JP5240696B1 - Embossing device and embossing method - Google Patents

Abstract

An embossing apparatus and an embossing method capable of forming a fine concavo-convex pattern without unevenness of shallow depth on a sheet, and a printed matter having a fine concavo-convex pattern without unevenness of shallow depth.
A heater, a distance adjusting plate, and a template are provided on a peripheral surface of a heating roller. In the peripheral portion of the template 8, heat escapes more easily than the central portion surrounded by them. Therefore, the heater 6 is divided into a peripheral part and a central part surrounded by the peripheral part, and the heat generation amount per unit area from the peripheral part of the heater 6 is made larger than the heat generation amount per unit area from the central part. Yes.
[Selection] Figure 2

Description

The present invention relates to the embossing unit and embossing of how to embossing the sheet.

  Embossing is known as a technique for forming a pattern having a visual three-dimensional effect on a printed material.

  A device for embossing (embossing machine) includes a heating roller (heating cylinder) and a pressing roller (pressing cylinder). The heating roller and the pressing roller are arranged so that their peripheral surfaces face each other with a minute interval. On the surface (outer peripheral surface) of the heating roller, an embossed plate having fine irregularities is disposed. An accommodation space for accommodating the heater is formed in the peripheral wall of the heating roller.

  The embossing plate is heated by the heat generated from the heater. On the other hand, the heating roller is rotated in a predetermined direction. Then, the sheet is inserted between the heating roller and the pressure roller from the upstream side in the rotation direction of the heating roller, and the heated embossed plate is pressed against the surface of the sheet, thereby corresponding to the unevenness of the embossed plate on the surface of the sheet. Embossing is achieved by forming a fine uneven pattern.

Utility Model Registration No. 3144116 JP 2008-260217 A

  However, it has been found that the uneven pattern formed by the conventional embossing machine has shallow (strong and weak) unevenness. Accordingly, the inventors of the present application have sought the cause of shallow unevenness in the concavo-convex pattern and repeated design changes of the embossing machine, resulting in the present invention.

The present invention has been made under such a background, and its object is a fine rugged pattern is no unevenness of shallow depth can be formed into sheets to provide embossing unit and embossing how That is.

  In order to achieve the above object, an embossing apparatus according to the present invention has a sheet conveying means for conveying a sheet and a mold made of unevenness for embossing in a part of the outermost surface, and the mold is the sheet. A heating roller that is rotated so as to move in the same movement direction as the conveyance direction of the sheet by the conveying means, and a heater that is provided on the heating roller so as to face the mold and that heats the mold. In the heater, the heat generation amount per unit area from at least the downstream end in the moving direction in the peripheral portion is larger than the heat generation amount per unit area from the central portion surrounded by the peripheral portion of the heater.

  The inventors of the present application use a conventional embossing apparatus to heat a mold formed on the outermost surface of the heating roller and press it against the surface of the sheet, thereby forming a fine uneven pattern corresponding to the mold on the surface of the sheet. When it was formed, the inventors discovered that shallow unevenness occurred in the uneven pattern, and investigated the cause of the unevenness. In particular, in micro-embossing, since the uneven pattern is fine, uneven depth of the uneven pattern appears remarkably. Then, the factors that determine the accuracy of embossing include the mold temperature and the pressing force of the mold against the sheet. As the cause of uneven unevenness in the uneven pattern, the direction of movement in the mold (the rotation of the heating roller) It was further found that the downstream end in the direction is cooled by receiving wind. That is, when the downstream end in the moving direction of the mold receives wind, the mold has temperature unevenness, and due to the temperature unevenness, the unevenness pattern formed on the surface of the sheet has shallow unevenness. I found it.

  In addition, the inventors of the present application arrange the heater so as to face the mold, and at least the amount of heat generated per unit area from the downstream end in the moving direction at the peripheral portion of the heater from the central portion surrounded by the peripheral portion. It was considered to make it larger than the calorific value per unit area.

  Thereby, the temperature distribution in the mold can be made uniform. As a result, it is possible to prevent shallow unevenness from occurring in the uneven pattern (including the changing pattern) formed on the surface of the sheet.

  Note that the unevenness of shallow depth in the concavo-convex pattern is not the intentionally formed shallow depth difference but the shallow depth that does not correspond to the unevenness of the mold.

  The peripheral part of the mold is more susceptible to heat escape than the central part surrounded by them. Therefore, the heat generation amount per unit area from the entire peripheral portion of the heater is preferably larger than the heat generation amount per unit area from the central portion of the heater.

  Thereby, the temperature distribution in the mold can be made more uniform. As a result, it is possible to further prevent the occurrence of shallow unevenness in the uneven pattern formed on the surface of the sheet.

  Further, the heat generation amount per unit area from the downstream end portion of the heater may be larger than the heat generation amount per unit area from a portion other than the downstream end portion of the heater. That is, the heat generation amount per unit area from the downstream end of the heater may be the largest.

  The heater may be provided on the peripheral surface of the heating roller. In this case, a template having a mold made of unevenness is provided on the heater.

  In this configuration, the downstream end portion in the moving direction of the heater and the template is easily cooled by receiving wind, and thus unevenness in the depth of the uneven pattern formed on the surface of the sheet is likely to occur. By forming the heat generation amount per unit area from the downstream end of the peripheral edge of the heater larger than the heat generation amount per unit area from the central portion, even in such a configuration, it is formed on the surface of the sheet. It is possible to prevent shallow unevenness from occurring in the uneven pattern.

  Further, unlike the configuration in which a mold made of unevenness is carved on the surface of the heating roller, the uneven pattern formed on the surface of the sheet can be changed by changing the template. Therefore, the cost required for changing the uneven pattern can be reduced.

  The template is preferably made of a thin stainless plate.

  Thereby, a template can be produced at low cost.

  An interval adjusting plate for adjusting an interval between the template and the peripheral surface of the heating roller may be interposed between the heater and the template.

  By adjusting the distance between the template and the peripheral surface of the heating roller, the pressing force of the mold against the sheet can be made appropriate. As a result, it is possible to prevent shallow unevenness from occurring in the uneven pattern formed on the surface of the sheet.

  The embossing method according to the present invention comprises a heating roller rotated in a predetermined direction, a heater provided on the peripheral surface of the heating roller, and a stainless steel thin plate, and a mold made of unevenness for embossing is formed, A method for embossing a sheet using an embossing device comprising a template disposed on the heater, the unit being at least a downstream end portion in the predetermined direction at a peripheral edge of the heater A heating step of heating the template by heating the heater so that the heating value per area is larger than the heating value per unit area from the central portion surrounded by the peripheral edge of the heater; In parallel with the process, a rotation step of rotating the heating roller, a sheet is conveyed in the same direction as the surface of the template rotating with the heating roller, and accompanying the conveyance Te, and a pressing step of pressing the surface of the mold plate on the surface of the sheet.

  According to this method, the heat generation amount per unit area from at least the downstream end in the predetermined direction at the peripheral portion of the heater is made larger than the heat generation amount per unit area from the central portion surrounded by the peripheral portion. Thereby, the temperature distribution in the mold can be made uniform. As a result, it is possible to further prevent shallow unevenness from occurring in the uneven pattern formed on the surface of the sheet.

  The mold formed on the stencil sheet has an embossing mold formed on the entire surface of the concavo-convex area facing the processing target area of the sheet, and a changing pattern formed on a part of the concavo-convex area, and the pattern changes depending on the viewing angle. And a changing mold for forming the film.

In this case, a fine concavo-convex pattern without shallow depth unevenness was formed over the entire area to be processed, and a changing pattern made of a fine concavo-convex pattern without shallow depth unevenness was formed in a part of the processing target area. Ru it is possible to obtain a printed matter.

  According to the present invention, the temperature distribution in the mold can be made uniform. As a result, it is possible to obtain a printed matter having a fine concavo-convex pattern without unevenness in shallow depth.

FIG. 1A is a schematic sectional view showing a schematic configuration of an embossing apparatus according to an embodiment of the present invention, and shows a state before a sheet enters between a heating roller and a pressing roller. FIG. 1B is a schematic cross-sectional view showing a schematic configuration of the embossing apparatus, and shows a state when the sheet starts to enter between the heating roller and the pressing roller. FIG. 1C is an illustrative sectional view showing a schematic configuration of an embossing apparatus according to an embodiment of the present invention, and shows a state in which a sheet enters between a heating roller and a pressing roller. FIG. 1D is an illustrative cross-sectional view showing a schematic configuration of an embossing apparatus according to an embodiment of the present invention, and shows a state after a sheet comes out between a heating roller and a pressing roller. FIG. 2 is a schematic sectional view of the heating roller. FIG. 3 is a diagram for explaining the configuration of the heater. FIG. 4 is a schematic plan view of the template. FIG. 5 is a schematic plan view of the printed matter. FIG. 6 is a diagram for explaining a second configuration of the heater. FIG. 7 is a diagram for explaining a third configuration of the heater. FIG. 8 is a diagram for explaining a fourth configuration of the heater. FIG. 9 is a diagram for explaining a fifth configuration of the heater. FIG. 10 is a diagram for explaining a sixth configuration of the heater. FIG. 11 is a diagram illustrating a surface of a sheet on which a concavo-convex pattern is formed by embossing and microembossing.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  1A, 1B, 1C, and 1D are illustrative sectional views showing a schematic configuration of an embossing apparatus according to an embodiment of the present invention.

  The embossing device 1 is a device for forming a fine uneven pattern on the surface of the sheet S by embossing. Embossing includes microembossing.

  The embossing device 1 includes a heating roller (heating cylinder) 2 and a pressing roller (pressing cylinder) 3. The heating roller 2 is made of metal. The pressure roller 3 is a rubber roller. The heating roller 2 and the pressing roller 3 are provided so as to be rotatable around rotation axes that are parallel to each other, and are arranged so that their peripheral surfaces face each other with a minute interval.

  In addition, the embossing device 1 has a plurality of conveying rollers 4 for conveying the sheet S between the heating roller 2 and the pressing roller 3, and after passing between the heating roller 2 and the pressing roller 3. And a plurality of conveying rollers 5 for conveying the sheet S. The transport rollers 4 and 5 are provided so as to be rotatable around rotation axes that are parallel to the rotation axes of the heating roller 2 and the pressure roller 3, and are arranged in parallel at an appropriate interval.

  FIG. 2 is a schematic sectional view of the heating roller.

  On the peripheral surface of the heating roller 2, a heater 6, a distance adjusting plate 7 and a template 8 are provided. The heater 6, the interval adjusting plate 7, and the template 8 are fixedly attached to the peripheral surface of the heating roller 2.

  The heater 6 has a configuration in which a heating wire (not shown) is sandwiched between two rubber sheets. The heater 6 has, for example, substantially the same width in the circumferential direction of the heating roller 2 and in the rotation axis direction (width direction).

  The interval adjusting plate 7 is stacked on the heater 6. The number of the interval adjusting plates 7 is appropriately determined according to the thickness of the sheet S so that the sheet S passing between the heating roller 2 and the pressing roller 3 is pressed against the template 8 described below with a predetermined pressing force. It is good to be changed to. The interval adjusting plate 7 is made of a flexible iron plate (for example, an iron plate having a thickness of 0.6 mm), and is formed in substantially the same size as the heater 6.

  The template 8 is laminated on the interval adjusting plate 7. The template 8 is made of a stainless steel plate that is substantially the same size as the heater 6.

  The thickness of the template 8 is preferably 0.4 to 1.2 mm. The thickness of the template 8 is preferably a thickness that allows the template 8 to be curved along the peripheral surface of the heating roller 2 (the surface of the interval adjusting plate 7). It is preferable to be within a range of ˜1.2 mm. When the template 8 is manually attached to the heating roller 2, the thickness of the template 8 is preferably 1.0 mm or less.

  When a fine uneven pattern is formed on the surface of the sheet S only by micro embossing, the template 8 can be easily bent along the peripheral surface of the heating roller 2 and the cost of the template 8 can be reduced. The thickness of 8 is preferably 0.4 to 0.8 mm. The uneven pattern formed on the surface of the sheet S by microembossing is an extremely fine pattern, and the depth of the uneven formed on the surface of the template 8 is 0.01 to 0.1 mm. Therefore, if the thickness of the template 8 is 0.4 to 0.8 mm, the surface of the template 8 can be satisfactorily formed on the surface of the template 8 without forming a hole in the concave groove portion. .

  When both embossing and microembossing are performed on one sheet S, the thickness of the template 8 is preferably 0.9 to 1.2 mm. The uneven pattern formed on the surface of the sheet S by embossing is a clear pattern, and the depth of the uneven formed on the surface of the template 8 is 0.2 to 0.8 mm. Therefore, if the thickness of the template 8 is 0.9 to 1.2 mm, the surface of the template 8 can be satisfactorily formed on the surface of the template 8 without forming a hole in the concave groove portion. . As a result, as shown in FIG. 11, both a relatively deep uneven pattern DP by embossing and a relatively shallow uneven pattern SP by microembossing can be satisfactorily formed on the surface of the sheet S.

  FIG. 3 is a diagram for explaining the configuration of the heater.

  The heater 6 is divided into a peripheral part 11 and a central part 12 surrounded by the peripheral part 11.

  The peripheral edge portion 11 and the central portion 12 are provided with heating lines (not shown) independently of each other. The arrangement (density) of the heating lines is designed in the peripheral portion 11 and the central portion 12 so that the heat generation amount per unit area from the peripheral portion 11 is larger than the heat generation amount per unit area from the central portion 12. ing.

  Due to the difference in the heat generation amount per unit area, a temperature difference of, for example, about 20 ° C. occurs between the heat generation temperatures of the peripheral edge portion 11 and the central portion 12. Specifically, under the atmospheric temperature of 25 ° C., the peripheral edge portion 11 and the central portion 12 are heated to, for example, about 100 ° C. and about 80 ° C., respectively.

  In addition, in FIG. 3, in order to distinguish the peripheral part 11 and the center part 12, each part is hatched.

  FIG. 4 is a schematic plan view of the template.

  In the template 8, an embossing die 15 composed of fine irregularities is formed in a plurality of rectangular irregularities A 1 provided in a matrix. Further, a changing die 16 having fine irregularities is formed in a part of the rectangular area A2 in each irregular area A1.

  When embossing the sheet S, the sheet S is conveyed between the heating roller 2 and the pressing roller 3 by the conveying roller 4 as shown in FIG. 1A. On the other hand, the heater 6 is energized and the heating roller 2 is rotated in a predetermined rotation direction R (rotation process). When the heater 6 is energized, the heater 6 generates heat, and the mold 8 is heated by the generated heat (heating process).

  Next, as shown in FIG. 1B, the rotation of the heating roller 2 and the sheet S are adjusted so that the downstream end in the rotational direction R of the template 8 and the downstream end in the moving direction R of the sheet S come into contact with each other. The sheet S is fed between the heating roller 2 and the pressing roller 3 by adjusting the conveyance.

  As shown in FIG. 1C, the sheet S sent between the heating roller 2 and the pressing roller 3 is pressed against the surface of the template 8 that forms the outermost surface of the heating roller 2 (pressing step). Further, it receives heat from the template 8. Thereby, on the surface of the sheet S, as shown in FIG. 5, the uneven pattern 21 by the embossing mold 15 in the uneven area A1 of the template 8 and the changing pattern 22 by the changing mold 16 in the area A2 of the template 8 Is formed.

  Thereafter, the sheet S on which the concavo-convex pattern 21 and the changing pattern 22 are formed is further conveyed downstream in the movement direction R by the conveyance roller 5 as shown in FIG. 1D.

  In the peripheral portion of the template 8, heat escapes more easily than the central portion surrounded by them. Therefore, the heater 6 is divided into the peripheral portion 11 and the central portion 12 surrounded by the peripheral portion 11, and the heat generation amount per unit area from the peripheral portion 11 of the heater 6 is the heat generation amount per unit area from the central portion 12. Has been bigger than.

  Thereby, the temperature distribution in the template 8 can be made uniform. As a result, it is possible to prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  Further, unlike the configuration in which a mold made of unevenness is carved on the surface of the heating roller 2, the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S can be changed by changing the template 8. Therefore, the cost required for changing the uneven pattern 21 and the changing pattern 22 can be reduced.

  Since the template 8 is made of a thin stainless plate, the template 8 can be manufactured at low cost.

  An interval adjusting plate 7 for adjusting the interval between the template 8 and the peripheral surface of the heating roller 2 is interposed between the heater 6 and the template 8.

  By adjusting the distance between the template 8 and the peripheral surface of the heating roller 2, the pressing force of the template 8 (embossing die 15 and changing die 16) against the sheet S can be made appropriate. As a result, it is possible to further prevent occurrence of shallow unevenness in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  As mentioned above, although one Embodiment of this invention was described, this invention can also be implemented with another form.

  For example, in the above-described embodiment, as shown in FIG. 3, the heater 6 is divided into the peripheral portion 11 and the central portion 12, and the density of the heating lines in the peripheral portion 11 and the central portion 12 causes It is assumed that the heat generation amount per unit area is larger than the heat generation amount per unit area from the central portion 12.

  However, the configuration of the heater 6 is not limited to that configuration.

  For example, the density of the heating lines in the peripheral portion 11 and the central portion 12 of the heater 6 is the same, and a controller (temperature controller) that controls energization to the peripheral portion 11 and the central portion 12 is individually provided. The amount of heat generated per unit area from the peripheral portion 11 may be made larger than the amount of heat generated per unit area from the central portion 12 by controlling the respective energization amounts to the portion 11 and the central portion 12.

  Further, when the heating roller 2 rotates, the downstream end portions in the moving direction R of the heater 6 and the template 8 receive wind. Therefore, the temperature of the downstream end portion in the moving direction R of the heater 6 and the template 8 is particularly difficult to increase (the temperature is likely to decrease) compared to other portions.

  Therefore, as shown in FIG. 6, the peripheral edge portion 11 of the heater 6 may be divided into a downstream end portion 11 </ b> A in the moving direction R and the other U-shaped portion 11 </ b> B. Then, the downstream end portion 11A, the U-shaped portion 11B, and the central portion are set so that the heat generation amount per unit area from the downstream end portion 11A is larger than the heat generation amount per unit area from the U-shaped portion 11B. The density of the heating wire in each part of 12 is set, or a controller (temperature controller) for controlling energization to the downstream end 11A, the U-shaped part 11B and the central part 12 is individually provided, Each energization amount to the downstream end portion 11A, the U-shaped portion 11B, and the central portion 12 may be controlled.

  Due to the difference in the heat generation amount per unit area, for example, a temperature difference of about 10 ° C. occurs in the heat generation temperature of the downstream end portion 11A and the U-shaped portion 11B of the peripheral edge portion 11. Further, for example, a temperature difference of about 20 ° C. is generated between the heat generation temperatures of the downstream end portion 11A and the central portion 12 of the peripheral edge portion 11. Specifically, under the atmospheric temperature of 25 ° C., the downstream end portion 11A, the U-shaped portion 11B and the central portion 12 of the peripheral edge portion 11 rise to, for example, about 100 ° C., about 90 ° C. and about 80 ° C., respectively. Warm up.

  Thereby, the temperature distribution in the template 8 can be made more uniform. As a result, it is possible to prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  Further, it is sufficient that the heat generation amount per unit area from at least the downstream end portion 11A of the heater 6 is larger than the heat generation amount per unit area from the central portion 12, and the heat generation amount per unit area from the U-shaped portion 11B. And the calorific value per unit area from the central portion 12 may be the same. In this case, the U-shaped portion 11B and the central portion 12 are not separated, and the heater 6 is divided into a downstream end portion 11A and an upstream portion in the moving direction R with respect to the downstream end portion 11A. It may be configured.

  Furthermore, in the U-shaped portion 11B, the end portions on both sides in the width direction are more likely to escape heat and the temperature is less likely to rise than the portions sandwiched between them.

  Therefore, as shown in FIG. 7, the U-shaped portion 11B is divided into a width direction end portion 11C that is an end portion on both sides in the width direction and a width direction center portion 11D sandwiched between them. Also good. Then, the downstream end portion 11A, the width direction end portion 11C, and the width direction are set so that the heat generation amount per unit area from the width direction end portion 11C is larger than the heat generation amount per unit area from the width direction central portion 11D. The controller which sets the density of the heat generating line in each part of the central part 11D and the central part 12 or controls energization to the downstream end part 11A, the width direction end part 11C, the width direction central part 11D and the central part 12 (Temperature controller) is provided separately, and each energization amount to the downstream end portion 11A, the width direction end portion 11C, the width direction center portion 11D, and the center portion 12 may be controlled.

  Due to the difference in the amount of heat generation per unit area, a temperature difference of about 10 ° C. is generated between the heat generation temperatures of the downstream end portion 11A and the width direction end portion 11C, for example. Further, for example, a temperature difference of about 15 ° C. is generated between the heat generation temperatures of the downstream end portion 11A and the width direction central portion 11D. Further, for example, a temperature difference of about 20 ° C. is generated between the heat generation temperatures of the downstream end portion 11A and the central portion 12. Specifically, under the atmospheric temperature of 25 ° C., the downstream side end portion 11A, the width direction end portion 11C, the width direction center portion 11D, and the center portion 12 are, for example, about 100 ° C., about 90 ° C., and about 85 ° C., respectively. The temperature is raised to about 80 ° C.

  Thereby, compared with the structure shown by FIG. 6, the temperature distribution in the template 8 can be made more uniform. As a result, it is possible to further prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  Further, in the central portion 12, the heat is more likely to escape and the temperature is less likely to increase toward the outer side in the width direction.

  Therefore, as shown in FIG. 8, the peripheral edge portion 11 is divided into a downstream end portion 11A, a width direction end portion 11C, and a width direction center portion 11D, and the center portion 12 is the end portions on both sides in the width direction. You may divide | segment into the width direction edge part 12A and the width direction center part 12B pinched | interposed by them. And the amount of heat generation per unit area decreases in the order of the downstream end portion 11A, the width direction end portion 11C and the width direction center portion 11D of the peripheral edge portion 11, and the width direction end portion 12A and the width direction center portion 12B of the center portion 12. The density of the heat generating lines at the downstream end portion 11A, the width direction end portion 11C and the width direction center portion 11D, and the width direction end portion 12A and the width direction center portion 12B of the center portion 12 is set. Or a controller that controls energization to the downstream end portion 11A, the width direction end portion 11C and the width direction center portion 11D of the peripheral edge portion 11, and the width direction end portion 12A and the width direction center portion 12B of the center portion 12. (Temperature adjusters) are provided individually, and the downstream end 11A, the width direction end 11C, the width direction center 11D and the width direction end 12 of the center 12 of the peripheral edge 11 are provided. And each power supply amount to the width direction center portion 12B is may be controlled.

  Due to the difference in the heat generation amount per unit area, for example, a temperature difference of about 10 ° C. occurs between the heat generation temperatures of the downstream end 11A and the width direction end 11C of the peripheral edge portion 11. Further, for example, a temperature difference of about 15 ° C. is generated between the heat generation temperatures of the downstream end portion 11A and the width direction center portion 11D of the peripheral edge portion 11. Furthermore, for example, a temperature difference of about 20 ° C. is generated between the heat generation temperatures of the downstream end portion 11A of the peripheral portion 11 and the width direction end portion 12A of the central portion 12. Further, for example, a temperature difference of about 25 ° C. is generated between the heat generation temperatures of the downstream end portion 11A of the peripheral portion 11 and the width direction central portion 12B of the central portion 12. Specifically, under an ambient temperature of 25 ° C., the downstream end portion 11A, the width direction end portion 11C and the width direction center portion 11D of the peripheral edge portion 11 and the width direction end portion 12A and the width direction center portion 12B of the center portion 12 are used. Are raised to about 100 ° C., about 90 ° C., about 85 ° C., about 80 ° C. and about 75 ° C., respectively.

  Thereby, compared with the structure shown by FIG. 7, the temperature distribution in the template 8 can be made more uniform. As a result, it is possible to further prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  Further, when the heating roller 2 rotates, the downstream end portions in the moving direction R of the heater 6 and the template 8 receive wind. Therefore, in the heater 6 and the template 8, the temperature at the downstream end in the moving direction R is most difficult to rise. Further, in the portions other than the downstream end portion in the moving direction R in the heater 6 and the template 8, heat is more likely to escape toward the outside in the width direction, and the temperature is less likely to rise.

  Therefore, as shown in FIG. 9, the heater 6 includes a downstream end 31 on the downstream side in the movement direction R and a portion other than the downstream end 31 (upstream in the movement direction R with respect to the downstream end 31. The width direction end portion 32, which is the end portion on both sides in the width direction, and the portion other than the downstream end portion 31 and the width direction end portion 32, that is, the portion sandwiched between the width direction end portions 32 on both sides. You may divide | segment into the width direction center part 33, and may be comprised. The heat generation amount per unit area from the downstream end portion 31 is the largest, and the heat generation amount per unit area from the width direction end portion 32 is larger than the heat generation amount per unit area from the width direction central portion 33. As described above, the density of the heat generation lines in each of the downstream end 31, the width end 32, and the width center 33 is set, or the downstream end 31, the width end 32, and the width center. It is preferable that a controller (temperature controller) for controlling energization to the section 33 is individually provided to control the respective energization amounts to the downstream end portion 31, the width direction end portion 32, and the width direction center portion 33.

  Due to the difference in the amount of heat generated per unit area, a temperature difference of, for example, about 10 ° C. occurs between the heat generation temperatures of the downstream end 31 and the width direction end 32. Further, for example, a temperature difference of about 20 ° C. is generated between the heat generation temperatures of the downstream end portion 31 and the width direction central portion 33. Specifically, under the atmospheric temperature of 25 ° C., the downstream end portion 31, the width direction end portion 32, and the width direction center portion 33 are heated to, for example, about 100 ° C., about 90 ° C., and about 80 ° C., respectively. .

  Thereby, the temperature distribution in the template 8 can be made uniform. As a result, it is possible to prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  Further, in the portions other than the downstream end portion 31 in the moving direction R in the heater 6 and the template 8, heat is more likely to escape and the temperature is less likely to increase toward the outside in the width direction.

  Therefore, as shown in FIG. 10, the portion other than the downstream end portion 31 of the heater 6 (the upstream portion in the movement direction R with respect to the downstream end portion 31) is the outermost end portion on both sides in the width direction. A width direction outermost end portion 34, a width direction outermost end portion 34, an inner side adjacent portion 35 adjacent to the inner side in the width direction, and a width direction central portion 36 that is a portion sandwiched between the inner side adjacent portions 35 on both sides. It may be divided into and. The heat generation amount per unit area from the downstream end portion 31 is the largest, the heat generation amount per unit area from the outermost end portion 34 in the width direction is the next largest, and the heat generation amount per unit area from the inner adjacent portion 35 is The downstream end 31, the outermost end 34 in the width direction, the inner adjacent portion 35, and the center in the width direction so that the heat generation amount is the next largest and the heat generation amount per unit area from the width direction central portion 36 is the smallest. The density of the heat generating line in each part of the part 36 is set, or a controller (temperature) that controls energization to the downstream end 31, the width direction outermost end 34, the inner adjacent part 35, and the width direction center 36. (Adjustment device) is provided individually, and each energization amount to the downstream side end portion 31, the width direction outermost end portion 34, the inner side adjacent portion 35 and the width direction center portion 36 may be controlled.

  Due to the difference in the heat generation amount per unit area, for example, a temperature difference of about 10 ° C. is generated between the heat generation temperatures of the downstream end portion 31 and the width direction outermost end portion 34. Further, for example, a temperature difference of about 15 ° C. is generated between the heat generation temperatures of the downstream end portion 31 and the inner adjacent portion 35. Further, for example, a temperature difference of about 20 ° C. is generated between the heat generation temperatures of the downstream end portion 31 and the width direction center portion 36. Specifically, under the atmospheric temperature of 25 ° C., the downstream side end portion 31, the width direction outermost end portion 34, the inner side adjacent portion 35 and the width direction center portion 36 are, for example, about 100 ° C., about 90 ° C., respectively. The temperature is raised to about 85 ° C and about 80 ° C.

  Thereby, compared with the structure shown by FIG. 9, the temperature distribution in the template 8 can be made more uniform. As a result, it is possible to further prevent shallow unevenness from occurring in the uneven pattern 21 and the changing pattern 22 formed on the surface of the sheet S.

  The heater 6 is not limited to the outer peripheral surface of the heating roller 2 and may be disposed on the inner peripheral surface of the heating roller 2. Further, a space for accommodating the heater 6 may be formed in the peripheral wall of the heating roller 2, and the heater may be accommodated in the space.

  In addition, the heater 6 has a configuration in which the heating wire is sandwiched between two rubber sheets. However, the configuration of the heater 6 is not limited to this, and the heater 6 can be bent along the peripheral surface of the heating roller 2. What is necessary is just to have.

  In addition, various design changes can be made within the scope of matters described in the claims.

1 Embossing device 2 Heating roller 4 Conveying roller (sheet conveying means)
6 Heater 7 Space adjustment plate 8 Mold plate 11 Peripheral part 11A Downstream end part 12 Central part 15 Embossing type 16 Changing type 21 Concavity and convexity pattern 22 Changing pattern 31 Downstream side end part S sheet

Claims (8)

Sheet conveying means for conveying the sheet;
A heating roller that has a mold made of unevenness for embossing on a part of the outermost surface and is rotated so that the mold moves in the same movement direction as the sheet conveyance direction by the sheet conveying means;
A heater provided to face the mold on the heating roller, and for heating the mold;
In the heater, the heat generation amount per unit area from at least the downstream end in the movement direction in the peripheral portion is larger than the heat generation amount per unit area from the central portion surrounded by the peripheral portion.   The embossing apparatus according to claim 1, wherein a heat generation amount per unit area from the peripheral portion of the heater is larger than a heat generation amount per unit area from the central portion of the heater.   3. The embossing according to claim 1, wherein a heat generation amount per unit area from the downstream end portion of the heater is larger than a heat generation amount per unit area from a portion other than the downstream end portion of the heater. Processing equipment. The heater is provided on a peripheral surface of the heating roller;
The embossing apparatus according to any one of claims 1 to 3, further comprising a mold plate made of a thin stainless plate, disposed on the heater, forming the outermost surface of the heating roller, and having the mold formed thereon. .   The mold formed on the template includes an embossing mold formed on the entire surface of the concavo-convex area facing the processing target area of the sheet, and a changing pattern that is formed on a part of the concavo-convex area and changes in pattern depending on the viewing angle. The embossing apparatus according to claim 4, comprising a changing mold for forming a pattern on a sheet.   6. The embossing according to claim 4, further comprising an interval adjusting plate interposed between the heater and the template and adjusting an interval between the template and the peripheral surface of the heating roller. apparatus. A heating plate rotated in a predetermined direction, a heater provided on the peripheral surface of the heating roller, and a mold made of a stainless steel thin plate and formed with unevenness for embossing, and placed on the heater A method for embossing a sheet using an embossing device comprising:
The calorific value per unit area from at least the downstream end in the predetermined direction in the peripheral part of the heater is larger than the calorific value per unit area from the central part surrounded by the peripheral part of the heater. A heating step of heating the template by causing the heater to generate heat;
In parallel with the heating step, a rotation step of rotating the heating roller;
An embossing method comprising: a step of conveying a sheet in the same direction as the surface of the template rotating with the heating roller, and pressing the surface of the template against the surface of the sheet as the sheet is conveyed.   The mold formed on the template includes an embossing mold formed on the entire surface of the concavo-convex area facing the processing target area of the sheet, and a changing pattern that is formed on a part of the concavo-convex area and changes in pattern depending on the viewing angle. The embossing method according to claim 7, comprising a changing mold for forming a pattern on a sheet.