Coating method

Abstract

To provide a coating method capable of stably and easily forming a mottled pattern on an object to be coated and forming a coated surface excellent in design.SOLUTION: An excellent design can be easily formed by applying coating material only to a projecting portion of a coating device having an uneven coating material holding layer before the coating material of a coating material layer having 50 to 3000 μm thickness is dried and forming a mottled pattern on a surface to be coated with the coating device.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a coating method that can form a coated surface that is excellent in design. [Background technology]

[0002] BACKGROUND ART Conventionally, painting of structures such as buildings has been carried out by spray painting using a spray gun or roller painting using a painting roller. Spray painting using a spray gun or similar device is a painting method that can paint relatively quickly and form a uniform coating. It is also a painting method that can create a painted surface with excellent design by using paints such as multi-color spraying or multi-color paints that apply multiple colors of paint at once.

[0003] However, this practice is on the decline due to the many preparations required before painting, such as curing, and problems such as paint splashing into the surrounding area. On the other hand, roller painting using a paint roller is slightly slower than spray painting, but it is a painting method that is often used to paint buildings and other structures because there is less splatter during painting. However, it has been difficult to create decorative patterns such as mottled patterns.

[0004] However, among the coating methods using coating rollers, Patent Document 1 describes a coating method in which a fibrous roller is used to easily obtain a spotted pattern. This is a coating method in which a colored paint is applied to a substrate using a fiber roller. When the fiber roller is dried, the thickness of the fiber layer is 2 mm to 15 mm, the fiber thickness is 5 μm to 150 μm, and the viscosity is 1 Pa·s to 50 Pa·s. The colored paint is applied to the fiber layer at a rate of 0.001 g / cm per unit area. 2 More than 0.5g / cm 2 The next step is to use a fibrous roller impregnated with the following to create a speckled pattern.

[0005] Patent Document 2 describes a painting roller that is highly productive and can easily form various mottled patterns. This painting roller has a roller body with a paint adhesion layer on its outer circumferential surface and a cylindrical member that covers the roller body, with the cylindrical member having multiple through-holes in its peripheral wall through which the paint adhesion layer protrudes to form brush portions. This painting roller allows a mottled pattern to be formed simply by covering the roller body with a cylindrical member having multiple through holes, making it possible to produce painting with excellent design even when painting with a roller. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-016127 [Patent Document 2] Japanese Patent Application Laid-Open No. 2017-056439 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in Patent Document 1, it is difficult to adjust the amount of paint impregnated in the fiber roller, and therefore it is sometimes not possible to form a spotted pattern. Furthermore, in Patent Document 2, it is necessary to prepare a cylindrical part with multiple through holes and then cover the roller body with it, which is time-consuming. Also, paint may get on the cylindrical part, making it impossible to form the desired pattern.

[0008] The present invention provides a coating method that can stably and easily create a mottled pattern on an object to be coated, thereby forming a coated surface with excellent design. [Means for solving the problem]

[0009] Before the paint in the 50 to 3000 μm thick paint layer dries, the paint is applied only to the convex parts of the coating tool having an uneven paint-retaining layer, and a mottled pattern is created on the surface to be coated with the coating tool, thereby easily creating an excellent design. By making the height of the projections of the coating tool uneven, a mottled pattern can be formed, and a more excellent design can be easily formed.

[0010] By using a natural sponge roller as the coating tool, it is possible to apply a complex mottled pattern, and more excellent designs can be easily formed. The mottled pattern created by the above coating method covers an area of ​​10 to 30% of the surface to be coated, thereby giving the surface an excellent design. DETAILED DESCRIPTION OF THE INVENTION

[0011] An embodiment of the present invention will be described. The coating method of the present invention involves applying paint only to the convex parts of a coating tool having an uneven paint-retaining layer before the paint of a 50 to 3000 μm thick coating layer dries, and using the coating tool to create a mottled pattern on the surface to be coated.

[0012] First, the paint used in the coating method of the present invention is the same as that used in general coating work, and is mainly composed of a binder component such as an organic binder like synthetic resin or an inorganic binder like cement. There are also paints that are a mixture of an organic binder and an inorganic binder. Synthetic resins that are organic binders include acrylic resin, silicone resin, acrylic silicone resin, fluororesin, polyurethane resin, styrene resin, epoxy resin, melamine resin, alkyd resin, vinyl chloride resin, vinyl acetate resin, polyester resin, polyether resin, phenolic resin, and ketone resin.

[0013] These synthetic resins are often dispersed in water to form synthetic resin emulsions, which are water-based paints that use water as a solvent and are therefore preferred for their ease of handling and workability. These synthetic resins may be used alone or in combination of two or more. The monomers constituting these resins are generally used alone or in copolymer form.

[0014] Among the synthetic resin emulsions using these synthetic resins, acrylic synthetic resin emulsions, acrylic styrene synthetic resin emulsions, acrylic silicone synthetic resin emulsions, urethane synthetic resin emulsions, and the like, which have good water resistance, are preferably used. These synthetic resin emulsions are also suitable for use in terms of their water resistance, paint suitability, coating film properties, and ease of availability.

[0015] Inorganic binder cement includes Portland cement, blast furnace cement, alumina cement, jet cement, white cement, etc. Other inorganic binders include gypsum, hydrated lime, dolomite plaster, silicates, colloidal silica, and other silica-based binders. In addition to these binders, paints are made up of a mixture of pigment components such as coloring pigments and extender pigments, filler components such as bulking materials and matting agents, fibers, surfactants such as wetting agents, dispersants, and antifoaming agents, high-boiling point solvents such as film-forming agents, antifreeze agents, and plasticizers, viscosity adjusters such as thickeners, pH adjusters, preservatives, antifungal agents, anti-algae agents, antibacterial agents, adsorbents, UV absorbers, antioxidants, and additives such as light stabilizers.

[0016] The viscosity of the coating material used in the coating method of the present invention is preferably in the range of 0.1 to 10.0 Pa·s. This viscosity is measured using a Brookfield viscometer under the following measurement conditions: 23°C, 20 rpm, and 60 seconds. If the viscosity of the paint is lower than 0.1 Pa·s, it is difficult to form a paint layer with a thickness of 50 to 500 μm, as described below.

[0017] If the viscosity of the paint is higher than 10.0 Pa·s, it may be difficult to form a paint layer of uniform thickness. It may also be difficult to apply the appropriate amount of paint to the painting equipment, making it difficult for the paint to adhere to the surface to be painted. This may require multiple applications of the paint to the painting equipment, making it difficult to achieve a stable coating. More preferably, the viscosity of the paint is in the range of 0.3 to 7.0 Pa·s. Within this range, a paint layer of uniform thickness can be easily formed, and a pattern with excellent design can be stably formed.

[0018] The paint used in the coating method of the present invention preferably has a Ti value in the range of 1 to 7. The Ti value indicates the thixotropy, which is the viscosity of the paint, and is calculated using a Brookfield viscometer to determine the ratio of apparent viscosities at two different rotational speeds. The formula for calculating the Ti value is shown below. Ti value = viscosity at low rotation speed / viscosity at 10 times higher rotation speed The measurement conditions were 23°C and the measurement was taken after rotating for 60 seconds. When the Ti value is 1, the paint is a Newtonian fluid, and as the value increases above 1, the degree of thixotropy increases.

[0019] With the Ti value in this range, the paint layer tends to be uniform in thickness, and the paint is easily applied only to the convex parts of the coating equipment with an uneven paint holding layer. In addition, there is little dripping of the paint when applied to the surface to be coated, the flatness of the coating film is not impaired, and the storage stability of the paint is good. The Ti value is more preferably in the range of 1 to 5, and within this range, the paint layer tends to have a more uniform thickness.

[0020] The coating tool used in the coating method of the present invention has an uneven paint-retaining layer. By having an uneven paint-retaining layer, paint can be applied only to the convex parts, and by applying paint only to the convex parts, it is easy to create a mottled pattern on the surface to be coated. The height of the convex portions is preferably non-uniform. By making the height of the convex portions non-uniform, a mottled pattern can be randomly formed on the surface to be coated, and a pattern with excellent design can be stably formed.

[0021] It is also preferable that the size of the convex portions is non-uniform. By making the convex portions non-uniform in size, a more non-uniform mottled pattern can be imparted to the surface to be coated, and a pattern with greater depth and excellent design can be stably formed. The material for the paint retention layer of painting equipment can be anything that can hold paint, including fibers, sponges, and chip urethane, which is made by crushing urethane foam with different physical properties such as absorbency and hardness, blending it with adhesive, and then putting it into a mold and pressing it into place.

[0022] The type of coating tool is not particularly limited as long as it has an uneven paint-retaining layer, but a roller-shaped coating tool is preferred. By using a roller as the coating tool, coating workability is improved and a mottled pattern can be easily created. Paint rollers with an uneven paint retention layer include pattern rollers, which are porous rollers with an uneven pattern applied, wool rollers with uneven fibers of different lengths, and rollers with sponge or chip urethane sparsely attached to the core material.

[0023] Of these, it is preferable to use a natural sponge roller. A natural sponge roller has a coating-retaining layer with irregular heights and sizes, which allows it to create an uneven mottled pattern when applied to the surface to be coated, and it is possible to stably form a pattern with excellent design. Furthermore, natural sponges have a moderate flexibility, so even if the surface to be coated is uneven, they can penetrate into the recesses and create patterns even in the recesses of the surface to be coated.

[0024] The coating method of the present invention uses the above coating material and coating equipment to create a mottled pattern. A specific coating method is described below. First, a paint layer having a thickness of 50 to 3000 μm is prepared using the above paint. By setting the thickness of the paint layer in the range of 50 to 3000 μm, it becomes easy to apply the paint only to the convex portions of the uneven paint holding layer.

[0025] If the paint layer is less than 50 μm thick, only a small amount of paint will adhere to the painting tool, and the paint will not adhere to the surface, narrowing the area that can be painted and making work difficult.If it is more than 3000 μm thick, the paint may adhere to the recesses of the uneven paint retention layer, making it impossible to create a mottled pattern. The thickness of the paint layer is preferably in the range of 50 to 500 μm, and by being in this range, an appropriate amount of paint can be applied only to the convex portions of the uneven paint holding layer.

[0026] The width of the paint layer is not particularly limited, but it is preferably equal to or greater than the width of the applicator. If it is smaller than the width of the applicator, the width of the paint applied to the applicator will be small, and the width of the paint applied to the surface to be painted will also be small, resulting in poor workability. There are no particular restrictions on the substrate used to create this paint layer, but it is best to use a material that does not easily absorb the paint, as if the material were to easily absorb the paint, the paint would be absorbed into the substrate and the thickness of the paint layer would not be stable.

[0027] A paint layer is created by placing paint on such a substrate. There are no particular restrictions on the method for creating the paint layer, as long as it is a paint layer with a thickness of 50 to 3000 μm, and methods include moving the substrate on which the paint is placed to spread the paint, spreading the paint using a roller, spreading the paint using a bar coater or applicator, and creating a paint layer by adjusting the amount of paint and pouring it into a container so that it reaches the specified thickness. Before the paint layer thus prepared dries, paint is applied only to the convex portions of a coating tool having an uneven paint-retaining layer, and a mottled pattern is formed on the surface to be coated using the coating tool.

[0028] The coating substrates on which the mottled pattern can be formed using the coating method of the present invention include mortar, concrete, ALC panels, extruded boards, siding boards, calcium silicate boards, gypsum boards, fiber-reinforced cement boards, lightweight cement boards, etc., which contain inorganic components such as cement. Other examples include metal products such as steel, iron plates, and metal siding, as well as tiles, glass, stone, wood, and plastic products, some of which may have a coating film formed on them.

[0029] These coating substrates are used as the surface to be coated, and the coating is applied only to the convex parts of a coating tool having the uneven coating holding layer on the coating layer, and the coating tool is used to hit the surface to be coated, or if the coating tool is a roller, to roll the coating tool to apply the paint to the surface to be coated, thereby creating a mottled pattern. At this time, the size of the mottled pattern can be changed by varying the force with which the paint-retaining layer is pressed against the surface to be coated.

[0030] The mottled pattern preferably occupies an area in the range of 10 to 30% of the surface to be coated. By having the mottled pattern occupy an area in the range of 10 to 30% of the surface to be coated, the pattern will have excellent design appeal. Furthermore, when the paint is applied in layers, each color can be recognized, creating a design with depth.

[0031] Before applying this mottled pattern, a paint may be applied to the base to form a coating film, which can then be used as the surface to be painted. If you want to make the most of the color and design of the base, a clear paint is preferred. This clear paint may contain a sealer to improve adhesion and prevent uneven absorption, or a water repellent to prevent wet skin when the surface to be painted is mortar or concrete.

[0032] Enamel paint is preferred when hiding the color or design of the paint base. This enamel paint is the same as the paint used to create patterns, and it is preferable that it has a hiding rate of 90% or more. If the hiding rate is less than 90%, the underlying material may show through and the desired design may not be achieved. A hiding rate of 95% or more is more preferable, allowing the desired design to be achieved without the underlying material showing through.

[0033] In this way, a paint can be applied to a paint base to form a coating film, which can be used as the surface to be painted, but it is preferable that the paint used to form the mottled pattern be a different color from the surface to be painted.If the surface to be painted and the paint used to form the mottled pattern are the same color, the pattern formed will not stand out, and the design will not be good. More preferably, the color difference ΔE between the surface to be coated and the paint used to form the pattern is 1 or more, and even more preferably, the color difference ΔE is 2 or more. If the color difference ΔE is less than 1, it is difficult to visually distinguish the difference in color tone. If ΔE is 2 or more, the difference in color tone can be expressed, resulting in a texture and feel with excellent design properties.

[0034] Furthermore, after forming a mottled pattern on the surface to be coated, paint of a different color can be applied in the same manner as above. By applying paint of different colors and forming coating films of different colors, it is possible to form a complex pattern, which allows the formation of a pattern with better design. This painting method allows multiple coats to be applied, but it is preferable that the paint film area of ​​one color does not become smaller than 10% of the surface to be painted. If the paint film area of ​​one color is smaller than 10% of the surface to be painted, the mottled pattern may become too fine and the design may become poor.

[0035] After forming a pattern on the surface to be painted in this way, a clear coating can be applied to the entire surface. Applying a clear coating protects the pattern, improving weather resistance and stain resistance, and allowing the pattern to be maintained for a long period of time. The coating method of the present invention configured by these will be explained in more detail with reference to an embodiment.

[0036] Example 1 A flexible board was used as the base for painting, and an acrylic synthetic resin emulsion sealer was applied as a primer coat over the entire surface using a wool roller with a 13mm bristle length, which is used for applying general paint, and then dried.After this, Paint A was applied over the entire surface using the same wool roller as the primer coat, and then dried to prepare the surface to be painted. Paint A is an acrylic silicone synthetic resin emulsion paint with a Munsell color value of 5.6YR4.2 / 2.3, a viscosity of 5.1 Pa·s measured with a B-type viscometer (23°C, 20 rpm, 60 seconds), and a Ti value of 3.5.

[0037] Next, paint B, which has a different color tone from paint A, was placed on a 30 cm square trowel and spread onto the trowel with a wool roller to create a paint layer. The thickness of this paint layer was measured to be approximately 300 μm. Paint B is an acrylic silicone synthetic resin emulsion paint with a Munsell color value of 5.4YR3.8 / 0.8, a viscosity of 5.3 Pa·s measured with a B-type viscometer (23°C, 20 rpm, 60 seconds), and a Ti value of 3.5.

[0038] Before this paint layer dried, a sponge roller was rolled over the paint layer to apply Paint B. When the roller was checked, Paint B was found to have been applied only to the convex parts of the uneven paint-retaining layer. When this roller was rolled over the surface to be coated prepared above and paint B was applied, a mottled pattern was formed over approximately 20% of the surface, resulting in an excellent design.

[0039] Example 2 Painting was carried out in the same manner as in Example 1, except that the roller used to apply Paint B was changed to a natural sponge roller. The use of a natural sponge roller resulted in an irregular mottled pattern, giving the paint film an aged appearance. The sponge roller used in Example 1 had a relatively uniform uneven pattern, and the height of the convex parts was also roughly the same, which resulted in a uniform and unnatural mottled pattern. However, the natural sponge roller had an uneven pattern of the uneven paint retention layer and an uneven height of the convex parts, which resulted in an irregular mottled pattern, which is thought to have resulted in an excellent design.

[0040] Example 3 On the surface painted in Example 2, a metallic paint was spread on a trowel in the same manner as in the painting method for Paint B above to create a paint layer, and then painted using a natural sponge roller. A mottled pattern of metallic paint was applied to approximately 20% of the painted surface, and the colors of Paint A and Paint B could be recognized, resulting in a rusty metal finish.

[0041] Example 4 The coating was carried out in the same manner as in Example 2, except that a siding board was used as the coating base. The siding board used was a single color with a textured border pattern, but by painting it using the above method, it was given a mottled pattern with excellent shading and design. In addition, the moderate flexibility of the natural sponge roller made it possible to paint even the recessed areas.

[0042] (Comparative Example 1) The paint layer of Paint B was prepared in the same manner as in Example 2, except that Paint B was placed in a roller bucket used in normal roller painting in the same manner as normal roller painting, and the paint layer was prepared. The thickness of the paint layer in this case was approximately 3 cm. When painting using this method, paint B was applied to the entire paint-retaining layer of the natural sponge roller, and the paint was applied to almost the entire surface, resulting in a uniform design rather than a mottled pattern.

[0043] (Comparative Example 2) The coating was carried out in the same manner as in Example 1, except that the roller used to apply paint B was changed to a wool roller with a bristle length of 13 mm, which is used in applying a general topcoat paint, similar to the roller used to apply paint A. When painting using this method, only a small amount of paint adheres to the wool roller and it quickly fades, making it difficult to work with, and because the wool roller has no unevenness, no mottled pattern is left, resulting in a less than desirable design.

Claims

1. This coating method involves applying paint only to the convex parts of a coating tool having an uneven paint-retaining layer before the paint of a 50 to 3000 μm thick coating layer dries, and using the coating tool to create a mottled pattern on the surface to be coated.

2. 2. The coating method according to claim 1, wherein the height of the projections of the coating tool is not uniform.

3. 2. The coating method according to claim 1, wherein the coating tool is a natural sponge roller.

4. The coating method according to any one of claims 1 to 3, wherein the mottled pattern occupies an area ranging from 10 to 30% of the surface to be coated.