JP7445203B2 - Reflector with latent image - Google Patents

Description

The present invention relates to a reflector having a latent image, and more particularly to a reflector that can make a latent image embedded in the reflective surface visible and recognizable by changing the reflection angle of the reflective surface of the reflector.

Latent images are sometimes embedded in the reflective surfaces of gift certificates, admission tickets, stock certificates, etc. for the purpose of preventing forgery, illegal copying, decoration, etc. The latent image embedded in the reflective surface can be made visible and recognized by the viewer by changing the reflection angle of the reflective surface. For example, Japanese Patent Laid-Open No. 2019-84719 discloses a shaped card that is an example of this type of reflector.

JP2019-84719

There is only one type of latent image embedded in the reflective surface of the conventional shaped card. Therefore, no matter what reflection angle the shaped card is at, the observer can only recognize one type of latent image.
An object of the present invention is to embed multiple types of latent images that overlap at least in part, and to make each of the multiple types of latent images visible and recognized according to the reflection angle by changing the reflection angle. The object of the present invention is to provide a reflector having a reflective surface capable of reflecting.

In order to solve the above problems, a reflector according to one aspect of the present invention includes a first area defined by a first parallel line and a second area defined by a second parallel line, which is formed at a different angle from the first parallel line. a background area overlapping a second area defined by the parallel lines, and an angle that intersects both the first parallel lines and the second parallel lines, and between the first parallel lines; a third parallel line that makes visible the first latent image formed in the background area of the reflective surface, with the intersection angle set to be larger than the intersection angle between the second parallel line and the second parallel line; At an angle that intersects all of the first to third parallel lines, and with the intersection angle with the second parallel lines set larger than the intersection angle with the first parallel lines, It is characterized by having a reflective surface that includes at least a fourth parallel line that makes visible the second latent image formed in the background area of the reflective surface.
The reflector may be a printed matter.
According to the reflector of this aspect, it is possible to embed multiple types of latent images that overlap at least in part on the reflective surface, and by changing the reflection angle of the reflective surface, multiple types of latent images can be embedded according to the reflection angle. Each of the latent images can be made visible and recognized by the viewer.

In the reflector of the above aspect, each of the first to fourth lines may include concave lines and convex lines that are alternately arranged next to each other.
Such an arrangement is particularly useful when using printing technology.

Furthermore, in the reflector of the above aspect, the surface of the convex line may be covered with printing varnish, and the surface of the concave line may be formed of a material that repels the varnish. Preferably, the printing varnish is a flexo varnish.

Further, in the reflector of the above embodiment, it is preferable that the dimension between the surface of the convex line and the surface of the concave line is 1 to 8 μm or less.

Further, in the reflector of the above aspect, it is preferable that each width of the first convex line is 0.2 to 0.35 μm.
In the reflector of the above embodiment, it is preferable that the distance between the convex lines is 0.05 to 0.1 μm.

In the reflector of the above aspect, the intersection angle between the first parallel line and the third parallel line, and the intersection angle between the second parallel line and the fourth parallel line, Preferably, each line is about 90 degrees, and the angle of intersection between the first parallel line and the second parallel line is preferably about 45 degrees.
By setting at such an angle, the latent image can be made more clearly visible by utilizing the brightness difference.

According to the present invention, it is possible to embed a plurality of types of latent images that overlap at least in part, and by changing the reflection angle, each of the plurality of types of latent images can be made visible and recognized according to the reflection angle. Provided is a reflector having a reflective surface capable of reflecting.

An example in which a reflector according to an embodiment of the present invention is used in a card is shown. An example in which a reflector according to an embodiment of the present invention is used for banknotes is shown. 3 is a conceptual diagram showing a state in which the reflection angle of a reflection surface of a reflector according to an embodiment of the present invention is changed. 3 is a conceptual diagram showing a state in which the reflection angle of a reflection surface of a reflector according to an embodiment of the present invention is changed. 3 is a conceptual diagram showing a state in which the reflection angle of a reflection surface of a reflector according to an embodiment of the present invention is changed. 5 is a partially enlarged view of portion "IV" in FIG. 4. FIG. 6 is a partially enlarged view of portion “V” in FIG. 5. FIG. FIG. 2 is a schematic diagram of a cross section of a printed matter. FIG. 2 is a diagram plotting the evaluation results of Examples and Comparative Examples.

Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative positions of components, etc. described in the following embodiments are arbitrary and can be changed depending on the configuration of the device to which the present invention is applied or various conditions. Further, unless otherwise specified, the scope of the present invention is not limited to the embodiments specifically described below.

1 and 2 illustrate how a reflector according to an embodiment of the present invention is used. FIG. 1 shows an embodiment in which the reflector is used for a card, and FIG. 2 shows an embodiment in which the reflector is used in a banknote. 1A and 1B show the same card 3, but show a state in which the reflection angle of the reflection surface 1a of the reflector 1 provided on the card 3 has been changed. As is clear from comparing FIGS. 1A and 1B, changing the reflection angle changes the scenery seen by the observer. More specifically, at the reflection angle in FIG. 1(a), for example, the letter "S" can be observed on the reflective surface 1a of the reflector 1, whereas at the reflection angle in FIG. For example, the character "U" can be observed on the reflective surface 1a of the reflector 1. Although not particularly illustrated, by similarly changing the reflection angle of the banknote 4 shown in FIG. , "D", and other letters. Of course, the modes of use shown in FIGS. 1 and 2 are not intended to limit the reflector 1 of the present invention to cards and banknotes, and the reflector 1 of the present invention can be used for various purposes other than cards, etc. Can be used for goods. Furthermore, the reflector 1 itself can be an article itself.

3 to 5 each conceptually show the reflective surface 1a of the reflector 1 shown in FIG. 1 in more detail. These figures all show the same reflective surface 1a of the same reflector 1, but similarly to FIGS. 1(a) and (b), each figure shows the reflection angle of the reflective surface 1a changed. Sometimes it is a separate representation of a state as it appears to different observers. More specifically, the latent images are made visible by changing the reflection angle of the reflective surfaces 1a of a plurality of types, in this case two types, of latent images that overlap at least in part. These states are shown in separate drawings. Incidentally, it is sufficient that the reflective surface 1a can reflect light, but it is preferable that the reflective surface 1a has gloss.

As an example of a reflector, a printed matter 1 manufactured using printing technology is illustrated here. Of course, there is no intention to limit the present invention to the printed matter 1. Any reflector other than printed matter 1 may be used as long as the principles of the present invention can be applied, for example, it may be manufactured using conventional embossing. Alternatively, it may be used by being attached to the surface of a product.

For example, when an observer observes the reflective surface 1a from the front without tilting the printed matter 1, both the first latent image A and the second latent image B become apparent, as shown in FIG. It is assumed that an image in which both the first latent image A and the second latent image B are mixed is observed on the reflective surface 1a. In this case, it is difficult to clearly recognize the first latent image A and the second latent image B, especially in their overlapping portion "C". Can not.

On the other hand, when the printed matter 1 is tilted at the first angle "Θ1" and the reflective surface 1a is observed, the observer sees the first latent image A as shown in FIG. 1(a) and FIG. For example, only the character "S" can be made visible and recognized in a state distinguished from the second latent image B, for example, the character "U". Note that at this time, the observer cannot substantially recognize the second latent image B, which is the character "U".

Furthermore, when the printed matter 1 is tilted at the second angle "Θ2" and the reflective surface 1a is observed, the observer sees a second latent image B as shown in FIG. 1(b) and FIG. Only a certain character "U" can be made visible and recognized separately from the character "S" which is the first latent image A. Note that at this time, the observer cannot substantially recognize the letter "S" which is the first latent image A.

In this way, when the observer changes the reflection angle of the reflective surface 1a of the printed matter 1 and observes it, the observer can see that each of the first latent image A and the second latent image B is at least partially Even when there is overlap, it is possible to make them manifest and recognize them in a state where they are clearly distinguished from each other. Note that although the letters "S" and "U" are shown as examples of latent images, this is merely an example, and of course any latent image can be used as long as the principles of the present invention can be applied. It's okay.

Next, the structure of the reflective surface 1a will be explained in more detail with reference to FIGS. 6 to 8. 6 is a partial enlarged view of portion "IV" in FIG. 4, FIG. 7 is a partial enlarged view of portion "V" of FIG. 5, and FIG. 8 is a schematic cross-sectional view of printed matter 1. This is what is shown.

The reflective surface 1a is provided with a plurality of sets, in this case four sets (parallel lines 10, 20, 30, and 40), of a plurality of sets of parallel lines each forming an individual parallel line. In order to facilitate adjustment of the reflected light, it is preferable that the plurality of parallel lines have a uniform width and are arranged at uniform intervals. In this embodiment, all of these lines 10 to 40 are formed using a known printing technique. By using printing technology, reflectors can be manufactured faster and at lower cost than by embossing, and more delicate lines can be formed on the reflective surface. The plurality of parallel lines constituting the parallel lines are concave lines (concave lines 10-1 to 40-1 in FIGS. 6 to 8, which will be described later) that are uneven in cross-section and are alternately arranged next to each other. Convex lines (convex lines 10-2 to 40-2 in FIGS. 6 to 8, which will be described later) are included. Note that the concave line 20-1 in FIG. 6 and the concave line 10-1 in FIG. It can be assumed that it has been formed. In addition, in FIGS. 6 and 7, the concave lines are shown thicker than the convex lines, but this is for convenience and as will be explained later with reference to FIG. , the width of these concave lines and the width of the convex lines may be substantially the same. Furthermore, in this embodiment, it is sufficient that each set of lines 10, 20, 30, and 40 includes a concave line and a convex line. For example, as shown in this embodiment, when printing technology is used, printing ink generally forms convex lines, but when this is transferred, the convex lines are This is because a concave line will be formed, and conversely, a concave line will form a convex line. Therefore, in the final product form, the printing ink does not necessarily form a convex line on the reflective surface.

The first line 10 is mainly for making the first latent image A visible, and defines a first area "α" on the reflective surface 1a. On the other hand, the second parallel lines 20 formed at a different angle from the first parallel lines 10 are mainly for making the second latent image B visible. Define a region "β".

The portion "γ" where the first region "α" and the second region "β" overlap functions as a background region in which both the first latent image A and the second latent image B can be embedded. . It is sufficient to form the background region "γ" only in the region where both the first latent image A and the second latent image B need to be embedded. The embodiments shown in FIGS. 3 to 5 are based on the premise that the first latent image and the second latent image can be embedded in any area. Both of the second regions "β" are provided over the entire reflective surface 1a, and as a result, the first region "α", the second region "β", and the background region "γ" , all occupy the same area. However, it is not necessarily necessary to provide the second area "β" in the area where only the first latent image A is embedded, and similarly, the area where only the second latent image B is embedded does not necessarily have the second area "β". There is no need to provide "α". Therefore, the first area "α" or the second area "β" and the background area "γ" do not always need to occupy the same area, as shown in FIGS. 3 to 5.

The first parallel lines 10 and the second parallel lines 20 are provided at different angles from each other in the background region "γ". As a result, these first parallel lines 10 and second parallel lines 20 intersect with each other. Although the intersection angle "θ1" between the first parallel lines 10 and the second parallel lines 20 is not limited, it is preferably set to about 45 degrees as in the illustrated embodiment. By setting at such an angle, the design of the reflector 1 can be facilitated. Note that the term "intersection angle" in this specification refers to an acute angle at which two lines intersect, in other words, the smaller of two angles formed by two lines.

In order to embed multiple types of latent images, a plurality of parallel lines, here the third parallel line 30 shown in FIG. 6 and the fourth parallel line 40 shown in FIG. 7, are provided in the background area "γ". ing. At least two latent images and parallel lines corresponding to each latent image are sufficient to be embedded in the background region "γ", but two or more may be provided.

The first latent image A is embedded by the third parallel line 30 shown in detail in FIG. The third parallel line 30 is provided at an angle that intersects both the first parallel line 10 and the second parallel line 20. Further, the third parallel lines 30 are provided with the intersecting angle "θ2" with the first parallel lines 10 set to be larger than the intersecting angle "θ3" with the second parallel lines 20. ing. In order to show the angular relationship between the third parallel line 30 and the fourth parallel line 40, for convenience, FIG. It shows.

The second latent image B is embedded by the fourth line 40 shown in detail in FIG. The fourth parallel line 40 is provided at an angle that intersects all of the first to third parallel lines 10 to 30. Further, the fourth parallel lines 40 are provided with the intersecting angle "θ4" with the second parallel lines 20 set to be larger than the intersecting angle "θ5" with the second parallel lines 20. ing. In order to show the angular relationship between the fourth parallel line 40 and the third parallel line 30, for convenience, FIG. It shows.

FIG. 8 schematically shows a cross section of the printed matter 1, particularly a cross section in a direction intersecting a plurality of parallel lines constituting each parallel line. This diagram can be understood to be common to all lines 10 to 40. As is clear from this figure, the printed matter 1 mainly includes a base material 5 and two types of layers 51 and 52 arranged on the surface of the base material 5 in its cross-sectional direction.

The material of the base material 5 is not particularly limited as long as it is a printable medium. Various materials can also be used, such as paper, plastic, thin metal foil, film, etc.

The layer 51 corresponds particularly to the concave lines 10-1, 20-1, 30-1, and 40-1 (see also FIGS. 6, 7, etc.) among the plurality of parallel lines constituting each line. , On the other hand, the layer 52 is made of convex lines 10-2, 20-2, 30-2, and 40-2 (see also FIGS. 6, 7, etc.) among a plurality of parallel lines constituting each line. ). The reflective surface 1a includes both a surface 51a of the concave lines 10-1 to 40-1 forming the layer 51 and a surface 52a of the convex lines 10-2 to 40-2 forming the layer 52.

Layer 51 can be formed using underprint ink. Therefore, the surface 51a of the layer 51 is covered with the underprint ink.

On the other hand, layer 52 can be formed using topcoat ink. The overcoat ink is applied to both the base material 5 and the underprint ink layer 51 previously applied to the base material 5. In this way, the topcoat ink is applied to both the base material 5 and the underprint ink layer 51, but since it is repelled by the underprint ink, the overcoat ink is applied onto the underprint ink layer 51 in the final product. In addition, a layer 52 of topcoat ink is not formed. As is clear, in the final product, the surface 52a of the layer 52, in other words, the surfaces 52a of the convex lines 10-2 to 40-2 constituting the layer 52 are formed using topcoat ink, The surfaces 51a of the concave lines 10-1 to 40-1 constituting the layer 51 may be formed using underprint ink.

As the top coating ink for forming the layer 52, for example, a printing varnish such as flexo varnish can be used. By using flexo varnish, the height of the layer 52, more specifically, the difference between the surface 52a of the convex lines 10-2 to 40-2 and the surface 51a of the concave lines 10-1 to 40-1 It becomes easier to maintain the dimension "m", and therefore, it is easier to obtain a sense of the depth of lines 10 to 40 on the reflective surface 1a. The dimension "m" is preferably 1 to 8 μm, more preferably from 1 to 8 μm, considering the line width ("line width n" in FIG. 8), separation distance ("separation distance k" in FIG. 8), brightness difference, etc., which will be described later. It is 2 to 7 μm. By using flexo varnish, such dimensions can be easily achieved.Furthermore, since flexo varnish has excellent gloss, the reflectance of the surface 52a of the convex lines 10-2 to 40-2 is set to be particularly high. can do.

As the underprinting ink for forming the layer 51, for example, a known material mixed with a polymer, a monomer, and a photopolymerization initiator can be used. Since the underprint ink needs to repel the topcoat ink, it is preferable that it contains a liquid repellent. By containing a liquid repellent, even when the topcoat ink is applied to both the base material 5 and the layer 51, the varnish of the topcoat ink can be easily repelled in the layer 51, and the layer 51 can be exposed. Can be done.

An example of a method for manufacturing the printed matter 1 will be described mainly with reference to FIG. First, a pattern is printed on the surface of the sheet-like base material 5 with, for example, an ultraviolet curable underprinting ink containing a liquid repellent, and the ink is cured by ultraviolet rays. This pattern printing is preferably performed by an offset printing method or a flexographic printing method, and an offset printing method is more preferred. Pattern printing is performed in the form of parallel lines, and on top of the layer of underprint ink formed by the parallel lines, for example, an ultraviolet curable topcoat ink is further applied. The topcoat ink is applied not only on the base material 5 but also on the underprint ink layer, but as mentioned above, since the underprint ink contains a liquid repellent, On the ink layer, the topcoat ink is repelled, and as a result, a layer of topcoat ink formed by parallel lines is formed between layers of underprint ink formed by parallel lines. In other words, as shown in FIG. 6, FIG. , convex portions 10-2 to 40-2 made of topcoating ink are formed in a parallel line shape. After being in this state, the top coating ink is cured by ultraviolet rays. Although optional, it is preferable to further apply, for example, an ultraviolet curable coating agent to both the topcoat ink layer and the underprint ink layer to form a surface layer (not shown). Note that although the uneven portions may be formed directly with ink in this way, these portions may also be formed using transfer, as disclosed in JP-A No. 2019-84719 and the like.

Next, the principle of operation of the reflective surface 1a will be explained.
Since the first to fourth parallel lines 10 to 40 are each formed in a concave and convex shape, the light incident on the reflective surface 1a is transmitted to the concave lines 10-1 to 40-1 of each of the parallel lines 10 to 40. Then, part of the light is absorbed and reflected from the reflective surface 1a with reduced brightness. Since these first to fourth parallel lines 10 to 40 are provided at mutually different intersecting angles, the amount of reduction in the brightness of the incident light due to the parallel lines formed at a certain angle and the amount of decrease in the brightness of the incident light due to the parallel lines formed at a certain angle, The difference between the amount of reduction in the brightness of the incident light caused by the parallel lines (hereinafter referred to as "brightness difference" for convenience) becomes larger as the intersection angle between the lines becomes larger, and becomes smaller. The more you go, the smaller it becomes. As a result, when there are multiple parallel lines that intersect with a certain predetermined parallel line, by appropriately adjusting the intersecting angle between them, when observing the reflective surface 1a at a certain angle, the predetermined parallel line can be observed. By setting the brightness difference between a line and any of the lines that intersect with it to be larger than the brightness difference between other lines, it is possible to recognize only the lines that have a relationship with the predetermined line. It is possible to set the brightness difference to such a degree that the other lines cannot be recognized as boundary lines. This configuration utilizes this brightness difference to make only predetermined parallel lines visible and recognizable according to the angle of the reflective surface, and is capable of representing at least two latent images. .

More specifically, as clearly shown in FIG. 6, in this configuration, the third parallel line 30 intersects both the first parallel line 10 and the second parallel line 20. , the intersection angle "θ2" with the first parallel lines 10 is set larger than the intersection angle "θ3" with the second parallel lines 20. Therefore, for example, the reflective surface 1a is When observed at an angle Θ1, the difference in brightness between the first parallel line 10 and the third parallel line 30 is larger than the difference in brightness between the second parallel line 20 and the third parallel line 30. As a result, although it is difficult to recognize the third parallel line 30 formed in the background area "γ" in relation to the second parallel line 20, the first parallel line 10 is It can be easily recognized in relation to this, and therefore, it is possible to make the first latent image A represented by the third parallel lines 30 visible.

On the other hand, as well shown in FIG. 7, the fourth line 40 that intersects with the third line 30 is similar to the third line 30, and the fourth line 40 intersects with the first line 10 and the second line 20. , the intersection angle "θ4" with the second parallel line 20 is set larger than the intersection angle "θ5" with the first parallel line 10. Therefore, for example, when the reflective surface 1a is observed at a second angle "Θ2" different from the first angle "Θ1", the luminance between the second parallel lines 20 and the fourth parallel lines 40 The difference becomes larger than the difference in brightness between the first parallel lines 10 and the fourth parallel lines 40, and as a result, the fourth parallel lines 40 formed in the background area "γ" are compared to the first parallel lines 40. Although it is difficult to recognize in relation to the line 10, it can be easily recognized in relation to the second parallel line 20, and therefore, the second parallel line represented by the fourth parallel line 40 It becomes possible to make the latent image B of .

In this way, even if the reflective surface 1a is the same, when observed at the first angle "Θ1", the third parallel line 30 is divided into the background region "γ" and the first region "α". On the other hand, when observed at the second angle "Θ2", the fourth parallel line 40 can be recognized in the background region "γ", especially in the second region "β". ”, and can be provided through these actions, namely, the first latent image “A” manifested by the third parallel line 30; A reflector 1 is provided that has a reflective surface 1a that includes a second latent image "B" made visible by the fourth line 40.

As is clear from the above description, the intersection angle "θ2" between the first parallel line 10 and the third parallel line 30 and the intersection angle "θ2" between the second parallel line 20 and the fourth parallel line 40 It is preferable that the intersection angle "θ4" between the first parallel lines 10 and the second parallel lines 20 is about 90 degrees, and the intersection angle "θ1" between the first parallel lines 10 and the second parallel lines 20 is about 45 degrees. is preferred. This is because it is generally thought that the luminance difference will be the largest when set at such an angle. However, these intersection angles can be freely adjusted within a range that can produce a brightness difference according to the principle of the present invention explained above. For example, for "θ2" and "θ4", if each is within the range of at least 90 degrees ± 10 degrees, and for "θ1", if it is within the range of at least 45 degrees ± 10 degrees, it is sufficient for practical use. can withstand. Therefore, the above-mentioned "about 90 degrees" and "about 45 degrees" include at least these ranges.

Examples and comparative examples will be explained.
[Example 1]
In the printed matter 1 of Example 1, a biaxially stretched polyester film with a thickness of 188 μm was used as the base material 5. A color was applied to the base material 5 using an offset sheet-fed printing machine equipped with an ultraviolet irradiation device. The colors include various colors of KCMY. Next, UV HJK underprint varnish (T&K TOKA Co., Ltd.) as an underprint ink was applied to the colored base only in the areas forming concave lines 10-1 to 40-1, each having a width of 0.075 μm. (corresponding to "separation distance k" in FIG. 8), and the concave lines 10-1 to 40-1 are spaced from each other by 0.225 μm (corresponding to "line width n" in FIG. 8). (corresponding) were applied in a uniformly spaced manner. This underprint ink contains a liquid repellent. Finally, UV Coat Varnish HTA-W (T&K TOKA Co., Ltd.), which is a flexo varnish as a topcoat ink, was applied to the entire base including the area to which the underprint ink was applied. At this time, the convex lines 10-2 to 40-2 are repelled by the concave lines 10-1 to 40-1, and finally the convex lines 10-2 to 40-2 are repelled by the concave lines 10-1 to 40-1. The lines 10-1 to 40-1 remained only in the areas spaced apart from each other. As is clear, the width of each of the convex lines 10-2 to 40-2 is 0.225 μm, which is the same as the distance between the concave lines 10-1 to 40-1. corresponding). In particular, the amount of topcoat ink to be applied is determined between the surface 52a of convex lines 10-2 to 40-2, which is the surface of topcoat ink, and the surface 52a of concave lines 10-1 to 40, which is the surface of underprint ink. -1 and the surface 51a was adjusted so that the dimension "m" was 7 μm. After the treatment in each device, the ink and the like were cured by ultraviolet rays using an ultraviolet irradiation device connected to each device.

In Examples 2 to 4 and Comparative Examples 1 to 4, printed matter was manufactured by changing only the sizes of "line width n" and "separation distance k" in FIG. 8 and keeping other conditions the same.

For each of these Examples and Comparative Examples, quality evaluation was performed regarding "roughness of lines" and "remaining varnish". The evaluation results are shown in Table 1 below. FIG. 9 is a diagram in which the evaluation results are plotted with "line width n" and "separation distance k" set as the horizontal and vertical axes, respectively.

[Table 1]

In Table 1 and FIG. 9, "line width n" corresponds to each width of the convex lines 10-2 to 40-2, in other words, the width "n (μm)" of the convex portion 52 shown in FIG. On the other hand, "distance k" corresponds to each width of concave lines 10-1 to 40-1, in other words, the distance "k (μm)" between convex lines 10-2 to 40-2. do.

"Roughness of parallel lines" is an evaluation of whether the parallel lines forming the parallel lines are clearly visible. Thirty evaluators visually evaluated the roughness of the lines under the same environment with their eyes separated from the reflective surface 1a by about 30 cm. Each evaluator evaluated the roughness as either "〇 (good)" or "× (coarse)", and the one with the larger number of evaluations was adopted as the evaluation result.

"Remaining varnish" is an evaluation regarding whether or not the topcoat ink layer 52, that is, the flexographic varnish, remains on the surface (bottom surface of the parallel lines) 51a of the underprint ink layer 51. As described above, the layer 52 was also applied to the underprint ink layer 51, and whether or not this was sufficiently repelled was visually evaluated. Visual inspection was performed under the same conditions and method as for "line roughness." Each evaluator evaluated the degree of varnish remaining as either "absent (not remaining)" or "presence (remaining)", and the one with the larger number of evaluations was adopted as the evaluation result.

The "overall evaluation" is given by the same evaluator as "〇 (good)" based on the evaluation results of "line roughness" and "remaining varnish" and whether or not it can withstand practical use. , ``△ (fair)'', or ``× (bad)'', and the one with the highest number of evaluations was adopted as the evaluation result. In FIG. 9, these displays are used as each plot.

As inferred from FIG. 9, the "line width n" is preferably 0.2 to 0.35 μm when the line width is uniform, and the "spacing distance k" is preferably 0.2 to 0.35 μm when the line width is uniform. It has become clear that in the case of 0.05 to 0.1 μm is preferable. In addition, the "comprehensive evaluation" revealed that varnish residue has a significant impact on practical use.

Note that the present invention is not limited to the embodiments described above, and various other changes are possible.
For example, lines do not necessarily need to be formed using unevenness as long as a brightness difference can be generated according to the principles of the present invention. For example, instead of creating an uneven pattern, the chromaticity or the like between the parallel lines may be changed to produce brightness.

Further, in the above-described embodiment, a reflector having a reflective surface including two latent images is exemplified, but a reflector having a reflective surface including three or more latent images may also be used. More specifically, in addition to the first and second areas, a third area, etc., in which a fifth line similar to the first to fourth lines extends, is provided to correspond to the third area, etc. Then, a sixth parallel line or the like is provided that intersects with this, so that the reflector has a reflective surface containing three or more latent images including the third latent image represented by the sixth parallel line. You can also do that.

Further aspects, features and advantages of the present invention will become apparent from the following detailed description, which merely sets forth a number of specific embodiments and examples, including the best mode contemplated for carrying out the invention. It will become clear. The invention may also be constructed in other and different embodiments, and its numerous details may be changed in various obvious respects without departing from the spirit and scope of the invention. Accordingly, the drawings and description are to be regarded as illustrative only, and not as restrictive.

1 Reflector 1a Reflective surface 10 First lines 20 Second lines 30 Third lines 40 Fourth lines 51 Underprint ink layer 51a Concave line surface 52 Overcoat ink layer ( flexo varnish for printing)
52a Convex line surface A First latent image B Second latent image α First area β Second area γ Background area

Claims (11)

a background area where a first area defined by the first parallel lines and a second area defined by the second parallel lines formed at a different angle from the first parallel lines overlap;
An angle that intersects both the first parallel line and the second parallel line, and the intersection angle between the first parallel line and the second parallel line is greater than the intersection angle between the second parallel line. a third parallel line that makes the first latent image formed in the background area visible in the set state;
At an angle that intersects all of the first to third parallel lines, and with the intersection angle with the second parallel lines set to be larger than the intersection angle with the first parallel lines. , a fourth parallel line that makes the second latent image formed in the background area visible;
A reflector characterized by having a reflective surface that includes at least. 2. The reflector according to claim 1, wherein each of the first to fourth lines includes concave lines and convex lines that are alternately arranged next to each other. 3. A reflector according to claim 2, wherein the surface of the convex line is covered with a printing varnish. 4. A reflector according to claim 3, wherein the surface of the concave lines is formed of a material that repels the varnish. The reflector according to claim 3 or 4, wherein the printing varnish is flexo varnish. The reflector according to any one of claims 2 to 5, wherein the dimension between the surface of the convex line and the surface of the concave line is 1 to 8 μm. The reflector according to any one of claims 2 to 6, wherein each of the convex lines has a uniform width of 0.2 to 0.35 μm. The reflector according to any one of claims 2 to 7, wherein the distance between the convex lines is uniform and ranges from 0.05 to 0.1 μm. The intersection angle between the first parallel line and the third parallel line and the intersection angle between the second parallel line and the fourth parallel line are each about 90 degrees. A reflector according to any one of claims 1 to 8. 10. The reflector according to claim 1, wherein the angle of intersection between the first parallel line and the second parallel line is approximately 45 degrees. The reflector according to any one of claims 1 to 10, which is a printed matter.

Images