JP2018059008A - Resin emulsion for sealer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin emulsion for a sealer for forming a coating film having comprehensively excellent water permeability, blocking resistance, impregnation adhesion and frost damage resistance, a sealer containing the resin emulsion for the sealer, and a coating composed of the sealer. Provided is an inorganic building material having a membrane. SOLUTION: The resin emulsion for a sealer containing a polymer having a weight average molecular weight of 10,000 to 80,000, and the content of a styrene-based monomer in all the monomer components used as a raw material of the resin emulsion for the sealer. Is 40 to 90% by mass. [Selection diagram] None

Description

  The present invention relates to a resin emulsion for sealers. More specifically, the present invention relates to, for example, a resin emulsion for a sealer useful for a sealer used for inorganic building materials such as ceramic building materials and a method for producing the same, a sealer containing the resin emulsion for a sealer, and a coating comprising the sealer. The present invention relates to an inorganic building material having a film. The resin emulsion for sealers of the present invention can be suitably used for, for example, factory coating, that is, an undercoating paint used when coating inorganic building materials in a factory line.

  In recent years, from the viewpoint of environmental protection, an aqueous two-component undercoat coating composition mainly composed of a copolymer emulsion (for example, see Patent Document 1) and an aqueous undercoat coating composition containing a resin emulsion (for example, Patent Document 2). Have been proposed). In these undercoat coating compositions, since the coating film is formed by fusing resin particles, it is necessary to use a large amount of a film-forming aid when the glass transition temperature of the resin is high. However, when a large amount of film-forming aid is used, the coating resistance contained in the coating film decreases the blocking resistance, so that the coating film is easily damaged and the surface protection of the object to be coated is insufficient. Or the appearance of the object to be coated may be impaired.

  As an aqueous coating composition with improved blocking resistance, an aqueous resin composition in which particles having a multilayer structure are dispersed has been proposed (for example, see Patent Document 3). However, since the water-based resin composition needs to have a high glass transition temperature of the shell portion of the particles in order to impart blocking resistance, it has the disadvantage of being inferior in film forming property and water permeability of the coating film. is there.

  Therefore, in order to improve the film forming property and the water permeability of the coating film, it is conceivable to lower the molecular weight of the polymer. However, when the molecular weight of the polymer is lowered, there is a disadvantage that the frost resistance is lowered.

Japanese Patent Laid-Open No. 2001-262053 JP 2001-335735 A JP 2002-012816 A

  The present invention has been made in view of the prior art, and is a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in water permeation resistance, blocking resistance, impregnation adhesion, and frost damage resistance, and for the sealer. It is an object to provide a sealer containing a resin emulsion and an inorganic building material having a coating film made of the sealer.

The present invention
(1) A resin emulsion for a sealer containing a polymer having a weight average molecular weight of 10,000 to 80,000, wherein the content of styrene monomer in all monomer components used as a raw material of the resin emulsion for the sealer is 40 to 90% by mass of a resin emulsion for a sealer,
(2) A sealer comprising the resin emulsion for a sealer according to (1),
(3) An inorganic building material having a coating film comprising the sealer according to (2), and (4) a method for producing a resin emulsion for a sealer containing a polymer having a weight average molecular weight of 10,000 to 80,000, The sealer resin emulsion contains a polymer having a weight average molecular weight of 10,000 to 80,000, and the content of styrene monomer in all monomer components used as a raw material of the sealer resin emulsion is 40. It is related with the manufacturing method of the resin emulsion for sealers characterized by adjusting to -90 mass%.

  According to the present invention, a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, adhesion to impregnation and frost damage resistance, a sealer containing the sealer resin emulsion, and the sealer An inorganic building material having a coating film is provided.

  As described above, the resin emulsion for sealer of the present invention is a resin emulsion for sealer containing a polymer having a weight average molecular weight of 10,000 to 80,000, and all monomer components used as raw materials for the resin emulsion for sealer The content rate of the styrene-type monomer in is 40-90 mass%.

  Since the resin emulsion for sealers of the present invention has the above-mentioned constituent requirements, it is possible to form a coating film that is comprehensively excellent in water permeability resistance, blocking resistance, impregnation adhesion, and frost damage resistance.

  In the present invention, “impregnation adhesion” means the property that the coating film is in close contact with the substrate after the inorganic building material on which the coating film is formed is immersed in water.

  The sealer resin emulsion of the present invention contains, for example, a polymer having a weight average molecular weight of 10,000 to 80,000 in the sealer resin emulsion, and all monomer components used as a raw material for the sealer resin emulsion. It can obtain by adjusting the content rate of the styrene-type monomer in 40 to 90 mass%.

  The resin emulsion for sealers of the present invention has one major feature in that it contains a polymer having a weight average molecular weight of 10,000 to 80,000. Since the resin emulsion for sealers of the present invention contains a polymer having a weight average molecular weight of 10,000 to 80,000 (hereinafter referred to as a low molecular weight polymer), water permeability resistance, blocking resistance, impregnation adhesion and The excellent effect of forming a coating film excellent in frost resistance is obtained.

  The weight average molecular weight of the low molecular weight polymer is 10,000 or more from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. It is preferably 20,000 or more, more preferably 30,000 or more, and further preferably 40,000 or more, for a sealer that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion, it is 80,000 or less, preferably 70,000 or less, more preferably 60,000 or less, and still more preferably 50,000 or less.

  In the present specification, the weight average molecular weight of the polymer is a value obtained by gel permeation chromatography (GPC) under the following conditions.

・ System: Tosoh Corporation, trade name: HLC-8320GPC
・ Developing solvent: Tetrahydrofuran (THF) [Wako Pure Chemical Industries, Ltd., special grade]
・ Solvent flow rate: 0.350 mL / min
Standard sample: TSK-GEL standard polystyrene [manufactured by Tosoh Corporation, trade name: PS-oligomer kit, product number: 0005214, 0005202, 0005211, 0005207, 0005205, 0005209 and 0005213]
-Column configuration on the measurement side: manufactured by Tosoh Corp., product name: TSK-GEL superMultipore HZ-M 6.0 × 150, connected in series-Column configuration on the reference side: manufactured by Tosoh Corp., product name: TSK- GEL SuperH-RC 6.0 × 150
-Column temperature: 40 ° C
・ Detector: Differential refractometer (RI)
Measurement method: The measurement object is dissolved in tetrahydrofuran so that the nonvolatile content is about 0.2% by mass, filtered through a filter, and then the weight average molecular weight is measured using the obtained solution.

In the present specification, the weight average molecular weight of the low molecular weight polymer is a value obtained by the following method.
Based on the results of measuring the standard substance for the calibration curve by gel permeation chromatography (GPC), a calibration curve (a graph in which the vertical axis indicates the molecular weight and the horizontal axis indicates the outflow time) is prepared, and the weight average molecular weight is calculated from the calibration curve. The outflow time (ta) corresponding to 80,000 and the outflow time (tb) corresponding to a weight average molecular weight of 10,000 are determined. Next, from the result obtained from the GPC measurement of the resin emulsion, the outflow corresponding to the weight average molecular weight 10,000 determined from the calibration curve from the outflow time (ta) corresponding to the weight average molecular weight 80,000 determined from the calibration curve. The weight average molecule of the low molecular weight polymer in the measurement region until the time (tb) is determined using the HLC-8320GPC.

  The content of the low molecular weight polymer in the total polymer contained in the resin emulsion for sealer of the present invention forms a coating film that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer, it is preferably at least 1 area%, more preferably at least 5 area%, even more preferably at least 10 area%, even more preferably at least 20 area%, even more preferably at least 30 area%. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, preferably 60 area% or less, more preferably 50 area%. Hereinafter, it is more preferably 40% by area or less.

In addition, in this specification, the content rate of the low molecular weight polymer in all the polymers contained in the resin emulsion for sealers is a value when calculated | required with the following method.
Based on the results of measuring the standard substance for the calibration curve by gel permeation chromatography (GPC), a calibration curve (a graph in which the vertical axis indicates the molecular weight and the horizontal axis indicates the outflow time) is prepared, and the weight average molecular weight is calculated from the calibration curve. The outflow time (ta) corresponding to 80,000 and the outflow time (tb) corresponding to a weight average molecular weight of 10,000 are determined. Next, from the result obtained from the GPC measurement of the resin emulsion, the outflow corresponding to the weight average molecular weight 10,000 determined from the calibration curve from the outflow time (ta) corresponding to the weight average molecular weight 80,000 determined from the calibration curve. The area of the measurement region up to time (tb) and the area of the measurement region in the total outflow time are obtained. From the area determined above, the content of the low molecular weight polymer in the total polymer contained in the resin emulsion for sealer is expressed by the formula:
[Content of low molecular weight polymer (area%) in all polymers contained in resin emulsion for sealer]
= [Area of the measurement region from the outflow time (ta) corresponding to the weight average molecular weight of 80,000 obtained from the calibration curve to the outflow time (tb) corresponding to the weight average molecular weight of 10,000 obtained from the calibration curve / Area of measurement area in total outflow time] × 100
Ask based on.

As the form of the resin emulsion for a sealer of the present invention containing a polymer having a weight average molecular weight of 10,000 to 80,000, for example,
(1) A resin emulsion for a sealer containing emulsion particles having a plurality of layers, and having a resin layer composed of a low molecular weight polymer in any one of the plurality of layers,
(2) A resin emulsion for a sealer containing a plurality of emulsion particles having different weight average molecular weights, wherein at least one of the plurality of emulsion particles having different weight average molecular weights is an emulsion particle composed of a low molecular weight polymer. Although a form etc. are mentioned, this invention is not limited only to this illustration.

  Among the forms of the resin emulsion for sealers, from the viewpoint of obtaining a resin emulsion for sealers that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, (1) It is a resin emulsion for a sealer containing emulsion particles having a plurality of layers, and preferably has a resin layer composed of a low molecular weight polymer in any one of the plurality of layers.

  First, the (1) resin emulsion for sealers containing emulsion particles having a plurality of layers, and a mode in which any one of the plurality of layers has a resin layer composed of a low molecular weight polymer will be described.

  A resin emulsion for a sealer containing emulsion particles having a plurality of layers can be obtained, for example, by subjecting a monomer component used as a raw material of the emulsion particles to multistage emulsion polymerization.

  The number of resin layers constituting the emulsion particles is preferably from 2 to 2 from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in water permeation resistance, blocking resistance, impregnation adhesion, and frost damage resistance. There are 5 layers, more preferably 2 and 3 layers, still more preferably 3 layers. In addition, the boundary of each resin layer does not necessarily need to be clear, and adjacent resin layers may be mixed with each other.

  In the following description, for the sake of convenience, the resin layer constituting the emulsion particles having a plurality of layers will be described as being divided into a central layer and layers other than the central layer. When the emulsion particles have two resin layers, an inner layer and an outer layer, the inner layer means a central layer, and the outer layer means a layer other than the central layer. When the emulsion particles have three resin layers, an inner layer, an intermediate layer, and an outer layer, the inner layer means a central layer, and the intermediate layer and the outer layer mean layers other than the central layer.

  (1) A resin emulsion for a sealer containing emulsion particles having a plurality of layers, and having a resin layer composed of a low molecular weight polymer in any one of the plurality of layers, From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in blocking resistance, adhesion to impregnation and frost damage resistance, a layer other than the central layer is composed of a low molecular weight polymer. When the emulsion particles have three or more resin layers, the outermost layer of the layers other than the central layer, that is, the outermost layer of the emulsion particles is composed of a low molecular weight polymer. A form having a resin layer is more preferable.

  When the emulsion particles have three or more resin layers, the resin layer composed of a low molecular weight polymer may be included only in the outermost layer among the layers other than the center layer. You may have in layers other than the outermost layer and outermost layer among layers. Among these forms, it is composed of a low molecular weight polymer from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. It is preferable that the resin layer has only the outermost layer among the layers other than the center layer.

  In addition, the resin layer comprised from a low molecular weight polymer may have only in layers other than a center layer, and may have it in layers other than a center layer and a center layer.

  Examples of a method for forming a resin layer composed of a low molecular weight polymer in any layer of emulsion particles having a plurality of layers include, for example, multi-stage emulsion polymerization of monomer components used as raw materials for the emulsion particles Examples thereof include a method of emulsion polymerization of a monomer component used as a raw material for a resin layer composed of a low molecular weight polymer in the presence of a chain transfer agent, but the present invention is limited only to such examples. It is not something.

  The order of mixing the chain transfer agent and the monomer component is arbitrary. For example, the chain transfer agent may be added to the monomer component and mixed. And may be mixed.

  Examples of chain transfer agents include mercapto group-containing compounds such as octyl mercaptan, dodecyl mercaptan, tert-dodecyl mercaptan, mercaptoethanol; thioglycolic acid, methyl thioglycolate, ethyl thioglycolate, propyl thioglycolate, thioglycolic acid Butyl, tert-butyl thioglycolate, 2-ethylhexyl thioglycolate, octyl thioglycolate, isooctyl thioglycolate, decyl thioglycolate, dodecyl thioglycolate, 3-mercapto-1-propanol, 3-mercapto-1, Examples include 3-propanediol, ethylene glycol thioglycolate, neopentyl glycol thioglycolate, and pentaerythritol thioglycolate. It is not limited only to the illustrated that. These chain transfer agents may be used alone or in combination of two or more. Among these chain transfer agents, octyl thioglycolate, dodecyl thioglycolate are used from the viewpoint of obtaining a resin emulsion for a sealer that forms a film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. Mercaptans and tert-dodecyl mercaptans are preferred, and octyl thioglycolate is more preferred.

  The amount of the chain transfer agent per 100 parts by mass of all monomer components used as the raw material for the emulsion particles forms a coating film that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer, it is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, and is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coated film, the amount is preferably 1 part by mass or less, more preferably 0.8 part by mass or less, and still more preferably 0.5 part by mass or less.

  Further, the amount of the chain transfer agent per 100 parts by mass of the monomer component used as a raw material of the resin layer composed of the low molecular weight polymer present in any layer of the emulsion particles having a plurality of layers is From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in heat resistance, blocking resistance, impregnation adhesion and frost damage resistance, preferably 0.1 parts by mass or more, more preferably 0.3 parts by mass Above, more preferably 0.5 parts by mass or more, preferably from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. Is 5 parts by mass or less, more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less.

  The sealer resin emulsion of the present invention has another major feature in that the content of the styrene monomer in all monomer components used as a raw material for the sealer resin emulsion is 40 to 90% by mass. . The resin emulsion for sealers of the present invention has a water permeability resistance and blocking resistance because the content of styrene monomer in all monomer components used as a raw material for the resin emulsion for sealers is 40 to 90% by mass. The film has an excellent effect of forming a coating film which is comprehensively excellent in heat resistance, impregnation adhesion and frost damage resistance.

  Examples of the styrenic monomer include styrene, α-methylstyrene, p-methylstyrene, tert-methylstyrene, chlorostyrene, vinyltoluene, and the like, but the present invention is limited only to such examples. is not. These styrenic monomers may be used alone or in combination of two or more. Styrene monomers have functional groups such as alkyl groups such as methyl and tert-butyl groups, nitro groups, nitrile groups, alkoxyl groups, acyl groups, sulfone groups, hydroxyl groups, and halogen atoms in the benzene ring. May be. Among these styrene monomers, styrene is preferable from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film having excellent water permeability, blocking resistance, impregnation adhesion, and frost damage resistance.

  The content of the styrene monomer in all monomer components used as a raw material for the resin emulsion for sealer of the present invention is a coating excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a film, it is 40% by mass or more, preferably 50% by mass or more, more preferably 60% by mass or more, and further preferably 70% by mass or more. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in impregnation adhesion and frost damage resistance, it is 90% by mass or less, preferably 85% by mass or less, and more preferably 80% by mass or less.

  As the monomer component used as a raw material for the resin emulsion for a sealer of the present invention, a monomer other than the styrene monomer (hereinafter simply referred to as “other monomer”) can be used.

  The content of other monomers in all monomer components used as a raw material for the resin emulsion for sealers of the present invention is a coating that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a film, it is 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, and has water permeability resistance, blocking resistance, impregnation adhesion and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a generally excellent coating film, it is 60% by mass or less, preferably 50% by mass or less, more preferably 40% by mass or less, and further preferably 30% by mass or less.

  Other monomers include, for example, alkyl (meth) acrylates, carboxyl group-containing monomers, silane group-containing monomers, hydroxyl group-containing (meth) acrylates, nitrogen atom-containing monomers, and styrene monomers Aromatic monomers, oxo group-containing monomers, fluorine atom-containing monomers, epoxy group-containing monomers, UV-absorbing monomers, UV-stable monomers, and the like. Is not limited to such examples. These monomers may be used alone or in combination of two or more. Among these other monomers, alkyl (meth) is used from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. Acrylate and carboxyl group-containing monomers are preferred.

  In the present specification, “(meth) acrylate” means “acrylate” or “methacrylate”, “(meth) acryl” means “acryl” or “methacryl”, and “(meth) acryloyl” means It means “acryloyl” or “methacryloyl”.

  Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert-butyl (meth) acrylate, and sec-butyl (meth). Alkyl having 1 to 18 carbon atoms in an ester group such as acrylate, 2-ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, n-octyl (meth) acrylate, tridecyl (meth) acrylate, n-lauryl (meth) acrylate Although (meth) acrylate etc. are mentioned, this invention is not limited only to this illustration. These alkyl (meth) acrylates may be used alone or in combination of two or more. Among these alkyl (meth) acrylates, from the viewpoint of obtaining a resin emulsion for a sealer that forms a film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, the carbon of the alkyl group An alkyl (meth) acrylate having a number of 1 to 8 is preferred, 2-ethylhexyl (meth) acrylate is more preferred, and 2-ethylhexyl acrylate is more preferred.

  The content of the alkyl (meth) acrylate in all monomer components used as a raw material for the resin emulsion for sealer of the present invention is a coating having excellent water permeability, blocking resistance, impregnation adhesion and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a film, it is preferably 5% by mass or more, more preferably 10% by mass or more, and still more preferably 15% by mass or more, water permeability resistance, blocking resistance, impregnation adhesion and From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in frost damage resistance, it is preferably 45% by mass or less, more preferably 40% by mass or less, and further preferably 35% by mass or less.

  Examples of the carboxyl group-containing monomer include (meth) acrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid, maleic anhydride, and other carboxyl group-containing aliphatic monomers. The invention is not limited to such examples. These carboxyl group-containing monomers may be used alone or in combination of two or more. Among these carboxyl group-containing monomers, from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance, (meta) Acrylic acid is preferred.

  The content of the carboxyl group-containing monomer in all monomer components used as a raw material for the resin emulsion for sealer of the present invention is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film, the content is preferably 1% by mass or more, more preferably 2% by mass or more, and further preferably 3% by mass or more. Water resistance, blocking resistance, impregnation adhesion From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in frost damage resistance, it is preferably 10% by mass or less, more preferably 8% by mass or less, and further preferably 5% by mass or less.

  Examples of the silane group-containing monomer include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri (methoxyethoxy) silane, γ- (meth) acryloyloxypropyltrimethoxysilane, 2-styrylethyltrimethoxysilane, vinyltri Examples include chlorosilane, γ- (meth) acryloyloxypropylhydroxysilane, and γ- (meth) acryloyloxypropylmethylhydroxysilane, but the present invention is not limited to such examples. These silane group-containing monomers may be used alone or in combination of two or more.

  Examples of the hydroxyl group-containing (meth) acrylate include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, and 4-hydroxy Examples include hydroxyl group-containing (meth) acrylates having 1 to 18 carbon atoms in the ester group such as butyl (meth) acrylate, but the present invention is not limited to such examples. These hydroxyl group-containing (meth) acrylates may be used alone or in combination of two or more.

  Examples of the nitrogen atom-containing monomer include (meth) acrylamide, diacetone (meth) acrylamide, N-monomethyl (meth) acrylamide, N-monoethyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N -N-propyl (meth) acrylamide, N-isopropyl (meth) acrylamide, methylenebis (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide, dimethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, (meth) acrylamide compounds such as diacetone (meth) acrylamide, nitrogen such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate Child-containing (meth) acrylate compounds, N- vinylpyrrolidone, but like (meth) acrylonitrile, the present invention is not limited only to those exemplified. These nitrogen atom-containing monomers may be used alone or in combination of two or more.

  Examples of the aromatic monomer other than the styrene monomer include aralkyl (meth) acrylate, but the present invention is not limited to such examples. Examples of the aralkyl (meth) acrylate include aralkyl having 7 to 18 carbon atoms such as benzyl (meth) acrylate, phenylethyl (meth) acrylate, methylbenzyl (meth) acrylate, naphthylmethyl (meth) acrylate and the like. Although (meth) acrylate etc. are mentioned, this invention is not limited only to this illustration. These aromatic monomers other than the styrene monomer may be used alone or in combination of two or more.

  Examples of the oxo group-containing monomer include (di) ethylene glycol (methoxy) (meta) such as ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, and diethylene glycol methoxy (meth) acrylate. ) Acrylate and the like, but the present invention is not limited to such examples. These oxo group-containing monomers may be used alone or in combination of two or more.

  Examples of the fluorine atom-containing monomer include fluorine atom-containing alkyl having 2 to 6 carbon atoms in an ester group such as trifluoroethyl (meth) acrylate, tetrafluoropropyl (meth) acrylate, and octafluoropentyl (meth) acrylate. Although (meth) acrylate etc. are mentioned, this invention is not limited only to this illustration. These fluorine atom-containing monomers may be used alone or in combination of two or more.

  Examples of the epoxy group-containing monomer include epoxy group-containing (meth) acrylates such as glycidyl (meth) acrylate, but the present invention is not limited to such examples. These epoxy group-containing monomers may be used alone or in combination of two or more.

  Examples of the UV-absorbing monomer include benzotriazole-based UV-absorbing monomers and benzophenone-based UV-absorbing monomers, but the present invention is not limited to such examples. These ultraviolet absorbing monomers may be used alone or in combination of two or more.

  Examples of the benzotriazole-based UV-absorbing monomer include 2- [2′-hydroxy-5 ′-(meth) acryloyloxymethylphenyl] -2H-benzotriazole, 2- [2′-hydroxy-5′- (Meth) acryloyloxyethylphenyl] -2H-benzotriazole, 2- [2′-hydroxy-5 ′-(meth) acryloyloxymethylphenyl] -5-tert-butyl-2H-benzotriazole, 2- [2 ′ -Hydroxy-5 '-(meth) acryloylaminomethyl-5'-tert-octylphenyl] -2H-benzotriazole, 2- [2'-hydroxy-5'-(meth) acryloyloxypropylphenyl] -2H-benzo Triazole, 2- [2'-hydroxy-5 '-(meth) acryloyloxyhex Ruphenyl] -2H-benzotriazole, 2- [2′-hydroxy-3′-tert-butyl-5 ′-(meth) acryloyloxyethylphenyl] -2H-benzotriazole, 2- [2′-hydroxy-3 ′ -Tert-butyl-5 '-(meth) acryloyloxyethylphenyl] -5-chloro-2H-benzotriazole, 2- [2'-hydroxy-5'-tert-butyl-3'-(meth) acryloyloxyethyl Phenyl] -2H-benzotriazole, 2- [2′-hydroxy-5 ′-(meth) acryloyloxyethylphenyl] -5-chloro-2H-benzotriazole, 2- [2′-hydroxy-5 ′-(meta ) Acrylyloxyethylphenyl] -5-cyano-2H-benzotriazole, 2- [2'-hydride Xyl-5 ′-(meth) acryloyloxyethylphenyl] -5-tert-butyl-2H-benzotriazole, 2- [2′-hydroxy-5 ′-(β- (meth) acryloyloxyethoxy) -3′- tert-butylphenyl] -4-tert-butyl-2H-benzotriazole and the like, but the present invention is not limited to such examples. These benzotriazole-based UV-absorbing monomers may be used alone or in combination of two or more.

  Examples of the benzophenone-based UV-absorbing monomer include 2-hydroxy-4- (meth) acryloyloxybenzophenone, 2-hydroxy-4- [2-hydroxy-3- (meth) acryloyloxy] propoxybenzophenone, 2- Hydroxy-4- [2- (meth) acryloyloxy] ethoxybenzophenone, 2-hydroxy-4- [3- (meth) acryloyloxy-2-hydroxypropoxy] benzophenone, 2-hydroxy-3-tert-butyl-4- Examples include [2- (meth) acryloyloxy] butoxybenzophenone, but the present invention is not limited to such examples. These benzophenone-based ultraviolet absorbing monomers may be used alone or in combination of two or more.

  Examples of UV-stable monomers include 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine. 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine, 4- (meth) acryloyl-1-methoxy-2,2,6,6-tetramethylpiperidine, 4-cyano- 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 1- (meth) acryloyl-4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4-croto Noylamino-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-1,2,2,6,6-pentamethylpiperidine, 4-sia -4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 4-crotonoyloxy-2,2,6,6-tetramethylpiperidine, 1- (meth) acryloyl-4-cyano- Examples include 4- (meth) acryloylamino-2,2,6,6-tetramethylpiperidine, 1-crotonoyl-4-crotonoyloxy-2,2,6,6-tetramethylpiperidine and the like. However, the present invention is not limited to such examples. These ultraviolet stable monomers may be used alone or in combination of two or more.

  In the following, for convenience, it contains emulsion particles having a resin layer of a layer other than the center layer and the center layer, which is a preferred embodiment of the resin emulsion for sealers of the present invention, and the center layer contains a styrenic monomer. It is formed of a polymer (I) obtained by emulsion polymerization of the monomer component A to be contained, and the layers other than the central layer are formed by emulsion polymerization of the monomer component B in the presence of a chain transfer agent. The sealer resin emulsion in which the content of the styrenic monomer in all monomer components formed of the polymer (II) and used as the raw material of the sealer resin emulsion is 40 to 90% by mass will be described.

  In addition, an intermediate layer resin layer formed from a polymer other than the low molecular weight polymer (II) may be formed in a layer other than the central layer as long as the object of the present invention is not impaired. . In this case, the monomer component used as the raw material for the resin layer of the intermediate layer can be the same type of monomer as the monomer used for the monomer component.

  The resin emulsion for a sealer of the present invention is obtained by, for example, subjecting the monomer component A containing a styrene monomer to emulsion polymerization to form a central layer composed of the obtained polymer (I), and then the central layer. When forming a layer other than the central layer composed of the low molecular weight polymer (II) by emulsion polymerization of the monomer component B in the presence of a chain transfer agent, it is used as a raw material for the resin emulsion for the sealer. It can obtain by adjusting the content rate of the styrene-type monomer in all the monomer components obtained to 40-90 mass%.

  The polymer (I) forming the center layer is obtained by emulsion polymerization of the monomer component A containing a styrene monomer.

  Examples of the styrene monomer used in the monomer component A include the same styrene monomers. Styrene monomers may be used alone or in combination of two or more. Among the styrenic monomers, styrene is preferable from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance.

  The content of the styrenic monomer in the monomer component A is from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. , Preferably 40% by mass or more, more preferably 50% by mass or more, further preferably 60% by mass or more, and still more preferably 70% by mass or more. Water permeability resistance, blocking resistance, impregnation adhesion and frost damage resistance From the viewpoint of obtaining a resin emulsion for a sealer that forms a generally excellent coating film, the content is 100% by mass or less.

  Therefore, the monomer component A may be composed of only a styrenic monomer, and forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for use in the styrene-based resin, preferably 0 to 60% by mass, more preferably 0 to 50% by mass, further preferably 0 to 40% by mass, and still more preferably 0 to 30% by mass. Monomers other than the monomer may be contained.

  Examples of the monomer other than the styrenic monomer include the same types of monomers as the other monomers. Monomers other than styrenic monomers may be used alone or in combination of two or more.

  As a method for emulsion polymerization of the monomer component A, for example, an emulsifier is dissolved in an aqueous medium containing water and a water-soluble organic solvent such as lower alcohol such as methanol and water, and the mixture is simply heated and stirred. Examples include a method in which the monomer component A and the polymerization initiator are dropped, a method in which the monomer component A previously emulsified using an emulsifier and water is dropped in water or an aqueous medium, and the like. It is not limited only to the method. In addition, what is necessary is just to set the quantity of a medium suitably in consideration of the non volatile matter amount contained in the resin emulsion obtained.

  Examples of the emulsifier include an anionic emulsifier, a nonionic emulsifier, a cationic emulsifier, an amphoteric emulsifier, and a polymer emulsifier. These emulsifiers may be used alone or in combination of two or more.

  Examples of the anionic emulsifier include polyoxyethylene styrenated phenyl ether sulfates such as polyoxyethylene styrenated phenyl ether sulfate [eg, Daiten Kogyo Seiyaku Co., Ltd., trade name: Hytenol NF-08]; Alkyl sulfate salts such as ammonium dodecyl sulfate and sodium dodecyl sulfate; alkyl sulfonate salts such as ammonium dodecyl sulfonate, sodium dodecyl sulfonate and sodium alkyl diphenyl ether disulfonate; alkyl aryl sulfonate salts such as ammonium dodecyl benzene sulfonate and sodium dodecyl naphthalene sulfonate; polyoxy Ethylene alkyl sulfonate salt; polyoxyethylene alkyl sulfate salt; Oxyethylene alkyl aryl sulfate salts; dialkyl sulfosuccinates; aryl sulfonic acid-formalin condensates; fatty acid salts such as ammonium laurate and sodium stearate; bis (polyoxyethylene polycyclic phenyl ether) methacrylate sulfonate salts, propenyl-alkyl sulfosuccinates Sulfuric acid ester having an allyl group such as acid ester salt, (meth) acrylic acid polyoxyethylene sulfonate salt, (meth) acrylic acid polyoxyethylene phosphonate salt, sulfonate salt of allyloxymethylalkyloxypolyoxyethylene, or a salt thereof ; Sulfate salt of allyloxymethylalkoxyethyl polyoxyethylene, polyoxyalkylene alkenyl ether sulfate ammonium salt, polyoxyethylene Alkyl ether sulfate [e.g., Kao Corp., trade name: LATEMUL WX-A, etc.] Although the like, the present invention is not limited only to those exemplified.

  Nonionic emulsifiers include, for example, polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, condensate of polyethylene glycol and polypropylene glycol, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, fatty acid monoglyceride, ethylene oxide and aliphatic Although the condensate with an amine etc. are mentioned, this invention is not limited only to this illustration.

  Examples of the cationic emulsifier include alkylammonium salts such as dodecylammonium chloride, but the present invention is not limited to such examples.

  Examples of amphoteric emulsifiers include betaine ester type emulsifiers, but the present invention is not limited to such examples.

  Examples of the polymer emulsifier include poly (meth) acrylates such as sodium polyacrylate; polyvinyl alcohol; polyvinyl pyrrolidone; polyhydroxyalkyl (meth) acrylates such as polyhydroxyethyl acrylate; single polymers constituting these polymers. Although the polymer etc. which use a 1 or more types of monomer of a monomer as a copolymerization component are mentioned, this invention is not limited only to this illustration.

  The reactive emulsifier can be preferably used from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. Of these, non-nonylphenyl emulsifiers are preferred from the viewpoint of environmental protection.

  Examples of the reactive emulsifier include propenyl-alkylsulfosuccinic acid ester salt, (meth) acrylic acid polyoxyethylene sulfonate salt, polyoxyethylene alkylpropenyl phenyl ether ammonium sulfate [for example, trade name: manufactured by Daiichi Kogyo Seiyaku Co., Ltd. Aqualon HS-10, Aqualon BC-10, etc.], sulfonate salts of allyloxymethylalkyloxypolyoxyethylene (for example, Dairon Kogyo Seiyaku Co., Ltd., trade name: Aqualon KH-10, etc.), allyloxymethylnonylphenoxy Sulphonate salt of ethyl hydroxypolyoxyethylene [for example, manufactured by ADEKA, trade name: Adekaria soap SE-10, etc.], allyloxymethylalkoxyethyl hydroxypolyoxyethylene sulfate salt [for example, (strain Made by ADEKA, trade names: Adekari Soap SR-10, SR-30, etc.], bis (polyoxyethylene polycyclic phenyl ether) methacrylated sulfonate salt [for example, manufactured by Nippon Emulsifier Co., Ltd., trade name: Antox MS- 60, etc.], allyloxymethylalkoxyethylhydroxypolyoxyethylene [for example, manufactured by ADEKA, trade name: Adekaria soap ER-20, etc.], polyoxyethylene alkylpropenyl phenyl ether [for example, Daiichi Kogyo Seiyaku Co., Ltd. Product name: Aqualon RN-20, etc.], allyloxymethylnonylphenoxyethylhydroxypolyoxyethylene [for example, product made by ADEKA, product name: Adecalia Soap NE-10, etc.] The invention is limited to only such examples No. Any of these reactive emulsifiers may be used alone or in combination of two or more.

  The amount of the emulsifier per 100 parts by mass of the monomer component A is preferably 0.5 parts by mass or more, more preferably 1 part by mass or more, further preferably 2 parts by mass or more, from the viewpoint of improving the polymerization stability. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, preferably 15 parts by mass or less, more preferably 10 parts by mass or less, More preferably, it is 5 mass parts or less.

  When polymerizing the monomer component A, a polymerization initiator can be used. Examples of the polymerization initiator include azobisisobutyronitrile, 2,2-azobis (2-methylbutyronitrile), 2,2-azobis (2,4-dimethylvaleronitrile), 2,2-azobis ( Azo compounds such as 2-diaminopropane) hydrochloride, 4,4-azobis (4-cyanovaleric acid), 2,2-azobis (2-methylpropionamidine); persulfates such as potassium persulfate and ammonium persulfate; Examples of the peroxide include peroxides such as hydrogen peroxide, benzoyl peroxide, parachlorobenzoyl peroxide, lauroyl peroxide, and ammonium peroxide. However, the present invention is not limited to such examples. These polymerization initiators may be used alone or in combination of two or more.

  The amount of the polymerization initiator per 100 parts by mass of the monomer component A is preferably 0.01 parts by mass or more, more preferably from the viewpoint of increasing the polymerization rate and reducing the residual amount of the unreacted monomer component A. From the viewpoint of obtaining a resin emulsion for a sealer that is 0.03 parts by mass or more and forms a coating film that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance, preferably 10 parts by mass or less. More preferably, it is 5 parts by mass or less.

  The method for adding the polymerization initiator is not particularly limited. Examples of the addition method include batch charging, divided charging, and continuous dripping. Further, from the viewpoint of accelerating the completion time of the polymerization reaction, a part of the polymerization initiator may be added to the flask before or after the monomer component A is added to the reaction system.

  In order to accelerate the decomposition of the polymerization initiator, for example, a reducing agent such as sodium bisulfite and a polymerization initiator decomposition agent such as transition metal salt such as ferrous sulfate are added in an appropriate amount to the reaction system. Also good.

  Moreover, you may add additives, such as a pH buffer agent and a chelating agent, in a suitable quantity in a flask in a reaction system as needed. Since the amount of the additive varies depending on the type of the additive, it cannot be determined unconditionally, but is usually preferably 0.01 to 5 parts by mass, more preferably 0.1 to 3 parts per 100 parts by mass of monomer component A Part by mass.

  Although the atmosphere at the time of carrying out emulsion polymerization of the monomer component A is not specifically limited, It is preferable that it is inert gas, such as nitrogen gas, from a viewpoint of improving the efficiency of a polymerization initiator.

  Although the polymerization temperature at the time of carrying out emulsion polymerization of the monomer component A does not have limitation, Usually, Preferably it is 50-100 degreeC, More preferably, it is 60-95 degreeC. The polymerization temperature may be constant or may be changed during the polymerization reaction.

  The polymerization time for emulsion polymerization of the monomer component A is not particularly limited and may be appropriately set according to the progress of the polymerization reaction, but is usually about 2 to 9 hours.

  By polymerizing the monomer component A as described above, the polymer (I) forming the central layer can be obtained.

  The polymer (I) forming the central layer may have a crosslinked structure. The weight average molecular weight of the polymer (I) is preferably 100,000 from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. More preferably, it is 200,000 or more, more preferably 250,000 or more, and particularly preferably 300,000 or more. The upper limit of the weight average molecular weight of the polymer (I) is not particularly limited when it has a crosslinked structure, and it is difficult to measure the weight average molecular weight. From the viewpoint of improving the viscosity, it is preferably 5 million or less, more preferably 1 million or less, and still more preferably 700,000 or less.

  Next, after forming a central layer composed of the polymer (I), the monomer component B is emulsion-polymerized in the presence of a chain transfer agent on the central layer to thereby form the low molecular weight polymer (II). Layers other than the central layer can be formed. The low molecular weight polymer (II) is obtained by, for example, subjecting the monomer component B to emulsion polymerization in the presence of a chain transfer agent under the same polymerization method and polymerization conditions as in the case of emulsion polymerization of the monomer component A. Can be prepared.

  When the monomer component B is emulsion-polymerized, the polymerization reaction rate of the polymer (I) reaches 90% or more, preferably 95% or more, and then the monomer component B is emulsion-polymerized. This is preferable from the viewpoint of forming a layer separation structure in the particles.

  In addition, after forming the center layer made of the polymer (I) and before forming a layer other than the center layer made of the low molecular weight polymer (II), it is necessary as long as the object of the present invention is not hindered. Thus, a layer other than the central layer made of another polymer may be formed. As the monomer component used as the raw material for the other polymer, the same type of monomer as the monomer used for the monomer component can be used.

  As the monomer component used in the monomer component B, the same type of monomer as the monomer used in the monomer component can be used. These monomers may be used alone or in combination of two or more. Among these monomers, from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, Alkyl (meth) acrylates and carboxyl group-containing monomers are preferred.

  From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, the content of the styrene monomer in the monomer component B is 40 to 90% by mass, the content of the alkyl (meth) acrylate in the monomer component B is 5 to 55% by mass, and the content of the carboxyl group-containing monomer in the monomer component B is 0.5 to 20% by mass. It is preferable that

  The kind and amount of the chain transfer agent used when the monomer component B is emulsion-polymerized can be exemplified by the same kind and amount as the chain transfer agent.

  The weight average molecular weight of the low molecular weight polymer (II) forming the layers other than the central layer can be exemplified by the same weight average molecular weight as that of the low molecular weight polymer.

  A resin emulsion for a sealer containing emulsion particles having a resin layer other than the central layer formed of the polymer (I) and the low molecular weight polymer (II) as described above. Thus, a resin emulsion for sealer in which the content of styrene monomer in all monomer components used as a raw material for the resin emulsion for sealer is 40 to 90% by mass is obtained.

  The mass ratio of the polymer (I) to the low molecular weight polymer (II) [polymer (I) / low molecular weight polymer (II)] is water permeation resistance, blocking resistance, impregnation adhesion and frost resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film with excellent overall properties, preferably 10/90 or more, more preferably 20/80 or more, and even more preferably 30/70 or more, From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in blocking resistance, impregnation adhesion and frost damage resistance, it is preferably 70/30 or less, more preferably 60/40 or less.

  The polymer constituting the emulsion particles may have a crosslinked structure. The weight average molecular weight of the entire polymer is preferably 100,000 or more from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film that is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. More preferably, it is 200,000 or more, More preferably, it is 250,000 or more. The upper limit of the weight average molecular weight of the whole polymer is not particularly limited when it has a crosslinked structure, and it is difficult to measure the weight average molecular weight, but when it does not have a crosslinked structure, the film forming property is improved. From the viewpoint of making it, it is preferably 5 million or less, more preferably 1 million or less, and still more preferably 700,000 or less.

  The glass transition temperature of the entire emulsion particles is preferably 10 ° C. or higher, more preferably 20 ° C. or higher, more preferably 30 ° C. or higher, from the viewpoint of further improving the blocking resistance, and water permeability resistance, blocking resistance, impregnation. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in adhesion and frost damage resistance, it is preferably 80 ° C. or lower, more preferably 70 ° C. or lower, and even more preferably 60 ° C. or lower.

In this specification, the glass transition temperature of the polymer constituting the emulsion particles is determined by using the glass transition temperature of the monomer homopolymer used in the monomer component constituting the polymer, formula:
1 / Tg = Σ (Wm / Tgm) / 100
[Wherein Wm represents the content (% by mass) of the monomer m in the monomer component constituting the polymer, and Tgm represents the glass transition temperature (absolute temperature: K) of the homopolymer of the monomer m. ]
The temperature calculated | required based on the Formula of Fox (Fox) represented by these.

  In the present specification, the glass transition temperature of the polymer constituting the emulsion particles means the glass transition temperature determined based on the Fox (Fox) unless otherwise specified. For example, the glass transition temperature of the whole polymer constituting the emulsion particles having a plurality of resin layers corresponds to the mass fraction of each monomer in all monomer components used in the multistage emulsion polymerization. It means the glass transition temperature determined from the glass transition temperature of the homopolymer of the monomer. For monomers with unknown glass transition temperature, such as special monomers and polyfunctional monomers, the total amount of monomers with unknown glass transition temperature in the monomer component is the mass fraction. If it is 10% by mass or less, the glass transition temperature can be determined using only the monomer whose glass transition temperature is known. When the total amount of monomers with unknown glass transition temperature in the monomer component exceeds 10% by mass, the glass transition temperature of the polymer is determined by differential scanning calorimetry (DSC) or differential calorimetry. (DTA), thermomechanical analysis (TMA), etc.

  The glass transition temperature of the polymer can be easily adjusted by adjusting the composition of the monomer component. In consideration of the glass transition temperature of the polymer constituting the emulsion particles, the composition of the monomer component used as the raw material for the polymer constituting the emulsion particles can be determined.

  The glass transition temperature of the polymer is, for example, -70 ° C. for 2-ethylhexyl acrylate homopolymer, 100 ° C. for styrene homopolymer, 95 ° C. for acrylic acid homopolymer, and 130 for methacrylic acid homopolymer. ° C.

  From the viewpoint of improving the flexibility and film-forming property of the coating film, the solubility parameter (hereinafter also referred to as SP value) of the low molecular weight polymer (II) is higher than the SP value of the polymer (I). preferable. Further, the difference (absolute value) between the SP value of the polymer (I) and the low molecular weight polymer (II) is preferably large from the viewpoint of forming a layer separation structure in the emulsion particles.

  The SP value is a value defined by the regular solution theory introduced by Hildebrand, and is also a measure of the solubility of the binary solution. In general, substances having similar SP values tend to be mixed with each other. Therefore, the SP value is also a measure for judging the ease of mixing of the solute and the solvent.

  From the viewpoint of improving the mechanical stability of the emulsion particles themselves, the average particle diameter of the emulsion particles is preferably 50 nm or more, more preferably 80 nm or more, and even more preferably 100 nm or more. Water permeability resistance, blocking resistance, impregnation From the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in adhesion and frost damage resistance, it is preferably 400 nm or less, more preferably 350 nm or less, and even more preferably 300 nm or less.

  In the present specification, the average particle size of the emulsion particles is measured using a particle size distribution measuring instrument (manufactured by Particle Sizing Systems, trade name: NICOMP Model 380) by a dynamic light scattering method. It means the volume average particle diameter.

  The nonvolatile content in the resin emulsion for a sealer of the present invention is preferably 20% by mass or more, more preferably 30% by mass or more from the viewpoint of improving productivity, and preferably 70% by mass from the viewpoint of improving handleability. Hereinafter, it is 60 mass% or less more preferably.

In the present specification, the non-volatile content in the sealer resin emulsion is obtained by weighing 1 g of the sealer resin emulsion and drying it with a hot air dryer at a temperature of 110 ° C. for 1 hour.
[Non-volatile content (mass%) in resin emulsion for sealers]
= ([Residue mass] ÷ [resin emulsion for sealer 1 g]) × 100
Means the value obtained based on

  Moreover, the minimum film forming temperature of the resin emulsion for sealers of the present invention is preferably -20 to 50 ° C from the viewpoint of improving the film forming property. The minimum film-forming temperature of the resin emulsion for sealers can be adjusted, for example, by adjusting the glass transition temperature of the entire emulsion particles or the glass transition temperature of the outermost resin layer.

  In this specification, the minimum film-forming temperature of the resin emulsion for sealer is applied with an applicator so that the thickness of the resin emulsion for sealer is 0.2 mm on a glass plate placed on a thermal gradient tester. It means the temperature when a crack occurs.

  Next, (2) a resin emulsion for a sealer containing a plurality of emulsion particles having different weight average molecular weights, wherein at least one of the plurality of emulsion particles having different weight average molecular weights is composed of a low molecular weight polymer. The form which is an emulsion particle is demonstrated.

  The sealer resin emulsion having the form (2) is, for example, such that the content of the styrene monomer in all monomers used as a raw material of the sealer resin emulsion is 40 to 90% by mass. Resin emulsion containing emulsion particles composed of low molecular weight polymer (hereinafter referred to as low molecular weight resin emulsion) and resin emulsion containing emulsion particles composed of polymer having a weight average molecular weight exceeding 80,000 (hereinafter referred to as “low molecular weight resin emulsion”) And the like, but the present invention is not limited to such examples. The order of mixing these resin emulsions is arbitrary, and for example, these resin emulsions may be mixed together.

  The low molecular weight resin emulsion may have a single resin layer prepared by one-stage emulsion polymerization, or may have a plurality of resin layers prepared by multi-stage emulsion polymerization. . When the emulsion particles contained in the low molecular weight resin emulsion have a single resin layer, the emulsion particles can be prepared, for example, by emulsion polymerization of the monomer component in the presence of a chain transfer agent. . Further, when the emulsion particles have a plurality of resin layers, the emulsion particles are, for example, other than the central layer formed of the polymer (I) and the central layer formed of the low molecular weight polymer (II). Emulsion particles having a resin layer can be used. In addition, the said low molecular weight resin emulsion can be prepared by carrying out the emulsion polymerization of a monomer component with the polymerization method and polymerization conditions similar to the case where the said monomer component A or B is emulsion-polymerized.

  Further, the low molecular weight resin emulsion may contain only emulsion particles having a single resin layer, and emulsion particles having a single resin layer and emulsion particles having a plurality of resin layers are used in combination. You may do. That is, other than emulsion particles having a single resin layer formed from a low molecular weight polymer, a central layer formed from the polymer (I), and a central layer formed from a low molecular weight polymer (II) The emulsion particles having a resin layer can be used in combination.

  The high molecular weight resin emulsion may have a single resin layer prepared by one-stage emulsion polymerization or may have a plurality of resin layers prepared by multi-stage emulsion polymerization. . When the emulsion particles contained in the high molecular weight resin emulsion have a single resin layer, the emulsion particles can be prepared, for example, by emulsion polymerization of the monomer component. When the emulsion particles have a plurality of resin layers, the emulsion particles can be prepared by, for example, multistage emulsion polymerization of the monomer component. In addition, the said high molecular weight resin emulsion can be prepared by carrying out the emulsion polymerization of a monomer component with the polymerization method and polymerization conditions similar to the case where the said monomer component A or B is emulsion-polymerized.

  The mass ratio of the low molecular weight resin emulsion to the high molecular weight resin emulsion (low molecular weight resin emulsion / high molecular weight resin emulsion) is the content of the styrene monomer in all monomers used as a raw material for the resin emulsion for sealers. Is preferably determined so as to be 40 to 90% by mass, but usually a resin emulsion for a sealer that forms a coating film that is comprehensively excellent in water permeation resistance, blocking resistance, impregnation adhesion and frost resistance. Is preferably 10/90 or more, more preferably 20/80 or more, and still more preferably 30/70 or more, and is excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of obtaining a resin emulsion for a sealer that forms a coated film, it is preferably 70/30 or less, more preferably 60 40 or less.

  The sealer resin emulsion of the present invention obtained as described above may be composed only of the sealer resin emulsion, and may contain, for example, a crosslinking agent if necessary.

  Examples of the crosslinking agent include melamine crosslinking agent, oxazoline crosslinking agent, acrylamide crosslinking agent, polyamide crosslinking agent, epoxy crosslinking agent, isocyanate crosslinking agent, aziridine crosslinking agent, titanate crosslinking agent, urea crosslinking. Agents, alkyl alcoholated urea-based crosslinking agents, hydrazine compounds, carbodiimide compounds, zirconium compounds, zinc compounds, titanium compounds, aluminum compounds, and the like, but the present invention is limited to such examples only. It is not a thing. These crosslinking agents may be used alone or in combination of two or more. The amount of the crosslinking agent is preferably set as appropriate according to the type of the crosslinking agent.

  Among these crosslinking agents, an oxazoline-based crosslinking agent and a hydrazine compound are used from the viewpoint of obtaining a resin emulsion for a sealer that forms a coating film excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. Is preferred.

  Examples of the oxazoline-based crosslinking agent include 2,2′-bis (2-oxazoline), 1,2-bis (2-oxazolin-2-yl) ethane, and 1,4-bis (2-oxazolin-2-yl). ) Butane, 1,8-bis (2-oxazolin-2-yl) butane, 1,4-bis (2-oxazolin-2-yl) cyclohexane, 1,2-bis (2-oxazolin-2-yl) benzene 1,3-bis (2-oxazolin-2-yl) benzene, 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, 2 -Isopropenyl-2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline and the like. It is not limited only to hunt illustration. These oxazoline-based crosslinking agents may be used alone or in combination of two or more. The oxazoline-based crosslinking agent can be easily obtained commercially, for example, manufactured by Nippon Shokubai Co., Ltd., trade names: Epocross WS-500, Epocross WS-700, Epocross K-2010, Epocross K- 2020, Epochros K-2030, and the like, but the present invention is not limited to such examples.

  Examples of the hydrazine compound include adipic acid dihydrazide and a polymer having a dihydrazide group, but the present invention is not limited to such examples. These compounds may be used alone or in combination of two or more.

  The resin emulsion for sealers of the present invention forms a coating film that is comprehensively excellent in water permeation resistance, blocking resistance, impregnation adhesion and frost damage resistance. It can be suitably used for an undercoat paint called a sealer.

  The sealer of this invention contains the said resin emulsion for sealers, may contain only the said resin emulsion for sealers, and may contain the pigment. Examples of the pigment include organic pigments and inorganic pigments, and these pigments may be used alone or in combination of two or more.

  Examples of organic pigments include azo pigments, azomethine pigments, methine pigments, anthraquinone pigments, phthalocyanine pigments, perinone pigments, perylene pigments, diketopyrrolopyrrole pigments, thioindigo pigments, iminoisoindoline pigments, iminoisoindolinone pigments, and quinacridone red. And quinacridone pigments such as quinacridone violet, flavanthrone pigment, indanthrone pigment, anthrapyrimidine pigment, carbazole pigment, monoarylide yellow, diarylide yellow, benzoimidazolone yellow, tolyl orange, naphthol orange, quinophthalone pigment, etc. However, the present invention is not limited to such examples. These organic pigments may be used alone or in combination of two or more.

  Examples of inorganic pigments include titanium dioxide, red iron oxide, black iron oxide, iron oxide, chromium oxide green, carbon black, ferric ferrocyanide (Prussian blue), ultramarine, lead chromate, and mica. (Mica), clay, aluminum powder, pigment having a flat shape such as talc, aluminum silicate, and extender pigments such as calcium carbonate, magnesium hydroxide, aluminum hydroxide, barium sulfate, magnesium carbonate, etc. Is not limited to such examples. These inorganic pigments may be used alone or in combination of two or more.

  Among the pigments, extender pigments are preferable from the viewpoint of economy, and among them, calcium carbonate is more preferable.

  The solid content of the pigment in the total solid content of the resin emulsion for sealer and the pigment is preferably 10% by mass or more, more preferably 30% by mass or more, and further preferably 50% by mass or more, from the viewpoint of increasing the coating film hardness. From the viewpoint of improving the film forming property, it is preferably 80% by mass or less, more preferably 70% by mass or less.

  In the present invention, even if a high content of pigment is contained in the resin emulsion for sealer as described above, the film forming property is excellent and the water permeability, blocking resistance, impregnation adhesion and frost damage resistance are comprehensively improved. A sealer that forms an excellent coating film can be obtained.

In the present specification, the solid content of the pigment in the total solid content of the resin emulsion for sealer and the pigment is expressed by the formula:
[Content of Solid Content of Pigment (% by Mass) in Total Solid Content of Sealer Resin Emulsion and Pigment]
= [(Solid content of pigment) / (solid content of resin emulsion for sealer + solid content of pigment)] × 100
Means the value obtained based on

  The sealer of the present invention may contain additives as necessary. Examples of additives include aggregates, leveling agents, UV absorbers, UV stabilizers, antioxidants, polymerization inhibitors, fillers, coupling agents, rust inhibitors, antibacterial agents, metal deactivators, and wetness. Agents, antifoaming agents, surfactants, reinforcing agents, plasticizers, lubricants, antifogging agents, anticorrosive agents, pigment dispersants, flow regulators, peroxide decomposing agents, mold bleaching agents, fluorescent whitening agents, Organic flame retardants, inorganic flame retardants, anti-dripping agents, melt flow modifiers, antistatic agents, anti-algae agents, anti-mold agents, flame retardants, slip agents, metal chelating agents, anti-blocking agents, heat stabilizers , Processing stabilizers, dispersants, thickeners, rheology control agents, foaming agents, anti-aging agents, antiseptics, antistatic agents, silane coupling agents, antioxidants, film-forming aids, etc. The invention is not limited to such examples. These additives may be used alone or in combination of two or more.

  Since the amount of the additive varies depending on the type of the additive and cannot be generally determined, it is preferable to appropriately determine the amount depending on the type of the additive.

  The content of the non-volatile content in the sealer of the present invention is preferably 30% by mass or more from the viewpoint of obtaining a sealer that forms a coating film that is comprehensively excellent in water permeability resistance, blocking resistance, impregnation adhesion, and frost damage resistance. From the viewpoint of improving the handleability, it is preferably 70% by mass or less, more preferably 60% by mass or less.

  The sealer of the present invention can be easily produced, for example, by mixing the resin emulsion for the sealer, and if necessary, a pigment, an additive, water and the like. The order of mixing these components is arbitrary, and for example, these components may be mixed together.

  The sealer of the present invention obtained as described above is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance, and can be suitably used for, for example, inorganic building materials. .

  In general, inorganic building materials often have a water absorption property, and water is easily permeable to the inside, so that it easily deteriorates. Is applied. Moreover, the top coating material is normally apply | coated to the surface of an inorganic building material in order to provide a desired design. Among these, the sealer of the present invention can be suitably used as a primer.

  Examples of the inorganic building material include a ceramic base material and a metal base material. Ceramic base materials are used for applications such as tiles and outer wall materials, for example. Ceramic base material is the addition of inorganic fillers, fibrous materials, etc. to the hydraulic glue used as the raw material for inorganic cured bodies, molding the resulting mixture, curing the resulting molded body and curing it. Obtained by. Examples of inorganic building materials include flexible boards, calcium silicate boards, gypsum slag perlite boards, wood chip cement boards, precast concrete boards, ALC boards, and gypsum boards.

  Examples of methods for applying the sealer of the present invention to inorganic building materials include spray coating, roll coating, brush coating, trowel coating, bar coating, die coating, comma coating, gravure coating, kiss coating, Examples of the spin coating method, dip coating method, curtain coating method, doctor blade coating method, knife coating method, air knife coating method, micro gravure coating method, offset gravure coating method, lip coating method, etc. It is not limited only to such illustration. Among these methods, the sealer of the present invention can be suitably used for the roll coating method.

  The sealer of the present invention may be applied alone as a single layer, or may be applied by recoating two or more layers. When coating is performed by recoating two or more layers, only a part of the layers may be formed by the sealer of the present invention, or all the layers may be formed by the sealer of the present invention.

The amount of the sealer applied on the surface of the inorganic building material cannot be determined unconditionally because it varies depending on the type of the inorganic building material, etc., but the water permeability, blocking resistance, impregnation adhesion and frost damage resistance From the viewpoint of forming a comprehensively excellent coating film, it is usually preferable that the nonvolatile content is about 10 to 500 g / m ² .

  The coating film made of the sealer of the present invention formed on the surface of the inorganic building material may be dried at room temperature, for example, or may be dried by heating.

  In addition, the thickness of the coating film comprising the sealer of the present invention formed on the surface of the inorganic building material after drying is excellent in water permeability, blocking resistance, impregnation adhesion and frost damage resistance. In general, the thickness is preferably about 0.5 to 600 μm, more preferably about 1 to 500 μm.

  By applying the sealer to the inorganic building material as described above, an inorganic building material to which the sealer is applied can be obtained.

  EXAMPLES Next, although this invention is demonstrated further in detail based on an Example, this invention is not limited only to this Example. In the following, “part” means “part by mass” unless otherwise specified.

Production Example 404.9 parts of deionized water, 20 parts of a dispersant [trade name: Demol EP, manufactured by Kao Corporation], 16 parts of a dispersant [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: DISCOAT N-14] 16 .7 parts, defoaming agent [manufactured by San Nopco, trade name: Nopco 8034L], calcium carbonate [heavy calcium carbonate, manufactured by Maruo Calcium Co., Ltd., R heavy coal, average particle size: 7. 4 μm] 1000 parts and a thickening agent (trade name: Acryset WR-503A, manufactured by Nippon Shokubai Co., Ltd.) 6 parts were mixed with stirring with a disper and then aged by stirring at 1000 min ^{−1 for} 30 minutes. Then, the mixture was filtered through a 100 mesh (JIS mesh, hereinafter the same) wire mesh to obtain a calcium carbonate paste having a nonvolatile content of 70% by mass. The nonvolatile content in the calcium carbonate paste was determined by the same method as the nonvolatile content in the resin emulsion.

Example 1
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  A pre-emulsion for dripping consisting of 100 parts of deionized water, 40 parts of 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10] and 340 parts of styrene was prepared in a dropping funnel.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Thereafter, from 100 parts of deionized water, 40 parts of a 25% aqueous solution of an emulsifier [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 100 parts of 2-ethylhexyl acrylate, 225 parts of styrene and 5 parts of acrylic acid. The second stage pre-emulsion, 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogen sulfite aqueous solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 100 parts of deionized water, 40 parts of a 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 97 parts of 2-ethylhexyl acrylate, 190 parts of styrene, 40 parts of methacrylic acid A third pre-emulsion consisting of 3 parts of octyl thioglycolate, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were added dropwise to the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added, and pH (measured at 23 ° C. using Horiba, Ltd., product number: F-23, the same shall apply hereinafter) was adjusted to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100-mesh wire mesh to obtain a resin emulsion for a sealer having a nonvolatile content of 43.0% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above have a three-layer structure, the glass transition temperature of the emulsion particles as a whole is 49 ° C., and the weight average molecular weight of the entire polymer constituting the emulsion particles is It was 300,000. The weight average molecular weight of the polymer constituting the outermost resin layer of the emulsion particles is 45,000, and the weight average molecular weight of all polymers contained in the resin emulsion for sealers is 45,000. The coal content was 35 area%. The styrene content in all monomers used as a raw material for the resin emulsion for sealer was 75.5% by mass.

Example 2
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  A pre-emulsion for dropping comprising 59 parts of deionized water, 24 parts of a 25% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10] and 200 parts of styrene was prepared in a dropping funnel.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Thereafter, from 152 parts of deionized water, 60 parts of a 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 240 parts of 2-ethylhexyl acrylate, 250 parts of styrene and 10 parts of acrylic acid. The second stage pre-emulsion, 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogen sulfite aqueous solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 91 parts of deionized water, 36 parts of 25% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 82 parts of 2-ethylhexyl acrylate, 180 parts of styrene, 35 parts of acrylic acid A third pre-emulsion consisting of 3 parts of octyl thioglycolate, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were added dropwise to the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added to adjust the pH to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100 mesh wire netting to obtain a resin emulsion for a sealer having a nonvolatile content of 42.9% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above have a three-layer structure, the glass transition temperature of the whole emulsion particles is 21 ° C., and the weight average molecular weight of the whole polymer constituting the emulsion particles is It was 310,000. The polymer constituting the outermost resin layer of the emulsion particles has a weight average molecular weight of 43,000, and the weight average molecular weight of all the polymers contained in the resin emulsion for sealers is 43,000. The coal content was 34 area%. The styrene content in all monomers used as a raw material for the resin emulsion for the sealer was 63.0% by mass.

Example 3
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  In a dropping funnel, a pre-emulsion for dropping consisting of 90 parts of deionized water, 50 parts of a 20% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Hytenol NF-08] and 340 parts of styrene was prepared.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Then, 90 parts of deionized water, 50 parts of a 20% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Hytenol NF-08], 100 parts of 2-ethylhexyl acrylate, 225 parts of styrene and 5 parts of acrylic acid A second pre-emulsion consisting of 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogensulfite aqueous solution was dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 90 parts of deionized water, 50 parts of a 20% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Hytenol NF-08], 97 parts of 2-ethylhexyl acrylate, 190 parts of styrene, 40 parts of methacrylic acid A third pre-emulsion consisting of 3 parts of octyl thioglycolate, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were added dropwise to the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added to adjust the pH to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100 mesh wire netting to obtain a resin emulsion for a sealer having a nonvolatile content of 42.9% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above have a three-layer structure, the glass transition temperature of the emulsion particles as a whole is 49 ° C., and the weight average molecular weight of the entire polymer constituting the emulsion particles is It was 290,000. The weight average molecular weight of the polymer constituting the outermost resin layer of the emulsion particles is 46,000, and the weight average molecular weight of all the polymers contained in the resin emulsion for sealers is 46,000. The content rate of coalescence was 36 area%. The styrene content in all monomers used as a raw material for the resin emulsion for sealer was 75.5% by mass.

Example 4
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  A pre-emulsion for dripping consisting of 100 parts of deionized water, 40 parts of 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10] and 340 parts of styrene was prepared in a dropping funnel.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Thereafter, from 100 parts of deionized water, 40 parts of 25% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 117 parts of 2-ethylhexyl acrylate, 208 parts of styrene and 5 parts of acrylic acid. The second stage pre-emulsion, 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogen sulfite aqueous solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 100 parts of deionized water, 40 parts of 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 114 parts of 2-ethylhexyl acrylate, 173 parts of styrene, 40 parts of methacrylic acid A third pre-emulsion consisting of 3 parts of octyl thioglycolate, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were added dropwise to the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added to adjust the pH to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100-mesh wire mesh to obtain a resin emulsion for a sealer having a nonvolatile content of 43.0% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above have a three-layer structure, the glass transition temperature of the whole emulsion particles is 40 ° C., and the weight average molecular weight of the whole polymer constituting the emulsion particles is It was 320,000. The weight average molecular weight of the polymer constituting the outermost resin layer of the emulsion particles is 45,000, and the weight average molecular weight of all polymers contained in the resin emulsion for sealers is 45,000. The coal content was 32 area%. Moreover, the content rate of styrene in all the monomers used as a raw material of the resin emulsion for the sealer was 72.1% by mass.

Comparative Example 1
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  A pre-emulsion for dripping consisting of 100 parts of deionized water, 40 parts of 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10] and 340 parts of styrene was prepared in a dropping funnel.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Thereafter, from 100 parts of deionized water, 40 parts of a 25% aqueous solution of an emulsifier [manufactured by Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 100 parts of 2-ethylhexyl acrylate, 225 parts of styrene and 5 parts of acrylic acid. The second stage pre-emulsion, 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogen sulfite aqueous solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 100 parts of deionized water, 40 parts of a 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 100 parts of 2-ethylhexyl acrylate, 190 parts of styrene and 40 parts of methacrylic acid A 3rd stage pre-emulsion consisting of 29 parts of a 3.5% aqueous solution of ammonium persulfate and 20 parts of a 2.5% aqueous solution of sodium hydrogen sulfite was dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added to adjust the pH to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100-mesh wire mesh to obtain a resin emulsion for a sealer having a nonvolatile content of 43.0% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above had a three-layer structure, and the glass transition temperature of the emulsion particles as a whole was 49 ° C. Moreover, since the weight average molecular weight of the whole polymer which comprises the said emulsion particle, and the weight average molecular weight of the polymer which comprises the resin layer of each layer of the said emulsion particle exceeded the measurement limit (5 million), it can measure. could not. The styrene content in all monomers used as a raw material for the resin emulsion for sealer was 75.5% by mass.

Comparative Example 2
In a flask equipped with a dropping funnel, a stirrer, a nitrogen gas inlet tube, a thermometer and a reflux condenser, 800 parts of deionized water was charged.

  A pre-emulsion for dropping comprising 59 parts of deionized water, 24 parts of a 25% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10] and 200 parts of styrene was prepared in a dropping funnel.

  Of the obtained pre-emulsion for dripping, 71 parts corresponding to 5% of the total amount of the monomer components were added to the flask, the temperature was raised to 80 ° C. while gently blowing nitrogen gas, and 3.5% ammonium persulfate was added. 14 parts of the aqueous solution was added into the flask, and emulsion polymerization was started.

  Next, the remainder of the dropping pre-emulsion, 29 parts of a 3.5% aqueous ammonium persulfate solution and 20 parts of a 2.5% aqueous sodium hydrogen sulfite solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Thereafter, from 152 parts of deionized water, 60 parts of a 25% aqueous solution of emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 240 parts of 2-ethylhexyl acrylate, 250 parts of styrene and 10 parts of acrylic acid. The second stage pre-emulsion, 29 parts of a 3.5% ammonium persulfate aqueous solution and 20 parts of a 2.5% sodium hydrogen sulfite aqueous solution were dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 60 minutes.

  Next, 91 parts of deionized water, 36 parts of a 25% aqueous solution of an emulsifier [Daiichi Kogyo Seiyaku Co., Ltd., trade name: Aqualon HS-10], 85 parts of 2-ethylhexyl acrylate, 180 parts of styrene and 35 parts of acrylic acid A 3rd stage pre-emulsion consisting of 29 parts of a 3.5% aqueous solution of ammonium persulfate and 20 parts of a 2.5% aqueous solution of sodium hydrogen sulfite was dropped into the flask over 90 minutes. After completion of dropping, the temperature was maintained at 80 ° C. for 120 minutes.

  Thereafter, 25% aqueous ammonia was added to adjust the pH to 8 to complete the emulsion polymerization reaction. The obtained reaction mixture was cooled to room temperature and then filtered through a 100-mesh wire mesh to obtain a resin emulsion for a sealer having a nonvolatile content of 43.0% by mass.

  The emulsion particles contained in the resin emulsion for sealers obtained above had a three-layer structure, and the glass transition temperature of the whole emulsion particles was 21 ° C. Moreover, since the weight average molecular weight of the whole polymer which comprises the said emulsion particle, and the weight average molecular weight of the polymer which comprises the resin layer of each layer of the said emulsion particle exceeded the measurement limit (5 million), it can measure. could not. The styrene content in all monomers used as a raw material for the resin emulsion for the sealer was 63.0% by mass.

Experimental Example 100 parts of the resin emulsion for sealers obtained in Example 1, Example 3, Example 4 and Comparative Example 1 were dispersed with a homodisper at 1000 min ⁻¹ while using 2,2,4- as a film-forming aid. 9.5 parts of trimethyl-1,3-pentanediol monoisobutyrate [manufactured by JNC, product number: CS-12] was added to the resin emulsion for sealer to obtain a mixture.

While dispersing 100 parts of the resin emulsion for sealers obtained in Example 2 and Comparative Example 2 with a homodisper at 1000 min ⁻¹ , 2,2,4-trimethyl-1,3-pentanediol monoiso is used as a film-forming aid. 3 parts of butyrate [manufactured by JNC Co., Ltd., product number: CS-12] was added to the resin emulsion for sealer to obtain a mixture.

The calcium carbonate obtained in the production example so that the solid content of the calcium carbonate paste in the total solid content of the resin emulsion for sealer and the calcium carbonate paste obtained in each Example and each Comparative Example was 60% by mass. The paste was added to the mixture obtained above, and an appropriate amount of dilution water and an appropriate amount of silicone-based antifoaming agent (manufactured by San Nopco Co., Ltd., trade name: SN deformer 777) were added so that the nonvolatile content was 50% by mass. after addition to the mixture, BM type viscometer [Tokyo Keiki Co., Ltd.] in a thickener so that the viscosity at 25 ° C. in the rotation speed 30min ^-1 is 2000 mPa · s [KK ADEKA, trade Name: Adecanol UH-420] was added to the mixture and stirred at a rotational speed of 1000 min ^-1 for 15 minutes to obtain a sealer. The sealer was allowed to stand for more than 1 day at room temperature.

Next, the sealer obtained above was applied to a flexible board (manufactured by Nippon Test Panel Co., Ltd., length: 70 mm, width: 150 mm, thickness: 10 mm) with a sponge roll coater in an amount of 90 g / m ² , and hot air The test plate was obtained by making it dry at 100 degreeC with a dryer for 10 minutes. Using the obtained test plate, water permeability resistance, blocking resistance, impregnation adhesion and frost damage resistance were examined as physical properties of the resin emulsion for sealers based on the following methods. The results are shown in Table 1.

<Water resistance>
A funnel (diameter: 10 cm) is placed on the coating film formed on the test plate, and the contact portion of both is sealed with a silicone bath bond (manufactured by Konishi Co., Ltd.), and the “funnel method” prescribed in JIS K5400 is used. Based on the following evaluation criteria, the water loss after 24 hours was measured based on the following evaluation criteria.
(Evaluation criteria)
25 points: less than 0.020 mL / cm ² 10 points: 0.020 mL / cm ² or more, less than 0.025 mL / cm ² 0 points: 0.025 mL / cm ² or more

<Blocking resistance>
After two test plates (7 × 15 cm) were allowed to stand in an atmosphere of 60 ° C. for 1 hour, the surfaces on which the coating films of the test pieces were formed were overlapped, and a load of 300 g / cm ² was placed thereon. In this state, the test plate was allowed to stand at a temperature of 60 ° C. for 24 hours, and then each test plate was separated, the state of the coating film surface was visually observed, and evaluated based on the following evaluation criteria.
(Evaluation criteria)
25 points: There is no resistance when peeling the coating films 10 points: There is resistance when peeling the coating films, but there is no peeling of the coating film after peeling 0 points: The coating films are peeled off When there is resistance, there is peeling of the coating film after peeling

<Impregnation adhesion>
The test plate was immersed in warm water kept at a temperature of 50 ° C. for 24 hours, then removed from the warm water, sufficiently wiped off moisture, and further dried in the atmosphere at 23 ° C. for 24 hours. Thereafter, the coating film of the test plate was cut with a cutter knife so that 100 squares of 2 mm square were formed, and cellophane adhesive tape [manufactured by Nichiban Co., Ltd., product number: CT405AP-18] was applied to this grid. In addition, a peel test was performed in accordance with JIS K5400, and the number of remaining grids was counted and evaluated based on the following evaluation criteria.
(Evaluation criteria)
25 points: 95 or more remaining grids 10 points: 80 to 94 remaining grids 0 points: 79 or less remaining grids

<Frost resistance>
After sealing the side surface of the test plate and the back surface on which the coating film is not formed with a silicone-based bath bond (manufactured by Konishi Co., Ltd.), it is frozen for 2 hours by cooling to −20 ° C. in the air using a freeze-thaw tester. Then, the operation of immersing in water at 20 ° C. for 2 hours is one cycle, and the operation is performed 600 cycles while observing the occurrence of cracks on the coating film surface using a magnifying glass with a magnification of 30 times every 100 cycles. Evaluation was made based on the following evaluation criteria.
(Evaluation criteria)
25 points: No problem even at 600 cycles 10 points: No problem at 400 cycles, but cracks occurred at 600 cycles 0 points: Cracks occurred at 400 cycles

〔Comprehensive evaluation〕
Total evaluation (100 points maximum) was performed by summing up the evaluation scores in each test item. In addition, the resin emulsion for sealers which has at least one evaluation of 0 points in the physical property evaluation fails.

  From the results shown in Table 1, all of the resin emulsions for sealers obtained in each example form a coating film that is comprehensively excellent in water permeability, blocking resistance, impregnation adhesion, and frost damage resistance. I understand that

  The resin emulsion for sealers of the present invention forms a coating film that is comprehensively excellent in water permeation resistance, blocking resistance, impregnation adhesion, and frost damage resistance. For example, the surface of an inorganic building material such as a ceramic base material Or, it is useful for undercoat materials called sealers that are applied to the back surface, and can be suitably used for undercoat paints used in factory coating, that is, when coating inorganic building materials on the line in the factory. .

Claims (4)

  A sealer resin emulsion containing a polymer having a weight average molecular weight of 10,000 to 80,000, wherein the content of styrene monomer in all monomer components used as a raw material of the sealer resin emulsion is 40 to 90 A resin emulsion for a sealer, characterized in that the content is% by mass.   A sealer comprising the resin emulsion for a sealer according to claim 1.   An inorganic building material having a coating film comprising the sealer according to claim 2.   A method for producing a sealer resin emulsion containing a polymer having a weight average molecular weight of 10,000 to 80,000, wherein the sealer resin emulsion contains a polymer having a weight average molecular weight of 10,000 to 80,000, The manufacturing method of the resin emulsion for sealers characterized by adjusting the content rate of the styrene-type monomer in all the monomer components used as a raw material of the said resin emulsion for sealers to 40-90 mass%.