JPS6134473B2 - - Google Patents

Description

[Detailed description of the invention]

This invention relates to water-based aerosol paints. More specifically, it relates to a water-based aerosol paint that is weakly flammable and is not classified as a dangerous substance under the Fire Service Act. Generally, solvent-type aerosol paints are made by dissolving natural or synthetic resin as a vehicle component in a solvent, adding a propellant to this, adding pigments and additives as appropriate, and storing these in a spray container. Organic solvents such as toluene, ethyl acetate, and methyl ethyl ketone are used to dissolve the resin. However, these solvents are highly flammable and dangerous to handle, many of which are harmful to the human body, and are often a source of pollution during production. It had the following drawbacks. Focusing on these points, various attempts have been made to make aerosol paints non-hazardous and weakly flammable or non-flammable. On the other hand, the properties fundamentally required for an aerosol paint include adhesion, gloss, atomization of mist during spraying, and uniform mist formation, including sprayability.
It exhibits water and weather resistance, stability without settling, gelling, or thickening in the container during storage, smoothness of the coating after spray painting, anti-sagging properties, and foaming property immediately after painting. However, in the past, the compatibility between the resin and propellant, which is an essential component of aerosol paints, was poor, and various properties such as sprayability and stability, especially low flammability, were considered. I couldn't find anything that would satisfy me. In view of the above points, the present inventors have provided an aerosol paint that is weakly flammable, has no risk of being dangerous, harmful, or a source of pollution, and is not classified as a dangerous substance under the Fire Service Act. As a result of various research aimed at this purpose, we have developed a new technology that uses a water-dispersible resin instead of the conventional organic solvent-soluble resin, and also combines water, a water-soluble organic solvent, and a nonflammable organic solvent as solvents, making it easier to handle. The present invention was achieved by discovering that it is easy and safe to obtain a non-hazardous, weakly flammable water-based aerosol paint that has a quality equal to or higher than that of conventional solvent-based aerosol paints. That is, the present invention provides an aerosol paint containing a resin as a vehicle component, a solvent, and a propellant, and optionally a pigment and/or an additive, in which a water-dispersible resin is used as the resin, and water is used as the solvent. , a water-based aerosol paint characterized by using a mixed solvent consisting of three components: a water-soluble organic solvent and a nonflammable organic solvent. The water-dispersible resins used in this invention include vinyl acetate emulsion, acrylic emulsion, vinyl acetate-acrylic copolymer emulsion, vinyl acetate-veova copolymer emulsion, and acrylic-acrylic emulsion.
Examples include emulsion resins such as Beoba copolymer emulsion and alkyd emulsion. The mixed solvent used in the present invention is composed of three components: water, a water-soluble organic solvent, and a nonflammable organic solvent, and it disperses the water-dispersible resin component, has good dispersibility of the color pigment, and has good compatibility with the propellant. A component is selected that has good properties and is mildly flammable during storage and injection of the aerosol paint. Examples of water-soluble organic solvents include alcohols such as methanol, ethanol, butanol, propanol, and isopropanol; ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone;
Methyl acetate, ethyl acetate, n-propyl acetate,
Esters such as isopropyl acetate and n-butyl acetate, and ethers such as methyl cellosolve, ethyl cellosolve, butyl cellosolve, and methyl cellosolve acetate are used alone or in combination. As the nonflammable organic solvent, halogenated hydrocarbons and dioxane, such as trichloromonofluoromethane, tetrachlorodifluoroethane, trichlorotrifluoroethane, and dibromotetrafluoroethane, which have a low boiling point, are preferably used. The propellant used in the present invention is a gas at room temperature, has good compatibility with the water-dispersible resin and solvent, satisfies properties such as sprayability and stability, and is nonflammable or weakly flammable ( Particularly during injection), halogenated hydrocarbons such as trichloromonofluoromethane, dichloromonofluoromethane, and dichlorotetrafluoroethane are selected. Dimethyl ether (DME) or a mixture of dimethyl ether and liquefied petroleum gas (LPG) can be used in an amount that maintains weak flammability when combined with a solvent or the like. As the pigment, there are no special pigments, and publicly known titanium white, Lake Red B, yellow lead, phthalocyanine blue, carbon black, etc. can be used, and they can be used in the form of a color paste dispersed in the water-dispersible resin, or as a powder. Pigments are mixed and prepared separately before use. In order to improve various properties such as quality stability and long-term shelf life of the aerosol paint, known additives such as a matting agent, anti-settling agent, anti-foaming agent, anti-sagging agent, and rust preventive agent are added. be able to. In this invention, the water-dispersible resin, water, water-soluble organic solvent, nonflammable organic solvent, and propellant can be mixed in any proportion. However, the properties required for an aerosol paint, namely the above-mentioned mist forming property and good sprayability,
In order to satisfy the stability and compatibility with propellants, etc., and to make it weakly flammable and not similar to dangerous substances under the Fire Service Act, it is necessary to use a water-dispersible resin of 5 to 30% by weight, Water 1-15%, water-soluble organic solvent 3-30%
%, nonflammable organic solvent 5-20%, and propellant 40-65%. In particular, the amount of water-dispersible resin as a vehicle component is preferably 15 to 25% in order to improve coating film formation, smoothness, and pigment development and dispersion after spraying the paint. Furthermore, if the amount of water added is less than 1%, the stability of the paint including the water-dispersible resin is poor, and if it is more than 15%, not only the drying of the sprayed paint film is slow, but also the corrosion of the spray container is accelerated. . If the amount of water-soluble organic solvent added is less than 3%, the stability of the resin will be poor as described above, and if it is more than 30%, it will become a dangerous substance under the Fire Service Act when spraying paint, and it will not be considered a non-hazardous substance as the purpose of the present invention. A weakly flammable aerosol paint cannot be obtained. The same applies to the amount of nonflammable organic solvent added. Next, the amount of colored pigment added varies depending on whether the paint is translucent or opaque, and the type of pigment such as white pigment, yellow pigment, blue pigment, etc., but assuming the above composition is 100, the weight It can be blended arbitrarily within the range of 7% or less for translucent paints and 0.5 to 25% for opaque paints. If no colored pigment is added, the paint becomes a transparent paint. Additives are usually 0.5 by weight based on the above composition as 100.
It is sufficient to add ~2%. Next, the present invention will be specifically explained using examples. Example 1 Ingredients Parts by weight (a) Acrylic resin emulsion 24.4 (b) Water 6.1 (c) Butyl cellosolve 12.2 (d) Trichlorotrifluoroethane 12.2 (e) Dimethyl ether 45.1 total 100.0 Acrylic resin emulsion and butyl cellosolve were mixed, and the following Water and trichlorotrifluoroethane were added thereto and mixed uniformly to obtain a resin solution with a specified viscosity, which was then placed in a spray container and filled with dimethyl ether as a propellant to prepare a transparent aqueous aerosol paint. Compared to conventional organic solvent-based aerosol paints (reference examples described below), this product had the same or better sprayability, anti-sagging properties, foaming properties, and long-term stability, and the following test results were obtained.

[Table] The above spray suitability is based on the coating applied to a JIS G3141 cold-rolled steel plate 0.3 x 70 x 150 (hereinafter referred to as the coated plate) through a fixed nozzle at a fixed temperature (20°C) for a fixed period of time. The situation was observed and compared and contrasted with the conventional example. Sagging resistance was determined by applying a certain amount of paint to a board to be coated from a distance of 20 cm at a constant temperature (20°C), standing the board vertically after painting, and comparing and contrasting the sagging of the paint film with conventional examples. Foaming properties were determined by placing the coated plate horizontally and observing the foaming status in the same manner as in the anti-sagging test above.
Judgment was made based on whether the bubbles disappeared by the end of drying. In addition, long-term stability is determined by the ability to form mist after storage for a certain period of time,
A method was used to compare and contrast the occurrence of cake (sedimentation degree of pigment) in the can, corrosion of the can, etc. with conventional examples. Example 2 Raw materials Parts by weight (a) Acrylic resin emulsion 23.0 (b) Water 5.8 (c) Butyl cellosolve 11.6 (d) Trichlorotrifluoroethane 11.6 (e) DME and LPG mixture 47.3 (f) Matting agent (thyroid) HS-204 0.7 total 100.0 A semi-gloss transparent aqueous aerosol paint was prepared in the same manner as in Example 1, except that the matting agent was uniformly dispersed and mixed in the acrylic resin emulsion and butyl cellosolve. Example 3 Ingredients Parts by weight (a) Vinyl acetate emulsion 18.5 (b) Water 3.5 (c) Butyl cellosolve 9.5 (d) Trichlorotrifluoroethane 8.5 (e) Dimethyl ether 46.5 (f) Titanium white 13.5 Total 100.0 Vinyl acetate emulsion and titanium white After mixing, a part of butyl cellosolve was added and kneaded to prepare a paste in which the titanium white pigment was uniformly dispersed.Water, the remainder of butyl cellosolve, and trichlorotrifluoroethane were added to this paste to dilute it, and the specified resin was mixed. This was made into a viscous solution, placed in a spray container, and then filled with dimethyl ether as a propellant to prepare an opaque water-based aerosol paint.Example 4 Raw materials Parts by weight (a) Vinyl acetate emulsion 18.5 (b) Water 3.5 ( c) Ethyl cellosolve 9.5 (d) Trichlorotrifluoroethane 8.5 (e) Dimethyl ether 46.5 (f) Titanium white 11.5 Phthalocyanine blue 2.0 total 100.0 Same as Example 3 except that titanium white and phthalocyanine blue were used instead of titanium white. By operation,
An opaque blue aqueous aerosol paint was prepared. Example 5 Raw materials Parts by weight (a) Bi-acetic acid ethylene copolymer emulsion 15.5 (b) Water 3.4 (c) Butyl cellosolve 1.0 Ethyl cellosolve 3.6 (d) Dibromotetrafluoroethane 10.3 (e) Liquefied petroleum gas 47.3 (f) Yellow Lead 18.9 total 100.0 Opaque yellow with a high pigment (yellow) content was produced using the same procedure as in Example 3, except that acetic acid-ethylene copolymer emulsion was used instead of vinyl acetate emulsion and yellow lead was used instead of titanium white. An aerosol paint was prepared. Example 6 Raw materials Parts by weight (a) Acrylic-veova copolymer emulsion 21.0 (b) Water 4.2 (c) Butyl cellosolve 2.3 Ethyl cellosolve 8.5 (d) Trichlorotrifluoroethane 9.6 (e) Dimethyl ether 52.8 (f) Yellow lead 1.6 Total 100.0 A translucent yellow aerosol paint was prepared in the same manner as in Example 3, except that an acrylic-beova copolymer emulsion was used instead of the vinyl acetate emulsion and yellow lead was used instead of titanium white. Comparative Example 1 Raw materials Parts by weight (a) Acrylic resin emulsion 19.0 (b) Water 20.0 (c) Butyl cellosolve 3.8 (d) Tetrachlorodifluoroethane 3.0 (e) Dimethyl ether 45.0 (f) Titanium white 9.0 Total 100.0 Same as Example 3 In operation, an opaque aqueous aerosol paint with a high water content was prepared. Comparative Example 2 Raw materials Parts by weight (a) Acrylic resin emulsion 33.0 (b) Water 5.7 (c) Butyl cellosolve 1.4 Ethyl cellosolve 5.1 (d) Trichlorotrifluoroethane 3.8 (e) Dimethyl ether 42.5 (f) Titanium white 8.5 Total 100.0 Example An opaque aqueous aerosol paint with a high resin content was prepared in the same manner as in Example 3. Reference Example An example of the composition of a conventional solvent-based aerosol paint is shown below. Raw materials Parts by weight Solvent type acrylic resin 7.6 CAB resin 12.5 Organic mixed solvent 21.9 Plasticizer 0.2 Pigment (titanium white) 2.7 Propellant 55.0 Co dryer 0.02 Pb dryer 0.09 Total 100 Next, Examples 2 to 6 and Comparative Examples 1 to 2 Test results of various aerosol paints prepared with conventional products (reference example)
A comparison is shown in the table below.

【table】

[Table] As shown in the table, the transparent to opaque aqueous aerosol paints described in Examples 1 to 6 are all weakly flammable and take some time to dry, but their impact resistance and water resistance are The various physical properties are equivalent to or higher than those of the conventional solvent-based aerosol paint of the reference example.
In addition, it also has good properties as an aerosol paint, such as spray suitability, anti-sag properties, and long-term stability. When the water or water-dispersible resin component is excessively large as in Comparative Examples 1 and 2, the composition cannot withstand use in terms of spray suitability, long-term stability, flammability, etc. Since the present invention is as described above, it is possible to provide a water-based aerosol paint that has a quality equal to or higher than that of conventional solvent-based aerosol paints and is easy to handle. In addition, by appropriately blending water-dispersible resin, water, water-soluble solvents, nonflammable solvents, etc., it has low flammability and there is no risk of becoming a source of pollution harmful to the human body. It is possible to provide a water-based aerosol paint that is safe to handle and use because it is not similar to dangerous substances, and does not require special facilities even when stored in large quantities.

Claims (1)

[Claims] 1. In an aerosol paint containing a resin as a vehicle component, a solvent, and a propellant, and optionally a pigment and/or an additive, a water-dispersible resin is used as the resin, and water or a water-soluble organic solvent is used as the solvent. and a nonflammable organic solvent, and the weight composition is 5 to 30% water-dispersible resin as a vehicle component, 1 to 15% water as a solvent, 3 to 30% water-soluble organic solvent, and A water-based aerosol paint characterized by having 100% of the ingredients consisting of 5 to 20% nonflammable organic solvent and 40 to 65% propellant.