Anti-pressure roller, structure and method

Abstract

A counter-pressure roller (102) is provided for applying pressure to a longitudinal seal (202) of a web of packaging material, the counter-pressure roller (102) comprising a first back panel support (104) having a first radius (R1) and a second back panel support (106) having a second radius (R2) for supporting a first back panel (108) and a second back panel support (110) of the web, respectively, the first radius (R1) being greater than the second radius (R2), a groove (112) disposed between the first back panel support (104) and the second back panel support (106), and defined by first and second edge portions of the first and second back panels (108) and (110). The back panel support member (106) has a first groove edge portion (304) between the first back panel support portion (104) and the bottom portion (302) and a second groove edge portion (306) between the second back panel support portion (106) and the bottom portion (302) and a second groove edge portion (306) between the second back panel support portion (106) and the bottom portion (302) and a first groove edge portion (304) between the first back panel support portion (104) and the bottom portion (302) and a second groove edge portion (306) between the second back panel support portion (106) and the bottom portion (302) and a second groove edge portion (306) between the second back panel support portion (106) and the bottom portion (302) and a second groove edge portion (306)

Description

Technical Field

[0001] The present invention relates to packaging technology. More specifically, it relates to a counter-pressure roller for applying pressure to a longitudinal seal of a web of packaging material.

Background Art

[0002] Currently, in the food industry, an important part of food is the package. The package plays an important role in ensuring the safety of food in addition to product branding and providing information to customers. The packaging material used for the package is designed to have strength and stability so that the package does not break during transportation. Further, the packaging material can form a protective environment for food, for example, to protect food from bacteria, germs, oxygen, sunlight, etc. However, what is important in packaging is not only the packaging material. The package needs to be properly sealed. In a roll-fed system, it is usually done by forming a longitudinal seal along the overlapping portion at both ends of the packaging material to form a tube, and then forming a transverse seal at the lower end of the tube to form a package from the tube.

[0003] The seal of the longitudinal overlap portion has conventionally been performed by applying pressure to two overlapping ends within a segment of a carton package to provide a longitudinal seal strip and sealing them together. The longitudinal seal strip is applied to the overlap portion inside the package to prevent the inner end of the packaging material from contacting the product held therein. When having a carton-based packaging material, the longitudinal seal strip forms a barrier between the food and the carton layer of the packaging material. Thus, using and reliably applying the longitudinal seal strip is an important factor in whether an environmentally friendly food package can be provided.

[0004] To ensure proper longitudinal sealing, current solutions for forming longitudinal seals typically require high pressure. Exposure of components to such high pressures accelerates wear and increases maintenance costs. Furthermore, roll-feed packaging machines are sometimes operated at speeds of up to 30,000 packages per hour. Such high-speed operation presents other challenges; for example, even small errors can quickly lead to machine malfunctions or failures.

[0005] Based on the above, in order to further reduce the need for maintenance and production downtime and to further improve productivity, there is a need to provide a more reliable longitudinal sealing system in roll-feed packaging machines and similar devices. [Overview of the project] [Problems that the invention aims to solve]

[0006] The object of the present invention is to overcome at least partially one or more of the limitations of the prior art described above. In particular, the object is to provide an improved method for forming an anti-pressure roller and a longitudinal seal.

[0007] By providing an asymmetrical anti-pressure roller that takes into account the thickness differences caused by overlapping packaging materials, it was found that pressure can be concentrated in the area related to sealing. This reduces wasted pressure in areas not related to sealing, thus reducing the applied pressure. Furthermore, an improvement in the pressure distribution to the relevant areas is also achieved. [Means for solving the problem]

[0008] According to a first embodiment, an anti-pressure roller is provided for applying pressure to the longitudinal seal of the web of a packaging material. The anti-pressure roller is A first back panel support portion having a first radius and a second back panel support portion having a second radius, for supporting the first back panel and the second back panel of the web, respectively. The first radius is larger than the second radius. A groove is positioned between the first and second back panel support portions to hold the longitudinal overlap portions formed by the first and second edges of the first and second back panels, respectively. Equipped with, The first edge portion is positioned outside the second edge portion such that the first edge portion faces the bottom surface of the groove. The bottom has a third radius which is less than or equal to the second radius. The groove has a first groove edge portion having a first inclination (α) between the first back panel support portion and the bottom surface portion, and a second groove edge portion having a second inclination (β) between the second back panel support portion and the bottom surface portion.

[0009] The second incline may be any angle between 0 and 90 degrees. In other words, the radius of the second back panel support may be the same as the radius of the groove.

[0010] The packaging material may be a multilayer packaging material. It may also include a cardboard layer.

[0011] Making the radius of the first back panel support larger than the radius of the second back panel support is advantageous because it allows overlapping packaging materials to be positioned in a way that compensates for differences in thickness. This allows pressure to be applied to areas on the underside of the overlap that are difficult to seal. Furthermore, the groove helps to position the longitudinal seal so that the applied pressure is evenly distributed.

[0012] The first inclination angle (α) may be 10 to 30 degrees from the central axis of the anti-pressure roller.

[0013] The nip edge may be formed between the first back panel support and the groove such that the nip edge faces the longitudinal seal strip when the longitudinal overlap faces the bottom.

[0014] The advantage of forming a nip edge is that it provides increased back pressure in areas where it is usually difficult to properly form a seal.

[0015] The depth of the groove from the second back panel support to the bottom of the groove may be 1.5 times or less the thickness of the packaging material.

[0016] The bottom of the groove may be positioned closer to the second back panel support than to the first back panel support.

[0017] The first tilt angle (α) may be less than or equal to the second tilt angle (β).

[0018] The second inclination angle (β) may be 80 to 90 degrees from the central axis of the anti-pressure roller so that the second groove edge is positioned opposite the end of the first edge of the packaging material.

[0019] The fact that the second incline is nearly vertical is advantageous in that the edge of the first back panel support (108) faces the second groove edge (306), thus preventing the web of the packaging material from sliding toward the second back panel support (106). Therefore, the correct placement of the longitudinal seal (202) on the anti-pressure roller (102) can be ensured.

[0020] The anti-pressure roller may be made of a highly rigid material. In this case, there is the advantage that the shape of the anti-pressure roller (102) can be prevented from deforming under pressure.

[0021] According to a second embodiment, a pressure roller configuration is provided for applying pressure to the longitudinal seal of a web of packaging material. The pressure roller configuration includes a pair of rollers for applying pressure to the longitudinal seal strip. The pair of rollers comprises a pressure roller and an anti-pressure roller according to the first embodiment, positioned opposite the pressure roller.

[0022] The pressing roller configuration may further include an additional roller pair for applying pressure to the longitudinal overlap portion of the packaging material. The additional roller pair may include an additional pressing roller and an additional counter-pressing roller arranged opposite to the additional pressing roller. The additional roller pair may be arranged to apply an overall pressure to the longitudinal sealing.

[0023] Having the roller pair and the additional roller pair can be advantageous in that the two pairs can concentrate pressure on different regions of the longitudinal seal. By doing so, the pressure wasted in unrelated regions can be reduced.

[0024] The additional roller pair may be arranged upstream of the roller pair.

[0025] A third aspect provides a method for forming a longitudinal seal of a web of packaging material. The method includes receiving a web of packaging material, providing a longitudinal seal strip along one edge of the web of packaging material, forming a tube of the web of packaging material, applying heat to a first edge portion and a second edge portion of the web of packaging material, forming a longitudinal overlap portion between the first edge portion and the second edge portion of the web of packaging material, and supplying the web to a pressure roller configuration, the pressure roller configuration comprising a pair of rollers for applying pressure to the longitudinal seal strip portion, the pair of rollers comprising a pressure roller and an anti-pressure roller positioned opposite the pressure roller for applying pressure to the longitudinal seal of the web of packaging material, the anti-pressure roller comprising a first back panel support portion having a first radius for supporting a first back panel and a second back panel of the web, respectively, and The pressure roller configuration includes a second back panel support having a second radius, the first radius being greater than the second radius, and the second back panel support being positioned between the first back panel support and the second back panel support, and having grooves for holding the longitudinal overlap portion formed by the first edge of the first back panel and the second edge of the second back panel, the first edge being positioned outside the second edge so as to face the bottom of the groove, and the bottom having a third radius which is less than or equal to the second radius, and the groove having a first groove edge having a first inclination (α) between the first back panel support and the bottom, and a second groove edge having a second inclination (β) between the second back panel support and the bottom, and the pressure roller configuration is used to apply pressure along the longitudinal seal so that the first edge, the second edge and the longitudinal seal strip of the web of the packaging material are sealed together.

[0026] The step of applying pressure may include a substep of applying overall pressure to the longitudinal seal by using an additional pair of rollers included in the pressure roller configuration to apply pressure to the longitudinal overlap portion of the packaging material, the additional pair of rollers comprising an additional pressure roller and an additional anti-pressure roller positioned opposite the additional pressure roller, and the additional pair of rollers may be arranged to apply overall pressure to the longitudinal seal.

[0027] The step of supplying the web to the pressure roller configuration may include a sub-step of supplying a longitudinal overlap portion in a groove having a depth from the second back panel support portion to the bottom of the groove that is 1.5 times or less the thickness of the packaging material.

[0028] The step of applying pressure may include a sub-step of aligning the longitudinal seal strip portion with a nip edge formed between the first back panel support portion and the groove.

[0029] Still other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description and the drawings. The same features and advantages described with respect to one aspect are applicable to other aspects as well, unless explicitly stated otherwise.

[0030] Embodiments of the present invention are described by way of example with reference to the accompanying schematic drawings.

Brief Description of the Drawings

[0031] [Figure 1] It is a cross-sectional view showing an example of a counter pressure roller. [Figure 2] It is a view showing different portions of a longitudinal seal between both ends of a web of a packaging material. [Figure 3] It is a view showing different portions and dimensions of a counter pressure roller. [Figure 4] It is a flowchart showing steps of a method for forming a longitudinal seal of a web of a packaging material. [Figure 5a] It is a view showing different examples of the shape of a counter pressure roller. [Figure 5b] It is a view showing different examples of the shape of a counter pressure roller. [Figure 5c] It is a view showing different examples of the shape of a counter pressure roller. [Figure 5d] It is a view showing different examples of the shape of a counter pressure roller. [Figure 5e] It is a view showing different examples of the shape of a counter pressure roller. [Figure 6] This figure shows a pressure roller configuration for applying pressure to the longitudinal seal of the web of packaging material. [Modes for carrying out the invention]

[0032] Figure 1 is a cross-sectional view 100 showing an example of an anti-pressure roller 102 for applying pressure to the longitudinal seal 202 of the web of the packaging material. Furthermore, it is shown that the longitudinal overlap portion 204 of the web of the packaging material may be placed on the anti-pressure roller 102 together with the longitudinal seal strip 118 for forming the longitudinal seal 202.

[0033] The anti-pressure roller 102 has a first back panel support portion 104 for supporting the first back panel 108 of the web. Furthermore, the anti-pressure roller 102 has a second back panel support portion 106 for supporting the second back panel 110 of the web. In this embodiment, the first back panel support portion 104 has a first radius that is larger than the second radius of the second back panel support portion 106.

[0034] After longitudinal and transverse sealing is performed, the first and second back panel portions 104 and 106 can together form the back panel of the package. Currently, it is common for the longitudinal seal to be located on the back panel of the package, meaning that the longitudinal seal is rarely located on the panel intended to face the customer, although this is not essential from a functional standpoint. Therefore, although the portion related to the back panel is referred to herein, it should be understood that the longitudinal seal is not limited to a specific panel of the package.

[0035] Between the first back panel support 104 and the second back panel support 106, the anti-pressure roller 102 is provided with a groove 112. The groove 112 is positioned to hold a longitudinal overlap 204 formed by the first edge of the first back panel support 108 and the second edge of the second back panel support 110. The first edge may be positioned outside the second edge such that the first edge faces the bottom 302 of the groove 112. In this example, the groove 112 has a depth similar to the thickness of the packaging material, so that the second back panel 110 can remain flat on the second back panel support 106 and the bottom 302 of the groove 112. The groove 122 has a first groove edge 304 with a first inclination α and a second groove edge 306 with a second inclination β. In this non-limiting example, the first inclination α is 10 to 30 degrees with respect to the central axis 114 of the anti-pressure roller 102. In this example, the second inclination β is 80-90 degrees from the central axis. In other words, the second groove edge 306 is substantially perpendicular. The first and second edges will be further described in relation to Figure 3.

[0036] A nip edge 116 is formed between the first back panel support portion 104 and the groove 112, such that the nip edge faces the longitudinal seal strip portion. The nip edge 116 can provide a point that increases pressure to ensure a proper seal. The nip edge 116 may be positioned, for example, at the location of the longitudinal seal portion 206 closest to the longitudinal overlap portion 204.

[0037] Figure 2 shows different portions of the longitudinal seal 202 between the two ends of the web of the packaging material. This figure shows portions of the first back panel 108 and the second back panel 110 of the web, as well as the longitudinal seal strip 118, in cross-sectional view. Only the portions where the two ends of the packaging material meet are shown here. It should be understood that the two ends are the opposite ends of the same web of the packaging material, i.e., when joined together, form an inclusion. The longitudinal seal strip 118 is located on the inside of the package.

[0038] In this specification, the longitudinal seal 202 refers to the portion that needs to be sealed. The longitudinal seal 202 comprises a longitudinal overlap portion 204 and a longitudinal seal strip portion 206.

[0039] The longitudinal overlap portion 204 refers to the portion of the longitudinal seal 202 where the first back panel 108 and the second back panel 110 of the web overlap.

[0040] The longitudinal seal strip portion 206 refers to the portion to which the longitudinal seal strip 118 is attached to the first back panel 108 of the web.

[0041] Figure 3 shows different parts and dimensions of the anti-pressure roller 102. The first back panel support 104 may have a first radius, indicated here by R1. Similarly, the second back panel support 106 may have a second radius, indicated by R2. The third radius R3 may be defined as the radius of the anti-pressure roller 102 at the bottom 302 of the groove 112. The depth D4 of the groove 112 may also be defined as the difference between the second radius R2 and the third radius R3. The relationship between the radii may also be formulated as R1 > R2 and R2 ≥ R3, i.e., R1 > R3.

[0042] The groove 112 may be divided into three sections. The first groove edge 304 has a width D1, the second groove edge 306 has a width D2, and the bottom 302 has a width D3. The width D2 may be zero, in which case the second groove edge 306 becomes a vertical edge. The width D3 may also be zero, in which case the bottom 302 may be a single point.

[0043] The first groove edge portion 304 and the second groove edge portion 306 may each have a first inclination α and a second inclination β. The second inclination β can take any value between 0 and 90 degrees. The first inclination α may be smaller than the second inclination β, and both the first and second inclinations may have multiple individual inclinations. In that case, α and β may represent the effective inclination defined by lines between points that define the start and end points of the first groove edge portion 304 and the second groove edge portion 306, respectively.

[0044] Figure 4 is a flowchart showing the steps of a method 400 for forming a longitudinal seal 202 of a web of packaging material, as an example.

[0045] In step 402, the web of packaging material is received.

[0046] In the second step 404, a longitudinal seal strip 118 is provided along one edge of the web of the packaging material.

[0047] In the third step 406, a tube is formed from the web of packaging material.

[0048] In the fourth step 408, heat is applied to the first and second edges of the web of the packaging material.

[0049] In the fifth step 410, a longitudinal overlap portion 204 is formed between the first edge portion 108 and the second edge portion 110 of the web of the packaging material.

[0050] In step 6, step 412, the web of the packaging material is supplied to the pressure roller configuration 600. The pressure roller configuration 600 comprises a pair of rollers 608 for applying pressure to the longitudinal seal strip portion 206. The pair of rollers 608 comprises a pressure roller 610 and an anti-pressure roller 102 positioned opposite the pressure roller 610. The anti-pressure roller 102 comprises a first back panel support portion 104 having a first radius R1 and a second back panel support portion 106 having a second radius R2 for supporting the first back panel 108 and the second back panel 110 of the web, respectively. The first radius R1 may be greater than the second radius R2. The anti-pressure roller 102 further comprises a groove 112 positioned between the first back panel support portion 104 and the second back panel support portion 106 to hold the longitudinal overlap portion 204 formed by the first edge portion of the first back panel 108 and the second edge portion of the second back panel 110, respectively. The first edge portion may be positioned outside the second edge portion such that the first edge portion faces the bottom surface of the groove 112. The bottom portion 302 may have a third radius R3 which is less than or equal to the second radius R2. The groove 112 may include a first groove edge portion 304 having a first inclination α between the first back panel support portion 104 and the bottom portion 302, and a second groove edge portion 306 having a second inclination β between the second back panel support portion 106 and the bottom portion 302.

[0051] In step 7, step 414, the first and second edges of the web of the packaging material, as well as the longitudinal seal strip 118, are sealed together by applying pressure along the longitudinal seal 202 using the pressure roller configuration 600.

[0052] Optionally, the seventh step 414, which applies pressure, may include a substep of applying overall pressure to the longitudinal seal 202 using an additional roller pair 602 configured in the pressure roller configuration 600 to apply pressure to the longitudinal overlap 204 of the packaging material. The additional roller pair 602 may comprise an additional pressure roller 606 and an additional anti-pressure roller 604 positioned opposite the additional pressure roller 606. The additional roller pair 602 may be positioned to apply overall pressure to the longitudinal seal 202. The additional roller pair 602 may be used in the fifth step 412, which forms the longitudinal overlap 204.

[0053] Optionally, the sixth step 412 of supplying the web to the pressure roller configuration 600 may include a substep of supplying the longitudinal overlap portion 204 into the groove 112, which has a depth of no more than 1.5 times the thickness of the packaging material, from the second back panel support portion 106 to the bottom 302 of the groove 112.

[0054] Optionally, the seventh step 414, which applies pressure, may include a substep of aligning the longitudinal seal strip 206 with the nip edge 116 formed between the first back panel support 104 and the groove 112.

[0055] Although the instructions are given in a certain order, the various steps may be performed in other orders, and may also be performed multiple times.

[0056] Figures 5a to 5e show examples of different embodiments of the anti-pressure roller 102. The anti-pressure roller 102 is depicted as a schematic cross-sectional view of the upper part of the anti-pressure roller 102.

[0057] The embodiment of the anti-pressure roller shown in Figure 5a shares many of the features of the anti-pressure roller 102 in Figures 1 and 3. The first back panel support 104 has a larger radius than the second back panel support 106. Furthermore, the inclination of the first groove edge 304 is smaller than the inclination of the second groove edge 306. As a result, the groove bottom 302 is positioned closer to the second back panel support 106 than to the first back panel support 104. In this example, the groove bottom 302 is shown with a width (D3) that is not zero. The groove width (D3) can be any value as long as it is greater than or equal to 0.

[0058] Figure 5b shows that the second groove edge portion 306 is vertical.

[0059] Figure 5c shows an example where the bottom of the groove 302 can be made almost zero compared to the bottom shown in Figures 5a and 5b.

[0060] Figure 5d shows an embodiment where the second inclination is 0 degrees. In other words, the radius of the second back panel support 106 is the same as the radius of the groove bottom 302. For illustrative purposes, the second back panel support 106, the second groove edge 306, and the bottom 302 refer to different parts of the flat surface. However, since these are all part of the same flat surface, how they are divided is irrelevant.

[0061] Figure 5e illustrates that the second groove edge portion 306 can have a gentle slope. In other words, it can have multiple slopes of different values. The same can be applied to the first slope.

[0062] In addition to those shown in Figures 5a to 5e, additional embodiments of the anti-pressure roller are possible. For example, the characteristics shown in one figure may be combined with the characteristics shown in another figure. As a non-limiting example, the second incline may be vertical, as shown in Figure 5b, in combination with the bottom 302 of the groove being a single point, as shown in Figure 5c.

[0063] Figure 6 shows, as an example, a pressure roller configuration 600 for applying pressure to the longitudinal seal 202 of the web of the packaging material.

[0064] The pressure roller configuration 600 may include a pair of rollers 608 for applying pressure to the longitudinal seal strip portion 206. The pair of rollers 608 may include a pressure roller 610 and an anti-pressure roller 102. The anti-pressure roller 102 may be an anti-pressure roller according to the first embodiment. The anti-pressure roller 102 may be positioned on the opposite side of the pressure roller 610 so as to be able to apply pressure to the longitudinal seal 202 of the web of the packaging material passing between the pair of rollers 608.

[0065] The pressure roller configuration 600 may further include an additional pair of rollers 602 for applying pressure to the longitudinal overlap portion 204 of the packaging material. The additional pair of rollers 602 may consist of an additional pressure roller 606 and an additional counter roller 604 positioned opposite the additional pressure roller 606. The additional pair of rollers 602 may be arranged to apply general pressure to the longitudinal seal 202.

[0066] The additional roller pair 602 may be positioned upstream of the roller pair 608. In such a situation, the additional roller pair 602 can apply pressure to a larger portion of the web than the roller pair 608, thereby applying overall pressure first to allow the seal strip to be mounted, and then applying specific pressure to specific sections to allow the seal strip to be mounted further.

[0067] The anti-pressure roller 102 and the additional anti-pressure roller 604 can be made of a highly rigid material so as not to deform under pressure. Furthermore, they can be mounted on a fixed shaft so as to remain in place when pressure is applied.

[0068] The pressure roller 610 and the additional pressure roller 606 can be suspended on a shaft connected to a means for applying pressure. Furthermore, they may be made of a flexible material such as rubber.

[0069] As shown in Figure 6, the different rollers of the pressure roller configuration 600 may have different diameters.

[0070] The pressure roller configuration 600 may be offered in the form of an upgrade kit for an existing roll-feed packaging machine. In other words, the pressure roller configuration is an integral part of the packaging machine and may be incorporated during the assembly of the packaging machine, as well as used to upgrade an existing packaging machine.

[0071] Although various embodiments of the present invention have been described and demonstrated above, the present invention is not limited thereto and can be embodied in other ways within the scope of the subject matter defined in the following claims.

Claims

1. An anti-pressure roller (102) for applying pressure to the longitudinal seal (202) of the web of the packaging material, wherein the anti-pressure roller (102) is A first back panel support portion (104) having a first radius (R1) and a second back panel support portion (106) having a second radius (R2) are provided to support the first back panel (108) and the second back panel (110) of the web, respectively. The first radius (R1) is greater than the second radius (R2), A groove (112) is provided between the first back panel support portion (104) and the second back panel support portion (106) to hold the longitudinal overlap portion (204) formed by the first edge portion of the first back panel (108) and the second edge portion of the second back panel (110), Equipped with, The first edge portion is positioned outside the second edge portion such that the first edge portion faces the bottom portion (302) of the groove (112). The bottom portion (302) has a third radius (R3) which is less than or equal to the second radius (R2), The groove (112) has a first groove edge portion (304) having a first inclination angle (α) between the first back panel support portion (104) and the bottom portion (302), and a second groove edge portion (306) having a second inclination angle (β) between the second back panel support portion (106) and the bottom portion (302). The first inclination angle (α) is less than or equal to the second inclination angle (β). Anti-pressure roller (102).

2. The first inclination angle (α) is 10 to 30 degrees from the central axis (114) of the anti-pressure roller (102). The anti-pressure roller (102) according to claim 1.

3. The nip edge (116) is formed between the first back panel support portion (104) and the groove (112), and when the longitudinal overlap portion (204) is facing the bottom portion (302), the nip edge (116) is facing the longitudinal seal strip portion (206). The anti-pressure roller (102) according to claim 1 or 2.

4. The depth (D4) of the groove (112) from the second back panel support portion (106) to the bottom portion (302) of the groove (112) is 1.5 times or less the thickness of the packaging material. The anti-pressure roller (102) according to any one of claims 1 to 3.

5. The bottom portion (302) of the groove (112) is positioned closer to the second back panel support portion (106) than to the first back panel support portion (104). The anti-pressure roller (102) according to any one of claims 1 to 4.

6. The first inclination angle (α) is smaller than the second inclination angle (β). The anti-pressure roller (102) according to any one of claims 1 to 5.

7. The second inclination angle is 80 to 90 degrees from the central axis (114) of the anti-pressure roller (102) such that the second groove edge portion (306) faces the end of the first edge portion of the packaging material. The anti-pressure roller (102) according to any one of claims 1 to 6.

8. The aforementioned anti-pressure roller (102) is made of a highly rigid material that does not deform under pressure. The anti-pressure roller (102) according to any one of claims 1 to 7.

9. A pressure roller configuration (600) for applying pressure to the longitudinal seal (202) of the web of the packaging material, A pair of rollers (608) for applying pressure to the longitudinal seal strip (206), Equipped with, The aforementioned pair of rollers (608) Pressure roller (610), An anti-pressure roller (102) according to any one of claims 1 to 8, which is positioned opposite to the pressure roller (610), Equipped with, Pressure roller configuration (600).

10. The packaging further comprises an additional pair of rollers (602) for applying pressure to the longitudinal overlap portion (204) of the packaging material, The aforementioned additional roller pair (602) is Additional pressure roller (606), An additional anti-pressure roller (604) is positioned opposite to the additional pressure roller (606), Equipped with, The additional roller pair is positioned to apply overall pressure to the longitudinal seal (202). The pressure roller configuration (600) according to claim 9.

11. The additional roller pair (602) is positioned upstream of the roller pair (608). The pressure roller configuration (600) according to claim 10.

12. A method (400) for forming a longitudinal seal (202) of a web of packaging material, wherein the method is The web of the packaging material is received (402), A longitudinal seal strip (118) is provided along one edge of the web of the packaging material (404), The web of the packaging material forms a tube (406), Heat is applied to the first and second edges of the web of the packaging material (408), A longitudinal overlap portion (204) is formed between the first edge portion and the second edge portion of the web of the packaging material (410), A web is supplied to a pressure roller configuration (600) (412), and the pressure roller configuration comprises a pair of rollers (608) for applying pressure to the longitudinal seal strip portion (206), The aforementioned pair of rollers (608) Pressure roller (610), An anti-pressure roller (102) is positioned on the opposite side of the pressure roller (610) to apply pressure to the longitudinal seal (202) of the web of the packaging material, The anti-pressure roller (102) is equipped with, The web comprises a first back panel support portion (104) having a first radius (R1) and a second back panel support portion (106) having a second radius (R2), respectively, for supporting the first back panel (108) and the second back panel (110) of the web. The first radius (R1) is greater than the second radius (R2), The back panel comprises a groove (112) positioned between the first back panel support portion (104) and the second back panel support portion (106) for holding the longitudinal overlap portion (204) formed by the first edge portion of the first back panel (108) and the second edge portion of the second back panel (110), The first edge portion is positioned outside the second edge portion such that the first edge portion faces the bottom portion (302) of the groove (112). The bottom portion (302) has a third radius (R3) which is less than or equal to the second radius (R2), The groove (112) has a first groove edge portion (304) having a first inclination angle (α) between the first back panel support portion (104) and the bottom portion (302), and a second groove edge portion (306) having a second inclination angle (β) between the second back panel support portion (106) and the bottom portion (302), wherein the first inclination angle (α) is less than or equal to the second inclination angle (β). Using the pressure roller configuration (600), pressure is applied (414) along the longitudinal seal (202) so that the first edge portion, the second edge portion, and the longitudinal seal strip (118) of the web of the packaging material are sealed together. Method (400).

13. The step of applying pressure includes a substep of applying overall pressure to the longitudinal seal (202) using an additional pair of rollers (602) included in the pressure roller configuration (600) to apply pressure to the longitudinal overlap portion (204) of the packaging material, The aforementioned additional roller pair (602) is Additional pressure roller (606), An additional anti-pressure roller (604) is positioned opposite to the additional pressure roller (606), Equipped with, The additional roller pair (602) is positioned to apply overall pressure to the longitudinal seal (202). The method according to claim 12 (400).

14. The step of supplying the web to the pressure roller configuration includes a substep of supplying the longitudinal overlap portion (204) to the groove (112), which has a depth (D4) of 1.5 times or less the thickness of the packaging material, from the second back panel support portion (106) to the bottom portion (302) of the groove (112), The method according to claim 12 (400).

15. The step of applying pressure includes a substep of aligning the longitudinal seal strip portion (206) with the nip edge (116) formed between the first back panel support portion (104) and the groove (112). The method according to any one of claims 12 to 14 (400).

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