JP5932271B2 - Film formation method - Google Patents

Description

  The present invention relates to a film forming method applicable to buildings and the like.

  Conventionally, various materials are used as a material constituting a wall surface of a building. Such materials are given various colors to enhance aesthetics. Furthermore, in order to maintain the aesthetics of the color over a long period of time, it is possible to prevent dirt and the like with a transparent film.

  For example, in Japanese Patent Application Laid-Open No. 2001-149855 (Patent Document 1), a colored film containing a high weather resistance binder as a film forming element is provided on a base material such as a ceramic building material or a concrete wall, It is described that a photocatalytic transparent coating is provided thereon. Japanese Patent Application Laid-Open No. 2008-246340 (Patent Document 2) describes that a sealer film, a colored film, and a transparent film are sequentially provided on the surface of the exterior material.

However, in the method of the above-mentioned patent document, when forming the transparent film, there is a possibility that problems such as unpainted and uneven coating occur. When such a defect occurs, a uniform transparent film is not formed, and the colored film is not sufficiently protected. Therefore, careful work is required so that the defect does not occur.
Moreover, the color obtained by the method of the above-mentioned patent document is a single color, and there is room for improvement in terms of aesthetics.

JP 2001-149855 A JP 2008-246340 A

  The present invention has been made in view of the above-described problems, and in a film forming method for protecting a colored film with a transparent film, efficiently forming the transparent film and further improving the aesthetics of the formed film. It is for the purpose.

  As a result of intensive studies to achieve the above object, the present inventor has formed a transparent coating using a coating liquid containing a fading dye, etc. The present inventors have conceived a method for forming and completed the present invention.

That is, the present invention has the following characteristics.
1. A film forming method for protecting a colored film with a transparent film,
A first step of forming a colored coating on the ground;
A second step of applying a coating solution containing a binder capable of forming a transparent coating, a fading dye, an aqueous medium, and metal ions on the colored coating;
The fading dye has a monovalent anionic group selected from a halogen group, a carboxylic acid group, and a sulfuric acid group,
The metal ion is a metal ion containing a divalent or higher valent metal element selected from Group 2 elements ;
The colored film in the first step is a mixture of two or more colored regions, and at least one color of the colored region has an L ^* value of 80 or more, an a ^* value of −3 to 3, and a b ^* value of A method of forming a film, characterized in that the film is colored so that the color tone before fading of the fading dye in the second step is visible.
2. 1. The concentration of metal ions in the coating solution (concentration of metal ions contained in 1 liter of aqueous medium) is 1-1000 mg / L. The film formation method of description.
3. At least one color in the colored region has an L ^* value of 85 or more, an a ^* value of −2.5 to 2.5, and a b ^* value of −2.5 to 13. Or 2. The film formation method of description.

  According to the present invention, a transparent coating can be efficiently formed, and the colored coating can be reliably protected by the transparent coating. Furthermore, in the present invention, a finished appearance with a rich color can be obtained.

  Hereinafter, modes for carrying out the present invention will be described.

  The present invention is a film forming method for protecting a colored film with a transparent film. First, as a first step, a colored film is formed on a base.

  In the present invention, the base to be painted is mainly a wall surface of a building, a civil engineering structure, or the like. Examples of the material constituting such a base include concrete, mortar, cement board, extrusion board, slate board, PC board, ALC board, fiber reinforced cement board, metal siding board, ceramic siding board, ceramic board Calcium silicate board, gypsum board, plastic board, hard wood cement board, PVC extrusion siding board, plywood and the like. These may have been subjected to some surface treatment (filler treatment, putty treatment, surfacer treatment, sealer treatment, etc.), or may have already been provided with a film or have a wallpaper attached thereto.

  In addition, such a base is a material having a joint pattern due to a linear recess, for example, a wall surface made of ceramic tiles, a coating surface provided with a texture having a joint pattern, or an inorganic building material having a joint pattern. It may be a configured wall surface or the like.

  In the present invention, a colored coating is formed on the base as described above. This colored film contains two or more colored areas, and at least one color of the colored areas is colored so that the color tone before fading of the fading dye in the second step can be visually recognized. In this invention, the coating state can be confirmed in a predetermined location at the time of coating liquid application in a 2nd process by forming the colored film which has such a colored region. Therefore, the work efficiency at the time of forming the transparent coating is increased, the occurrence of defects such as unpainted coating and uneven coating is suppressed, and the colored coating can be reliably protected by the transparent coating. Moreover, aesthetics can be improved by mixing a plurality of colored regions.

What is necessary is just to make it the color tone of each coloring area | region in a coloring film satisfy | fill the said conditions with at least 1 color. In the present invention, at least one color of the colored region is preferably L ^* value 80 or more, a ^* value −3 to 3, b ^* value −3 to 15, L ^* value 85 or more, a ^* value −2 It is more preferable that it is 5-2.5 and b ^* value -2.5-13. A colored film having such a colored region is suitable from the viewpoint of the effects of the present invention. In the present invention, L ^* , a ^* , and b ^* are values in the CIE L ^* a ^* b ^* color space and are measured by a spectrophotometer.

A colored film in which two or more colored regions are mixed can be formed by, for example, the following method.
(1) Method of using two or more colored coating materials having different color tones (2) Method of using a coating material containing two or more colored particles having different color tones

First, the method (1) will be described.
In the method (1), a colored coating may be formed using two or more kinds of colored coating materials having different color tones so that two or more colored areas are mixed. In particular,
-A method of partially applying the second colored coating material after the first colored coating material is applied to the whole-A method of partially applying the first colored coating material and the second colored coating material, respectively It is done. The shape of each colored region when the colored coating is viewed from the front is not particularly limited. For example, the shape of a square, rectangle, circle, ellipse, triangle, rhombus, polygon, indefinite shape, streaks, lattice shape, etc. Can be mentioned.

  As the colored coating material in the above (1), a coating material containing a binder and a coloring pigment as essential components may be used. Among these, examples of the binder include acrylic resin, urethane resin, epoxy resin, vinyl acetate resin, silicon resin, fluorine resin, acrylic vinyl acetate resin, acrylic urethane resin, acrylic silicon resin, and the like. Two or more types can be used. As the synthetic resin, an aqueous resin such as a water-dispersible resin (resin emulsion) or a water-soluble resin is suitable.

  Known coloring pigments can be used, such as titanium oxide, zinc oxide, carbon black, graphite, black iron oxide, copper chrome black, cobalt black, copper manganese iron black, red rose, molybdate orange, permanent red, Permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, first yellow, benzimidazolone yellow, chrome green, cobalt green, phthalocyanine green, ultramarine, bituminous, cobalt blue, phthalocyanine blue, quinacridone violet, di And oxazine violet. These can be used alone or in combination of two or more. The color tone of the colored coating material can be appropriately set by adjusting the type, mixing amount, and the like of the colored pigment. In the above (1), one or more of the colored coating materials may be adjusted to a color tone that allows the initial color tone of the fading dye in the second step to be visually recognized.

  When the ground has a joint pattern with linear recesses, the linear recesses and other portions can be applied in different colors. Such coating is performed by coating a colored coating material (first colored coating material) of a color tone appearing in a linear recess on the entire surface, and then using a colored coating material (second colored coating material) of a different color from the coating material. It can carry out by the method etc. which roller-coat parts other than a shape recessed part. In this case, one or both of the first colored coating material and the second colored coating material may be colored in a color tone that allows the initial color tone of the fading dye in the second step to be visually recognized.

For the coating of the colored covering material, for example, a known applicator such as a spray, a roller or a brush can be used. The coating amount of the colored coating material is preferably about ²⁰ to 400 g / m ^{2 in} terms of solid content, although it depends on the form of the coating material and the colored region. At the time of coating, a diluent such as water can be mixed to appropriately adjust the viscosity. The colored coating material may be normally dried at room temperature.

Next, the method (2) will be described.
In the method (2), a colored film may be formed using a coating material containing two or more kinds of colored particles having different color tones so that two or more colored areas are mixed. According to the method (2), a colored coating in which two or more colored regions are mixed can be formed by one coating. As the colored particles, those that are flat in the colored coating are suitable.

Specifically, as the coating material in the above (2),
-A coating material in which non-film-forming colored particles are dispersed in a dispersion medium containing a binder, and a coating material in which film-forming colored particles are dispersed in a dispersion medium. The shape of each colored region when the colored coating is viewed from the front depends on the shape of the colored particles after coating, and examples thereof include a circular shape, an elliptical shape, and an irregular shape.

  The colored particles in the coating material (2) are preferably gel or liquid. Such colored particles can be obtained by gelling or encapsulating a colorant containing a binder and a color pigment. As the non-film-forming colored particles, gel-like colored particles in which a coloring material is gelled can be used, and as the film-forming colored particles, capsule-like colored particles enclosing a liquid coloring material can be used. . As the binder and the coloring pigment, those similar to the above (1) can be used. As a method of gelling or encapsulating the coloring material, a known method may be employed.

In the coating of the coating material in the above (2), for example, a known applicator such as a spray or a roller can be used. The coating amount of such a covering material is preferably about 50 to 800 g / m ^{2 in} terms of solid content, although it depends on the form of the covering material. At the time of coating, a diluent such as water can be mixed to appropriately adjust the viscosity. The coating material is usually dried at room temperature.

In the second step of the present invention, a coating material containing a binder capable of forming a transparent film and a fading dye is applied onto the above-described colored film.
In this invention, in this 2nd process, the coating state of a coating liquid can be confirmed with the color tone of a fading pigment. And after a coating liquid forms a film, a fading pigment | dye fades with time by the influence of light etc., and a film changes to a colorless and transparent thing. Thereby, the transparent film which protects a colored film and does not inhibit the aesthetics of a colored film is formed.

  As the coating liquid in the second step, any coating material may be used as long as it contains a binder capable of forming a transparent film and a fading dye. It is suitable.

  As the binding material in the coating liquid, any material that can form a transparent film may be used. For example, an acrylic resin, a urethane resin, an epoxy resin, a vinyl acetate resin, a silicon resin, a fluororesin, an acrylic vinyl acetate resin, an acrylic urethane resin, An acrylic silicon resin etc. are mentioned. These can be used alone or in combination of two or more. As such a binder, aqueous resins such as water-dispersible resins (resin emulsions) and water-soluble resins are particularly suitable.

The fading dye is a dye that fades with time due to an external stimulus such as light, pH, temperature, etc. (preferably light).
Examples of the fading dye include at least one selected from a halogen group, a sulfuric acid group, a hydrogen sulfate group, a nitric acid group, a phosphoric acid group, a hydrogen phosphate group, a carbonic acid group, a hydrogen carbonate group, and a carboxylic acid group in the compound. Those containing an anionic group of Such a fading dye can be easily dissolved in an aqueous medium by the action of ionic dissociation.
Specific examples of the fading dye include food dyes such as food blue No. 1, food red No. 3, food red No. 102, food red No. 104, food red No. 105, food red No. 106, food green No. 3, etc. Is mentioned.
The concentration of the fading dye in the coating solution is preferably 0.01 to 100 mg / L, more preferably 0.05 to 80 mg / L. If the concentration of the fading dye is within such a range, the color tone of the dye before fading is easily visible, and the time required for fading can be shortened.

  The aqueous medium contains water as a main component, and a water-soluble compound such as a lower alcohol, a polyhydric alcohol, and an alkylene oxide-containing compound may be mixed as necessary. The ratio of water in the aqueous medium is preferably 50% by weight or more, more preferably 70% by weight or more.

  The coating liquid in the second step desirably contains a metal ion in addition to the above components. Thereby, fading of a fading pigment can be further accelerated, and a transparent film can be obtained at an early stage. The reason why such an effect occurs is not clear, but when an anionic group is contained in the fading dye, it is considered that the metal ion and the anionic group cause some kind of interaction to promote the fading of the dye. .

  The concentration of metal ions in the coating solution is preferably 1-1000 mg / L, more preferably 10-800 mg / L. If the concentration of the metal ion is within such a range, the color fading of the dye can be accelerated without significantly affecting the physical properties of the film. In addition, the density | concentration of a metal ion is a weight conversion of the metal ion (mol / L) contained in 1 liter of aqueous media, and can be measured with a well-known measuring method.

The metal ion becomes a metal ion in an aqueous medium, and contains one or more metal elements selected from Group 1 elements, Group 2 elements, and transition elements.
Examples of the Group 1 element include lithium, sodium, potassium, and rubidium. Examples of the Group 2 element include beryllium, magnesium, calcium, strontium, and barium. Transition elements are metal elements belonging to Group 3 elements to Group 11 elements in the periodic table, and examples thereof include titanium, vanadium, manganese, iron, cobalt, nickel, copper, yttrium, zirconium, and silver.
In particular, when the fading dye has a monovalent anion group such as a halogen group, a carboxylic acid group, or a sulfate group, a metal containing a divalent or higher valent metal element selected from Group 2 elements and transition elements as a metal ion Ions are preferred. Furthermore, from the viewpoint of safety and the like, a metal ion containing a metal element of Group 2 element is more preferable.

  The coating liquid in the second step can further contain components other than those described above. Examples of such components include inorganic particles, thickeners, leveling agents, wetting agents, plasticizers, film-forming aids, antifreezing agents, pH adjusting agents, preservatives, antifungal agents, anti-algae agents, and antibacterial agents. Agents, dispersants, antifoaming agents, ultraviolet absorbers, antioxidants, catalysts, photocatalysts, crosslinking agents, fibers and the like. In addition, the coating liquid can be colored with a colorant (dye, pigment, etc.) other than the fading dye, as long as the effects of the present invention are not impaired. The solid content of the coating liquid is preferably 20% by weight or less, more preferably 0.1% by weight or more and 10% by weight or less.

Among the above components, as the inorganic particles, in particular, manganese, iron, cobalt, nickel, copper, zinc, silver, platinum, gold, silicon having an average primary particle diameter of 1 nm to 200 nm (preferably 3 nm to 100 nm), Inorganic particles containing metal elements such as germanium and tin are preferred. Such inorganic particles have transparency in the range of the above particle diameter, and also have an effect of further fading the fading of the fading dye.
As such inorganic particles, those containing silicon element are particularly preferable. Examples of inorganic particles containing silicon element include silica sol. These can be produced using sodium silicate and a silicate compound as raw materials, and may be of an acidic type to basic type (preferably, neutral type to basic type), or may have been subjected to some surface treatment.

In the second step, a coating liquid containing the above components may be applied to the entire surface of the colored film. As a coating instrument, well-known things, such as a brush, a roller, and a spray, can be used, for example. Coating with the amount of the coating material for forming the transparent coating film, in terms of solid content, preferably 0.1 to 50 g / ^{m 2,} more preferably 0.5 to 20 g / ^{m 2.} The coating solution may be usually dried at room temperature.

  Examples are given below to clarify the features of the present invention.

(Colored coating material)
As a colored coating material, an acrylic resin emulsion paint colored in each color tone shown in Table 1 was prepared.

(Coating liquid for transparent film)
In the formulation shown in Table 2, the following resin, fading dye, and medium were mixed to prepare a coating liquid for transparent film.
Resin A: acrylic silicon emulsion (composition: 2-ethylhexyl acrylate, methyl methacrylate, styrene, γ-methacryloyloxypropyltrimethoxysilane, cyclohexyl methacrylate, methacrylic acid), solid content 45 wt%, medium: pure water (metal ion 0 mg / L)
-Fading dye A: Edible red No. 3 (erythrosine, anionic group: iodo group, carboxylic acid group)
-Fading dye B: Food blue No. 1 (Frillant blue FCF, anionic group: sulfonic acid group)
-Fading dye C: Food red No. 104 (Phloxine, anion group: chloro group, bromo group, carboxylic acid group)
Medium A: pure water (metal ion 0 mg / L)
In addition, sodium chloride (monovalent metal ion), calcium chloride (divalent metal ion), aluminum sulfate (trivalent metal ion), etc. are mixed in medium A so that the metal ion concentrations shown in Table 2 are obtained. Prepared.

<Test I>
A ceramic siding boat was prepared as a base material. This ceramic siding board has a tile-like uneven pattern on the surface.
The first colored coating material is spray-coated on the entire surface of the base material at a coating amount of 80 g / m ² (solid content), dried for 3 hours, and then the second colored coating material is applied only to the convex portions of the tile-like uneven pattern. Was coated with a roller at a coating amount of 80 g / m ² (solid content) to form a colored film. Next, after curing for 1 day, the coating solution for transparent film was spray-coated at a coating amount of 3 g / m ² (solid content). The coating and curing were all performed under standard conditions (temperature 23 ° C., relative humidity 50%).
Here, the coating workability of the coating liquid for transparent film was evaluated. The evaluation criteria were performed in three stages (A>B> C) where “A” was the one where it was easy to confirm the painted location and “C” was the one where it was difficult to confirm the painted location.
Table 3 shows the combinations of the colored coating materials and the coating solutions for transparent coating, and the evaluation results. In Test Examples 1 to 20, good results were obtained.

<Test II>
The test plate obtained in the above test I was allowed to stand for 48 hours inside the north indoor window (air temperature 25 ° C.) where it was not exposed to direct sunlight, and the surface color immediately after coating and after standing for 48 hours was evaluated. The evaluation criteria were three stages (A>B> C) where “A” indicates that the color of the fading dye has disappeared and “C” indicates that the color of the fading dye remains. The evaluation results are shown in Table 3.

Claims (3)

A film forming method for protecting a colored film with a transparent film,
A first step of forming a colored coating on the ground;
A second step of applying a coating solution containing a binder capable of forming a transparent coating, a fading dye, an aqueous medium, and metal ions on the colored coating;
The fading dye has a monovalent anionic group selected from a halogen group, a carboxylic acid group, and a sulfuric acid group,
The metal ion is a metal ion containing a divalent or higher valent metal element selected from Group 2 elements ;
The colored film in the first step is a mixture of two or more colored regions, and at least one color of the colored region has an L ^* value of 80 or more, an a ^* value of −3 to 3, and a b ^* value of A method of forming a film, characterized in that the film is colored so that the color tone before fading of the fading dye in the second step is visible.   2. The film forming method according to claim 1, wherein the concentration of metal ions in the coating solution (concentration of metal ions contained in 1 liter of aqueous medium) is 1-1000 mg / L. 2. At least one color of the colored region has an L ^* value of 85 or more, an a ^* value of −2.5 to 2.5, and a b ^* value of −2.5 to 13. Or the film formation method of Claim 2.