composition

Abstract

To provide a composition comprising polymer particles that enables formation of a film superior in adhesion and resistance to BHM.SOLUTION: A composition according to the present invention, comprises polymer particles (A), a compound (B) having a cyano group, and a liquid medium (C), wherein the polymer particles (A) contain a polymer including repeating units derived from methyl (meth)acrylate, and the polymer particles (A) have glass transition points (Tg) in ranges of -10°C to 55°C and 80°C to 200°C, and wherein the content of the compound (B) in the composition is 0.1 ppm and 1000 ppm.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a composition containing polymer particles. [Background technology]

[0002] Compositions containing polymer particles such as latex are widely used as binders in fields such as paper coating, carpet backsizing, wood products such as plywood and veneer, battery electrodes, and tire cords (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-124473 [Patent Document 2] International Publication No. 2021 / 006211 Summary of the Invention [Problem to be solved by the invention]

[0004] Compositions containing such polymer particles are used in a variety of applications, such as those described above. For example, when the composition is applied to a substrate to form a coating film, the coating film must have sufficient adhesion to prevent peeling from the substrate. Furthermore, when the composition is mixed with other components to form a floor polish film or the like, the coating film must have sufficient black heel mark resistance (also referred to herein as "BHM resistance") to prevent rubber marks from being left on shoe soles.

[0005] Some aspects of the present invention provide a composition containing polymer particles that can form a film having excellent adhesion and BHM resistance. [Means for solving the problem]

[0006] One aspect of the composition of the present invention is Polymer particles (A), a compound (B) having a cyano group; A composition comprising a liquid medium (C), the polymer particles (A) contain a polymer having a repeating unit derived from methyl (meth)acrylate, the polymer particles (A) have a glass transition point (Tg) in the range of -10°C to 55°C and in the range of 80°C to 200°C, The content of the compound (B) in the composition is 0.1 ppm to 1000 ppm.

[0007] In one embodiment of the composition, The polymer particles (A) may further contain a repeating unit derived from an α,β-unsaturated nitrile compound.

[0008] In any of the above-described embodiments of the composition, The polymer particles (A) may further contain a repeating unit derived from an unsaturated carboxylic acid.

[0009] In any of the above-described embodiments of the composition, The compound (B) may be acrylonitrile. [Effects of the Invention]

[0010] According to the composition of the present invention, a film having excellent adhesion and BHM resistance can be produced. DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will be described in detail below. Note that the present invention is not limited to the following embodiments, and various modifications are also included within the scope of the present invention.

[0012] In this specification, "(meth)acrylic" refers to "acrylic" or "methacrylic".

[0013] In this specification, a numerical range described using "X to Y" means that the range includes the numerical value X as the lower limit and the numerical value Y as the upper limit.

[0014] 1. Composition A composition according to one embodiment of the present invention is a composition containing polymer particles (A), a compound (B) having a cyano group, and a liquid medium (C), wherein the polymer particles (A) contain a polymer having a repeating unit derived from methyl (meth)acrylate, the polymer particles (A) have glass transition points (Tg) in the ranges of -10°C to 55°C and 80°C to 200°C, respectively, and the content of the compound (B) in the composition is 0.1 ppm to 1000 ppm. Components that may be contained in the composition according to this embodiment will be described in detail below.

[0015] 1.1. Polymer particles (A) The composition according to this embodiment contains polymer particles (A). The polymer particles (A) contain a polymer having repeating units derived from methyl (meth)acrylate. The composition according to this embodiment is preferably in the form of a latex in which the polymer particles (A) are dispersed in a liquid medium (C). The shape of the polymer particles (A) is preferably core-shell particles having a core and a shell with properties different from those of the core.

[0016] Hereinafter, the repeating units contained in the polymer constituting the polymer particles (A), the physical properties of the polymer constituting the polymer particles (A), and the synthesis method will be described in that order.

[0017] 1.1.1. Repeating Unit The polymer constituting the polymer particles (A) contains a repeating unit (Ma) (hereinafter also referred to as "repeating unit (Ma)") derived from methyl (meth)acrylate. The polymer constituting the polymer particles (A) preferably further contains a repeating unit (Mb) (hereinafter also referred to as "repeating unit (Mb)") represented by the following general formula (1): [ka] (In formula (1), R 1 represents a hydrogen atom or a methyl group, and R 2 represents an alkyl group having 4 to 10 carbon atoms.

[0018] The content of the repeating unit (Ma) is preferably 3 to 50% by mass, when the total of the repeating units contained in the polymer constituting the polymer particles (A) is taken as 100% by mass. The lower limit of the content of the repeating unit (Ma) is more preferably 5% by mass, and particularly preferably 8% by mass. The upper limit of the content of the repeating unit (Ma) is more preferably 40% by mass, and particularly preferably 30% by mass.

[0019] When the polymer particles (A) are core-shell particles, the shell preferably has a repeating unit (Ma), which improves the film strength and makes it easier to obtain a film with excellent BHM resistance.

[0020] Specific examples of the monomer that provides the repeating unit (Mb) include alkyl (C4-C10) (meth)acrylate esters such as n-butyl (meth)acrylate, isobutyl (meth)acrylate, n-amyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, nonyl (meth)acrylate, and decyl (meth)acrylate, and the monomer may be one or more selected from these. Of these alkyl (C4-C10) (meth)acrylate esters, one or more selected from n-butyl (meth)acrylate and 2-ethylhexyl (meth)acrylate are preferred.

[0021] The content of the repeating unit (Mb) is preferably 5 to 75% by mass, when the total of the repeating units contained in the polymer constituting the polymer particles (A) is 100% by mass. The lower limit of the content of the repeating unit (Mb) is more preferably 10% by mass, and particularly preferably 20% by mass. The upper limit of the content of the repeating unit (Mb) is more preferably 60% by mass, and particularly preferably 50% by mass.

[0022] When the polymer particles (A) are core-shell particles, the core preferably has a repeating unit (Mb).

[0023] The polymer constituting the polymer particles (A) may contain, in addition to the repeating units (Ma) and (Mb), repeating units derived from other monomers copolymerizable therewith. Examples of such repeating units include repeating units derived from α,β-unsaturated nitrile compounds, repeating units derived from unsaturated carboxylic acids, repeating units derived from aromatic vinyl compounds, repeating units derived from unsaturated carboxylic acid esters (excluding the repeating units (Ma) and (Mb)), and repeating units derived from α,β-unsaturated amides.

[0024] Specific examples of the α,β-unsaturated nitrile compound include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, α-ethylacrylonitrile, vinylidene cyanide, etc., and the compound may be one or more selected from these. Among these, the compound may be one or more selected from acrylonitrile and methacrylonitrile, and more preferably acrylonitrile.

[0025] The content of the repeating unit derived from the α,β-unsaturated nitrile compound is preferably 5 to 40% by mass when the total of the repeating units contained in the polymer constituting the polymer particles (A) is taken as 100% by mass. The lower limit of the content of the repeating unit derived from the α,β-unsaturated nitrile compound is more preferably 8% by mass, and particularly preferably 10% by mass. The upper limit of the content of the repeating unit (Mb) is more preferably 35% by mass, and particularly preferably 10% by mass. The content is preferably 30 mass %.

[0026] When the polymer particles (A) are core-shell particles, the core preferably has a repeating unit derived from an α,β-unsaturated nitrile compound. Furthermore, when the polymer particles (A) are core-shell particles, the shell preferably does not have a repeating unit derived from an α,β-unsaturated nitrile compound. When the core has a repeating unit derived from an α,β-unsaturated nitrile compound with high cohesive strength, the polymer particles (A) can achieve both good adhesion and strength, making it easier to obtain a film with excellent adhesion and BHM resistance.

[0027] Specific examples of unsaturated carboxylic acids include monocarboxylic acids and dicarboxylic acids such as acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, and itaconic acid, and the unsaturated carboxylic acid may be one or more selected from these. In particular, the unsaturated carboxylic acid may be one or more selected from acrylic acid, methacrylic acid, and itaconic acid.

[0028] The content of the repeating units derived from the unsaturated carboxylic acid is preferably 6 to 25 mass%, and more preferably 8 to 20 mass%, when the total amount of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0029] When the polymer particles (A) are core-shell particles, it is preferable that at least one of the core and shell portions has a repeating unit derived from an unsaturated carboxylic acid, and it is more preferable that both the core and shell portions have a repeating unit derived from an unsaturated carboxylic acid.

[0030] When the polymer particles (A) are core-shell particles, the content of repeating units derived from unsaturated carboxylic acid in the core portion is preferably 5 to 15 mass%, and more preferably 6 to 12 mass%, when the total amount of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0031] When the polymer particles (A) are core-shell particles, the content of repeating units derived from unsaturated carboxylic acids in the shell portion is preferably 1 to 10 mass%, and more preferably 2 to 8 mass%, when the total amount of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0032] Specific examples of aromatic vinyl compounds include styrene, α-methylstyrene, p-methylstyrene, vinyltoluene, chlorostyrene, 1-ethyl-2-vinylbenzene, divinylbenzene, sodium p-styrenesulfonate, etc., and the aromatic vinyl compound may be one or more selected from these. Of the above, styrene is particularly preferred as the aromatic vinyl compound.

[0033] The content of repeating units derived from aromatic vinyl compounds is preferably 5 to 45 mass%, and more preferably 10 to 30 mass%, when the total amount of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0034] The unsaturated carboxylic acid ester is preferably a (meth)acrylic acid ester other than methyl (meth)acrylate and alkyl (C4-C10) (meth)acrylate ester. Specific examples of the (meth)acrylic acid ester include ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, benzyl (meth)acrylate, hydroxymethyl (meth)acrylate, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, ethylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, tetramethyl ( ... trimethylolpropane di(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, and the like can be mentioned, and one or more selected from these can be used.

[0035] The content of the repeating units derived from the unsaturated carboxylic acid ester (excluding the repeating units (Ma) and (Mb)) is preferably 0.1 to 10 mass%, and more preferably 0.5 to 5 mass%, when the total of the repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0036] Specific examples of the α,β-unsaturated amide compound include (meth)acrylamide, N,N-dimethyl(meth)acrylamide, and N,N-diethyl(meth)acrylamide, and the compound may be one or more selected from these.

[0037] The content of the repeating units derived from the α,β-unsaturated amide compound is preferably 0.1 to 20 mass%, and more preferably 0.5 to 15 mass%, when the total amount of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0038] When the polymer particles (A) are core-shell particles, the total content of repeating units contained in the polymer constituting the core portion is preferably 55 to 95 mass%, and more preferably 60 to 90 mass%, when the total of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0039] When the polymer particles (A) are core-shell particles, the total content of repeating units contained in the polymer constituting the shell portion is preferably 5 to 45 mass%, and more preferably 10 to 40 mass%, when the total of repeating units contained in the polymer constituting the polymer particles (A) is taken as 100 mass%.

[0040] 1.1.2. Physical properties of polymers 1.1.2.1.Number average particle size The number average particle diameter of the polymer particles (A) is preferably in the range of 30 nm to 600 nm, more preferably in the range of 40 nm to 200 nm. When the number average particle diameter of the polymer particles (A) is in the above range, the surface of the resulting coating film becomes smooth, and a coating film with excellent scratch resistance can be produced.

[0041] The number-average particle size of the polymer particles (A) is the particle size (D50) value at which the cumulative frequency of the number of particles, starting from the smallest particle, reaches 50% when the particle size distribution is measured using a particle size distribution analyzer based on the light scattering method. Examples of such particle size distribution analyzers include the Coulter LS230, LS100, and LS13 320 (all manufactured by Beckman Coulter, Inc.) and the FPAR-1000 (manufactured by Otsuka Electronics Co., Ltd.). These particle size distribution analyzers can evaluate not only the primary particles of polymer particles but also secondary particles formed by aggregation of the primary particles. Therefore, the particle size distribution measured by these particle size distribution analyzers can be used as an indicator of the dispersion state of the polymer particles.

[0042] 1.1.2.2.Glass transition temperature The polymer constituting the polymer particles (A) has a glass transition point (Tg) in the temperature range of -10°C to 55°C and a glass transition point (Tg) in the temperature range of 80°C to 200°C when measured by differential scanning calorimetry (DSC) in accordance with JIS K7121:2012. Specifically, the polymer particles (A) are phase-separated like a core-shell structure, and have a polymer phase having a glass transition point (Tg) in the temperature range of -10°C to 55°C and a polymer phase having a glass transition point (Tg) in the temperature range of 80°C to 200°C. It is preferable that the polymer particles (A) contain a core made of a polymer having a glass transition temperature (Tg) in the temperature range of -10°C to 55°C, and a shell made of a polymer having a glass transition temperature (Tg) in the temperature range of 80°C to 200°C.

[0043] 1.1.3. Method for synthesizing polymer particles (A) The method for synthesizing the polymer particles (A) is not particularly limited. For example, when producing core-shell particles, a two-stage polymerization method may be used in which a polymer constituting the core portion is obtained by emulsion polymerization as a first-stage polymerization, and then the shell portion is synthesized by performing emulsion polymerization in a second stage by changing the monomer composition, for example.

[0044] The emulsion polymerization step is carried out by emulsifying and dispersing the monomer components, an emulsifier, a polymerization initiator, and a chain transfer agent in an aqueous medium by stirring, followed by radical polymerization. Each material used in the emulsion polymerization step will be described below.

[0045] Examples of the monomer component used in the emulsion polymerization step include methyl (meth)acrylate, alkyl (C4-C10) (meth)acrylate esters, α,β-unsaturated nitrile compounds, unsaturated carboxylic acids, aromatic vinyl compounds, unsaturated carboxylic acid esters other than methyl (meth)acrylate and alkyl (C4-C10) (meth)acrylate esters, and α,β-unsaturated amide compounds.

[0046] Methyl (meth)acrylate is preferably used in the second-stage emulsion polymerization. The content of methyl (meth)acrylate in 100% by mass of all monomer components is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, and particularly preferably 8 to 30% by mass.

[0047] The (C4-C10) alkyl (meth)acrylate ester is preferably used in the first-stage emulsion polymerization. The content of the (C4-C10) alkyl (meth)acrylate ester in 100% by mass of all monomer components is preferably 5 to 75% by mass, more preferably 10 to 60% by mass, and particularly preferably 20 to 50% by mass.

[0048] The α,β-unsaturated nitrile compound is preferably used in the first-stage emulsion polymerization. The content of the α,β-unsaturated nitrile compound in 100% by mass of all monomer components is preferably 5 to 40% by mass, more preferably 8 to 35% by mass, and particularly preferably 10 to 30% by mass.

[0049] The unsaturated carboxylic acid is preferably used in at least one of the first and second emulsion polymerization stages. The acid value of the polymer constituting the polymer particles (A) can be adjusted by appropriately adjusting the content of the unsaturated carboxylic acid in the first and second stages. The content of the unsaturated carboxylic acid is preferably 6 to 25% by mass, more preferably 8 to 20% by mass, based on 100% by mass of all monomer components.

[0050] Specific examples of the emulsifier include anionic surfactants such as sulfate salts of higher alcohols, aliphatic sulfates, alkylbenzene sulfonates, alkyl diphenyl ether disulfonates, aliphatic sulfonates, aliphatic carboxylates, aliphatic phosphate salts, aliphatic phosphate salts, dehydroabietic acid salts, naphthalene sulfonic acid-formalin condensates, sulfate salts or phosphate salts having a (poly)alkoxy structure, and polymerizable ether sulfate-type ammonium salts; nonionic surfactants such as alkyl esters of polyethylene glycol, alkylphenyl ethers of polyethylene glycol, and alkyl ethers of polyethylene glycol; perfluorobutyl sulfonates, perfluoroalkyl group-containing alkyl esters, and the like; Examples of the surfactant include fluorine-based surfactants such as phosphate esters, perfluoroalkyl group-containing carboxylates, and perfluoroalkylethylene oxide adducts, and one or more surfactants selected from these can be used.

[0051] Specific examples of polymerization initiators include water-soluble polymerization initiators such as lithium persulfate, potassium persulfate, sodium persulfate, ammonium persulfate, and 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] tetrahydrate; and oil-soluble polymerization initiators such as cumene hydroperoxide, benzoyl peroxide, tert-butyl hydroperoxide, acetyl peroxide, diisopropylbenzene hydroperoxide, 1,1,3,3-tetramethylbutyl hydroperoxide, azobisisobutyronitrile, and 1,1'-azobis(cyclohexanecarbonitrile). Among these, potassium persulfate, sodium persulfate, ammonium persulfate, cumene hydroperoxide, or tert-butyl hydroperoxide is preferred. The proportion of the polymerization initiator used is not particularly limited, but should be determined appropriately taking into account the monomer composition, pH of the polymerization reaction system, and the combination of other additives.

[0052] Specific examples of chain transfer agents include alkyl mercaptans such as n-hexyl mercaptan, n-octyl mercaptan, tert-octyl mercaptan, n-dodecyl mercaptan, tert-dodecyl mercaptan, and n-stearyl mercaptan; xanthogen compounds such as dimethyl xanthogen disulfide and diisopropyl xanthogen disulfide; thiuram compounds such as terpinolene, tetramethylthiuram disulfide, tetraethylthiuram disulfide, and tetramethylthiuram monosulfide; 2,6-di-tert-butyl-4-methylphenol, styrenated phenol, etc. allyl compounds such as allyl alcohol; halogenated hydrocarbon compounds such as dichloromethane, dibromomethane, and carbon tetrabromide; vinyl ether compounds such as α-benzyloxystyrene, α-benzyloxyacrylonitrile, and α-benzyloxyacrylamide; as well as triphenylethane, pentaphenylethane, acrolein, methacrolein, thioglycolic acid, 2-ethylhexyl thioglycolate, thiomalic acid, 2-ethylhexyl thioglycolate, and α-methylstyrene dimer, and one or more selected from these can be used.

[0053] The emulsion polymerization step is preferably carried out under conditions of a polymerization temperature of 40 to 80°C and a polymerization time of 2 to 4 hours.

[0054] After the emulsion polymerization is completed, it is preferable to neutralize the dispersion by adding a neutralizing agent so that the pH of the dispersion is about 5 to 10. The neutralizing agent used is not particularly limited, but examples include metal hydroxides such as sodium hydroxide and potassium hydroxide, ammonia, and amine compounds. Setting the pH of the dispersion in the range of 5 to 10 improves the blend stability of the dispersion, and the pH of the dispersion is preferably 6 to 9, and more preferably 7 to 8.5. Setting the total solids concentration in the emulsion polymerization step to 50% by mass or less allows the reaction to proceed with good dispersion stability, but the total solids concentration in the emulsion polymerization step is preferably 45% by mass or less, and more preferably 40% by mass or less. Furthermore, concentration after the neutralization treatment can further improve particle stability while achieving a high solids concentration.

[0055] 1.2. Compounds having a cyano group (B) The composition according to this embodiment contains a compound (B) having a cyano group (also simply referred to as "compound (B)" in this specification). The content of compound (B) in the composition according to this embodiment is 0.1 ppm to 1000 ppm, and preferably 0.1 ppm to 500 ppm. A compound (B) with high polarity has a high affinity with water. For this reason, When the content of compound (B) in the composition is within the above range, it is presumed that the wettability and adhesion of the resulting coating film can be improved.

[0056] Compound (B) is preferably an organic compound having a cyano group, and more preferably an α,β-unsaturated nitrile compound. Specific examples of compound (B) include acrylonitrile, methacrylonitrile, α-chloroacrylonitrile, dichloroacetonitrile, vinylidene cyanide, acetonitrile, propiononitrile, isobutyronitrile, pentanenitrile, hexanedinitrile, phenylacetonitrile, 4-cyano-1-cyclohexene, pent-2-en-4-ynenitrile, and oct-6-en-2-ynenitrile. Among these, one or more selected from acrylonitrile and methacrylonitrile are preferred, and acrylonitrile is more preferred.

[0057] 1.3. Liquid Medium (C) The composition according to this embodiment contains a liquid medium (C). The liquid medium (C) is preferably an aqueous medium containing water. The aqueous medium may contain a non-aqueous medium other than water. Examples of such non-aqueous medium include amide compounds, hydrocarbons, alcohols, ketones, esters, amine compounds, lactones, sulfoxides, and sulfone compounds, and one or more selected from these may be used. When the liquid medium (C) contains water and a non-aqueous medium, it is preferable that the total mass of the liquid medium (C) is 100% by mass, and more preferably 90% by mass or more of the liquid medium (C) is water. By using an aqueous medium as the liquid medium (C) in the composition according to this embodiment, the degree of adverse impact on the environment is reduced and the safety for handling workers is increased.

[0058] The content of the non-aqueous medium in the aqueous medium is preferably 10% by mass or less, more preferably 5% by mass or less, and particularly preferably substantially free of the non-aqueous medium, based on 100% by mass of the aqueous medium. Here, "substantially free of the non-aqueous medium" means that the non-aqueous medium is not intentionally added as a liquid medium, and the composition may contain a non-aqueous medium that is inevitably mixed in when preparing the composition.

[0059] 1.4. Other additives The composition according to the present embodiment may contain additives other than the above-mentioned components, as needed, such as thickeners, fillers, preservatives, and pH adjusters.

[0060] <Thickener> Examples of thickeners include cellulose compounds such as carboxymethyl cellulose, methyl cellulose, and hydroxypropyl cellulose; ammonium salts or alkali metal salts of the above cellulose compounds; polycarboxylic acids such as poly(meth)acrylic acid and modified poly(meth)acrylic acid; alkali metal salts of the above polycarboxylic acids; polyvinyl alcohol (co)polymers such as polyvinyl alcohol, modified polyvinyl alcohol, and ethylene-vinyl alcohol copolymers; and water-soluble polymers such as saponified copolymers of vinyl esters with unsaturated carboxylic acids such as (meth)acrylic acid, maleic acid, and fumaric acid. Among these, alkali metal salts of carboxymethyl cellulose and alkali metal salts of poly(meth)acrylic acid are particularly preferred.

[0061] Commercially available thickeners include alkali metal salts of carboxymethylcellulose such as CMC1120, CMC1150, CMC2200, CMC2280, and CMC2450 (all manufactured by Daicel Corporation).

[0062] When the composition according to this embodiment contains a thickener, the amount of the thickener used is preferably 5% by mass or less, and more preferably 0.1 to 3% by mass, based on the total solid content of the composition.

[0063] <Filler> The composition according to this embodiment may improve the hardness of the coating film when formed into a coating film by containing a filler. Examples of the filler include organic fillers and inorganic fillers. Specific examples of the organic filler include polyamide fine particles such as nylon 6, nylon 12, and nylon 66; fluorine-based fine particles such as tetrafluoroethylene and vinylidene fluoride; olefin-based fine particles such as polyethylene and polypropylene; polyester-based fine particles such as polyethylene terephthalate and polyethylene naphthalate; crosslinked particles such as divinylbenzene and polyfunctional acrylates; and rubber fine particles such as natural rubber, isoprene rubber, and acrylic rubber. Specific examples of the inorganic filler include fused spherical silica, fumed silica, sol-gel silica, aluminum oxide, aluminum hydroxide, calcium carbonate, calcium hydroxide, barium sulfate, barium carbonate, magnesium oxide, magnesium hydroxide, and other inorganic fillers derived from minerals such as talc and mica. One or more of these can be used.

[0064] <Preservative> The composition according to this embodiment can suppress the growth of bacteria, mold, etc. and the generation of foreign substances when the composition is stored by containing a preservative. Specific examples of the preservative include 1,2-benzisothiazolin-3-one, 2-methyl-4,5-trimethylene-4-isothiazolin-3-one, 2-methyl-4-isothiazolin-3-one, 5-chloro-2-methyl-4-isothiazolin-3-one, N-n-butyl-1,2-benzisothiazolin-3-one, 2-n-octyl-4-isothiazolin-3-one, 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one, etc. One or more of these can be used.

[0065] <pH adjuster> The composition according to this embodiment may be adjusted to a pH of 5 to 9 by adding a pH adjuster. Adjusting the pH to 5 to 9 may improve the dispersion stability of the polymer particles (A) and may result in excellent storage stability. Examples of pH adjusters include acidic compounds such as hydrochloric acid, phosphoric acid, sulfuric acid, acetic acid, and formic acid; and basic compounds such as potassium hydroxide, ethylenediamine, monoethanolamine, TMAH (tetramethylammonium hydroxide), TEAH (tetraethylammonium hydroxide), and ammonia.

[0066] In the present invention, pH refers to hydrogen ion exponent, and its value can be measured using a commercially available pH meter (for example, a tabletop pH meter manufactured by Horiba, Ltd.) under conditions of 25°C and 1 atmosphere.

[0067] 1.5. Method for producing the composition The composition according to this embodiment may be prepared by mixing the above-mentioned components, and may be prepared, for example, by the method described in JP-A-2007-332202.

[0068] 2. Working Example The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In the examples, "parts" and "%" are by mass unless otherwise specified.

[0069] 2.1 Example 1 2.1.1. Preparation of composition containing polymer particles (A) After the inside of a 0.5 L separable flask was purged with nitrogen, 150.0 parts by mass of ion-exchanged water and 0.3 parts by mass of ammonium persulfate (APS) were charged. The internal temperature was adjusted to 70°C while stirring, and an emulsion (prepared in a separate container by mixing and stirring 30.0 parts by mass of ion-exchanged water, 24.0 parts by mass of acrylonitrile (AN), 38.0 parts by mass of butyl acrylate (BA), 7.0 parts by mass of methacrylic acid (MAA), 1.5 parts by mass of sodium dodecyl sulfate (SDS), and 1 part by mass of n-dodecyl mercaptan (NDM)) was added dropwise over 2 hours to produce a core portion. After the dropwise addition was completed, the internal temperature was adjusted to 80°C, and an emulsion that had been prepared in advance in a separate container by mixing and stirring 10.0 parts by mass of ion-exchanged water, 24.0 parts by mass of methyl methacrylate (MMA), 6.0 parts by mass of methacrylic acid (MAA), and 0.5 parts by mass of sodium dodecyl sulfate (SDS) was added dropwise over 1 hour to produce the shell portion. After the dropwise addition was completed, the mixture was stirred at 80°C for another 2 hours and then cooled to 40°C. 1.0 part by mass of 25% aqueous ammonia (manufactured by Taisei Kako Co., Ltd., product name "25% aqueous ammonia") and acrylonitrile (AN) as compound (B) were added so as to have the content shown in Table 1 below, and ion-exchanged water was added so that the content of polymer particles became 30% by mass, thereby obtaining a composition.

[0070] 2.1.2.Physical property measurements The polymer particles contained in the composition obtained above were measured using a differential scanning calorimeter (DSC) in accordance with JIS K7121:2012, and two glass transition temperatures (Tg) were observed, at 30°C and 140°C.

[0071] Furthermore, the particle size distribution of the obtained composition was measured using a particle size distribution measuring device (manufactured by Otsuka Electronics Co., Ltd., model "FPAR-1000") that uses dynamic light scattering as its measurement principle, and the number average particle diameter (D50) was calculated from the particle size distribution, and the number average particle diameter (D50) was found to be 40 nm.

[0072] 2.1.3.Evaluation of adhesion (Evaluation method) The composition prepared above was applied to a glass substrate to a film thickness of 200 μm and dried at 70° C. for 2 minutes to prepare an evaluation sample. Cellophane tape (manufactured by Nichiban Co., Ltd.) was applied to this evaluation sample, rubbed with a finger, and then the tape was peeled off. The state of the coating film in this area was visually observed and evaluated according to the following criteria. (Evaluation criteria) A: No peeling of the coating is observed, so the adhesion is judged to be very good. B: The peeled area of ​​the coating film is less than 50% and is judged to be good because it can be used in practical applications. C: The area of ​​peeled coating is 50% or more, making it difficult to put into practical use and judged as poor.

[0073] 2.1.4. Evaluation of Black Heel Mark (BHM) Resistance When the composition is mixed with other ingredients depending on the application and used as a floor polish film, etc., if the rubber marks from the soles of shoes tend to remain on the coating, it will not be possible to maintain a good appearance and it may become unusable for practical purposes. For this reason, the black heel mark (BHM) resistance was evaluated using the following method. (Evaluation method) A Zn chelate solution was prepared in advance by mixing 24 g of ion-exchanged water, 14 g of zinc oxide, 12 g of ammonium carbonate, 20 g of aminoacetic acid, and 30 g of 25% aqueous ammonia. The Zn chelate solution was added so that 0.5 chemical equivalents of Zn was contained relative to the unsaturated carboxylic acid (methacrylic acid) used as a monomer in "2.1.1. Preparation of a composition containing polymer particles (A)" in 100 g of the composition prepared above, and after stirring for 2 hours, diethylene glycol mononitrate was added. Ethyl ether and tri(2-n-butoxyethyl)phosphate were mixed in a mass ratio of 4:1, and the minimum film-forming temperature (MFT) was adjusted to 5°C or less. Next, ion-exchanged water was added to the mixture to adjust the solids content to 19% by mass, thereby preparing a composition for evaluating black heel mark (BHM) resistance. The composition for evaluation thus obtained was applied in an amount of 10 g / m 2The test sample was prepared by applying the test solution to a Homogenia Style (TOLI Corporation, product number "MS Plain MS5626") and drying it at 23°C for one hour three times. The test sample was placed as flooring in a high-traffic area (traffic volume = 50-100 people / day) for 10 days, and the degree of black heel mark (BHM) adhesion was visually observed and evaluated according to the following criteria. The results are shown in Table 1 below. (Evaluation criteria) The AA:BHM is 20 or less, there are no restrictions on the components to be mixed when producing the coating film, and it can be used in practical applications, so it is judged to be particularly good. A: The BHM is 21 to 40, and it is judged to be very good as it can be used in practice. B: The BHM is 41 to 60, and although care must be taken with the ingredients mixed when preparing the coating film, it is judged to be good as it can be used in practice. C: The number of BHMs is 61 or more, and the product is deemed to be unsuitable for practical use and therefore is deemed to be defective.

[0074] 2.2. Examples 2 to 8 and Comparative Examples 1 to 5 Compositions were prepared and evaluated in the same manner as in Example 1, except that in the above "2.1.1. Preparation of composition containing polymer particles (A)", the types and amounts of the monomer, emulsifier, and chain transfer agent were changed as shown in Table 1 below. The results are shown in Table 1 below.

[0075] 2.3.Evaluation Results Table 1 below shows the compositions used in each example and comparative example, as well as the evaluation results.

[0076] [Table 1]

[0077] The abbreviations for each component in Table 1 above represent the following products or reagents: <Monomer> MMA: Methyl methacrylate (manufactured by Mitsubishi Chemical Corporation, product name "Acryester M") ) BA: Butyl acrylate (manufactured by Mitsubishi Chemical Corporation, product name "Butyl acrylate") MAA: Methacrylic acid (manufactured by Mitsubishi Chemical Corporation, product name "MAA") AN: Acrylonitrile (manufactured by Mitsubishi Chemical Corporation, product name "Acrylonitrile") <Chain transfer agent> NDM: n-dodecyl mercaptan (manufactured by Kaneda Co., Ltd., product name "N-dodecyl mercaptan") <Polymerization initiator> APS: Ammonium persulfate (manufactured by Mitsubishi Gas Chemical Company, Inc., product name "Ammonium persulfate") <Emulsifier> SDS: Sodium dodecyl sulfate (Kao Corporation, product name "Emeral 2FG")

[0078] The evaluation results in Table 1 above show that the compositions according to the present invention shown in Examples 1 to 8 can produce films with excellent adhesion and BHM resistance. In contrast, the compositions shown in Comparative Examples 1 and 5 have only one polymer particle with a lower glass transition point, and although they have excellent adhesion, they do not produce films with satisfactory BHM resistance. The composition shown in Comparative Example 2 has a lower polymer particle glass transition point of 60°C, and it was found that the adhesion of the film was impaired. The composition shown in Comparative Example 3 contains 0 ppm of compound (B), and it was found that a film with unsatisfactory adhesion and BHM resistance was produced. The composition shown in Comparative Example 4 contains 7,000 ppm of compound (B), and it was found that a film with unsatisfactory adhesion and BHM resistance was produced.

[0079] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the present invention includes configurations that are substantially the same as the configurations described in the embodiments (for example, configurations with the same function, method, and result, or configurations with the same purpose and effect). The present invention also includes configurations in which non-essential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that achieve the same effects or purposes as the configurations described in the embodiments. The present invention also includes configurations in which publicly known technology is added to the configurations described in the embodiments.

Claims

1. Polymer particles (A), a compound (B) having a cyano group; A composition comprising a liquid medium (C), the polymer particles (A) contain a polymer having a repeating unit derived from methyl (meth)acrylate, the polymer particles (A) have a glass transition point (Tg) in the range of −10° C. to 55° C. and in the range of 80° C. to 200° C., The composition, wherein the content of the compound (B) in the composition is 0.1 ppm to 1000 ppm.

2. 2. The composition according to claim 1, wherein the polymer particles (A) further contain a repeating unit derived from an α,β-unsaturated nitrile compound.

3. 3. The composition according to claim 1, wherein the polymer particles (A) further contain a repeating unit derived from an unsaturated carboxylic acid.

4. 3. The composition according to claim 1 or claim 2, wherein the compound (B) is acrylonitrile.

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