JPH09277691A - Printed matter, embossed product, printing plate and embossing plate, each having grain vessel sectional pattern, and method and apparatus for forming grain vessel sectional pattern - Google Patents

Abstract

PROBLEM TO BE SOLVED: To express grain vessel sectional patterns having feel close to nature by an easier method. SOLUTION: A surface of a lumber plate of natural wood is photographed, and patterns of oval grain vessel sections P1-P3 formed by cutting vessels obliquely are extracted as binary image data. On the other hand, irregular-shaped cell patterns are formed by utilizing Voromoi diagram so that mean areas of the cells are monotonically increased toward an X-axial direction, and, by allowing the longitudinal direction L of the vessel sections P1-P3 to be brought into agreement with the X-axial direction of the irregularshaped cell patterns, the irregular-shaped cell patterns formed inside the respective vessel sections P1-P3 are mapped. In such a manner, the patterns constituted from a number of grain vessel sections in which the irregular-shaped cell patterns are mapped are expressed by the printing to wall paper, etc., or by embossing process. The cellularity or fiber of plants are expressed by irregular-shaped cells, and the distribution of depth in the interior of the vessel sections is expressed by the monotone increase of cell areas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed material having a wood grain conduit cross-section pattern, an embossed product, a printing plate, an embossing plate, and a method and an apparatus for forming a wood grain conduit cross-section pattern, and particularly as a building material such as wallpaper. The present invention relates to a novel structure of a wood grain conduit cross-section pattern suitable for an artificial wood grain sheet or embossed sheet used.

[0002]

2. Description of the Related Art Decorative sheets such as wallpaper expressing the texture of natural wood are widely used as surface decorative materials for building materials, furniture, cabinets of light electrical appliances and the like. Usually, a decorative pattern imitating natural wood is printed or embossed on such a decorative sheet. The most common wood grain pattern that appears on cuts of natural wood is the wood grain conduit cross-section pattern. This wood grain conduit cross-sectional pattern is a pattern obtained mainly by cutting a conduit that is indispensable for carrying out a physiological function as a plant, and is usually composed of a set of elongated distorted elliptical patterns. In order to artificially express the texture of natural wood, it is important to reproduce the cross-sectional pattern of the wood grain conduit existing on the surface of the natural wood board as faithfully as possible. Therefore, in order to obtain an image of the wood grain conduit cross-section pattern that is the basis of printing or embossing, the pattern of the wood grain pattern that appeared on the surface of the actual natural wood was extracted by a method such as photography and extracted. A method of making a printing plate or an embossing plate based on a pattern is adopted.

In particular, when the cross section pattern of the wood grain conduit is three-dimensionally expressed by embossing, it becomes possible to actually form a wood grain conduit groove having an uneven structure on the surface of a decorative sheet or the like in a pseudo manner. For example, based on an image optically extracted from an actual natural wood board, an embossed plate is created using photolithography, etc., and if an embossed pattern is formed on the surface of wallpaper etc. using this embossed plate, it is originally Since the natural material is used as a motif, the uneven pattern formed on the wallpaper is similar to the natural grain.

[0004]

However, the above-mentioned conventional method has a problem in that the state inside the groove of the artificially formed wood grain conduit groove becomes unnatural. For example,
When the wood grain conduit cross-sectional pattern is expressed by ordinary flat printing, the wood grain conduit cross-sectional pattern formed on the surface of the printed matter is a flat pattern, so it is possible to sufficiently express the uneven structure as the conduit groove. Instead, the expression is poorly three-dimensional. On the other hand, when the wood grain conduit cross-section pattern is expressed by embossing, the uneven structure as a conduit groove can be expressed compared to flat printing, but an embossed plate is created by a general photolithography method. In that case, there is a problem that the information on the depth of the conduit groove is not reflected. A natural wood grain conduit groove is a groove obtained by cutting a conduit, and generally has different depths in each portion within the groove. However, as described above, when the pattern of the wood pattern that appears on the surface of natural wood is extracted by a method such as photography, only the information on the shape of the cut of the conduit groove is extracted, and the information on the depth is It will be lost. For this reason, the wallpaper in which the concavo-convex pattern of wood grain is transferred using an embossed plate created by a conventional general photolithography method has no choice but to make the depth of each conduit groove almost uniform, and the natural wood grain texture. Cannot be faithfully reproduced.

As described above, as a method of embossing including the texture of the depth of the actual wood grain conduit groove, there is known a method of performing multi-step etching when an embossed plate is prepared. In this method, an embossed plate having stepwise convex portions is formed by preparing a plurality of types of masks and repeating photoetching. By using this embossing plate, it is possible to obtain an embossing product having a plurality of depth distributions, and it is possible to express a texture closer to the wood grain conduit groove of natural wood. However, as the number of etchings increases, the number of processes also increases, and the cost and time corresponding thereto are required. Further, since multi-stage etching is performed, it is necessary to align the mask used for each stage, and an etching technique with high accuracy is required.

[0006] In addition, a so-called "electroforming" is performed, in which the surface shape of a natural wood board is molded with a silicone resin or the like, and a mother die used based on the mold is electroplated, and the deposited metal layer is released from the mother die. The "method" is also known, and according to this "electroforming method",
It is also possible to faithfully reproduce the three-dimensional shape of the natural wood grain conduit groove. However, this "electroforming method"
Compared with the photolithography method, more steps and time are required, and the cost becomes higher.

Therefore, an object of the present invention is to provide a novel method capable of expressing a wood grain conduit cross-sectional pattern having a texture close to that of nature by a simpler method.

[0008]

[Means for Solving the Problems]

(1) A first aspect of the present invention is a printed matter, an embossed product, a printing plate, and an embossed product, which pseudo-expresses a cross section of a wood grain conduit obtained by cutting a natural wood having a large number of conduits at a predetermined cutting surface. In the plate, a cell pattern is formed inside each section of the conduit.

(2) The second aspect of the present invention is the above-mentioned first aspect.
In the printed matter, the embossed product, the printing plate, and the embossed plate having the wood grain conduit cross-section pattern according to the aspect of (1), the cell pattern formed inside the individual conduit cross section is defined as an irregular cell pattern in which the shape of each cell is not constant. It was done.

(3) A third aspect of the present invention is the above-mentioned first aspect.
In the printed matter, the embossed product, the printing plate, and the embossed plate having the wood grain conduit cross-section pattern according to the embodiment, the cell pattern formed inside each individual conduit cross-section has an average area that monotonically increases in the longitudinal direction of the conduit cross-section. It is configured to be composed of a large number of cells having.

(4) A fourth aspect of the present invention is to form a wood grain conduit cross-section pattern which is a pseudo representation of a wood grain conduit cross section obtained by cutting a natural wood having a large number of conduits at a predetermined cutting plane. In the method, a first image data having information on a contour line of a cross section of a wood grain conduit is prepared.
And a second step that defines a large number of generating points randomly arranged on the plane, and a Voronoi diagram with the defined generating points as the core is created, and the irregular cell pattern represented by this Voronoi diagram is created. The third step of preparing the second image data having the information of 1), and the first image data and the second image data so that the amorphous cell patterns are mapped in the respective cross sections of the conduits. And a fourth step of forming a wood grain conduit cross section pattern composed of a large number of conduit cross sections having an irregular cell pattern, and a fifth step of outputting the formed wood grain conduit cross section pattern as an image. It's something that you do.

(5) The fifth aspect of the present invention relates to the above-described fourth aspect.
In the method for forming a cross-sectional pattern of a wood grain conduit according to the above aspect, in a first step, a natural wood board obtained by cutting a natural wood having a large number of conduits at a predetermined cutting surface is used, and it appears on the surface of the natural wood board. In addition, the first image data is prepared by capturing the actual wood grain conduit cross-section pattern as image data by an optical method.

(6) A sixth aspect of the present invention relates to the above-mentioned fourth aspect.
Alternatively, in the method for forming a cross-sectional pattern of a wood-grain conduit according to the fifth aspect, in the second step, generating points are randomly arranged on the XY plane so that the generating point density monotonically decreases along the X-axis direction. , In the third step, based on the mother points arranged on the XY plane, the second image data showing the irregular cell pattern in which the average area of the individual cells monotonically increases along the X axis is obtained on the XY plane. Prepared above, and in the fourth step, within the individual conduit cross-section, the X in the longitudinal direction and the second image data
The first image data and the second image data are combined so that the irregular cell patterns are mapped in a state where they are substantially coincident with the axial direction.

(7) A seventh aspect of the present invention is based on the above-mentioned sixth aspect.
In the method for forming a cross-sectional pattern of a wood-grain conduit according to the above aspect, in the second step, the maximum density and the minimum density of the generating points are defined, and from the maximum density to the minimum density in the section of length XL along the X axis. By defining random arrangements of generating points that monotonically decrease for each of the n lengths XL, n generating points are defined, and in the third stage, based on the n generating points arrangements. , N kinds of amorphous cell patterns each having an image length XL are prepared, and in the fourth step,
Image composition is performed so that an indeterminate cell pattern having an image length XL corresponding to the length in the longitudinal direction is selectively mapped for each conduit cross section.

(8) The eighth aspect of the present invention forms a wood grain conduit cross-section pattern which is a pseudo representation of a wood grain conduit cross section obtained by cutting a natural wood having a large number of conduits at a predetermined cutting plane. In the apparatus, a parameter input means for inputting a predetermined parameter, a random number generating means for generating a random number, and a random number generated are used to randomly generate mother points on an XY plane at a predetermined density indicated by the input parameter. , A Vocaloi diagram creating means for creating a Voronoi diagram centered on the populated mother points, an image inputting means for inputting image data having information on the contour line of the cross section of the wood grain conduit, and an inputting means. An image synthesizing means for performing a synthesizing process of mapping the irregular cell pattern represented by the created Voronoi diagram in the cross section of each conduit indicated by the image data And an image output means for outputting the combined image as a cross-sectional pattern of a wood grain conduit.

(9) The ninth aspect of the present invention is the above-mentioned eighth aspect.
In the device for forming a cross-section pattern of a wood grain conduit according to the aspect of 5, the generating point arranging means has a function of randomly arranging generating points on the XY plane so that the generating point density monotonically decreases along the X-axis direction. The Voronoi diagram creating means has a function of creating a Voronoi diagram showing an amorphous cell pattern in which the average area of each cell monotonically increases along the X axis based on the generating points arranged on the XY plane. However, the image synthesizing means has a function of performing mapping within the cross-section of each conduit in a state where the longitudinal direction of the conduit and the X-axis direction of the amorphous cell pattern substantially coincide with each other.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings.

<Natural wood grain conduit cross-section pattern> An object of the present invention is to form a wood grain conduit cross-section pattern as close as possible to the texture of natural wood. Therefore, first, the properties of the wood grain conduit cross-sectional pattern of a natural tree will be briefly described.

FIG. 1 shows a timber board cut out from a very general natural wood. Although a wood grain pattern as shown in the figure can be seen on the surface of such a timber board, a close observation of this wood grain pattern shows that the wood board is composed of a large number of wood grain conduit cross sections. For example, in the wood grain pattern shown in FIG. 1, when the circular partial region W surrounded by a small circle is enlarged, as shown in FIG. 2, a pattern having a large number of elliptical wood grain conduit cross sections can be observed. As described above, the grain pattern appearing on a timber board of general natural wood is constituted by the grain conduit cross-sectional pattern. This elliptical wood grain conduit cross section is the pattern obtained as a cross section of the conduit present in natural wood.

It will be shown by the model of FIG. 3 that the contour line of the cross section of the wood grain conduit has an elongated and substantially elliptical pattern.
Here, the description will be given assuming that the conduit T existing in the natural wood has a perfect cylindrical shape. This conduit T
Is a tube used as a passageway for substances necessary for sustaining the life of the plant, and extends along the growing direction of the plant. That is, in the case of a natural tree, it extends in the direction along the trunk. When cutting a timber board from such a natural tree, it is usually cut in a direction along the trunk so that a board having a larger area can be obtained. Therefore, the longitudinal axis of the conduit T and the cut surface C generally form an acute angle, as shown in FIG. Therefore, the cut end of the conduit T appearing on the cut surface C, that is, the cross section P of the wood-grain conduit has a pattern having an elongated elliptical contour line as shown in the upper part of FIG.

By the way, each of the plurality of wood grain conduit cross sections P shown in FIG. 2 is an elongated ellipse substantially along the direction of the longitudinal direction L. This is because all the conduits T existing inside the natural tree extend toward the growth direction of the tree, and therefore the cross-sectional patterns of adjacent conduits have almost the same direction. Therefore, also for the entire timber board as shown in FIG. 1, it is possible to determine the longitudinal direction L (in this example, the direction extending to the left and right in the figure) that is substantially common to the pattern of the cross-sections of many wood grain conduits existing on the surface. it can.

Now, the cross section P of such an oval wood conduit
Is a pattern of the cross section that appears on the cut surface C, and is merely the shape of the cut portion of the actual wood grain conduit groove. The actual wood grain conduit groove formed in the surface portion of the timber board is a groove with a deep depth. Therefore, let us examine what kind of distribution the depth of this conduit groove will have. Now
Consider three cross-sections C1, C2, C3 about the conduit T in the model shown in FIG. Three ellipses C1, C2, and C3 shown in the lower part of FIG. 3 are cross-sectional views at respective cross-sectional positions. Here, the horizontal broken line C indicates the position of the cutting plane C, and the hatched portion below it indicates the internal area of the conduit groove G formed in the timber obtained below the cutting plane C. . As is clear from this model, the actual depth of the conduit groove G is shallowest on the right side of the figure and deepest on the left side of the figure. Moreover, the depth gradually increases as going from right to left, and the depth monotonically increases from right to left.

Therefore, although the cross section P of the wood grain conduit shown in the upper part of FIG. 3 is a mere planar cross-section pattern, if depth information is added to this plane pattern, the right side of the figure is shallowest, The left side of the figure is deepest. In addition, as described above, since the many adjacent conduits T extend in substantially the same direction, the distribution relationship of the depths is also the same. For example, if depth distribution information that the right end of the drawing is shallow and the left end is deep is obtained for one of the plurality of oval-shaped wood conduit cross sections P shown in FIG. 2, such depth is obtained. The distribution information of is applicable to all the other cross sections P of the wood grain conduit in common.
If the field of view is further expanded, such depth distribution information can be commonly applied to all the cross sections of many wood grain conduits formed on the timber board shown in FIG.

In the above model, the conduit T is treated as a simple cylindrical shape, but it is rare that the actual conduit has a geometrically perfect cylindrical shape, and it is natural. Therefore, it naturally has an irregular shape. Some of them are more like a conical shape that is gently inclined from the root to the canopy, rather than a cylindrical shape (cylindrical shape). FIG. 4 shows an example of a cross-sectional pattern of wood grain conduits that appears on an actual natural wood lumber board. In this way, the cross section P of the wood grain conduit that appears in the actual natural timber board
Is not a perfect elliptical shape as shown in FIG.
Both are irregularly shaped. In addition, a portion where a plurality of conduits have adhered is also observed. However, the longitudinal direction L (vertical direction in the figure in the example of FIG. 4) is common to all wood grain conduit cross sections, and it is possible to determine the common longitudinal direction L by observing the entire timber board. Is.

As described above, the cross section of individual wood grain conduits appearing in an actual natural wood lumber board is not a geometrically accurate ellipse but rather a rather irregular irregular shape. However, in the following description, explanation will be given. For the sake of convenience, we will treat each wood grain conduit cross section as a simple elliptical pattern.

<Conventional product having wood grain conduit cross-section pattern> The wood grain conduit cross-section pattern as shown in FIG. 4 is used for decoration of products in various fields including construction materials such as wallpaper. When this pattern is used as a printed matter, the inside of the cross section of the conduit (the portion shown in black in FIG. 4) is usually expressed by coloring it with a relatively dark color ink. When this pattern is used as an embossed product, the region corresponding to the inside of the conduit cross section is processed into a concave shape for expression. Depending on the application, the expression by printing and the expression by embossing may be used in combination. For example, in a relatively high-quality wallpaper product, a wood grain pattern printed matter is created by printing a wood grain conduit cross-sectional pattern as shown in FIG. 4, and the same pattern is embossed on the wood grain patterned printed material to form an uneven structure. The method of expression is also used.

As a method for producing an embossing plate used for embossing the wood grain conduit cross-section pattern, the wood grain pattern appearing on the surface of natural wood is extracted by a method such as photography, and the extracted pattern is extracted. A method of forming a concavo-convex structure on the embossing plate by using a photolithography method is generally used. However, in the ordinary photolithography method, since the concavo-convex pattern is formed on the embossing plate only by the information on the contour shape of the cross section of the wood grain conduit, the information on the depth of the conduit groove cannot be reproduced. FIG. 5 is a cross-sectional view showing an example in which the embossed plate 10 is provided with a concavo-convex structure by using the information on the contour line of the planar cross section P of the wood grain conduit. The convex portion 11 formed on the embossing plate 10 has an elliptical shape in a plan view, but its height is substantially uniform (actually, the corners are slightly rounded based on the characteristics of the etching process. It has a monotonous raised structure.

When such a conventional embossing plate 10 is used to perform embossing for transferring the uneven structure to the wood grain print 20 (for example, a vinyl chloride sheet) (for example, the embossing plate 10 is heated while applying heat). As shown in FIG. 6, a concave portion having an elliptical shape in plan view is formed, but the depth is almost uniform (actually, as described above). In addition, the corners are slightly rounded), forming a monotonous groove structure. Usually, the ink is applied to the inner surface of the recess, but when observing the surface of such a wood grain pattern printed material 20, there is no depth distribution in the formed recess, and therefore, the actual natural wood. Compared with the case of observing the conduit groove of No. 2, the texture will be slightly different, and a feeling of strangeness slightly different from that of natural wood will remain.

Therefore, in order to express the conduit groove having the depth distribution, a method of forming the embossing plate 10 by a multi-step etching method or an electroforming method has been proposed. As mentioned above, there is a problem that the cost becomes high.

<Wood grain conduit cross-section pattern according to the present invention> When expressing the above-mentioned wood grain conduit cross-section pattern, forming a cell pattern inside each of the conduit cross-sections gives a more natural texture. I found the fact that I can do it. Here, the cell pattern is a pattern composed of a large number of cells each surrounded by an outer shell, and in particular, in order to express a natural texture,
It is preferable to use an amorphous cell pattern in which the shape of each cell is not constant.

FIG. 7 is a diagram showing an example of such an irregular cell pattern. Here, the small closed region surrounded by a line (outer shell) is each cell, and each cell is not constant in shape or size. FIG. 8 is a diagram showing a state in which such an amorphous cell pattern is mapped in the cross section of one wood grain conduit. If the wood grain conduit cross-section pattern according to the present invention is used for a flat printed matter, the inside of each pipe cross-section of the conventional wood grain conduit cross-section pattern as shown in FIG. 4 (portion blackened in FIG. 4) is used. An irregular cell pattern as shown in FIG. 7 (actually, a cell pattern obtained by considerably reducing the pattern shown in FIG. 7) may be mapped. In addition, if the wood grain conduit cross-section pattern according to the present invention is used for an embossed product, the process shown in FIG.
As shown in FIG. 9, a pattern consisting of a cross section of a wood grain conduit in which an amorphous cell pattern is mapped is prepared as a photomask, and etching is performed using this photomask to create an embossed plate 15 whose cross section is shown in FIG. Then
The embossing plate 15 may be used to emboss a wood grain print 25 as shown in FIG. 10, for example.

More specifically, referring to FIG.
Prepare a photomask in which all portions outside the contour line of the elliptical wood conduit cross section P are painted black, form a negative resist layer on a metal plate, and place the prepared photomask on this resist layer. Then, the unexposed portion (black portion of the photomask) is removed by development, and the exposed portion of the metal plate is etched to obtain the embossed plate 15 having the structure shown in FIG. This embossed version 1
In 5, the slit 12 is formed in the portion corresponding to the outer shell of the irregular cell pattern. This embossed version 15
When embossing is performed using, as shown in FIG.
In the recess 21 formed on the surface of the wood grain print 25,
A honeycomb structure in which the partition walls 22 are formed at positions corresponding to the outer shell of the irregular cell pattern is formed. However, in the actual etching process, the smaller the portion, the lower the filling efficiency of the etching solution and the slower the etching rate. Therefore, in the embossing plate 15 shown in FIG.
The slit 12 becomes shallower than the height of the slit. Therefore,
The height of the partition wall 22 formed on the actual wood pattern print 25 is smaller than the depth of the recess 21, and an uneven pattern having fine partition walls is formed at the bottom of the recess 21. .

The shades and irregularities of the irregular cell pattern to be mapped inside the cross section of each conduit may have a relationship opposite to that of the above embodiment. For example, when the present invention is applied to a flat printed matter, as shown in FIG. 8, the outer shell of the cell may be shown with ink darker than the inside of the cell. The ink may be darker than the outer shell (the black-and-white inversion of the irregular cell pattern in FIG. 7 is mapped to the inside of each conduit cross section). Alternatively, when the present invention is applied to an embossed product, as shown in FIG. 10, a portion corresponding to the outer shell of the cell in the recess 21 may have a convex structure as the partition wall 22. The structure may be such that the portion corresponding to the inside is convex and the portion corresponding to the outer shell of the cell forms a slit.

The cell pattern to be mapped inside the individual conduit cross section must be a fine cell pattern in which the area of each individual cell is sufficiently smaller than the area of the conduit cross section. In the case of a general wood grain conduit cross-section pattern, the actual size of each conduit cross section is about 1 mm to 50 mm in length (dimension in the longitudinal direction) and about 0.1 mm to 1 mm in width. Therefore, it is preferable to use a pattern of cells having a diameter of about 0.01 mm to 1 mm as a cell pattern to be mapped inside the cross section of the conduit.

As described above, when the cell patterns are mapped inside the individual conduit cross sections, the entire wood grain conduit cross section pattern is observed with a more natural texture. For example, even if the printed matter is the same plane, the irregular cell pattern as shown in FIG. 8 is provided inside each conduit cross section rather than the printed matter in which the inside of each conduit cross section is painted black as shown in FIG. The printed matter on which is mapped has a texture closer to that of natural wood. Although theoretical analysis of the reason why such a phenomenon occurs has not been conducted at this stage, it is possible to map a fine cell pattern to the so-called rough texture such as plant cytoplasm or fibrous material on the cross section of each conduit. The inventor of the present application believes that a texture closer to that of natural wood can be felt when the naked eye is observed.

<Expression of Depth Distribution> In the above embodiment,
An amorphous cell pattern as shown in FIG. 7 was mapped inside each section of the conduit. The irregular cell pattern shown in FIG. 7 is a pattern in which a large number of cells having irregular sizes and shapes are randomly arranged, and the cell size has no regularity. Here, an amorphous cell pattern as shown in FIG. 11 is considered in place of the amorphous cell pattern shown in FIG. The pattern shown in FIG. 11 is an irregular cell pattern in which the average area of each cell monotonically increases from left to right. Now, defining the X axis in the horizontal direction of the drawing and the Y axis in the vertical direction of the drawing, the irregular cell pattern shown in FIG. 11 is as shown in the graph of FIG.
The cell pattern is such that the average area S of the cells is controlled by the position x on the X axis, and the average area S of the cells monotonically increases as the coordinate value x on the X axis increases. Can be said. Of course, each cell is an irregular cell whose shape and size are non-uniform, but the average area S of the cell has regularity with respect to the position x on the X axis. As can be seen intuitively from FIG. 11, in this pattern, the cells arranged closer to the left side of the figure are smaller, and the cells arranged toward the right side of the figure are larger.

In carrying out the present invention, the inventor of the present application has found that the average area of cells as shown in FIG. 11 increases monotonically in a predetermined direction rather than using a uniform irregular cell pattern as shown in FIG. It has been found that using a fixed cell pattern is more effective. That is, by using the amorphous cell pattern shown in FIG. 11, it becomes possible to represent the depth distribution inside the cross section of each conduit.
However, it is necessary to impose one condition when mapping. The condition is that mapping is performed so that the X-axis direction of this cell pattern (direction in which the average area of cells monotonically increases) and the longitudinal direction of each conduit cross section substantially coincide with each other.

FIG. 13 shows an example of mapping the amorphous cell pattern shown in FIG. 11 inside the cross section of the conduit under such conditions. In FIG. 13, three wood grain conduit cross sections P are shown.
1, P2 and P3 are shown, the longitudinal direction L of each of them is aligned with the X-axis direction, and the mapped amorphous cell pattern has cell sizes along the longitudinal direction L of each conduit cross section. Is changing.

Comparing the cross section P of the wood grain conduit shown in FIG. 8 with the cross sections P1, P2 and P3 of the wood grain conduit shown in FIG. 13, the former feels that the depth distribution inside the conduit groove is constant. In the latter case, the depth distribution inside the conduit groove is X.
It feels like it is changing along the axial direction. Specifically, when observing the cross-sections P1, P2, P3 of the wood grain conduit shown in FIG. 13, the left side (smaller cell) of the figure becomes deeper than the right side (larger cell). It gives the illusion of being present. As described above, it is thought that the density distribution as grooves is probably related to the concentration distribution inside the cross section of each conduit due to the illusion, even though the printing is performed on a flat surface. In the example shown in FIG. 13, the higher density left part gives a deeper impression. As a matter of fact, reversing the black and white of this irregular cell pattern, this time, the right side (larger cell) is deeper than the left side (smaller cell) The illusion of Further, in the case of an embossed plate having a concavo-convex structure, it seems that smaller cells generally give a deeper impression.

In this way, when an irregular cell pattern in which the cell size changes along the longitudinal direction L of each conduit cross section is mapped, which of the larger cell and the smaller cell looks deeper. Since the problem of "," is a problem in which the density of the ink used for printing and the relationship of the unevenness when performing embossing are complicatedly entangled, it cannot be unconditionally determined. In any case, however, the illusion that the depth distribution monotonically changes from one to the other is obtained for each individual conduit cross section. Moreover, as described above, in the wood grain conduit cross-section pattern composed of a large number of conduit cross-sections, the longitudinal direction L of each conduit cross-section is almost common, so that even in the direction in which the depth distribution monotonously changes, Almost the same for the cross section of the conduit.

Such a monotonous depth distribution plays an important role in making the texture feel more like natural wood.
The reason can be easily understood by referring to the conduit cross-section model shown in FIG. As described above, the conduit groove G formed by cutting the substantially cylindrical conduit T with the predetermined cutting surface C has a monotonous depth gradient in the longitudinal direction L of the conduit cross section. Therefore, even if no depth gradient actually exists, if a monotonous depth gradient in the longitudinal direction L can be pseudo-presented, a texture closer to that of natural wood can be expressed. Therefore, as shown in FIG.
Each of the wood grain conduit sections P1, P2, P3 in which the irregular cell pattern in which the cell size changes along the
Even if it is only a flat printed matter, when it is observed with the naked eye, an illusion of a conduit groove having a monotonous depth gradient occurs, and a texture close to that of natural wood is felt. In the case of embossed products, even when the depth of the groove is uniform, when observed with the naked eye,
After all, the illusion of a conduit groove with a monotonous depth gradient occurs, and the texture close to that of natural wood is felt.

In a wood grain conduit cross-section pattern obtained from an actual natural tree, as shown in FIG. 4, the lengths of individual wood grain conduit cross-sections P are not uniform and vary from short to long. As described above, it is not preferable to map the same pattern as shown in FIG. 11 to a large number of wood-pipe conduit cross sections P having different lengths. Because Figure 11
If the same pattern shown in (1) is mapped to a very short grain cross section P of the wood grain, only a part of it can be mapped, so that a sufficient depth gradient cannot be expressed. Conversely, mapping to a very long wood grain cross section P will result in regions that are not partly mappable (for example, mapping the pattern shown in FIG. 11 inside a duct cross section with a length of XL or greater results in Mapping cannot be done for the part exceeding XL). Therefore, actually, n kinds of irregular cell patterns having different image lengths shown by length XL in FIG. 11 are prepared, and an image length corresponding to the length in the longitudinal direction is prepared for each conduit cross section. It is preferable to perform mapping by selecting an amorphous cell pattern having XL. For example, in the example shown in FIG. 13, each wood grain conduit cross section P1, P2
P3 has lengths L1, L2, L3 in the longitudinal direction.
The most suitable irregular cell pattern may be selected and mapped according to the above.

[0043]

EXAMPLES The present invention will now be described in more detail with reference to specific examples.

§1. Utilization of Voronoi Diagram In the present invention, an amorphous cell pattern is mapped inside the cross section of an individual wood grain conduit. Here, a brief description of a Voronoi diagram suitable for use as this amorphous cell pattern will be given. deep.

Now, as shown in FIG. 14, six mother points M1 to M6 are defined on the plane. Then, the matter as to which of the mother points the arbitrary point Q on this plane belongs to is defined mathematically. Usually, the most commonly used definition is "belong to the sphere of influence of the mother point with the smallest Euclidean distance (so-called geometric distance between two points)." In the example shown in FIG. 14, the mother point having the closest Euclidean distance to the point Q is the mother point M2, so the point Q belongs to the sphere of influence of the mother point M2.
In this way, if all the points on the plane belong to any of the generating points M1 to M6, a polygon showing the influence zone of each generating point is obtained as shown in FIG. In FIG. 15, the hatched polygon corresponds to the sphere of influence of the mother point M2. That is, the generating point M2 is a generating point having the smallest Euclidean distance with respect to all the points in the hatched area. The polygons thus obtained are called Voronoi polygons, and this set of Voronoi polygons is a Voronoi diagram (Voronoi diagram).
diagram). In short, the Voronoi diagram is a state in which a plane is divided by a set of polygons showing the influence zones of each mother point when n mother points M1, M2, ..., Mi, ... Mn are defined on the plane. It can be said that it is a diagram.

When generating the Voronoi diagram, if the generating points are regularly arranged in advance, the plane division pattern indicated by the generated Voronoi diagram will also be regular. For example, as shown in FIG. 16, the same equilateral triangle is used to fill the plane, and individual generating points Mi are defined at the vertex positions of each equilateral triangle. When a Voronoi diagram is created based on a large number of generating points Mi arranged regularly in this way, a large number of regular hexagons Hi as shown in FIG. 17 are obtained as Voronoi polygons.
The plane is regularly divided by this regular hexagon group.

In the present invention, it is possible to use such a completely regular cell pattern, but in expressing the cytoplasm and fiber of a plant, an irregular cell pattern as shown in FIG. 7 is used. Is preferred. In order to form such an irregular cell pattern, a random mother point arrangement may be used as the original mother point arrangement instead of the regular arrangement. The irregular cell pattern shown in FIG. 7 defines a regular mother point arrangement as shown in FIG. 16 on the XY plane and then displaces it in the X-axis direction with respect to each mother point Mi (xi, yi). The amount Δx and the displacement amount Δy in the Y-axis direction are generated as random numbers for each generating point, and the new position of each generating point is set to Mi (xi) based on the displacement amounts Δx and Δy.
This is a pattern formed by performing a displacement (movement) of + Δx, yi + Δy) and obtaining a Voronoi diagram based on the mother points after the displacement. Note that, as shown in FIG. 11, a specific example for forming an amorphous cell pattern in which the average area S of cells monotonically increases along the X-axis direction will be described later.

By the way, as a condition for creating a Voronoi diagram based on a large number of generating points having a specific arrangement, the condition "Euclidean distance is the minimum" is used in the above-described embodiment. Usually, when we say "Voronoi diagram", it is common to refer to those created using the condition "Euclidean distance is minimum", but as a condition for creating a Voronoi diagram, Other various conditions can be set. For example, XY shown in FIG.
In the coordinate system, the “Euclidean distance” between the generating point M and an arbitrary point Q is represented by (dx ² + dy ² ) ^1/2 , but instead of this “Euclidean distance”, for example,
A special distance represented by (k1 · dx ² + k2 · dy ² ) ^1/2 may be defined, and the condition “this special distance is the minimum” may be set. In this case, different Voronoi diagrams can be obtained by changing the values of the parameters k1 and k2.

Alternatively, "four adjacent distances" or "eight adjacent distances" may be defined, and the condition "this adjacent distance is minimum" may be set. Here, "four adjacent distances" or "eight adjacent distances" refer to the following distances. Now, defining a pixel array as shown in FIG. 19 (a), the four pixels shown by hatching the pixel Q in the center in the vertical and horizontal directions are called "four adjacent pixels". To do. Similarly, a pixel array as shown in FIG. 19B is defined, and eight pixels indicated by hatching adjacent to the center pixel Q vertically, horizontally, and diagonally are referred to as “eight adjacent pixels”. I will call it. Here, considering a pixel array as shown in FIG. 20, a pixel M (corresponding to the mother point M in FIG. 18)
The “four adjacent distance” between the pixel and the pixel Q (corresponding to the point Q in FIG. 18) is “must move to any one of the four adjacent pixels,
Is defined as "the minimum number of movements required to reach from the pixel Q to the pixel M according to the moving condition". Similarly, the "eight adjacent distance" between the pixel M and the pixel Q is "always any of eight adjacent pixels". The minimum number of movements required to reach from the pixel Q to the pixel M according to the movement condition of moving to one. In the example shown in FIG. 20, the “four adjacent distance” between the pixel Q and the pixel M is 8, and the “eight adjacent distance” is 5.

Besides this, it is possible to create a Voronoi diagram under various conditions. In short, what is the “Voronoi diagram” for forming the cell pattern used in the present invention, as long as it is a power distribution map obtained by mathematically defining the spatial power range of the generating point in some way? It does not matter even if it is obtained by such a definition. Mathematically, various Voronoi diagrams such as “cutting Voronoi diagram”, “farthest point Voronoi diagram”, and “Circle Voronoi diagram” are known.

§2. A wood grain conduit according to an embodiment of the present invention
Method of Forming Cross Section Pattern Next, a method of forming a wood grain conduit cross section pattern will be described based on a specific example using the Voronoi diagram described above. FIG. 21 is a flowchart showing the procedure of the method according to this embodiment. First, in step S1, first image data having information on the contour line of the cross section of the wood grain conduit is prepared. For example, as is generally done conventionally, the surface of a lumber board cut out from natural wood having a large number of conduits is photographed, and the cross-sectional pattern of the wood grain conduit on this photograph is captured as raster image data by a scanner, By binarizing each pixel so as to have either a black or white pixel value, a wood grain conduit cross-sectional pattern as shown in FIG. 4 can be prepared as image data. As described above, the method of capturing the actual wood grain conduit cross-section pattern appearing on the surface of the natural wood board as image data by the optical method is the most efficient method at present. However, the image data to be prepared in step S1 is
Any form of data can be used as long as it has information about the contour of each conduit section. Therefore, a method of generating a wood grain conduit cross-sectional pattern as shown in FIG. 4 may be adopted by using a technique of so-called computer graphics without using natural wood.

Subsequently, in step S2, generating points are randomly arranged. Specifically, the XY plane may be defined, and a large number of generating points randomly arranged on the XY plane may be defined. Then, in step S3, a Voronoi diagram for these generating points is created, and second image data having information on the amorphous cell pattern represented by this Voronoi diagram is prepared. As described above, at the stage of generating the generating points, if the generating points are randomly arranged so that the generating point density on the XY plane becomes uniform, then an irregular cell pattern as shown in FIG. 7 can be generated. By randomly arranging the generating points so that the generating point density monotonously changes along the axial direction, an irregular cell pattern composed of cells whose average area changes monotonously as shown in FIG. 11 can be generated. In step S3,
The irregular cell pattern thus generated may be prepared as raster image data including a set of pixels having a pixel value of either black or white.

Then, in step S4, image processing is performed to map the amorphous cell pattern in each section of the conduit. That is, the first image data prepared in step S1 and the second image data prepared in step S3 are combined. as a result,
For example, a wood grain conduit cross-sectional pattern as shown in FIG. 13 will be obtained. Here, the important point is that the longitudinal direction L of the cross section of each conduit and the X-axis direction of the irregular cell pattern are made to substantially coincide with each other. However, as already mentioned, for general wood grain conduit cross-section patterns,
Since the common longitudinal direction L can be defined, when performing mapping, the common longitudinal direction L and the X axis of the amorphous cell pattern may be matched.

Finally, in step S5, the formed wood grain conduit cross-section pattern is output as an image. Specifically, a wood grain conduit cross-sectional pattern as shown in FIG.
It will be output on the original film or mask plate. Finally, the printed film original plate is used to print the wood grain conduit cross-section pattern for mass production of printed matter, or the embossed plate is created by etching using the output mask plate, and this embossed plate is used. Due to the embossing, the embossed products will be mass-produced.

Then, in step S2 described above, X
An example of a specific method of randomly arranging the mother points so that the mother point density monotonously changes along the axial direction will be described based on the flowchart of FIG. Here, as shown in FIG.
An image area having an image length XL and an image width YL is set on the XY plane, and within this image area, as the X coordinate value x increases from x = 0 to x = XL, the average area S of the cells is calculated. Consider the arrangement of generating points for creating an irregular cell pattern that monotonically increases as shown in FIG. In order to perform such mother point arrangement, first, in step S11 of the flowchart shown in FIG. 22, parameters are input. here,
The image length XL and the image width YL are the dimensions of the image area where the irregular cell pattern is to be formed, as described above. Also, the minimum cell diameter dmin and the maximum cell diameter dmax
Is the expected diameter of the smallest and largest cells formed.

FIG. 23 is a graph showing the distribution of the expected area E of the formed cells. The expected area E of the cell monotonically increases as the position (X coordinate value) on the X axis increases from 0 to XL, as shown in the graph indicated by the solid line in the figure. In this embodiment, the expected area E of the cell is expressed in a linear form of E = dmin ² + (x / XL) · (dmax ² −dmin ² ), and the graph showing the relationship between E and x is a straight line. become. By substituting x = 0 into this equation, the second term on the right side becomes 0, and E = dmin ² is obtained. This is because the expected area E of the cell at x = 0 is dmin ² and the minimum diameter dmin at the left end of the set image area.
Cells are expected. Also, by substituting x = XL into this equation, the second term on the right side becomes (dmax ² −
dmin ² ) and E = dmax ² is obtained. this is,
The expected area E of the cell at x = XL is dmax ² ,
At the right end of the set image area, a cell having the maximum diameter dmax is expected. A cell having an intermediate diameter between the minimum diameter dmin and the maximum diameter dmax is expected in the intermediate region from x = 0 to XL, and the expected cell diameter is such that x increases. It grows larger as you do. Of course, the above equation is shown as an example, and the relation between E and x does not necessarily have to be a linear relation, and can be expressed by using a quadratic equation or a cubic equation, or by using an exponential function or a logarithmic function. It does not matter if it is represented. In short, the expected cell area E
Need only be changed monotonically in the X-axis direction.

As described above, in order to generate an irregular cell pattern in which the expected area E of the cell monotonically increases with the increase of x using the Voronoi diagram,
When arranging the generating points that are the basis of the Voronoi diagram, the generating points may be arranged so that the generating point density monotonically decreases as x increases. This can be intuitively understood by looking at the irregular cell pattern shown in FIG. That is, in this cell pattern, the population density increases toward the left side, and the population density decreases toward the right side. Therefore, FIG.
As shown by the dashed-dotted line graph in FIG. 3, the population density D may be set to be smaller as the x increases, contrary to the expected area E of the cell.

The flow chart shown in FIG. 22 shows one procedure for performing mother point arrangement based on such an idea. First, as described above, in step S11, the image length XL, the image width YL, the minimum cell diameter dmin, and the maximum cell diameter dma.
Set x. Then, in step S12, the image area is set. That is, the image length X on the XY plane
An area of L and image width YL is secured. Specifically, FIG.
As shown in, the coordinate value x = 0 to (XL−
1) XL pixels, the coordinate value y in the Y-axis direction
= 0 to (YL-1) YL pixels are arranged, and a pixel array including a total of (XL × YL) pixels is defined. Each of the following processes is the sum (XL × Y
It is nothing but the processing for deciding whether or not to arrange the generating points for each of L) pixels. In FIG. 24, pixels filled with black represent pixels determined as pixels on which the mother points are arranged (hereinafter, referred to as mother point pixels). Since the generating points used when creating the Voronoi diagram are geometric points that do not have an area, for example, when calculating the Voronoi diagram, for example, the center of each of the generating black pixel points It can be handled as if each mother point is defined at the point position.

In the next step S13, the X coordinate value x is set to the initial value 0, and in the subsequent step S14, E = f
Substituting the X coordinate value x into the function (x), the expected area E of the cell is calculated. In this embodiment, as the function f (x), as described above, f (x) = dmin ² + (x / XL) · (dmax ² −dmi
n ² ) is used, and E = dmin ² is obtained as a result of substituting the initial value x = 0. In a succeeding step S15, the Y coordinate value y is set to the initial value 0. Then, in step S16, it is determined whether or not the expression RND <1 / E holds. Here, E is the expected area of the cell obtained in step S14, and RND is a random number value that takes an arbitrary value between 0 and 1. If this formula is established, the process of placing the generatrix is executed in step S17, and if not established, the process of not placing the generatrix is executed in step S18. In other words, it is decided whether or not the pixel indicated by the coordinate value (x, y) becomes the mother pixel, and with the probability (1 / E),
This pixel will be the mother pixel.

When the process for determining whether or not the pixel indicated by the coordinate value (x, y) is the mother pixel is completed in this way, the Y coordinate value y is incremented by 1 in step S19. Then, in step S20, the process from step S16 is repeatedly executed as long as y <YL is determined.
In this iterative process, in FIG. 24, with the X coordinate value x fixed, the Y coordinate value y is increased by 1 and each pixel indicated by the coordinate value (x, y) becomes a mother pixel. It can be said that it is a process of sequentially determining whether or not.

In step S20, the Y coordinate value y is Y.
When it is determined that L has been reached, the X coordinate value x is incremented by 1 this time in step S21. Then, in step S22, the process from step S14 is repeatedly executed as long as it is determined that x <XL. This iterative process is a process of sequentially determining whether or not the pixel of each column becomes a mother pixel while increasing the X coordinate value x by 1 in FIG. However, each time the X coordinate value x is updated, step S
Since the expected area E of the new cell is calculated in 14, the probability of becoming the mother pixel is changed in step S16.

The relationship between this change in probability and the population density is
It can be easily understood by considering the following concrete numerical values. For example, in step S11, the minimum cell diameter d
Let's assume that min = 10 and maximum cell diameter dmax = 100. Then, by substituting x = 0 into the formula E = dmin ² + (x / XL) · (dmax ² −dmin ² ), E = 100, and x =
Substituting XL results in E = 10000. Here, focusing on the determination in step S16, RND is 0 to 1
Since it is a random number that takes a value between 1 and 2, when x = 0, 1 /
It can be seen that the probability of becoming a mother pixel is 100 with the probability of 100, whereas that of x = XL is that there is a probability of 1/10000 with the mother pixel. If it is determined with such a probability whether or not the mother pixel is used, finally, the mother density at the left end of the image area represented by x = 0 (ratio of mother pixels to all pixels) is 1/100
Therefore, the density of the generating points at the right end becomes 1/10000, and a density distribution corresponding to the generating point density D shown by the alternate long and short dash line in FIG. 23 is obtained.

In this way, if it is determined in step S22 that the X coordinate value x has reached XL, the procedure for the mother point arrangement is complete. If a Voronoi diagram is created based on the mother points thus arranged, as shown in FIG. 11, it is possible to obtain an irregular cell pattern composed of cells whose average area monotonically increases. The expected area E and the generating point density D of the cell shown in FIG. 23 are merely expected values, and the cell area and generating point density of an actually formed amorphous cell pattern as shown in FIG. It does not exactly match the initially set expected value. Therefore, step S11
There may be a cell having a diameter smaller than the minimum cell diameter dmin set as a parameter in
On the contrary, there may be a cell having a diameter larger than the maximum cell diameter dmax. However, there is no change in that the average area S of each cell monotonically increases along the X axis, and there is no problem in practical use.

As described with reference to FIG. 13, the cross sections P1, P2, P of the wood grain conduits having different lengths, respectively.
It is preferable to map an irregular cell pattern having an image length XL corresponding to the lengths L1, L2, and L3 to the cell No. 3, respectively. Therefore, in practice, the procedure shown in FIG.
This is repeated a number of times to create n kinds of amorphous cell patterns having different image lengths XL. Then, when mapping the irregular cell pattern in the cross section of each wood grain conduit, the pattern having the most suitable image length XL is selected from the n types of irregular cell patterns (for example, the cross section of the wood grain conduit). Image length XL in an irregular cell pattern having an image length XL larger than the length in the longitudinal direction of
Of the minimum) is selected, and the selected pattern may be mapped.

Further, depending on the wood grain conduit section pattern used, there may be a conduit section having a width wider than the image width YL of the prepared irregular cell pattern. Therefore, in order to cope with such a case, it is preferable to prepare an amorphous cell pattern that is repeatable in the width direction. Specifically, when two identical patterns shown in FIG. 11 are prepared and these two patterns are arranged side by side vertically, cell continuity is ensured at the boundary line between the upper side and the lower side. In and, a repeatable amorphous cell pattern in which cell patterns are continuous is prepared. In this way, if the cell pattern is repeatable, even if there is a conduit cross section having a width exceeding the image width YL, mapping is performed by arranging a plurality of cell patterns vertically. In this way, cell mapping without discomfort is possible.

In order to create such a repeatable amorphous cell pattern, the following may be done. First, by the above-mentioned method, the mother points are randomly arranged in a predetermined image area to define one mother point dispersion plane.
Subsequently, two more planes exactly the same as this mother point dispersion plane are defined, and a total of three totally same mother point dispersion planes are arranged adjacent to each other in the vertical direction. In other words, three planes having exactly the same mother point arrangement are arranged in the vertical direction. Then, a Voronoi diagram is created for all of these three generating points distribution planes. Finally, if only the central plane is taken out of the three planes, the Voronoi diagram formed on this plane becomes a repeatable amorphous cell pattern in which the cell patterns are continuous on the upper side and the lower side.

[0067]§3. A wood grain conduit according to an embodiment of the present invention
Cross-section pattern forming device  Finally, a wood-grain conduit cross-section pattern for performing the method described above.
An example of a turn forming device is shown. FIG. 25 shows such
It is a block diagram which shows the basic composition of one Example of an apparatus. This
In the device, the parameter input means 1, the random number generation means 2, the mother
Point placement means 3, Voronoi diagram creation means 4, image input means
5, image synthesizing means 6 and image output means 7
You. However, this block diagram shows the configuration of this device.
Although shown as a functional block, this device is actually
Is realized using a computer, and each functional block
I / O devices connected to the computer and computer
It is realized by software for data.

The parameter input means 1 is means for inputting each parameter input in step S11 of FIG. Actually, in addition to the parameters shown in step S11, the dimension values such as the width of the outer shell forming the irregular cell pattern to be created are also input as parameters.
The random number generation means 2 is a component for generating the random number RND used in step S16 of FIG. 22, and as described above, generates the random number between 0 and 1. The generatrix arrangement will be randomized based on this random number,
The reason why the cells constituting the finally obtained cell pattern are indefinite is because the generating points are arranged using this random number.

The mother point arrangement means 3 is means for arranging the mother points on the XY plane based on the algorithm shown in FIG. 22, and uses the random numbers generated by the random number generation means 2 to input the parameter input means 1 A process of randomly arranging mother points on the XY plane is performed at a predetermined density indicated by the parameter input to. The Horonoi diagram creating means 4 is a means for performing a process of creating a Voronoi diagram with the mother points arranged in this way as a nucleus. The principle of creating the Voronoi diagram is as described in §1.

The image input means 5 is means for inputting image data having information on the contour line of the cross section of the wood grain conduit, and is constituted by, for example, a scanner device. In this embodiment, a wood grain conduit cross-sectional pattern as shown in FIG. 4 is input as binarized raster image data. The image synthesizing means 6 is provided inside the individual conduit cross section indicated by the image data input from the image inputting means 5,
It is a means for performing a combining process for mapping the irregular cell pattern created by the Voronoi diagram creating means. This image composition process can be performed by a simple graphic logic operation. For example, in the first image data indicating the wood grain conduit cross-section pattern input from the image input means 5, the pixels existing inside the individual conduit cross sections have the pixel value "1", and the pixels existing outside have the pixel value ". The second image data, which is represented in the format of the raster image data taking 0 ", and which shows the irregular cell pattern created by the Voronoi diagram creating means 4, is a pixel forming the outer core part of each cell. Has a pixel value of "1", and the pixels forming the inside of the cell have a pixel value of "0". In this case, the image synthesizing unit 6 may superimpose the two images and perform a process of setting a logical product of the pixel values of the two images as a new pixel value. By such processing,
A raster image as shown in FIG. 13 will be obtained.

The image output means 7 is means for outputting the combined image as a wood grain conduit cross-section pattern. Specifically, the image data is output to an external storage device such as a hard disk, or the image data is output to a plate machine or the like.

[0072]

As described above, according to the present invention, it becomes possible to express a wood grain conduit cross-sectional pattern having a texture close to that of nature by a simpler method.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of a wood grain conduit cross-sectional pattern appearing on a timber board of general natural wood.

FIG. 2 is an enlarged view of a circular portion area W of the pattern shown in FIG.

FIG. 3 is a diagram illustrating a depth distribution of a conduit groove obtained when a general natural tree is cut.

FIG. 4 is a more detailed view showing an example of a wood grain conduit cross-section pattern that appears on an actual natural wood lumber board.

FIG. 5 is a cross-sectional view showing an example in which an embossed structure is formed on the embossing plate 10 by using information on the contour line of the planar wood grain conduit cross section P.

6 is a cross-sectional view showing the structure of an embossed wood grain print 20 using the embossing plate 10 shown in FIG.

FIG. 7 is a diagram showing an example of an amorphous cell pattern used in the present invention.

FIG. 8 is a plan view showing a state in which the irregular cell pattern shown in FIG. 7 is mapped inside one cross section of a wood grain conduit.

FIG. 9 is a cross-sectional view showing an example in which an uneven structure is formed on the embossing plate 15 by using the information of the cross section of the wood grain conduit to which the amorphous cell pattern is mapped according to the present invention.

10 is a cross-sectional view showing the structure of an embossed wood grain print 25 using the embossing plate 15 shown in FIG.

FIG. 11 is a diagram showing another example of an amorphous cell pattern used in the present invention.

FIG. 12 is a graph showing the distribution of the average area S of cells forming the irregular cell pattern shown in FIG. 11.

FIG. 13 is a plan view showing a state in which the amorphous cell pattern shown in FIG. 11 is mapped inside the cross section of a wood grain conduit.

FIG. 14 is a diagram showing a state where six mother points M1 to M6 are defined on a plane.

FIG. 15 is a diagram showing Voronoi polygons showing the influence zones of each generating point shown in FIG. 14;

FIG. 16 is a diagram showing an example in which regular generating points Mi are defined as the vertices of an equilateral triangle that fills a plane.

17 is a diagram showing a Voronoi diagram created based on the generating points Mi arranged regularly as shown in FIG. 16;

FIG. 18 is a diagram showing an example of a method of defining a distance between a generating point M and an arbitrary point Q defined when creating a Voronoi diagram.

FIG. 19 is a diagram showing “four adjacent pixels” and “eight adjacent pixels” with respect to a predetermined pixel Q.

FIG. 20 is a diagram for explaining “four adjacent distances” or “eight adjacent distances”.

FIG. 21 is a flow chart showing a procedure of a method for forming a wood grain conduit cross-sectional pattern according to an embodiment of the present invention.

22 is a flowchart showing a specific procedure of the process of randomly arranging generating points shown in step S2 of the flowchart of FIG.

FIG. 23 is an expected area E of cells and a population density D of cells to be defined in executing the procedure shown in the flowchart of FIG. 22;
5 is a graph showing the distribution of the X axis.

FIG. 24 is a diagram showing an example of an image area set by the procedure shown in the flowchart of FIG. 22.

FIG. 25 is a block diagram showing a basic configuration of a device for forming a cross section pattern of wood grain conduit according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Parameter input means 2 ... Random number generation means 3 ... Generating point arrangement means 4 ... Voronoi diagram creation means 5 ... Image input means 6 ... Image combining means 7 ... Image output means 10 ... Embossing plate 11 ... Convex part 12 ... Slit 15 ... Embossed plate 20 ... Wood pattern print 21 ... Recess 22 ... Partition wall 25 ... Wood pattern print C, C1, C2, C3 ... Cut surface D ... Mother point density E ... Expected cell area G ... Conduit groove Hi ... Regular hexagonal Voronoi Polygon L ... Longitudinal direction L1, L2, L3 ... Length in the longitudinal direction of the cross section of the wood grain conduit M1 to M6, Mi ... Mother point P, P1, P2, P3 ... Cross section of the wood grain conduit Q ... Arbitrary point (pixel) S ... Average area of cell T ... Conduit W ... Circular partial area XL ... Image length YL ... Image width

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Futa Miki 1-1-1, Ichigaya Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Tetsuo Shinki 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1 Dai Nippon Printing Co., Ltd. (72) Inventor Yu Okamoto 1-1-1, Ichigaya Kagamachi, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd

Claims (9)

[Claims] 1. A cross section of a wood grain conduit obtained by cutting a natural wood having a large number of conduits at a predetermined cutting plane is pseudo-expressed, and a cell pattern is formed inside each individual conduit cross section. Prints, embossing products, printing plates, and embossing plates with a characteristic wood grain conduit cross-section pattern. 2. The printed matter, the embossed product, the printing plate, and the embossed plate according to claim 1, wherein the cell pattern formed inside the individual conduit cross section is an irregular cell pattern in which the shape of each cell is not constant. A printed matter, an embossed product, a printing plate, and an embossed plate having a wood grain conduit cross-section pattern characterized by being present. 3. The printed matter, the embossed product, the printing plate, and the embossed plate according to claim 1 or 2, wherein the cell pattern formed inside each individual conduit cross section monotonically increases in the longitudinal direction of the conduit cross section. Printed matter, embossed products, printing plates, and embossed plates having a wood grain conduit cross-section pattern, characterized in that they are composed of a large number of cells having an average area. 4. A method for forming a wood grain conduit cross-section pattern, which is a pseudo representation of a wood grain conduit cross section obtained by cutting a natural wood having a large number of pipes at a predetermined cutting plane, wherein a contour line of the wood grain conduit cross section is formed. A first step of preparing first image data having information, a second step of defining a large number of generating points randomly arranged on a plane, and a Voronoi diagram having the generating points as cores Then, the third step of preparing the second image data having the information of the amorphous cell pattern represented by this Voronoi diagram, and the mapping of the amorphous cell pattern in each conduit cross section. A fourth step of synthesizing the first image data and the second image data to form a wood grain conduit cross-section pattern consisting of a large number of conduit cross-sections having an indeterminate cell pattern. Wood conduit cross pattern formation method characterized by having a wood grain conduit cross pattern, a fifth step of outputting the image. 5. The method according to claim 4, wherein in the first step, a natural wood board obtained by cutting a natural wood having a large number of conduits at a predetermined cutting surface is used, and the natural wood board appears on the surface of the natural wood board. By taking in the actual wood grain conduit cross-section pattern as image data by an optical method,
A method for forming a cross-sectional pattern of a wood grain conduit, which comprises preparing image data of. 6. The method according to claim 4 or 5, wherein in the second step, generating points are randomly arranged on the XY plane so that the generating point density monotonically decreases along the X-axis direction, In the third step, based on the mother points arranged on the XY plane, the second image data showing an irregular cell pattern in which the average area of each cell monotonically increases along the X axis is generated.
It is prepared on the Y plane, and in the fourth step, indefinite cell patterns are mapped in the cross sections of the individual conduits in such a state that the longitudinal direction thereof and the X-axis direction in the second image data substantially coincide with each other. As described above, the method of forming a wood grain conduit cross-sectional pattern, characterized in that the first image data and the second image data are combined. 7. The method according to claim 6, wherein in the second step, a maximum density and a minimum density of the generating points are defined,
By defining the random arrangement of the mother points that monotonically decreases from the maximum density to the minimum density in the section of length XL along the X axis for each of the n lengths XL, there are n kinds of mother point arrangements. In the third step, n kinds of irregular cell patterns each having an image length XL are prepared based on the n kinds of mother point arrangements, and in the fourth step, each conduit cross section is prepared. A method for forming a cross-section pattern of wood grain conduits, characterized in that image synthesis is performed so that an irregular cell pattern having an image length XL corresponding to the length in the longitudinal direction is selectively mapped. 8. A device for forming a wood grain conduit cross-section pattern, which is a pseudo representation of a wood grain conduit cross section obtained by cutting a natural wood having a large number of conduits at a predetermined cutting plane, and a parameter for inputting a predetermined parameter. An input means; a random number generating means for generating a random number; a generating point allocating means for randomly generating generating points on the XY plane at a predetermined density indicated by the parameter using the random numbers; Voronoi diagram creating means for creating a Voronoi diagram as a core, image input means for inputting image data having information on the contour line of the cross section of the wood grain conduit, and the Voronoi inside the individual conduit cross section indicated by the image data. An image synthesizing unit that performs a synthesizing process that maps the irregular cell pattern represented by the figure, and the image after synthesizing is used as a wood grain conduit cross-sectional pattern. Forming apparatus wood grain conduit section pattern and having and an image output unit for outputting. 9. The apparatus according to claim 8, wherein the generating point placement means has a function of randomly setting generating points on the XY plane so that the generating point density monotonically decreases along the X-axis direction. Then, the Voronoi diagram creating means creates a Voronoi diagram showing an irregular cell pattern such that the average area of each cell monotonically increases along the X axis, based on the generating points arranged on the XY plane. And the image synthesizing means has a function of performing mapping in each section of the conduit in a state where the longitudinal direction of the section and the X-axis direction of the amorphous cell pattern substantially match each other. Forming equipment.