JP5977123B2 - Damping material - Google Patents

Description

The present invention relates to a vibration damping material. More specifically, the present invention relates to a vibration damping material used for preventing vibration and noise in various structures and maintaining silence.

The damping material is for preventing vibration and noise in various structures and maintaining silence, for example, in addition to being used under the interior floor of automobiles, railway vehicles, ships, aircraft and electrical equipment, Widely used in building structures and construction equipment. As a material used for such a damping material, conventionally, a molded product such as a plate-shaped molded body or a sheet-shaped molded body made of a material having vibration absorption performance and sound absorption performance has been used. On the other hand, when the shape of the place where vibration or sound is generated is complicated, it is difficult to apply these molded products to the place where vibration is generated. Various methods for exerting the effect have been studied. For example, asphalt sheets containing inorganic powder have been used under the floors of automobiles, etc., but since there is a need for heat-sealing, improvement in workability and the like is desired. Various compositions for damping materials and polymers to be formed have been studied.

As described above, coating-type damping materials (paints) have been developed as substitute materials for molded products, and, for example, by coating films formed by spraying or applying by any method to the corresponding locations. Various vibration-damping paints that can obtain a vibration absorbing effect and a sound absorbing effect have been proposed. Specifically, for example, as a water-based vibration-damping paint with improved coating film hardness obtained by blending a synthetic resin powder with a color developing agent such as asphalt, rubber, synthetic resin, and the like suitable for indoor use in automobiles, Anti-vibration coatings in which activated carbon is dispersed as a filler in a resin emulsion have been developed. However, even with these conventional products, the vibration damping performance is still not at a sufficiently satisfactory level, and there is a need for a technique that can further exhibit the vibration damping performance.

Conventional coating-type vibration damping materials include water-based paints (see Patent Document 1) having vibration damping properties containing a heat-expandable organic hollow filler at a predetermined ratio, water-based resin emulsions, inorganic fillers, and water retention. An aqueous coating type vibration damping material containing at least microballoon particles that start expansion under a heating temperature condition below the boiling point of water with an expansion agent while encapsulating an expansion agent that volatilizes and expands by heating with the agent ( Patent Document 2) is disclosed. In addition, an emulsion-type paint with a specified paint solid content, pigment volume concentration, and volume concentration of a large particle size pigment with a specified particle size is applied to a specified coating thickness and dried under specified conditions to apply coating type damping A method of forming a coating film of a material is disclosed (see Patent Document 3).

JP 7-145331 A JP 2010-1111746 A JP 2010-58070 A

The invention of Patent Document 1 aims to develop a paint having vibration damping properties, and the invention of Patent Document 2 suppresses peeling or deformation of the sealer and can improve blister resistance. The purpose is to provide a vibration material. Another object of the invention of Patent Document 3 is to form a coating-type damping material having a film thickness sufficient to obtain a damping action under low-temperature, short-time heating and drying conditions. The coating type damping material containing these conventional polymer components and fillers exhibits good damping properties, is excellent in the appearance of the coating film, and can easily form such a coating film. It is an issue. On the other hand, in applications where coating-type damping materials such as automobiles, railway vehicles, ships, aircraft, electrical equipment, building structures, construction equipment, etc. are used, the formed coating film is not easily damaged or peeled off. It is also an important characteristic that the coating film has excellent strength. However, as can be seen from the descriptions in Patent Documents 1 to 3, the conventional damping material composition was developed for the purpose of exhibiting excellent damping properties and good coating film appearance. At present, the strength of the coating film formed from the vibration damping composition has not been sufficiently studied.

The present invention has been made in view of the above situation, and provides a vibration damping material having a high-strength coating film that exhibits excellent vibration damping properties and sufficiently suppresses peeling of the coating film. Objective.

The present inventor has made various studies on a vibration damping material having a high-strength coating film while exhibiting excellent vibration damping properties. In the vibration damping material formed by applying vibration damping paint, when the cross-sectional void ratio of the coating film is set within a predetermined range, it has been found that the vibration damping material has both vibration damping properties and coating film strength. The present inventors have arrived at the present invention by conceiving that it can be solved on a case-by-case basis.

That is, the present invention is a vibration damping material formed by applying a vibration damping coating containing a polymer emulsion obtained by emulsion polymerization of a monomer component and a filler, and the vibration damping material has a cross section of a coating film. The vibration damping material has a porosity of 10 to 50%.
The present invention is described in detail below.
A combination of two or more preferred embodiments of the present invention described below is also a preferred embodiment of the present invention.

The vibration damping material of the present invention is formed by applying a vibration damping paint containing a polymer emulsion formed by emulsion polymerization of a monomer component and a filler, and the cross-sectional porosity of the coating film is 10 to 10. That is 50%.
Since the vibration damping material is used for applications such as automobiles, railway vehicles, ships, aircraft, electrical equipment, building structures, construction equipment, etc., it is necessary to have excellent adhesion to a base material such as a steel plate. In order to ensure sufficient adhesion of the damping material to the base material, it is important that the cross-sectional void ratio of the coating film is within a predetermined range. If the cross-sectional void ratio of the coating film is 50% or less, the coating film is not damaged and the adhesion strength is sufficiently exhibited. If the cross-sectional void ratio of the coating film is 10% or more, the coating film is not swollen and the sea surface is not peeled off, and the adhesion is not lowered. In the vibration damping material of the present invention, the cross-sectional void ratio of the coating film is 10 to 50%, so that the coating film has sufficient adhesion to the substrate, and damage and peeling of the coating film are suppressed. Excellent coating strength.
The vibration-damping material of the present invention is formed by applying a vibration-damping coating material containing a polymer emulsion and a filler, and the polymer emulsion has a cross-sectional porosity of 10 to 50%. The type of filler, the type of damping material, and the drying conditions of the damping material may be any, but the main factors affecting the cross-sectional porosity of the coating film are the number average molecular weight of the polymer contained in the damping coating, the damping The glass transition temperature of the vibration coating film, the drying temperature of the coating film, and when the vibration damping paint contains a foaming agent or pigment, the type and amount of the foaming agent contained in the vibration damping paint, the pigment in the vibration damping paint Concentration etc. are mentioned, and adjusting these to the preferable range mentioned later is the preferable method of obtaining the damping coating material whose cross-sectional porosity of a coating film is 10 to 50%.

The cross-sectional void ratio of the coating film of the vibration damping material of the present invention is preferably 12 to 45%, more preferably 12 to 40%.
The cross-sectional porosity of the coating film can be measured by the method described in Examples.

The vibration damping material of the present invention is formed by applying a vibration damping coating containing a polymer emulsion obtained by emulsion polymerization of a monomer component and a filler. The vibration-damping paint is formed by adding a component such as a filler to the emulsion composition for a vibration-damping material including a polymer emulsion.
The polymer emulsion preferably contains a polymer that forms the polymer emulsion (hereinafter also referred to as polymer (A)) and an aqueous medium.

The monomer component that is a raw material of the polymer (polymer (A)) forming the polymer emulsion in the present invention is not particularly limited as long as the effects of the present invention can be exhibited, but the unsaturated carboxylic acid single amount The body is preferably included. More preferably, it comprises an unsaturated carboxylic acid monomer and another monomer copolymerizable with the unsaturated carboxylic acid monomer. The unsaturated carboxylic acid monomer is not particularly limited as long as it is a compound having an unsaturated bond and a carboxyl group in the molecule, but preferably contains an ethylenically unsaturated carboxylic acid monomer.

The ethylenically unsaturated carboxylic acid monomer is not particularly limited. For example, (meth) acrylic acid, crotonic acid, itaconic acid, citraconic acid, fumaric acid, maleic acid, maleic anhydride, monomethyl fumarate, monoethyl One type or two or more types of unsaturated carboxylic acids such as fumarate, monomethyl maleate, monoethyl maleate, or derivatives thereof may be used. Among these, (meth) acrylic acid monomers such as (meth) acrylic acid are preferable. That is, the polymer (polymer (A)) forming the polymer emulsion is a (meth) acrylic polymer in which at least one of the monomer components is a (meth) acrylic acid monomer, 1 is one of the preferred embodiments of the present invention.

Among the above (meth) acrylic polymers, those obtained by using a monomer component containing a (meth) acrylic acid monomer are preferable. In the (meth) acrylic polymer of the present invention, at least one of the monomer components is C (R ⁴ ) ₂ = CH-COOR ⁵ or C (R ⁶ ) ₂ = C (CH ₃ ). A monomer that is a monomer represented by —COOR ⁷ (R ⁴ , R ⁵ , R ⁶ and R ⁷ are the same or different and each represents a hydrogen atom, a metal atom, an ammonium group or an organic amine group). It is preferable that it is obtained using components.
In the present specification, 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 A monomer having —COOH group, and a (meth) acrylic 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 a monomer in the form in which the —COOH group is an ester or a salt, or a derivative of such a monomer.

The monomer component used as the raw material for the (meth) acrylic polymer is 0.1 to 20% by mass of the (meth) acrylic acid monomer with respect to 100% by mass of the total monomer components, and other common components. It preferably contains 80 to 99.9% by mass of a polymerizable ethylenically unsaturated monomer. By including the (meth) acrylic acid monomer, the dispersibility of the filler such as inorganic powder is improved in the vibration-damping coating material containing the polymer emulsion, and the vibration-damping property is further improved. Moreover, it becomes easy to adjust the acid value, Tg, physical properties, etc. of a polymer by including another copolymerizable ethylenically unsaturated monomer. In the monomer component, if the (meth) acrylic acid monomer is 0.1% by mass or more and 20% by mass or less, the monomer component is stably copolymerized. In the (meth) acrylic polymer contained in the polymer emulsion, a superior vibration damping property is fully exhibited in an aqueous vibration damping material due to a synergistic effect of monomer units formed from these monomers. As well as an excellent coating film appearance.
More preferably, 0.5 to 3% by mass of the (meth) acrylic acid monomer and 100 to 97% to 99% of other copolymerizable ethylenically unsaturated monomers with respect to 100% by mass of all monomer components. .5% by mass.
Other copolymerizable ethylenically unsaturated monomers include (meth) acrylic monomers other than (meth) acrylic acid monomers, unsaturated monomers having aromatic rings, and nitrogen atoms Examples thereof include unsaturated monomers and other monomers copolymerizable with (meth) acrylic acid monomers.

Examples of (meth) acrylic monomers other than the above (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, Diethylene glycol diacrylate, diethylene glycol dimethacrylate, allyl acrylate, allyl methacrylate, and the like; these salts and esterified products can be mentioned, and it is preferable to use one or more of these.

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 preferred. As the organic amine salt, alkanolamine salts such as ethanolamine salt, diethanolamine salt, triethanolamine salt, and triethylamine salt are preferable.

As a monomer component used as the raw material of the said (meth) acrylic-type polymer, it contains 20 mass% or more of (meth) acrylic-type monomers with respect to 100 mass% of all monomer components. It is preferable. More preferably, it is 30 mass% or more.

Examples of the unsaturated monomer having an aromatic ring include divinylbenzene, styrene, α-methylstyrene, vinyltoluene, and ethylvinylbenzene. Styrene is preferred.
That is, the polymer (polymer (A)) forming the polymer emulsion is a styrene (meth) acrylic polymer obtained from a monomer component containing styrene. One.

When the polymer (polymer (A)) forming the polymer emulsion is a (meth) acrylic polymer having an aromatic ring, the unsaturated monomer having an aromatic ring with respect to 100% by mass of all monomer components. It is preferable to contain 1 to 70% by mass of the monomer. More preferably, it is 5-60 mass%, More preferably, it is 10-40 mass%. In addition, it is not necessary to use the unsaturated monomer which has an aromatic ring as a monomer component used as the raw material of the said polymer (A).

The polymer (polymer (A)) forming the polymer emulsion is also preferably obtained from a monomer component containing a polar group-containing monomer. When the polymer (A) has a polar group, the interaction between the polymers in the damping material becomes larger, and the friction between the polymers becomes larger, so that the damping performance is more fully exhibited. Become.
As a polar group which the said polar group containing monomer has, what is generally made into a polar group in an organic compound should just be mentioned, For example, a hydroxyl group and a carboxyl group are mentioned. Preferably, it is a carboxyl group.

Among the monomer components used as the raw material of the polymer (polymer (A)) forming the polymer emulsion, from the viewpoint of vibration damping and workability, a (meth) acrylic monomer, (meth) acrylic Monomers are preferred.
Thus, the polymer emulsion is preferably a (meth) acrylic polymer emulsion.

In the present invention, the polymer (polymer (A)) forming the polymer emulsion may be one kind of polymer as described above, or may be composed of two or more kinds of polymers. Further, the polymer (A) may be composed of two or more kinds of polymers, and they may be combined. In addition, when the polymer (A) is in a form having a core part and a shell part to be described later, the polymer (A) is composed of two types of polymers, and one of the two types of polymers is a core part, The other may form the shell part. For example, the unsaturated carboxylic acid monomer and the other monomer copolymerizable with the unsaturated carboxylic acid monomer are a monomer component that forms the core part of the emulsion and a monomer component that forms the shell part. It may be contained in any of these, and may be used for both of them.

Moreover, it is preferable that at least 1 type in the polymer which forms a polymer emulsion is a form of the emulsion particle which has a core part and a shell part. Thereby, the interface between polymers can be increased and effects, such as a vibration damping improvement, can be enlarged.

When the polymer emulsion in the present invention includes emulsion particles having a core part and a shell part, the core part and the shell part may be completely compatible with each other and may have a homogeneous structure in which they cannot be distinguished. A core-shell composite structure or microdomain structure that is not completely compatible but heterogeneously formed may be used, but among these structures, the characteristics of the emulsion are fully exploited to produce a stable emulsion. Therefore, a core / shell composite structure is preferable.
An emulsion having a core-shell composite structure is excellent in vibration damping properties in a wide range within a practical temperature range. Especially in the high temperature range, it exhibits excellent vibration damping performance compared to other forms of vibration damping composition. As a result, within the practical temperature range, the vibration damping performance covers a wide range from room temperature to high temperature range. Can be demonstrated.
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 (polymer (A)) forming the polymer emulsion preferably has a number average molecular weight of 10,000 to 25,000. In order to exhibit vibration damping properties, it is preferable to change the vibrational energy applied to the polymer to thermal energy due to friction, and a polymer that can move when vibration is applied to the polymer. It is necessary to be. When the polymer (A) has such a number average molecular weight, the polymer can sufficiently move when vibration is applied, and high damping properties can be exhibited. Moreover, it is preferable to use the polymer of such a number average molecular weight also from the point which makes the coating film of a damping material satisfy | fill the cross-sectional porosity mentioned above. The number average molecular weight of the polymer (A) is more preferably 15000 to 22000, and further preferably 15000 to 20000.
The number average molecular weight can be measured by GPC (gel permeation chromatography).

The polymer (polymer (A)) forming the polymer emulsion preferably has a glass transition temperature of -20 to 40 ° C. When a polymer (A) having such a glass transition temperature is used, the vibration damping performance in the practical temperature range of the vibration damping material can be effectively expressed. The glass transition temperature of the polymer (A) is more preferably -15 to 35 ° C, still more preferably -10 to 30 ° C.
The glass transition temperature (Tg) may be determined based on the knowledge already obtained, and may be controlled by the type and use ratio of the monomer component described later. It can be calculated from the following formula (1).

In the formula, Tg ′ is Tg (absolute temperature) of the polymer. W ₁ ′, W ₂ ′,... Wn ′ are mass fractions of the respective monomers with respect to the total monomer components. T ₁ , T ₂ ,... Tn are glass transition temperatures (absolute temperatures) of homopolymers (homopolymers) composed of the respective monomer components.

When at least one of the polymers (polymer (A)) forming the polymer emulsion is in the form of emulsion particles having a core part and a shell part, the glass transition temperature of the polymer in the core part is 0 to 60 ° C. Preferably there is. More preferably, it is 10-50 degreeC.
The glass transition temperature of the polymer in the shell part is preferably -30 to 30 ° C. More preferably, it is -20-20 degreeC.
Moreover, it is preferable that the difference of the glass transition temperature of the polymer of a core part and the polymer of a shell part is 5-60 degreeC. By providing a difference in the glass transition temperature in this way, for example, when applied to a damping material application, it becomes possible to express higher damping properties under a wide temperature range, which is a practical range in particular. The vibration damping property in the ˜60 ° C. region will be further improved. The difference in glass transition temperature is more preferably 5 to 50 ° C, still more preferably 5 to 40 ° C.

The average particle diameter of the emulsion particles in the polymer emulsion is preferably 80 to 450 nm.
By using emulsion particles with an average particle size in this range, the basic properties such as coating film appearance and coating properties required for vibration damping materials will be sufficient, and vibration damping will be even better. It can be. The average particle diameter of the emulsion particles is more preferably 400 nm or less, still more preferably 350 nm or less. When the average particle diameter of the emulsion particles is within such a range, the effect of the emulsion composition for vibration damping material is more effectively exhibited. The average particle size is preferably 100 nm or more.
The average particle size (volume average particle size) was determined by diluting the emulsion with distilled water, 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 Systems). It can obtain | require by measuring by "NICOMP Model 380" by a company.

The emulsion particles having the above average particle diameter preferably have a particle size distribution defined by a value obtained by dividing the standard deviation by the volume average particle diameter (standard deviation / volume average particle diameter × 100) of 40% or less. More preferably, it is 30% or less. When the particle size distribution is 40% or less, coarse particles are not included, and as a result, the emulsion composition for a vibration damping material can exhibit sufficient heat drying properties.

The emulsion composition for damping material of the present invention may contain other components as long as it contains a polymer emulsion.
When other components are included, the proportion of the other components is preferably 10% by mass or less, more preferably 5% by mass or less, with respect to the entire emulsion composition for a vibration damping material. The term “other components” as used herein means a non-volatile content (solid content) remaining in the coating film even after the emulsion composition for vibration damping material is applied and dried by heating, and does not include an aqueous medium. .
In the emulsion composition for vibration damping material of the present invention, the solid content is preferably 40 to 80% by mass, more preferably 50 to 70% by mass with respect to the whole emulsion composition for vibration damping material. .
In addition, solid content here means components other than the aqueous medium contained in the emulsion composition for vibration damping materials.

Other components other than the polymer emulsion contained in the emulsion composition for vibration damping material of the present invention include isothiazoline compounds. By including the isothiazoline-based compound, the coating film formed from the emulsion composition for a vibration damping material has excellent coating film appearance.
Examples of the isothiazoline-based compound include 1,2-benzisothiazolin-3-one (BIT), 2-methyl-4-isothiazolin-3-one (MIT), 2-octyl-4-isothiazolin-3-one (OIT), And 5-chloro-2-methyl-4-isothiazolin-3-one (C-MIT).
Further, zinc pyrithione may be used in place of the isothiazoline compound or together with the isothiazoline compound.

When the emulsion composition for vibration damping material of the present invention contains an isothiazoline compound, the content of the isothiazoline compound is in the coating film with respect to 100% by mass (solid content) of the polymer contained in the emulsion composition for vibration damping material. In view of the appearance, workability, and the like, it is preferably 0.0005 to 1.0 mass%. More preferably, it is 0.005-0.5 mass%, More preferably, it is 0.01-0.3 mass%.
When using an isothiazoline-based compound and zinc pyrithione, the total amount of these is preferably the above value.
The isothiazoline-based compound or zinc pyrithione may be used in the form of a solution by dissolving in a solvent. In that case, it is preferable to use the amount of the isothiazoline-based compound or zinc pyrithione in the solution (effective component amount) within the above range. .

Although it does not specifically limit as pH of the said emulsion composition for damping materials, It is preferable that it is 2-10, More preferably, it is 3-9.5, More preferably, it is 7-9. The pH of the polymer emulsion can be adjusted by adding ammonia water, water-soluble amines, alkali hydroxide aqueous solution and the like to the resin.
In this specification, pH can be measured with a pH meter. For example, it is preferable to measure the value at 25 ° C. using a pH meter (“F-23” manufactured by Horiba, Ltd.).

Although it does not specifically limit as a viscosity of the said emulsion composition for damping materials, It is preferable that it is 1-10000 mPa * s, More preferably, it is 5-1000 mPa * s, More preferably, it is 5-500 mPa * s.
The viscosity can be measured using a B-type rotational viscometer under the conditions of 25 ° C. and 30 min ⁻¹ .

As a method for producing the polymer emulsion, the monomer component is polymerized by an emulsion polymerization method in the presence of an emulsifier, but the form for carrying out the emulsion polymerization is not particularly limited, for example, a single amount in an aqueous medium. It can carry out by superposing | polymerizing by adding a body component, a polymerization initiator, and an emulsifier suitably. Moreover, it is preferable to use a polymerization chain transfer agent or the like for molecular weight adjustment.

When the polymer emulsion is an emulsion having a core part and a shell part, it is preferably obtained by using a usual emulsion polymerization method. Specifically, after the monomer component is emulsion-polymerized in an aqueous medium in the presence of an emulsifier and / or protective colloid to form a core part, the monomer component is further emulsion-polymerized into an emulsion containing the core part. It is preferably obtained by multistage polymerization that forms a shell portion. Thus, a form in which the polymer emulsion is an emulsion having a core part and a shell part, and the emulsion is obtained by multistage polymerization that forms a shell part after the core part is formed, is also of the present invention. One preferred form.

The aqueous medium is not particularly limited. For example, water, one or two 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. Etc. Among these, water is preferable in consideration of the safety and the influence on the environment when applying the paint containing the polymer emulsion in the present invention.

The amount of the emulsifier used is preferably 0.1 to 10% by mass with respect to 100% by mass of the total amount of compounds having a polymerizable unsaturated bond group. By being 0.1 mass% or more, mechanical stability and polymerization stability are improved. More preferably, it is 0.5-5 mass%, More preferably, it is 1-3 mass%.

As the emulsifier, one or more of anionic, cationic, nonionic and amphoteric surfactants and a polymeric surfactant can be used.
The anionic surfactant is not particularly limited, and examples thereof include polyoxyalkylene alkyl ether sulfate, polyoxyalkylene oleyl ether sulfate sodium salt, polyoxyalkylene alkylphenyl ether sulfate, alkyl diphenyl ether disulfonate, poly Oxyalkylene (mono, di, tri) styryl phenyl ether sulfate, polyoxyalkylene (mono, di, tri) benzyl phenyl ether sulfate, alkenyl succinate; sodium dodecyl sulfate, potassium dodecyl sulfate, ammonium alkyl sulfate Alkyl sulfate salts such as sodium dodecyl polyglycol ether sulfate; sodium sulforicinoate; Alkyl sulfonates such as sodium salts; alkyl sulfonates such as sodium dodecylbenzene sulfonate and alkali metal sulfates of alkali phenol hydroxyethylene; high alkyl naphthalene sulfonates; naphthalene sulfonic acid formalin condensates; sodium laurate, triethanolamine oleate, tri Fatty acid salts such as ethanolamine abietate; polyoxyalkyl ether sulfate ester; polyoxyethylene carboxylic ester sulfate salt; polyoxyethylene phenyl ether sulfate ester; succinic acid dialkyl ester sulfonate salt; polyoxyethylene alkyl aryl sulfate Examples include salts. These 1 type (s) or 2 or more types can be used.

Commercially available products suitable as the anionic surfactant include, for example, Latemul WX, Latemul 118B, Perex SS-H, Emulgen A-60, B-66, Lebenol WZ, Emar O (manufactured by Kao Corporation), New Coal 707SF , New Call 707SN, New Call 714SF, New Call 714SN, AB-26S, ABEX-2010, 2020, 2030, DSB (manufactured by Rhodia Nikka), Hightenol 18E, Hightenol NF-08 (Daiichi Kogyo Seiyaku Co., Ltd.) And the like.
In addition, surfactants corresponding to these nonionic types can also be used.

As the above anionic surfactants, reactive surfactants, reactive anionic surfactants, sulfosuccinate type reactive anionic surfactants, alkenyl succinate type reactive anionic surfactants, etc. 1 type (s) or 2 or more types can be used.
Commercially available sulfosuccinate-type reactive anionic surfactants include Latemul S-120, S-120A, S-180 and S-180A (all trade names, manufactured by Kao Corporation), Eleminol JS-2 (Products) Name, manufactured by Sanyo Kasei Kogyo Co., Ltd.), ADEKA rear soap SR-10, SR-20, SR-30 (manufactured by ADEKA) and the like.
As a commercial item of an alkenyl succinate type reactive anionic surfactant, Latemul ASK (trade name, manufactured by Kao Corporation) and the like can be mentioned.
Furthermore, (meth) acrylic acid polyoxyethylene sulfonate salt (for example, “Eleminol RS-30” manufactured by Sanyo Chemical Industries, “Antox MS-60” manufactured by Nippon Emulsifier Co., Ltd.), allyloxymethylalkyloxypolyoxy Sulfate ester (salt) having an allyl group such as sulfonate salt of ethylene (for example, “Aqualon KH-10” manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), ammonium polyoxyalkylene alkenyl ether sulfate (for example, “Latemul PD-” manufactured by Kao Corporation 104 "etc.) can also be used.

Further, as the anionic surfactant, the following surfactants and the like can be used as the reactive surfactant.
Sulfoalkyl (carbon number 1 to 4) ester salt type surfactant of aliphatic unsaturated carboxylic acid having 3 to 5 carbon atoms, for example, 2-sulfoethyl (meth) acrylate sodium salt, 3-sulfopropyl (meth) acrylate ammonium (Meth) acrylic acid sulfoalkyl ester salt type surfactants such as salts; sulfopropylmaleic acid alkylester sodium salt, sulfopropylmaleic acid polyoxyethylene alkylester ammonium salt, sulfoethylfumaric acid polyoxyethylene alkylester ammonium salt, etc. Aliphatic unsaturated dicarboxylic acid alkyl sulfoalkyl diester salt surfactants.

The nonionic surfactant is not particularly limited. For example, polyoxyethylene alkyl ether; polyoxyethylene alkyl aryl ether; sorbitan aliphatic ester; polyoxyethylene sorbitan aliphatic ester; aliphatic such as monolaurate of glycerol Monoglyceride; polyoxyethyleneoxypropylene copolymer; condensation products of ethylene oxide and aliphatic amines, amides or acids. For example, as a commercial product, Emulgen 1118S (manufactured by Kao Corporation) and the like can be mentioned. Also, allyloxymethylalkoxyethylhydroxypolyoxyethylene (for example, “ADEKA rear soap ER-20” manufactured by ADEKA), polyoxyalkylene alkenyl ether (for example, “Latemul PD-420”, “Latemul PD-” manufactured by Kao Corporation) Nonionic surfactants having reactivity such as “430” and the like can also be used. These 1 type (s) or 2 or more types can be used.

The cationic surfactant is not particularly limited, and examples thereof include dialkyldimethylammonium salts, ester-type dialkylammonium salts, amide-type dialkylammonium salts, dialkylimidazolinium salts, and the like. Can be used.

The amphoteric surfactant is not particularly limited, and examples thereof include alkyldimethylaminoacetic acid betaine, alkyldimethylamine oxide, alkylcarboxymethylhydroxyethylimidazolinium betaine, alkylamidopropylbetaine, alkylhydroxysulfobetaine, and the like. 1 type (s) or 2 or more types can be used.

The polymer surfactant is not particularly limited. For example, polyvinyl alcohol and a modified product thereof; (meth) acrylic water-soluble polymer; hydroxyethyl (meth) acrylic water-soluble polymer; hydroxypropyl (meth) acrylic Water-soluble polymers such as polyvinyl pyrrolidone, and one or more of them can be used.

In the surfactant, an ethylene oxide chain-containing anionic surfactant is preferably used. When an ethylene oxide chain-containing anionic surfactant is used, it is possible to obtain a coating film having good workability and excellent coating film appearance and vibration damping properties.
Among the above surfactants, it is preferable to use a non-nonylphenyl type surfactant from the environmental viewpoint.
The amount of the surfactant used may be appropriately set according to the type of surfactant to be used, the type of monomer component, etc., but is necessary for ensuring stability during polymerization and storage stability after polymerization. From the viewpoint of the minimum amount, for example, it is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of monomer components used to form the polymer. It is 5-5 mass parts, More preferably, it is 1-3 mass parts.

Examples of the protective colloid include polyvinyl alcohols such as partially saponified polyvinyl alcohol, fully saponified polyvinyl alcohol, and modified polyvinyl alcohol; cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose, and carboxymethyl cellulose salt; natural polysaccharides such as guar gum Etc., and one or more of these can be used. The protective colloid may be used alone or in combination with a surfactant.
The use amount of the protective colloid may be appropriately set according to use conditions and the like. For example, 5 parts by mass or less with respect to 100 parts by mass of the total amount of monomer components used to form the polymer. It is preferable that it is 3 mass parts or less.

The polymerization initiator (oxidizing agent) is not particularly limited as long as it is a 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. An agent etc. are mentioned, These 1 type (s) or 2 or more types can be used.
The amount of the polymerization initiator used is not particularly limited and may be set as appropriate according to the type of the polymerization initiator. For example, the total amount of monomer components used to form the polymer is 100 parts by mass. It is preferable that it is 0.1-2 mass parts with respect to this, More preferably, it is 0.2-1 mass part.

In order to promote emulsion polymerization, the polymerization initiator may 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, sodium thiosulfate, sodium sulfite, sodium bisulfite, sodium metabisulfite, sodium hydrogensulfite, thiourea dioxide, etc. A reducing inorganic compound etc. are mentioned, These 1 type (s) or 2 or more types can be used.
It does not specifically limit as the usage-amount of the said reducing agent, For example, it is preferable that it is 0.05-1 mass part with respect to 100 mass parts of total amounts of the monomer component used in forming a polymer.

The blending ratio of the polymerization initiator and the reducing agent (polymerization initiator / reducing agent) is a molar ratio in order to prevent decomposition of the isothiazoline-based compound that is a surface modifier when an emulsion composition for a vibration damping material is used. The ratio is preferably 1.0 to 2.0, and more preferably 1.2 to 1.9.

The polymerization chain transfer agent is not particularly limited, for example, alkyl mercaptans such as hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, n-tetradecyl mercaptan; carbon tetrachloride , Halogenated hydrocarbons such as carbon tetrabromide and ethylene bromide; mercaptocarboxylic acid alkyl esters such as mercaptoacetic acid 2-ethylhexyl ester, mercaptopropionic acid 2-ethylhexyl ester, mercaptopyropionic acid tridecyl ester; mercaptoacetic acid methoxybutyl Mercaptocarboxylic acid alkoxyalkyl ester such as ester, mercaptopropionic acid methoxybutyl ester; carboxylic acid mercaptoal such as octanoic acid 2-mercaptoethyl ester Glycol ester or, alpha-methylstyrene dimer, terpinolene, alpha-terpinene, .gamma.-terpinene, dipentene, anisole, allyl alcohol and the like. These may be used alone or in combination of two or more. Among these, alkyl mercaptans such as hexyl mercaptan, octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan, n-hexadecyl mercaptan, and n-tetradecyl mercaptan are preferably used.

As the usage-amount of the said polymerization chain transfer agent, Preferably it is 0.1-1.0 mass% with respect to 100 mass% of all monomer components, More preferably, it is 0.3-0.8 mass%. is there.

The emulsion polymerization may be performed in the presence of a chelating agent such as sodium ethylenediaminetetraacetate, a dispersant 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 not particularly limited, and is preferably 0 to 100 ° C., and more preferably 40 to 95 ° C., for example. Also, the polymerization time is not particularly limited, and is preferably 1 to 15 hours, and more preferably 5 to 10 hours, for example.
The addition method of the monomer component, the polymerization initiator, and the like is not particularly limited, and for example, a batch addition method, a continuous addition method, a multistage addition method, or the like can be applied. Moreover, you may combine these addition methods suitably.

In the manufacturing method of the said (meth) acrylic-type polymer emulsion, after manufacturing emulsion by emulsion polymerization, it is preferable to neutralize an emulsion with a neutralizing agent. As a result, the emulsion is stabilized.
Although it does not specifically limit as a neutralizer, Since the water resistance etc. of the coating film formed from the emulsion composition for damping materials which require a (meth) acrylic-type polymer emulsion improve, it volatilizes at the time of heating of a coating film It is preferable to use a volatile base. More preferably, an amine having a boiling point of 80 to 360 ° C. is used because heat drying properties are improved and vibration damping properties are improved. As such a neutralizing agent, for example, tertiary amines such as triethanolamine, 2-methylaminoethanol, dimethylethanolamine, diethylethanolamine, morpholine, and diglycolamine are preferable. More preferably, an amine having a boiling point of 130 to 280 ° C is used.
In addition, the said boiling point is a boiling point in a normal pressure.
The molecular weight of the neutralizing agent is not particularly limited, but is preferably 130 to 280 from the viewpoint of volatility.
Furthermore, it is preferable to add so that an amine may be 0.6-1.4 equivalent with respect to 1 equivalent of acid groups which the polymer contained in a polymer emulsion has. More preferably, it is 0.8-1.2 equivalent.

A vibration-damping coating material can be constituted by adding other components to the emulsion composition for vibration-damping material. Such a vibration-damping coating material, which essentially uses the emulsion composition for vibration-damping material, can exhibit excellent vibration-damping properties and can form a vibration-damping material having a coating film with excellent coating strength. .
In the present invention, the vibration-damping paint means a material containing at least the emulsion composition for vibration-damping material of the present invention and a filler. The vibration-damping paint may contain components other than the filler.

As the above-mentioned vibration-damping paint, for example, the solid content is preferably 40 to 90% by weight, more preferably 50 to 90% by weight, further preferably 100% by weight of the total amount of the vibration-damping paint. It is 60-90 mass%.
As a compounding quantity of the emulsion composition for damping materials in the said damping paint, the solid content of the emulsion composition for damping materials will be 10-60 mass% with respect to 100 mass% of solid contents of a damping paint, for example. It is preferable to set as described above, and more preferably 15 to 60% by mass.

The pH of the vibration-damping paint is preferably 7 to 11, and more preferably 7 to 9. The pH can be measured by the same method as described above.
The viscosity of the vibration-damping paint is preferably 100 to 2000 Pa · s, more preferably 200 to 1000 Pa · s, under the condition of 2 min ⁻¹ (= 2 rotations / minute). Moreover, it is preferable that it is 10-500 Pa.s under the conditions of 20 min < ^-1 > (= 20 rotation / min), More preferably, it is 30-300 Pa.s.
With such a viscosity, it is easy to apply to the base material and is suitable as a vibration-damping coating material free from dripping.
The viscosity of the vibration-damping paint can be measured by the same method as the viscosity of the emulsion composition for vibration damping materials described above.

Examples of other components that can be blended in the vibration-damping paint of the present invention include a filler, for example, a foaming agent; a pigment; a thickener; a solvent; an aqueous cross-linking agent; a gelling agent; Coloring agents; rust preventive pigments; plasticizers; stabilizers; wetting agents; antiseptics; antifoaming agents; anti-aging agents; antifungal agents; ultraviolet absorbers; More than seeds can be used.
In addition, said other component can be mixed with the emulsion composition for damping materials etc. using a butterfly mixer, a planetary mixer, a spiral mixer, a kneader, a dissolver etc., for example.

Examples of the filler include inorganic fillers such as calcium carbonate, kaolin, silica, talc, barium sulfate, alumina, iron oxide, titanium oxide, glass talk, magnesium carbonate, aluminum hydroxide, talc, diatomaceous earth, and clay; glass Examples thereof include flaky inorganic fillers such as flakes and mica; fibrous inorganic fillers such as metal oxide whiskers and glass fibers.
As a compounding quantity of a filler, it is preferable to set it as 50-700 mass% with respect to 100 mass% of solid content of the emulsion composition for damping materials, More preferably, it is 100-550 mass%.

When a particulate filler is used as the filler, the average particle diameter of the filler is preferably 0.5 to 50 μm. More preferably, it is 2 to 25 μm.
Examples of the particulate filler include calcium carbonate and titanium oxide.
When calcium carbonate is used as the filler, NS # 100, NN # 200, SS # 30 (manufactured by Nitto Flour Chemical Co., Ltd.), R heavy charcoal (manufactured by Maruo Calcium Co., Ltd.) have the preferable average particle diameter as described above. Is preferred.
The average particle size of the filler can be measured by a fully automatic particle size measuring device, and is a value of 50% by weight from the particle size distribution.

As said pigment, 1 type (s) or 2 or more types, such as the coloring agent mentioned later and a rust preventive pigment, can be used, for example. The blending amount of the pigment is preferably 50 to 700% by mass and more preferably 100 to 550% by mass with respect to 100% by mass of the solid content of the emulsion composition for vibration damping materials.

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.
The blending amount of the foaming agent is 0. 0% with respect to 100% by mass of the solid content of the emulsion composition for damping material, in order that the coating film of the damping material satisfies the above-described cross-sectional void ratio. It is preferable to set it as 4 to 8.0 mass%. More preferably, it is 0.6-7.0 mass%, More preferably, it is 0.8-6.0 mass%, Most preferably, it is 1.0-5.0 mass%.

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% by solid content with respect to 100 mass% of solid content of the emulsion composition for damping materials, More preferably, it is 0.05-1. It is 5 mass%, More preferably, it is 0.1-1 mass%.

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 the solid content concentration of the emulsion composition for damping materials in a damping paint may become the range mentioned above.

Examples of the aqueous crosslinking agent include oxazoline compounds such as Epocross WS-500, WS-700, K-2010, 2020, 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% by solid content with respect to 100 mass% of solid content of the emulsion composition for damping materials, for example, More preferably, it is 0.15- It is 15 mass%, More preferably, it is 0.5-15 mass%.
The water-based crosslinking agent may be added to the emulsion composition for a vibration damping material, or may be added at the same time when other components are blended as a vibration damping paint. By mixing a crosslinking agent with the emulsion composition for vibration damping material or the vibration damping paint, the toughness of the resin is improved, and as a result, sufficient high vibration damping properties are exhibited in a high temperature region. Among them, it is preferable to use an oxazoline compound.

Examples of the gelling agent include starch and agar.
Examples of the dispersant include inorganic dispersants such as sodium hexametaphosphate and sodium tripolyphosphate, and organic dispersants such as polycarboxylic acid-based dispersants.
Examples of the antifoaming agent include silicon-based antifoaming agents.
Examples of the colorant include organic or inorganic colorants such as titanium oxide, carbon black, dial, hansa yellow, benzine yellow, phthalocyanine blue, and quinacridone red.
Examples of the rust preventive pigment include a metal phosphate, a metal molybdate, and a metal borate.

As the other component, a polyvalent metal compound may be used. In this case, the multivalent metal compound improves the stability, dispersibility, heat drying property, and damping properties of the damping material formed from the damping coating. It does not specifically limit as a polyvalent metal compound, For example, zinc oxide, zinc chloride, zinc sulfate etc. are mentioned, These 1 type (s) or 2 or more types can be used.
Examples of the form of the polyvalent metal compound may include a powder, an aqueous dispersion, an emulsion dispersion, and the like. Especially, since the dispersibility in a vibration damping paint improves, it is preferable to use it 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% with respect to 100 mass% of solid content in the emulsion composition for damping materials, More preferably, it is 0.05. It is -3.5 mass%.

For example, the vibration-damping coating material can form a coating film that serves as a vibration-damping material by being applied to a substrate and dried. As a method for applying the vibration-damping paint to the substrate, for example, it can be applied using a brush, a spatula, an air spray, an airless spray, a mortar gun, a lysine gun or the like.

The thickness of the coating film of the vibration damping material of the present invention is preferably 1 to 5 mm. The coating film of the vibration damping material of the present invention can exhibit excellent vibration damping properties at any film thickness, but the coating film has excellent vibration damping properties and coating film strength. Is more preferably 1.5 to 4.5 mm.
It is also preferable that the surface density of the coating film after drying is coated to a 1.0~7.0kg / ^{m 2,} more preferably from 2.0~6.0kg / ^{m 2.} By using the vibration-damping coating material of the present invention, it is possible to obtain a coating film that hardly causes expansion and cracks during and after drying, and that does not easily cause the coating material on the inclined surface to slide off.
Thus, the coating method of the damping paint which coats and dries so that the film thickness of the coating film after drying becomes 1-5 mm, and the surface density of the coating film after drying is 2.0-6. A coating method in which coating is performed so as to be 0.0 kg / m ² and drying is also one aspect of the present invention.
The film thickness of the coating film can be measured with calipers.
The surface density of the coating film can be calculated from the application area and the dry weight of the applied coating film.

After applying the vibration-damping paint, the condition for drying to form a coating film may be heat-dried or room-temperature dried, but the vibration-damping paint in the present invention is excellent in heat-drying properties. From the viewpoint of efficiency, it is preferable to heat and dry. When the vibration-damping paint contains a foaming agent, it is preferable to dry the foaming agent at a temperature higher than the foaming temperature of the foaming agent in order to sufficiently exhibit the foaming effect of the foaming agent. The lower limit of the heat drying temperature is preferably 110 ° C. or higher, and more preferably 120 ° C. or higher. Moreover, before making it dry at temperatures, such as 110 degreeC or more, the process made to dry at 50-100 degreeC may be included.
Moreover, as an upper limit of the temperature of heat drying, it is preferable to set it as 210 degrees C or less, More preferably, it is 170 degrees C or less.

The vibration-damping paint of the present invention preferably has a glass transition temperature of 20 to 50 ° C. after drying. In order for the coating film to exhibit excellent vibration damping properties, it is necessary that the coating film is not too hard, and if the glass transition temperature of the coating film after drying the vibration damping coating is such a temperature, it is practical. Excellent vibration damping can be achieved in the temperature range. Since the glass transition temperature of the coating film of the vibration damping coating is affected by the content of components other than the polymer such as the pigment in addition to the glass transition temperature of the polymer contained in the vibration damping coating, By adjusting the content of the components, the glass transition temperature of the vibration-damping paint can be adjusted to the above-mentioned preferable range. The glass transition temperature of the coating film after drying is more preferably 25 to 45 ° C.
The glass transition temperature of the coating film after drying of the vibration-damping paint can be measured by the method described in Examples using a dynamic viscoelasticity measuring apparatus RSA-III (manufactured by TA Instruments) described in Examples.

When the above emulsion composition for damping material or damping coating is applied to damping material use, the damping property is measured by the loss factor of the film formed from the emulsion composition for damping material or damping coating. Can be evaluated.
The loss factor is usually expressed by η and indicates how much the vibration applied to the damping material is attenuated. The loss factor indicates that the higher the numerical value, the better the damping performance.
As a method for measuring the loss factor, a resonance method for measuring near the resonance frequency is generally used, and there are a half width method, an attenuation rate method, and a mechanical impedance method. In the above emulsion composition for damping material and damping coating, the loss factor of the film formed from the emulsion composition for damping material and damping coating is determined by the resonance method (3 dB method) using the cantilever method. It is preferable to measure. The measurement using the cantilever method can be performed using, for example, a CF-5200 FFT analyzer manufactured by Ono Sokki Co., Ltd.

The vibration damping material of the present invention is excellent in vibration damping properties and can be used for various applications, but also excellent in coating film strength in which coating film peeling and the like are suppressed. Can be suitably used. The vibration damping material of the present invention formed on such a vehicle steel plate is also one aspect of the present invention.

The vibration damping material of the present invention has the above-described configuration, and the coating film has a specific cross-sectional void ratio, so that it has excellent vibration damping properties and high coating film strength. It is a vibration damping material that can be suitably used in applications where coating-type vibration damping materials such as aircraft, electrical equipment, building structures, and construction equipment are used.

It is the conceptual diagram which showed the measuring method of the peeling strength in an Example.

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 weight” and “%” means “mass%”.

In the following production examples, various physical properties and the like were evaluated as follows.
<Average particle size>
The volume average particle diameter of the emulsion particles was measured using a particle size distribution measuring apparatus (“NICOMP Model 380” manufactured by Particle Sizing Systems) by a dynamic light scattering method.
<Nonvolatile content (N.V.)>
About 1 g of the obtained emulsion was weighed, and after 110 hours at 110 ° C. with a hot air dryer, 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 value at 25 ° C. was measured with a pH meter (“F-23” manufactured by Horiba, Ltd.).
<Viscosity>
Using a B-type rotational viscometer (“VISCOMETER TUB-10” manufactured by Toki Sangyo Co., Ltd.), the measurement was performed at 25 ° C. and 20 rpm.

<Number 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)
Measurement method: The measurement object is dissolved in THF so that the solid content is about 0.2% by mass, and the molecular weight is measured using an object obtained by filtration through a filter as a measurement sample.

<Glass glass transition temperature (Tg)>
The Tg of the polymer was calculated from the monomer composition used in each stage using the following calculation formula (1).

In addition, Tg calculated from the monomer composition used in all stages was described as “total Tg”.
Tg values of the respective homopolymers used for calculating the glass transition temperature (Tg) of the polymerizable monomer component by the above formula (1) are shown below.
Methyl methacrylate (MMA): 105 ° C
Styrene (St): 100 ° C
Butyl acrylate (BA): -56 ° C
2-ethylhexyl acrylate (2EHA): -70 ° C
Acrylic acid (AA): 95 ° C

Production Example 1
285 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, 285 parts of styrene, 280 parts of methyl methacrylate, 215 parts of 2-ethylhexyl acrylate, 200 parts of butyl acrylate, 20 parts of acrylic acid, 6 parts of t-dodecyl mercaptan, and hightenol 18E previously adjusted to a 20% aqueous solution were added to the dropping funnel. A monomer emulsion consisting of 150 parts (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 200 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 70 parts of the above monomer emulsion, 6.6 parts of 3% potassium persulfate aqueous solution and 5.0 parts of 2% sodium hydrogensulfite aqueous solution were added. Was added to initiate the initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 240 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 160 parts of a 3% aqueous potassium persulfate solution and 60 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 240 minutes, and the same temperature was maintained for 90 minutes after completion of the addition to complete the polymerization. After cooling the resulting reaction solution to room temperature, 22 parts of triethylamine and 3 parts of fine side HS-10 (trade name, manufactured by Tokyo Fine Co., Ltd., active ingredient 5%) were added, the non-volatile content was 54.1%, pH 8. The emulsion composition 1 for damping material having a viscosity of 350 mPa · s, a number average molecular weight of 22,000, and a molecular weight distribution (weight average molecular weight / number average molecular weight) of 3.1 was obtained.

Production Example 2
285 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, lathemul WX (trade name, Kao), which was previously adjusted to a 20% aqueous solution in 250 parts of styrene, 90 parts of butyl acrylate, 50 parts of 2-ethylhexyl acrylate, 10 parts of acrylic acid, 3.0 parts of t-dodecyl mercaptan 1st stage monomer emulsion consisting of 60 parts and 80 parts deionized water. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 50 parts of the monomer emulsion, 6.6 parts of 3% potassium persulfate aqueous solution and 5.0 parts of 2% sodium hydrogensulfite aqueous solution were added. Was added to initiate the initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 120 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 64 parts of a 3% aqueous potassium persulfate solution and 24 parts of a 2.3% aqueous sodium hydrogen sulfite solution were added dropwise uniformly over 120 minutes, and the same temperature was maintained for 60 minutes after completion of the addition. Next, 300 parts of styrene, 290 parts of 2-ethylhexyl acrylate, 10 parts of acrylic acid, 3.0 parts of t-dodecyl mercaptan, 90 parts of Latemle WX (trade name, manufactured by Kao Corporation) previously adjusted to a 20% aqueous solution in a dropping funnel And a second-stage monomer emulsion consisting of 120 parts of deionized water was added dropwise uniformly over 120 minutes. At the same time, 96 parts of a 3% aqueous potassium persulfate solution and 36 parts of a 2.3% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 120 minutes. After completion of the addition, the same temperature was maintained for 90 minutes to complete the polymerization. After cooling the obtained reaction liquid to room temperature, 20 parts of 2-dimethylethanolamine and 0.5 parts of proxel GXL (trade name, manufactured by Lonza, 20% active ingredient) were added, and the non-volatile content was 54.6%. The emulsion composition 2 for vibration damping materials having a pH of 8.0, a viscosity of 290 mPa · s, a number average molecular weight of 20000, and a molecular weight distribution of 2.0 was obtained.

Production Example 3
285 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, 350 parts of styrene, 380 parts of methyl methacrylate, 150 parts of 2-ethylhexyl acrylate, 100 parts of butyl acrylate, 20 parts of acrylic acid, 6 parts of t-dodecyl mercaptan, and Haitenol 18E previously adjusted to a 20% aqueous solution were added to the dropping funnel. A monomer emulsion consisting of 150 parts (trade name, manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) and 200 parts deionized water was charged. Next, while maintaining the internal temperature of the polymerization vessel at 80 ° C., 70 parts of the above monomer emulsion, 6.6 parts of 3% potassium persulfate aqueous solution and 5.0 parts of 2% sodium hydrogensulfite aqueous solution were added. Was added to initiate the initial polymerization. After 20 minutes, the remaining monomer emulsion was uniformly added dropwise over 240 minutes while maintaining the inside of the reaction system at 80 ° C. At the same time, 160 parts of a 3% aqueous potassium persulfate solution and 60 parts of a 2% aqueous sodium hydrogen sulfite solution were uniformly added dropwise over 240 minutes, and the same temperature was maintained for 90 minutes after completion of the addition to complete the polymerization. After cooling the obtained reaction liquid to room temperature, 22 parts of triethylamine and 3 parts of fine side HS-10 (trade name, manufactured by Tokyo Fine Co., Ltd., active ingredient 5%) were added, non-volatile content 54%, pH 8.3, An emulsion composition 3 for a vibration damping material having a viscosity of 320 mPa · s, a number average molecular weight of 21,000, and a molecular weight distribution of 3.1 was obtained.

Production Example 4
Except for not adding fine side HS-10, in the same manner as in Production Example 1, for damping material having non-volatile content of 53.9%, pH 8.2, viscosity of 300 mPa · s, number average molecular weight of 22000, molecular weight distribution of 3.1 Emulsion composition 4 was obtained.

Production Example 5
2. Nonvolatile content 53.8%, pH 8.5, viscosity 450 mPa · s, number average molecular weight 25000, molecular weight distribution 3. Other than not using 2% sodium bisulfite during initial polymerization and dropping. 0 emulsion composition 5 for damping material was obtained.

Production Example 6
Except for changing the concentration of sodium hydrogen sulfite used at the time of initial polymerization and dropping to 7.5%, in the same manner as in Production Example 1, the nonvolatile content was 54.0%, pH 8.3, viscosity 320 mPa · s, number average The emulsion composition 6 for vibration damping materials having a molecular weight of 24,000 and a molecular weight distribution of 3.0 was obtained.

Specific contents of each trade name used in the above Production Examples 1 to 6 are as follows.
<Isothiazoline compounds>
* Fine Side HS-10: Tokyo Fine Co., Ltd., active ingredient 5%, 2-methyl-4-isothiazolin-3-one (MIT)
* Proxel GXL: Lonza, 20% active ingredient, 1,2-benzisothiazolin-3-one (BIT)
<Emulsifier>
* Hightenol 18E: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., polyoxyethylene alkyl ether ammonium sulfate (anionic)
* Latemul WX: manufactured by Kao Corporation, polyoxyethylene polycyclic ammonium phenyl ether ammonium (anionic)

Example 1
The emulsion composition 1 for vibration damping materials obtained in Production Example 1 was blended as follows to obtain a vibration damping paint 1.
Emulsion composition for damping material 1 359 parts Calcium carbonate (NN # 200 ^{* 1} ) 620 parts Carbon black 1 part Starch 46.8 parts Dispersant (Aquaric DL-40S ^{* 2} ) 6 parts Thickener (Acryset WR- 650 ^{* 3} ) 4 parts antifoam (Nopco 8034L ^{* 4} ) 1 part foaming agent (Matsumoto Microsphere F-30 ^{* 5} ) 4 parts * 1: Filling material manufactured by Nitto Flour & Chemical Co., Ltd. (average particle size 20 μm)
* 2: 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 (main component: hydrophobic silicone + mineral oil) manufactured by San Nopco Co., Ltd.
* 5: Matsumoto Yushi Co., Ltd. foaming agent

Example 2 , Reference Example 1, Examples 4-7, Reference Examples 2-4 , Comparative Examples 1-4
In addition, the damping composition 2 to 10 and the comparison were made in the same manner as in Example 1 except that the emulsion composition for damping material to be used, the type and amount of the foaming agent, and the calcium carbonate amount were changed as shown in Table 1. Damping paints 1-4 were prepared.
The foaming agent F-50 used in Example 7 and Comparative Example 3 is Matsumoto Microsphere F-50 manufactured by Matsumoto Yushi Co., Ltd.

About the damping paint 1-10 obtained by the said Example 1 , 2, Reference Example 1, Examples 4-7, Reference Examples 2-4, and Comparative Examples 1-4, and the comparative damping paint 1-4, The glass transition temperature, the measurement of the cross-sectional porosity of the coating film, the evaluation of vibration damping properties, and the measurement of the peel strength of the coating film were performed by the following methods. The results are shown in Table 1. Table 1 also shows the average particle size, non-volatile content, pH, and viscosity of the emulsion composition for damping material used in each damping coating.

<Glass transition temperature of damping paint (Tg)>
A damping material sheet obtained by casting a damping coating with a coating film thickness of about 3 mm on a Teflon (R) sheet and drying under each drying condition is cut into a width of 5 mm, a length of 50 mm and a thickness of 3 mm. The glass transition temperature was measured using a dynamic viscoelasticity measuring device RSA-III (manufactured by TA Instruments) as a test piece. The dynamic viscoelasticity is measured at a three-point bending mode, a temperature increase rate of 3 ° C./minute, and a measurement rate of −20 to 100 ° C. did.
<Cross section porosity>
A damping material sheet was cast on a Teflon (R) sheet with a coating film thickness of about 3 mm and dried under each drying condition to obtain a damping material sheet. After cutting with a cutter knife to a depth of about 1 mm from the surface of the damping material sheet, the coating is cut with a cross section polisher (CP), and the resulting cross section is displayed on a digital microscope (Keyence Corporation). Manufactured by VHX-2000) to obtain an image. By analyzing the obtained image, the void portion and the other portion were binarized, and the area ratio of the void portion to the cross-sectional area was calculated.

<Vibration suppression test>
The obtained vibration-damping paint was applied to a cold-rolled steel plate (SPCC, width 15 mm × length 250 mm × thickness 1.5 mm) with a thickness of 3 mm, dried at 150 ° C. for 30 minutes, and surfaced on the cold-rolled steel plate. A damping material film having a density of 4.0 kg / m ² was formed. The vibration damping property was measured using a cantilever method (loss factor measurement system, Ono Sokki Co., Ltd.) and a loss factor at 25 ° C. by a resonance method (3 dB method). The greater the loss factor, the better the vibration damping.
<Coating film peel strength>
The peel strength was measured with a Kenken-type adhesive strength tester by the following method.
A 20 cm × 20 cm × 3 mm cold rolled steel plate (SPCC) was used as a substrate. The obtained vibration-damping paint was applied at a thickness of 3 mm, dried at 130 ° C. for 30 minutes with a hot air dryer, and then cooled to room temperature. As shown in FIG. 1, an attachment 3 having an adhesion area of 4.0 cm × 4.0 cm was attached to an anti-vibration paint 2 dried on a base material 1 with an epoxy resin adhesive 4 (Cemedine 1500, manufactured by Cemedine). Cured at 25 ° C for 4 days to harden the adhesive, and after making a notch 5 reaching the base material around the attachment with a cutter knife along the outer periphery of the attachment, the Kenken-type adhesive strength tester (Yamamotoko) With the heavy machine LPT-1500), the attachment 3 is pulled in the vertical direction 6 with respect to the surface of the base material 1 on which the coating film of the damping paint 2 is formed, and the coating film of the damping paint 2 is peeled off from the base material 1 The load (breaking load) necessary for the measurement was measured. The test temperature is 25 ° C., the loading speed of the Kenken-type adhesive strength tester is about 100 kPa / sec, and the peel strength is the obtained breaking load and the adhesion area between the attachment 3 and the vibration-damping paint 2 (= base material) The area of the coating film of the vibration-damping paint 2 peeled from 1) was determined by the following formula.
Peel strength (kPa) = (Fracture load (N) / Adhesion area (cm ² )) × 10

乾燥条件Ａ：１５０℃×３０分
乾燥条件Ｂ：８０℃×２０分＋１２０℃×３０分

Drying condition A: 150 ° C. × 30 minutes Drying condition B: 80 ° C. × 20 minutes + 120 ° C. × 30 minutes

1: Base material 2: Damping paint 3: Attachment 4: Epoxy resin adhesive 5: Cut with a cutter knife 6: Direction of pulling of attachment with Kenken adhesive strength tester

Claims (4)

A damping material is a coating of damping paint containing a port Rimmer emulsion and filler,
The vibration-damping paint further contains an isothiazoline-based compound,
The vibration damping material has a cross-sectional porosity of a coating film of 10 to 36 %. The polymer emulsion contains 60% by mass or more of a polymer containing a monomer unit derived from a (meth) acrylic acid ester and / or a monomer unit derived from styrene based on the whole polymer contained in the polymer emulsion. The vibration damping material according to claim 1. The vibration damping material according to claim 1 or 2, wherein the glass transition temperature of the dried coating film is 20 to 50 ° C. It forms on the steel plate for vehicles, The damping material in any one of Claims 1-3 characterized by the above-mentioned.

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