JP2009083157A - Image forming body and method for preparing it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming body applied to a valuable article requiring forgery prevention, authentication and copying prevention, and a method for preparing it. <P>SOLUTION: In the image forming body, the image of a latent image is formed of lines of recessed parts on a substrate, and when the substrate is observed by inclining the substrate, the image of the latent image with a gradation is confirmed. The image forming body is characterized in that the image of the latent image is divided into N pieces of regions (N is ≥3), and respective regions divided into N pieces are distributed into first line patterns, second line patterns..., and n-th line patterns (n is ≥3) of the recessed parts, and the first line patterns, the second line patterns..., and the n-th line patterns consists of difference in arranging direction of the line patterns, difference in line width of the line patterns, difference in pitch width of the line patterns, or combinations thereof on every line patterns. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an image forming body that is applied to valuables that require anti-counterfeiting, authenticity discrimination, and copy prevention such as banknotes, securities, passports, passports, gift certificates, cards, product tags or brand protection, and the like. It relates to a manufacturing method thereof.

  Valuables such as banknotes, securities, passports, passports, gift certificates, cards, product tags or brand protection are required to be difficult to counterfeit and tamper by nature. As a preventive measure, there is known a technique for performing authenticity discrimination so that a latent image can be recognized by observing these valuables at an angle. For example, the technique using the line of a recessed part is mentioned.

  As a technique for making the latent image appear by using the line of the concave portion, the latent image pattern such as letters and numbers and / or the peripheral portion of the pattern has a pitch width of 0.2 to 1 mm on the surface of the substrate. There are securities that are formed with line-shaped irregularities by coining, and the line-shaped irregularities that are substantially perpendicular to the line-shaped irregularities that form the latent image pattern are formed around the latent image pattern. It is disclosed (for example, see Patent Document 1).

  Furthermore, a latent image portion and a background portion composed of a line-shaped concave portion using a laser are formed on a laminate film such as a passport, and the lines of the latent image portion and the background portion are out of phase or at different angles. A valuable printed matter protected by the formed laminate film and a method for producing the same are disclosed (for example, see Patent Document 2).

JP 2002-154262 (page 1-4, FIGS. 1 and 2) Japanese Patent No. 3514291 (page 7, FIGS. 4, 5)

  In both Patent Document 1 and Patent Document 2, the latent image that appears in either case does not have continuous tone, and there is a problem that it is difficult to adopt a complicated design as the latent image. Furthermore, since the arrangement of the recess lines is simple, there is a risk of forgery. Further, there is a drawback that the latent image can be seen even when observed from directly above the substrate. Furthermore, since the line is composed of a vertical direction and a horizontal direction, there is a problem that forgery can be easily performed.

  Since Patent Document 1 has line-shaped irregularities on the base material by embossing, it requires equipment and know-how to produce an embossing plate surface, and further requires a device that presses the embossing plate surface against the base material. As a result, the equipment was expensive, and it took a lot of time to prepare it.

  Patent Document 2 limits the base material to a film, not paper, but the film has high light reflectivity, and the light reflectivity between the film surface and the line-shaped groove is different. Even when viewed from directly above, the latent image is easy to visually recognize, and although the effect against tampering in which the film is peeled off and reused is high, the effect as a latent image is low.

  The present invention aims to solve such a conventional problem, and is a forgery prevention technique obtained only with a base material. The arrangement structure of the lines of the recesses is not simple. It is an object of the present invention to propose an image forming body having continuous gradation and capable of adopting a complicated design and a method for manufacturing the image forming body.

  The present invention provides an image forming body in which a latent image is formed by a line of a concave portion on a substrate, and a latent image having a gradation can be confirmed when the substrate is tilted and observed. N is divided into three or more areas, and each of the N divided areas is divided into a first line, a second line,..., An nth line (n is 3 or more). The first line, the second line, ... the nth line is assigned to each line, the difference in the arrangement direction of the lines, the difference in the line widths of the lines, the pitch width of the lines The image forming body is characterized by comprising a difference or a combination thereof.

  The image forming body of the present invention is characterized in that the line width of the concave portions of the line is 30 to 500 μm and the pitch width is in the range of 70 to 2000 μm.

  Further, the present invention provides a latent image in a method for producing an image forming body in which a latent image is formed on a base material by a line of a concave portion, and a latent image having a gradation can be confirmed when the base material is tilted and observed. The process of acquiring latent image data that is a collection of pixels in which density values are defined as the original image of the image, and the acquired latent image data are associated with each density and the array direction of each line. Conversion to lines with different arrangement directions for each density area of the latent image data based on the conversion table, and defining line width and pitch to generate line latent image data. This is a method for producing an image forming body comprising a step of forming a latent image on the surface of a material by means of concave lines based on line latent image data.

  In the image forming body of the present invention, the appearing latent image is excellent in gradation expression and can be expressed as a fine image. Since a complicated design having continuous gradation can be adopted, the design is not limited.

  The image forming body of the present invention is excellent in the anti-counterfeiting effect because the latent image is formed on the base material by a special machine such as a laser processing machine, using concave lines having a complicated arrangement direction.

  In addition, the image forming body of the present invention can confirm a latent image when observed by tilting from the vertical direction to the horizontal direction, and the latent image is confirmed as a positive latent image or a negative latent image depending on the observation direction. Therefore, it is possible to determine whether the latent image is present or not and whether the negative / positive is changed or not. Accordingly, it is possible for anyone to make a true / false determination based on whether or not the above-mentioned effect can be obtained on the spot without using a determination tool, a special authenticity determination device, or the like.

  Since the concave line forming the image forming body of the present invention can be produced by a laser, different information (variable information) can be individually formed on the valuables.

  From the above, the image forming body of the present invention has a high authenticity discrimination effect and has an anti-duplication effect because it is formed in a fine shape, such as banknotes, securities, passage tickets, passports, gift certificates, cards, It can be applied to product tags or brand protection.

  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 technical idea described in the scope of claims.

(Image forming body)
The line of the recessed part which has the predetermined width W which is the structure of this invention is demonstrated using FIG. As shown in FIG. 1, the concave line 5 having a predetermined width W is formed lower than the height of the base on the surface of the substrate 1. The predetermined width W is a width formed on the surface of the substrate 1 and is not a width in the depth direction. The cross-sectional shape of the line 5 of the recess having the predetermined width W is a triangular shape as shown in FIG. 1 (a), a trapezoidal shape as shown in FIG. 1 (b), a rectangular shape as shown in FIG. Examples include a bowl shape as shown in FIG. 1D and a right triangle shape as shown in FIG. However, the cross-sectional shape of the recess line 5 which is the configuration of the present invention is not limited to FIG. 1A to FIG. 1E, and for example, FIG. 1A to FIG. Alternatively, it can be formed in other cross-sectional shapes.

  FIG. 2 is a diagram divided into 13 regions 3 for each part forming the latent image 2 serving as a motif (original image) and / or for each lightness of the color forming the latent image 2. In the image forming body of the present invention, the first line, the second line, the third line, or the fourth line of the recess that is not penetrating the substrate in each of the 13 areas 3 is divided. 1 line, 2nd line, 3rd line, and 4th line are divided into the line direction of each line, the line width of the line It is formed by a difference, a difference in pitch width of the lines, or a combination thereof.

  When light is irradiated from a predetermined angle to the concave line in this case, the amount of reflected light from the first line, the second line, the third line, and the fourth line is 1 million line> 2nd line> 3rd line> 4th line, or 1st line <2nd line <3rd line <4th line, each Concentration is different for each line area. That is, the first line is a high concentration region, the second line is a first intermediate region, the third line is a second intermediate region, and the fourth line is a low concentration region. Alternatively, the fourth line is a high concentration region, the third line is a first intermediate region, the second line is a second intermediate region, and the first line is a low concentration region. .

  Although the latent image 2 is divided into 13 in FIG. 2, it is not limited to 13 and can be divided into N (N is an integer of 3 or more). In addition, the 13 areas are assigned to the first line, the second line, the third line, and the fourth line. However, the present invention is not limited to this, and the nth line ( n is an integer of 3 or more.

(Image forming body A1)
The latent image 2 divided into the 13 regions 3 shown in FIG. 2 is divided into the high density region 3a, the first intermediate region 3b1, the second region with respect to each of the 13 regions as shown in FIG. They are distributed to the intermediate region 3b2 and the low concentration region 3c. For each region allocated to the high concentration region 3a, the first intermediate region 3b1, the second intermediate region 3b2, and the low concentration region 3c shown in FIG. Line 4 is applied. FIG. 4 is a diagram showing the image forming body A1. The parallel lines 4 composed of the recessed lines 5 are arranged in different directions for each of the high concentration region 3a, the first intermediate region 3b1, the second intermediate region 3b2, and the low concentration region 3c. Moreover, it can be seen from the XX ′ cross-sectional view shown in FIG. 4 that the line 5 of each recess has a predetermined depth D. In this case, when the arrangement direction of the parallel lines 4a of the high concentration region 3a is 0 °, the arrangement direction of the parallel lines 4b1 of the first intermediate region 3b1 is 30 ° and / or 150 °, and the second intermediate region 3b2 The arrangement direction of the line 4b2 is 60 ° and / or 120 °, and the arrangement direction of the line 4c in the low concentration region 3c is 90 ° and / or 270 °. When the angle in the arrangement direction of the lines in the low concentration region is 0 °, the arrangement of the lines gradually approaches 90 ° and / or 270 ° as the density increases from the low concentration region to the high concentration region. It is necessary to arrange. Moreover, it is preferable that the line | wire width of a recessed part of a line is in the range of 30-500 micrometers, and the pitch width is 70-2000 micrometers.

  FIG. 5 shows the principle when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction. As shown in FIG. 5 (a), the first inclined surface 5a of the line 4a in the high concentration region whose arrangement direction is 0 ° can be confirmed brightly under the influence of the spot light, and the second inclined surface 5b. Can be confirmed dark by the shadow of the spot light. Since the observation direction in this case is the Y2 direction, the first inclined surface 5a cannot be observed, and the second inclined surface 5b can be observed, so that the line 4a can be visually recognized darkly. Therefore, the high density region can be observed in a dark state.

  Next, as shown in FIG. 5B, the first inclined surface 5a of the first line 4b1 of the first intermediate region whose arrangement direction is 30 ° and / or 150 ° is affected by the spot light. The dark area is gradually confirmed by the shadow of the spot light from the bright area, and the second inclined surface 5b can be confirmed dark by the shadow of the spot light. Since the observation direction in this case is the Y2 direction, since the first inclined surface 5a and the second inclined surface 5b of the line 4b1 can be visually recognized, the line 4b1 can be confirmed brighter than the line 4a. Therefore, the first intermediate region can be confirmed brighter than the high concentration region.

  Next, as shown in FIG. 5C, the first inclined surface 5a of the second line 4b2 of the second intermediate region whose arrangement direction is 60 ° and / or 120 ° is affected by the spot light. The second inclined surface 5b is confirmed to gradually become a dark region due to the shadow of the spot light from the bright region due to the influence of the spot light. The Since the observation direction in this case is the Y2 direction, the first inclined surface 5a and the second inclined surface 5b of the line 4b1 can be visually recognized. In addition, since there are fewer shadow areas visible than the line 4b1 shown in FIG. 5B, the line 4b2 can be confirmed to be brighter than the line 4b1. Therefore, the second intermediate region can be confirmed to be brighter than the first intermediate region.

  Next, as shown in FIG. 5 (d), the first inclined surface 5a and the second inclined surface 5b of the line 4c in the low-concentration region whose arrangement direction is 90 ° and / or 270 ° Because it is difficult for shadows to occur, it is visible in a bright state. Since the observation direction in this case is the Y2 direction, the first inclined surface 5a and the second inclined surface 5b of the line 4c can be visually recognized. It is possible to confirm that the line 4c where the shadow is hard to occur is brighter than the line 4b2. Therefore, the low density region can be confirmed brighter than the second intermediate region.

  FIG. 6 shows a principle when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y1 direction which is the same direction as the irradiated light. As shown in FIG. 6A, the first inclined surface 5a of the line 4a in the high concentration region whose arrangement direction is 0 ° can be confirmed brightly under the influence of the spot light, and the second inclined surface 5b. Can be confirmed dark by the shadow of the spot light. Since the observation direction in this case is the Y1 direction, the second inclined surface 5b cannot be observed, and the first inclined surface 5a can be observed, so that the line 4a can be viewed brightly. Therefore, the high density region can be observed in a bright state.

  Next, as shown in FIG. 6B, the first inclined surface 5a of the first line 4b1 in the first intermediate region whose arrangement direction is 30 ° and / or 150 ° is affected by the spot light. The dark area is gradually confirmed by the shadow of the spot light from the bright area, and the second inclined surface 5b can be confirmed dark by the shadow of the spot light. Since the observation direction in this case is the Y1 direction, the first inclined surface 5a and the second inclined surface 5b of the line 4b1 can be visually recognized, so the line 4b1 can be confirmed to be darker than the line 4a. Therefore, it can be confirmed that the first intermediate region is darker than the high concentration region.

  Next, as shown in FIG. 6C, the first inclined surface 5a of the second line 4b2 of the second intermediate region whose arrangement direction is 60 ° and / or 120 ° is affected by the spot light. The second inclined surface 5b is confirmed to gradually become a dark region due to the shadow of the spot light from the bright region due to the influence of the spot light. The Since the observation direction in this case is the Y1 direction, the first inclined surface 5a and the second inclined surface 5b of the line 4b1 can be visually recognized. Further, since there are more shadow areas visible than the line 4b1 shown in FIG. 6B, the line 4b2 can be confirmed to be darker than the line 4b1. Therefore, it can be confirmed that the second intermediate region is darker than the first intermediate region.

  Next, as shown in FIG. 6 (d), the first inclined surface 5a and the second inclined surface 5b of the line 4c in the low-concentration region whose arrangement direction is 90 ° and / or 270 ° However, the amount of reflected light that can be confirmed is small compared to other areas, so that it can be visually recognized in a dark state. Since the observation direction in this case is the Y1 direction, the first inclined surface 5a and the second inclined surface 5b of the line 4c can be visually recognized. The line 4c can be confirmed to be darker than the line 4b2. Therefore, the low density region can be confirmed to be darker than the second intermediate region.

  FIG. 7A shows a view when the image forming body A1 shown in FIG. 4 is observed from the vertical direction. When the image forming body is observed from the vertical direction, the 13 areas 3 forming the latent image 2 are divided into a high density area 3a, a first intermediate area 3b1, a second intermediate area 3b2, and a low density area 3c. The angle of the arrangement direction of the lines is different for each of the high concentration region 3a, the first intermediate region 3b1, the second intermediate region 3b2, and the low concentration region 3c. Since it is 30 to 500 μm, the pitch width is in the range of 70 to 2000 μm, and is formed with a fine line width, the 13 regions 3 are visually recognized in a state that is difficult to distinguish.

  FIG. 7B is a drawing when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction. As shown in FIG. 7B, the high density region can be confirmed to be darkest, followed by the first intermediate region, the second intermediate region, and the low concentration region. Therefore, the latent image 2 has a brightness difference in each of the areas 3 assigned to the high density area 3c, the first intermediate area 3b1, the second intermediate area 3b2, and the low density area 3c. The image image 2 is visually recognized.

  FIG. 7C is a drawing when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y1 direction. As shown in FIG. 7C, the high density region can be confirmed to be brightest, followed by the first intermediate region, the second intermediate region, and the low concentration region. Therefore, the latent image 2 has a brightness difference in each of the areas 3 assigned to the high density area 3c, the first intermediate area 3b1, the second intermediate area 3b2, and the low density area 3c. The image image 2 is visually recognized.

  When the image forming body A1 shown in FIG. 4 is irradiated with spot light from the X1 direction and observed with the naked eye from the X2 direction, the high density area can be confirmed to be brightest, and then the first intermediate area. The second intermediate region and the low concentration region. Furthermore, when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the X1 direction and observed with the naked eye from the X1 direction, the high density region can be confirmed to be the darkest, and then the first intermediate region. The second intermediate region and the low concentration region.

(Image forming body A2)
For each of the regions allocated to the high concentration region 3a, the first intermediate region 3b1, the second intermediate region 3b2, and the low concentration region 3c shown in FIG. 3, a concave line 5 as shown in FIG. 8 is formed. Line 4 is applied. Moreover, it turns out that the line 5 of each recessed part has the predetermined depth D by XX 'sectional drawing shown in FIG. In this case, when each line width of the line 4a in the high concentration region 3a is 50 μm and the pitch width is 100 μm, each line width of the line 4b1 in the first intermediate region 3b1 is 50 μm and the pitch width is 150 μm. Each line width of the 3b2 line 4b2 is 50 μm and the pitch width is 200 μm, and each line width of the line 4c in the low concentration region 3c is 50 μm and the pitch width is 250 μm. That is, in FIG. 8, the pitch width of the lines forming each region is as follows: the pitch width of the lines in the high concentration region <the pitch width of the lines in the first intermediate region <the pitch width of the lines in the second intermediate region. <Each pitch width of the lines in the low concentration region is established. In addition, it is preferable that the line | wire width of a recessed part of a line is in the range of 30-500 micrometers, and the pitch width is 70-2000 micrometers.

  When the image forming body A2 shown in FIG. 8 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction, or when irradiated with spot light from the Y1 direction and observed with the naked eye from the Y1 direction, Since each region has a different pitch width of all lines, the amount of shadow generation is different. Therefore, substantially the same effect as the image forming body A1 can be obtained. In the case where the image forming body A2 shown in FIG. 8 is irradiated with spot light from the X1 direction and observed with the naked eye from the X2 direction, or is irradiated with spot light from the X1 direction and observed with the naked eye from the X1 direction. Thus, the latent image 2 becomes difficult to visually recognize.

(Image forming body A3)
For each of the regions allocated to the high concentration region 3a, the first intermediate region 3b1, the second intermediate region 3b2, and the low concentration region 3c shown in FIG. 3, a concave line 5 as shown in FIG. 9 is formed. Line 4 is applied. Moreover, it can be seen from the XX ′ cross-sectional view shown in FIG. 9 that the line 5 of each recess has a predetermined depth D. In this case, when each line width of the line 4a in the high concentration region 3a is 300 μm, each line width of the line 4b1 in the first intermediate region 3b1 is 200 μm, and each line width of the line 3b2 in the second intermediate region 4b2 The width of each line 3c in the low concentration region 3c is 50 μm. That is, in FIG. 9, the line widths of the lines forming each region are as follows: each line width of the high-concentration region line> each line width of the first intermediate region> each line of the second intermediate region Width> Each line width of the low density region is established. In this case, the pitch of each line width is constant, but each pitch width may be different. In addition, it is preferable that the line | wire width of a recessed part of a line is in the range of 30-500 micrometers, and the pitch width is 70-2000 micrometers.

  When the image forming body A3 shown in FIG. 9 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction, or with spot light from the Y1 direction and observed with the naked eye from the Y1 direction, Since the areas have different line widths, the areas where the shadow can be visually recognized are different depending on the observation angle. Therefore, substantially the same effect as the image forming body A1 can be obtained. In the case where the image forming body A3 shown in FIG. 9 is irradiated with spot light from the X1 direction and observed with the naked eye from the X2 direction, or is irradiated with spot light from the X1 direction and observed with the naked eye from the X1 direction. Thus, the latent image 2 becomes difficult to visually recognize.

  The image forming body A1 represents the low density region to the high density region due to the difference in the arrangement direction of the lines, the image forming body A2 represents the low density region to the high density region due to the difference between the lines, and the image forming body A3 Although the low-concentration region to the high-concentration region are represented by the difference in the line width of the lines, the high-concentration region may be represented from the low-concentration region by combining these. FIG. 10 shows an image forming body A4 formed by combining these.

  The image forming body shown in FIGS. 4, 8, 9 and 10 has the outer shape 6 formed of the concave line 5 in each region, but does not form the outer shape 6 as shown in FIG. May be.

  When the image forming body of the present invention is observed from the vertical direction, each region 3 is visually recognized in a state in which it is difficult to distinguish, so that the line width of the concave portions of each line is 30 to 500 μm and the pitch width is 70 to 2000 μm. It is preferable to produce within the range. When the line width is smaller than 30 μm, it is difficult to produce, and when the line width is larger than 500 μm, it is difficult to obtain the effect of the present invention. The ratio of each line width to each non-line width is preferably about 1: 1 to 1: 3.

  When the image forming body of FIGS. 4, 8, 9 and 10 is observed gradually from the vertical direction to the horizontal direction, the light and dark changes gradually and gradually, so that the latent image has gradation. Visible. Furthermore, the effect of the present invention can be achieved by continuously changing the angle of incident light such as spot light without tilting the image forming body. In addition, the image forming body of the present invention is less likely to cause shadows in a general environment where light is diffused substantially evenly throughout the room, such as indoor lighting, compared to the case where spot light is irradiated. Therefore, the visibility of the latent image having gradation is inferior.

  In the case of forming on a paper substrate, in addition to the latent image 2 described above, an image by transmitted light may be formed as the second latent image. By forming the depth of the image image deeply and forming the depth of the concave line of the second latent image image at a depth that can be confirmed when observed with transmitted light, the second latent image when observed with transmitted light An image can be visually recognized as an image.

  The shape of the line of the present invention can be formed by a straight line pattern, a curved line pattern or the like, and is not particularly limited. Furthermore, although it is preferable to use a solid line for each line, a dotted line and a broken line may be used. Moreover, you may form a solid line, a broken line, a dotted line, etc. by a micro character.

  As the substrate of the present invention, paper sheets, plastic films, metals and the like can be used. In the case of paper sheets, coated paper or art paper having surface gloss is preferable. In the image forming body of the present invention, when the base material is a light-transmitting base material such as a transparent plastic, a latent image appears when the base material is observed by being gradually tilted from the vertical direction to the horizontal direction. The thickness of the base material is not particularly limited, and it is effective from a thin base material of about 60 μm to a card base material of about 760 μm.

  The type of laser of the laser processing means for forming the image forming body of the present invention is not particularly limited, but a carbon dioxide gas laser is preferable. Although there is no particular problem, when the substrate of the present invention is a paper sheet, the edge of the line of the recess may be burned by the heat of the laser. In the case where the substrate of the present invention is a plastic film, a raised portion that protrudes from the surface of the light-transmitting substrate may be formed at the edge of the line of the recess due to the heat of the laser.

(Image forming body manufacturing apparatus)
An image forming body manufacturing apparatus will be described below. As shown in FIG. 12, the image forming body manufacturing apparatus 11 includes an image acquisition unit 12, a line latent image image data generation unit 13, a conversion table storage unit 14, and a laser processing unit 15. The image acquisition unit 12, the line latent image image data generation unit 13, and the conversion table storage unit 14 are performed by a computer or a workstation.

  The image acquisition unit 12 acquires the latent image data 7 that is a set of pixels in which any one of density values 0 to 255 is defined, which is a motif (original image) of the latent image 2 of the image forming body. To do. If it is not latent image data that is an aggregate of pixels in which any one of density values 0 to 255 is defined, image processing is performed on the acquired image. For example, any one of density values 0 to 255 is defined. It is converted into latent image data 7 which is an aggregate of the obtained pixels. An image is acquired by an image scanner, a digital camera, a handy type reader, a camera-equipped mobile phone, or the like.

  The line latent image data generation unit 13 reads the acquired latent image image data 7 from the conversion table 8 stored in the conversion table storage unit 14 in which the density and the arrangement direction of each line are associated with each other. Based on the conversion table 8, the lines are converted into lines having different arrangement directions for each density area of the latent image data 7, and line width and pitch are further defined to generate line latent image data 9.

  An example of the conversion table 8 is shown in FIG. For example, when the density level is divided into 10 levels of 0 to 9, the arrangement direction of the lines is 0 °, 10 °, 20 °, 30 °, 40 °, 50 °, 60 °, 70 °, 80 The angle is 90 °. When converted at 360 °, when the density level is 0, it is 0 °, 180 ° or 360 °, and when the density level is 1, it is 10 °, 170 °, 190 ° or 350 ° and the density level is 2 Is 20 °, 160 °, 200 ° or 340 °, and when the density level is 3, it is 30 °, 150 °, 210 ° or 330 °, and when the density level is 4, it is 40 °, 140 °. When the density level is 5, it becomes 50 °, 130 °, 230 ° or 310 °, and when the density level is 6, it becomes 60 °, 120 °, 240 ° or 300 °. When the density level is 7, it becomes 70 °, 110 °, 250 ° or 290 °, and when the density level is 8, it becomes 80 °, 100 °, 260 ° or 280 °, and when the density level is 9, , 90 ° or 270 °. The density level divides 256 gradations into 0-9. The data in the conversion table 8 is an example, and the present invention is not limited to this.

  The laser processing means 15 forms a latent image composed of concave lines on the surface of the substrate based on the line latent image data. The type of laser of the laser processing means is not particularly limited, but a carbon dioxide laser is preferable.

(Method for producing image forming body)
A method for producing the image forming body will be described below. As shown in FIG. 14, the first step is latent image image data that is a latent image image motif (original image), for example, a collection of pixels in which any one of density values 0 to 255 is defined. 7 is acquired by the image acquisition means.

  If the latent image data 7 is not a latent pixel image data 7 in which any one of density values 0 to 255 is defined, the acquired image is subjected to image processing, and a set of pixels in which any density value 0 to 255 is defined. It is converted into latent image data 7 that is a body. An image is acquired by an image scanner, a digital camera, a handy type reader, a camera-equipped mobile phone, or the like.

  In the second step, the latent image data 7 acquired in the first step is stored in the conversion table storage unit in which the density and the array direction of each line are associated by the line latent image image data generation unit. Based on the converted conversion table 8, the lines are converted into lines having different arrangement directions for each density region of the latent image data 7, and line width and pitch are defined to generate line latent image data 9. .

  In the third step, on the basis of the line latent image image data 9 generated in the second step, a latent image composed of concave lines is formed on the surface of the substrate by laser processing means to obtain an image forming body. The type of laser of the laser processing means is not particularly limited, but a carbon dioxide laser is preferable.

  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.

  The latent image data that is an aggregate of pixels in which any of density values 0 to 255 serving as a motif (original image) of the latent image is defined is acquired by the image acquisition unit. Next, the arrangement direction of the latent image data is determined for each density area of the latent image data based on a conversion table in which the density and the arrangement direction of each line are associated by the line latent image data generation unit. Converted to different lines, and further defined the line width of the concave portions of 100 μm and the pitch width of 200 μm to generate line latent image data.

  The line latent image image data is obtained by dividing the latent image into 20 areas for each part and density, and further dividing the divided 20 areas into a low density area, a first intermediate area, and a second intermediate area. The third intermediate region and the high concentration region are divided into five stages, and when the arrangement direction of the lines of the high concentration region is set to 0 °, the first intermediate region is 25 ° and the second intermediate region is 50 °. The third intermediate region was 75 °, and the low concentration region 4 was 90 °.

  Based on the line latent image data, a laser processing machine formed a latent image composed of concave lines at a depth of 50 μm on the surface of the substrate 1 to obtain an image forming body B1. FIG. 15 shows the image forming body B1. The latent image 2 of the image forming body B1 is composed of 20 areas 3, each of which is a high density area 3a where the arrangement direction of the lines is 0 °, and the first direction where the arrangement direction of the lines is 25 °. The intermediate region 3b1, the second intermediate region 3b2 in which the arrangement direction of the line is 50 °, the third intermediate region 3b3 in which the arrangement direction of the line is 75 °, and the low concentration in which the arrangement direction of the line is 90 ° Any one of the five stages of the region 3c is selected and formed. The recess has a line width of 100 μm, a pitch width of 200 μm, and a depth of 50 μm.

  As shown in FIG. 16A, when the image forming body B1 of Example 1 is observed from the vertical direction, the 20 areas 3 forming the latent image 2 are a low density area, a first intermediate area, 2 intermediate regions, third intermediate regions, fourth intermediate regions, and high concentration regions, low concentration regions, first intermediate regions, second intermediate regions, third intermediate regions, fourth intermediate regions The angle in the arrangement direction of the lines is different for each region and the high-concentration region, but the line width of the recesses of the lines is 100 μm, the pitch width is in the range of 200 μm, and the line is formed with a fine line width. Therefore, the 20 areas are difficult to distinguish.

  FIG. 16B is a drawing when the image forming body B1 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction. As shown in FIG. 16B, the high density region can be confirmed to be the darkest, followed by the first intermediate region, the second intermediate region, the third intermediate region, the fourth intermediate region, and the low concentration region. The brightness difference occurred in each region 3, and the latent image 2 was visually recognized with gradation.

  FIG. 16C is a drawing when the image forming body B1 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y1 direction. As shown in FIG. 16C, the high density region can be confirmed brightest, and subsequently becomes the first intermediate region, the second intermediate region, the third intermediate region, the fourth intermediate region, and the low concentration region. The brightness difference occurred in each region 3, and the latent image 2 was visually recognized with gradation.

  Although the present invention has been described based on the embodiment of the present invention, the present invention is not limited to this embodiment, and various other implementations are possible within the scope of the technical idea described in the claims. Possible forms.

It is explanatory drawing of the line 5 of the recessed part which has the predetermined width W formed in the image forming body of this invention. FIG. 6 is a diagram in which the image is divided into 13 regions 3 for each part forming the latent image 2 serving as a motif (original image) and / or for each lightness of the color forming the latent image 2. FIG. 13 is a diagram in which each of the 13 regions is divided into a high concentration region 3a, a first intermediate region 3b1, a second intermediate region 3b2, and a low concentration region 3c. It is a figure which shows image forming body A1. FIG. 5 is a diagram illustrating the principle when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y2 direction. FIG. 5 is a diagram showing the principle when the image forming body A1 shown in FIG. 4 is irradiated with spot light from the Y1 direction and observed with the naked eye from the Y1 direction. FIG. 5 is a diagram illustrating a case where the image forming body A1 illustrated in FIG. 4 is observed in a predetermined state. It is a figure which shows image forming body A2. It is a figure which shows image forming body A3. It is a figure which shows image forming body A4. The outer shape 6 is a diagram showing an example in which the outer shape 6 is not formed by a line of a recess. It is a figure which shows the production apparatus 11 of an image forming body. It is a figure which shows the conversion table. It is a flowchart which shows the preparation methods of an image forming body. It is a figure which shows image forming body B1. It is a figure which shows the case where it observes with respect to image forming body B1 in a predetermined state.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Latent image 3 Area 3a High density area 3b1 First intermediate area 3b2 Second intermediate area 3c Low density area 4, 4a, 4b1, 4b2, 4c Line 5 Recess line 5a First inclined surface 5b Second inclined surface 6 Outline shape 7 Latent image data 8 Conversion table 90,000 line latent image data 11 Production apparatus 12 Image acquisition means 130,000 line latent image image data generation means 14 Conversion table storage means 15 Laser processing means A1 , A2, A3, A4, B1 Image forming body D Predetermined depth W Predetermined width

Claims (3)

In the image forming body in which the latent image is formed by the line of the concave portion on the base material, and the latent image having a gradation can be confirmed when the base material is tilted and observed,
The latent image is divided into N areas (N is 3 or more),
Each of the N regions is divided into a first line, a second line,..., An nth line (n is 3 or more).
The first line, the second line,..., The n-th line are different from each other in the arrangement direction of the lines, the difference in line width of the lines, the line An image forming body comprising a difference in pitch width or a combination thereof. 2. The image forming body according to claim 1, wherein the line width of the recesses of the line is 30 to 500 [mu] m and the pitch width is in the range of 70 to 2000 [mu] m. In a method for producing an image forming body in which a latent image is formed by a line of a concave portion on a base material, and when the base material is tilted and observed, a latent image having a gradation can be confirmed.
Obtaining latent image data which is an aggregate of pixels in which density values defined as an original image of the latent image are defined;
The acquired latent image data is converted into a line having a different arrangement direction for each density area of the latent image data based on a conversion table in which the density and the arrangement direction of each line are associated with each other. Furthermore, a step of defining line width and pitch and generating line latent image data,
A method for producing an image forming body comprising a step of forming a latent image on the surface of the base material by means of concave lines based on the line latent image data.

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