JPS63236569A - Manufacture of multicolor coated board - Google Patents

Abstract

PURPOSE:To form uniformly designed multicolor patterns on porous bases by applying paints for silk screen printing sequentially using screen plates with various specific mesh counts starting with the screen plate having the largest mesh count. CONSTITUTION:Paints are applied for silk screen printing to the surface of a base material 1 as construction material, and the printing is performed using a screen plate with the number of meshes of 100 or less, i.e. a large mesh count to form the primary screen-printed coating 2. This coating is dried and then paints are applied for silk screen printing using a screen plate having the mesh count of 150 or more. Consequently the second screen-printed coating 3 is formed. The second coating 3a paint used may be of the same quality as but of different color from the primary coating 2a paint. As described above, gauzes with different mesh counts are used to enable formation of multicolor patterns which are uniform, sharp and fine.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a method for manufacturing a multicolored pattern coated plate by screen printing, and particularly when applied to a substrate whose surface is porous or has a fine uneven shape. In particular, the present invention relates to a method for producing a suitable multicolored pattern coated plate.

<Prior art> It has been widely adopted to apply multicolored patterns to substrates for building materials, and these methods include printing directly on the substrate using printing means such as gravure, offset, or offset gravure (a) Alternatively, a method (b) is known in which the substrate is printed in a raised manner by screen printing, and then printed on it by a printing means such as gravure, offset, or offset gravure.

<Problems to be Solved by the Invention> However, method (a) is suitable for substrates with smooth substrate surfaces and no absorption of paint, but is suitable for substrates with porous or finely uneven substrate surfaces. When printing on a substrate that has a coating, uneven suction and uneven paint concentration occur, making it impossible to print uniformly. Therefore, the substrate surface must be subjected to complicated ground treatments such as sealing, polishing, and base coat application in advance to ensure a smooth and smooth surface. In addition, there was a problem in that the condition had to be maintained so that no paint was sucked in.

In addition, method (b) can be applied to substrates whose surfaces are porous or have fine irregularities up to the printing process by screen printing, but the height of the screen-printed coating film obtained depends on the surface condition of the substrate. It is difficult to achieve uniformity, and if you print on the coating film in such a state by gravure, offset, offset gravure, etc., uneven paint transfer and uneven paint density will occur due to the difference in printing pressure, so even with this method, the substrate surface There was a problem in that the surface had to be smooth and free of paint absorption.

As a result of intensive studies in view of the above-mentioned problems, the present inventors have found that by combining appropriate screen printing methods, it is possible to eliminate the above-mentioned surface treatment even on substrates whose surfaces are porous or have minute irregularities. The present invention has been achieved by discovering a method for producing a uniform multi-colored pattern coated plate without uneven paint transfer or uneven paint density even if the base treatment is not carried out with precision.

Means for Solving the Problems> That is, the present invention applies a base color coating to a substrate as necessary, and then screen prints the paint using a screen plate having 15 meshes of 100 meshes or less. A versatile method characterized in that a first screen-printed coating is formed, and then a paint is screen-printed on the coating using a screen plate having a mesh number of 150 or more to form a second screen-printed coating. The present invention relates to a method for manufacturing a pattern coated board.

The present invention will be explained in detail below.

Substrates used in the present invention include porous substrates, such as inorganic boards such as concrete, slate, and stone; wood boards such as particle board and hardboard; and various inorganic boards, wood boards, and metal boards with finely uneven surfaces. board,
A representative example is Plastic Saka. It goes without saying that the present invention can be used for substrates with smooth surfaces. Furthermore, porous substrates and substrates with finely uneven surfaces may be sealed, polished, or coated with a base coat as necessary, but they may be completely smoothed as in conventional methods, or completely coated with paint. No suction prevention treatment is required.

In addition, if you want to apply a desired color to the areas where the first screen printing coating is not applied, that is, the exposed surface of the screen plate that is not a pattern element, you may apply a base color coating to the substrate in advance, or use the substrate itself. If you want to use it as it is as part of a pattern element, there is no need to apply a base color coating.

A multicolored pattern is applied onto such a substrate by a screen printing method.

In addition, the screen printing method uses a squeegee to move the paint over a screen plate with an appropriate number of meshes, which hides areas other than the necessary pattern with resin, etc. This is a method in which a raised pattern coating film is formed by rubbing the paint into the surface and then raising the screen plate.

The present inventors created a porous substrate surface using a screen printing method using one coat of sand with a specific mesh number, and even if there were minute irregularities, they could be filled with paint without applying a large load.
Moreover, since the paint surface is on the surface of sand, it was discovered that a uniform coating level could be maintained by scraping with a squeegee. Note that the above effect cannot be obtained no matter what kind of gauze is used; the amount of coating required to fill the pores on the surface of the substrate is required, and the amount of coating depends on the thickness of the threads that make up the gauze. It's decided.

In the present invention, a first screen-printed coating film is formed by screen-printing a paint onto a substrate using a screen plate having a mesh number of 100 meshes or less, that is, a screen plate having large meshes. By using sand having a mesh number within the above range, a smooth coating film can be formed even on a substrate having a porous or finely uneven surface without applying an excessive load.

The lower limit of the number of meshes is not particularly limited, but if it is too small, it will not be possible to express a delicate pattern coating, so a number of meshes of up to about 307 meshes is appropriate.

If the number of meshes exceeds 100 meshes, one squeegeeing operation will cause printing defects or skipping, and the surface of the coating film will not be smooth, which is not preferable.

The paint used can be a paint with a viscosity of about 100 to 400 poise, which has been conventionally used for screen printing. In other words, unsaturated polyester-based, acrylic-based, epoxy-based solvent-free paints, acrylic urethane-based, aminoalkyd-based, urethane-based, epoxy-based solvent-based paints, etc. can be used, but paints with a low solid content lose their diluent when dry. evaporates and the surface of the coating film tends to become uneven, and water-based coatings are not suitable because they have poor leveling.

In particular, in the present invention, after screen printing, quick handling to the next process is possible, and active energy ray-curable paints with a high solids content are desirable, and in particular, ultraviolet-curable paints are relatively easy to apply in terms of equipment. suitable.

An ultraviolet curable paint has an ultraviolet polymerizable compound, a photopolymerization initiator, and a colored pigment as essential components, and further contains extender pigments, solvents, additives, etc. as necessary.

To explain in more detail, the above-mentioned "ultraviolet polymerizable compound"
As the compound, a compound having an unsaturated double bond capable of radical polymerization in the molecule is used. Specifically, relatively low molecular weight polyester resins, alkyd resins, polyether resins, acrylic resins, epoxy resins, urethane resins, silicone resins, polybutadiene resins, acrylic oligomers or prepolymers, and 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, dipropylene glycol mono(meth)acrylate, (meth)acrylamide, N-vinylpyrrolidone, triethylene glycol di(meth)acrylate, trimethylolpropane tri( Representative examples include reactive monomers such as meth)acrylate and dipentaerythritol hexa(meth)acrylate, either alone or in mixtures.

Further, as ultraviolet polymerizable compounds, cationic ring-opening polymerizable vinyl-2-ethylhexyl ether, vinyldecyl ether, 1,2-ethoxycyclohexane, synchropentadiene dioxide, sorbitol polyglycidyl ether, and the like can be used.

In addition, as a "photopolymerization initiator", carbonyl compounds such as benzoin, benzophenone or their esters, benzoyl peroxide, azobisisobutyronitrile,
diphenyldisulfide, N-methyljetanolamine, 2,5-jethoxy-4-(p-)IJruthio)
Representative examples include benzenediazonium hexafluorophosphate and the like. Coloring pigments include titanium oxide, carbon black, zinc white, iron oxide, Bengara, ultramarine blue, and fucrocyanine blue. Extending pigments include silica sand, silicates, talc, kaolin, barium sulfate, calcium carbonate, powder, and fiber. Representative examples include resin powders such as glass, polyurethane, polyester, polyethylene, and polystyrene. Furthermore, typical examples of the "solvent" include doluol, quidylol, acetone, methyl ethyl ketone, ethyl acetate, and the like.

In particular, in the present invention, particle sizes of 30 to 60 μm are added to the paint.
It is preferable that the composition contains 20 to 70% by weight (based on the solid content of the paint) of transparent glass beads.

In other words, by including glass beads, the propagation of light energy into the coating film is carried out smoothly,
Therefore, even if the film is thick, the coating film can be sufficiently cured, and furthermore, the abrasion resistance of the coating film can be improved.

After drying the first screen printed coating, a
The paint is screen printed using a screen plate having a mesh number of 50 or more to form a second screen printed coating.

By using gauze with a mesh number within the above range, even if the surface of the first screen printing coating has some unevenness, it is possible to create a uniform, sharp, finely designed, multi-colored pattern. It becomes possible to form.

There is no particular upper limit to the number of meshes, but if it is too large,
In other words, if the mesh is too small, the paint cannot be rubbed in sufficiently, so a mesh of up to about 350 mesh is appropriate.

It should be noted that if the mesh size is less than 150 meshes, it becomes difficult to form fine patterns, which is not preferable.

Note that if you print on the first screen printing coating by means such as gravure, offset, or offset gravure, there will always be uneven thickness on the substrate, and differences in printing pressure will cause differences in the amount of ink transfer, resulting in color unevenness. This increases the cost and is therefore not suitable for the present invention.

The paint for forming the second screen-printed coating may be the same as the coating for forming the first screen-printed coating, but with a different color.

FIG. 1 shows an example of a multicolored pattern coated plate obtained by the method of the present invention. In the drawings, 1 is a substrate, 2 is a first screen-printed coating, and 3 is a second screen-printed coating.

The multicolored pattern coated plate of the present invention is produced as described above, but if necessary, the entire surface or part of the plate can be overcoated with (color) clear.

<Effects of the Invention> With the method of the present invention, even if the substrate surface is porous and absorbs paint, or if the substrate has a finely uneven surface, it can be coated without the need for surface treatment. Even if the surface is treated, it is possible to produce a sharp, multi-pattern coated plate with excellent design, without completely smoothing it and preventing paint from being sucked in, as in the conventional method, without print omissions, etc.

Furthermore, it is less expensive than methods such as gravure, offset, and offset gravure, and it is easy to change the color or change the appearance.

Hereinafter, the present invention will be explained in more detail with reference to Examples. In the examples, "parts" are expressed on a weight basis.

Example 1 Acrylic urethane resin solvent-based enamel paint (PW) was applied to the surface of a calcium silicate plate with a porous surface and a bulk specific gravity of 0.8
C: 55%, eye poly color) was spray-painted at 80g/m'' to form a base color coating.The base color coating had a finely uneven surface.

Next, on the base color coating film, an ultraviolet curable paint consisting of the following paint formulation 1 [viscosity 250 Poise (Lyon Viscometer)] was scraped off with a 55 degree hardness urethane rubber squeegee and screen printed.

Then 120w/am (including Fe-3n) meta/l
//.

Ultraviolet rays were irradiated for 2 seconds from a distance of 100 mm using a Ride lamp to form a first screen-printed coating film with an average thickness of 200 μm. Then on the first screen printed coating,
A urethane acrylate ultraviolet curable blue paint "A-1 Cure" was applied to a screen covered with 200 mesh plain weave polyester gauze, using a screen plate with a photoengraved floral pattern that matched the 100 mm square tile pattern described above. '' (trade name, manufactured by Nagase Screen Institute) with a urethane rubber squeegee having a hardness of 82 degrees, and screen printing was performed. Next, ultraviolet rays were irradiated for 4 seconds under the above conditions to form a second screen-printed coating film with an average thickness of 10 μm.

Next, apply acrylic urethane resin solvent-based clear paint.
A coated board with a multicolored pattern was produced by spray painting at a rate of 0 g/m'.

The resulting painted board has a clear and fine blue floral pattern printed on a 100 mm square quill pattern on a white background with a smooth surface on the eye-poly-colored joints, giving it a design with a finish similar to that of tiles. It was an expensive painted board.

Paint formulation 1 Acrylic urethane oligomer 22 parts N-vinylpyrrolidone 6 parts Acetophenone photopolymerization initiator 2 Clear soda glass beads (average particle size 30μ) 62 parts' Zinc sulfide pigment 8 parts Example 2 PVC with a beige matte surface Using a screen plate on which a pattern with an abstract flower petal motif was photoengraved on a screen covered with 100-mesh plain weave sand made of polyester on the surface of a steel plate, 0.2 parts of Shinkasha Red pigment was added to the paint formulation 1. Added ultraviolet curing paint [viscosity 250
Poise (Lyon Viscometer)] was scraped off with a 55 degree hardness urethane rubber squeegee and screen printed. Next, ultraviolet rays were irradiated for 3 seconds under the same conditions as in Example 1, and the average film thickness was 10.
A first screen printed coating of 0μ was formed.

Next, on top of the first screen-printed coating, several petals matched to the above-mentioned hole pattern were placed on a screen made of 300-mesh plain weave polyester gauze to give gradation by changing the density of the halftone dots. Using a photolithographic screen plate, screen print the air-drying vinyl resin red paint "Vinate" (trade name, manufactured by Nagase Screen Institute) using a urethane rubber squeegee with a hardness of 82 degrees, dry at room temperature,
A second screen printed coating was formed with an average thickness of 5 microns.

The resulting painted board had a smooth pink petal pattern with a few petals in soft gradations of red on a beige pear surface, and was highly decorative.

Comparative Example 1 A coated plate was produced in the same manner as in Example 1 except that 150 mesh plain weave sand was used as the screen plate for forming the first screen printed coating.

(The coated plate in question had uncoated areas of the first screen printing coating on four parts, and moth-eaten marks appeared, and the second screen coating could not be formed on top of it, resulting in a marked decline in design.) .

Comparative Example 2 A base color coating film and a first screen printing coating film were formed in the same manner as in Example 1. Next, direct gravure printing was performed on the first screen-printed coating using a cylinder that had been made to have the same floral pattern as in Example 1, with a maximum plate-making depth of 30 μm. In the obtained coated plate, the printing pressure changed due to the uneven thickness of the calcium silicate plate, which not only caused printing unevenness but also caused misalignment and pattern deviation. Furthermore, the printed surface was not as sharp as screen printing, the color density was low, and there was no three-dimensional appearance.

Comparative Example 3 A coated plate was produced in the same manner as in Example 2 except that 100 mesh plain weave sand was used as the screen plate for forming the second screen printed coating.

(The painted board in question cannot express thin patterns because the gauze has large grains, so the pattern is 100% missing from the petals, and the design has an ordinary appearance with two colors of pink and red.) It was a low painted board.

[Brief explanation of drawings]

FIG. 1 shows an example of the multicolored pattern coated plate of the present invention. l... Substrate, 2... First screen printed coating film, 3... Second screen printed coating film. Figure 1

Claims (3)

[Claims] (1) After applying a base color coating on the substrate as necessary, 10
A first screen printed coating film is formed by screen printing the paint using a screen plate having a mesh number of 0 mesh or less, and then the paint is screen printed onto the coating film using a screen plate having a mesh number of 150 mesh or more. A method for producing a multi-colored painted plate, comprising printing to form a second screen-printed coating film. (2) The method for producing a multicolored pattern coated plate according to claim (1), wherein the surface of the substrate is porous or has a finely uneven shape. (3) The method for producing a multicolored pattern coated plate according to claim (1), wherein the paint forming the first screen-printed coating is an ultraviolet curable paint.