JP2015007252A - Aqueous aerosol coating stock solution and aqueous aerosol coating composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous aerosol coating composition which can sufficiently reduce the amount of VOCs and is excellent in storage stability and coating film performance.SOLUTION: The aqueous aerosol coating composition includes 100 pts.mass of a coating stock solution and 50 pts.mass or more and 200 pts.mass or less of a propellant. The coating stock solution contains 15 mass% or more and 45 mass% or less in terms of the resin solid content of a dispersion resin having an average particle size of 10 nm or more and 100 nm or less, and 40 mass% or more and 80 mass% or less of water.

Description

  The present invention relates to an aqueous aerosol coating material stock solution and an aqueous aerosol coating composition.

  In recent years, water-based aerosol paints have become mainstream from organic solvent-type aerosol paints due to the influence on the natural environment and the like. The water-based aerosol paint is prepared by using a solvent in which a water-soluble resin or a water-dispersible resin is mixed with water while suppressing or avoiding the incorporation of a chlorinated organic solvent or a fluorocarbon propellant. However, water-based aerosol paints often have problems with coating properties such as drying properties, atomization properties, storage stability, and water resistance. In order to solve such problems, various water-based aerosol paints have been developed.

  For example, it has been proposed to use a non-chlorine glycol ether organic solvent and water as solvents and use a propellant other than chlorofluorocarbon (Patent Document 1). In addition, it has been proposed to use a carbon dioxide gas as a propellant for a water-soluble resin having an amino group to simultaneously ensure miscibility with the water-soluble resin (Patent Document 2). Furthermore, it has also been proposed to use a glycol ether water-soluble solvent and an amine compound for the O / W emulsion resin (Patent Document 3).

JP-A-5-70713 JP 2000-44839 A JP 2004-137428 A

  However, according to any of the above proposals, it has been difficult to ensure storage stability by sufficiently reducing the VOC amount and at the same time suppressing gelation. In addition to these, coating performance such as water resistance was not sufficient. That is, in Patent Document 1, a considerable amount of glycol ether solvent is used. According to Patent Document 2, water resistance is sufficient because a completely water-soluble resin is used to dissolve carbon dioxide gas. It is difficult to obtain coating film performance. Further, according to Patent Document 3, in order to prevent gelation due to the mixing of the propellant and the emulsion resin, a large amount of glycol ether solvent is also used.

  Therefore, in view of these conventional problems, the disclosure of the present specification provides an aqueous aerosol paint stock solution and an aqueous aerosol paint composition that can sufficiently reduce the amount of VOC and are excellent in storage stability and coating film performance. Objective.

  The present inventors have studied paying attention to the binder resin. It has been found that by using a dispersion resin as a binder, the use of a water-soluble organic solvent can be suppressed or avoided, and the miscibility with a propellant can be adjusted to produce a stable aerosol. Furthermore, it has also been found that the coating film obtained from the water-based aerosol paint thus obtained has excellent coating film performance. According to the disclosure of the present specification, the following means are provided.

  According to the disclosure of the present specification, a dispersion resin having an average particle diameter of 15% by mass to 45% by mass in a resin solid content of 10 nm to 100 nm, and water of 40% by mass to 80% by mass. An aqueous aerosol paint stock solution containing is provided.

  According to the disclosure of the present specification, a dispersion resin having an average particle diameter of 15% by mass to 45% by mass in a resin solid content of 10 nm to 100 nm, and water of 40% by mass to 80% by mass. There is provided an aqueous aerosol coating composition containing 50 parts by mass or more and 200 parts by mass or less of a propellant with respect to 100 parts by mass of the coating stock solution to be contained. The dispersion resin is preferably 20% by mass or more and 40% by mass or less. Further, the dispersion resin is preferably. Further, the composition may contain substantially no water-soluble organic solvent, or may contain 5% by mass or less of the water-soluble organic solvent. Furthermore, it may contain 20% by mass or less of pigment. Further, it may contain an amine compound.

  According to the disclosure of the present specification, a dispersion resin having a resin solid content of 25% by mass to 60% by mass, 30% by mass to 60% by mass water, and 1% by mass to 30% by mass pigment. A water-based aerosol paint comprising: a step of preparing a water-based aerosol paint stock solution by adding at least water to a paint stock solution containing a solution; and a step of preparing a water-based aerosol paint composition by adding a propellant to the water-based aerosol paint stock solution. A method of manufacturing the composition is provided. The step of preparing the aqueous aerosol paint stock solution may include a step of dispersing the pigment using an amine compound.

  The present disclosure relates to a water-based aerosol paint stock solution, a water-based aerosol paint composition, and a method for producing the same. According to the aqueous aerosol paint stock solution and the aqueous aerosol paint composition disclosed in the present specification, the use of a water-soluble organic solvent can be avoided or sufficiently suppressed by using a dispersion resin as a binder resin. Moreover, gelatinization can be suppressed at the time of mixing with a propellant by using the dispersion resin of a predetermined average particle diameter. Furthermore, for this reason, the use of a water-soluble organic solvent can be avoided or sufficiently suppressed. Furthermore, according to the dispersion resin, a coating film having good performance can be obtained.

  A dispersion resin is known as a binder resin for water-based paints together with a water-soluble resin and an emulsion resin. The dispersion resin has intermediate properties between the water-soluble resin and the emulsion resin. For dispersion resins, water-soluble organic solvents can be reduced, but water-based aerosol paints are sometimes used due to problems such as gelation and dispersibility of pigments when mixed with propellants. It was not used. The present inventors use a dispersion resin having a constant average particle diameter and adjust the pH of the stock solution in preparation for a decrease in pigment dispersibility when mixed with a propellant, or a gel with a propellant. It was difficult to use it for aerosol paints due to the problem of chemical conversion. Hereinafter, various embodiments disclosed in this specification will be described in detail.

(Water-based aerosol paint stock solution)
The aqueous aerosol coating composition disclosed in the present specification contains a dispersion resin as a binder resin. Examples of the dispersion resin include polyacrylic acid, polymethacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, vinyl acetate-acrylic acid ester copolymer, acrylic acid-acrylic acid alkyl ester. Acrylic resins such as copolymers; styrene-acrylic acid copolymers, styrene-methacrylic acid copolymers, styrene-methacrylic acid-alkyl acrylate copolymers, styrene-α-methylstyrene-acrylic acid copolymers Styrene- (meth) acrylic acid copolymer resins such as styrene-α-methylstyrene-acrylic acid-alkyl acrylate copolymer; vinyl naphthalene-acrylic acid copolymer; vinyl naphthalene-maleic acid copolymer; acetic acid Vinyl-ethylene copolymer, acetic acid Vinyl acetate resins such as vinyl-fatty acid vinyl-ethylene copolymer, vinyl acetate-maleic acid ester copolymer, vinyl acetate-crotonic acid copolymer, vinyl acetate-acrylic acid copolymer; polyvinyl chloride, polychlorinated Vinyl chloride resins such as vinylidene, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl propionate copolymer; polyol resins such as polyvinyl butyral; polyolefin resins such as polyethylene and polypropylene; styrene-butadiene resins; acrylonitrile-butadiene Resin; isoprene resin; chloroprene resin; polyurethane resin and the like. One of these dispersion resins may be used alone, or two or more thereof may be used in combination. Among the dispersion resins, acrylic resins, styrene- (meth) acrylic acid copolymer resins, and polyurethane resins can be used.

  The average particle size of the dispersion resin is preferably 10 nm or more and 100 nm or less. Within this range, gelation can be avoided during mixing with the propellant. Preferably, the average particle diameter is 50 nm or more and 100 nm or less. Such average particle diameter can be measured by a dynamic light scattering method. Specifically, such an average particle diameter can be measured using a nanotrack particle size distribution analyzer UPA (manufactured by Nikkiso Co., Ltd.).

  In the aqueous aerosol coating material stock solution, it is preferable to contain 15% by mass or more and 45% by mass or less of such a dispersion resin in terms of resin solid content. Within this range, an aqueous aerosol having an appropriate resin content when mixed with an acceptable amount of propellant, that is, a resin content of 15% to 45% by weight, preferably 20% to 40% by weight. A coating composition can be obtained.

  The aqueous aerosol paint stock solution can contain 40% by mass or more and 80% by mass or less of water. By containing water in this range, the amount of the soluble organic solvent used can be reduced while ensuring the dispersibility of the dispersion resin. Moreover, the drying property of a coating film is securable. More preferably, it is 50 mass% or more and 80 mass% or less, More preferably, it is 50 mass% or more and 75 mass% or less.

  It is preferable that the water-based aerosol paint stock solution does not substantially contain a water-soluble organic solvent. Since the dispersion resin is used, resin dispersibility can be ensured without using a glycol ether-based water-soluble organic solvent. In addition, the water-based aerosol paint stock solution may contain 5 mass% or less. If it is 5 mass% or less, the influence of the organic solvent is sufficiently suppressed even in the working environment and the natural environment. Examples of the water-soluble organic solvent include glycol ether water-soluble solvents. Examples thereof include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, and ethylene glycol monoisobutyl ether. Among these glycol ethers, ethylene glycol monomethyl ether and ethylene glycol monoethyl ether are desirable for better drying properties, and ethylene glycol monoisobutyl ether is desirable from the viewpoint of health and safety. These glycol ethers may be used alone or in combination of two or more. In addition, examples of other water-soluble organic solvents include higher alcohols such as n-butanol, amyl alcohol, hexyl alcohol, cyclohexyl alcohol, benzyl alcohol, and octyl alcohol.

  The aqueous aerosol paint stock solution may or may not contain a pigment. When a pigment is included, the content is preferably 30% by mass or less. This is because if it exceeds 30% by mass, it becomes difficult to obtain a highly glossy coating film. More preferably, it is 20 mass% or less. As the pigment, pigments used in general aerosol paints can be used almost without restriction. Although not particularly limited, for example, inorganic pigments such as titanium white (titanium oxide), carbon black, bengara, organic pigments such as cyanine blue, cyanine green, and permanent red, extender pigments such as calcium carbonate, talc, and clay, urethane beads, etc. Particulate bead pigments, pearl pigments, various dyes, and the like. Only one pigment may be used, or two or more pigments may be used in combination.

  When the aqueous aerosol paint stock solution contains a pigment, the dispersibility of the pigment may be reduced depending on the type of pigment when preparing the aqueous aerosol paint composition by mixing the aqueous aerosol paint stock solution and the propellant. is there. When such a pigment is used, it is preferable to adjust the pH using a pH adjusting agent such as an acid or an alkali in the coating solution. Examples of the pH adjuster include various acids such as inorganic acids and organic acids, inorganic alkalis such as NaOH, and various amine compounds. Although depending on the type of pigment, amine compounds and the like are preferably used. The amine compound is not particularly limited, and examples thereof include ammonia, diethylamine, triethylamine, monoethanolamine, diethanolamine, triethanolamine, dimethylethanolamine, and diethylethanolamine.

  The range of pH to be adjusted varies depending on the type and amount of pigment. An appropriate pH range can be obtained by preparing a water-based aerosol paint stock solution containing various pigments and various pHs, mixing these with a certain amount of propellant, and observing the aerosol state visually. Therefore, by obtaining in advance the pH range of the aqueous aerosol paint stock solution appropriate for obtaining an aqueous aerosol coating composition for each pigment, it is possible to reliably obtain an aqueous aerosol coating composition free from pigment aggregation. . For example, in the case of titanium dioxide, good dispersibility can be ensured even when propellant is mixed within the range of pH 7.9 to pH 10.2. In addition, with respect to carbon black, it is not always necessary to adjust pH, and by mixing a water-based aerosol paint stock solution in the range of pH 7.3 to 7.6 obtained without adjusting pH with a propellant, the carbon black can be satisfactorily obtained A dispersed coating composition can be obtained.

  The aqueous aerosol paint stock solution may appropriately contain additives such as dispersants, antifoaming agents, film-forming aids, leveling agents, and surfactants used in conventional aqueous aerosol paint compositions. Such additives can be used without any particular limitation. This aqueous aerosol paint stock solution can be used as it is, or as a water-based paint composition for application by spray application after adjusting the viscosity with a diluent (solvent).

  The aqueous aerosol paint stock solution can be prepared, for example, by the following method. That is, first, a dispersion resin having a resin solid content of 25% by mass to 60% by mass, water of 30% by mass to 60% by mass, and optionally 1% by mass to 30% by mass of pigment, If necessary, a coating stock solution containing an additive such as a film-forming aid and a leveling agent, and further containing a water-soluble organic solvent as needed is prepared. An aqueous aerosol paint stock solution can be obtained by adding and mixing at least water to the paint stock solution and adjusting the pH with a pH adjuster as necessary.

(Water-based aerosol coating composition)
The aqueous aerosol coating composition disclosed in the present specification is prepared by mixing a propellant with such an aqueous aerosol coating stock solution. The propellant is not particularly limited, and for example, a hydrophilic (water-soluble) propellant such as dimethyl ether, or a hydrophobic propellant such as liquefied petroleum gas (LPG) or hydrocarbon can be used. These may be used alone or in combination of two or more. Preferably, a hydrophilic propellant is used, and more preferably only a hydrophilic propellant is used. The propellant is preferably contained in an amount of 50 parts by mass or more and 200 parts by mass or less with respect to 100 parts by mass of the coating material stock solution. More preferably, it is 50 to 100 parts by weight.

  The water-based aerosol coating composition disclosed in this specification is a water-based aerosol paint stock solution by adding at least water and, if necessary, a pH adjuster to the above-mentioned paint stock solution, and a propellant is added to the water-based aerosol paint stock solution. Aerosol paint compositions may be prepared. Moreover, as already demonstrated, the water-based aerosol coating composition disclosed by this specification can be prepared also with the following method, for example. That is, a pigment is added to the dispersion resin and a part or all of water, and after stirring and mixing with a dispersion or the like, it is dispersed with a sand grind mill. If necessary, the remaining amount of the dispersion resin and water is added, and after adding an additive such as an antifoaming agent, the aqueous aerosol coating stock solution is obtained by uniformly stirring and mixing with the disper. An aqueous aerosol coating composition can be obtained by filling an aerosol spray can with the aqueous aerosol coating material stock solution and the propellant at a predetermined mixing ratio.

  Hereinafter, the disclosure of the present specification will be specifically described with reference to examples. However, the present invention is not limited to the following examples.

  In this example, while preparing various paint stock solutions shown in Table 1, water, an antifoaming agent and, if necessary, a pH adjuster (25% by mass ammonia water) were added to the stock solution and mixed. A water-based aerosol paint stock solution was obtained. Dimethyl ether (DME) was also added to the aqueous aerosol coating material stock solution at the ratio shown in Table 1 to obtain various aqueous aerosol coating compositions of Examples 1 to 6 and Comparative Examples 1 to 4. As the acrylic dispersion resin, one having an average particle diameter of 50 nm or more and 100 nm or less was used. In Table 1, as the antifoaming agent, Sannopco silicone antifoaming agent SN deformer 381 was used. The paint stock solution, aqueous aerosol paint stock solution and aqueous aerosol paint composition were prepared according to conventional methods.

  The following items were evaluated for the water-based aerosol coating composition finally obtained. These results are also shown in Table 1.

(1) Aerosolization The state at the time of mixing with a propellant was observed visually, and it was set as (circle) that there is no aggregation of a pigment.
(2) Appearance of coating film A test piece (SPCC-SB steel plate (JIS G3141) was coated with an aqueous aerosol coating composition so that the dried coating film would be 5 μm to 10 μm, and 4 at room temperature 23 ° C. and humidity 50% RH or less. A sample was prepared by drying for days, and the appearance of this sample was evaluated according to a standard according to JISK5600-1-1.
<Criteria>
○: No repelling or sagging and good leveling ×: Possing or sagging, poor leveling (3) Adhesion (cross-cut method)
The sample prepared in the same manner as (2) was evaluated according to JIS K5600-5-6 (cut interval: 1 mm, square: 100).
<Criteria> (Number of remaining squares)
○: 100/100
Δ: 90 to 99/100
×: Less than 90/100 (4) Moisture resistance (continuous condensation method)
The sample prepared in the same manner as (2) was evaluated according to JIS K5600-7-2 (temperature 50 ° C., humidity 95%, 72 hours).
<Criteria>
○: No deterioration in coating film ×: Deterioration in coating film (5) Water resistance (liquid resistance (water immersion method))
The sample prepared in the same manner as (2) was evaluated according to JIS K5600-6-6-2 (23 ° C., 3 days).
<Criteria>
○: No deterioration in coating film ×: Deterioration in coating film

  As shown in Table 1, in the aqueous aerosol coating compositions shown in Examples 1 to 6, good results were obtained for both aerosolization and coating performance. That is, when a dispersion resin is used, the use of a water-soluble organic solvent can be avoided or suppressed (4% by mass or less in the coating stock solution, 3% by mass or less in the aqueous aerosol coating stock solution), and a substantially complete aqueous aerosol coating composition. Can provide things. Moreover, the gelation of the resin can be avoided and the storage stability is excellent, and a coating film excellent in coating film physical properties can be obtained even if it is aqueous. On the other hand, according to Comparative Examples 1 and 2, with respect to carbon black, when an appropriate pH range was not ensured in the aqueous aerosol coating material stock solution, problems occurred in aerosolization and physical properties of the coating film. In addition, it was found that when the content of the dispersion resin is 46% by mass or more or 13% by mass or less in the aqueous aerosol paint stock solution, the physical properties of the coating film are deteriorated. Therefore, it was found that the dispersion resin is preferably 15% by mass or more and 45% by mass or less in the aqueous aerosol coating material stock solution. More preferably, it was found to be 20% by mass or more and 40% by mass or less.

Claims (11)

A dispersion resin having a resin solid content of 15% by mass to 45% by mass;
40% by mass or more and 80% by mass or less of water;
A water-based aerosol paint stock solution containing A dispersion resin having a resin solid content of 15% by mass to 45% by mass;
40% by mass or more and 80% by mass or less of water;
An aqueous aerosol coating composition containing 50 parts by mass or more and 200 parts by mass or less of a propellant with respect to 100 parts by mass of a coating stock solution containing.   The aqueous aerosol coating composition according to claim 2, wherein the dispersion resin is 20 mass% or more and 40 mass% or less.   The water-based aerosol coating composition according to claim 2 or 3, wherein the dispersion resin contains particles having an average particle diameter of 10 nm to 100 nm.   The aqueous aerosol coating composition according to any one of claims 2 to 4, comprising 5% by mass or less of a water-soluble organic solvent.   The aqueous aerosol coating composition according to any one of claims 2 to 4, which contains substantially no water-soluble organic solvent.   Furthermore, the water-based aerosol coating composition in any one of Claims 2-6 containing 20 mass% or less of pigments.   Furthermore, the water-based aerosol coating composition of Claim 7 containing a pH adjuster.   The water-based aerosol coating composition according to any one of claims 2 to 8, wherein the propellant is a hydrophilic propellant. A method for producing an aqueous aerosol coating composition comprising:
At least water in a coating stock solution containing a dispersion resin having a resin solid content of 25% by mass or more and 60% by mass or less, 30% by mass or more and 60% by mass or less of water, and 1% by mass or more and 30% by mass or less of pigment. Adding a water-based aerosol paint stock solution,
And adding a propellant to the aqueous aerosol coating composition to prepare an aqueous aerosol coating composition. The method according to claim 10, wherein the step of preparing the aqueous aerosol paint stock solution includes a step of dispersing the pigment using a pH adjuster.