A method and apparatus for producing an elastic laminate

Abstract

A method for producing an elastic laminate, comprising: - clamping a first continuous elastic film and a second continuous elastic film (84, 86) in respective clamping zones (68) by respective first and second stretching members (16, 18), - transversely stretching the first continuous elastic film and the second continuous elastic film (84, 86) by rotating the first and second stretching members (16, 18) about respective first and second axes of rotation (20, 22), the first and second axes of rotation being inclined relative to each other, and - releasing the transversely stretched first continuous elastic film and second continuous elastic film (84, 86) from the respective first and second stretching members (16, 18) in respective release zones (70) aligned along a common transverse release line (72).

Description

Technical Field

[0001] The present invention relates to the production of elastic laminates.

[0002] The present invention has been developed specifically for the production of elastic laminates intended for the manufacture of hygiene articles such as absorbent hygiene articles, elastic bands for dressings, etc.

[0003] More specifically, the present invention relates to a method and an apparatus for producing an elastic laminate. Background Art

[0004] To produce hygiene articles such as diapers and other absorbent articles, components with different properties (such as absorbent cores, backsheets, topsheets, elastic waistbands, elastic side sheets, closure structures, elastic barriers for the legs (leg cuffs), etc.) are assembled together.

[0005] Some components of absorbent hygiene articles (such as elastic bands for the legs, elastic leg barriers, elastic side sheets, elastic waistbands, etc.) are made of elastic laminates.

[0006] Depending on the properties of the absorbent hygiene article, the elastic laminate can be produced in various ways. For example, some types of elastic laminates can be formed from one or more nonwoven webs bonded to an elastic film. In certain applications, the elastic film is stretched in the transverse direction before being fixed between two opposing nonwoven webs.

[0007] EP3496687 A1 describes a method and an apparatus for assembling an elastic laminate, in which a first nonwoven web is wound around an outer cylindrical surface of an anvil wheel rotating about a rotation axis, a first elastic film and a second elastic film are stretched in the transverse direction on a first stretching device and a second stretching device, and are applied to the first nonwoven web on the anvil wheel in a first application area and a second application area, the first application area and the second application area being axially and angularly displaced relative to each other with respect to the rotation axis, a second nonwoven web is supplied above the first elastic film and the second elastic film stretched in the transverse direction on the anvil wheel, and the first nonwoven web and the second nonwoven web pass through the first elastic film and the second elastic film and are ultrasonically welded together in a central portion included between the first elastic film and the second elastic film.

[0008] Other similar solutions are disclosed in EP3496688, EP3496689, EP3496690.

[0009] In the solution described in EP3496687 A1, a first elastic film and a second elastic film stretched in the transverse direction are applied to a nonwoven web in two regions offset at an angle to each other. This also poses difficulties in positioning the elastic films relative to the nonwoven web and involves the problem of ensuring an exact spacing between the two elastic films. In addition, arranging two stretching units in two separate regions involves a large size of the production line, which may not be compatible with the size of the manufacturing plant.

[0010] The stretching devices of the prior art are generally interpreted as those shown in EP2260813 B1 Figure 2 wherein a pair of stretching members rotating about respective axes of rotation are driven by respective motors, the axes of rotation being inclined relative to each other, and the motors projecting on opposite sides relative to a central plane extending between the two stretching members. This arrangement requires the operator to perform setting and adjustment operations on both sides of the unit. These operations are usually interrelated, so usually, setting or adjustment on one side is required after setting or adjustment on the other side.

[0011] Another problem with the prior art equipment for producing elastic laminates is poor flexibility. The existing stretching units form a single type of elastic laminate. If the manufacturer intends to expand the product range, production lines usually should be installed for each product to be commercialized. Summary of the Invention

[0012] The present invention aims to provide a method and equipment for producing elastic laminates that overcome the problems of the prior art Brief Description of the Drawings

[0013] The present invention will now be described in detail with reference to the drawings, which are given by way of non-limiting examples only, wherein:

[0014] - Figure 1 is a schematic perspective view of a stretching unit,

[0015] - Figure 2 is a partially sectional perspective view of the stretching unit of claim 1,

[0016] - Figure 3 is a cross-sectional view taken along line III-III of Figure 1 ,

[0017] - Figure 4 is a schematic view of a first embodiment of an equipment for producing elastic laminates,

[0018] - Figure 5 is a schematic plan view showing the operation of the equipment of Figure 4

[0019] - Figure 6Schematic diagram of a second embodiment of an apparatus for producing an elastic laminate, and

[0020] - Figure 7 、 8 Figures 9, 10 are schematic cross-sectional views of different embodiments of elastic laminates that can be produced using the apparatus and methods disclosed herein.

[0021] It should be understood that in the drawings, for simplicity of understanding the drawings, some components may not be shown, and the various drawings may not be drawn to the same scale. Detailed Description

[0022] Referring to Figures 1-3 , numeral 10 denotes a stretching unit for stretching a continuous elastic film in a direction transverse to its longitudinal direction.

[0023] The stretching unit 10 includes a first stretching device 12 and a second stretching device 14. The first stretching device 12 and the second stretching device 14 are substantially identical to each other.

[0024] Each of the first stretching device 12 and the second stretching device 14 includes a first stretching member 16 and a second stretching member 18, which rotate about respective first and second rotational axes 20 and 22 that are inclined relative to each other ( Figure 3 ).

[0025] As shown, the first stretching member 16 and the second stretching member 18 can be disk-shaped. In possible embodiments, the first stretching member 16 and the second stretching member 18 can have shapes different from disk-shaped.

[0026] The first stretching member 16 and the second stretching member 18 have respective outer edges 24, 26, which are provided with clamping elements for clamping the respective side edges of the elastic film. The clamping elements can be suction holes 28 that open on the outer edges 24, 26 and are connected to a pressure source below atmospheric pressure, which will be disclosed hereinafter. Alternatively or in addition to the suction holes 28, the outer edges 24, 26 of the stretching members 16, 18 can be provided with protruding pins that engage the side edges of the elastic film.

[0027] Referring to Figures 1-3 , each of the first stretching device 12 and the second stretching device 14 includes a respective drive assembly 30 that is configured to drive the respective first stretching member 16 and second stretching member 18 to rotate about the respective rotational axes 20, 22.

[0028] The drive assembly 30 of each of the first stretching device 12 and the second stretching device 14 is arranged on only one side with respect to the corresponding stretching members 16, 18. More specifically, the first stretching member 16 and the second stretching member 18 of each of the first stretching device 12 and the second stretching device 14 are located distally and proximally with respect to the corresponding drive assembly 30 respectively, and the drive assembly 30 extends on only one side with respect to the first stretching member 16.

[0029] In the embodiment shown in the drawings, the drive assembly 34 of each of the first stretching device 12 and the second stretching device 14 includes a first motor 32 and a second motor 34 that drive the first stretching member 16 and the second stretching member 18 respectively. Each motor 32, 34 may include respective reduction gears. In each of the first stretching device 12 and the second stretching device 14, the two motors 32, 34 are arranged on only one side with respect to the corresponding stretching members 16, 18.

[0030] In a possible embodiment, the drive assembly 30 of each of the first stretching device 12 and the second stretching device 14 may include a single motor and a connecting assembly that connects the single motor to the corresponding first stretching member 16 and second stretching member 18. In this embodiment, in each of the first stretching device 12 and the second stretching device 14, the single motor and the connecting assembly are arranged on only one side with respect to the corresponding stretching members 16, 18.

[0031] The first motor 32 may be coaxial with the corresponding first stretching member 16 and may be connected to the first stretching member via a first shaft 36. The second motor 34 may be eccentric with respect to the corresponding second stretching member 18 and may be connected to the second stretching member through a second shaft 38 and a belt drive device including a toothed belt 40 and a pair of toothed belt pulleys.

[0032] Referring to Figures 1-3 , the suction holes 28 of each of the first stretching member 16 and the second stretching member 18 communicate with a plurality of connection holes 42 that open on the side surfaces of the corresponding first stretching member 16 and second stretching member 18 facing the drive assembly 30. The connection holes 42 of each of the first stretching member 16 and the second stretching member 18 are pneumatically connected to the corresponding fixed suction chambers 44, 46. The opening sides of the suction chambers face the side surfaces of the corresponding first stretching member 16 and second stretching member 18, and the connection holes 42 open on the side surfaces of the first stretching member and the second stretching member. The suction chambers 44, 46 are connected to a negative pressure source via corresponding tubular elements 48, 50 and a flexible tube (not shown). The suction chambers 44, 46 of each of the first stretching device 12 and the second stretching device 14 are arranged on the side surfaces of the corresponding stretching members 16, 18 facing the corresponding drive assembly 30.

[0033] In a possible embodiment, the fixed suction chambers 44, 46 of each of the first stretching device 12 and the second stretching device 14 are coaxial with the respective first stretching member 16 and second stretching member 18.

[0034] In a possible embodiment, the suction chamber 44 of the first stretching device 16 and the second stretching device 18 is connected to the stretching member 16, which is located distally relative to the respective drive assembly 30. The suction chamber can be selectively connected to and disconnected from a negative pressure source such that the stretching unit 10 can operate only with the external stretching member 18 while the internal stretching member 16 does not work.

[0035] Referring Figures 1-3 , each of the first stretching device 12 and the second stretching device 14 includes a first adjustment mechanism 52 and a second adjustment mechanism 54 respectively associated with the first stretching member 16 and the second stretching member 18.

[0036] Each of the first adjustment mechanism 52 and the second adjustment mechanism 54 is configured to adjust the inclination angle of the rotational axes 20, 22 of the respective first stretching member 16 and second stretching member 18.

[0037] The first adjustment mechanism 52 and the second adjustment mechanism 54 of each of the first stretching device 12 and the second stretching device 14 are arranged on the side of the respective first stretching member 16 and second stretching member 18 facing the respective drive assembly 30.

[0038] Reference Figure 1 and 2, each of the first adjustment mechanism 52 and the second adjustment mechanism 54 includes a base 56 and an adjustable support structure 58. The angular position of the adjustable support structure 58 relative to the base 56 can be adjusted about the respective adjustment axis 60. The angular movement of the adjustable support structure 58 about the adjustment axis 60 can be controlled by a manual actuating rod 62 or a motor (not shown).

[0039] Each adjustable support structure 58 rotatably supports the respective first shaft 36 or second shaft 38. Thus, the angular adjustment of the adjustable support structure 58 about the adjustment axis 60 changes the inclination of the respective first rotational axis 20 or second rotational axis 22.

[0040] The fixed suction chambers 44, 46 of each of the first stretching device 12 and the second stretching device 14 are supported by the adjustable support structures 58 of the respective first adjustment mechanism 52 and second adjustment mechanism 54. Thus, when adjusting the inclination of the rotational axes 20, 22 of the first stretching member 16 and the second stretching member 18, the relative positions between the first stretching member 16 and the second stretching member 18 and the respective fixed suction chambers 44, 46 remain unchanged.

[0041] The base 56 of each of the first adjusting mechanism 52 and the second adjusting mechanism 54 may include a respective guide 64 that allows adjustment of the position of the respective first adjusting mechanism 52 and second adjusting mechanism 54 along the transverse direction Y.

[0042] Each of the first adjusting mechanism 52 and the second adjusting mechanism 54 may include an auxiliary adjusting device 66 that allows adjustment of the position of the respective first tension member 16 and second tension member 18 along a linear direction X and / or Z orthogonal to the transverse direction Y. The auxiliary adjusting device 66 may be manually controlled or controlled by a respective motor (not shown).

[0043] Reference Figure 3 ,each of the first stretching device 12 and the second stretching device 14 has a respective clamping zone 68 and a respective release zone 70.

[0044] The first tension members 16 and the second tension members 18 of each of the first stretching device 12 and the second stretching device 14 are spaced apart from each other in the transverse direction Y, a first distance W1 in the clamping zone 68, and a second distance W2 greater than the first distance W1 in the release zone 70. The distances W1, W2 of the first stretching device 12 and the second stretching device 14 may be equal to or different from each other.

[0045] Specific reference Figure 2 and Figure 3 ,the release zones 70 of the first stretching device 12 and the second stretching device 14 are aligned with each other along a common transverse release line 72.

[0046] Reference Figure 3 ,the first stretching device 12 and the second stretching device 14 are disposed on opposite sides with respect to a central plane 74 orthogonal to the common transverse release line 74. The two first tension members 16 of the first stretching device 12 and the second stretching device 14 that are distal with respect to the respective drive assemblies 30 face opposite sides of the central plane 74.

[0047] In each of the first stretching device 12 and the second stretching device 14, the respective drive assemblies 30, the fixed suction chambers 44, 46, and the adjusting mechanisms 52, 54 extend only on one side of the central plane 74. The drive assemblies 30, the fixed suction chambers 44, 46, and the adjusting mechanisms 52, 54 of the first stretching device 12 and the second stretching device 14 extend on opposite sides of the central plane 74.

[0048] Reference Figure 4 ,the apparatus for producing an elastic laminate is denoted by the reference numeral 76.

[0049] The device 76 includes a first feeding device 78 which is configured to feed a single continuous elastic film 80 in a direction X parallel to its longitudinal axis.

[0050] The device 10 includes a stretching unit 10 as previously disclosed, and the stretching unit includes a first stretching device 12 and a second stretching device 14.

[0051] The single continuous elastic film 80 is longitudinally cut in a longitudinal cutting unit 82, thereby forming a first continuous elastic film 84 and a second continuous elastic film 86, which are fed to the stretching unit 10 by a second feeding device 88.

[0052] The device 10 includes an anvil wheel 90 that can rotate about a transverse rotation axis. The anvil wheel 90 has an outer cylindrical surface provided with suction holes ([ Figure 5 ) pneumatically connected to a negative pressure source 91. The outer cylindrical surface of the anvil wheel 90 is tangent to the common transverse release line 72 of the stretching unit 10.

[0053] The device 10 includes a third feeding device 92 and a fourth feeding device 94 which are configured to feed a first non-woven web 96 and a second non-woven web 98 to the anvil wheel 90 respectively. In a possible embodiment, each of the third feeding device and the fourth feeding device 94 can feed two parallel first non-woven webs 96 and two parallel second non-woven webs 98 to the anvil wheel 90.

[0054] Referring Figure 4 to the rotation direction of the anvil wheel 90 shown by the arrow 100 in [

[0055] The device 76 includes a fastening device 102 that cooperates with the outer cylindrical surface of the anvil wheel 90. The fastening device 102 can be an ultrasonic welding device, a pressure device for fastening by an adhesive, or a thermal or thermo-mechanical welding device.

[0056] The operation of the previously described device 76 is as follows.

[0057] A single continuous elastic film 80 is unwound from a reel and longitudinally cut to form a first continuous elastic film 84 and a second continuous elastic film 86. The first continuous elastic film 84 and the second continuous elastic film 86 may have respective widths W1 that are equal to or different from each other. In a possible embodiment, the first continuous elastic film 84 and the second continuous elastic film 86 may be unwound from respective reels. The first continuous elastic film 84 and the second continuous elastic film 86 may be the same or different from each other, for example, they may be made of materials having different elastic properties.

[0058] Reference Figure 5 , the side edges of the first continuous elastic film 84 and the second continuous elastic film 86 are clamped by the outer edges 24, 26 of the respective first stretching device 12 and second stretching device 14 of the stretching unit 10.

[0059] The first stretching device 12 and the second stretching device 14 pick up the first continuous elastic film 84 and the second continuous elastic film 86 having respective first widths W1 in respective clamping zones 68 and rotate about respective axes of rotation 20, 22. During the rotation of the stretching members 16, 18, the two continuous elastic films 84, 86 are stretched in the transverse direction Y in the path from the respective clamping zones 68 to the respective release zones 70. In the respective release zones 70, the two continuous elastic films 84, 86 have respective widths W2, which may be equal to or different from each other.

[0060] Reference Figure 4 , the first nonwoven web 96 or two parallel first nonwoven webs 96 are applied to the outer cylindrical surface of the anvil wheel 90 at or upstream of a common transverse release line 72.

[0061] The first continuous elastic film 84 and the second continuous elastic film 86 (held stretched in the transverse direction Y) are separated from the outer edges 24, 26 of the respective first stretching member 14 and second stretching member 16 and applied in respective release zones 70, 76 to the first nonwoven web 96 held on the outer cylindrical surface of the anvil wheel 90 or to respective parallel first nonwoven webs 96, the release zones being aligned along the common transverse release line 72. The first continuous elastic film 84 and the second continuous elastic film 86 are held in a laterally stretched state on the outer cylindrical surface of the anvil wheel 90, for example, by suction.

[0062] The fact that the first continuous elastic film 84 and the second continuous elastic film 86 are applied to the first nonwoven web 96 or respective parallel first nonwoven webs 96 along the common transverse release line 72 ensures a high degree of accuracy in the mutual positioning between the two continuous elastic films 84, 86 and the first nonwoven web 96.

[0063] After the first continuous elastic film 84 and the second continuous elastic film 86 are applied to the first nonwoven web 96 on the outer cylindrical surface of the anvil wheel 90 or corresponding parallel first nonwoven webs 96, the second nonwoven web 98 or two parallel second nonwoven webs 98 are applied to the anvil wheel 90 above the two parallel continuous elastic films 84, 86 such that the elastic films 84, 86 elastically stretched in the transverse direction Y are sandwiched between the first nonwoven web 96 and the second nonwoven web 98, or between two pairs of the first nonwoven web 96 and the second nonwoven web 98.

[0064] Then, the nonwoven webs 96, 98 are joined together by a fastening device 102, such as by ultrasonic welding through two parallel continuous first elastic film 84 and second elastic film 86, thereby forming a continuous elastic laminate 104 or two parallel continuous elastic laminates 104.

[0065] Joining the nonwoven webs 96, 98 to each other through the two parallel continuous elastic films 84, 86 includes directly fastening the nonwoven webs 96, 98 through openings in the elastic films 84, 86 and fastening the nonwoven webs 96, 98 on opposite sides of the elastic films 84, 86.

[0066] The fastening device 102 can be configured to form a plurality of connection points that form corresponding holes through the elastic films 84, 86 and directly fix the opposite nonwoven webs 94, 96 to each other by forming holes in the elastic films 84, 86. At the connection points extending through the holes formed in the elastic films 84, 86, the elastic films 84, 86 remain anchored to the nonwoven webs 96, 98. Due to the formation of the holes through the elastic films 84, 86, a breathable elastic laminate is provided.

[0067] Figure 6 A second embodiment of an apparatus 76 for producing an elastic laminate is shown. Elements corresponding to previously disclosed elements are denoted by the same reference numerals.

[0068] In Figure 6 the embodiment, the apparatus 76 includes a transfer wheel 106 disposed between the stretching unit 10 and the anvil wheel 90. The transfer wheel 106 rotates about a rotation axis parallel to the rotation axis of the anvil wheel 90 and has an outer cylindrical surface that is tangent to the outer cylindrical surface of the anvil wheel 90 along a transverse line.

[0069] The conveyor wheel 106 is provided with clamping elements which are configured to hold the first continuous elastic film 84 and the second continuous elastic film 86 that are transversely stretched. In a possible embodiment, the clamping elements may include suction holes opening in the outer cylindrical surface of the conveyor wheel 106 and are pneumatically connected to a negative pressure source for holding the transversely stretched first continuous elastic film 84 and second continuous elastic film 86 by suction. In addition to or instead of the suction holes, the clamping elements may include protruding pins.

[0070] The stretching unit 10 applies the first continuous elastic film 84 and the second continuous elastic film 86 that are transversely stretched onto the outer cylindrical surface of the conveyor wheel 106 in the release zone 70, and the release zone is aligned along a common transverse release line 72. In the release zone 70, the first continuous elastic film 84 and the second continuous elastic film 86 stretched in the transverse direction Y are separated from the first stretching member 16 and the second stretching member 18 of the stretching unit 10 and are brought onto the outer cylindrical surface of the conveyor wheel 106, for example, by suction.

[0071] Then, the first continuous elastic film 84 and the second continuous elastic film 86 stretched in the transverse direction Y are separated from the conveyor wheel 106 and are applied onto the first nonwoven web 96 held on the outer cylindrical surface of the anvil wheel 90 or onto two parallel first nonwoven webs 96. In a possible embodiment, by being first applied to the conveyor wheel 106, the first nonwoven web 96 or two parallel first nonwoven webs 96 may be applied to the outer cylindrical surface of the anvil wheel 90, above the elastically stretched films 84, 86.

[0072] In Figure 6 the embodiment, two parallel continuous elastic films 84, 86 (made of non-porous material) are in direct contact with the outer cylindrical surface of the conveyor wheel 40 without inserting a porous material layer. This allows the continuous elastic films 84, 86 to be held in a transversely stretched state with high precision. In addition, the two parallel continuous elastic films 84, 86 are transferred from the conveyor wheel 106 to the anvil wheel 90 between two tangential cylindrical surfaces, which simplifies the transfer of the elastic films and avoids positioning errors that may occur when the elastic films are applied to the nonwoven web starting from a surface with an inclined axis.

[0073] Referring Figure 6 , the apparatus 76 may include at least one longitudinal cutting device 108 which is configured to cut the transversely stretched continuous elastic films 84, 86 held on the outer cylindrical surface of the conveyor wheel 106 along at least one longitudinal cutting line.

[0074] In a possible embodiment, the stretching unit 10 may apply a single continuous elastic film 80 onto the conveyor wheel 106, and the elastic film is longitudinally cut on the conveyor wheel 106. The single continuous elastic film 80 may be longitudinally cut along a plurality of parallel cutting lines to form more than two parallel continuous elastic films.

[0075] The longitudinal cutting device 108 may include a cutting disk 109 that rotates about an axis parallel to the rotation axis of the conveyor wheel 106. The cutting disk 109 may cooperate with corresponding circumferential slots formed on the outer cylindrical surface of the conveyor wheel 106.

[0076] In a possible embodiment, the device may include a longitudinal cutting device that is arranged to perform longitudinal cutting of one or more continuous elastic films on the anvil wheel 90. The longitudinal cutting device may cut the elastic film without cutting the underlying nonwoven web.

[0077] The device according to the present invention has great flexibility in terms of the possibility of producing different types of elastic laminates.

[0078] Reference Figure 7 , a first embodiment of the elastic laminate 110 includes a first continuous elastic film 84 and a second continuous elastic film 86 sandwiched between first and second wide nonwoven webs 96, 98, and is fixed to the two nonwoven webs 96, 98 by a pattern of connection points 112. The elastic laminate 110 may have an inelastic portion 114 in which the elastic films 84, 86 are laterally spaced apart from each other, and the two nonwoven webs 96, 98 are in direct contact with each other. The two wide nonwoven webs 96, 98 are directly fixed to each other in the inelastic portion 114, which is included between the two parallel continuous elastic films 84, 86 and along the longitudinal edges outside the elastic films 84, 86. The fastening device 102 may be configured to perform a uniform fastening pattern on the entire surface of the nonwoven webs 96, 98, at the elastic films 84, 86, and in the inelastic portion 114.

[0079] The device according to the present invention may include a cutting unit that is configured to form longitudinal weakening lines on the inelastic portion 114, and the weakening lines form preferential fracture lines that allow the two elastic portions of the elastic laminate 104 to separate from each other after the application of a weak separating force.

[0080] Reference Figure 8 , the device according to the present invention may produce two separate continuous elastic laminates 110, each including one continuous elastic film 84, 86 sandwiched between a corresponding first narrow nonwoven web 96 and a second narrow nonwoven web 98. Figure 8Two consecutive elastic laminates 110 can be produced by feeding two separate first narrow nonwoven webs 96 and two separate second narrow nonwoven webs 98 onto an anvil wheel, with the two narrow nonwoven webs being overlapped onto a first continuous elastic film 84 and a second continuous elastic film 86 respectively.

[0081] In Figure 7 and 8 embodiments, the first continuous elastic film 84 and the second continuous elastic film 86 can have the same or different widths, they can be laterally stretched at the same or different stretch ratios W2 / W1, and they can be made of the same or different materials.

[0082] Referring Figure 9 , the apparatus according to the present invention can also produce an elastic laminate 110 having a single wide continuous elastic film 80, with the single wide continuous elastic film being sandwiched between a first wide nonwoven web 96 and a second wide nonwoven web 98. Figure 9 The elastic laminate 110 of

[0083] Referring Figure 10 , the apparatus according to the present invention can also produce an elastic laminate 110 having only one layer of continuous elastic film 84, with the one layer of continuous elastic film being sandwiched between a first wide nonwoven web 96 and a second wide nonwoven web 98, and the two wide nonwoven webs forming wide inelastic portions 116 that extend laterally to the continuous elastic film 84. Figure 10 The elastic laminate 110 of

[0084] The widths of the wide nonwoven webs 96, 98 are greater than the widths of the first continuous elastic film 84 and the second continuous elastic film 86 arranged side by side, the widths of the narrow nonwoven webs 96, 98 are less than the widths of the wide nonwoven webs 96, 98, and are greater than the widths of one continuous elastic film 84, 86.

[0085] The device may include one or two winding units configured to wind one or two elastic laminates 110 around one or two reels.

[0086] Of course, without prejudice to the principles of the present invention, details of the construction and embodiments may vary widely relative to those described and shown, and thus do not depart from the scope of the present invention as defined by the appended claims.

Claims

1. A method for producing an elastic laminate, comprising: providing a first continuous elastic film and a second continuous elastic film and feeding the first continuous elastic film and the second continuous elastic film along respective longitudinal directions parallel to each other, providing a stretching unit including a first stretching device and a second stretching device, each stretching device including a first stretching member and a second stretching member that rotate about respective first and second rotation axes, each of the first stretching device and the second stretching device having a drive assembly disposed on only one side with respect to the respective first stretching member and second stretching member, the first stretching device and the second stretching device having respective clamping zones and respective release zones, wherein the release zones of the first stretching device and the second stretching device are aligned with each other along a common transverse release line, clamping the first continuous elastic film and the second continuous elastic film in the respective clamping zones by the respective first stretching member and second stretching member, transversely stretching the first continuous elastic film and the second continuous elastic film by rotating the first stretching member and the second stretching member about the first rotation axis and the second rotation axis, releasing the transversely stretched first continuous elastic film and second continuous elastic film from the respective first stretching member and second stretching member onto an anvil roll in the respective release zones aligned along the common transverse release line, wherein an outer cylindrical surface of the anvil roll is tangent to the common transverse release line of the stretching unit, applying a nonwoven web on opposite sides of the transversely stretched first continuous elastic film and second continuous elastic film on the anvil roll, and bonding the nonwoven web to the transversely stretched first continuous elastic film and second continuous elastic film on the anvil roll.

2. The method according to claim 1, wherein The first continuous elastic film and the second continuous elastic film are different from each other.

3. The method according to claim 1, wherein, The first continuous elastic film and the second continuous elastic film are obtained by cutting a single continuous elastic film along a longitudinal cutting line.

4. The method according to claim 1, wherein In the respective clamping zones, the first continuous elastic film and the second continuous elastic film have respective widths that are different from each other.

5. The method according to claim 1, wherein, In the respective release zones, the first continuous elastic film and the second continuous elastic film have respective widths that are different from each other.

6. The method according to claim 1, wherein The first continuous elastic film and the second continuous elastic film are transversely stretched at respective different stretching rates.

7. The method according to claim 1, comprising: applying a first nonwoven web of the nonwoven web or a pair of first nonwoven webs of the nonwoven web on the outer cylindrical surface of the anvil roll, applying the transversely stretched first continuous elastic film and second continuous elastic film onto the first nonwoven web or pair of first nonwoven webs held on the outer cylindrical surface of the anvil roll, applying a second nonwoven web of the nonwoven web or a pair of second nonwoven webs of the nonwoven web on the transversely stretched first continuous elastic film and second continuous elastic film on the anvil roll, and bonding the first nonwoven web and the second nonwoven web or a pair of first nonwoven webs and a pair of second nonwoven webs to the transversely stretched first continuous elastic film and second continuous elastic film on the anvil roll.

8. The method according to claim 7, comprising: applying the first and second laterally stretched continuous elastic membranes onto the outer cylindrical surface of a conveyor wheel, and transferring the first and second laterally stretched continuous elastic membranes onto a first nonwoven web or a pair of first nonwoven webs held on the outer cylindrical surface of the anvil wheel.

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