A) can suitably improve its polarity (SP value), more sufficiently suppress the deformation of the edge of the coating during coating formation, and provide a smoother coating. From the viewpoint of obtaining a film, it is preferable to include a structural unit derived from at least one monomer selected from the group consisting of hydroxyethyl (meth) acrylate, acrylonitrile, ethyl acrylate, and acrylamide.

The monomer component that is a raw material of the (meth) acrylic polymer (A) is at least one monomer selected from the group consisting of ethyl acrylate, hydroxyethyl (meth) acrylate, acrylonitrile, and acrylamide. It is more preferable to use together. In this case, the monomer component contains at least one monomer selected from the group consisting of hydroxyethyl (meth) acrylate, acrylonitrile, and acrylamide with respect to 100% by mass of the total monomer components. It is preferably contained in an amount of at least mass%, more preferably at least 2 mass%, still more preferably at least 3 mass%. The monomer component is 20% by mass of at least one monomer selected from the group consisting of hydroxyethyl (meth) acrylate, acrylonitrile, and acrylamide with respect to 100% by mass of the total monomer components. % Or less, preferably 19% by mass or less, more preferably 18% by mass or less. When the content of the monomer is within the above range, the effects of the present invention can be suitably obtained.

The (meth) acrylic polymer (A) preferably has an average particle size of 50 to 500 nm.
If particles (emulsion particles) of (meth) acrylic polymer (A) having an average particle diameter in this range are used, the coating composition may be excellent in basic performance such as heat drying property and coating property. it can. The lower limit is more preferably 100 nm, and still more preferably 150 nm. The upper limit is more preferably 450 nm, still more preferably 400 nm. When the average particle diameter of the emulsion particles is within such a range, these functions and effects are more effectively exhibited.
The average particle size (volume average particle size) can be determined by, for example, diluting the emulsion with distilled water and thoroughly stirring and mixing, then collecting about 10 ml in a glass cell, and measuring the particle size distribution by a dynamic light scattering method (Particle Sizing). It can be determined by measuring with "NICOMP Model 380" manufactured by Systems.

The solid content of the (meth) acrylic polymer (A) is preferably 35 to 80% by mass with respect to 100% by mass of the coating film modifier of the present invention. The content is more preferably 40 to 75% by mass, and still more preferably 45 to 70% by mass. The solid content (nonvolatile content) of the (meth) acrylic polymer (A) means a portion other than the solvent in the emulsion.
The solid content of the (meth) acrylic polymer (A) was measured by weighing about 1 g of the emulsion in the obtained aqueous solvent, drying it at 110 ° C. for 1 hour with a hot air dryer, and weighing the remaining amount of the dry matter as a nonvolatile content. The ratio to the mass before drying can be obtained.

The pH of the (meth) acrylic polymer (A) is preferably 2 to 10, for example, more preferably 3 to 9, and still more preferably 7 to 8.
In this specification, pH can be measured with a pH meter. It is preferable to measure the value at 25 ° C. using a pH meter (“F-23” manufactured by Horiba, Ltd.).

The viscosity of the (meth) acrylic polymer (A) is, for example, preferably 1 to 10000 mPa · s, more preferably 5 to 2000 mPa · s, and still more preferably 5 to 1000 mPa · s.
The viscosity can be measured using a B-type rotational viscometer under the conditions of 25 ° C. and 20 rpm.

When the coating film modifier of the present invention contains the above (meth) acrylic polymer (A) and other emulsions, the other emulsions include urethane resins, SBR resins, epoxy resins, vinyl acetate resins, Examples thereof include vinyl chloride resins, vinyl chloride-ethylene resins, vinylidene chloride resins, styrene-butadiene resins, acrylonitrile-butadiene resins, and the like, and one or more of these can be used.
When the coating film modifier of the present invention contains other emulsions, the mass ratio of the (meth) acrylic polymer (A) to the other emulsion (the (meth) acrylic polymer (A) / others The emulsion is preferably 100-50 / 0-50.

As a method for producing an emulsion contained in the coating film modifier of the present invention, the monomer component is polymerized by an emulsion polymerization method in the presence of an emulsifier. The polymerization can be carried out by appropriately adding a monomer component, a polymerization initiator and an emulsifier to the medium. Moreover, it is preferable to use a polymerization chain transfer agent or the like for molecular weight adjustment.

The emulsifier may be any of anionic, cationic, nonionic, and amphoteric, and one or more of these may be used. Among them, anionic or nonionic is preferable. The emulsifier may be a low molecular surfactant or a high molecular surfactant. The emulsifier may be a reactive emulsifier. Since the reactive emulsifier binds to the polymer forming the emulsion, any reactive emulsifier can exhibit high resilience stability.
By using such an emulsifier, the (meth) acrylic polymer (A) can be preferably produced.

The emulsifier is preferably a nonionic surfactant and / or a sulfate ester type anionic surfactant.
That is, the (meth) acrylic polymer (A) is obtained by using a nonionic surfactant and / or a sulfate ester type anionic surfactant as an emulsifier when the monomer component is emulsion-polymerized. Preferably there is.

Examples of the nonionic surfactant include nonionic surfactants such as polyoxyethyleneoxypropylene copolymer; allyloxymethylalkoxyethylhydroxypolyoxyethylene (for example, “ADEKA rear soap ER-20” manufactured by ADEKA) And nonionic surfactants having reactivity such as polyoxyalkylene alkenyl ether (for example, “Latemul PD-420”, “Latemul PD-430” manufactured by Kao Corporation) and the like.
Examples of the sulfate type anionic surfactant include polyoxyalkylene alkyl ether sulfate, polyoxyalkylene alkenyl ether sulfate, polyoxyalkylene alkylphenyl ether sulfate (for example, “Lebenol WZ” manufactured by Kao Corporation) ), Polyoxyalkylene (mono, di, tri) styryl phenyl ether sulfate, polyoxyalkylene (mono, di, tri) benzyl phenyl ether sulfate, polyoxyalkyl ether sulfate, polyoxyethylene carboxylic acid ester Examples thereof include sulfate ester salts. The salt is preferably a sodium salt, for example.
1 type may be used for the said emulsifier and 2 or more types may be used for it.

It is preferable that the usage-amount of the said emulsifier is 0.1-10 mass parts with respect to 100 mass parts of monomer components used as the raw material of the said (meth) acrylic-type polymer (A), and is 1-6 mass parts. More preferably.

The polymerization initiator may be any substance that decomposes by heat and generates radical molecules, but a water-soluble initiator is preferably used. For example, persulfates such as potassium persulfate, ammonium persulfate, and sodium persulfate; water-soluble such as 2,2'-azobis (2-amidinopropane) dihydrochloride, 4,4'-azobis (4-cyanopentanoic acid) Thermal decomposition initiators such as hydrogen peroxide; hydrogen peroxide and ascorbic acid, t-butyl hydroperoxide and Rongalite, potassium persulfate and metal salts, redox polymerization of ammonium persulfate and sodium bisulfite, etc. Examples thereof include potassium persulfate. As said polymerization initiator, these 1 type (s) or 2 or more types can be used.
The amount of the polymerization initiator used may be appropriately set according to the type of the polymerization initiator and the like. For example, it is 0.05 to 2 parts by mass with respect to 100 parts by mass of all monomer components. Is more preferable, and 0.1 to 1.0 part by mass is more preferable.

In order to promote emulsion polymerization, the polymerization initiator can be used in combination with a reducing agent as necessary. Examples of the reducing agent include reducing organic compounds such as ascorbic acid, tartaric acid, citric acid, and glucose; for example, reducing inorganic compounds such as sodium thiosulfate, sodium sulfite, sodium bisulfite, and sodium metabisulfite. These 1 type (s) or 2 or more types can be used.
When using the said reducing agent, as the usage-amount of this reducing agent, it is preferable that it is 0.05-1 mass part with respect to 100 mass parts of all the monomer components, for example.

Examples of the polymerization chain transfer agent include alkyl mercaptans such as hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan; carbon tetrachloride, tetrabromide Halogenated hydrocarbons such as carbon and ethylene bromide; mercaptoacetic acid alkyl esters such as mercaptoacetic acid 2-ethylhexyl ester, mercaptopropionic acid 2-ethylhexyl ester, mercaptopropionic acid tridecyl ester; mercaptoacetic acid methoxybutyl ester, mercaptopropion Mercaptocarboxylic acid alkoxyalkyl esters such as acid methoxybutyl ester; carboxylic acid mercaptoalkyl esters such as octameric acid 2-mercaptoethyl ester; α-methylstyrene dimer, terpinolene, α-terpinene, γ-terpinene, dipentene, anisole, allyl alcohol, and the like. Among these, hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexa Alkyl mercaptans such as decyl mercaptan and n-tetradecyl mercaptan are preferred. These may be used alone or in combination of two or more. As the usage-amount of a polymerization chain transfer agent, it is 2.0 mass parts or less normally with respect to 100 mass parts of all the monomer components, for example, Preferably it is 1.0 mass part or less. Preferably the minimum of the usage-amount of a polymerization chain transfer agent is 0.1 mass part.

The emulsion polymerization may be performed in the presence of a chelating agent such as sodium ethylenediaminetetraacetate, a dispersing agent such as sodium polyacrylate, an inorganic salt, or the like, if necessary. Moreover, as addition methods, such as a monomer component and a polymerization initiator, methods, such as a batch addition method, a continuous addition method, a multistage addition method, are applicable, for example. Moreover, you may combine these addition methods suitably.

Regarding the emulsion polymerization conditions in the above production method, the polymerization temperature is preferably, for example, 0 to 100 ° C, more preferably 40 to 95 ° C, and still more preferably 60 to 90 ° C. Moreover, it is suitable for polymerization time to be 1 to 15 hours, for example, More preferably, it is 2 to 8 hours.
Moreover, as addition methods, such as a monomer component and a polymerization initiator, methods, such as a batch addition method, a continuous addition method, a multistage addition method, are applicable, for example. Moreover, you may combine these addition methods suitably.

In the method for producing an emulsion such as the (meth) acrylic polymer (A) contained in the coating film modifier of the present invention, the emulsion is neutralized with a neutralizing agent after the emulsion is produced by emulsion polymerization. It is preferable. As a result, the emulsion is stabilized. Examples of the neutralizing agent include triethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, N- (β-aminoethyl) ethanolamine, diglycolamine, monoethanolamine, 2-hydroxyethylpiperidine, benzylamine, 2- (2-aminoethylamino) ethanol, 2- (2-aminoethylamino) isopropanol, 1,6-hexamethylenediamine; aqueous ammonia; sodium hydroxide and the like can be used. These may be used alone or in combination of two or more.

<2. Coating composition>
This invention is a coating composition containing the modifier for coating films of this invention, Comprising: The said coating composition further contains a (meth) acrylic-type polymer (B) and an inorganic filler, The said (meth) acrylic. The weight average molecular weight of the polymer (B) is also a coating composition larger than the weight average molecular weight of the (meth) acrylic polymer (A). The coating composition of the present invention has a synergistic effect of exerting the above-mentioned effect more remarkably by selection of a polymer as a main ingredient of the composition by selecting a coating film modifier to be added to the emulsion. An extremely excellent effect can be exhibited. In addition, the preferable form of the modifier for coating films contained in the coating composition of this invention is the same as the preferable form of the modifier for coating films of this invention mentioned above.

The weight average molecular weight of the (meth) acrylic polymer (B) is larger than the weight average molecular weight of the (meth) acrylic polymer (A), preferably 10,000 or more, more preferably 50,000 or more, and still more preferably. Is larger than 80,000, particularly preferably larger than 100,000. Further, the weight average molecular weight of the (meth) acrylic polymer (B) is preferably larger than the weight average molecular weight of the (meth) acrylic polymer (A), preferably not more than 500,000, more preferably not more than 400,000. Is 300,000 or less.
The weight average molecular weights of the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) in the coating composition can be measured by GPC (gel permeation chromatography) under the conditions described later.

The two types of polymers in the coating composition are, for example, any one of various physical properties such as glass transition temperature, SP value (solubility coefficient), the type of monomer used, and the proportion of monomer used. Differentiation can be made. Moreover, even if these various physical properties are the same, when two types of peaks are observed when the molecular weight distribution is measured by GPC (gel permeation chromatography), two types of polymers corresponding to the respective peaks are observed. It can be recognized that there is. In addition, when the ratio of the Z-average molecular weight to the weight average molecular weight (Mz / Mw) is confirmed to be 2.4 or more, it can be recognized that there are two types of polymers corresponding to the respective peaks.
The Z-average molecular weight can be measured by GPC (gel permeation chromatography).

The SP value of the (meth) acrylic polymer (B) is preferably smaller than the SP value of the (meth) acrylic polymer (A), and the effect based on the (meth) acrylic polymer (A) is remarkable. From the standpoint of achieving this, it is more preferably 0.1 or more, even more preferably 0.2 or less, even more preferably 0.3 or less, and particularly preferably 0.32 or less. Further, the SP value of the (meth) acrylic polymer (B) is more preferably 3 or less, still more preferably 2 or less, particularly preferably the SP value of the (meth) acrylic polymer (A). 1 or less.
The SP value can be obtained by the formula used by Fedors (Polymer Eng. Sci., 14, NO. 2,147, 1974) and Tortorello et al. (J. Coat. Technol., 55, 696, 99, 1983).

The glass transition temperature of the (meth) acrylic polymer (B) is preferably higher than the glass transition temperature of the (meth) acrylic polymer (A), more preferably 10 ° C or higher, and 20 ° C or higher. More preferably, it is more preferably 30 ° C. or more, more preferably 35 ° C. or more. From the viewpoint of remarkably improving the heat drying property of the coating composition and the adhesive strength of the coating film, 46 ° C. Most preferably, it is larger.
The glass transition temperature is a peak temperature of a tan δ curve measured by the above-described dynamic viscoelasticity measuring apparatus.

The (meth) acrylic polymer (B) can be formed from the same monomer component as the (meth) acrylic polymer (A), but the polarity of the (meth) acrylic polymer (B) (SP Value) or the glass transition temperature is increased from the viewpoint of increasing the polarity (SP value) of the (meth) acrylic polymer (A). It is preferable not to use acrylonitrile, ethyl acrylate or acrylamide as a monomer component. Further, from the viewpoint of reducing the polarity of the (meth) acrylic polymer (B) or increasing the glass transition temperature, a monomer having no functional group such as methyl methacrylate, 2-ethylhexyl acrylate, butyl acrylate, etc. Is preferably used as the main component. The use of a monomer having no functional group as a main component means that 50% by mass or more of a monomer having no functional group is used in 100% by mass of the monomer component, preferably 60% by mass. More preferably 70% by mass or more, still more preferably 80% by mass or more, still more preferably 90% by mass or more, and particularly preferably 95% by mass or more. That is. Other configurations of the (meth) acrylic polymer (B) are the same as those of the (meth) acrylic polymer (A).

In addition, the said (meth) acrylic-type polymer (B) may be formed with one type of polymer, and may be formed with two or more types of polymers. Moreover, the said (meth) acrylic-type polymer (B) can be prepared by the method similar to the said (meth) acrylic-type polymer (A), The preferable method is also the same.

In the coating composition of the present invention, the content of the (meth) acrylic polymer (A) is preferably 5 parts by mass or more with respect to 100 parts by mass of the (meth) acrylic polymer (B). The amount is more preferably 7 parts by mass or more, further preferably 9 parts by mass or more, and particularly preferably 10 parts by mass or more. There exists a possibility that the effect of this invention cannot fully be exhibited as content of this (meth) acrylic-type polymer (A) is less than 5 mass parts. Further, the content of the (meth) acrylic polymer (A) is preferably 50 parts by mass or less, more preferably 40 parts by mass or less, still more preferably 30 parts by mass or less, and 20 It is particularly preferable that the amount is not more than part by mass. When content of this (meth) acrylic-type polymer (A) exceeds 50 mass parts, there exists a possibility that the effect corresponding to content may not be acquired.

In the coating composition of the present invention, the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) are (1) synthesized separately by polymerization and then mixed with the obtained emulsion. A form that is a mixture obtained by (blending), (2) a form that is a mixture obtained by producing (for example, multi-stage polymerization, etc.) containing two types of polymers in a series of production steps. . From the viewpoint of obtaining the effects of the present invention more suitably, the form (1) is preferred. In addition, in order to obtain what contains two types of polymers in a series of manufacturing processes, it can obtain by setting manufacturing conditions, such as monomer dropping conditions, suitably.

In the form of (1) above, at least one of the emulsions obtained by separately polymerizing may be obtained by producing (for example, multistage polymerization) containing two types of polymers. . For example, one or each of the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) may constitute an emulsion particle having a core part and a shell part. In this case, the glass transition temperature, SP value (solubility coefficient), weight average molecular weight, etc. of the emulsion particles having a core part and a shell part refer to those of the emulsion particles as a whole.

The thing of the form of said (2) can also demonstrate the effect of this invention. When the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) are combined to form an emulsion particle having a core part and a shell part, the core part and the shell part are completely It may be of a homogeneous structure that is compatible and indistinguishable, or may be a core-shell composite structure or a microdomain structure in which they are not completely compatible but formed inhomogeneously. In addition, (meth) acrylic-type polymer (A) and (meth) acrylic-type polymer (A) and (meth) acrylic-type polymer (B) are the emulsion which has a core part and a shell part integrally. Any one of the (meth) acrylic polymers (B) may constitute the emulsion core and the other may constitute the shell.
Among the emulsions having the core part and the shell part described above, the emulsion is preferably in the form of particles, and in order to produce a stable emulsion, a core / shell composite structure is preferred.
In the core / shell composite structure, the surface of the core part is preferably covered with the shell part. In this case, it is preferable that the surface of the core part is completely covered with the shell part, but it may not be completely covered. For example, the core part may be covered in a mesh shape or in some places. The part may be exposed.
The polymer having a core-shell composite structure is, for example, any one of various physical properties such as glass transition temperature, SP value (solubility coefficient), the type of monomer used, and the proportion of monomer used. What is necessary is just to be different between a core part and a shell part.

The emulsion having the core part and the shell part is preferably obtained by using a usual emulsion polymerization method. Specifically, in the presence of an emulsifier, the monomer component is emulsion-polymerized in an aqueous medium to form a core portion, and then the monomer component is further emulsion-polymerized into an emulsion containing the core portion to form a shell portion. It is preferable to obtain by the multistage polymerization to form.

Examples of the aqueous medium include water, one or more mixed solvents that can be mixed with water, and a mixed solvent in which water is a main component in such a solvent. . Among these, it is preferable to use water.

The coating composition of the present invention contains an inorganic filler in addition to the coating film modifier of the present invention. Examples of the inorganic filler include inorganic substances such as calcium carbonate, kaolin, silica, talc, barium sulfate, alumina, titanium oxide, iron oxide, zinc oxide, glass talk, magnesium carbonate, aluminum hydroxide, talc, diatomaceous earth, and clay. Fillers; scale-like inorganic fillers such as glass flakes and mica; and fibrous inorganic fillers such as metal oxide whiskers and glass fibers, among which calcium carbonate, titanium oxide and zinc oxide are preferred. These 1 type (s) or 2 or more types can be used.

In the coating composition of the present invention, the content of the inorganic filler is preferably 50 parts by mass or more and 100 parts by mass or more with respect to 100 parts by mass of the (meth) acrylic polymer (B). More preferably, it is more preferably 150 parts by mass or more, and particularly preferably 180 parts by mass or more. Further, the content of the inorganic filler is preferably 300 parts by mass or less, more preferably 270 parts by mass or less, further preferably 250 parts by mass or less, and 230 parts by mass or less. Particularly preferred.

The coating composition of the present invention may further contain other components. Examples of other components include pigments, thickeners, foaming agents, solvents, fillers, gelling agents, dispersants, antifoaming agents, crosslinking agents, plasticizers, stabilizers, wetting agents, preservatives, and antifoaming agents. Agents; anti-aging agents; antifungal agents; ultraviolet absorbers; antistatic agents and the like, and one or more of these may be used.

Examples of the pigment include organic or inorganic colorants such as carbon black, petal, hansa yellow, benzine yellow, phthalocyanine blue, and quinacridone red, and a metal phosphate, metal molybdate, borate and the like. Examples include rust pigments. Among these, inorganic pigments are preferable.

The pigment preferably has a particle size of 1 to 150 μm. Such a small particle size has poor stability and tends to aggregate, but when used in combination with the coating composition of the present invention, aggregation is suppressed and the coating composition has excellent mechanical stability. It can be. Therefore, it can be said that a form using such a particle size as a pigment is also a suitable form of the coating composition of the present invention.

Examples of the thickener include polyvinyl alcohol, cellulose derivatives, polycarboxylic acid resins, and the like. As a compounding quantity of a thickener, it is preferable to set it as 0.01-2 mass parts by solid content with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention, and 0.1-1. It is more preferable to set it as 5 mass parts, and it is still more preferable to set it as 0.5-1.2 mass parts.
In the present specification, the solid content of the polymer emulsion in the coating composition of the present invention refers to (meth) acrylic polymer (A), (meth) acrylic polymer (B), and other polymer emulsions. It means the total amount of solids.

As the foaming agent, for example, a low-boiling hydrocarbon encapsulated heated expansion capsule, an organic foaming agent, an inorganic foaming agent, and the like are suitable, and one or more of these can be used. Examples of the heated expansion capsule include Matsumoto Microsphere F-30, F-50 (manufactured by Matsumoto Yushi Co., Ltd.); EXPANSELL WU642, WU551, WU461, DU551, DU401 (manufactured by Nippon Expandcel). Examples of the organic foaming agent include azodicarbonamide, azobisisobutyronitrile, N, N-dinitrosopentamethylenetetramine, p-toluenesulfonylhydrazine, p-oxybis (benzenesulfohydrazide), and the like. Examples of the foaming agent include sodium bicarbonate, ammonium carbonate, silicon hydride and the like. As a compounding quantity of a foaming agent, it is preferable to set it as 0.5-5 mass parts with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention, and it is more preferable to set it as 1-3 mass parts. preferable.

Examples of the solvent include ethylene glycol, butyl cellosolve, butyl carbitol, butyl carbitol acetate, and the like. What is necessary is just to set suitably as a compounding quantity of a solvent so that solid content concentration of a coating composition may become the range mentioned above.

Examples of the dispersant include inorganic dispersants such as sodium hexametaphosphate and sodium tripolyphosphate, and organic dispersants such as polycarboxylic acid-based dispersants. As content of this dispersing agent, it is preferable to set it as 0.1-5 mass parts by solid content with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention, and 0.5-3 mass More preferably, it is a part.

Examples of the antifoaming agent include silicon-based antifoaming agents. As content of this antifoamer, it is preferable to set it as 0.1-5 mass parts by solid content with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention, 0.3-2 It is more preferable to set it as a mass part.

As said crosslinking agent, a water-system crosslinking agent is mentioned, for example. Examples of the water-based crosslinking agent include oxazoline compounds such as Epocross WS-500, WS-700, K-2010, 2020, and 2030 (all trade names, manufactured by Nippon Shokubai Co., Ltd.); Adeka Resin EMN-26-60, EM- Epoxy compounds such as 101-50 (Brand name, manufactured by ADEKA); Melamine compounds such as Cymel C-325 (Brand name, manufactured by Mitsui Cytec); Block isocyanate compounds; AZO-50 (Brand name, 50% by mass) Zinc oxide compounds such as zinc oxide aqueous dispersion (manufactured by Nippon Shokubai Co., Ltd.) are preferred. As a compounding quantity of a water-system crosslinking agent, it is preferable to set it as 0.01-20 mass parts by solid content, for example with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention, More preferably, it is 0. 0.1 to 15 parts by mass, more preferably 0.2 to 10 parts by mass. The water-based cross-linking agent may be added to the resin, or may be added simultaneously when other components are blended as the coating composition of the present invention.

As other components of the aqueous crosslinking agent, a polyvalent metal compound may be further used.
The form of the polyvalent metal compound may be, for example, a powder, an aqueous dispersion, an emulsion dispersion, or the like. Especially, since the dispersibility in a coating composition improves, it is preferable to use with the form of an aqueous dispersion or an emulsion dispersion, More preferably, it is used with the form of an emulsion dispersion. Moreover, it is preferable that the usage-amount of a polyvalent metal compound shall be 0.05-5.0 mass parts with respect to 100 mass parts of solid content of the polymer emulsion in the coating composition of this invention. More preferably, it is 0.05-3.5 mass parts.

Examples of the plasticizer include phthalates such as dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dihexyl phthalate, dioctyl phthalate, diisononyl phthalate, di-2-ethylhexyl phthalate, dibenzyl phthalate, diisodecyl phthalate, ditridecyl phthalate, and diundecyl phthalate. Examples include acid esters, and among them, diisononyl phthalate is preferable.

When the coating composition of this invention contains a plasticizer, the coating composition of this invention contains 1-30 mass parts of plasticizers with respect to 100 mass parts of (meth) acrylic-type polymer (B) content. It is preferable that 3 to 25% by mass is included, and 5 to 20 parts by mass is still more preferable. The plasticizer may be added to the resin, or may be added simultaneously when other components are blended as the coating composition of the present invention.

In addition, the said inorganic filler and another component can be mixed with the main ingredient component, modifier, etc. in this invention using a butterfly mixer, a planetary mixer, a spiral mixer, a kneader, a dissolver etc., for example.

The solid content of the coating composition of the present invention is preferably 20% by mass or more, more preferably 30% by mass or more, still more preferably 40% by mass or more, and 50% by mass or more. Is particularly preferred. The solid content is preferably 90% by mass or less, and more preferably 80% by mass or less.
In addition, solid content concentration means components other than the solvent which a coating composition contains here. This solid content density | concentration can be measured by the method similar to the measuring method of the solid content of the (meth) acrylic-type polymer (A) mentioned above.

For example, the coating composition is applied to a substrate and dried to form a coating film. Although it does not specifically limit as a base material, For example, a steel plate is mentioned. Moreover, as a method of apply | coating a coating composition to a base material, it can apply | coat using a brush, a spatula, an air spray, an airless spray, a mortar gun, a ricin gun etc., for example.

<3. Coating Film>
The present invention is also a coating film obtained using the coating composition of the present invention. If the coating film of this invention is obtained from the coating composition containing the (meth) acrylic-type polymer (A), (meth) acrylic-type polymer (B), and inorganic filler which concern on this invention, Good. The preferable form of the coating composition used for obtaining the coating film of the present invention is the same as the preferable form of the above-described coating composition of the present invention.

The coating film of the present invention preferably has a film thickness after drying of 1.5 mm or more, more preferably 2 mm or more, and particularly preferably 3 mm or more. Conventionally, the thicker the coating film, the larger the problem that the thickness of the coating film becomes non-uniform. However, the present invention can solve the problem. The thickness of the coating film is preferably 10 mm or less, more preferably 8 mm or less, and still more preferably 5 mm. In view of exhibiting sufficient vibration damping properties and the point of forming a good coating film, the above thickness range is preferable.
The film thickness of the coating film can be measured with calipers.

The base material for forming the coating film of the present invention is not particularly limited as long as the coating film can be formed, and may be any metal material such as a steel plate, plastic material and the like. Especially, forming a coating film on the surface of a steel plate is one of the preferable usage forms of the coating film of this invention.

The coating film of the present invention can be obtained, for example, by applying the coating composition of the present invention using a brush, spatula, air spray, airless spray, mortar gun, ricin gun or the like.

The coating film of the present invention is preferably obtained by heating and drying the coating composition of the present invention. ADVANTAGE OF THE INVENTION According to this invention, the subject that it becomes easy to produce the swelling of an edge part in the heat drying process of a coating composition can fully be eliminated.
In heat drying, the coating film formed by applying the coating composition of the present invention on a substrate is preferably 40 ° C or higher, more preferably 60 ° C or higher, and 90 ° C or higher. More preferably, it is more preferably 100 ° C. or higher. It is preferable to simultaneously perform drying of the coating film and volatilization of the neutralizing agent in the coating film by using such a heating and drying temperature. Moreover, the upper limit of the heat drying is preferably 200 ° C, more preferably 150 ° C, and further preferably 130 ° C.
Moreover, it is preferable that the time which makes a coating film the said temperature is 1 to 300 minutes. More preferably, it is 2 to 250 minutes, and particularly preferably 10 to 150 minutes.

The coating film of the present invention can be easily formed and has a smooth surface and excellent appearance. Moreover, since the surface of a coating film is smooth, it is thought that the coating film of this invention is excellent also in vibration damping property and impact resistance.

<4. Manufacturing method of coating film>
The present invention is a method for producing a coating film, wherein the production method has a (meth) acrylic polymer (A) and a weight average molecular weight larger than the weight average molecular weight of the polymer (A). Including a step of coating the acrylic polymer (B) and the inorganic filler, and the (meth) acrylic polymer (A) is an emulsion in an aqueous solvent and has a weight average molecular weight of 5,000 to 50,000. It is also a method for producing a coating film.
The preferable form of the coating film in the manufacturing method of the coating film of this invention is the same as the preferable form of the coating film of this invention mentioned above.

The step of coating the (meth) acrylic polymer (A), the (meth) acrylic polymer (B), and the inorganic filler comprises the steps of (meth) acrylic polymer (A), ( The (meth) acrylic polymer (B) and the inorganic filler may be mixed to obtain a mixture, and then the mixture may be coated, and the (meth) acrylic polymer (A) and the The (meth) acrylic polymer (B) may be applied separately.

The above (meth) acrylic polymer (A), the above (meth) acrylic polymer (B), and an inorganic filler are mixed to obtain a mixture, and then the mixture is made into a coating film, thereby simplifying the process. The effect of the present invention can be suitably obtained in the coating step. Here, mixing the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) means (1) mixing and synthesizing the emulsions obtained separately. Blending), and (2) manufacturing a product containing (meth) acrylic polymer (A) and (meth) acrylic polymer (B) in a series of manufacturing steps (for example, multistage polymerization). Can be mentioned. From the viewpoint of obtaining the effects of the present invention more suitably, the form (1) is preferred.

Further, when the (meth) acrylic polymer (A) and the (meth) acrylic polymer (B) are separately applied, a composition containing the (meth) acrylic polymer (B) is usually applied on a substrate. What is necessary is just to apply | coat the composition containing this (meth) acrylic-type polymer (A) next. Here, after applying the (meth) acrylic polymer (B) and the (meth) acrylic polymer (A), a coating step may be performed, or the (meth) acrylic polymer (B) may be used. You may perform a coating-film formation process both after apply | coating and after apply | coating this (meth) acrylic-type polymer (A). Thus, by applying twice, the drying of the coating film can be very appropriately adjusted by the (meth) acrylic polymer (A) unevenly distributed on the coating film surface, and the smoothness of the coating film surface can be adjusted. It can be considered to be outstanding.

Moreover, it is preferable to perform the said coating-film formation process, for example by heat-drying a coating composition. The preferable conditions for heat drying are the same as those described above for the coating film of the present invention.

The coating film modifier of the present invention has the above-described configuration, and can form a coating film having a smooth and excellent adhesive property on a substrate, and a coating composition having an excellent heat drying property can be obtained. .

It is sectional drawing of the coating material apply | coated on the base material and the base material. It is a top view of the coating material apply | coated on the base material and the base material. It is a figure which shows a mode that the test plate has been arrange | positioned in a heating furnace. It is a figure which shows the center part and peripheral part (frame part) of a coating film.

The present invention will be described in more detail with reference to the following examples. However, the present invention is not limited to these examples. Unless otherwise specified, “part” means “part by mass” and “%” means “% by mass”.

In the following production examples and examples, various physical properties and the like were evaluated as follows.

<Weight average molecular weight>
It measured by GPC (gel permeation chromatography) on the following measurement conditions.
Measuring instrument: HLC-8120GPC (trade name, manufactured by Tosoh Corporation)
Molecular weight column: TSK-GEL GMHXL-L and TSK-GELG5000HXL (both manufactured by Tosoh Corporation) are connected in series. Eluent: Tetrahydrofuran (THF)
Standard material for calibration curve: Polystyrene (manufactured by Tosoh Corporation) PStQuick Kit-M
Flow rate 1.0ml / min
Measurement method: The molecular weight was measured by dissolving a measurement object in THF so that the solid content was about 0.2% by mass, and filtering it with a filter (0.45 μm).

<Solubility parameter (SP value)>
The SP value of each polymer forming each emulsion is calculated by the following formula (Fedors (Polymer Eng. Sci., 14, NO. 2,147, 1974) and Tortorello et al. (J. Coat. Technol., 55, 696, 99, 1983): It was calculated in the same manner as that calculated using the Small formula.

In the formula, δ is the SP value of the polymer. Δe ₁ is a calculated value (kcal / mol) of the evaporation energy of each monomer component constituting the polymer, and ΣΔe ₁ is a total value of the calculated values of all the monomer components constituting the polymer. ΔV _m is the calculated value (ml / mol) of the molecular volume of each monomer component constituting the polymer, and ΣΔV _m is the sum of the calculated values of all the monomer components constituting the polymer. x is the molar distribution of each monomer component constituting the polymer.
For the evaporation energy of the monomer component and the molecular volume of the monomer component, commonly used calculated values were used.

<Glass transition temperature (Tg)>
The glass transition temperature (Tg) of the polymer is measured by a dynamic viscoelasticity measurement using a rheometer (RSAIII, manufactured by TAinstruments, or ARES, manufactured by TAinstruments) to obtain a tan δ curve of −50 ° C. to 100 ° C. The method was used.
In the case of the emulsions obtained in Production Examples 1 to 3, 18 and 19 described later, the above measurement was performed by applying the emulsion on a Teflon plate having a smooth surface so that the film thickness after drying was 0.2 mm, and 25 ° C. The sample was dried for 12 hours at 150 ° C. for 30 minutes, and the sample was cut in a size of 25 mm length × 5 mm width in a tensile mode (measurement conditions: 3 ° C./min, frequency 1 Hz, strain 0.1%). . In the case of the emulsions obtained in Production Examples 4 to 17 and 20, which will be described later, the emulsion was applied on a Teflon plate having a smooth surface so that the film thickness after drying was 0.5 mm. After drying for 12 hours, the sample was dried at 150 ° C. for 30 minutes and cut into a 25 mm diameter sample in shear mode (measurement conditions: 3 ° C./min, frequency 1 Hz, strain 0.1%).
In addition, since the emulsion with low Tg has adhesiveness, a test body cannot be produced as a film and it is difficult to measure in a tensile mode. Therefore, the emulsion having a low Tg was measured in the shear mode as described above.
The Tg of the polymer was measured by measuring the peak temperature of the tan δ curve. In addition, the value of tan δ at the peak top of the tan δ curve (tan δ peak top value) was measured.

<Nonvolatile content (N.V.)>
About 1 g of the obtained aqueous resin dispersion was weighed, and after 110 hours at 110 ° C. with a hot air drier, the remaining amount after drying was regarded as a non-volatile content, and the ratio to the mass before drying was expressed in mass%.
<PH>
The pH was measured at 25 ° C. with a pH meter (“F-23” manufactured by Horiba, Ltd.).
<Viscosity>
The viscosity was measured using a B-type rotational viscometer under the conditions of 25 ° C. and 20 rpm.

<Average particle size>
The average particle size (volume average particle size) is obtained by diluting the emulsion with distilled water and mixing thoroughly with stirring, and then collecting about 10 ml in a glass cell, and measuring the particle size distribution by a dynamic light scattering method (Particle Sizing Systems) ("NICOMP Model 380" manufactured by Nikon Corporation)).

<Production example of polymer emulsion>
(Production Example 1)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 67.1 parts of methyl methacrylate (MMA), 19.9 parts of butyl acrylate (BA), 12.0 parts of 2-ethylhexyl acrylate (2EHA), 1.0 part of acrylic acid (AA), n- 0.2 parts of dodecyl mercaptan (n-DM), lebenol WZ (trade name, manufactured by Kao, sodium polyoxyethylene nonylphenyl ether sulfate, the same applies hereinafter) 10.0 parts previously prepared in a 20% aqueous solution and deionized water 32 A monomer emulsion consisting of 0.0 part was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the resulting reaction solution to room temperature, 0.7 part of 25% aqueous ammonia and 13 parts of diisononyl phthalate (DINP) (content 13% with respect to nonvolatile content) were added, and the weight average molecular weight (Mw) 150,000, Non-volatile content 55.0%, DINP content 13% with respect to non-volatile content, glass transition temperature 31 ° C., tan δ peak top value 2.1, SP value 9.85, pH 7.8, viscosity 350 mPa · s, average particle size 330 nm Emulsion B1 was obtained.

(Production Example 2)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 55.7 parts of methyl methacrylate (MMA), 33.2 parts of butyl acrylate (BA), 12.0 parts of 2-ethylhexyl acrylate (2EHA), 1.0 part of acrylic acid (AA), n- A monomer emulsion consisting of 0.2 parts of dodecyl mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction solution to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 120,000, nonvolatile content 55.0%, glass transition temperature 31 ° C., tan δ peak top value 1. 9, an emulsion B2 having an SP value of 9.85, a pH of 7.9, a viscosity of 180 mPa · s, and an average particle size of 320 nm was obtained.

(Production Example 3)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 67.1 parts of methyl methacrylate (MMA), 19.9 parts of butyl acrylate (BA), 12.0 parts of 2-ethylhexyl acrylate (2EHA), 1.0 part of acrylic acid (AA), n- A monomer emulsion comprising 5.0 parts of dodecyl mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the resulting reaction liquid to room temperature, 0.7 part of 25% aqueous ammonia and 13 parts of DINP (content 13% with respect to nonvolatile content) were added, weight average molecular weight (Mw) 17000, nonvolatile content 54.8. %, Non-volatile content of DINP 13%, glass transition temperature 31 ° C., tan δ peak top value 2.1, SP value 9.85, pH 7.7, viscosity 100 mPa · s, average particle size 330 nm Emulsion B3 .

(Production Example 4)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 39.4 parts of methyl methacrylate (MMA), 59.6 parts of butyl acrylate (BA), 1.0 part of acrylic acid (AA), 5.0 parts of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ and 32.0 parts of deionized water, which was previously adjusted to a 20% aqueous solution, was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 15000, nonvolatile content 55.0%, glass transition temperature −11 ° C., tan δ peak top value 2 An emulsion A1 having an .53, an SP value of 9.88, a pH of 7.6, a viscosity of 110 mPa · s, and an average particle diameter of 350 nm was obtained.

(Production Example 5)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 7.1 parts of methyl methacrylate (MMA), 91.9 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 5.0 parts of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ and 32.0 parts of deionized water, which was previously adjusted to a 20% aqueous solution, was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 15000, nonvolatile content 54.9%, glass transition temperature −11 ° C., tan δ peak top value 2 And Emulsion A2 having an SP value of 10.22, a pH of 7.8, a viscosity of 150 mPa · s, and an average particle size of 280 nm were obtained.

(Production Example 6)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 7.1 parts of methyl methacrylate (MMA), 91.9 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 1.0 part of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ and 32.0 parts of deionized water, which was previously adjusted to a 20% aqueous solution, was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction solution to room temperature, 0.7 part of 25% aqueous ammonia was added, weight average molecular weight (Mw) 45000, nonvolatile content 55.0%, glass transition temperature −11 ° C., tan δ peak top value 2 And an emulsion A3 having an SP value of 10.22, a pH of 7.9, a viscosity of 210 mPa · s, and an average particle size of 280 nm were obtained.

(Production Example 7)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 0.1 part of methyl methacrylate (MMA), 88.9 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 10.0 parts of hydroxyethyl methacrylate (HEMA), n-dodecyl are added to the dropping funnel. A monomer emulsion consisting of 5.0 parts of mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% aqueous ammonia was added, weight average molecular weight (Mw) 15000, nonvolatile content 54.8%, glass transition temperature −11 ° C., tan δ peak top value 2 An emulsion A4 having an SP of 10.55, an SP value of 10.55, a pH of 7.8, a viscosity of 400 mPa · s, and an average particle diameter of 270 nm was obtained.

(Production Example 8)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 24.4 parts of methyl methacrylate (MMA), 59.6 parts of butyl acrylate (BA), 1.0 part of acrylic acid (AA), 15.0 parts of hydroxyethyl methacrylate (HEMA), n-dodecyl are added to the dropping funnel. A monomer emulsion consisting of 5.0 parts of mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 15000, nonvolatile content 54.8%, glass transition temperature -12 ° C., tan δ peak top value 2 Emulsion A5 having an SP of 10.89, a pH of 7.8, a viscosity of 800 mPa · s, and an average particle size of 270 nm was obtained.

(Production Example 9)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 9.0 parts of methyl methacrylate (MMA), 75.0 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 15.0 parts of hydroxyethyl acrylate (HEA), n-dodecyl are added to the dropping funnel. A monomer emulsion consisting of 5.0 parts of mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 9000, nonvolatile content 54.7%, glass transition temperature -12 ° C., tan δ peak top value 2 An emulsion A6 having an SP of 10.98, an SP value of 10.82, a pH of 7.7, a viscosity of 500 mPa · s, and an average particle diameter of 250 nm was obtained.

(Production Example 10)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 2.4 parts of methyl methacrylate (MMA), 91.6 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 5.0 parts of acrylonitrile (AN), n-dodecyl mercaptan ( n-DM) 5.0 parts, a monomer emulsion consisting of 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% aqueous ammonia was added, weight average molecular weight (Mw) 13000, non-volatile content 54.9%, glass transition temperature −10 ° C., tan δ peak top value 2 , SP value 10.2, pH 7.6, viscosity 140 mPa · s, and average particle diameter 310 nm were obtained as emulsion A7.

(Production Example 11)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 0.8 parts of methyl methacrylate (MMA), 93.2 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 5.0 parts of acrylamide, n-dodecyl mercaptan (n-DM) ) 5.0 parts, a monomer emulsion consisting of 10.0 parts of Rebenol WZ and 32.0 parts of deionized water previously adjusted to a 20% aqueous solution was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 7000, nonvolatile content 54.8%, glass transition temperature -12 ° C., tan δ peak top value 2 An emulsion A8 having an SP of 10.2, an SP value of 10.2, a pH of 7.9, a viscosity of 750 mPa · s, and an average particle size of 260 nm was obtained.

(Production Example 12)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 12.6 parts of methyl methacrylate (MMA), 86.4 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 5.0 parts of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ and 32.0 parts of deionized water, which was previously adjusted to a 20% aqueous solution, was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 15000, nonvolatile content 54.9%, glass transition temperature −6 ° C., tan δ peak top value 2 An emulsion A9 having an SP of 10.63, an SP value of 10.22, a pH of 7.5, a viscosity of 180 mPa · s, and an average particle diameter of 280 nm was obtained.

(Production Example 13)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 3.7 parts of methyl methacrylate (MMA), 95.3 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 5.0 parts of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ and 32.0 parts of deionized water, which was previously adjusted to a 20% aqueous solution, was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 15000, nonvolatile content 54.9%, glass transition temperature -14 ° C., tan δ peak top value 2 And Emulsion A10 having an SP value of 10.22, a pH of 7.7, a viscosity of 140 mPa · s, and an average particle size of 280 nm were obtained.

(Production Example 14)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 8.6 parts of styrene (St), 80.4 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 10.0 parts of hydroxyethyl acrylate (HEA), n-dodecyl mercaptan A monomer emulsion consisting of 5.0 parts of (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 13000, non-volatile content 54.8%, glass transition temperature −11 ° C., tan δ peak top value 2 , 59, SP value 10.47, pH 7.2, viscosity 130 mPa · s, and average particle diameter 250 nm were obtained as emulsion A11.

(Production Example 15)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 0.1 part of methyl methacrylate (MMA), 88.9 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 10.0 parts of hydroxyethyl methacrylate (HEMA), n-dodecyl are added to the dropping funnel. A monomer emulsion consisting of 0.4 parts of mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 75000, nonvolatile content 55.1%, glass transition temperature −11 ° C., tan δ peak top value 2 An emulsion A12 having an SP value of 10.55, a pH of 7.9, a viscosity of 600 mPa · s, and an average particle size of 280 nm was obtained.

(Production Example 16)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 0.1 part of methyl methacrylate (MMA), 88.9 parts of ethyl acrylate (EA), 1.0 part of acrylic acid (AA), 10.0 parts of hydroxyethyl methacrylate (HEMA), n-dodecyl are added to the dropping funnel. A monomer emulsion consisting of 50.0 parts of mercaptan (n-DM), 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. Although the obtained reaction liquid was cooled to room temperature and 0.7 part of 25% aqueous ammonia was added to obtain emulsion A13, a polymer emulsion could not be obtained.

(Production Example 17)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 50.7 parts of methyl methacrylate (MMA), 48.3 parts of 2-ethylhexyl acrylate (2EHA), 1.0 part of acrylic acid (AA), 0.2 parts of n-dodecyl mercaptan (n-DM) are added to the dropping funnel. Part, a monomer emulsion consisting of 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 320,000, nonvolatile content 55.0%, glass transition temperature 10 ° C., tan δ peak top value 2. 3. An emulsion B4 having an SP value of 9.58, a pH of 7.7, a viscosity of 150 mPa · s, and an average particle size of 290 nm was obtained.

(Production Example 18)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 70.3 parts of methyl methacrylate (MMA), 28.7 parts of 2-ethylhexyl acrylate (2EHA), 1.0 part of acrylic acid (AA), 0.2 parts of n-dodecyl mercaptan (n-DM) are added to the dropping funnel. Part, a monomer emulsion consisting of 10.0 parts of Lebenol WZ previously adjusted to a 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% aqueous ammonia was added, weight average molecular weight (Mw) 250,000, nonvolatile content 55.0%, glass transition temperature 50 ° C., tan δ peak top value 1. Emulsion B5 having an SP value of 9.74, a pH of 8.1, a viscosity of 80 mPa · s, and an average particle size of 330 nm was obtained.

(Production Example 19)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. On the other hand, 49.5 parts of methyl methacrylate (MMA), 0.5 part of acrylic acid (AA), 0.1 part of n-dodecyl mercaptan (n-DM) were added to the above dropping funnel. A monomer emulsion consisting of 0 parts and 16.0 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 90 minutes while maintaining the inside of the reaction system at 80 ° C. (first stage addition). The same temperature was maintained for 60 minutes after the completion of dropping. Meanwhile, 20.3 parts of methyl methacrylate (MMA), 28.7 parts of 2-ethylhexyl acrylate (2EHA), 0.5 part of acrylic acid (AA), 0.1 part of n-dodecyl mercaptan (n-DM) are added to the funnel. Then, a monomer emulsion consisting of 5.0 parts of Rebenol WZ and 16.0 parts of deionized water, which had been adjusted to a 20% aqueous solution in advance, was charged and used as the second drop. Then, the monomer emulsion for the second-stage dropping was continuously added dropwise over 90 minutes while maintaining the system where the first-stage dropping was reacted at 80 ° C. After completion of dropping, the second stage was maintained at the same temperature for 60 minutes. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% aqueous ammonia was added, weight average molecular weight (Mw) 280000, nonvolatile content 55.0%, glass transition temperature 35 ° C., tan δ peak top value 1. 5, a core-shell composite emulsion B6 having an SP value of 9.74, a pH of 7.9, a viscosity of 120 mPa · s, and an average particle size of 250 nm was obtained.

(Production Example 20)
37.4 parts of deionized water was charged into a polymerization vessel equipped with a stirrer, a reflux condenser, a thermometer, a nitrogen inlet tube and a dropping funnel. Thereafter, the internal temperature was raised to 75 ° C. while stirring under a nitrogen gas stream. Meanwhile, 40.1 parts of styrene (St), 58.9 parts of butyl acrylate (BA), 1.0 part of acrylic acid (AA), 5.0 parts of n-dodecyl mercaptan (n-DM), A monomer emulsion consisting of 10.0 parts of Lebenol WZ adjusted to 20% aqueous solution and 32.0 parts of deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 1 part of the monomer emulsion and 4 parts of 5% potassium persulfate aqueous solution were added to initiate initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 180 minutes while maintaining the inside of the reaction system at 80 ° C. The same temperature was maintained for 60 minutes after the completion of dropping. After cooling the obtained reaction liquid to room temperature, 0.7 part of 25% ammonia water was added, weight average molecular weight (Mw) 11000, nonvolatile content 54.7%, glass transition temperature −10 ° C., tan δ peak top value 2 Emulsion A14 having an .64, SP value of 9.4, pH of 7.4, a viscosity of 90 mPa · s, and an average particle size of 300 nm was obtained.

<Examples 1-18, Comparative Examples 1-4>
Example 1
Emulsion B1 obtained in Production Example 1 and emulsion A1 obtained in Production Example 4 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain Resin Composition A.

(Example 2)
Emulsion B1 obtained in Production Example 1 and emulsion A2 obtained in Production Example 5 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition B.

(Example 3)
Emulsion B1 obtained in Production Example 1 and emulsion A2 obtained in Production Example 5 were mixed at a mixing ratio (mass ratio) of 7/3 to obtain a resin composition C.

Example 4
Emulsion B1 obtained in Production Example 1 and emulsion A3 obtained in Production Example 6 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition D.

(Example 5)
Emulsion B1 obtained in Production Example 1 and emulsion A4 obtained in Production Example 7 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition E.

(Example 6)
Emulsion B1 obtained in Production Example 1 and emulsion A5 obtained in Production Example 8 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition F.

(Example 7)
Emulsion B1 obtained in Production Example 1 and emulsion A6 obtained in Production Example 9 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition G.

(Example 8)
Emulsion B1 obtained in Production Example 1 and emulsion A7 obtained in Production Example 10 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition H.

Example 9
Emulsion B1 obtained in Production Example 1 and emulsion A8 obtained in Production Example 11 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition I.

(Example 10)
Emulsion B1 obtained in Production Example 1 and emulsion A9 obtained in Production Example 12 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition J.

(Example 11)
Emulsion B1 obtained in Production Example 1 and emulsion A10 obtained in Production Example 13 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition K.

(Example 12)
Emulsion B1 obtained in Production Example 1 and emulsion A11 obtained in Production Example 14 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition L.

(Example 13)
Emulsion B2 obtained in Production Example 2 and emulsion A1 obtained in Production Example 4 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition M.

(Example 14)
Emulsion B2 obtained in Production Example 2 and emulsion A2 obtained in Production Example 5 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition N.

(Example 15)
Emulsion B4 obtained in Production Example 17 and emulsion A4 obtained in Production Example 7 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition O.

(Example 16)
Emulsion B5 obtained in Production Example 18 and Emulsion A4 obtained in Production Example 7 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition P.

(Example 17)
Emulsion B6 obtained in Production Example 19 and emulsion A4 obtained in Production Example 7 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition Q.

(Example 18)
The emulsion B1 obtained in Production Example 1 and the emulsion A14 obtained in Production Example 20 were mixed at a 9/1 mixing ratio (mass ratio) to obtain a resin composition R.

(Comparative Example 1)
Emulsion B1 obtained in Production Example 1 was designated as resin composition S.

(Comparative Example 2)
Emulsion B1 obtained in Production Example 1 and emulsion A12 obtained in Production Example 15 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition T.

(Comparative Example 3)
The emulsion B1 obtained in Production Example 1 and the emulsion A13 obtained in Production Example 16 were mixed at a mixing ratio (mass ratio) of 9/1 to obtain a resin composition U. Couldn't get because it became impossible.

(Comparative Example 4)
Emulsion B3 obtained in Production Example 3 was designated as Resin Composition V.

<Preparation of coating composition>
The resin compositions A to R of Examples 1 to 18 and the resin compositions S, T, and V of Comparative Examples 1, 2, and 4 were blended as follows, and a damping material coating film was prepared as a damping material blend. The coating contents, heat drying properties, smoothness of the coating film surface, and adhesive strength were evaluated for comprehensive evaluation. The results are shown in Table 1.
Resin compositions A to T, V (nonvolatile content 55%) 100 parts Calcium carbonate (NN # 200 ^{* 1} ) 100 parts Dispersant (Aquaric DL-40S ^{* 2} ) 1 part Thickener (Acryset WR-650 ^{* 3} ) 0.5 part · Antifoaming agent (Nopco 8034L ^{* 4} ) 0.5 part · Foaming agent (F-30 ^{* 5} ) 1 part * 1: Filler * 2 manufactured by Nitto Flour Industries : Nippon Shokubai Co., Ltd. polycarboxylic acid type dispersant (active ingredient 44%)
* 3: Nippon Shokubai Co., Ltd. Alkali-soluble acrylic thickener (active ingredient 30%)
* 4: Defoaming agent manufactured by San Nopco Co., Ltd. (main component: hydrophobic silicone + mineral oil)
* 5: Matsumoto Yushi Seiyaku Co., Ltd. foaming agent

In Table 1, “ΔSP” represents the difference obtained by subtracting the SP value of emulsion B (main agent) from the SP value of emulsion A (surface modifier), and “δTg” represents the emulsion from the Tg of emulsion B (main agent). It represents the difference obtained by subtracting the Tg of A (surface modifier).

Evaluation methods for various properties are shown below.

(Evaluation of coating film content, heat drying property, and smoothness of coating film surface)
A test plate made of the base material shown in FIGS. 1 and 2 and a paint applied on the base material under the following conditions is dried by heating in a heating furnace as shown in FIG. / The film thickness and weight of the edge portion were measured and evaluated according to the following evaluation criteria.

(1) A wet coating film (thickness 5 mm × width 30 cm × length 30 cm) was applied on a Teflon substrate, and then heated and dried at 150 ° C. for 30 minutes.
(2) After heating, the coating film was cooled to room temperature and peeled off from the Teflon substrate.
(3) The weight (unit: g) of the peeled coating film (width 30 cm × length 30 cm) was measured (the weight was defined as the dry weight).
(4) Thereafter, the coating film was heated and dried at 150 ° C. for 2 hours, and then returned to room temperature, and the weight (unit: g) was measured (the weight was defined as the absolute dry weight).
(5) Residual volatile fraction (%) = {(weight measured in (3) −weight measured in (4)) / weight measured in (3)} × 100.
(6) A central portion 20 cm × 1 cm was cut out from the coating film (width 30 cm × length 30 cm) (FIG. 4).
(7) The thickness (the thinnest part) and the weight of the cut out part were measured. The measured value was recorded in the film thickness term (mm) and the coating weight term (g) of the coating content as the film thickness at the center. Furthermore, the weight per unit area was calculated by the following formula and entered in the item.
*) Weight per unit area (g / cm ² ) = coating film weight (g) / (20 cm × 1 cm)
(8) The film thickness of the edge part was the highest film thickness in the peripheral part (frame part) of the coating film of (3).

(Evaluation criteria for smoothness of coating surface)
A: Thickness ratio {(thickness at the center portion / thickness at the edge portion) × 100 (%)} is 93% or more and 100% or less ○: The thickness ratio is 87% or more and less than 93% Δ: Above The film thickness ratio is 79% or more and less than 87% ▲: The film thickness ratio is 70% or more and less than 79% x: The film thickness ratio is 0% or more and less than 70% The difference between the film thickness of the central part and the film thickness of the edge part in the coating film is small, and there is an edge part deformation suppressing effect.

(Measurement method of adhesive strength of coating film)
Evaluation was performed in accordance with the quality regulation of “adhesion strength” of JIS A 6909 (architectural finishing coating material).
(Test specimen preparation method)
The obtained coating composition was applied onto a steel plate (trade name “SPCC-SD” manufactured by Nippon Test Panel Co., Ltd.) so that the coating film had a thickness of 5 mm × 30 cm × 30 cm. The applied wet coating film was dried by heating at 150 ° C. for 30 minutes and returned to room temperature. This sheet was used as a test specimen.

(Adhesive strength measurement)
A steel attachment (4 cm × 4 cm) was bonded to the sheet surface using an epoxy resin (two-component curable) adhesive. The periphery of the attachment was cut into a steel plate with a cutter. About 1 hour later, the load force when the coating film was peeled off was measured using a Kenken type single-axis hydraulic tensile tester LPT-1500. The measured numerical value was calculated by the following formula and used as the adhesive strength.
Formula: Adhesive strength (N / mm ² ) = Load force (N) / 1600 (mm ² )

(Comprehensive evaluation)
From the above evaluation results, the heat drying property, the smoothness of the coating film and the adhesiveness of the coating composition when used for coating applications were comprehensively evaluated.
A: Excellent.
○: Excellent.
Δ: Normal.
▲: Slightly inferior.
X: Inferior.

From the results of the above Examples and Comparative Examples, the coating composition obtained by using the coating film modifier having an emulsion in an aqueous solvent and having a weight average molecular weight of 5000 to 50000 is smooth and excellent in adhesiveness. It was confirmed that a coating composition which can form a coating film on a substrate and has excellent heat drying properties can be obtained.

Claims (11)

A coating film modifier comprising a (meth) acrylic polymer (A),
The (meth) acrylic polymer (A) is an emulsion in an aqueous solvent, and has a weight average molecular weight of 5,000 to 50,000. The coating modifier according to claim 1, wherein the (meth) acrylic polymer (A) has an SP value of 9.5 or more. The coating modifier according to claim 2, wherein the (meth) acrylic polymer (A) has an SP value of 10 to 14. The said (meth) acrylic-type polymer (A) has a glass transition temperature of -50-10 degreeC, The coating film modifier in any one of Claims 1-3 characterized by the above-mentioned. The (meth) acrylic polymer (A) includes a structural unit derived from at least one monomer selected from the group consisting of hydroxyethyl (meth) acrylate, acrylonitrile, ethyl acrylate, and acrylamide. The coating film modifier according to any one of claims 1 to 4. A coating composition comprising the coating film modifier according to any one of claims 1 to 5,
The coating composition further comprises a (meth) acrylic polymer (B) and an inorganic filler,
The coating composition, wherein the weight average molecular weight of the (meth) acrylic polymer (B) is larger than the weight average molecular weight of the (meth) acrylic polymer (A). In the coating composition, the content of the (meth) acrylic polymer (A) is 5 to 50 parts by mass with respect to 100 parts by mass of the (meth) acrylic polymer (B), and the inorganic filler Content is 50-300 mass parts, The coating composition of Claim 6 characterized by the above-mentioned. The coating composition according to claim 6 or 7, wherein the SP value of the (meth) acrylic polymer (B) is smaller than the SP value of the polymer (A). The coating composition according to any one of claims 6 to 8, wherein the glass transition temperature of the polymer (B) is higher than the glass transition temperature of the polymer (A). The coating film obtained using the coating composition in any one of Claims 6-9. A method for producing a coating film comprising:
The production method comprises applying a (meth) acrylic polymer (A), a (meth) acrylic polymer (B) having a weight average molecular weight larger than the weight average molecular weight of the polymer (A), and an inorganic filler. Including a film forming step,
The (meth) acrylic polymer (A) is an emulsion in an aqueous solvent, and has a weight average molecular weight of 5,000 to 50,000.

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