JP2007015322A - Embossing apparatus and embossing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an embossing apparatus capable of forming a desired embossed shape to a base material precisely and efficiently. <P>SOLUTION: The embossing apparatus 10 is equipped with an embossing roll 20 having an embossed shape on its outer periphery and a plurality of the support rolls 30 and 40 provided in opposed relation to the embossing roll and successively grasping the base material 50 fed along the outer periphery of the embossing roll under pressure with respect to the embossing roll. Further, the emboss processing apparatus is equipped with a heater 12 for heating the embossing roll or the support roll on the upstream side. Furthermore, the embossing apparatus is equipped with a cooler 14 for cooling the support roll on the downstream side. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an embossing apparatus and an embossing method for forming a concavo-convex shape on a base material, and more particularly, to an embossing apparatus and an embossing method capable of forming a desired concavo-convex shape on a base material with high accuracy and efficiency. .

Conventionally, with the aim of improving the design of sheet-like materials used for decorative sheets, interior materials, etc., by forming embossed shapes on the substrate surface by embossing using an embossing device, the substrate has a geometric shape. A pattern, a grain pattern, or the like is applied (for example, Patent Documents 1 and 2).
JP-A-6-143466 JP 2002-205311 A

  By the way, when embossing is performed on the base material, the stress remaining on the base material is gradually released after the pressure applied to the base material by the embossing device is released, and accordingly, the base material is once formed on the base material. A phenomenon occurs in which the uneven shape is flattened. Such a phenomenon remarkably occurs when embossing is performed while heating a resin, particularly a thermoplastic resin, as a base material. And when such a phenomenon arises, forming a desired uneven | corrugated shape in a base material with a sufficient precision will be inhibited.

  As a method for avoiding such a problem, for example, it is conceivable that pressure is continuously applied to the base material until the temperature of the base material decreases and the remaining stress is removed. However, such a method is not preferable in that the productivity is remarkably deteriorated.

  The present invention has been made in consideration of such points, and an object thereof is to provide an embossing apparatus and an embossing method that can efficiently form a desired uneven shape on a base material with high accuracy. .

  The embossing device according to the present invention is an embossing device for forming a concavo-convex shape on a substrate, and is an embossing roll having a concavo-convex shape on the outer periphery, and a plurality of support rolls provided facing the embossing roll, A plurality of support rolls that sequentially sandwich the substrate conveyed along the outer periphery of the embossing roll with the embossing roll, a heating device that heats the embossing roll or the upstream support roll, and a most downstream support roll. And a cooling device for cooling. According to such an embossing apparatus, the base material softened by heating is clamped a plurality of times, and an uneven shape can be accurately formed on the base material. Moreover, when it pinches between an embossing roll and the support roll of the most downstream side, a base material is cooled via a support roll. As a result, it is possible to suppress the base material from being flattened as the stress remaining on the base material is gradually released after processing. Furthermore, the tension | tensile_strength to the base material loaded when conveying between each support roll by the pinching pressure by an embossing roll and each support roll is suppressed. Therefore, the substrate is stretched by the tensile force during conveyance, and the uneven shape formed sequentially is displaced and the uneven shape formed on the substrate is suppressed from being flattened. be able to. From these things, according to this embossing method, according to this invention, a desired uneven | corrugated shape can be accurately and efficiently formed in a base material.

  In such an embossing apparatus, the support roll on the most downstream side may be provided with a hole for flowing cooling water. According to such an embossing apparatus, the base material can be cooled to a temperature lower than the softening start temperature by adjusting the temperature, amount, etc. of the cooling water poured into the holes. Thereby, it is possible to prevent the residual stress on the base material from being gradually released and to flatten the base material, and to form a desired uneven shape with higher accuracy.

  In such an embossing apparatus, the most downstream support roll may have a larger diameter than the upstream support roll. According to such an embossing apparatus, the time during which the base material is in contact with the support roll on the most downstream side can be lengthened. Thereby, a base material can be fully cooled via a support roll, without reducing the conveyance speed of a base material.

  In such an embossing apparatus, the surface layer of the support roll on the most downstream side may be formed of a material having a lower hardness than the surface layer of the emboss roll. According to such an embossing apparatus, since the support roll on the most downstream side is easily deformed, the time during which the base material is cooled while being pinched between the emboss roll and the support roll on the most downstream side is lengthened. be able to. Thereby, a base material can be fully cooled through a support roll, maintaining the uneven | corrugated shape formed accurately.

  In the embossing method according to the present invention, a sheet-like base material is sequentially sandwiched between an embossing roll having a concavo-convex shape on the outer periphery and a plurality of support rolls arranged to face the embossing roll, thereby forming a concavo-convex shape on the base material An embossing method for forming a substrate, the step of pressing while heating the substrate between the embossing roll and the uppermost support roll, the step of conveying the substrate along the outer periphery of the embossing roll, and the embossing And a step of clamping the substrate while cooling the substrate between the roll and the most downstream support roll. According to such an embossing method, the base material softened by heating is clamped a plurality of times, and an uneven shape can be accurately formed on the base material. Moreover, since it cools while being pinched between the embossing roll and the support roll on the most downstream side, the base material becomes flat as the stress remaining on the base material is gradually released after processing. Can be suppressed. Furthermore, the tension | tensile_strength to the base material loaded when conveying between each support roll by the pinching pressure by an embossing roll and each support roll is suppressed. Therefore, the substrate is stretched by the tensile force during conveyance, and the uneven shape formed sequentially is displaced and the uneven shape formed on the substrate is suppressed from being flattened. be able to. From these things, according to this embossing method, a desired uneven | corrugated shape can be accurately and efficiently formed in a base material.

  ADVANTAGE OF THE INVENTION According to this invention, it can suppress that the uneven | corrugated shape formed in the base material planarizes after a process, without deteriorating productivity. Thereby, desired uneven | corrugated shape can be accurately and efficiently formed in a base material.

  Embodiments of the present invention will be described below with reference to the drawings.

  1 and 2 are diagrams showing an embodiment of an embossing apparatus and an embossing method according to the present invention.

  Among these, FIG. 1 is a schematic view showing an embossing apparatus 10 and an embossing method, and FIG. 2 is a view for explaining a contact state between the support roll 40 on the most downstream side and the substrate 50.

  As shown in FIG. 1, the embossing device 10 includes a single embossing roll 20 having an uneven shape on the outer peripheral surface, and a plurality of support rolls 30 and 40 each provided facing the embossing roll 20. , A plurality of support rolls 30 and 40 for sequentially pressing the base material 50 conveyed along the outer periphery of the embossing roll 20 between the embossing roll 20, a heating device 12 for heating the embossing roll 20, and the most downstream side And a cooling device 14 that cools the support roll 40. Such an embossing apparatus 10 sequentially presses the sheet-like base material 50 between the embossing roll 20 and the plurality of support rolls 30 and 40 disposed so as to face the embossing roll 20. This is an apparatus for forming an uneven shape on the material 50.

  In addition, as the sheet-like base material 50 to be embossed, for example, a thermoplastic resin made of polypropylene or the like, or a thermoplastic resin laminated on heat-resistant neutral paper is used. A thermoplastic resin has a property of being softened when heated to a temperature higher than a specific softening start temperature and then cured again when cooled to a temperature lower than the softening start temperature.

  The embossing roll 20 is made of a metal roll, for example, and is supported by the drive mechanism 24 via a pair of support shafts 22 protruding from both ends. The drive mechanism 24 can drive the embossing roll 20 at a desired rotational speed.

  In the present embodiment, a first support roll (also referred to as a most upstream support roll) 30 provided on the upstream side and a second support roll (also referred to as a most downstream support roll) provided on the downstream side. Two support rolls composed of 40 are provided. The support rolls 30 and 40 are rotatably held by the holding members 34 and 44 via the support shafts 32 and 42 protruding from both ends. The holding members 34 and 44 can press the support rolls 30 and 40 toward the embossing roll 20 with a desired pressing force.

  The 1st support roll 30 is comprised from the metal roll etc., for example. On the other hand, the 2nd support roll 40 consists of a roll in which the outer surface layer was formed with compressible materials, such as rubber | gum, and the outer surface layer of the 2nd support roll 40 is the embossing roll 20 and the 1st support roll 30. The hardness is lower than that of the outer surface layer.

  Further, as shown in FIG. 1, the embossing roll 20 has a larger diameter than the first supporting roll 30 and the second supporting roll 40, and the second supporting roll 40 is connected to the first supporting roll 30. Compared with a larger diameter.

  As shown in FIG. 1, the heating device 12 is composed of a sheet-like heater built in the embossing roll 20, and mainly heats the outer peripheral surface having the uneven shape of the embossing roll 20. It has become.

  As shown in FIG. 1, the cooling device 14 includes a pump 14 a that sucks and discharges cooling water, and a pair of connecting pipes 14 b that connect the pump 14 a and the second support roll 40. ing. On the other hand, a flow path hole 16 that receives cooling water from the cooling device 14 is formed in the second support roll 40. The flow path hole 16 includes an annular hole 16b formed in the vicinity of the outer peripheral surface of the second support roll 40, and a pair of guide holes 16a communicating with the annular hole 16b and extending to the respective support shafts 42. Yes. The pair of connecting pipes 14b of the pump 14a are rotatably connected to different guide holes 16a of the second support roll 40, respectively. As a result, the pump 14a of the cooling device 14 injects cooling water into the flow path hole 16 from one support shaft 42 of the second support roll 40 via the connecting pipe 14b, and from the other support shaft 42 cooling water. Is supposed to be recovered.

  Moreover, it is preferable that a tank (not shown) is provided in the flow path of the cooling water so that the temperature of the cooling water accumulated in the tank can be adjusted. Thereby, the 2nd support roll 40 can be cooled to desired temperature.

  Next, an embossing method using the embossing apparatus 10 having such a configuration will be described.

  When embossing is performed on the substrate 50, the embossing roll 20 is rotationally driven by the driving mechanism 24 and the vicinity of the outer peripheral surface is heated by the heating device 12. In addition, the cooling water is circulated between the cooling device 14 and the second support roll 40 by the pump 14 a of the cooling device 14, and the vicinity of the outer peripheral surface of the second support roll 40 is cooled by this cooling water. The heating temperature by the heating device 12 and the cooling temperature by the cooling device 14 are set according to the softening start temperature of the base material 50 used.

  In addition, the support rolls 30 and 40 are directed toward the embossing roll 20 by the holding members 34 and 44 so that the base material 50 can be clamped between the embossing roll 20 and the support rolls 30 and 40 with an appropriate pressure. The pressing force to be pressed is adjusted in advance.

  The sheet-like base material 50 is supplied to the embossing apparatus 10 in such a state.

  First, the sheet-like base material 50 is fed between the embossing roll 20 and the first support roll 30. The base material 50 is sandwiched between the embossing roll 20 and the first support roll 30. Thereby, an uneven shape corresponding to the uneven shape of the embossing roll 20 is formed on the substrate 50. Under the present circumstances, the base material 50 is heated via the embossing roll 20 in contact with the embossing roll 20 heated by the heating apparatus 12, Preferably, it heats more than softening start temperature. When the base material 50 is heated above the softening start temperature, the base material 50 is softened and the fluidity is increased, so that the uneven shape can be accurately formed on the base material.

  According to the results of experiments conducted by the present inventors, a large (coarse) uneven shape can be accurately transferred to the substrate 50 by increasing the pressure at the time of clamping, and an appropriate clamping pressure can be increased. By adding time, a small (fine) concavo-convex shape can be accurately transferred to the substrate 50. That is, when the first support roll 30 having a high hardness and a hard-to-deform surface layer is used, the base material 50 can be sandwiched with high pressure, thereby forming a large uneven shape on the base material 50 with high accuracy. can do. On the other hand, when the first support roll 30 having a low hardness and easily deformable surface layer is used, the base material 50 can be pinched for a long time as described in detail later. The uneven shape can be formed with high accuracy.

  After passing between the embossing roll 20 and the first support roll 30, the base material 50 is transported along the outer peripheral surface of the embossing roll 20 and fed between the embossing roll 20 and the second support roll 40.

  Next, the base material 50 is sandwiched again between the embossing roll 20 and the second support roll 40. Thereby, the uneven | corrugated shape of the base material 50 formed between the embossing roll 20 and the 1st support roll 30 fits firmly with the uneven | corrugated shape of the corresponding embossing roll 20 again. Accordingly, the uneven shape corresponding to the uneven shape of the embossing roll 20 is accurately transferred by the base material 50. Thus, the base material 50 on which the concavo-convex shape is accurately formed moves away from the embossing roll 20 and moves along the outer peripheral surface of the second support roll 40.

  During this time, the second support roll 40 in contact with the substrate 50 is cooled by the cooling device 14. Therefore, the substrate 50 is cooled via the second support roll 40. As described above, in the present embodiment, the second support roll 40 has a large diameter and a surface layer made of a material having low hardness. As shown in FIG. 2, the second support roll 40, which has a softer surface layer, is greatly deformed to follow the contour of the outer peripheral surface of the embossing roll 20 as compared with a support roll having a hard surface layer (indicated by a two-dot chain line in FIG. 2). To do. Thereby, the distance (nip length) L1 which the base material 50 moves while being pinched by the embossing roll 20 and the 2nd support roll 40 becomes long. In addition, as shown in FIG. 2, when the large-diameter second support roll 40 is used as compared with the small-diameter support roll (shown by a two-dot chain line in FIG. 2), the base material 50 is the second support roll 40. The distance (contact length) L2 that moves while making contact increases. In addition to these, since the cooling capacity of the cooling device 14 can be adjusted as described above, in the present embodiment, the base material 50 is less than the softening start temperature due to contact with the second support roll 40. Can be cooled.

  The base material 50 thus cooled has an increased deformation resistance and is applied in a state of being heated to a temperature higher than the softening start temperature, and is deformed by the stress remaining inside, that is, the unevenness formed once. The flattening of the shape can be greatly suppressed. In addition, since the base material 50 formed between the embossing roll 20 and the first support roll 30 starts cooling in a state where the base material 50 is firmly fitted to the corresponding embossing roll 20, the base material 50 is formed. The uneven shape is very similar to the uneven shape of the embossing roll and has a clear outline.

  As shown in FIG. 1, the cooled base material 50 is then separated from the second support roll and collected.

  In addition, the movement of the base material 50 described above is not only the rotation of the embossing roll 20 by the driving mechanism 24, but also the upstream of the first support roll 30 for preventing the second support roll 40 from being pulled in and further loosened. Brought by tensioning from the side. Therefore, the sheet-like base material 50 is in a state where a tensile force is constantly applied. However, in the embossing apparatus 10 according to the present embodiment, the base material 50 is sandwiched between the first support roll 30 and the embossing roll 20 and between the second support roll 40 and the embossing roll 20. Yes. Therefore, the tensile force from the upstream side of the first support roll 30 is between the first support roll 30 and the embossing roll 20, and the tensile force from the downstream side of the second support roll 40 is the second support roll 40 and the embossing roll. A large tensile force is not applied to the base material 50 that is tension cut between the first support roll 30 and the second support roll 40 along the outer peripheral surface of the embossing roll 20. Therefore, when it is conveyed from the first support roll 30 to the second support roll 40, the base material 50 is stretched by the tensile force, so that the support rolls 30 and 40 and the embossing roll 20 are sequentially formed. It can be avoided that the uneven shape is displaced.

  Moreover, since the base material 50 is cooled to below the softening start temperature by the contact with the second support roll 40 as described above, the base material 50 is stretched by the tensile force from the downstream side of the second support roll 40, It can suppress significantly that the uneven | corrugated shape formed in the base material 50 planarizes.

  As described above, according to the present embodiment, the plurality of support rolls 30 and 40 are provided facing the embossing roll 20, the heating device 12 heats the embossing roll 20, and the cooling device 14 is on the most downstream side. The support roll (second support roll) 40 is cooled. According to such an embossing apparatus 10, the base material 50 is sequentially sandwiched between the embossing roll 20 and each of the support rolls 30 and 40, so that an uneven shape is formed on the base material 50. Therefore, the base material 50 softened by heating is pinched several times, and a fine uneven shape can be accurately formed on the base material 50. Moreover, when it pinches between the embossing roll 20 and the 2nd support roll 40, the base material 50 is cooled via the 2nd support roll 40, ie, it is firmly with the embossing roll 20 which has an uneven | corrugated shape. The base material 50 is cooled in the fitted state. Therefore, it is possible to suppress the base material 50 from being flattened as the stress remaining on the base material 50 is gradually released after processing. Further, due to the clamping pressure between the embossing roll 20 and the support rolls 30 and 40, the tensile force applied to the base material 50 that is loaded when being transported between the support rolls 30 and 40 is suppressed. Accordingly, the base material 50 is stretched by the tensile force during conveyance, and the uneven shape formed in sequence is displaced, and the uneven shape formed on the base material 50 is flattened. Can be suppressed. From these, it can be said that according to the embossing apparatus in the present embodiment, a desired concavo-convex shape can be accurately and efficiently formed on the substrate 50.

  Further, according to the present embodiment, the second support roll 40 is provided with the flow path hole 16 for circulating the cooling water, and the temperature, amount, etc. of the cooling water poured into the flow path hole 16 are adjusted. By doing, the base material 50 which consists of a thermoplastic resin can be cooled to below softening start temperature. Accordingly, it is possible to prevent the residual stress on the base material 50 from being gradually released and to flatten the uneven shape of the base material 50, and to form a desired uneven shape with higher accuracy. Further, the base material can be cooled in a short time by lowering the cooling water temperature or increasing the cooling water amount. Thereby, the conveyance speed of the base material 50 can be raised, and an uneven | corrugated shape can also be formed more efficiently.

  Furthermore, according to the present embodiment, the second support roll 40 has a larger diameter than the first support roll 30. Therefore, the time during which the base material 50 is in contact with the second support roll 40 can be lengthened. Thereby, the base material 50 can be sufficiently cooled via the second support roll 40 without reducing the conveyance speed of the base material 50.

  Furthermore, according to the present embodiment, the outer surface layer of the second support roll 40 is formed of a material having a lower hardness than the outer surface layer of the embossing roll 20. Accordingly, since the second support roll 40 is easily deformed, it is possible to lengthen the time during which the base material 50 is cooled while being pressed between the embossing roll 20 and the second support roll 40. Thereby, the base material 50 can be sufficiently cooled via the 2nd support roll 40, maintaining the uneven | corrugated shape formed accurately.

  Various modifications can be made to the above-described embodiment within the scope of the present invention. Hereinafter, an example of a modification will be described.

  In the embodiment described above, the example in which the embossing apparatus 10 is provided with the two support rolls 30 and 40 has been described. However, the present invention is not limited thereto, and the embossing apparatus 10 is provided with three or more support rolls. Also good.

  In the above-described embodiment, the example in which the first support roll 30 has the outer surface layer having higher hardness than the second support roll 40 has been described, but the present invention is not limited thereto. The first support roll 30 may have an outer surface layer with low hardness like the second support roll 40. In this case, since the base material 50 is sandwiched and heated between the embossing roll 20 and the first support roll 30 for a longer time, a fine uneven shape is accurately formed on the base material 50. Will come to be. Further, a third support roll is provided between the first support roll 30 and the second support roll 40, the first support roll 30 has an outer surface layer with high hardness, and the third support roll has an outer surface with low hardness. You may make it have a layer. In this case, the base material 50 is accurately formed with a large uneven shape between the embossing roll 20 and the first support roll 30, and further, small (fine) unevenness between the embossing roll 20 and the third support roll. The shape can be formed with high accuracy.

  Furthermore, in embodiment mentioned above, although the heating apparatus 12 showed the example which heats the embossing roll 20, it is not restricted to this. The heating device 12 may heat the support roll that is not connected to the cooling device 14. When three or more support rolls are provided in the embossing device 10, two or more upstream support rolls may be heated by the heating device 12. In such a configuration, the movement of the heat amount to the most downstream support roll 40 is suppressed, and the most downstream support roll 40 can be efficiently cooled by the cooling device 14.

  Further, in the above-described embodiment, the example in which the cooling device 14 cools only the second support roll 40 has been described, but the present invention is not limited thereto. When three or more support rolls are provided in the embossing apparatus 10, the cooling device 14 may cool two or more support rolls.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic which shows one Embodiment of the embossing apparatus and embossing method by this invention. The figure explaining the contact state of the support roll and base material of the most downstream side.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Embossing apparatus 12 Heating apparatus 14 Cooling apparatus 16 Hole 20 Embossing roll 30 Support roll 40 Support roll

Claims (5)

In the embossing device that forms uneven shapes on the substrate,
An embossing roll having an uneven shape on the outer periphery;
A plurality of support rolls provided to face the embossing rolls, and a plurality of support rolls for sequentially pressing the substrate conveyed along the outer periphery of the embossing rolls with the embossing rolls;
A heating device for heating the embossing roll or the upstream support roll;
An embossing device comprising: a cooling device that cools the support roll on the most downstream side.   The embossing apparatus according to claim 1, wherein a hole for flowing cooling water is provided in the most downstream support roll.   The embossing apparatus according to claim 1 or 2, wherein the most downstream support roll has a larger diameter than the upstream support roll.   The embossing apparatus according to any one of claims 1 to 3, wherein the surface layer of the most downstream support roll is formed of a material having a hardness lower than that of the surface layer of the embossing roll. . Embossing that forms an uneven shape on the substrate by sequentially pressing a sheet-like base material between an embossing roll having an uneven shape on the outer periphery and a plurality of support rolls arranged opposite to the embossing roll In the processing method,
A step of pressing while heating the base material between the embossing roll and the uppermost support roll;
Conveying the substrate along the outer periphery of the embossing roll;
A step of clamping the substrate while cooling the base material between the embossing roll and the most downstream support roll.

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