JP5099638B2 - True / false discrimination printed matter - Google Patents

Description

  The present invention relates to a true / false discrimination printed matter in which a latent image having a printed pattern composed of density steps (hereinafter referred to as “gradation”) from highlight to shadow is embedded in the printed matter.

  Anti-counterfeiting technology is applied to valuable items such as banknotes, passports, securities, cards, stamps, product tags, toll road tickets, and various valuable tickets to guarantee and maintain their value. Therefore, a special print pattern is applied to such valuables. By overlaying a discriminator consisting of a line filter and a discriminator consisting of a lenticular lens on the printed pattern, the latent image is visually recognized and False discrimination is performed.

  For example, as a technique for discriminating authenticity with a discriminator composed of a line filter, a visible image portion printed with a line drawing line (referred to as an area that is not a latent image portion described later) is different from a visible image portion The latent image portion is printed with the angled line, and at first glance, the visible image portion and the latent image portion are difficult to see, but the line filter is superposed on the printed matter at a predetermined angle. Then, a technique is known in which a visible image portion and a latent image portion are separated and visually recognized.

  As an example, the printed material on which the pattern modulated in the first direction and the second direction is formed, and the first direction of the printed material coincides with the direction of the line pattern of the line filter. If the angle at which the first multi-tone image formed by superimposing the line filters is overlapped with the second direction of the printed matter is changed to the second multi-tone image formed by superimposing the line filters. There is a printed matter and an image forming method characterized in that a multi-tone image is formed (see, for example, Patent Document 1).

  In addition, as a technique for determining authenticity by a discriminator composed of a lenticular lens, n is a predetermined integer of 2 or more, and a band is formed by the first to n bands arranged in parallel in the order of the first to n. A printed matter that forms an image with a plurality of the bands, and selects two of the first to n bands as a band to exclusively paste a region corresponding to the band of the first predetermined image, A hidden image is revealed by superimposing a lenticular lens on a printed matter in which an image formed by changing the pasting band from the selected one band to the other band in the contour is printed. A printed matter is disclosed (for example, see Patent Document 2).

  Further, as the authenticity printed matter using halftone dots, a gradation image is formed by a background image portion and a latent image portion, the background image portion is formed by a first halftone dot, and the latent image portion is There is disclosed a printed matter that is formed by second halftone dots and is capable of authenticating whether the first halftone dots and the second halftone dots are different (for example, see Patent Document 3).

Japanese Patent Laid-Open No. 10-230684 JP 2003-094790 A JP 2007-144671 A

  However, in Japanese Patent Laid-Open No. 10-230684, it is necessary to make the line pitch of the line filter substantially equal to the pitch of the line pattern forming the printed matter, and the pitch width of the line filter is limited. Further, the line filter is blocked by the line part of the line line, and the latent image part is not clearly visible.

  Japanese Patent Laid-Open No. 2003-094790 discloses that a latent image portion that becomes a hidden image and its surrounding visible image portion are composed of line drawings, or a latent image portion that becomes a hidden image and its surrounding visible image portion. Is composed of lines drawn by halftone dots and has a misalignment in the arrangement of lines in the latent image portion and the visible image portion. Therefore, even when only the printed matter is observed, the latent image portion and the visible image portion There was a problem that the border was visible with the naked eye. Furthermore, since the printed matter is composed of misaligned lines, it is difficult to embed a latent image in a printed matter having gradation, and when embedding a plurality of latent image images, the gradation of the printed matter itself is difficult to embed. There was a problem that the reproducibility of was reduced.

  In either of Japanese Patent Laid-Open Nos. 10-230664 and 2003-094790, a latent image cannot be confirmed unless the discriminating tool is completely matched at a predetermined position. Does not appear, the authenticity discrimination effect is low.

  Japanese Patent Application Laid-Open No. 2007-144671 discloses that since the shape of the first halftone dot constituting the background image portion and the shape of the second halftone dot constituting the latent image portion are different, the authenticity determination printed matter has a lens. In the case where the sheet is used while being tilted while being stacked, the expression of the interference pattern of the first halftone dot shape and the second halftone dot shape may become unclear.

  The present invention proposes a true / false discrimination printed material for the purpose of solving such a conventional problem.

  The present invention is a true / false discrimination printed matter in which a gradation image is formed by regularly arranging a plurality of halftone dots on at least a part of a base material, and the gradation image is obtained from a first shape. A first halftone dot group in which the first halftone dots are arranged in a first direction at a first pitch, and the first halftone dot group is further arranged in the second direction in the first pitch. And a second halftone dot group in which a plurality of visible image portions arranged at the same pitch and a second halftone dot having the second shape are arranged at the same pitch as the first pitch in the first direction. And the second halftone dot group further includes a latent image portion formed by arranging a plurality of second halftone dot groups in the second direction at the same pitch as the first pitch. The halftone dots 2 have the same area, and the second shape is different from the first shape in that part of the fine shape is different from the latent image. An image is formed, and the first halftone dot group and the second halftone dot group are arranged with the first pitch on the same line in the first direction, and the authenticity determination printed matter When the discriminating tool composed of a lens group having the same pitch as the first pitch is overlaid in the first direction, the latent image is visually recognized, and the discriminating tool is overlaid from the first direction. When the printed material is slid and tilted, the first and second shapes are synthesized and visually confirmed to be printed.

  In the present invention, the first halftone dot is formed by a halftone dot matrix of m × m pixels (m ≧ 3, m is an integer), and the second halftone dot is m × m pixels (m ≧ m 3 and m are integers), and the first shape and the second shape are true / false discrimination prints having the same number of pixels.

  Further, in the present invention, it is a true / false discrimination printed matter formed by visually reversing the latent image when the discriminator is shifted from the first direction to the second direction while being overlapped.

  The printed material for authenticity determination of the present invention can confirm a latent image when the discriminating tool is overlapped at a predetermined position, and when the discriminating tool is slid on the printed material with the discriminating tool overlaid from the predetermined position, interference Since the image can be confirmed, two different virtual images can be confirmed, and the authenticity determination can be performed with the two different virtual images. Therefore, the present invention can be applied to a valuable printed matter that requires the authenticity determination. The interference pattern has the same area as the first halftone dot shape and the second halftone dot shape, and since the shape is approximate, a clear interference pattern can be visually recognized.

  In addition, the authenticity determination printed matter of the present invention has different effects when observing a latent image with a lenticular lens and a microlens array sheet. When observing with a lenticular lens, only the latent image can be confirmed. When observed, the latent image switching effect from the interference pattern expression to the latent image expression is obtained, and a higher authenticity discrimination effect is obtained.

  In the true / false discrimination printed matter according to the present invention, the first halftone dot and the second halftone dot, in which the density is changed stepwise from the darkest color to the thinnest color, are opposed to each other in each gradation. Since the areas of the halftone dots and the second halftone dots are the same and some of the fine shapes are different from each other, there is no possibility that the boundary between the latent image portion and the visible image portion can be visually recognized.

  The best mode for carrying out the present invention will be described with reference to the drawings. However, the present invention is not limited to the best mode for carrying out the invention described below, and various other embodiments are included within the scope of the technology described in the claims.

  FIG. 1 is an example of the authenticity determination printed matter P1 of the present invention. As shown in FIG. 1, the authenticity determination printed matter P1 is provided with a printed pattern (2) on a substrate (1), and the printed pattern (2) includes a visible image portion (3) and a latent image portion (4). It is the composition which includes. Further, the latent image portion (4) is included in the visible image portion (3). As shown in FIG. 1, the printed pattern (2) is a pattern of “ship” having gradation, and the latent image portion (4) is formed with the number “1” formed in the printed pattern (2). Yes. In the drawing, “1” of the latent image portion (4) can be recognized, but “1” of the latent image portion (4) cannot actually be recognized with the naked eye. The visible image portion (3) is a region around “1” of the latent image portion (4), and is a region that is not a latent image portion in the printed pattern (2).

  Next, the first halftone dot forming the visible image portion (3) and the second halftone dot forming the latent image portion (4) will be described. FIG. 2A shows, as an example, a first halftone dot (A) in which a character “A” (a configuration in which no pixel exists) has a first shape. The gradation of the first halftone dot (A) is expressed by the presence or absence of pixels around the character “A”. For example, in a dark color with a gradation of 48, pixels exist around the entire character “A”. Further, the intermediate color having a gradation of 24 has fewer pixels than the dark color. Further, in the light color whose gradation is 1, pixels exist only around the character “A”. On the other hand, as an example of FIG. 2B, the latent image portion (4) is a second halftone dot (B) in which the character “A” (configuration in which no pixel exists) has a second shape. The gradation of the second halftone dot (B) is expressed by the presence or absence of pixels around the character “A”. For example, in a dark color with a gradation of 48, pixels exist around the entire character “A”. Further, the intermediate color having a gradation of 24 has fewer pixels than the dark color. Further, in the light color whose gradation is 1, pixels exist only around the character “A”.

  Next, the relationship between the first halftone dot (A) and the second halftone dot (B) will be described. As shown in FIG. 3, the first halftone dot (A) and the second halftone dot (B) have the same gradation in order to make the gradations correspond to each other. For example, A48 of the first halftone dot (A) with a gradation of 48 is made to correspond to the gradation of the corresponding second halftone dot (B) with B48 having the same gradation as A48. Further, the gradation of the first halftone dot (A) having the gradation of 24 as the intermediate color is made to correspond to the gradation of the corresponding second halftone dot (B) with B24 having the same gradation as A24. It should be noted that the gray level of the first halftone dot (A) whose gray level is 1 is made to correspond to the gray level of the corresponding second halftone dot (B) with B1 having the same gray level as A1.

  Next, the first halftone dot (A) and the second halftone dot (B) will be described. The first halftone dot (A) and the second halftone dot (B) are expressed by the presence / absence of pixels in the halftone dot matrix (5) comprising a matrix of m × m (m is an integer). FIG. 4 shows, as an example, a halftone dot matrix composed of a 16 × 16 matrix. The gradation is expressed by the abundance of pixels in the halftone matrix (5). Note that the “pixel” in this specification refers to an “image element” in which the minimum portion of the halftone dot matrix (5) that is finely divided is represented by binary values.

  Next, the relationship between the halftone dot matrix (5) and the pixels in the first halftone dot (A) and the second halftone dot (B) will be described. FIG. 5A shows a change in gradation from a light color to a dark color of the first halftone dot (A) in which the character “A” (configuration in which no pixel is present) has a first shape. As shown in FIG. 5A, in the case of a light color with a gradation of 1, the pixel exists only around the character “A” in the halftone dot matrix (5), and therefore, it is expressed as a light color A1. Is done. A dark color having a gradation of 48 is expressed as A48 which is a dark color because pixels exist in the whole halftone dot matrix (5) other than the character “A”.

  On the other hand, FIG. 5B shows a change in gradation from a light color to a dark color of the second halftone dot (B) in which the character “A” (configuration in which no pixel exists) has the second shape. is there. As shown in FIG. 5B, in the case of a light color with a gradation of 1, the pixel is present only around the character “A” in the halftone dot matrix (5), so that it is expressed as a light color B1. Is done. In the case of a dark color with a gradation of 48, pixels exist in the entire halftone dot matrix (5) other than the character “A”, so that it is expressed as a dark color B48.

  Next, the first shape of the first halftone dot (A) and the second shape of the second halftone dot (B) will be described. As shown in FIG. 6A, the first shape of the first halftone dot (A) and the second shape of the second halftone dot (B) are made up of white letters “A”. Shape. However, as shown in the enlarged view of FIG. 5B, the second halftone dot (B) is second with respect to “A” which is the first shape (a) of the first halftone dot (A). The shape (b) of “A” is different in fine portions.

  Next, the shape of the first halftone dot (A) and the second halftone dot (B) will be described in detail based on the coordinates of the halftone dot matrix (5). FIG. 7A is an enlarged view of “A”, which is the first shape (a) of the first halftone dot (A), and shows coordinate values in which no pixel exists in the first shape (a). ing. “A” which is the first shape (a) has coordinates (5, 6), (5, 7), (6, 7), (6, 8), (6, 9) of the halftone dot matrix (5). ), (7, 8), (7, 10), (7, 11), (8, 8), (8, 12), (8, 13), (9, 8), (9, 12), (9,13), (10,8), (10,10), (10,11), (11,7), (11,8), (11,9), (12,6), (12 , 7) in which 22 pixels do not exist.

  FIG. 7B is an enlarged view of “A” that is the second shape (b) of the second halftone dot (B), and the second shape (b) shows coordinate values where no pixel exists. ing. The second shape (b) “A” is the coordinates (5, 6), (5, 7), (6, 7), (6, 8), (6, 9) of the halftone dot matrix (5). ), (7, 7), (7, 10), (7, 11), (8, 7), (8, 12), (8, 13), (9, 7), (9, 12), (9, 13), (10, 7), (10, 10), (10, 11), (11, 7), (11, 8), (11, 9), (12, 6), (12 , 7) in which 22 pixels do not exist.

  The number of pixels constituting “A” as the first shape (a) and the number of pixels constituting “A” as the second shape (b) are both 22 and are the same. Therefore, the areas of the first shape (a) and the second shape (b) are the same. The first shape (a) and the second shape (b) are (5, 6), (5, 7), (6, 7), (6, 8), (6, 9), ( 7,10), (7,11), (8,12), (8,13), (9,12), (9,13), (10,10), (10,11), (11, 7), (11, 8), (11, 9), (12, 6), and (12, 7) are configured so that pixels do not exist at the same coordinates, and the portions are the same. On the other hand, the finely different portions of the first shape (a) and the second shape (b) are (7,8), (8,8), (9,8) in the first shape (a). ), (10, 8), the pixel does not exist at the four coordinates, whereas the second shape (b) has (7, 8), (8, 8), (9, 8). , (10, 8) is a configuration in which pixels exist at four coordinates.

  The second shape (b) has a configuration in which no pixel exists at the four coordinates (7, 7), (8, 7), (9, 7), (10, 7). The first shape (a) is a configuration in which pixels exist at four coordinates (7, 8), (8, 8), (9, 8), and (10, 8). The fine differences between the first shape (a) and the second shape (b) are the four coordinates (7,8), (8,8), (9,8), (10,8). And the presence of four coordinate pixels (7, 7), (8, 7), (9, 7), and (10, 7). Therefore, the minute difference between the first halftone dot (A) and the second halftone dot (B) is a difference in a part of the coordinates where the pixels exist, and the total number of pixels is the same. Are the same.

  Further, the first halftone dot (A) and the second halftone dot (B) for forming the true / false discrimination printed matter of the present invention are not limited to the character having the shape “A”. The halftone dots (A) and the second halftone dots (B) should have the same area and have a finely different shape from the first shape, and halftone dots composed of characters, figures, symbols, etc. can be used. This is because the authenticity determination printed matter of the present invention develops a latent image due to a fine difference between the first shape of the first halftone dot (A) and the second shape of the second halftone dot (B).

  As an example, FIG. 8A shows the second shape of the second halftone dot (B) with respect to “A” that is the first shape of the English character at the first halftone dot (A). “A” is a shape in which the position of the horizontal line (horizontal bar) of “A” which is the first shape is slightly different. In FIG. 8B, the second halftone dot (B) is “鳳凰”, which is the first shape of the first halftone dot (A). The shape of the wing is slightly different. FIG. 8C shows that “fish”, which is the first shape of the first halftone dot (A), has “fish”, which is the first shape, as the second halftone dot (B). The body has a slightly different shape. FIG. 8D shows the shape of the character composed of the Chinese character “dog” at the first halftone dot (A) and the character “dog” at the second halftone dot (B) where the position of the point is different. It is the shape which consists of. Therefore, although the first shape and the second shape are recognized as the same shape as a whole, a part of the shape is slightly different.

  In FIG. 8, the first halftone dot (A) and the second halftone dot (B) express gradations by the presence of pixels in the outer peripheral direction centering on white letters and the like. However, the present invention is not limited to this. For example, as shown in FIG. 9A, the shape of the fish is configured by pixels in the halftone dot matrix (5), and the pixels are stepped from the four corners of the halftone dot matrix (5) to the center direction from the outer peripheral direction. Configuration for generating, as shown in FIG. 9B, a configuration for generating pixels in stages from the four corners and both ends, lower right, lower left, etc. of the halftone matrix (5) in the center direction, FIG. 9C. As shown in FIG. 5, the halftone dot matrix (5) may be configured by the shape of an aggregate of polygonal pixels such as a circle and a rectangle.

  Next, the arrangement of the first halftone dots (A) that form the visible image portion (3) and the arrangement of the second halftone dots (B) that form the latent image portion (4) will be described. As shown in FIG. 10A, the first halftone dots (A) are arranged in the first direction at the first pitch to form the first halftone dot group (A ′), A visible image portion (3) is formed by arranging the first halftone dot group (A ′) in the second direction at the same pitch as the first pitch. Further, as shown in FIG. 10B, the second halftone dot (B) is arranged in the first direction at the same pitch as the first pitch, thereby forming the second halftone dot group (B ′). Then, a plurality of second halftone dot groups (B ′) are arranged at the same pitch as the second pitch in the second direction to form the latent image portion (4). The first direction, which is the arrangement direction of the first halftone dot (A) and the second halftone dot (B), is the same direction, and is an extension of the arrangement direction of the first halftone dot (A). The second halftone dot (B) is arranged. The pitch of the first halftone dot (A) and the second halftone dot (B) is the same. Further, the pitch of the first halftone dot group (A ′) and the second halftone dot group (B ′) is also the same, and the first halftone dot group (A ′) and the second halftone dot group (B ′). ) Are arranged on the same line.

  Next, the positional relationship between the first halftone dot (A) and the second halftone dot (B) will be described. As shown in FIG. 11 (a), the first halftone dots (A) forming the visible image portion are arranged at the same pitch (P) in the X direction and the Y direction, and the first halftone dot group ( A ′) is also arranged at the same pitch in the same direction. The second halftone dots (B) forming the latent image portion are also arranged in the X and Y directions at the same pitch (P) as the first halftone dots (A). The halftone dot group (B ′) is also arranged at the same pitch as the first halftone dot group (A ′). The interval between the first halftone dot (A) forming the visible image portion and the second halftone dot (B) forming the latent image portion is also arranged at the same pitch (P) in the X and Y directions. ing. In FIG. 11A, the first halftone dot (A) and the second halftone dot (B) are arranged in a straight line (the same line), but the first halftone dot (A) and the second halftone dot (B) The halftone dots (B) need only be arranged at the same pitch (P) in the X and Y directions, as shown in FIG. 11 (b). The arrangement position may be shifted by half a pitch in rows in the X direction, or may be shifted by a half pitch in columns in the Y direction.

  FIG. 12 is a diagram showing the authenticity determination printed matter P1 of the present invention and a partially enlarged view thereof. As shown in the enlarged view of FIG. 12, the visible image portion (3) is configured by arranging the first halftone dots (A) shown in FIG. 5 (a) at the same interval of the pitch (P). Yes. The latent image portion (4) is also configured by arranging the second halftone dots (B) at the same pitch (P) as the first halftone dots (A).

  The authenticity determination printed matter P1 of the present invention shown in FIG. 12 creates a halftone screen with computer graphic (CG) software, and uses a half-tone image of “ship” as a background image. A screening process for replacing with a tone screen is performed to create a visible image portion and a latent image portion. The screening process is an operation for replacing density information of each pixel of the gradation image with a halftone screen having a corresponding area. The printing surface of the authenticity determination printed matter P1 of the present invention is divided into a latent image portion “1” and a visible image portion other than that (region other than the numeral 1), and the area of the latent image portion “1” is within the area. Replaced with the second halftone dot (B), the visible image portion (area other than the numeral 1) performs the process of replacing with the first halftone dot (A) to produce binary image data, and the plate surface is based on the data. Is made. The authenticity determination printed matter P1 of the present invention is manufactured by placing a printing plate prepared from binary image data on a printing press.

  When the authenticity determination printed matter P1 is observed with the naked eye under visible light, as shown in FIG. 13, the visible image portion (3) and the latent image portion (4) are separated and cannot be visually recognized. The pattern of “ship” in pattern (2) can be confirmed. This is because the area of the first halftone dot (A) for each gradation of the visible image portion (3) and the area of the second halftone dot (B) for each gradation of the latent image portion (4) are: This is because, since they are the same, the visible image portion (3) and the latent image portion (4) cannot be viewed separately.

  Next, a first state in which the lenticular lens (6) is superimposed on the authenticity determination printed matter P1 will be described. As shown in FIG. 14, the first state referred to here is coordinates in which no pixel exists at the first halftone dot (A) due to the lens portion of the line-shaped lenticular lens (6) (7 , 8), (8, 8), (9, 8), (10, 8) are enlarged, and the coordinates where the pixel exists at the second halftone dot (B) are (7, 8), In this state, four pixels (8, 8), (9, 8), and (10, 8) are enlarged. Therefore, in the first state, the coordinates of the first halftone dot (A) where no pixel exists in the coordinates of the second halftone dot (B) and the first halftone dot (A) are the same. The state of the coordinates of the second halftone dot (B) where the pixel exists is enlarged. The lens arrangement pitch of the lenticular lens (6) was arranged at the same pitch P as the first halftone dot (A) and the second halftone dot (B).

  In the first state, the first halftone dot (A) forming the visible image portion is placed on the coordinates (7, 8), (8, 8), ( 9,8) and (10,8) are magnified and observed. On the other hand, the second halftone dot (B) constituting the latent image portion is placed on the coordinates (7, 8), (8, 8), (9, 8), ( 10, 8) is observed magnified. The first halftone dot (A) is observed lighter than the second halftone dot (B) in which the coordinates where the pixel exists are enlarged because the coordinates where the pixel does not exist are enlarged. Therefore, the latent image can be confirmed based on the difference in density.

  Therefore, as shown in FIG. 15A, when the lenticular lens (6) is placed on the authenticity determination printed matter P1, as shown in FIG. 15B, the visible image portion (3) is displayed in the first state. Is generally viewed lighter than the latent image portion (4), and the latent image portion (4) is generally viewed darker than the visible image portion (3). The image “1” can be confirmed. Note that the latent image portion (4) is visually recognized in the first direction, which is the arrangement direction of the first halftone dot and the second halftone dot, with the overlapping position of the lenticular lens (6) on the authenticity determination printed matter P1. It can be visually recognized by adjusting the lens arrangement pitch of the lenticular lens (6).

  Next, the second state in which the lenticular lens (6) is superimposed on the authenticity determination printed matter P1 will be described. The second state referred to here is coordinates in which a pixel is present at the first halftone dot (A) in the lens portion of the line-shaped lenticular lens (6) as shown in FIG. , 7), (8, 7), (9, 7), (10, 7) are expanded, and the second halftone dot (B) has no coordinates (7, 7), In this state, four pixels (8, 7), (9, 7), and (10, 7) are enlarged. Therefore, in the second state, the coordinates of the first halftone dot (A) where the pixel exists in the coordinates of the same position of the second halftone dot (B) and the first halftone dot (A) The state where the coordinates of the second halftone dot (B) where no pixel exists is enlarged. The second state can be observed by shifting the lens arrangement pitch (P) of the lenticular lens (6) in the Y direction from the first state.

  In the second state, the first halftone dot (A) forming the visible image portion is placed on the coordinates (7,7), (8,7), ( 9,7) and (10,7) are magnified and observed. On the other hand, the second halftone dot (B) constituting the latent image portion is provided with coordinates (7,7), (8,7), (9,7) where no pixel exists by placing the lenticular lens (6). ), (10, 7) are magnified and observed. The first halftone dot (A) is viewed darker than the second halftone dot (B) in which the coordinates where the pixels do not exist are enlarged because the coordinates where the pixels exist are enlarged. Therefore, the latent image can be confirmed based on the difference in density.

  Accordingly, as shown in FIG. 17A, the pitch (P) of the lens arrangement of the lenticular lens (6) from the first state to the Y direction from the first state, that is, 1 (1), as shown in FIG. When shifted by about pixels, as shown in FIG. 17 (b), the visible image portion (3) is visually recognized as a whole darker than the latent image portion (4) in the second state. The image portion (4) is visually recognized lighter than the visible image portion (3), and the latent image “1” can be confirmed by this density difference. In the first state, the latent image portion (4) is viewed darker than the visible image portion (3), and in the second state, the latent image portion (4) is viewed lighter than the visible image portion (3). Therefore, the first state and the second state have a negative / positive relationship.

  Next, a case where the microlens array sheet is overlaid on the authenticity determination printed matter P1 will be described. The micro lens array sheet (hereinafter referred to as “lens sheet”) is a sheet having a lens effect in which a large number of micro hemispheres (micro lens array) made of a light-transmitting material are regularly arranged. Thus, like a lenticular lens, it is a medium that has a high visual effect by being laminated on a printed material or the like. In the lens sheet 7 shown in FIG. 18, the arrangement pitch of the microlens array is arranged at the same pitch P as the first halftone dot (A) and the second halftone dot (B).

  As shown in FIG. 19 (a), when the lens sheet (7) is superimposed on the authenticity determination printed matter P1, as shown in FIG. 19 (b), the visible image portion (3) is displayed in the first state. The latent image portion (4) is viewed as generally lighter than the latent image portion (4), and the latent image portion (4) is viewed as darker than the visible image portion (3). “1” can be confirmed. The lens sheet (7) has the same lens arrangement and pitch as the lenticular lens (6), and the principle of expression of the latent image portion (4) is the same as that of the lenticular lens (6) described above. Therefore, the expression principle of the latent image portion (4) by the lens sheet (7) is omitted.

  Further, as shown in FIG. 20A, when the lens sheet (7) is shifted from the first state to the Y direction by about the pitch (P) of the arrangement of the lens array on the authenticity printed matter P1, as shown in FIG. As shown in FIG. 20 (b), in the second state, the visible image part (3) is visually recognized darker than the latent image part (4), and the latent image part (4) is visible. It is visually recognized lighter than the image portion (3), and the latent image “1” can be confirmed by this density difference. Therefore, even when the lens sheet (7) is used, the same effect as that obtained when the lenticular lens (6) is stacked can be obtained.

  Further, as shown in FIG. 21A, when the lens sheet (7) is overlapped with the authenticity determination printed matter P1 in the state of the angle α from the first state, as shown in FIG. 21B. The interference pattern of the letter “A”, which is the first shape, which is expressed by combining a plurality of letters “A”, which is the first shape of the first halftone dot (A), with the lens sheet (7). The second shape of the second halftone dot (B) is the first shape and the interference pattern of the character “A” that is the second shape, which is expressed by combining a plurality of characters “A”. The interference pattern of the character “A” and the interference pattern of the character “A”, which is the second shape, are synthesized and can be observed. Furthermore, as shown in FIG. 21C, when the lens sheet (7) is rotated in the θ direction from the position of the angle α, the first halftone dot (A) the first shape and the second halftone dot The letter “A” which is the second shape of (B) is gradually enlarged and observed. In the case where the lens sheet (7) angle α is 0 degree, that is, in the first state, the letter “A” and the second halftone dot which are the first shape of the first halftone dot (A) The character “A”, which is the second shape of (B), disappears and the latent image “1” can be observed.

  In the above description, for example, the printed pattern is described as an image having gradation by the halftone dots shown in FIG. 5, but the present invention is not limited to this, and the printed pattern does not have gradation, It may be a uniform image. For example, the visible image portion (3) is formed only by the first halftone dot A48 shown in FIG. 5A, and the latent image portion (4) is formed only by the second halftone dot B48 shown in FIG. A printed pattern can be formed. Further, the visible image portion (3) is formed only by the first halftone dot A24 shown in FIG. 5B, and the latent image portion (4) is formed only by the second halftone dot B24 shown in FIG. A printed pattern can be formed. Further, the visible image portion (3) is formed only by the first halftone dot A1 shown in FIG. 5 (a), and the latent image portion (4) is formed only by the second halftone dot B1 shown in FIG. 5 (b). A printed pattern can be formed.

  The screen line number of the halftone dots of the true / false discrimination printed material of the present invention is 25 lpi to 175 lpi, and preferably 30 lpi to 120 lpi. When the number of screen lines is larger than 175 lpi, it becomes difficult to produce a printed matter having the halftone dot shape of the present invention. When the screen line number is smaller than 25 lpi, the halftone dot size of the shadow portion exceeds 1 mm, the halftone dot shape can be recognized with the naked eye, and the latent image portion and the visible image portion are separated with the naked eye. May be visible.

  The base material on which the printed material for authenticity discrimination of the present invention is printed is not particularly limited, such as paper, plastic, film, metal plate and the like.

  The printing method for printing the authenticity printed matter of the present invention is an offset printing method, gravure printing method, screen printing method, flexographic printing method, inkjet printer, laser printer, solid printing method, etc. Although not particularly limited, an offset printing method is preferable. Moreover, the printing ink to be used is not particularly limited, and a color fluorescent ink, an infrared absorbing ink, a magnetic ink, an optically changing ink such as pearl, and the like can also be used.

  Since the printed pattern and the latent image can be composed of at least one of letters, numbers, symbols, and patterns, the design is not particularly limited.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail using an Example, the content of this invention is not limited to the range of these Examples.

Example 1
In the first embodiment, as shown in FIG. 22A, image data of “morning glory” in the TIFF format (gray 256 levels) is used. The halftone dots used in this embodiment have a screen line number of 100 lpi, and the number of pixels in an area of 1/100 inch (254 μm) × 1/100 inch is 16 × 16 pixels. As shown in FIG. 22 (b), the second shape (b) of the second halftone dot (B) is the same as the first shape (a) of the first halftone dot (A). Only the left and right wings were different and created with the same area. The pitch (P) of the first halftone dots (A) forming the visible image portion and the pitch (P) of the second halftone dots (B) forming the latent image portion are the same pitch (P) of 254 μm. As shown in the enlarged view of FIG. 22A, they are regularly arranged in a matrix. In the latent image portion, the character “P” is constituted by the second halftone dot (B).

  Next, the different parts of the first halftone dot (A) and the second halftone dot (B) according to the coordinates of the halftone dot matrix (5) will be described in detail. FIG. 23 is an enlarged view of “鳳凰” which is the first shape (a) of the first halftone dot (A) and the second shape (b) of the second halftone dot (B). The difference between “鳳凰” being the first shape (a) and “鳳凰” being the second shape (b) is that the coordinates (1, 8) of the dot matrix of the first shape (a), (1,11), (2,7), (2,12), (3,13), (5,8), (5,9), (5,10), (5,11), (6 , 12), (12, 7), (13, 8), (14, 12), (15, 8), (15, 9), (15, 10), (15, 11) to 17 pixels This is a point that does not exist.

  On the other hand, the difference between the second shape (b) of the second halftone dot (B) and the “鳳凰” that is the first shape (a) is the coordinates of the halftone dot matrix of the second shape (b) ( 2,8), (2,9), (2,10), (2,11), (3,12), (4,8), (5,7), (11,12), (12, 8), (12, 9), (12, 10), (12, 11), (14, 13), (15, 7), (15, 12), (16, 8), (16, 11) This is a point where there are no pixels in 17 of.

  Next, a screening process, which is an operation for replacing the density information of each pixel of the gradation image with a halftone dot having a corresponding area, was performed. Since the halftone dots created in this embodiment are 48 gradations, the gradation of the gradation image to be screened is converted to 256 gradations, and the gradation of the same gradation as that of each pixel of the gradation image is obtained. Replaced with dots. The visible image portion (3) was replaced with the first halftone dot (A), and the latent image portion was replaced with the second halftone dot (B). After performing the screening process, a PS plate surface was prepared, and an authenticity determination printed matter P2 of Example 1 was prepared using an offset printing machine (color: magenta ink).

  When the authenticity determination printed matter P2 was observed with the naked eye under visible light, the visible image portion (3) and the latent image portion (4) could not be visually recognized as shown in FIG. On the other hand, as shown in FIG. 24 (b), the 254 μm lenticular lens (6) in the first state described above in the embodiment is applied to the authenticity determination printed matter P2, and the lenticular lens (6 ), The visible image portion (3) as a whole is more than the latent image portion (4) “P” as shown in FIG. 24 (c). It was faintly visible. On the other hand, “P”, which is the latent image portion (4), is visually recognized as being darker as a whole than the visible image portion (3), thereby confirming the characters of the latent image “P”.

  As shown in FIG. 25 (a), when the lenticular lens (6) of the authenticity determination printed matter P2 is shifted by about 100 μm in the vertical direction (Y direction), the 254 μm lenticular lens is shifted to FIG. 25 (b). As shown, the visible image portion (3) is generally darker than the latent image portion (4) by the second state described above in the embodiment, and the latent image portion (4) is As a whole, it was visually recognized lighter than the visible image portion (3), and an image obtained by inverting the negative and positive in the first state and the second state of the latent image “P” could be confirmed.

  Next, a case where the lens sheet 7 is placed on the authenticity determination printed matter P2 will be described with reference to FIG. The arrangement pitch of the microlens array of the lens sheet (7) was arranged at the same pitch P as the first halftone dot (A) and the second halftone dot (B). As shown in FIG. 26A, the lens sheet (7) was superimposed on the authenticity determination printed matter P2. As shown in FIG. 26 (b), in the first state where the lens sheets (7) were overlapped, the visible image portion (3) was visually recognized as a whole lighter than the latent image portion (4). In addition, the latent image portion (4) was confirmed to be darker overall than the visible image portion (3), thereby confirming the latent image “P”.

  In addition, as shown in FIG. 27A, when the lens sheet (7) is shifted to the authenticity determination printed matter P2 from the first state and the 254 μm lenticular lens is shifted about 100 μm in the vertical direction (Y direction), As shown in FIG. 27B, in the second state, the visible image portion (3) is visually recognized darker than the latent image portion (4), and the latent image portion (4) is visible. By visually recognizing lighter than the part (3) as a whole, negative / positive-inverted images in the first state and the second state of the latent image “P” could be confirmed.

  As shown in FIG. 28 (a), when the lens sheet (7) is overlapped with the authenticity determination printed matter P2 from the first state with the angle α being inclined by about 7 degrees, it is shown in FIG. 28 (b). As shown in the figure, the lens sheet (7) has the shape of “鳳凰”, which is an interference pattern of the first shape of the first halftone dot (A), and the second shape “of the second halftone dot (B). We were able to observe the shape of 鳳凰. In this embodiment, the inclination angle α of the lens sheet (7) is 7 degrees, but it may be about 1 to 10 degrees. As shown in FIG. 28C, when the lens sheet (7) is rotated from the position of the angle α in the θ direction from the first state, the first shape of the first halftone dot (A) is obtained. The shape of the “鳳凰” in the second shape of the “鳳凰” and the second halftone dot (B) is gradually enlarged, and the first halftone dot (A) and the second halftone dot (B) interfere with each other. As a result, it was impossible to distinguish minutely different wing parts, and the shape of the “鳳凰” could be observed. Further, when the angle α of the lens sheet (7) is 0 degree, that is, in the first state, the shape of “鳳凰” which is an interference pattern that is generated by combining the first shape and the second shape is formed. It disappeared and the latent image “P” could be observed.

(Example 2)
In the second embodiment, the image data of “car” having two gray levels (TIFF format) shown in FIG. 29A is used. For the first halftone dot (A) and the second halftone dot (B), an image as shown in FIG. 29B was created using CG software. Since the gradation image in this embodiment has two gradations, the halftone dots to be created are the first halftone dot (A1) in the highlight portion of the visible image portion (3) and the first halftone dot (in the shadow portion). Two types of halftone dots of A2) were used. In addition, two types of halftone dots, the second halftone dot (B1) and the second halftone dot (B2), were used for the highlight portion and the shadow portion of the latent image portion (4). Note that the output device in the second embodiment uses an image setter with an output resolution of 2540 dpi and a pitch of 250 μm. Accordingly, since the pixels constituting the halftone dot matrix are 25 × 25 pixels (250 / (25.4 / 2540) = 25), the first halftone dot (A) and the second halftone dot (B) are 25 A dot matrix of × 25 pixels was used. The first halftone dots (A) and the second halftone dots (B) are arranged in a regular staggered pattern as shown in the enlarged view of FIG. The minutely different portion is the horizontal line (horizontal bar) portion of the letter “A”, and since it has been described above, description of the dot coordinates is omitted.

  Next, a screening process is performed in which a halftone dot having the same gradation as that of each pixel of the two-gradation image is replaced. First, the portion of the gradation image in the visible image portion (3) where the pixel is painted black is replaced with the first halftone dot (A2), and the portion where the pixel is not painted is replaced with the first halftone dot ( Substituted for A1). In addition, the portion of the gradation image in the latent image portion (4) where the pixels are painted black is replaced with the second halftone dot (B2), and the portion where the pixels are not filled is replaced with the second halftone dot ( Substituted for B1). After the screening process, film output was performed with an image setter to produce a PS plate surface, and printing was performed with an offset printing machine (color: magenta ink) to produce a true / false discrimination printed material P3.

  When the authenticity determination printed matter P3 was observed with the naked eye under visible light, as shown in FIG. 31, the visible image portion (3) and the latent image portion (4) could not be viewed separately. On the other hand, as shown in FIG. 32, the lenticular lens (6) of 250 μm in the first state is placed on the authenticity determination printed matter P3, and the lines of the lenticular lens (6) are in the vertical direction with respect to the authenticity discrimination printed matter P3. In this case, the visible image portion (3) was visually recognized as a whole lighter than “P” which is the latent image portion (4). On the other hand, “P”, which is the latent image portion (4), is visually recognized as being darker as a whole than the visible image portion (3), thereby confirming the characters of the latent image “P”.

  Further, as shown in FIG. 33, when the lenticular lens (6) of the authenticity determination printed matter P3 is shifted in the vertical direction (Y direction) by a 250 μm lenticular lens by about 100 μm, as shown in FIG. According to the state, the visible image portion (3) is viewed darker overall than the latent image portion (4), and the latent image portion (4) is generally viewed as compared to the visible image portion (3). It was visually recognized lightly, and an image obtained by inverting the negative and positive in the first state and the second state of the latent image “P” was confirmed.

  As shown in FIG. 34 (a), when the lens sheet (7) from the first state is overlapped with the authenticity determination printed matter P3 at an angle α of about 9 degrees, it is shown in FIG. 34 (b). As shown, the letter “A” and the dot shape of the first halftone dot (A) and the second halftone dot (B) could be observed by the lens sheet (7). Further, as shown in FIG. 34 (c), when the lens sheet (7) is rotated from the position of the angle α in the θ direction from the first state, the first halftone dot (A) and the second halftone dot are displayed. The character “A” at the point (B) and the shape of the dot are gradually enlarged, and the first halftone dot (A) and the second halftone dot (B) interfere with each other so that the portion of the character “A” that is slightly different The distinction could not be made, and the letter “A” and the dot shape could be observed. In addition, when the angle α of the lens sheet (7) is 0 degree, that is, in the first state, the letter “A” and the dot which are interference patterns that are generated by combining the first shape and the second shape. Disappeared and the latent image “P” could be observed.

The top view of authenticity printed matter P1. The top view which shows the gradation of the 1st halftone dot (A) and the 2nd halftone dot (B). The top view which shows the relationship between a 1st halftone dot (A) and a 2nd halftone dot (B). The top view which shows a halftone dot matrix. The top view which shows the relationship between the pixel of the 1st halftone dot (A) and the 2nd halftone dot (B). The top view which shows the shape of the 1st halftone dot (A) and the 2nd halftone dot (B) The top view which shows the pixel coordinate of a 1st halftone dot (A) and a 2nd halftone dot (B). Plan view showing an example of the shape of a halftone screen The top view of the 1st halftone dot (A) and the 2nd halftone dot (B) showing each gradation formed in the halftone screen cell. The top view which shows the example of arrangement | positioning of a 1st halftone dot group (A ') and a 2nd halftone dot group (B'). The top view which shows the example of arrangement | positioning of a 1st halftone dot (A) and a 2nd halftone dot (B). The authenticity discrimination printed matter P1 and its partially enlarged view. FIG. 6 is an observation view of the authenticity printed matter P1 with the naked eye under visible light. The enlarged view which shows the 1st state of the authenticity determination printed matter P1. The top view which shows the 1st state of the authenticity determination printed matter P1. The enlarged view which shows the 2nd state of the authenticity determination printed matter P1. The top view which shows the 2nd state of the authenticity determination printed matter P1. The perspective view which shows a micro lens array sheet | seat (7). The top view which shows the 1st state by the microlens array sheet | seat (7) of the authenticity determination printed matter P1. The top view which shows the 2nd state by the microlens array sheet (7) of the authenticity determination printed matter P1. The top view which shows an example by the microlens array sheet | seat (7) of the authenticity determination printed matter P1. The authenticity determination printed matter P2 and a partially enlarged view thereof. The top view which shows the shape of a 1st halftone dot (A) and a 2nd halftone dot (B). The top view which shows the 1st state of the authenticity determination printed matter P2. The top view which shows the 2nd state of the authenticity determination printed matter P2. The top view which shows the 1st state by the microlens array sheet | seat (7) of the authenticity determination printed matter P2. The top view which shows the 2nd state by the microlens array sheet (7) of the authenticity determination printed matter P2. The top view which shows an example by the microlens array sheet | seat (7) of the authenticity determination printed matter P2. The top view of the 1st halftone dot (A) and the 2nd halftone dot (B) which comprise the authenticity determination printed matter P3. The authenticity determination printed matter P3 and its partially enlarged view. FIG. 10 is an observation view of the authenticity printed matter P3 with the naked eye under visible light. The top view which shows the 1st state of the authenticity determination printed matter P3. The top view which shows the 2nd state of the authenticity determination printed matter P3. The top view which shows an example by the micro lens array sheet | seat (7) on the authenticity determination printed matter P3.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Print pattern 3 Visible image part 4 Latent image image part 5 Halftone dot matrix 6 Lenticular lens 7 Micro lens array sheet P1, P2, P3 Authenticity discrimination printed matter A, A1, A2 1st halftone dot A '1st Halftone dot group a, a1, a2 first shape B, B1, B3 second halftone dot B ′ second halftone dot group b, b1, b2 second shape

Claims (3)

An authenticity printed matter in which an image is formed by regularly arranging a plurality of halftone dots on at least a part of a substrate,
The image includes a first halftone dot group in which first halftone dots having a first shape are arranged in a first direction at a first pitch, and the first halftone dot group further includes a first halftone dot group. A plurality of visible image portions arranged in the direction of 2 at the same pitch as the first pitch, and a second halftone dot of the second shape is formed at the same pitch as the first pitch in the first direction. A second halftone dot group is formed, and the second halftone dot group further includes a latent image portion formed by arranging the second halftone dot group in the second direction at the same pitch as the first pitch;
The first halftone dot composed of the first shape is formed by a halftone dot matrix of m × m pixels (m ≧ 3, m is an integer), and the second halftone dot composed of the second shape. Is formed by a dot matrix of m × m pixels (m ≧ 3, m is an integer),
The number of pixels of the first halftone dot and the number of pixels of the second halftone dot are the same;
The relationship between the positions of the pixels of the first halftone dots and the positions of the pixels of the second halftone dots is different from each other in the arrangement of a predetermined number of pixels.
The pixel having the different arrangement is intended by combining the first halftone dot composed of the first shape and the second halftone dot composed of the second shape when the discriminator is observed in an overlapping manner. Placed at the position where the virtual image appears,
The first halftone dot group and the second halftone dot group are arranged with the first pitch on the same line in the first direction,
If the superposed said determination device consisting of the first pitch and the same pitch lens group in the first direction of the authenticity discrimination printed matter, the latent image portion is visually recognized,
When the discriminating tool is laid on the printed material and tilted from the first direction, the first halftone dot having the first shape and the second shape having the second shape are used . An authenticity determination printed matter obtained by visually recognizing the intended virtual image in which the halftone dots are synthesized. The authenticity determination printed matter according to claim 1, wherein the image is a gradation image.   3. The authenticity determination printed matter according to claim 1, wherein the latent image is visually reversed with a negative / positive reversal when the determination tool is shifted from the first direction in the second direction while being overlapped. 4. .

Images