JPH1119557A - Tone reproduction type coating system, coating method using the system and material to be coated - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating system for coating easily an image of good quality provided with the intermediate tone on the surface of a base of recessed and projected shape by using a roll coater. SOLUTION: In a coating system with a roll coater 8, a film document data is formed by a film document forming device 2 using a gray level original image data stored in an image data base 1. In the film document forming device 2, correction for reducing dot gains for an image data is carried out, and then the image data is binary processed by using the error diffusion dither method to form a film document data (tone reproduction image data). Based on the corrected tone reproduction image data, the excellent picture quality coating provided with the intermediate tone is applied on a base by the roll coater 8.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gradation reproduction type coating system, a coating method using the coating system, and an object to be coated. More specifically, based on a tone reproduction image created by binarizing a shading original image having a design property, a halftone coating film having a design property is applied to a base material having an uneven surface. The present invention relates to a coating system that can easily and accurately apply a coating, a coating method using the coating system, and an object to be coated.

[0002]

2. Description of the Related Art In general, wall materials having an uneven surface, exterior building materials, interior building materials, metal building materials, etc. (hereinafter referred to as "base materials") manufactured by ceramics, metal sizing (cold pressing), and the like. (Collectively referred to as "paints") is often coated with a coating material using a coating device such as a roll coater, a screen printing machine, or a spray coating machine. And among these coating equipment,
A spray coater is suitable for applying a uniform coating over the entire surface of a substrate, but is not suitable for applying a decorative coating to a part of the substrate surface. Further, the screen printing machine is suitable for applying a decorative coating to a part of the substrate surface, but is not suitable for applying a uniform coating over the entire surface of the substrate.

[0003] On the other hand, a roll coater can apply a uniform coating over the entire surface of a base material in the same manner as a spray coating machine if the circumferential surface of the transfer roll is smoothed. If a concavo-convex shape for imparting a design property is formed on the circumferential surface of the roll, a decorative coating film is applied to the base material surface in the same manner as a screen printing machine by the convex portion of the circumferential surface of the transfer roll. Therefore, it can be flexibly applied to both full-surface coating and decorative coating, and is widely used for coating a substrate having an uneven surface as described above.

When a base material is coated with a design by using such a roll coater, first, an uneven shape corresponding to the original image having the design is formed on the surface of the transfer roll. Then, a paint is applied to the surface of the transfer roll, and then the paint adhered to the protrusions on the surface of the transfer roll is transferred to the surface of the base material. Certain coatings are formed.

[0005]

In the coating using such a roll coater, the original image may be expressed in halftones by shading. However, in a conventional coating system using a roll coater, There is a problem that it is difficult to apply a halftone image corresponding to such an original image on a base material. That is, in general, when applying a halftone coating with shading to a substrate using one kind of paint, a method of expressing shading by the thickness of the coating film is used, for example. In other words, the dark portion makes the coating film thicker, and the lighter portion makes the coating film thinner to express halftones by shading. However, in the coating by the roll coater, the thickness of the paint adhered to the convex portion on the surface of the transfer roll is almost constant, and the thickness of the coating film transferred to the base material is also almost constant. For this reason, it is difficult for a roll coater to apply a halftone image to a substrate.

In the technical field of printing, conventionally, a grayscale original image expressed in halftones by grayscale is binarized by a halftone dot decomposition method or the like, and the halftone image is determined by the size of an ink deposition area on a printing surface. Although techniques such as expressing a tone are used, such techniques in the technical field of printing cannot be simply transferred to the technical field of coating. There is a demand for the development of a coating system or a coating method capable of easily and high-definition halftone coating.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and a roll coater is used to easily form a halftone image having good image quality on a surface of a substrate having an uneven shape. It is an object of the present invention to provide a coating system, a coating method, and an object to be coated that can be applied to a surface.

[0008]

A tone reproduction type coating system according to the present invention, which has been made to solve the above problems, comprises:
(A) By performing a binarization process for expressing a halftone original image having a design characteristic expressed in halftones by shading, by expressing the density of colored dots having the same dot diameter (same dimensions) with the arrangement density of colored dots, A tone reproduction device that converts the image into a binarized tone reproduction image and generates a binarized image signal corresponding to the tone reproduction image; and (b) a binarized image created by the tone reproduction device. A second original drawing creating device for creating a second original drawing based on the signal, and (c) a second original drawing creating device created by the second original drawing creating device.
A plate making apparatus for forming an irregular shape corresponding to the second original drawing on the surface of the transfer roll using the original drawing, and (d) a plurality of grooves formed on the peripheral surface in a mesh shape, and a paint supplied from a paint supply source. A mesh roll that holds a predetermined thickness on the peripheral surface by the groove portion, while the transfer roll is mounted, and the transfer roll is brought into contact with the mesh roll, and the paint held on the peripheral surface of the mesh roll And a roll coater that transfers the paint adhered to the circumferential surface onto the base material as a coating film having a design property corresponding to the grayscale original image. It is characterized by the following. In this coating system, before or after the binarization processing by the tone reproduction device, a predetermined correction characteristic (density correction function) is used to reduce the arrangement density of the colored dots (to reduce the dot gain of the colored dots). It is preferable to provide a gradation tone correction device for correcting (correcting) the image signal in the (direction). It is practical to correct the image signal by the tone correction device before the binarization process. Further, the roll coater is arranged so that (e) the outer peripheral surface thereof is pressed against the circumferential surface of the transfer roll,
After passing through the transfer position, the paint remaining on the circumferential surface of the transfer roll is collected to clean the circumferential surface, and (f) the cleaning roller contacts the circumferential surface of the transfer roll, and It is preferable that a cleaning roll for cleaning the paint adhered to the concave portion on the circumferential surface is provided.

In this coating system, the grayscale original image expressed in the halftone is converted into a grayscale reproduction image in which the halftone is expressed by the binarization process in accordance with the arrangement density of the colored dots.
That is, the image is converted into a pseudo-halftone representation image using binary recording. In this binarization process, the dot diameter of the colored dots (for example, the diameter if the dot is circular) is constant. , The highlight persistence (the image quality of the highlighted portion) when the surface is deeply carved is improved. Also, since the dot gain (dot thickening) in the halftone becomes smaller,
The gradation reproducibility and the gradation expression are improved. At the same time, the change from highlight to halftone is mild, false contour formation is prevented, and image quality is enhanced. Furthermore, in the case of multi-color coating, since the overlapping portion is small, the saturation of the coating film is increased. In general, a binarized tone reproduction image (2
Value recording) has the advantage of high stability,
There are drawbacks such as poor gradation and easy generation of moiré, but the binarization processing according to this coating system has improved such drawbacks. Also, in this binarization processing, the dot diameter of the colored dots is constant,
The dot gain when transferring paint from the transfer roll to the substrate is linear with the pressing force of the transfer roll.
This makes it easy to correct or reduce the dot gain. Therefore, the dot gain is easily corrected or reduced by the correction of the gradation tone by the gradation tone correction device. Thus, according to this coating system, it is possible to easily apply a good-quality image having a halftone on a surface of a substrate having an uneven shape by a roll coater.

It is preferable that the tone reproduction device converts an original grayscale image into a binarized tone reproduction image by an error diffusion dither method (average error minimum dither method). Here, the “dither method” is a method of binarizing each pixel of the grayscale image by assigning it to white or coloring (for example, black) with different thresholds. That is, when the binarization process is performed on all pixels with the same threshold value, a boundary line that is not present in the grayscale original image, that is, a false contour, is generated in a region where the grayscale level is close to the threshold value, and the image quality is reduced. .
Therefore, in the dither method, by changing the threshold, 2
Appropriate noise is added to the binarization process to scatter false contours and make them inconspicuous. The "error diffusion dither method" is one of such dither methods, and determines a threshold value by adding an error generated by binarization to the density value of surrounding pixels. It is.

In the above-mentioned gradation reproduction type coating system, the gradation reproduction device converts an original gray image into a binary gradation reproduction image by a density pattern method (continuous pattern dither method). Is also preferred.
Here, the “density pattern method” means that each pixel of the original image expressed in halftone is composed of, for example, n × n (n is a natural number) dot areas, and each dot area is white or white. It is intended to be able to be set to be colored (for example, black) and to express a halftone by changing the ratio of the white dot area and the colored dot area (for example, black dot area) in each pixel. is there.

In the above tone reproduction type coating system,
It is preferable that the gradation reproducing device sets the dot diameter of the colored dots to 50 μm or more. In principle,
The smaller the dot diameter, the higher the image quality or definition of the coating film formed on the substrate. However, when coating the substrate using a roll coater,
Since the base material has considerably large irregularities, the pressing force of the transfer roll against the base material must be considerably increased.If the dot diameter is too small, the shape of the convex portion of the transfer roll is distorted. The definition will be reduced. Therefore, in the case of coating with a roll coater, it is preferable to set the dot diameter to 50 μ or more.

In the above tone reproduction type coating system,
It is preferable that the transfer roll is composed of a cylindrical hard shaft and a rubber plate wound around the shaft. In this case, for example, an uneven shape corresponding to the tone reproduction image can be formed on the surface of the plate material (rubber layer) by a treatment using ultraviolet light or a laser beam. In this case, the type of design to be coated on the base material can be freely switched by merely changing the plate material without replacing the transfer roll, and the coating operation can be performed more efficiently. The transfer roll may be a cylindrical body made of rubber or sponge. In this case, a sleeve made of glass-reinforced plastic or the like may be mounted on the shaft, and the above-mentioned structure may be mounted thereon. This makes it extremely easy to attach and detach the structure.

In the above tone reproduction type coating system,
The roll coater preferably uses a paint containing titanium oxide according to the design and a white base paint having a different extender pigment ratio, and more preferably the paint contains a toning color pigment. . This is because such a paint is particularly suitable for painting a substrate having an uneven shape on the surface, and can easily and finely express a halftone.

Further, according to the present invention, a dry film thickness of 10 μm is obtained by using any one of the above-mentioned respective tone reproduction type coating systems.
A coating method characterized by coating a substrate with a coating film having a design property of m or more. According to this painting method,
An image with good image quality having a halftone can be applied to the surface of the substrate having the uneven shape by a roll coater.
Furthermore, according to the present invention, a coating film was applied on a substrate by using any of the above tone reproduction type coating systems.
An object to be coated having a design with a dry film thickness of 10 μm or more is provided.

The plate material of the transfer roll used in the present invention is:
For example, polymers of polymerizable monomers or chloroprene rubber, ethylene-chloroprene rubber, butyl rubber, silicone rubber, fluoro rubber, acrylic rubber, polysulfide rubber, natural rubber, butadiene rubber, isoprene rubber, foams of these rubbers or these It is formed of a material such as a reaction product of a rubber component and a photopolymerizable monomer.

When a polymer of a polymerizable monomer or a rubber, or a reaction product of a rubber foam or a rubber component and a polymerizable monomer is used as a material of a plate material of a transfer roll, the surface of the transfer roll can be designed and designed. Is easily formed by ultraviolet rays or a laser beam, and its durability is also improved. In particular, a composition comprising a rubber component and a photopolymerizable monomer is suitable for forming a concavo-convex shape that imparts a design property to a plate material by photopolymerization by irradiation with ultraviolet light.

[0018] The plate material having the concavo-convex shape imparting the design property is wound around a transfer roll prior to painting, for example. In addition, even when the circumference of the transfer roll is long, the plate material can be easily mounted or attached to the transfer roll. Therefore, a polymer or rubber of such a polymerizable monomer, or a reaction product of a rubber foam or a rubber component with a polymerizable monomer is very suitable for use as a material for a transfer roll plate material.

The substrate on which the coating film having a design is applied (transferred) by the roll coater according to the present invention may be any material as long as the material can transfer the paint by the roll coater. . Such base materials include, for example, those belonging to ceramics or metal sizing wall materials, building materials, etc., and inorganic plates such as gypsum plates, fiber cement plates, magnesium carbonate plates, calcium silicate plates, asbestos plates, or plywood, particles. Wooden boards such as boards and hard boards can be used. Further, a metal plate such as an aluminum plate and an iron plate, a plastic plate such as polypropylene and polyvinyl chloride, and further, a tile, a wallpaper, and the like can be given.
These substrates may have a smooth surface or an uneven surface. Further, the surface of these substrates may be subjected to an undercoat, a rust prevention treatment, an adhesion improving treatment, or the like.

The surface of the plate material (rubber layer) of the transfer roll used in the present invention has a surface hardness of JIS C 30 ° to A.
It is preferably formed of 80 ° rubber. When a transfer roll provided with a plate material having such a surface hardness is used, by pressing and arranging a cleaning roll on the transfer roll, the paint remaining on the transfer roll can be sufficiently squeezed out, and the paint can be efficiently used. It can be collected well on a cleaning roll. As described above, the remaining paint is efficiently collected, and as a result, the transfer roll receives the supply of the paint in a constant amount from the mesh roll, and transfers a coating film having a desired thickness with stable design. be able to.

The surface portion of the plate material of the transfer roll used in the present invention can be provided with a concave-convex shape having a recess depth of 0.01 to 1 mm depending on the type of design to be transferred.
By forming such a concave or convex shape having a depth or thickness, the thickness of the transferred coating film can be made more uniform as compared with the case where a conventional transfer roll is used, and a high-definition design A coating film having a property can be obtained.

It is preferable that the concavo-convex shape for imparting a design formed on the plate material of the transfer roll used in the present invention is formed so that the depth of the concave portion becomes 0.01 mm or more by ultraviolet rays or a laser beam. On the surface of the plate material of the transfer roll, a concave and convex shape for imparting design properties by ultraviolet rays or a laser beam is uniformly and accurately formed with a concave depth of 0.01 mm.
Since it can be formed as described above, it becomes possible to hold the paint only in a necessary amount on the surface of the transfer roll, and as a result, it is possible to transfer a coating film having a design to the substrate with high precision .

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below. First, an outline of a gradation reproduction type coating system according to the present invention will be described. As shown in FIG. 1, the coating system according to the present invention substantially includes an image database 1 for storing (storing) various image data, and film original data (color plate) of a gradation reproduction image using the image data. Data), an image setter comprising an image controller 4 and an automatic developing machine 5 for automatically creating a film 7 based on the film original data. It comprises a plate making device 6 to be manufactured and a roll coater 8 for applying a coating to a substrate using the plate material 21. Note that the image controller 4 is a computer, which is used here to perform various controls of the automatic developing machine 5, but also has a function of performing various image processes such as a binarization process and an image correction process. I have. Therefore, this image controller 4
It is possible to share the functions of the film manuscript making device 2 composed of a computer.

In this coating system, when applying a coating to a base material, first, image data of various original gray-scale images stored in the image database 1 and having a design characteristic expressed in halftones by gray-scale. Desired image data is selected from among them. Next, the selected image data is input to the film original creation device 2.

In the film manuscript making apparatus 2, first, data conversion processing, color separation / image division processing, finish size adjustment processing, and the like are performed on the input image data.
Next, the image data is subjected to a gradation tone correction process, and further subjected to a binarization process to create film document data (gradation reproduction image data). Note that the tone correction processing may be performed on the tone reproduction image data after the binarization processing.

As described later, the gradation tone correction processing is performed in a direction in which the arrangement density of the colored dots is reduced by a predetermined correction characteristic (density correction function or tone curve correction pattern). The correction is performed in such a way that the gain is reduced or canceled. That is, when the base material is coated with the roll coater 8, the base material has considerably large irregularities. Pressed with a very strong pressing force. For this reason, a strong pressing force acts on the convex portion of the printing plate material, particularly at a portion in contact with the bulging portion (convex portion) of the base material, and the convex portion spreads, and accordingly, the colored dot transferred to the base material. Is enlarged, that is, a dot gain occurs. Therefore, the tone is corrected in a direction in which the arrangement density of the colored dots is reduced, so that such dot gain is reduced or canceled.

As a binarization processing method, as will be described later, a binarization processing method for expressing a halftone by the arrangement density of colored dots having the same dot diameter, for example, an error diffusion dither. A method (minimum average error dither method), a density pattern method (continuous pattern dither method) and the like are used. The film original data (color plate data) of the tone reproduction image created in this way is stored (saved) on the disk 3 when it is necessary to save it.

Then, the film original data, that is, the tone reproduction image data in which the tone is corrected, is input to the automatic developing machine 5 via the image controller 4. In the automatic developing machine 5, a film 7 (a negative film or a positive film) having an image corresponding to a tone reproduction image (and an image corresponding to a grayscale original image) is created based on the film original data.

Next, a plate material 21 having an uneven shape corresponding to an image displayed on the film 7 (that is, a tone reproduction image) is produced by the plate making device 6 using the film 7. Specifically, for example, the film 7 is arranged on the surface of a rubber plate 21 and thereafter the film 7 or the plate 21
Is irradiated with ultraviolet light for a predetermined time. Here, in the transparent portion of the film 7, the ultraviolet rays pass through the film 7 and reach the plate 21, thereby curing the plate 21. On the other hand, in the opaque portion (black portion) of the film 7, since the ultraviolet rays are absorbed by the film 7, the ultraviolet light does not reach the plate 21, so that the plate 21 remains uncured. Thus, a convex portion is formed in a portion of the plate material 21 in contact with the transparent portion of the film 7, and a concave portion is formed in a portion of the plate material 7 in contact with the opaque portion. In this way, an uneven shape corresponding to the image displayed on the film 7, that is, the gradation reproduction image is formed on the plate 21.

Instead of such a plate making method, a laser engraving plate making method using a laser beam (for example, a CO ₂ laser) may be used. In this laser engraving method, when a rubber or sponge is irradiated with a laser beam,
Utilizing the property that the rubber or sponge is melted / decomposed or cut off. In the case of using such a laser engraving method, a plate 21 having an uneven shape is manufactured by the following process. That is, using a laser device capable of irradiating a laser beam to an arbitrary position of the plate 21, the laser is irradiated only to a portion of the plate 21 where a concave portion is to be formed. Here, the laser device scans the surface of the plate 21 and emits a laser beam (on) if the aiming position of the laser during the scanning is a position where a concave portion should be formed in the plate 21. Lumber 2
This part of 1 is removed by melting, decomposing or shaving the rubber or sponge. On the other hand, if the aiming position of the laser device is a position where a projection is to be formed on the plate 21, the emission of the laser beam is stopped (off), and at this time, the rubber or sponge at this portion of the plate 21 remains. Thus, plate 2
On the surface of No. 1, an uneven shape corresponding to the tone reproduction image is formed. Here, the laser device scans based on the tone reproduction image data directly input from the computer, or scans based on the read image information while reading the tone reproduction image (print, positive film, etc.). Therefore, in this case, it is not necessary to prepare the film 7 (filmless).

Further, in addition to the above plate making methods, a plate making method using the following laser beam (for example, a YAG laser beam) and ultraviolet light may be used. In the case of using this plate making method, the plate material 21 having an uneven shape is manufactured by the following procedure. In this case, it is preferable to use a photosensitive resin (photopolymer) as the plate material. In this plate making method, a laser-sensitive thin black mask is arranged on the plate 21. Then, using a laser device capable of irradiating a laser beam to an arbitrary position of the black mask on the plate 21, the black mask is irradiated with the laser only at the position corresponding to the portion where the projection of the plate 21 is to be formed. I do. Here, the laser device scans the surface of the black mask on the plate material 21 and emits a laser beam if the aiming position of the laser device during the scan is a position where a projection is to be formed on the plate material 21 ( ON), at this time, this part of the black mask is melted / removed or made transparent. On the other hand, the aiming position of the laser device is
If the position where the concave portion is to be formed in the plate material 21, the emission of the laser beam is stopped (off), and at this time, this portion of the black mask on the plate material 21 remains black. Here, the laser device scans based on the tone reproduction image data directly input from the computer, or scans based on the read image information while reading the tone reproduction image (print, positive film, etc.). Therefore, also in this case, the production of the film 7 is not required (filmless). Next, the plate 21 is irradiated with ultraviolet rays from the black mask side. In this case, the plate material 21 is hardened by ultraviolet rays in a portion where the black mask is melted, removed, or made transparent, and this portion becomes a convex portion. On the other hand, in the portion where the black mask remains, since the ultraviolet light is absorbed by the black mask, the plate 21 remains uncured, and this portion becomes a concave portion. Thus, an uneven shape corresponding to the tone reproduction image is formed on the surface of the plate 21.

Then, in the roll coater 8, the surface of the base material is coated by using the plate material 21 to form a coating film having a design property corresponding to the original light and shade image. The roll coater 8 includes a mesh roll 11 having a plurality of grooves formed on a peripheral surface thereof in a mesh shape, and holding a paint supplied from a paint supply source at a predetermined thickness on the peripheral surface by the grooves. A transfer roll 12 around which the plate material 21 is wound is provided on the surface. Then, the roll coater 8 brings the transfer roll 12 into contact with the mesh roll 11 to apply the paint held on the peripheral surface of the mesh roll 11 to the transfer roll 12.
And the paint adhered to the circumferential surface is transferred to the substrate as a coating film having a design property corresponding to the original grayscale image.

The gradation tone correction processing and the binarization processing by the film original preparation device 2 and the coating processing by the roll coater 8 in this coating system will be described in further detail. It should be noted that the gradation tone correction processing and the binarization processing may be performed by the image controller 4 instead of the film original creation device.

First, a description will be given of the gradation tone correction processing by the film original preparation device 2. As described above, in this coating system, first, tone reproduction image data (film original data) is created from the grayscale original image by binarization processing, and then a film is created from the tone reproduction image data.
After this, a plate material is manufactured from the film, and this tone correction processing corrects or reduces (cancels) the dot gain.
In order to perform this, the image data is subjected to image data before the binarization processing. In general, in a coating system using the roll coater 8, even if the halftone of the grayscale original image is correctly reproduced on the film by the error diffusion dither method or the density pattern method, the printing on the plate material 21 and the coating of the paint are performed. A phenomenon occurs in which the size of a dot (halftone dot) formed on the base material changes depending on the coating conditions such as the characteristics and the transfer roll pressing force. Among such phenomena, dot gain is a phenomenon in which dots (halftone dots) are crushed (thickened) at the time of painting, but when the influence of such dot gain is large,
A deviation occurs between the set or designated density and the actually painted density.

That is, when the tone correction processing is not performed on the image data in the coating using the roll coater 8, for example, a tone curve as schematically shown in FIG. ), The deviation or deviation of the density (output density) of the coating film (printed matter) from the density (input density). In the example shown in FIG. 6A, especially, the dot gain of the halftone when the input density is around 50% is large.

Therefore, the film manuscript making apparatus 2 performs a correction process on the image data before the binarization process using a predetermined density correction function (tone curve correction pattern) to correct or reduce the dot gain. Therefore, it is possible to faithfully reproduce the set or specified design pattern. The density correction function in this correction processing is basically an inverse function of the tone curve. For example, for a coating system of the tone curve as shown in FIG.
As shown in (b), the characteristics are set so as to reduce or cancel the dot gain.

Hereinafter, the tone curve or the density correction function will be described more specifically. For example, in the case where the image data (original image) shown in FIG.
FIGS. 8, 9 and 10 show a tone curve and a printed image or a painted image (simulated image) by flexographic printing and this painting system (design paint system), respectively. As apparent from FIGS. 8 to 10, the dot gain is very small in the case of offset printing (FIG. 8), but the dot gain is considerably large in the case of flexographic printing, and becomes saturated at an input density of about 70%. (FIG. 9). That is, in the case of flexographic printing, when the input density is about 75% or more, all become black, and therefore, it is not possible to express a gradation where the input density is about 75% or more.

Further, as is apparent from FIG. 10, in this coating system using the roll coater 8, the dot gain becomes extremely large and the dot density is saturated at about 35%. Therefore, in this coating system, if the image data is not subjected to the density correction processing, it is impossible to express a halftone having an input density of about 35% or more. That is, as can be seen from the simulation image in FIG. 10, the painting screen in this case is mostly composed of white regions and black regions, and there are very few regions expressed in halftones.

Here, for example, a tone reproduction image that has been subjected to correction processing using a density correction function 1 (tone curve correction pattern 1) as shown in FIG. 11 is shown in the left half of FIG. . Then, a film 7 and a plate 21 are created based on the tone reproduction image shown in FIG. 11, and a coating image (simulation image) in the case where coating is performed using the plate 21 is shown in FIG. Note that in this density correction function 1,
The degree of correction in the direction of decreasing the dot gain is set relatively small, so that the output density can be set to 100%. The painting screen in this case (Fig. 12)
Although the halftone area is considerably increased as compared with the case of FIG. 10, there is still a considerable gap from the original image shown in FIG.

Further, a tone reproduction image corrected by using the density correction function 2 (tone curve correction pattern 2) as shown in FIG. 13 is shown in the left half of FIG. FIG. 14 shows a coating image (simulation image) when the film 7 and the plate 21 are prepared based on the tone reproduction image shown in FIG. 13 and the coating is performed using the plate 21. In the density correction function 2, the degree of correction in the dot gain decreasing direction is set to be considerably larger than in the density correction function 1, and setting of an output density of 75% or more is prohibited. Painting screen in this case (Fig. 14)
Is quite close to the original image shown in FIG.
It can be used without any problem in practical use.

Further, a tone reproduction image corrected by using the density correction function 3 (tone curve correction pattern 3) as shown in FIG. 15 is shown in the left half of FIG. FIG. 16 shows a coating image (simulation image) when the film 7 and the plate 21 are prepared based on the tone reproduction image shown in FIG. 15 and coating is performed using the plate 21. In the correction function 3, the degree of correction in the direction of decreasing the dot gain is set to be larger than that in the case of the density correction function 2, and setting of an output density of 50% or more is prohibited. The painting screen (FIG. 16) in this case is also shown in FIG.
The image is quite close to the original image shown in FIG.

Next, the binarization process performed by the film original creation device 2 will be described. This film manuscript making device 2
In, the grayscale original image is binarized by an error diffusion dither method (average error minimum dither method) to generate a binarized tone reproduction image (pseudo halftone expression image).

In the dithering method, for example, in a black and white binarization process (not limited to black and white binary), each pixel of a grayscale image is divided into white or black with substantially different thresholds. This is a binarization method such as binarization. As such a dither method, a random dither method, an organized dither method, an error diffusion dither method (average error minimum dither method), an average limit dither method, and the like are known. It has been found that among these dither methods, the error diffusion dither method is the most suitable for the coating of the base material using. However, other dithering methods can be used for such coatings.

The error diffusion dithering is a dither method so as to determine the threshold value by slide into adding an error caused by binarizing threshold density value of pixels around, recording the read signal X _ij error E _ij between the signal Y _ij (= X _ij
−Y _ij ) on the average. In this error diffusion dither method, the pixel of interest is binarized with a certain threshold after adding an error to its density. Therefore, although the threshold value seems to be a constant value at first glance, since an error is added to the density of the pixel, the threshold is substantially changed by the error. In this error diffusion dither method, the threshold value C _ij of the pixel (i, j) is set, for example, by the following equation 1.

[0045]

[Formula 1] C _ij = 1/2 + (1 / ΣA _kl ) A _kl · E _{i + k} , _{j + l} Expression 1 In Expression 1, A _kl is a pixel (k , l). If the threshold value C _ij calculated by the equation 1 is larger than 0.5, the recording signal Y _{ij of the} pixel (i, j) becomes 1, and the pixel becomes black (colored).

In this coating system, the reason why the error diffusion dither method is used for the binarization processing of the image is as follows. That is, when the binarization process is performed on all pixels with the same threshold value, a boundary line that is not present in the grayscale original image, that is, a false contour, is generated in a region where the grayscale level is close to the threshold value, and the image quality is reduced. . Therefore, by making the threshold values different, an appropriate noise is added to the binarization processing, and false contours are scattered to make them inconspicuous.

FIG. 2A schematically shows a gray scale expression by the error diffusion dither method. In FIG. 2A, the left-side diagram shows the original gray-scale image, and the right-side diagram shows the tone reproduction image obtained by binarizing the original gray-scale image by the error diffusion dither method. FIGS. 4A and 4B show tone reproduction images obtained by binarizing the grayscale original images shown in FIGS. 3A and 3B by an error diffusion dither method. Show. Here, the grayscale original images shown in FIGS. 3A and 3B are all expressed in 256 shades of gray, and the grayscale reproduction images shown in FIGS. Are expressed in two gradations of monochrome of 100 dots / inch. As is clear from FIGS. 4A and 4B, a false contour is not formed in the tone reproduction image obtained by the binarization process using the error diffusion dither method, and the image quality is good halftone (pseudo halftone). Has been obtained.

Here, the binarization processing of the original density image by the film original preparation device 2 may be performed by a density pattern method instead of the error diffusion dither method. In the density pattern method, for example, in a black-and-white binarization process, each pixel of an original image expressed in halftone is, for example, n × n
(N is a natural number) dot areas (points), and each dot area can be set to white or black,
By changing the ratio of the number of white dot areas (white points) and black dot areas (black points) in each pixel, halftone is intended to be expressed. In this density pattern method, the density level is affected by the total number of black dot areas (black points) and the size and shape of the pattern. The number of gradations of each pixel depends on the size of the pixel. If the number of gradations is set to be large, the size of the pixel increases, so that the total number of displayed pixels decreases. On the other hand, if an attempt is made to increase the total number of displayed pixels, the size of one pixel decreases, and the number of gradations that can be expressed decreases. Therefore, this density pattern method can be said to be a binarization processing method suitable for obtaining an image having good halftone while sacrificing the image resolution to some extent.

FIG. 2B schematically shows a gray scale expression by the density pattern method. In FIG. 2 (b), the left-hand drawing shows a grayscale original image, and the right-hand drawing shows a magnified tone reproduction image obtained by binarizing a part of the original image by a density pattern method. ing. FIGS. 5A and 5B show a tone reproduction image obtained by binarizing the grayscale original image shown in FIGS. 3A and 3B by a density pattern method. Is shown. Here, each of the tone reproduction images shown in FIGS. 5A and 5B is expressed by two monochrome gradations of 300 dots / inch. As is clear from FIGS. 5 (a) and 5 (b), even a tone reproduction image obtained by the binarization processing based on the density pattern method has a good image quality.

Hereinafter, the coating process by the roll coater 8 will be described. First, the outline of the coating process will be described. FIG. 21 is a perspective view of a coated base material B having an appearance like stacked bricks. As shown in FIG.
The base material B has a brick portion 36 in which a convex portion of a base material 35 having an uneven surface is coated with a coating exhibiting a brick-like appearance, and a concave portion has a joint-like appearance of each brick portion 36. A joint portion 37 to which painting is applied is formed. Further, on the surface of the brick portion 36, there is formed a design portion 38 (design portion, pattern portion) to which a paint having a design property for expressing a realistic appearance as a brick is applied.

The base material B shown in FIG. 21 is generally coated by a procedure shown in FIG. 22, for example.
That is, as shown in FIG. 22, in this coating,
First, a base material 35 is prepared (step S1), and a paint of a first color of a color (for example, gray) corresponding to the joint portion 37 is applied to the entire surface of the base material 35 by a spray coating machine or the like. To form the first coating film 40 (step S2). Next, the first coating film 40 is dried using a continuous drying furnace or the like (Step S3).

Subsequently, a roll coater 8 provided with a transfer roll having a smooth circumferential surface (cylindrical surface) (see FIG. 17).
The brick portion 36 is formed on the surface of the convex portion of the base material 35 by using
The second color paint (for example, brown) corresponding to the second color is applied to form a second coating film 41 (step S4). Next, similarly to the case of drying the first coating film 40, the second coating film 41 is dried using a continuous drying furnace or the like (Step S).
5). Thus, on the surface of the base material 35, the brick portion 36
And joints 37 are formed (see FIG. 21).

Further, in order to enhance the design of the base material B,
A third color paint corresponding to the design portion 38, which expresses an aggregate or a mixture having different hues, is provided with a convex portion (brick portion 36).
Is applied to a predetermined portion to form a third coating film 42 (step S6). The third coating film 42 is applied by applying a coating material on the surface of the brick portion 36 using a roll coater provided with a transfer roll having irregularities of a predetermined shape on the circumferential surface. Thereafter, the third coating film 42 is dried using a continuous drying furnace or the like (Step S7). Thus,
A substrate B as shown in FIG. 21 is obtained. In this way, continuous application of a coating film having a desired design can be performed by selectively using the coating apparatus and repeatedly applying the coating material.

Hereinafter, the specific structure and function of the roll coater 8 will be described. In this embodiment, in the base material on which the first coating film and the second coating film are applied, a coating film having a design property is applied on the second coating film. The present invention is not limited to such a form, and naturally includes other forms, for example, a form in which a coating film having a design property is applied on the first coating film.

FIG. 17 is an elevational cross-sectional view schematically showing a roll coater 8 according to the present invention for applying a decorative coating film 42 (third coating film) to a substrate B having an uneven surface. It is. In addition, the base material B shown in FIG.
And a wall material or the like, which is a ceramic-related construction material having an uneven surface, which has been painted so as to have the appearance of stacked bricks. Then, on the base material B, for example, through steps S1 to S5 of a coating process as shown in FIG. 22, a first coating film 40 for forming the joint portion 37 and a second coating film for forming the brick portion 36 are formed. The two coatings 41 have already been painted.

In the paint used here, as the vehicle varnish, vinyl acetate, vinyl acetate ethylene,
Copolymers or homopolymers composed of vinyl acetate / acrylic acid ester, vinyl acetate / vinyl flopionate, styrene / butadiene, acrylic acid-based monomer, etc., inorganic polymers such as water glass, etc., used in general paints can do. As a pigment, for the base color,
It is preferable to use titanium oxide. As extenders,
In order to improve the mechanical properties of the coating film, it is preferable to use precipitated calcium carbonate, barium sulfate, talc, clay, white carbon, or the like. By setting the ratio of the base color pigment to the extender pigment in the range of 100/0 to 0.1 / 99.9, the hiding power can be adjusted to a desired value, and the design of contrast and shade gradation can be improved. Granting is possible. Also,
Various color pigments can be used to adjust the color tone. For example, zinc white, graphite, yellow iron oxide, hawker, titanium yellow, Haizan yellow, permanent yellow, molybdenum orange, hosta palm orange, red bengala, lake red, purple red bengala, quinacridone violet, navy blue, ultramarine, copper phthalocyanine, chrome green And inorganic or organic coloring pigments such as brominated copper phthalocyanine, carbon black and iron black. The ratio of the varnish, the base color pigment, the extender pigment, and the color pigment is appropriately determined depending on the content and color tone of the resulting design. Furthermore, in order to adjust properties such as viscosity of the paint, a drying accelerator, a pigment dispersibility improver for a surfactant,
Thickening agents such as carboxymethyl cellulose, colloidal silica, castor oil, thixotropic agents, anti-sagging agents, silicone oils, leveling agents such as polyether polyacrylate copolymers, defoamers, anti-repellents, and other additives. Can be added.

As shown in FIG. 17, the substrate B is transported in the direction of arrow Y by a transport mechanism (not shown). Then, the roll coater 8, the mesh roll 11 rotating in the arrow X ₁ direction, and the transfer roller 12 which rotates in direction of arrow X _2, the cleaning roller 13 rotates in the arrow X ₃ direction, rotates in the arrow X ₄ direction A cleaning roll 14 is provided. In addition, the cleaning roll 1
Reference numeral 4 moves in the directions of the double-headed arrows Z _{1 and} Z ₂ so as to be able to abut or press against the transfer roll 12 or separate therefrom.

The mesh roll 11 is for supplying a coating material having a predetermined thickness to the transfer roll 12, and is brought into contact with the transfer roll 12 at a desired pressure. The paint is supplied to the mesh roll 11 from a paint supply source (not shown) such as a paint tank. A doctor blade 17 is arranged at a predetermined distance from the peripheral surface of the mesh roll 11. The doctor blade 17 holds the paint on the mesh roll 11 and supplies the paint onto the mesh roll 11 with a film thickness (for example, about 250 μm) corresponding to the distance between the mesh roll 11 and the doctor blade 17. Has become. In addition, below the mesh roll 11, an open-type paint container 18 (pan) that receives and stores paint falling from the mesh roll 11 is arranged.

As shown in FIG. 19, a cylindrical mesh roll 11 is coaxially mounted on a rotating shaft 15, and a plurality of mesh-shaped grooves 16 (for example,
Lattice type grooves having a depth of about 30 to 400 μm are formed. The mesh-shaped groove portion 16 ensures that the paint is held at an appropriate thickness on the peripheral surface, and also prevents the paint from being biased by the centrifugal force caused by the rotation of the mesh roll 11 and the dripping of the paint. Has a function.

The transfer roll 12 is arranged so as to be able to contact the surface of the substrate B. Then, in the transfer roll 12, as shown in FIG.
A structure in which a rubber plate 21 is wound around the outer periphery of a cylindrical shaft body 20 made of metal such as aluminum so that the transfer roller 1 can contact the transfer roll 12 with a desired pressure, or a shaft. It has a structure in which a rubber plate 21 is attached to a body 20. Note that the transfer roll 12 is coaxially attached to a shaft 19. And the plate material 21
A plurality of convex portions 22 are formed on the outer surface portion of the device, and minute concave portions 23 are formed in each convex portion 22.

As described above, the surface of the plate material 21 of the transfer roll 12 has irregularities (patterns representing aggregates, lumps of a mixture of different hues, etc.) imparting a desired design property, or ultraviolet light or moss. Using a laser beam, it is formed to a thickness or depth of, for example, 0.01 mm or more, more preferably 0.05 to 2 mm. If you use ultraviolet light or laser light,
The plate material 21 can be formed with a concavo-convex shape imparting a design property with a uniform thickness or depth and with a clear contour. As a material of the printing plate 21 suitable for processing by such ultraviolet light or laser beam, for example, butadiene /
Partially crosslinked copolymer of methacrylic acid / divinylbenzene / methyl methacrylate, styrene / isoprene / styrene copolymer, maleic acid monoester-modified isoprene polymer, N, N-diethylaminopropyl methacrylamide, lauryl methacrylate and 2- Water-developable rubber molded product made of ethylene anthraquinone (for example, trade name “Flexid D-123”, hardness after curing JIS A4
0 °, 3.1 mm: manufactured by Nippon Paint Co., Ltd., a solvent-developed rubber molded product containing styrene / isoprene / styrene copolymer as a main component (for example, trade name “Sirel TDR”, “Sirel DPS flexo plate”): Du Pont Company-made).

A silver salt film having a pattern (gradation), shape, or combination thereof capable of imparting a design property is brought into vacuum contact with these rubber molded articles, and irradiated with ultraviolet rays, or by a laser. After direct writing and photopolymerization, a non-exposed portion is developed and dried using water, perchlorethylene, or the like, whereby a rubber molded body (plate material 21) having a concavo-convex shape imparting design properties is obtained. .
In order to obtain a rubber molded body (plate material 21) having a concavo-convex shape that imparts design properties by ultraviolet light or laser, a design pattern, shape,
It is also effective to convert the combination into an electrical signal corresponding to the combination to form an uneven shape on the plate 21. In addition, a rubber molded article for acrylic liquid casting (trade name "APR": manufactured by Asahi Kasei Corporation) can also be used.

As shown in FIG. 20 (b), a transfer roll 12 'having a foam layer 24 interposed between a cylindrical metal shaft 20 and a plate 21 may be used. By providing the foam layer 24 in this way, it is possible to efficiently transfer a paint film having a design to a substrate such as a wall material that is not smooth due to the elasticity of the foam layer 24. Becomes The foam layer 24 may be made of any material as long as it has high resilience and elasticity with little residual stress.
５００500 kg / m ³ (preferably 100-300 kg
/ M ³ ), but a material having a skin surface is preferable from the viewpoint of adhesiveness. The thickness of the foam layer 24 can be set to a desired value in consideration of circumstances such as whether the base material is a smooth surface or an uneven surface, but is usually 1 to 30 mm, and is preferably 1 to 30 mm. 5 to 20 mm. Note that an adhesive layer or a tape may be provided between each of the layers constituting the transfer roll 2 ′ to prevent a shift between the layers. Also,
As shown in FIG. 20C, a transfer roll 1 in which a sponge roll 25 is externally fitted on the outer periphery of a cylindrical metal shaft body 20.
2 ". In this case, the sponge roll 25 may be used.
A convex portion 26 and a minute concave portion 27 for forming a design portion are formed on the outer peripheral portion of. Further, a sleeve made of glass reinforced plastic or the like may be mounted on the shaft body 20, and the above-described structure may be mounted on the sleeve.

Again, as shown in FIG. 17, the cleaning roll 13 is
Paint on the surface of the transfer roll 12
Cleaning of the surface of. The cleaning roll 13 is preferably provided with a doctor blade 28 for scraping the paint on the cleaning roll 13 and an open paint receiver 29 (pan), but these may be omitted.

[0065] As apparent from FIG. 17, the cleaning roll 13, as viewed in the transfer roll rotation direction (direction of arrow X _2), the trailing side of the transfer position where the rubber transfer roll 12 contacts the substrate B of (rear) It is arranged at a predetermined position. The cleaning roll 13 is pressed against the surface of the rubber transfer roll 12 in order to collect the paint adhering to the surface of the rubber transfer roll 12 that has passed the transfer position. In the cleaning roll 13, the paint transferred from the transfer roll 12 to the cleaning roll 13 is scraped off by the doctor blade 28 and stored in the paint receiver 29. Here, the paint accumulated in the paint receiver 29 is appropriately returned to a paint tank or the like (not shown). If a cleaning roll is mounted in place of the doctor blade 28 and a cleaning solvent is put in the paint receiver 29, the paint adhered to the cleaning roll 13 is washed by the cleaning solvent and Be captured.

As described above, the coating film 4 having the design property is applied to the base material B.
Since the paint remaining on the transfer roll 12 after coating 2 is collected by the cleaning roll 13, the surface of the transfer roll 12 can be kept in a state in which no excess paint remains, and the The coating material supplied to the transfer roll 12 can be maintained at an appropriate film thickness with respect to the base material B. For this reason, basically, it is possible to perform coating to some extent or quite stable.

However, with such a cleaning roll 13 alone, if the viscosity of the paint supplied to the circumferential surface (surface) of the transfer roll 12 is high, or if the paint adhered to the circumferential surface of the transfer roll 12 When is cured, the paint adhering to the transfer roll 12 may not be sufficiently removed. In such a case, if the transfer of a fine decorative pattern or the like is to be performed, the paint may be clogged in the concave portion 23 which is a dug portion of the pattern of the transfer roll 12, and the like.
The outline of the decorative pattern may be lost. In addition, when it is desired to increase the thickness of the coating or to apply the coating to a substrate having considerable irregularities, it is necessary to considerably increase the transfer pressure of the transfer roll 12, but in that case, the transfer pressure is excessively increased. In such a case, the paint may accumulate in the concave portion 23 of the transfer roll 12 and the above-mentioned problem may be remarkable.

Therefore, the roll coater 8 is in contact with the circumferential surface of the transfer roll 12 (plate material 21), and is used for cleaning the paint adhered to the concave portion 23 of the circumferential surface of the transfer roll 12. A roll 14 is provided. The cleaning roll 14, as viewed in the transfer roll rotation direction (direction of arrow X _2), a trailing side of the cleaning roll 13 (the rear side), and a predetermined position of the leading side of the mesh roll 11 (front) Are located. Note that the cleaning roll 14 may be arranged on the leading side (front side) of the cleaning roll 13.

[0069] The cleaning roll 14, a cylindrical body 30 rotates in the arrow X ₄ direction, and the brush 31 in contact or pressure contact with the circumferential surface of the mounted on the circumference of the circular cylindrical body 30 transfer roll 12 Is provided. Here, the brush 31
Is, for example, a plastic brush using nylon or the like,
Or an animal brush using pig hair or the like. Then, the brush 31 comes into contact with the circumferential surface of the transfer roll 12, and effectively removes the paint that has accumulated or adhered to the concave portion 23 of the transfer roll. Further, slightly below the cleaning roll 14, water as a solvent for the paint,
An open pan 32 (pan) containing an organic solvent or the like is provided. A part of the brush 31 is immersed in the parent solvent in the pan 32,
No. 1 can effectively remove the paint in the concave portion 23 by the action of the lipophilic solvent. It should be noted that a solvent removing device for wiping off the parent solvent adhering to the circumferential surface of the transfer roll 12 may be provided on the trailing side (rear side) of the cleaning roll 14 as viewed in the rotation direction of the transfer roll 12. .

The cleaning roll 14 can be moved in the directions of the double arrows Z _{1 and} Z ₂ . Therefore, the cleaning of the concave portion 23 on the circumferential surface of the transfer roll 12 can be performed as needed, so that unnecessary cleaning can be avoided. Further, the cleaning roll 14 is
By using a roll of a metal or plastic that can be pressed together, it is possible to increase the paint collection efficiency.

The cleaning roll 14 is basically made of any material that can remove the paint accumulated in the concave portion 23 on the circumferential surface of the transfer roll 12 by sucking or scraping. Can be used. For example, a plastic brush using nylon or the like or an animal brush using pig hair or the like attached to the roll surface can be used. In addition, foams such as CR, NBR and urethane, and sponge rolls having a water absorbing property or an oil absorbing property such as a PVA foam can also be used. The hardness is preferably JISC 10 ° to 80 °, the thickness is preferably 1 to 30 mm, and the brush is preferably used. It is also possible to combine rolls and form rolls, or to arrange a plurality of these rolls.

Further, instead of the cleaning roll 14 substantially composed of the cylindrical body 30 and the brush 31 as shown in FIG. 17, urethane foam and PVA as shown in FIG.
A cleaning roll 14 ′ having a water absorbing or oil absorbing foam roll 33 (or a sponge roll) made of a foam or the like is provided so as to absorb the paint accumulated in the concave portion 23 of the circumferential surface of the transfer roll 12. Is also good. In this case, in order to squeeze the paint held by the foam roll 33 and drop the paint onto the pan 32, it is preferable to install a metal or plastic pressure roller 34 that is pressed against the foam roller 33.

Thus, in the roll coater 8,
Since the paint adhered or deposited on the concave portion 23 of the plate material 21 of the transfer roll 12 is effectively removed (collected) by the cleaning roll 14, the paint is transferred to a portion other than the design portion on the base material B. There is no problem such as that Also,
Problems such as solidification of the paint on the circumferential surface of the transfer roll 12 to increase the hardness of the circumferential surface and clogging of the concave portion 23 of the circumferential surface do not occur. For this reason, the high-definition coating film 42 having high designability can be easily and inexpensively applied to the base material B. That is, a high-definition design can be formed on the base material B, and it is not necessary to temporarily stop the process and wash the transfer roll 12,
Production efficiency is increased.

[Brief description of the drawings]

FIG. 1 is a schematic view of a coating system according to the present invention.

FIG. 2A is a photograph of a halftone image displayed on a display, schematically showing a tone reproduction characteristic by an error diffusion dither method, and FIG. 2B is a graph showing a tone reproduction characteristic by a density pattern method. It is the photograph of the halftone image displayed on the display which shows typically.

FIGS. 3A and 3B are photographs of a halftone image displayed on a display, respectively, showing a light and shade original image used for tone reproduction. FIGS.

FIGS. 4A and 4B are FIGS. 3A and 3B, respectively.
FIG. 4B is a photograph of a halftone image reproduced on a gray scale from the original grayscale image shown in FIG.

FIGS. 5A and 5B are FIGS. 3A and 3B, respectively.
7B is a photograph of a halftone image reproduced on a gray scale from the original gray image shown in FIG.

FIG. 6A is a diagram illustrating an example of a tone curve in painting, and FIG. 6B is a diagram illustrating an example of a density correction function (tone curve correction pattern) for correcting the tone curve.

FIG. 7 is a photograph of a halftone image displayed on a display, showing a grayscale original image (original image) used for setting a density correction function and its tone curve.

FIG. 8 is a photograph of a halftone image displayed on a display, showing a print image and its tone curve in offset printing.

FIG. 9 is a photograph of a halftone image displayed on a display, showing a print image and its tone curve in flexographic printing.

FIG. 10 is a photograph of a halftone image displayed on a display, showing a coating image and a tone curve of the coating system according to the present invention when no correction processing is performed.

FIG. 11 is a photograph of a halftone image displayed on a display of a density correction function 1 and a tone reproduction image created by using the density correction function 1;

12 is a photograph of a halftone image displayed on a display, showing a coating image of the coating system according to the present invention and its tone curve when the tone reproduction image shown in FIG. 11 is used.

13 is a photograph of a halftone image displayed on a display of a density correction function 2 and a tone reproduction image created using the density correction function 2. FIG.

14 is a photograph of a halftone image displayed on a display, showing a coating image of the coating system according to the present invention and a tone curve when the tone reproduction image shown in FIG. 13 is used.

FIG. 15 is a photograph of a density correction function 3 and a halftone image displayed on a display of a tone reproduction image created using the density correction function 3;

FIG. 16 is a photograph of a halftone image displayed on a display, showing a coating image of the coating system according to the present invention and a tone curve when the tone reproduction image shown in FIG. 15 is used.

FIG. 17 is a schematic view schematically showing an elevational cross-sectional structure of a roll coater used in the coating system according to the present invention.

FIG. 18 is a schematic view schematically showing an elevational cross-sectional structure of a modified example of the roll coater shown in FIG.

FIG. 19 is an external perspective view of a mesh roll used in the roll coater shown in FIG. 17 or FIG.

20 (a) is an external perspective view in which a part of a transfer roll used in the roll coater shown in FIG. 17 or FIG. 18 is broken, and (b) and (c) each show a modified example of the transfer roll. It is the external appearance perspective view which the part shown was broken.

FIG. 21 is a perspective view of a ceramic-related construction material coated with a brick-like appearance.

FIG. 22 is a flowchart showing a coating process of a substrate for ceramics and metal sizing.

[Explanation of symbols]

B: base material, 1: image database, 2: film manuscript making device, 3: disk, 4: image controller, 5
... automatic developing machine, 6 ... plate making device, 7 ... film, 8 ... roll coater, 11 ... mesh roll, 12 ... transfer roll, 12 '... transfer roll (modification), 12 "... transfer roll (modification), 13 ... cleaning roll, 14 ... cleaning roll, 14 '... cleaning roll (modification), 15 ... rotating shaft, 16 ... groove, 17 ... doctor blade, 18 ... paint container (pan), 19 ... shaft, 20 ... shaft Body, 21 ...
Plate material, 22: convex portion, 23: concave portion, 24: foam layer, 25
... sponge roll, 26 ... convex part, 27 ... concave part, 28 ... doctor blade, 29 ... paint receiver (pan), 30 ... cylindrical body, 31 ... brush, 32 ... pan, 33 ... foam roll, 34 ... pressing roll, 35 ... base material, 36 ... brick part, 37 ... joint part, 38 ... design part, 40 ... first coating film, 4
1: 2nd coating film, 42: 3rd coating film.

Claims (13)

[Claims] An original grayscale image having a design characteristic expressed in halftones by shading is converted into a binary image by a binarization process in which halftones are expressed by the arrangement density of colored dots having the same dot diameter. A tone reproduction device that converts the image into a digitized tone reproduction image and generates a binarized image signal corresponding to the tone reproduction image, based on the binarized image signal generated by the tone reproduction device. A second original drawing creating apparatus for creating a second original drawing, and a plate making apparatus for forming a concavo-convex shape corresponding to the second original drawing on the surface of a transfer roll using the second original drawing created by the second original drawing creating apparatus. A plurality of grooves are formed in a mesh shape on the peripheral surface, and a mesh roll for holding the paint supplied from a paint supply source at a predetermined film thickness on the peripheral surface by the grooves is mounted on the transfer roll, Transfer the transfer roll to the mesh The paint retained on the peripheral surface of the mesh roll by contact with the transfer roll is adhered to the peripheral surface of the transfer roll, and the paint adhered to the peripheral surface has a design property corresponding to the original grayscale image. A gradation reproduction type coating system, comprising a roll coater for transferring a coating film to a substrate. 2. A gradation tone correction device for correcting an image signal in a direction in which the arrangement density of the colored dots decreases with a predetermined correction characteristic before or after the binarization processing by the gradation reproduction device. 2. The method according to claim 1, wherein
The tone reproduction type painting system described in. 3. The gradation reproduction type coating system according to claim 2, wherein said gradation tone correction device corrects an image signal before said binarization processing. . 4. The roll coater is disposed such that an outer peripheral surface thereof is in pressure contact with a circumferential surface of the transfer roll, and collects paint remaining on the circumferential surface of the transfer roll after passing a transfer position. A cleaning roll that cleans the circumferential surface of the transfer roll, and a cleaning roll that contacts the circumferential surface of the transfer roll and cleans the paint adhered to the concave portion of the circumferential surface of the transfer roll. 2. The method according to claim 1, wherein
The tone reproduction type coating system according to any one of Items 1 to 3. 5. The tone reproduction device according to claim 1, wherein said tone reproduction device is adapted to convert a grayscale original image into a binarized tone reproduction image by an error diffusion dither method. The gradation reproduction type coating system described in any one of the above. 6. The apparatus according to claim 1, wherein said tone reproduction device is adapted to convert a grayscale original image into a binarized tone reproduction image by a density pattern method. The tone reproduction type coating system described in any one of the above. 7. The gradation according to claim 1, wherein the gradation reproducing device sets the dot diameter of the colored dots to 50 μm or more. Reproduction type painting system. 8. The transfer roll according to claim 1, wherein the transfer roll comprises a cylindrical hard shaft and a rubber plate wound around the shaft. The gradation reproduction type coating system described in one. 9. The gradation reproduction type coating system according to claim 1, wherein the transfer roll is a cylindrical body made of sponge. 10. The roll coater according to claim 1, wherein a paint containing titanium oxide according to the design and a white base paint having a different extender pigment ratio is used. The gradation reproduction type coating system described in one. 11. The gradation reproduction type coating system according to claim 10, wherein the paint contains a toning color pigment. 12. A dry film thickness of 1 using the gradation reproduction type coating system according to any one of claims 1 to 11.
A coating method characterized by coating a base material with a coating film having a design property of 0 μm or more. 13. A substrate having a dry film thickness of 10 μm or more, wherein a coating film is applied on a substrate using the gradation reproduction type coating system according to claim 1.