Aqueous stripping composition

Abstract

To provide an aqueous remover composition that is environmentally friendly, has a superior removal effect, has excellent nonflammability, and exhibits long-lasting nonflammability.SOLUTION: The inventive remover composition contains (A) water and (B) an aromatic alcohol blended with a specific amount of (C) solid paraffin.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention provides an aqueous stripping composition that has a small environmental impact, has excellent stripping effect, is non-flammable, and has excellent durability of non-flammability after application. [Background technology]

[0002] Methods for repainting a paint film (old paint film) formed on the surface of a building, civil engineering structure, etc. include painting a new paint over the old paint film, or peeling off the old paint film and painting a new paint film. Conventionally, repainting has often been done by painting a new paint over the old paint film in terms of cost and shortening construction time, and there are currently many buildings and civil engineering structures that have had two or three or more coats of paint applied over the old paint film.

[0003] However, if new paint is applied multiple times on top of an already deteriorated old paint film, the paint film itself may become heavy and put a strain on the substrate. The paint film itself may also become too thick and compress the space. Furthermore, with the emergence of high-performance paint films in recent years, it may be difficult to apply new paint on top of a paint film.

[0004] Due to these problems, recently, methods of first peeling off the old paint film have become more common. Methods for removing old paint films include physical methods such as sanding, blasting, high-pressure water spraying, and chiseling, as well as chemical methods using chemicals and solvents.However, recently, chemical methods using water-based stripping agents have come to be used due to issues such as damage to the base and dust dispersion, as well as environmental considerations and safety. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2020-84164 [Patent Document 2] WO2018 / 179925 Summary of the Invention [Problem to be solved by the invention]

[0006] For example, Patent Documents 1 and 2 describe aqueous stripping agents whose basic composition is water and aromatic alcohol (benzyl alcohol), and state that they have a small environmental impact and stripping effect. However, aqueous stripping agents are usually applied between 1 and 48 hours after application, when the old paint film has softened before the stripping process begins. However, there is a risk of the agent catching fire some time after application, and this risk could be expected in some cases, for example, with paint films that are being stripped or that have already been stripped. [Means for solving the problem]

[0007] The present invention has been made in view of these problems, and it has been discovered that by mixing a specific amount of (C) solid paraffin with (A) water, (B) an aromatic alcohol, an aqueous stripping agent composition can be obtained that has a low environmental impact, has excellent stripping effect, is non-flammable, and has excellent durability of non-flammability after application, which has led to the completion of the present invention.

[0008] That is, the present invention has the following features. 1. (A) Water, and (B) aromatic alcohols, An aqueous stripper composition comprising: Furthermore, (C) solid paraffin 0.01% by weight or more and 10% by weight or less, (D) an aromatic organic solvent having 6 to 15 carbon atoms, and an aliphatic solvent having 6 to 30 carbon atoms; 1. An aqueous stripping composition comprising: 2.(A) Water 20% by weight or more and 60% by weight or less, (B) 40% by weight or more and 80% by weight or less of aromatic alcohol; (C) solid paraffin 0.01% by weight or more and 10% by weight or less, (D) 0.1% by weight or more and 10% by weight or less of an aromatic organic solvent having 6 to 15 carbon atoms, and 0.5% by weight or more and 10% by weight or less of an aliphatic solvent having 6 to 30 carbon atoms, 1. An aqueous stripping composition comprising: 3 1. Furthermore, it is characterized in that it contains (E) a surfactant. or 2 . An aqueous stripper composition according to claim 1. 4 1. to 1., further characterized in that it contains (F) a volatilization inhibitor. 3 . An aqueous stripping composition described in any one of the above. [Effects of the Invention]

[0009] The aqueous stripping composition of the present invention has a small environmental impact, has an excellent stripping effect, and is non-flammable and has excellent durability of non-flammability after application. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described.

[0011] The aqueous stripping composition of the present invention is characterized by being a mixture of (A) water (hereinafter also referred to as "component (A)"), (B) aromatic alcohol (hereinafter also referred to as "component (B)"), and (C) solid paraffin (hereinafter also referred to as "component (C)") in an amount of 0.01 wt % to 10 wt %.

[0012] Examples of the component (B) used in the present invention include benzyl alcohol, phenylethyl alcohol, naphthol, etc. In the present invention, it is particularly preferable to use benzyl alcohol. By mixing such components (B) and (A), it is possible to obtain an aqueous stripping agent that has excellent stripping effect, is non-flammable, and has excellent durability of non-flammability after application.

[0013] The component (C) used in the present invention is solid paraffin having a melting point of 30° C. or higher and 70° C. or lower (preferably 35° C. or higher and 65° C. or lower). By mixing such component (C) in an amount of 0.01% by weight or more and 10% by weight or less (preferably 0.03% by weight or more and 8% by weight or less, and even more preferably 0.05% by weight or more and 5% by weight or less) relative to the total amount of the composition, it is possible to impart non-flammability over time after application, and to obtain excellent sustained non-flammability.

[0014] The blending amounts of the (A) component and the (B) component are preferably 20% by weight or more and 60% by weight or less (preferably 25% by weight or more and 55% by weight or less, more preferably 30% by weight or more and 50% by weight or less) of the (A) component and 40% by weight or more and 80% by weight or less (preferably 45% by weight or more and 75% by weight or less, more preferably 50% by weight or more and 70% by weight or less) of the (B) component, relative to the total amount of the composition. By using the composition in this range, it is possible to obtain a release agent that has a small environmental impact, is excellent in release effect, and is non-flammable.

[0015] In addition to the above components (A), (B), and (C), the aqueous release agent of the present invention may contain (D) an aromatic solvent (hereinafter also referred to as "component (D)"), (E) a surfactant (hereinafter also referred to as "component (E)"), and (F) a volatilization inhibitor (hereinafter also referred to as "component (F)").

[0016] Examples of component (D) used in the present invention include toluene, xylene, benzene, ethylbenzene, ethyltoluene, cumene, cymene, trimethylbenzene, naphthalene, chlorobenzene, dichlorobenzene, benzyl phenyl ether, benzyl methyl ether, methyl phenyl ether, ethyl phenyl ether, propyl phenyl ether, butyl phenyl ether, 1,2-methylenedioxybenzene, 1,2-ethylenedioxybenzene, dibenzyl ether, and diphenyl ether. One or more of these can be used. In the present invention, aromatic solvents (preferably aromatic hydrocarbon solvents) having 6 to 15 carbon atoms (preferably 7 to 12 carbon atoms), particularly one or more selected from toluene, xylene, benzene, ethylbenzene, ethyltoluene, cumene, cymene, and trimethylbenzene, are preferably used. Chlorinated aromatic solvents such as chlorobenzene and dichlorobenzene are preferably not included or are present in an amount of 10 wt.% or less of the total amount of component (D) in terms of reducing environmental impact and odor. Furthermore, from the viewpoints of reducing the environmental load and reducing odor, aromatic ether solvents such as benzyl phenyl ether, benzyl methyl ether, methyl phenyl ether, ethyl phenyl ether, propyl phenyl ether, butyl phenyl ether, 1,2-methylenedioxybenzene, 1,2-ethylenedioxybenzene, dibenzyl ether, and diphenyl ether are preferably not contained or are contained in an amount of 90% by weight or less (more preferably 50% by weight or less, and even more preferably 10% by weight or less) of the total amount of component (D). Component (D) is expected to have a particularly improved release effect. Component (D) is also highly compatible with components (B) and (C), and the synergistic effects of components (B) and (C) with component (D) can provide even better release effect and sustained non-flammability. The amount of component (D) to be blended is not particularly limited, but is preferably 0.1% by weight or more and 10% by weight or less (preferably 0.3% by weight or more and 8% by weight or less, and more preferably 0.5% by weight or more and 5% by weight or less) of the total amount of the composition.

[0017] The component (E) used in the present invention is not particularly limited to anionic surfactants, cationic surfactants, nonionic surfactants, etc. In the present invention, examples thereof include polyoxyalkylene alkyl ethers having an alkyl group and an oxyalkylene unit, or their sulfates, sulfate ester salts, sulfonates, sulfonate ester salts, succinates, succinate ester salts, etc., and it is preferable to use one or more of these. Specific examples of polyoxyalkylene alkyl ethers include polyoxyethylene nonylphenyl ether, polyoxyethylene octylphenyl ether, polyoxyethylene distearate, polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, polyoxyethylene alkyl ether, polyoxyethylene phenyl ether, polyoxyethylene tridecyl ether, polyoxyethylene decyl ether, polyoxyethylene octyldodecyl ether, etc. Examples of oxyalkylene units include oxyethylene units and oxypropylene units, and the number of repeating units is preferably 6 to 50, and more preferably 8 to 30. The alkyl group preferably has 6 to 30 carbon atoms (preferably 8 to 24 carbon atoms). Component (E) forms an emulsified dispersion of components (A) and (B) and can enhance dispersion stability. Furthermore, by mixing it with component (D), a release agent with excellent release effect and long-lasting release effect can be obtained. The amount of component (E) to be blended is not particularly limited, but is preferably 0.1% by weight or more and 10% by weight or less (preferably 0.5% by weight or more and 8% by weight or less, and more preferably 1.0% by weight or more and 6% by weight or less) of the total amount of the composition.

[0018] Examples of the component (F) used in the present invention include trihydric alcohols such as glycerin, butanetriol, 2-methyl-propanetriol, pentanetriol, 2-methyl-butanetriol, trimethylolethane, hexanetriol, 2-ethyl-butanetriol, and trimethylolpropane; tetrahydric alcohols such as pentaerythritol, pentanetetrol, hexanetetrol, diglycerin, and ditrimethylolpropane; pentahydric alcohols such as adonitol, arabitol, xylitol, and triglycerin; hexahydric alcohols such as dipentaerythritol, sorbitol, mannitol, iditol, inositol, dulcitol, talose, and allose; Examples of suitable alcohols include octahydric alcohols such as tripentaerythritol, amines such as triethanolamine and triisopropanolamine, benzenetricarboxylic acids such as trimellitic acid and hemimellitic acid, benzenetetracarboxylic acids such as pyromellitic acid, benzenehexacarboxylic acids such as mellitic acid, cyclohexanetricarboxylic acid, triaminotriethylamine, triethylenetetramine, and hexamethylphosphoric triamide, and one or more of these may be used. In the present invention, it is particularly preferred to use one or more trihydric alcohols, and it is even more preferred to use glycerin. Such component (F) prevents the evaporation of components (A) and (B), and can improve the durability of the peeling effect and the durability of non-flammability after application. The amount of component (F) to be blended is not particularly limited, but is preferably 0.1% by weight or more and 20% by weight or less (preferably 0.5% by weight or more and 18% by weight or less, and more preferably 1% by weight or more and 15% by weight or less) of the total amount of the composition.

[0019] In addition to the above components, the aqueous stripping agent of the present invention may contain, for example, an aliphatic solvent, a thickener, an oxidizing agent, a reducing agent, a resin, a wax, a fragrance, a colorant, a dye, and the like.

[0020] As the aliphatic solvent, for example, an aliphatic solvent having 6 to 30 carbon atoms (preferably 8 to 24 carbon atoms, more preferably 10 to 22 carbon atoms, and even more preferably 12 to 20 carbon atoms) can be used, and this component is expected to improve the durability of the peeling effect. Examples of the aliphatic solvent include those exemplified below, and one or more of these can be used as needed. Linear, branched, saturated, or unsaturated aliphatic hydrocarbons with 6 to 30 carbon atoms Examples thereof include hexane, octane, nonane, decane, undecane, dodecane, tridecane, pentadecane, tetradecane, hexadecane, heptadecane, octadecane, nonadecane, eicosane, docosane, tricosane, tetracosane, pentacosane, hexacosane, heptacosane, octacosane, nonacosane, and triacontane. Linear, branched, saturated, or unsaturated aliphatic monoalcohols with 6 to 30 carbon atoms Examples of alcohols that can be used include, but are not limited to, primary, secondary, and tertiary alcohols, such as hexanol, heptanol, octanol, nonanol, decanol, undecanol, dodecanol, tridecanol, tetradecanol, pentadecanol, hexadecanol, heptadecanol, octadecanol, nonadecanol, eicosanol, heneicosanol, docosanol, tricosanol, tetracosanol, pentacosanol, hexacosanol, heptacosanol, octacosanol, nonacosanol, triacontanol, oleyl alcohol, linoleyl alcohol, and palmitoleyl alcohol. , Elaidyl alcohol, Elaidlinoleyl alcohol, Linolenyl alcohol, Elaidlinolenyl alcohol, Erucyl alcohol, Isohexanol, 2-Methyl-1-pentanol, 3-Methyl-1-pentanol, 2-Ethyl-1-butanol, 3,3-Dimethyl-1-butanol, Isoheptanol, 4-Methyl-1-hexanol, 3-Methyl-1-hexanol, 2-Ethyl-2-methyl-1-butanol, Isooctanol, 2-Ethylhexanol, 6-Methyl-2-heptanol, Isononanol, 3,5,5-Trimethylhexanol, Isodecanol, Isoundecanol, Isododecanol, 2-Butyloctanol Examples of the isopropyl alcohol include ethanol, isotridecanol, isotetradecanol, isopentadecanol, 2-hexyldecanol, isohexadecanol, 2-hexyldecanol, isoheptadecanol, isooctadecanol, 2-isoheptylisoundecanol, isononadecanol, isoeicosanol, 2-octyldodecanol, isoheneicosanol, 18-methyleicosanol, isodocosanol, isotricosanol, isotetracosanol, 2-decyltetradecanol, isopentacosanol, isohexacosanol, isoheptacosanol, isooctacosanol, isononacosanol, and isotriacontanol. Linear or branched saturated or unsaturated aliphatic dialcohols with 6 to 30 carbon atoms Examples thereof include hexanediol, heptanediol, octanediol, nonanediol, decanediol, undecanediol, dodecanediol, tridecanediol, tetradecanediol, pentadecanediol, hexadecanediol, heptadecanediol, octadecanediol, nonadecanediol, eicosanediol, heneicosanediol, docosanediol, tricosanediol, tetracosanediol, pentacosanediol, hexacosanediol, heptacosanediol, octacosanediol, nonacosanediol, triacosanediol, and ricinoleyl alcohol. Linear, branched, saturated, or unsaturated aliphatic monocarboxylic acids with 6 to 30 carbon atoms For example, hexanoic acid, heptanoic acid, octanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tridecanoic acid, tetradecanoic acid, pentadecanoic acid, hexadecanoic acid, and heptadecanoic acid , Octadecanoic acid, Nonadecanoic acid, Eicosanoic acid, Heneicosanoic acid, Docosanoic acid, Tricosanoic acid, Tetracosanoic acid, Pentacosanoic acid, Hexacosanoic acid, Heptacosanoic acid, Octacosanoic acid, Nonacosanoic acid, Triacontanoic acid, Sapienic acid, Oleic acid, Eicosenoic acid, Erucic acid, Nervonic acid, Palmitoleic acid, Vaccenic acid, Paulic acid, Mead acid, Linoleic acid, γ-linolenic acid, Pinolenic acid, Eicosadienoic acid, Dihomo-γ-linolenic acid, Arachidonic acid, Docosadienoic acid, Docosatetraenoic acid, Adrenic acid, Docosapentaenoic acid, Osbondoic acid, α-linolenic acid, Stearidonic acid, Eicosatrienoic acid , eicosatetraenoic acid, eicosapentaenoic acid, docosapentaenoic acid, docosahexaenoic acid, tetracosapentaenoic acid, tetracosahexaenoic acid, ricinoleic acid, myristoleic acid, pentadecenoic acid, heptadecenoic acid, petroselinic acid, eleostearic acid, bosseopentaenoic acid, gadoleic acid, ethylhexanoic acid, neodecanoic acid, isotridecanoic acid, isotetradecanoic acid, isopentadecanoic acid, isohexadecanoic acid, 2-hexyldecanoic acid, isoheptadecanoic acid, isooctadecanoic acid, isononadecanoic acid, isoeicosanoic acid, 2-octyldodecanoic acid, 2-decyltetradecanoic acid, and the like. Linear or branched saturated or unsaturated aliphatic dicarboxylic acids with 6 to 30 carbon atoms For example, hexanedioic acid, heptanedioic acid, octanedioic acid, nonanedioic acid, decanedioic acid, and the like can be mentioned. Linear, branched, saturated, or unsaturated aliphatic monoesters with 6 to 30 carbon atoms Examples include aliphatic monoesters which are reaction products of the above-mentioned aliphatic monocarboxylic acids having from 6 to 30 carbon atoms and alcohols, and aliphatic monoesters which are reaction products of the above-mentioned aliphatic monoalcohols having from 6 to 30 carbon atoms and carboxylic acids. Linear, branched, saturated, or unsaturated aliphatic diesters with 6 to 30 carbon atoms Examples include aliphatic diesters which are reaction products of the above-mentioned aliphatic dicarboxylic acids having 6 to 30 carbon atoms and alcohols, and aliphatic diesters which are reaction products of the above-mentioned aliphatic dialcohols having 6 to 30 carbon atoms and carboxylic acids. The alcohol used in producing the aliphatic monoesters and aliphatic diesters may be one or more selected from the aliphatic monoalcohols listed above, or methanol, ethanol, propanol, butanol, and pentanol. The carboxylic acid may be one or more selected from the aliphatic monocarboxylic acids listed above, or methanoic acid, ethanoic acid, propanoic acid, butanoic acid, and pentanoic acid. Linear, branched, saturated, or unsaturated aliphatic ethers with 6 to 30 carbon atoms For example, heptyl ether, octyl ether, tetradecyl ether, hexadecyl ether, etc. may be mentioned. Linear, branched, saturated, or unsaturated aliphatic ketones with 6 to 30 carbon atoms Examples include methyl isobutyl ketone, diisobutyl ketone, heptanone, cyclohexanone, cycloheptanone, cyclooctanone, and isophorone. Linear, branched, saturated, or unsaturated aliphatic monoamines with 6 to 30 carbon atoms Examples thereof include hexylamine, heptylamine, octylamine, ethylhexylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, icosylamine, docosylamine, tetracosylamine, pentacosylamine, hexacosylamine, heptacosylamine, octacosylamine, nonacosylamine, triacontylamine, oleylamine, linoleylamine, erucamine, and ricinoleylamine. Linear, branched, saturated, or unsaturated aliphatic diamines with 6 to 30 carbon atoms For example, hexyldiamine, heptyldiamine, octanediamine, decanediamine, dodecanediamine, etc. may be mentioned. Linear or branched saturated or unsaturated aliphatic monoamides with 6 to 30 carbon atoms Examples thereof include hexanamide, heptaneamide, octaneamide, decanamide, dodecanamide, tetradecanamide, hexadecanamide, octadecanamide, eicosanamide, docosanamide, tetracosanamide, oleic acid amide, linoleic acid amide, linolenic acid amide, arachidonic acid amide, erucic acid amide, and the like, as well as aliphatic monoamides which are reaction products of the above-mentioned aliphatic monocarboxylic acids having from 6 to 30 carbon atoms with amines. Linear, branched, saturated, or unsaturated aliphatic diamides with 6 to 30 carbon atoms For example, an aliphatic diamide, which is a reaction product of the above-mentioned aliphatic dicarboxylic acid having 6 to 30 carbon atoms and an amine, can be mentioned. The amine used in producing the aliphatic monoamide or aliphatic diamide may be, for example, one or more selected from the above-mentioned aliphatic monoamines, methylamine, ethylamine, propylamine, butylamine, and pentylamine.

[0021] In the present invention, a combination of an aliphatic solvent having 6 to 12 carbon atoms (preferably 8 to 12 carbon atoms) and an aliphatic solvent having 13 to 30 carbon atoms (preferably 14 to 24 carbon atoms) can be used as the aliphatic solvent. As the aliphatic solvent, it is preferable to use one or more selected from aliphatic hydrocarbons, aliphatic monoalcohols, aliphatic monoesters, aliphatic diesters, aliphatic monoamides, and aliphatic diamides, and in particular, a combination of aliphatic hydrocarbons with aliphatic monoesters and / or aliphatic diesters can be used. The amount of aliphatic solvent to be added is not particularly limited, but is preferably 10% by weight or less (preferably 8% by weight or less) of the total amount of the composition, and if an aliphatic solvent is added, it is preferably 0.5% by weight or more.

[0022] Examples of thickeners that can be used include clay minerals such as sepiolite, palygorskite, bentonite, montmorillonite, hectorite, beidellite, saponite, nontronite, volconescoite, sauconite, stevensite, fluorohectorite, laponite, rectonite, vermiculite, illite, makatite, kanemite, illielite, magadiite, and Kenyaite; swelling silica; cellulose or a cellulose derivative; and polyacrylic acid polymers. The amount of thickener to be added is not particularly limited, but is preferably 0.1% by weight to 20% by weight, more preferably 0.5% by weight to 15% by weight, based on the total amount of the composition.

[0023] Examples of oxidizing agents include formic acid, acetic acid, butyric acid, acrylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, phthalic acid, maleic acid, fumaric acid, benzoic acid, salicylic acid, cinnamic acid, lactic acid, malic acid, citric acid, tartaric acid, ascorbic acid, aspartic acid, aminobenzoic acid, alginic acid, glycolic acid, gluconic acid, glutamic acid, toluenesulfonic acid, nicotinic acid, uric acid, halogen-substituted acetic acid, benzenesulfonic acid, hydrogen peroxide, perchlorates, and perborates.

[0024] Examples of reducing agents include sodium hydroxide, sodium polyphosphate, sodium carbonate, potassium hydroxide, lithium hydroxide, and calcium hydroxide.

[0025] The amount of the oxidizing agent and reducing agent mixed is not particularly limited, but the total amount is preferably 10% by weight or less, and more preferably 0% by weight or more and 5% by weight or less, based on the total amount of the composition.

[0026] Examples of resins include vinyl acetate resin, acrylic resin, urethane resin, polyester resin, etc. The form of the resin is not particularly limited and may be water-soluble, water-dispersible, solvent-soluble, NAD, self-emulsifying, powder, etc.

[0027] Examples of waxes include polyethylene wax and its derivatives, montan wax and its derivatives, microcrystalline wax and its derivatives, petrolatum, carnauba wax, candelilla wax, rice wax, Japan wax, lanolin, beeswax, Fischer-Tropsch wax, etc. They may be liquid or solid, and one or more types may be used. Liquid paraffin wax and its derivatives may also be used.

[0028] In addition, examples of the solvent other than the component (D) and the aliphatic solvent include ethylene glycol, diethylene glycol, propylene glycol, ethylene glycol mono-n-butyl ether, ethylene glycol mono-tert-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, ethylene glycol diacetate, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether, propylene glycol mono-n-butyl ether, dipropylene glycol monopropyl ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol dibutyl ether, diethylene glycol ethyl methyl ether, diethylene glycol dimethyl ... Glycols such as ethylene glycol diethyl ether, diethylene glycol dibutyl ether, dipropylene glycol dimethyl ether, triethylene glycol dimethyl ether, diethylene glycol monoethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, and diethylene glycol monobutyl ether acetate, as well as ethyl acetate, butyl acetate, dimethyl sulfoxide, hexamethylphosphoric triamide, N-methylpyrrolidone, sulfolane, chlorobutane, bromohexane, dichloromethane, 1,2-dichloroethane, 1,1-dichloroethane, chloroform, chlorinated polyethylene, chlorinated polypropylene, triglycerides, cyclohexanol, and furfuryl alcohol can also be used. In the present invention, it is preferable not to use chlorine-based solvents such as chlorobutane, bromohexane, dichloromethane, 1,2-dichloroethane, 1,1-dichloroethane, chloroform, chlorinated polyethylene, and chlorinated polypropylene from the viewpoint of odor, etc.

[0029] The stripper composition of the present invention can be obtained by mixing the above components. From the viewpoints of reducing environmental load, safety, workability, etc., the pH of the stripper composition of the present invention is preferably from 3 to 14, more preferably from 3.5 to 8, and particularly preferably from 4 to 7.

[0030] The stripping agent composition of the present invention is used to strip coating films formed on the surfaces of buildings, civil engineering structures, etc., and applicable coating films are not particularly limited, but examples thereof include JIS K5621 "General-purpose rust-preventive paints," JIS K5651 "Amino alkyd resin paints," JIS K5658 "Weather-resistant topcoat paints for architecture," JIS K5659 "Weather-resistant paints for steel structures," JIS K5660 "Glossy synthetic resin emulsion paints," JIS K5663 "Synthetic resin emulsion paints," JIS K5668 "Synthetic resin emulsion pattern paints," JIS K5670 "Acrylic resin-based non-aqueous dispersion paints," and JIS A6909 "Architectural finishing coating materials."

[0031] The release agent composition of the present invention may be applied to such a coating film at a rate of preferably 0.2 kg / m to 5.0 kg / m, more preferably 0.3 kg / m to 3.0 kg / m. The application tool is not particularly limited, and application may be performed using, for example, a roller, brush, trowel, spatula, spray gun, or the like.

[0032] Furthermore, the stripping agent composition of the present invention softens and begins to strip within 30 minutes to 2 hours, and the softening continues even after 24 to 48 hours. Therefore, stripping can be performed at the applicator's convenience, such as the next day. The stripping tool is not particularly limited, and stripping can be performed using, for example, a trowel, spatula, scraper, etc. The present invention has excellent durability of non-flammability after application, allowing for safe stripping. [Example]

[0033] The following examples will clarify the features of the present invention.

[0034] Remover compositions 1 to 16 were prepared by uniformly mixing the following raw materials in the weight proportions shown in Table 1. The pH of each of the remover compositions 1 to 16 was within the range of 4 to 6. A: Water B: Benzyl alcohol C: Solid paraffin (melting point 60°C) D1: Trimethylbenzene D2: Methyl phenyl ether E: Polyoxyethylene (20) lauryl ether sodium sulfate F: Glycerin Solvent: Nonane Liquid paraffin Thickener: Cellulose-based thickener

[0035] (Test 1) Non-flammable 1 kg of the obtained release agent composition was placed in a metal container (5 liters), the container was sealed with a lid, and the container was left to stand for 1 hour. After leaving it to stand, the lid was opened and an ignition rod was used to ignite the stripper composition near its surface, and the state of the stripper composition was observed. The evaluation was as follows. The evaluation results are shown in Table 1. 4: Even when ignited, it did not catch fire. 3: After ignition, a flash was observed, but the fire was extinguished within 1 second. 2: After ignition, a flash was observed, but the fire was extinguished within 5 seconds. 1: After ignition, ignition was observed and continued for more than 5 seconds.

[0036] (Test 2) Peelability The substrate was placed so that the coating surface shown below was vertical, and the stripping composition shown in Table 1 was applied with a roller in the required amount shown below, and the following tests were carried out. Coating surface: One side of a slate board (300 x 150 x 6 mm) was sprayed with an acrylic silicone resin paint primarily composed of acrylic silicone resin and titanium oxide to form a coating film 0.3 mm thick. This was then exposed to an accelerated weathering tester, "Eye Super UV Tester" (manufactured by Iwasaki Electric Co., Ltd.), for 400 hours to form the coating surface. The required amount of stripping composition was 0.5 kg / m². 24 hours after application, the coating was peeled off using a spatula, and the degree of peeling was evaluated on a 5-point scale from "5" (peelable smoothly without any problems, showing excellent coating film softening properties) to "1" (peel was difficult, showing poor coating film softening properties). The results are shown in Table 1.

[0037] (Test 3) Durability of non-flammability 1 kg of the coating film peeled off in Test 2 was placed in a metal container (5 liters), and ignited near the surface of the coating film using an ignition rod, and the condition of the coating film was observed. The evaluation was as follows. The evaluation results are shown in Table 1. 4: Even when ignited, it did not catch fire. 3: After ignition, a flash was observed, but the fire was extinguished within 1 second. 2: After ignition, a flash was observed, but the fire was extinguished within 5 seconds. 1: After ignition, ignition was observed and continued for more than 5 seconds.

[0038] [Table 1]

Claims

1. (A) water, and (B) an aromatic alcohol, An aqueous stripper composition comprising: Furthermore, (C) solid paraffin 0.01% by weight or more and 10% by weight or less, (D) an aromatic organic solvent having 6 to 15 carbon atoms, and an aliphatic solvent having from 6 to 30 carbon atoms; 1. An aqueous stripping composition comprising:

2. (A) Water 20% by weight or more and 60% by weight or less, (B) 40% by weight or more and 80% by weight or less of an aromatic alcohol; (C) solid paraffin 0.01% by weight or more and 10% by weight or less, (D) 0.1% by weight or more and 10% by weight or less of an aromatic organic solvent having 6 to 15 carbon atoms, and 0.5% by weight or more and 10% by weight or less of an aliphatic solvent having 6 to 30 carbon atoms, 1. An aqueous stripping composition comprising:

3. 3. The aqueous stripping composition according to claim 1, further comprising (E) a surfactant.

4. 4. The aqueous stripping composition according to claim 1, further comprising (F) a volatilization inhibitor.

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