JP3061201B2 - Relief hologram having repeated pattern and emboss duplication method thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a relief hologram having a repetitive pattern and a method for continuously emboss-replicating the repetitive pattern from a mold having a limited size.

[0002]

2. Description of the Related Art A hologram generally records an interference pattern of light, and is used in various fields as a high-density information recording medium, including recording and displaying of a two-dimensional image and a three-dimensional image. Among these, the relief hologram is obtained by recording the interference fringes of the hologram in a photoresist or the like as a concavo-convex pattern, and then molds the concavo-convex pattern by plating or the like, and molds the mold with a transparent thermoplastic resin or the like or a surface of such resin. By embossing a material on which a reflective layer made of metal or the like is formed, a large number of copies are made. The relief hologram is provided with a transmission type relief hologram formed by simply embossing the relief surface on the surface of a transparent resin film and a reflective layer such as a metal layer and a high refractive index layer on the relief surface. There is a reflection-type relief hologram that reproduces an image by reflected and diffracted light. The reflective relief hologram includes a case in which incident light is almost completely reflected by a reflective layer and a case in which a hologram reproduced image is superimposed on a background which reflects a part of incident light and transmits the incident light. In the present application, both of these will be referred to as a reflective relief hologram. In addition, there may be a case where the concavo-convex pattern is simply a pattern in which phase diffraction grating patterns are appropriately arranged, but this is also included in the relief hologram.

[0003] The transmission type relief hologram and the reflection type relief hologram typically have a cross-sectional structure as shown in FIGS. 8 (a) and 8 (b). (Relief surface) is composed of a single layer of a hologram layer 1 made of a thermoplastic resin or the like formed on the surface, and a reflection type relief hologram is composed of such a hologram layer 1 and a reflection layer 2 formed on the relief surface. The reflective layer 2 may be formed of a metal film deposited of aluminum, tin, or the like, or may be formed of a transparent film of high refractive index such as zinc sulfide. When formed of a vapor-deposited metal film, it becomes a reflection-type relief hologram that reflects incident light almost completely by metal, but when it is formed of a high-refractive-index transparent film, the refractive index difference between the hologram layer 1 and the reflection layer 2 is increased. , A reflection-type relief hologram of a type in which a hologram reproduction image is superimposed on a background that reflects and transmits a part of incident light. As a method of manufacturing such a transmission-type relief hologram, after recording hologram information in a photoresist or the like as an uneven pattern, the uneven pattern is molded by plating or the like, and the mold is formed into a transparent film for forming the hologram layer 1. In general, embossing is performed on a simple resin layer to copy the same, and a method for manufacturing such a reflective relief hologram is to form a hologram layer 1 by using a mold formed in the same manner. Emboss on the transparent resin layer,
A method in which a reflective layer 2 is formed on the copied concavo-convex pattern by vapor deposition or the like;
The reflection layer 2 is formed on a transparent resin layer forming
A method in which a mold in which the above-described concave / convex pattern is formed on the reflective layer 2 is heated and pressed to be duplicated and manufactured (for example,
JP-A-58-65466).

[0004]

As described above, in any of the transmission type relief hologram and the reflection type relief hologram, the gold or the hologram interference fringes are formed in a sheet-like film or a multilayer body as a concavo-convex pattern in the manufacturing stage. The mold needs to be embossed and duplicated.

[0005] By the way, the most typical method for continuously embossing a sheet-like film or a multilayer body as a material of the relief hologram with a mold is to wind the mold around a roll (plate cylinder) and carry out a roll press. It is. For example,
As shown in FIG. 9, a mold 8 having a hologram relief pattern is wound around a plate cylinder 6, and a material sheet 5 (in the illustrated case, a reflection type relief hologram is transferred to a transfer foil). In the case of a type configuration, it comprises a reflective layer 2, a hologram layer 1, a release layer 3, and a base film 4.)
The relief surface of the mold 8 is periodically embossed by applying a high pressure between the plate cylinder 6 and the impression cylinder 7 while heating and rotating as shown by an arrow.

However, as is clear from FIG. 9, it is difficult to continuously form both ends of the mold 8 in the circumferential direction of the plate cylinder 6 without a seam, and the seam 9 is embossed, and as shown in FIG. as indicated, resulting in relief hologram 10, it would appear the hologram area 11 ₁ to 11 ₃ periodically non hologram area or non-relief pattern area 12 ₁ to 12 ₃ between, without continuous seam The subsequent continuous and repeated hologram pattern cannot be obtained.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a relief hologram in which a repetitive pattern continues continuously without a break, and a relief hologram from a mold having a limited size. It is an object of the present invention to provide a method for embossing a hologram.

[0008]

According to the present invention, there is provided a relief hologram having a repetition pattern according to the present invention, wherein an adjacent relief hologram has an uneven pattern corresponding to an interference fringe of one relief hologram at an end and another relief hologram. The uneven pattern corresponding to the interference pattern of the hologram is formed so as to overlap each other.

In this case, as the relief hologram,
There may be a transmission type relief hologram or a reflection type relief hologram.

[0010] The overlapping region of the adjacent relief holograms may be formed in a straight line or in a wavy shape.

Further, in the superimposed region of the adjacent relief holograms, while the one relief hologram reaches the other relief hologram, the depth of the concavo-convex pattern corresponding to the interference fringes of one relief hologram gradually decreases, and If the relief hologram is formed so that the depth of the concavo-convex pattern gradually increases, the reconstructed image from one relief hologram gradually becomes weaker at the overlapping portion, and the reconstructed image from the other relief hologram gradually becomes stronger. Therefore, the overlapping portion is not conspicuous and looks natural visually.

As a method of embossing a relief hologram as described above, two or more dies having an uneven pattern corresponding to interference fringes of the relief hologram are used, and each die is wound around a separate plate cylinder. A common impression cylinder or a separate impression cylinder is pressed against the cylinder to allow the material sheet of the relief hologram to pass through the press area between the plate cylinder and the impression cylinder in order, or to correspond to the interference fringes of the relief hologram. Using two or more dies having a concavo-convex pattern to be formed, each die is wound around a common plate cylinder, and a plurality of impression cylinders are pressed against the plate cylinder, so that a material sheet of a relief hologram is formed with the plate cylinder. The press area between the impression cylinders is passed in order.

In this case, when the front end of the mold enters the press area, the pressure between the plate cylinder and the impression cylinder is gradually increased or the distance between the two is gradually reduced, and the rear end of the mold is pressed into the press area. When entering, when the pressure between the plate cylinder and the impression cylinder is gradually reduced or the distance between both is gradually increased, in the superimposition region of the relief hologram, one relief hologram reaches the other relief hologram. Meanwhile, the relief hologram can be formed such that the depth of the uneven pattern corresponding to the interference fringes of one relief hologram gradually becomes shallow, and the depth of the uneven pattern of the other relief hologram gradually becomes deep.

When the plate cylinder is set rotatably, the impression cylinder is driven to rotate, and the plate cylinder is driven, the press accuracy is improved, and the plate cylinder and the impression cylinder slide and slip. Disappears.

[0015] Further, a mold having an uneven pattern corresponding to the interference fringes of the relief hologram is set in a flat press device, and the material sheet of the relief hologram is pressed in order while being advanced by a distance smaller than the width of the mold. Thus, the relief hologram as described above can be embossed. In this case, by using a mold whose thickness is gradually reduced toward the outside of both ends at the both ends in the width direction of the mold, the one relief hologram reaches the other relief hologram in the overlapping region of the relief hologram. During this time, the relief hologram can be formed such that the depth of the uneven pattern corresponding to the interference fringes of one relief hologram gradually decreases, and the depth of the uneven pattern of the other relief hologram gradually increases.

Further, the relief hologram emboss duplicating plate cylinder according to the present invention is pressed against a rotationally driven impression cylinder, and is driven to rotate with the rotation, thereby forming an uneven pattern corresponding to interference fringes of the relief hologram. A plate cylinder for embossing and duplicating a relief hologram by wrapping a mold around it, a press cylindrical surface portion for wrapping and pressing the mold, and a clamp portion at both ends of the die which cuts out the cylindrical surface and retreats in the central axis direction. And a side plate attached to both ends of the plate cylinder, wherein the side plate has a small circle portion corresponding to the position of the press cylindrical surface portion, a large circle portion corresponding to the mold both end clamp portions, and positions of both ends of the mold. The small circle has a radius from the central axis smaller than the radius of the press cylinder surface, and the radius of the large circle is the press cylinder surface. The radius is set to be greater than the length obtained by adding the thickness of the mold to the radius, and the transition portion gradually increases in radius so as to gradually move from the small circle portion to the large circle portion. A part of the portion is in pressure contact with the impression cylinder. Note that the side plate may have an elliptical shape.

[0017]

In the relief hologram having a repetitive pattern according to the present invention, the adjacent relief hologram has, at its end, an uneven pattern corresponding to the interference pattern of one relief hologram and an uneven pattern corresponding to the interference pattern of the other relief hologram. Are formed so as to overlap each other, so there is no seam between the holograms, so it is not known that a plurality of holograms have been combined into one hologram. The reproduced images appear to be superimposed, which makes the display more preferable as compared with the conventional case where no hologram exists. Depending on the type of pattern recorded on the hologram, there may be cases where the reproduced images on both sides are not noticeable even if they overlap. By devising the shape of the overlapping area and the degree of transition of the relief depth, the overlapping area can be made less noticeable.

[0018]

Next, an embodiment of a relief hologram according to the present invention will be described with reference to FIGS. In the present invention, the relief hologram 10
When embossing, since the seams 12 ₁ to 12 ₃ of the non-hologram area as shown in FIG. 10 between the repetition pattern avoid occurrence, during repeated hologram pattern 11 ₁ to 11 ₃ as shown in FIG. 1 Overlap area 14 _{1 to} 14 ₃
Is provided. In this case, the overlapping areas 14 ₁ to
14 In _3, on both sides of the nature of holograms holograms 11
It will be seen overlap image reproduced from ₁ to 11 _3, as compared with the case where conventional no hologram so, become more preferably as a display member. Depending on the type of pattern recorded on the hologram, there may be cases where the reproduced images on both sides are not noticeable even if they overlap. To inconspicuous more such overlapping area 14 _{1-14 3,} as shown in FIG. 2, instead of linearly provided as shown in FIG. 1, for example may be provided in a wave shape.

[0019] Now, in this way there is no non-hologram area, overlap between the adjacent hologram area 14 _{1-14
In order} to emboss the relief hologram while providing ₃ , when using a roll press, for example, as shown in FIG. 3, use two or more dies 8 ₁ , 8 _{2 in} which interference fringes of the hologram are molded as an uneven pattern. To emboss alternately. That is, the dies 8 ₁ and 8 ₂ are wound around _two plate cylinders 6 ₁ and 6 ₂ , and are pressed against one impression cylinder 7 while being heated at a high pressure. 6 ₁ and between the impression cylinder 7, and then embossed through between the plate cylinder 6 ₂ and the impression cylinder 7, embossed holograms wound by the winding reel 15. Molds 8 _1,
8 ₂ In adjusting the overlapping width between the patterns that are embossed alternately, in order to match the phases, adjusting the roll 13 is arranged between two embossing position. The plate cylinders 6 ₁ and 6 ₂
And the impression cylinder 7, chain to match the peripheral speed, but linking the rotary drive by gears or the like, in practice, may change the thickness of the material sheet 5, the thickness of the mold _81, 82 is changed, The press precision is degraded, slippage occurs between the plate cylinders 6 ₁ and 6 ₂ and the impression cylinder 7, a shift occurs, and the embossed gears may have gears or patterns may not be reproduced. To avoid this, only the impression cylinder 7 is driven to rotate may be the plate cylinder 6 _1, 6 ₂ so as to rotated.

In the case of FIG. 3, the line connecting the centers of the plate cylinders 6 ₁ , 6 _{2 and} the center of the impression cylinder 7 forms a fan-shaped angle. In some cases, it may not be able to bend and be uniformly embossed. To avoid such deflection, as shown in FIG. 4 (a), the plate cylinder ₆₁ both the impression cylinder 7, 6 ₂ is more desirable so as to press from the opposite side. These are the two cylinders 6 ₁ and 6 ₂
In the example shown in FIG. 4B, one plate cylinder 6 and two impression cylinders 7 ₁ and 7 ₂ are used. The dies 8 ₁ and 8 ₂ may be wound around in a circumferential direction. Further, as shown in FIG. 4C, two plate cylinders 6 ₁ and 6 ₂ and two impression cylinders 7 ₁ and 7
Using ₂ in each pair, each plate cylinder 6 _and 62 in the mold _81, 82
May be wound. In the above,
It will be apparent that more than two dies, plate cylinders and impression cylinders may be used.

In order to emboss a relief hologram of a repetitive pattern formed continuously by forming a continuous area by providing an overlapping area as shown in FIGS.
In the case where one mold 8 is used between the flat presses 16 and 17 as shown in FIG.
What is necessary is just to advance step by step by a distance shorter than L for each press.

By the way, in the above example, the overlapping area 14 ₁
In -14 _3, adjacent holograms 11 ₁ to 11 ₃
Was embossed to the same depth as the non-overlapping area. In this case, the reconstructed image of one hologram suddenly appears, and the reconstructed image of the other hologram suddenly disappears, which involves visual unnaturalness. Therefore, as schematically shown in FIG. 6, in the overlapping region 14 _2, when proceeding from one of the hologram 11 ₂ on the other hologram 11 _3, gradually shallower one hologram 11 ₂ embossed depth, reverse to as emboss depth of the other hologram 11 ₃ becomes gradually deeper, it is more desirable to both reproduced image is set to be fade-in fade-out manner. For this purpose, in the case of the flat press method shown in FIG. 5, the vicinity of both ends of the mold 8 may be gradually thinned outward. Also,
In the case of the roll press method shown in FIGS.
_The pressure applied between ₁ , 6 ₂ and the impression cylinders 7 ₁ , 7 ₂ may be reduced when the dies 8 ₁ , 8 ₂ are embossed near both ends. Instead, an impression cylinder 7 having a structure as shown in FIG. 7 may be used.

That is, in FIG. 7, (a) shows the plate cylinder 6
(B) is a cross-sectional view taken along the line BB of (a), (c) is a side view as viewed from the position of the line CC, and the plate cylinder 6 is attached to the center shaft 21. In addition, a heater 22 for heating the mold 8 wound around the surface of the central shaft 21 via the plate cylinder 6 is provided in the central shaft 21.
The plate cylinder 6 includes a press cylindrical surface portion 27 around which the die 8 is wound and pressed, and a die clamp portion 28 which is cut out of the cylindrical surface and retreated in the central axis direction. Clips 29, 30 for attaching both ends of 8
Is provided. Side plates 23 are attached to both ends of the plate cylinder 6. The side plates 23 have a small circle portion 25 corresponding to the position of the press cylindrical surface portion 27 of the plate cylinder 6 and a large circle corresponding to the mold clamp portion 28. A portion 24 and a transition portion 26 corresponding to the positions of both ends of the mold 8 and extending from the small circle portion 25 to the large circle portion 24. The small circle portion 25 has a radius from the central axis 21 for pressing the plate cylinder 6. It is set smaller than the radius of the cylindrical surface 27,
The radius of the great circle portion 24 is the radius of the press cylindrical surface portion 27 and the mold 8
Is set to be longer than the sum of the thicknesses. The radius of the transition portion 26 is gradually increased so as to gradually move from the small circle portion 25 to the large circle portion 24.

Since the plate cylinder 6 is configured as described above,
For example, when the plate cylinders 6 ₁ and 6 ₂ shown in FIG. 3 have such a configuration, when the rear end of _one of the dies 81 enters the press position and exits therefrom, first the metal on the press cylindrical surface portion 27 is pressed. type 8 ₁ and the impression cylinder 7 is jostling at a higher pressure across the sheet material 5, but the plate cylinder ₆₁ with the rotation of the impression cylinder 7 to deeply press the uneven pattern on the sheet material 5 with a driven, then gold Type 8
Transition portion 26 of the side plate 23 in place of ₁ is in direct contact to the impression cylinder 7 across the sheet material 5, since the radius gradually increases, the distance between the plate cylinder ₆₁ and impression cylinder 7 go away, embossing depth for the sheet material 5 of the mold 8 ₁ gradually becomes shallow. The longer the mold 8 ₁ at the position where the great circle 24 is in contact with the impression cylinder 7 is not in a position to emboss the sheet material 5. To the tip of the die ₈₁ comes next, the pressure contact between the large circle 24 and the impression cylinder 7, the plate cylinder ₆₁ is driven to rotate by the rotation of the impression cylinder 7. When the pressing position of the impression cylinder 7 reaches the transition 26 from the large circle portion 24, since the radius contrary to the above is gradually decreased, is gradually deeper embossing depth by the tip of the die 8 ₁ When it comes to the position of the small circle part 25,
Side plates 23 do not longer contact the impression cylinder 7, together with the die ₈₁ and the impression cylinder 7 on the cylindrical surface portion 27 is in contact with high pressure across the sheet material 5, the embossing depth is maximized, the impression cylinder 7 the plate cylinder ₆₁ is rotated by the rotation. On the other hand, since similarly to embossing also in between the plate cylinder 6 ₂ and the impression cylinder 7, at the overlapping portions 14 ₁ to 14 ₃ of the relief hologram 10, as shown in FIG. 6, gradually one hologram 11 ₂ embossed depth It becomes shallow, emboss depth of the other hologram 11 ₃ conversely gradually becomes deeper. In the above, the shape of the side plate 23 does not necessarily have to be as described above. For example, using an elliptical shape, the radius in the long axis direction is made larger than the length obtained by adding the thickness of the mold 8 to the radius of the press cylindrical surface portion 27, and the radius in the short axis direction is made smaller than the radius of the press cylindrical surface portion 27. You may.

As described above, the relief hologram having a repetitive pattern, the emboss duplication method thereof, and the apparatus therefor have been described based on the embodiments. However, the present invention is not limited to these embodiments, and various modifications are possible. It is.

[0026]

As described above, according to the relief hologram having a repetitive pattern according to the present invention, the adjacent relief hologram has, at the end, an uneven pattern corresponding to the interference fringe of one relief hologram and the other relief hologram. Since the concavo-convex pattern corresponding to the interference fringe is formed so as to overlap with each other, there is no seam between the holograms.
It is not known that one hologram is formed by combining a plurality of holograms, and in the overlap region, the images reproduced from the holograms on both sides appear to overlap due to the nature of the hologram, and there is no hologram as in the conventional case. As compared with the case, the display is more preferable. Depending on the type of pattern recorded on the hologram, there may be cases where the reproduced images on both sides are not noticeable even if they overlap. By devising the shape of the overlapping area and the degree of transition of the relief depth, the overlapping area can be made less noticeable.

The relief hologram as described above can be manufactured by various methods and apparatuses as described in the embodiments.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of one embodiment of a relief hologram according to the present invention.

FIG. 2 is a view similar to FIG. 1 of another embodiment according to the present invention;

FIG. 3 is a view for explaining an arrangement of an embodiment of an apparatus for performing an embossed duplication method of a relief hologram according to the present invention.

FIG. 4 is a diagram for explaining a modification of FIG. 3;

FIG. 5 is a view for explaining the arrangement of another embodiment of an apparatus for performing the embossed duplication method of a relief hologram according to the present invention.

FIG. 6 is a view similar to FIG. 1 of yet another embodiment according to the present invention.

FIG. 7 is a view for explaining a configuration of an embodiment of a relief hologram emboss duplication plate cylinder according to the present invention.

FIG. 8 is a diagram showing a cross-sectional structure of a transmission relief hologram and a reflection relief hologram.

FIG. 9 is a view for explaining a relief hologram emboss duplication method using a conventional roll press.

10 is a view similar to FIG. 1 of a relief hologram copied by the method of FIG. 9;

[Explanation of symbols]

5 ... material sheet 6, 6 _1, 6 ₂ ... the plate cylinder 7, 7 _1, 7 ₂ ... the impression cylinder 8, 8 _1, 8 ₂ ... mold 10 ... relief hologram 11 ₁ to 11 ₃ ... hologram pattern 14 _{1-14 3} ... overlapping area 16, 17 ... flat press

Claims (12)

(57) [Claims] 1. An edge of an adjacent relief hologram corresponding to an interference fringe of one relief hologram.
It corresponds to the convex pattern and the interference fringes of the other relief hologram.
Relief hologram of the repeating pattern and uneven pattern that is characterized in that it is formed by being superimposed on each other. 2. The relief hologram having a repeating pattern according to claim 1, wherein the relief hologram is a transmission type relief hologram. 3. The relief hologram having a repeating pattern according to claim 1, wherein the relief hologram is a reflection type relief hologram. 4. The relief hologram having a repetitive pattern according to claim 1, wherein an overlapping region of adjacent relief holograms is formed in a straight line. 5. The relief hologram having a repetitive pattern according to claim 1, wherein an overlapping region of adjacent relief holograms is formed in a wave shape. 6. In a superimposition region of adjacent relief holograms, during a period from one relief hologram to another relief hologram, the depth of a concave / convex pattern corresponding to interference fringes of one relief hologram gradually decreases, and The relief hologram having a repetitive pattern according to any one of claims 1 to 5, wherein the relief hologram is formed so that the depth of the uneven pattern gradually increases. 7. Using two or more dies having an uneven pattern corresponding to interference fringes of a relief hologram, winding each die around a separate plate cylinder, and applying a common impression cylinder or a separate By pressing the impression cylinder, by passing the material sheet of the relief hologram through the press area between the plate cylinder and the impression cylinder in order, the adjacent relief hologram at the end ,
Uneven pattern corresponding to interference fringes of one relief hologram
And the irregularities corresponding to the interference fringes of the other relief hologram
Embossing replication method of relief hologram, wherein a and pattern embossing replicate relief hologram of the repeating pattern being formed by being superimposed on each other. 8. Using two or more dies having an uneven pattern corresponding to interference fringes of a relief hologram, winding each die around a common plate cylinder, and pressing a plurality of impression cylinders against the plate cylinder. Then, by passing the material sheet of the relief hologram sequentially through the press area between the plate cylinder and the impression cylinder, the adjacent relief hologram has one relief at the end.
The uneven pattern corresponding to the interference pattern of the hologram and the other
A relief hologram emboss duplication method, comprising: emboss-duplicating a relief hologram having a repetitive pattern in which concave and convex patterns corresponding to interference fringes of a self- hologram are formed so as to overlap each other. 9. When the leading end of the mold enters the press area, the pressure between the plate cylinder and the impression cylinder is gradually increased or the distance between the two is gradually reduced, and the rear end of the mold enters the press area. 9. The embossed duplication method of a relief hologram according to claim 7, wherein the embossed duplication is performed by gradually reducing the pressure between the plate cylinder and the impression cylinder or gradually extending the distance between them. 10. The printing apparatus according to claim 7, wherein the plate cylinder is rotatably set, the impression cylinder is driven to rotate, and the plate cylinder is driven to perform emboss duplication. Emboss duplication method of relief hologram. 11. A mold having an uneven pattern corresponding to interference fringes of a relief hologram is set in a flat press device,
By successively pressing the material sheet of the relief hologram by a distance smaller than the width of the mold, the adjacent relief hologram is pressed at one end by one of the relief holograms.
Pattern corresponding to the interference fringe of the
An embossed duplication method for a relief hologram, comprising emboss-duplication a relief hologram having a repetitive pattern in which a relief pattern corresponding to interference fringes of a relief hologram is formed so as to overlap each other. 12. The embossed duplication of the relief hologram according to claim 11, wherein the embossed duplication is performed by using a die whose thickness is gradually reduced toward both ends in the width direction at both ends of the die. Method.