JPH06207133A - Method for coloring porous material - Google Patents

Abstract

PURPOSE:To provide a coloring method, excellent in drying properties, prevention of bleeding of a colorant to a transparent film and pollution and resource saving and useful for coloring a surface porous part of a woody material, etc., by using a water-based colored stain containing a color pigment, etc., dispersed therein. CONSTITUTION:Hole parts of a material having a porous part on the surface such as wood are colored. In the process, a water-based colored stain prepared by dispersing a color pigment or a dye is used to color the hole parts. The water-based colored stain is a composition, etc., obtained by mixing and dispersing an aqueous resin such as an acrylic resin, a urethane resin, PVA resin or an unsaturated resin and a dye in water and, as necessary, blending a monomer having an unsaturated group polymerizable by irradiation with ultraviolet rays, a photosensitizer, etc., therein.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of coloring mainly a hole portion of a porous material having a porous portion on at least the surface thereof such as a wooden material.

[0002]

2. Description of the Related Art Conventionally, in order to make the best use of the natural texture and the natural texture of wood, the color of the conduit surface (wood, perforated part) is filled with a coloring agent. Then, there are many methods of applying transparent paint over the entire surface. Up to now, an organic solvent-based colorant having an organic solvent as a solvent or a dispersion medium has been used as the colorant, but it is not preferable from the viewpoint of pollution prevention, resource saving and danger prevention, and further, the filled colorant is dried. It takes a long time (generally several hours or more at room temperature) to cure,
The colorant has defects such as migration to a transparent coating film and bleeding easily, and elimination of these defects is strongly desired.

[0003]

DISCLOSURE OF THE INVENTION The present invention is to eliminate the above-mentioned defects in coloring the pores of a porous material,
The characteristic is that an aqueous coloring stain in which a coloring pigment or dye is dispersed is used as a coloring agent. As a result, all of the above defects due to the use of the organic solvent were eliminated, the curing time could be shortened, and the transfer of the coloring agent to the transparent coating film could be prevented.

That is, according to the present invention, in coloring (painting) mainly the pores of a material having a porous portion on its surface,
The present invention relates to a method for coloring a porous material, which comprises using an aqueous colored stain in which a color pigment or a dye is dispersed as a colorant.

The porous material (object to be coated) applicable in the present invention has only to have at least its surface porous, and it does not matter whether the inside is porous or not. The diameter of the pores in the porous portion is not particularly limited, but is preferably about 5 mm or less, particularly preferably about 1 mm or less. Examples of such porous materials include slate, concrete blocks, cement products, and other inorganic materials and foamed plastic materials, in addition to the above wood materials. These shapes are not particularly limited and include, for example, a rod shape, a plate shape, a sheet shape, a polygonal shape,
Examples include curved surfaces and combinations thereof. In addition, it does not matter if the surface has irregularities such as grooves. In the present invention, it is preferable to polish or surface-treat the surfaces of these materials before coating the colorant. In particular, the method of the present invention is preferably applied to wood used for building materials, furniture furnishings, ornaments, and the like.

The aqueous colored stain used in the present invention is a dispersion of a coloring pigment or dye, and more specifically, it is obtained by mixing and dispersing an aqueous resin and a coloring pigment or dye in water. According to the above, a composition in which a monomer having an unsaturated group which is polymerized by irradiation of ultraviolet rays is blended can also be applied. Further, an organic solvent may be added to this aqueous colored stain within a range that does not impair the object of the present invention. Each of these components will be described below.

As the water-based resin, a coating resin known per se which may or may not have a hydrophilic group (eg, carboxyl group, amino group, etc.) in the resin skeleton can be used. Specifically, acrylic resin, urethane resin,
Examples thereof include those having a basic skeleton such as polyester resin, epoxy resin, vinyl acetate resin and polyvinyl alcohol resin, and further, unsaturated resins obtained by introducing a polymerizable unsaturated double bond into these resins are also included. The introduction of the polymerizable unsaturated double bond can be performed by a known method. Of these, the resin having a hydrophilic group can be dissolved or dispersed in water as it is, but the resin having no hydrophilic group can be dispersed in water by adding an emulsifier or the like. These resins include those that can be cured at room temperature or by heating, or that can be cured by ultraviolet irradiation. A cross-linking agent can be used in combination to cross-link and cure the above resin. Specifically, a melamine resin (including an alkyl ether compound) or a block polyisocyanate compound can be used as a room temperature or heat curable resin, and a UV curable resin can be used. A monomer having a polymerizable unsaturated double bond and the like are preferable. Further, as the coloring pigment or dye, those known as a coloring agent for paint can be applied.

In the method of the present invention, the use of the ultraviolet radiation curable type among the above aqueous colored stains is preferable because shortening of the curing time and prevention of migration of the colorant are remarkably excellent.

The ultraviolet irradiation-curable aqueous colored stain comprises a resin having a polymerizable unsaturated double bond, a monomer having a polymerizable unsaturated double bond, a photosensitizer and a coloring pigment or dye dispersed in water. Alternatively, the main component is the one obtained by melting.

The resin having a polymerizable unsaturated double bond is, for example, an unsaturated polyester resin; polyester resin or acrylic resin with (meth) acrylic acid or hydroxyalkyl (meth) acrylate directly or through a polyisocyanate or the like. An unsaturated resin obtained by introducing a polymerizable unsaturated double bond into the terminal or side chain by addition of (meth) acrylic acid or hydroxyalkyl (meth) acrylate to urethane-modified acrylic resin or polyester resin An unsaturated resin obtained by introducing a polymerizable unsaturated double bond into the terminal or side chain; an unsaturated resin obtained by introducing a polymerizable unsaturated double bond into the terminal or side chain of an epoxy resin: To be The number average molecular weight of these resins is preferably in the range of about 1,000 to 100,000, and the polymerizable unsaturated double bond has 2 in 1 molecule.
More than one is suitable.

Further, the monomer having a polymerizable unsaturated double bond is a compound having one or more polymerizable unsaturated double bonds in one molecule and having a molecular weight of less than 1,000. Preferred are (meth) acrylic acid ester, styrene, vinyl acetate, (meth) acrylonitrile, glycidyl (meth) acrylate and the like. Furthermore, 2 per molecule obtained by reacting (meth) acrylic acid with a polyhydric alcohol such as ethylene glycol, polyethylene glycol, propylene glycol or polypropylene glycol.
A monomer having at least one polymerizable unsaturated double bond can also be preferably used.

Examples of the photosensitizer include benzoin, benzoin alkyl ethers, 2-methylbenzoin,
Examples thereof include benzophenone, Michler's ketone, benzyl, benzyl dimethyl ketal, anthraquinone, methyl anthraquinone, diacetylacetophenone, diphenyl sulfide and anthracene.

The composition ratio of each of the above components in the ultraviolet radiation curable aqueous colored stain can be arbitrarily selected according to the purpose. For example, a resin having a polymerizable unsaturated double bond and a monomer having a polymerizable unsaturated double bond can be selected. Based on the total weight of both components, the ratio to the monomer is 10 to 90% by weight for the former and 9 for the latter.
0 to 10% by weight is preferable, and the photosensitizer contains 100 parts of both components.
0.1 to 10 parts by weight is preferable per part by weight.

The ultraviolet irradiation method for curing the porous portion filled with the ultraviolet irradiation curable aqueous colored stain is, for example, a mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, a carbon arc, a metal halide lamp, or a sun. When light is used as an irradiation source and the irradiation with ultraviolet rays is usually 10 to 2,000 mJ / cm ² in air or an inert gas, the colored stains filled in the porous portion are rapidly crosslinked and cured, The object of the invention can be achieved.

The aqueous colored stain used in the present invention has a viscosity at the time of coating of 7 at Iwata cup / 20 ° C.
~ 30 seconds, especially 7 to 10 seconds, and the solid content is 10
-40% by weight, especially 20-30% by weight are suitable.

In the method of the present invention, the surface of the porous material is coated with the aqueous colored stain, and the aqueous colored stain is mainly filled in the pores of the surface of the material. The beauty of nature and natural flavors are utilized. Specifically, first, the aqueous colored stain is applied to the surface of the porous material by, for example, a natural roll coater, a spray or a shower coater. The coating amount of the aqueous colored stain is, for example, 1 to
10g / (30cm × 30cm), especially 2-5g / (30cm
× 30 cm) is preferred. Then, while wiping the excess aqueous colored stain applied to the surface, the inside of the hole is filled with the aqueous colored stain.

The wiping is to remove the water-based colored stains applied to the parts other than the porous part while filling the water-based colored stains applied to the surface of the porous material into the porous part, and specifically, reverse roll coater and brush wiping. (Wiping machine), manual wiping (wiping with waste cloth), cloth belt wiping, and the like. Then, the filled aqueous colored stain is cured. The curing method can be arbitrarily selected according to the composition of the aqueous colored stain, and it is cured by leaving it at room temperature, heating, or irradiating with ultraviolet rays.

In the present invention, a transparent coating film-forming coating material (clear coat) can be applied to the surface of the porous material, if necessary, after the aqueous colored stain is filled in the porous portion of the surface of the porous material. The clear coat uses an organic solvent and / or water as a solvent or a dispersion medium,
For example, a coating material known per se, which is mainly composed of an acrylic resin, a polyester resin or the like, can be used as a room temperature curable type, a heat curable type, or an ultraviolet irradiation curable type. The coating amount is, for example,
3 to 50 g / (30 cm x 30 cm), especially 4 to 30 g /
(30 cm × 30 cm) is preferable.

[0019]

【The invention's effect】

1. Due to its excellent drying property, intermediate coating or top coating can be performed quickly. 2. The aqueous stain filled in the pores hardly oozes into the intermediate coating film or the top coating film. 3. Since the aqueous stain used in the present invention uses water as a solvent or a dispersion medium, it is preferable from the viewpoints of low risk, pollution prevention and resource saving.

Examples of the present invention will be described below. I. Sample Porous material: Oak (wood) Aqueous colored stain: 80 parts by weight of polyethylene diacrylate (number average molecular weight of about 400 to 800), 20 parts by weight of unsaturated resin emulsion obtained by adding hydroxyethyl acrylate to urethane modified polyester resin ( (As solids), 6 parts by weight of yellow pigment, 4 parts by weight of black pigment, 4 parts by weight of red pigment, 5 parts by weight of photosensitizer, 6 parts by weight of pigment dispersant, 353 parts by weight of tap water. The minute content rate was adjusted to 25% by weight. Paint viscosity is about 7 seconds / Iwata cup / 20 ° C.

II. Example 2-5 g of an aqueous colored stain sprayed onto a porous material
A coating amount of / (30 cm × 30 cm) was applied, the mixture was left at room temperature for several minutes, and then wiped with a reverse roll coater or brush wiping. The aqueous colored stain filled in the porous portion was cured by irradiating with ultraviolet light at room temperature.

III. Performance Test Results Even when the cross-linked curable acrylic resin-based clear coat was applied to the coated plate obtained in the example, no bleeding of the pigment in the colored stain was observed in the clear coat coating film. Furthermore, water resistance (80 ° C warm water / 1 hour and 60 ° C dry /
10 cycles No abnormality: Sunshine weatherometer 250 hours No abnormality: Alkali resistance (1 wt% sodium carbonate 1 cc was dropped, and the coated surface was observed after 6 hours) No abnormality.

Claims (1)

[Claims] 1. A method for coloring a porous material, characterized in that an aqueous colored stain in which a color pigment or a dye is dispersed is used as a colorant for coloring mainly pores of a material having a porous portion on the surface. .