Method of weakening an elastic laminate of an absorbent article, weakening device and absorbent article

Abstract

The present disclosure relates to a method of weakening an elastic laminate of an absorbent article, comprising laminating a garment-side web, a body-side web, and a plurality of elastic filaments to form an elastic laminate; slitting the elastic laminate into a first portion advancing along a machine direction in a first path and a second portion advancing along the machine direction in a second path; and weakening the plurality of elastic filaments within a weak bond area in the first portion of the elastic laminate by a first weakening device arranged in the first path and weakening the plurality of elastic filaments within a weak bond area in the second portion of the elastic laminate by a second weakening device arranged in the second path. Thereby, a more excellent product appearance can be achieved. The present disclosure also relates to a weakening device for use in the above method and an absorbent article made by the above method.

Description

Technical Field

[0001] This invention relates to absorbent articles having an elastic laminate, and more particularly to a method for weakening the elastic laminate in an absorbent article, a weakening apparatus for carrying out the method, and an absorbent article containing the weakened elastic laminate. Background Technology

[0002] One of the primary functions of personal care absorbent products is to retain and absorb bodily waste such as urine, feces, blood, and menstrual blood. Different types of disposable absorbent products have different mechanisms for holding them in place on the wearer. For example, open-back diapers may have one or more Velcro-like fasteners to secure the back of the diaper to the front around the wearer's waist. Other absorbent products, such as diapers or adult pants, may have a front waistband that is permanently attached to a back waistband, with elastic threads extending around the waist opening. These absorbent products are designed to be pulled up, with the elastic threads securing the product firmly around the wearer's waist. Open-back diapers and absorbent pants may also have elastic threads extending along the leg openings to secure the product around the wearer's legs.

[0003] Absorbent materials can be manufactured in a variety of different ways. One common set of manufacturing processes is called the transverse (CD) process. In the transverse process, each of the front and rear waistbands travels along the machine direction during manufacturing, while the absorbent core is applied between the waistbands in the transverse direction of the machine. One of the advantageous features of these types of manufacturing processes is that the elastic yarn can be easily applied to the front and rear waistbands and along the leg openings because the elastic yarn can be applied in the direction of travel of the waistband web.

[0004] However, a disadvantage of these transverse processes is that the elastic yarns applied to the waist section and leg openings can cause the absorbent core to bunch up and / or the outer covering web to wrinkle. In the case of absorbent articles with printed patterns, these patterns may deform due to the bunching of the absorbent core and / or wrinkling of the outer covering in the areas of the printed patterns. Therefore, de-elasticizing or otherwise deactivating or reducing the elastic properties of the elastic yarns at various locations on the absorbent article can reduce the bunching of the absorbent core and / or wrinkling of the outer covering and reduce any deformation of the printed patterns.

[0005] However, weakening the elastic fibers by cutting them can also damage other materials in the elastic laminate, such as the nonwoven fiber web, resulting in a relatively poor aesthetic appearance. Furthermore, the ends of the cut elastic fibers can retract rapidly and uncontrollably, potentially ending up in undesirable positions within the laminate and forming small pieces that can adversely affect comfort, perceived quality, and aesthetics. Additionally, failing the elastic fibers in the elastic laminate can weaken the laminate, making it relatively more prone to tearing, and / or may otherwise lead to control and processing difficulties associated with differential tensile properties within the laminate during subsequent processing.

[0006] To address this deficiency, prior art in Chinese invention patent application publication number CN104203177A teaches a method for creating an elastic laminate by continuously bonding elastic filaments between a first continuous base layer and a second continuous base layer, such that a first base adhesive is continuously applied to the first and / or second continuous base layers with a relatively low basis weight. A second elastic adhesive is also intermittently applied to the elastic filaments. Thus, the elastic laminate includes a first strong bonding region and a second weak bonding region intermittently spaced apart longitudinally. The elastic laminate is then longitudinally cut to form a first continuous elastic laminate and a second continuous elastic laminate, each of which includes a strong bonding region and a weak bonding region. The first and second continuous elastic laminates are then separated laterally from each other. The elastic filaments are then intermittently deactivated by cutting the strands into one or more discrete pieces in the weak bonding regions of the first and second continuous elastic laminates.

[0007] As a result, these discrete pieces of the elastic filament retract and remain within the weakly bonded zone. Although the discrete pieces of the elastic filament are bonded to the first and second substrates by a base adhesive in the weakly bonded zone, the strength of the base adhesive is insufficient to hold the elastic ends of the cut discrete pieces of the elastic filament in proper position on the first and second substrates within the weakly bonded zone. Therefore, the discrete pieces of the elastic filament retract to an unstretched state within the weakly bonded zone. However, the strength of the adhesive in the weakly bonded zone is sufficient to help control the rate of retraction of the discrete pieces. Therefore, the cut elastic pieces can be configured to retract at a controlled rate within the weakly bonded zone, the controlled rate depending in part on the basis weight of the base adhesive applied in the weakly bonded zone, the adhesive coating type, and / or the adhesive type. A relatively slow or rapid retraction rate of the cut elastic pieces can result in improved consistency and / or predictability of the position of the elastic pieces within the completed elastic laminate. The presence of a base adhesive in areas of weak adhesion helps allow the elastic fibers to be cut more evenly, as the adhesive holds the fibers in place long enough for multiple cuts. Furthermore, the adhesive allows the elastic fibers to retract while providing sufficient adhesion to prevent them from detaching from the assembled absorbent article, which could lead to a poor quality impression on the consumer.

[0008] Furthermore, the accompanying drawings of this document illustrate an apparatus for achieving a weakening method, such as cutting, comprising a cutting roller and an anvil roller. The cutting roller is adjacent to the anvil roller and creates a gap defined by a minimum distance between the outer circumferential surfaces of the cutting roller and the anvil roller. The cutting roller may include a plurality of such patterned sections spaced apart from each other along the longitudinal direction of the cutting roller. For example, the cutting roller may have a first set of patterned sections, a region without protrusions, at a first position in the longitudinal direction of the cutting roller, then a second set of patterned sections, a region without protrusions, at a second position in the longitudinal direction of the cutting roller, and finally a second set of patterned sections at a second position in the longitudinal direction of the cutting roller. The dimensions of the regions between adjacent patterned sections may be aligned with the length of the strongly bonded area in the machine direction, such that the protrusions of different sets of patterned sections are aligned with the composite elastic fibers in the weakly bonded area. Typically, the specific arrangement of the protrusions on the surface of the cutting roller may be determined based on which specific composite elastic fibers will be weakened. Thus, the weakening of the elastic laminate can be completed in a single station, and the absorbent core can then be intermittently placed in the weakened elastic laminate. Finally, the elastic laminate with the absorbent core is folded in half so that the part that serves as the back waist area is close to the part that serves as the front waist area, thus obtaining a wearable absorbent product.

[0009] However, in practice, the use of such cutting equipment and methods results in insufficient weakening or uneven cutting of elastic fibers located in multiple weak bonding areas. This causes wrinkles or deformation of printed graphics that are perceptible to consumers at the junction of the absorbent product with the absorbent core in the front or back waist area, thus failing to stimulate consumers' desire to buy.

[0010] Therefore, it is beneficial to provide methods and weakening devices that are configured to minimize the handling of the elastic laminate after intermittently causing the elastic fibers in the elastic laminate to fail; and / or to assemble the elastic laminate in such a manner to maximize the aesthetic appearance of the laminate when placed in an assembled product. Summary of the Invention

[0011] Therefore, the objective of this invention is to provide a method and apparatus for weakening an elastic laminate of an absorbent article, thereby at least partially overcoming the disadvantages of the prior art.

[0012] To accomplish the above-mentioned task, the present invention relates to a method for weakening the elastic laminate of an absorbent article, the method comprising: advancing a garment-side web and a body-side web in a machine direction; advancing a plurality of elastic filaments in a stretched state in the machine direction; continuously applying an adhesive to a first portion of the garment-side web, the body-side web, and at least one of the plurality of elastic filaments to form a strong bonding area; and intermittently applying an adhesive to a second portion of the garment-side web, the body-side web, and at least one of the plurality of elastic filaments to form a weak bonding area, wherein the adhesive surface density in the weak bonding area is less than that in the strong bonding area. The adhesive surface density; the multiple elastic filaments are sandwiched between the garment-side fiber web and the body-side fiber web; the garment-side fiber web, the body-side fiber web, and the multiple elastic filaments are laminated to form an elastic laminate; the elastic laminate is divided into a first part that moves along a first path in the machine direction and a second part that moves along a second path in the machine direction; and the multiple elastic filaments in the weak bonding area of ​​the first part of the elastic laminate are weakened by a first weakening device arranged in the first path and the multiple elastic filaments in the weak bonding area of ​​the second part of the elastic laminate are weakened by a second weakening device arranged in the second path.

[0013] Compared to existing technologies, the method described above for weakening the elastic laminate in absorbent articles significantly achieves miniaturization of the weakening device and shortening of the roller, reducing its length by at least 40% to 60% of that in existing technologies. As a result, under a contact pressure of, for example, 6 bar, the maximum cutter jitter in the method according to the invention is no higher than 0.0066 mm, approximately one-third of the maximum jitter of the cutter in existing technologies, compared to approximately 0.01697 mm. Furthermore, the method according to the invention achieves superior product aesthetics.

[0014] As a preferred aspect of the invention, weakening the multiple elastic wires includes cutting at least one or all of the multiple elastic wires.

[0015] As a preferred aspect of the invention, weakening the multiple elastic fibers includes applying a contact pressure of at least 2.5 bar to the elastic fibers without completely cutting them.

[0016] As a preferred aspect of the invention, at least one or all of the multiple elastic wires are weakened by means of a cutter in the first weakening device and the second weakening device, wherein the vibration of the cutter is not higher than 0.006 mm when the contact pressure is not less than 5 bar.

[0017] As a preferred aspect of the invention, the absorbent article includes a front region, a rear region, and a crotch region arranged in a transverse direction, wherein the first portion is the rear region of the absorbent article and the second portion is the front region and crotch region of the absorbent article.

[0018] As a preferred aspect of the invention, the first and second portions of the elastic laminate are weakened without cutting either the clothing-side web or the body-side web.

[0019] As another aspect of the invention, a weakening device for the above-described method is also provided, comprising: a first weakening roller shaft having a first weakening roller axis; a first bottom roller having a first bottom roller axis arranged in conjunction with the first weakening roller; and a first cutter located outside the circumference of the first weakening roller, wherein the first cutter includes a protrusion having a predetermined pattern located in the middle; and regions without protrusions located on both sides of the first cutter, wherein the first cutter is aligned with the weak bonding area of ​​a first portion of the elastic laminate along the machine direction, and the regions without protrusions are aligned with the strong bonding area of ​​the first portion of the elastic laminate along the machine direction.

[0020] As another aspect of the invention, a weakening device for the above-described method is also provided, comprising: a second weakening roller shaft having a second weakening roller axis; a second bottom roller having a second bottom roller axis arranged in tandem with the second weakening roller; and a second cutter and a third cutter located outside the circumference of the second weakening roller, wherein the second cutter and the third cutter each include protrusions having a predetermined pattern, wherein the second weakening roller is divided along its axial direction into a region without protrusions located in the middle and the second cutter and the third cutter located on both sides thereof, wherein the second cutter and the third cutter are aligned with the weak bonding area of ​​the second portion of the elastic laminate along the machine direction, and the region without protrusions is aligned with the strong bonding area of ​​the second portion of the elastic laminate along the machine direction.

[0021] As a final aspect of the invention, an absorbent article is also provided, comprising a front region, a rear region, a crotch region, and an absorbent core, wherein the front region, the rear region, and the crotch region are all elastic laminates formed by laminating a garment-side fiber web, a body-side fiber web, and multiple elastic fibers; wherein the front region, the rear region, and the crotch region are weakened by the method described above. Attached Figure Description

[0022] Figure 1A It is a plan view of the absorbent article according to the invention in an open and flat configuration, wherein the elastic laminate has not been weakened;

[0023] Figure 1B This is a plan view of the absorbent article according to the invention in an open and flat configuration, wherein the elastic laminate has been weakened;

[0024] Figure 2 This is an overall view of a system for producing absorbent articles having a weakened elastic laminate according to the present invention;

[0025] Figure 3A yes Figure 2 The front view of the first weakening device is shown in the figure;

[0026] Figure 3B yes Figure 2 The rear view of the first weakening device shown in the figure;

[0027] Figure 4A yes Figure 2 A perspective view of the second weakening device shown in the figure;

[0028] Figure 4B yes Figure 2 The front view of the second weakening device is shown in the figure;

[0029] Figure 4C yes Figure 2 The rear view of the second weakening device shown in the figure;

[0030] Figure 5 This is a front view of the weakening mechanism of the second weakening device shown in Figure 4.

[0031] Explanation of reference numerals in the attached figures:

[0032] 10. Body side mesh; 11. Clothing side mesh; 12. Front elastic yarn; 13. Back elastic yarn;

[0033] 14a, 14b. Elastic yarn in the crotch area; 20. Absorbent material; 21. Front area; 22. Back area; 23. Crotch area;

[0034] 211, 221. Weak bonding areas; 212, 222. Strong bonding areas; 21A. Pre-weakening area;

[0035] 22A. Rear weakened area; 23A. First weakened area of ​​the groin region; 23B. Second weakened area of ​​the groin region;

[0036] 24 - Absorbent core; 41, 42, 43, 44, 45, 46 - Applying head; 30 - Upper clamping roller;

[0037] 31. Lower clamping roller; 32. Roller gap; 33. Elastic laminate; 34. Slitting knife;

[0038] L1. First path; L2. Second path; 60. First weakening device; 61. First weakening roller;

[0039] 61A. First upper drive wheel; 62. First weakening roller; 62A. First cutter; 63. First bottom roller;

[0040] 63A. First lower transmission wheel; 64. First base; 65. First adjusting mechanism;

[0041] A1. First weakening roller axis; A2. First bottom roller axis;

[0042] 70. Second weakening device; 71. Second weakening roller; 71A. Second upper drive wheel;

[0043] 72. Second weakening roller; 72A. Second cutter; 72B. Third cutter; 73. Second bottom roller;

[0044] 73A. Second lower drive wheel; 74. Second base; 75. Second adjustment mechanism;

[0045] A3. Second weakening roller axis; A4. Second bottom roller axis; MD. Machine direction; CD. Lateral direction; Detailed Implementation

[0046] Those skilled in the art will understand that the following detailed description of embodiments is merely an illustration of exemplary models and is not intended to limit the broader aspects of this disclosure.

[0047] Certain directional terms used in the description of the accompanying drawings below, such as “inner,” “outer,” “upper,” “lower,” and other directional terms, shall be understood to have their normal meaning and refer to those directions involved when normally viewing the drawings. Unless otherwise specified, the directional terms used in this specification are generally in accordance with the conventional directions understood by those skilled in the art.

[0048] The terms "first," "first," "second," "second," and similar terms used in this invention do not indicate any order, quantity, or importance, but are used to distinguish one component from others. The terms "comprising," "including," and "having" are intended to be inclusive and mean that other elements besides those listed may be present. Many modifications and variations can be made to this invention without departing from its spirit and scope. Therefore, the above illustrative examples should not be used to limit the scope of the invention.

[0049] Terminology Definition

[0050] The term "absorbent article" or "absorbent fabric" as used herein refers to an article that can be placed close to or near the wearer's body (i.e., adjacent to the body) to absorb and contain various liquid, solid, and semi-solid excretions from the body. As described herein, such absorbent articles are intended to be discarded after a limited period of use, rather than washed or otherwise restored for reuse. It should be understood that, without departing from the scope of this disclosure, this disclosure applies to a variety of disposable absorbent articles, including but not limited to diapers, training pants, sports pants, swim trunks, and incontinence products.

[0051] The term "bonding" in this document refers to the joining, adhesion, connection, attachment, etc., of two elements. Two elements are considered to be bonded together when they are joined, adhered, connected, attached, etc., directly or indirectly to each other, such as when bonded to an intermediate element. Bonding can be achieved by, for example, adhesives, pressure bonding, thermal bonding, ultrasonic bonding, binding, stitching, and / or welding.

[0052] The term "carded web" in this document refers to a web made of short fibers that are fed by a carding or combing unit, which separates or spreads the short fibers along the machine direction and aligns them to form a nonwoven web of fibers with a generally machine-oriented orientation. This material can be bonded together by methods including point bonding, air bonding, ultrasonic bonding, and adhesive bonding.

[0053] The term "membrane" as used herein refers to a thermoplastic membrane prepared using extrusion and / or molding methods (e.g., cast film or blown film extrusion). This term includes open-cell membranes, slit membranes, and other porous membranes constituting liquid transfer membranes, as well as membranes that do not transfer fluids, such as, but not limited to, shielding membranes, filled membranes, breathable membranes, and oriented membranes.

[0054] The term “gsm” or “basis weight” in this article refers to grams per square meter.

[0055] The term "hydrophilicity" in this paper refers to the fiber or fiber surface that is wetted by an aqueous liquid in contact with the fiber. Furthermore, the degree of wetting of a material can be described based on the contact angle and surface tension of the liquid and the material involved.

[0056] The term "liquid impermeable" in this document refers to a layer or multilayer laminate in which liquid excretions, such as urine, do not penetrate the layer or laminate in a direction generally perpendicular to the plane of the layer or laminate at the point of liquid contact, under normal conditions of use.

[0057] The term "liquid-permeable" in this document refers to any non-liquid-impermeable material.

[0058] The term "meltblown nonwoven fabric" herein refers to fibers formed by extruding molten thermoplastic material as molten fibers or filaments through multiple thin, typically circular, die capillaries into a converging, high-speed flow of hot gas (e.g., air). The airflow weakens the fibers of the molten thermoplastic material to reduce their diameter, which can be the diameter of a microfiber. The meltblown fibers are then carried by the high-speed gas flow and deposited on a collecting surface to form a web of randomly dispersed meltblown fibers. The meltblown fibers are microfibers, which can be continuous or discontinuous, typically less than about 0.6 denier, and can be adhesive and self-adhesive when deposited on the collecting surface.

[0059] The term "nonwoven" in this document refers to materials and webs formed without the aid of textile weaving or knitting processes. Materials and webs can have a structure of individual fibers, filaments, or threads (collectively referred to as "fibers"), which can be interwoven, but not in a manner as identifiable as in knitted fabrics. Nonwoven materials or webs can be formed by a variety of processes, such as, but not limited to, meltblown, spunbond, and carded web processes.

[0060] The term "spunbond web" herein refers to small-diameter fibers formed by extruding molten thermoplastic material as filaments from multiple fine capillaries of a spinneret having a circular or other configuration, wherein the diameter of the extruded filaments is then rapidly thinned by conventional methods (e.g., draw-out stretching). Spunbond fibers are typically continuous and generally have an average denier greater than about 0.3, and in examples, between about 0.6, 5, and 10 and about 15, 20, and 40. Spunbond fibers are generally non-sticky when deposited on a collection surface.

[0061] The term "superabsorbent" herein refers to a water-swellable, water-insoluble organic or inorganic material that, under most favorable conditions, can absorb at least about 15 to at least about 30 times its own weight (in one embodiment) in an aqueous solution containing 0.9% (by weight) sodium chloride. Superabsorbent materials can be natural, synthetic, and modified natural polymers and materials. Alternatively, superabsorbent materials can be inorganic materials such as silica gel, or organic compounds such as cross-linked polymers.

[0062] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. However, the embodiments are not limited to the following content, and can be arbitrarily modified and implemented within the scope without affecting the spirit of the present invention.

[0063] The present invention provides an absorbent article 20 having an elastic laminate, wherein the absorbent article 20 has a machine direction MD and a transverse direction CD perpendicular to the machine direction MD. For example... Figure 1A and Figure 1B As shown, the absorbent article 20 is exemplarily presented as a three-piece design, including a front area 21, a rear area 22 arranged in the transverse direction, and an absorbent core 24 located in the crotch area 23. The absorbent core 24 is a main component containing an absorbent structure, specifically including: a surface layer, a conductive layer, an absorbent core, a waterproof membrane, and side leak-proof features. It is known that the absorbent core 24 is fixed to the front area 21 and the rear area 22 by adhesive application. In this embodiment, the opposite sides of the front area 21 and the rear area 22, perpendicular to the paper surface, are wrapped upwards and bonded to the upper surface of the absorbent core 24 by hot melt adhesive. The wrapped side is the body side when worn (i.e., the front side along the paper surface), and the side away from the wrapped side is the clothing side when worn.

[0064] Here, the front area 21 is designed as the abdominal waist circumference of the absorbent article 20 when worn, and the rear area 22 is designed as the hip waist circumference of the absorbent article 20 when worn. Both the front area 21 and the rear area 22 include a body-side fiber web 10, a garment-side fiber web 11, and multiple elastic filaments 12 and 13 extending along the length direction and distributed between the garment-side fiber web 11 and the body-side fiber web 10. As a result, the front area 21 and the rear area 22 of the absorbent article 20 are both designed as an elastic laminate formed by the body-side fiber web 10, the front area elastic filaments 12 and the rear area elastic filaments 13, and the garment-side fiber web 11.

[0065] exist Figure 2 The diagram shows a system for producing the absorbent article 20 of the aforementioned elastic laminate, wherein in Figure 2 The portion starting from the left side is used to form an elastic composite made of body side fiber mesh 10, front zone elastic yarn 12 and back zone elastic yarn 13 and clothing side fiber mesh 11, wherein these elastic composites are used to securely hold the absorbent product 20 around the wearer's waist.

[0066] To form the elastic laminate 33, both the body-side web 10 and the garment-side web 11 can be fed into the roll gap 32 located between the upper clamping roller 30 and the lower clamping roller 31 for lamination. For example, multiple front zone elastic yarns 12, back zone elastic yarns 13, and crotch zone elastic yarns 14a to 14b can also be fed into the roll gap 32 between the body-side web 10 and the garment-side web 11 to form the elastic laminate 33.

[0067] The body-side fiber mesh 10 can be made of a variety of materials, such as synthetic fibers (e.g., polyester or polypropylene fibers), natural fibers (e.g., wood or cotton fibers), combinations of natural and synthetic fibers, porous foam, mesh foam, open-cell plastic films, etc. Examples of suitable materials include, but are not limited to, rayon, wood, cotton, polyester, polypropylene, polyethylene, nylon or other heat-bonding fibers, polyolefins, such as, but not limited to, copolymers of polypropylene and polyethylene, linear low-density polyethylene and aliphatic esters such as polylactic acid, microporous membranes, mesh materials, etc., and combinations thereof.

[0068] As an example, the body-side web 10 may be composed of a melt-bonded or spunbonded polyolefin web. Alternatively, the body-side web 10 may be a bonded, combed web composed of natural and / or synthetic fibers. The body-side web 10 may be composed of a substantially hydrophobic material, and the hydrophobic material may optionally be treated with a surfactant or otherwise treated to impart the desired level of wettability and hydrophilicity. The surfactant may be applied by any conventional method, such as spraying, printing, brushing, etc. The surfactant may be applied to the entire body-facing web 10, or it may be selectively applied to specific portions of the body-side web 10.

[0069] In some embodiments, the garment sidewall 11 and / or portions thereof may be breathable and / or liquid-impermeable. The garment sidewall 11 and / or portions thereof may further be elastic, stretchable, or non-stretchable. The garment sidewall 11 may be composed of a single layer, multiple layers, laminated materials, spunbond fabrics, membranes, meltblown fabrics, elastic meshes, microporous meshes, bonded carded meshes, or foams provided by elastic or polymeric materials. In some embodiments, for example, the garment sidewall 11 may be composed of a microporous polymer membrane such as polyethylene or polypropylene.

[0070] Despite Figure 2 The image is shown only as a single line. In some specific embodiments, the garment side mesh 11 can be a two-layer structure, comprising an outer layer material and an inner layer material, which can be bonded together, for example, by a laminating adhesive. Suitable laminating adhesives can be applied continuously or intermittently as beads, sprays, parallel vortices, etc., but it should be understood that the inner layer can be bonded to the outer layer by other adhesive methods, including but not limited to, ultrasonic bonding, thermal bonding, pressure bonding, etc.

[0071] The front elastic filament 12 and the rear elastic filament 13 can respectively form a portion of the front region 21 and the rear region 22 of the absorbent article formed at least partially by the elastic laminate 33. Although in Figure 2 While only shown as a single line, the front elastic filament 12 and the rear elastic filament 13 may comprise multiple elastic filaments to form wide elasticized regions on the front region 21 and the rear region 22 of the absorbent article 20. For example, the front elastic filament 12 may represent approximately 5 to approximately 30 individual elastic filaments spaced apart from each other to form the elasticized front region 21. Similarly, the rear elastic filament 13 may represent approximately 5 to approximately 30 individual elastic filaments spaced apart from each other to form the elasticized rear region 22. In various embodiments, the multiple elastic filaments represented by the front elastic filament 12 and the rear elastic filament 13 may be spaced apart on the front region 21 or the rear region 22 within a range of approximately 7 cm to approximately 25 cm.

[0072] The crotch elastic threads 14a and 14b may represent leg elastic threads. For example, the absorbent article 20, which is at least partially formed of the elastic laminate 33, may include a leg opening that is at least partially surrounded by the crotch elastic threads 14a and 14b. As will be described later, as part of the complete process of manufacturing the absorbent article 20, a portion of the elastic laminate 33 may be cut off to form the leg opening of the absorbent article that is at least partially formed of the elastic laminate 33.

[0073] In at least some embodiments, the crotch elastic threads 14a, 14b can be fed into the roller gap 32 at varying positions transverse to the machine direction MD to form an arcuate pattern of the crotch elastic threads 14a, 14b within the elastic laminate 33. This arcuate pattern can be formed by changing the position of a control lever or arm associated with each crotch elastic thread 14a, 14b. The arcuate pattern of the crotch elastic threads 14a, 14b can overlap with a region of the elastic laminate 33 that has been cut away to form a leg opening.

[0074] Another component of the elastic laminate 33 may include one or more adhesives to secure one or more crotch area elastic threads 14a, 14b within the elastic laminate 33. In some embodiments, an adhesive finish may be applied to one or more body-side webs 10 and garment-side webs 11, for example, via applicator heads 41 and / or 42. For example, applicator heads 41 and / or 42 may spray adhesive onto the inner surfaces of the body-side webs 10 and / or the garment-side webs 11, wherein the inner surfaces of the body-side webs 10 and the garment-side webs 11 are the surfaces that contact these elastic threads 12-14b.

[0075] It is feasible that the adhesive applied to the body-side web 10, the garment-side web 11, and / or these elastic yarns 12-14b can be applied continuously and intermittently to create adhesive regions with varying bond strengths within the elastic laminate 33. For example, in some embodiments, the finishing adhesive can be applied continuously to any one or both of the body-side web 10 and the garment-side web 11. In these embodiments, the adhesive can be applied intermittently to one or more of these elastic yarns 12-14b. In this way, weakly bonded areas 211 (where only the adhesive applied to the body-side web 10 and / or the garment-side web 11 is present) and strongly bonded areas 212 (where the adhesive is present on one or more of the body-side web 10, the garment-side web 11, and these elastic yarns 12-14b) can be formed in the elastic laminate 33.

[0076] In a further embodiment, the adhesive may be applied only to one of the body-side web 10 and / or the garment-side web 11 and one or more of the elastic yarns 12-14b. In such an embodiment, the amount of adhesive applied to the body-side web 10 and / or the garment-side web 11 or one or more of the elastic yarns 12-14b can vary. For example, the areal density of the adhesive applied along a first length to the body-side web 10 and / or the garment-side web 11 or one or more of the elastic yarns 12-14b may be less than the adhesive applied along a second portion to the body-side web 10 and / or the garment-side web 11 or one or more of the elastic yarns 12-14b. In this way, a weakly bonded area 211 and a strongly bonded area 212 can be created while applying adhesive only to one of the body-side web 10 and / or the garment-side web 11 and one or more of the elastic yarns 12-14b. In at least some of these embodiments, the amount of adhesive applied can be varied by continuous spraying to form weakly bonded areas 211 and strongly bonded areas 212. In other embodiments, a first adhesive coating can be applied continuously, while a second adhesive coating can be applied intermittently on top of the first adhesive coating to form weakly bonded areas 211 and strongly bonded areas 212.

[0077] After each component of the elastic laminate 33 is unfolded and adhesive is applied to one or more components, the components come together at the roll gap 32. The upper clamping roller 30 and the lower clamping roller 31 are positioned adjacent to each other to press them together as the body-side web 10, the garment-side web 11, and the elastic fibers 12-14b enter the roll gap 32. The pressure applied to the components of the elastic laminate 33 at the roll gap 32 helps to bond the components together to form a single elastic laminate 33. Figure 2 It can be seen that the elastic laminate 33 exits the roll gap 32.

[0078] In at least some embodiments, the elastic yarns 12-14b are fed into the roll gap 32 in a stretched state. For example, the elastic yarns 12-14b may be stretched to between about 120% and about 180% of their unstretched state before being fed into the roll gap 32. Since how these elastic yarns 12-14b adhere to the body-side web 10 and the garment-side web 11 is attributed to the adhesive applied to the body-side web 10, the garment-side web 11, and / or these elastic yarns 12-14b, when these elastic yarns 12-14b relax back to their unstretched state, these elastic yarns 12-14b may cause the absorbent core 24 positioned on these elastic yarns 12-14b to converge and / or the garment-side web 11 to wrinkle. The gathering of the absorbent core 24 can reduce the effectiveness of the absorbent product in retaining bodily excrement, and the wrinkles of the fabric side mesh 11 can reduce the visual appeal of the absorbent product by twisting the graphics printed on the fabric side mesh 11 or other parts of the absorbent product.

[0079] To reduce the gathering of the absorbent core 24 and / or the wrinkling of the fabric mesh 11 on the side of the garment, at least partially... Figure 1A The front weakening zone 21A, rear weakening zone 22A, first weakening zone 23A, and second weakening zone 23B of the crotch area weaken or cut these elastic filaments 12-14b to reduce the elasticity of specific areas of the absorbent article 20. It is known that such weakening or cutting is carried out, for example, via a weakening device, wherein the weakening roller in the weakening device may include a plurality of protrusions, such as cutters, which are respectively aligned with the front weakening zone 21A, rear weakening zone 22A, first weakening zone 23A, and second weakening zone 23B of the elastic laminate 33, such that when the elastic laminate 33 is fed to the weakening device, the plurality of protrusions are aligned with the plurality of elastic filaments 12-14b within these weakening zones.

[0080] like Figure 1A and 1B As shown, the front weakening region 21A and the rear weakening region 22A overlap with the weak bonding regions 211 and 221 of the elastic laminate 33. Therefore, the elastic fibers 12 and 13, which are at least partially weakened as they pass through the roll gap 33, are typically present in the weak bonding region 211. As previously mentioned, the amount of adhesive within the weak bonding region 211 may be insufficient to firmly hold these elastic fibers 12 and 13 in place after partial weakening. Therefore, after partial weakening, at least a portion of these elastic fibers 12 and 13 can elongate between the body-side web 10 and / or the clothing-side web 11 without pulling on the body-side web 10 and / or the clothing-side web 11, thereby reducing wrinkles in the body-side web 10 and / or the clothing-side web 11 and / or the subsequent gathering of the absorbent core 24 placed on the elastic laminate 33. In the same manner, the elastic threads 14a to 14b located in the first weakening zone 23A and the second weakening zone 23B of the crotch area are also weakened when the elastic composite 33 is sent to the weakening device.

[0081] The inventors of this application have discovered that when the cutter in the weakening device contacts and presses against the elastic fibers 12-14b, the flexural force of the elastic fibers 12-14b, for example, comprising urethane, can be between about 0.52 MPa and about 63.0 MPa, while the flexural force of the body-side web 10 and / or clothing-side web 11, for example, comprising polypropylene, can be between about 25 MPa and about 317 MPa. Since their flexural force ranges overlap, it becomes essential to achieve precise control of the contact pressure in each weakening zone to ensure that the weakening or cutting process does not affect the body-side web 10 and / or clothing-side web 11 to the point of cutting holes that severely affect the product's appearance, while also preventing situations where the weakening is inadequate or insufficient.

[0082] for Figure 1A and 1B For the absorbent article 20 shown, since the front elastic filament 12, the rear elastic filament 13, and the crotch elastic filaments 14a and 14b in the elastic laminate 33 are located in the front weakening region 21A, the rear weakening region 22A, and the first and second crotch weakening regions 23A-B, which are spaced apart from each other along the machine direction (MD direction), it is challenging to achieve substantially consistent contact pressure in these weakening regions 21A, 22A, and 23A-B during synchronous weakening by means of a single weakening device. This is because along the machine direction... The contact pressure of multiple weakening rollers arranged at intervals during high-speed rolling affects each other. For example, the contact pressure applied to the weakening roller at the middle position of the weakening roller shaft will inevitably be greater than the contact pressure applied to the weakening rollers on both sides of it. Furthermore, as the axial length of the weakening roller shaft increases, the position fluctuation or vibration of the weakening roller at the middle position also increases. Finally, considering that the adhesive thickness of different weakening zones may be inconsistent, it is difficult for a single weakening device to meet the contact pressure requirements of weakening zones with different thicknesses.

[0083] Based on the above understanding, unlike the method and system taught in, for example, CN104203177A, which uses a single weakening device to simultaneously produce an absorbent article 20 with a weakened elastic laminate 33, the system for producing an absorbent article 20 according to the present invention includes producing an absorbent article 20 with a weakened elastic laminate 33 by means of two weakening devices 60 and 70 arranged in succession to eliminate the deficiencies in the prior art.

[0084] like Figures 2 to 5As shown, the elastic laminate 33, formed by the lamination of the upper clamping roller 30 and the lower clamping roller 31, sequentially passes through the first weakening device 60 and the second weakening device 70 arranged in succession. This weakens or cuts the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarns 14a and 14b, which are located in different weakening zones along the machine direction (MD direction), at different processes or workstations within the elastic laminate 33. To ensure the product appearance of the absorbent material 20 after cutting in the front weakening zone 21A and the rear weakening zone 22A, the cutters of the first weakening device 60 and the second weakening device 70 arranged in succession preferably face the clothing side fiber mesh 11 of the elastic laminate 33.

[0085] Specifically, such as Figure 2 As shown, a slitting blade 34 is provided before the subsequent weakening or cutting process to slit the integral elastic laminate 33 into a front region 21, a rear region 22, and a crotch region 23 along the machine direction (MD direction). A first weakening device 60 and a second weakening device 70 are continuously provided downstream of the slitting blade 34 to weaken or cut the elastic wires 13 in the rear weakening region 21B of the rear region 22, the elastic wires 12 in the front weakening region 21A of the front region 21, and the elastic wires 14a and 14b in the first and second weakening regions 23A and 23B of the crotch region 23, respectively.

[0086] As a feasible approach, the rear region 22 of the elastic laminate 33, after being slit, travels along the machine direction (MD direction) through the first weakening device along the first path L1 and then moves above the second weakening device 70. The front region 21 and crotch region 23 of the elastic laminate 33, after being slit, travel along the machine direction (MD direction) above the first weakening device 60 and through the second weakening device 70 along the second path L2, where they are also weakened. The two travel paths eventually converge at the traction roller downstream of the second weakening device 70. This method of continuing to set two weakening devices 60 and 70 can significantly reduce the length of the weakening roller shafts in each weakening device 60 and 70 and avoid mutual influence or interference when applying contact pressure to different weakening areas. On the other hand, it can adaptively adjust the weakening devices according to factors such as the sizing thickness, required contact pressure, and materials of the elastic yarn and fiber web in different areas, resulting in relatively high adjustment flexibility.

[0087] like Figure 3A and 3BAs shown, a first weakening device 60 is illustrated, comprising a first weakening roller shaft 61 with only a first weakening roller 62, a first bottom roller 63 arranged in conjunction with the first weakening roller 62, and a first base 64. The first weakening roller shaft 61 is designed to rotate about the first weakening roller axis A1 under the drive of an external drive mechanism (not shown), and the first bottom roller 63 is designed to rotate about the first bottom roller axis A2. One side of the first weakening roller shaft 61 has a first upper drive wheel 61A, and the first bottom roller 63 has a first lower drive wheel 63A on one side that meshes with the first upper drive wheel 61A. As a result, in response to the rotation of the first weakening roller shaft 61, the first bottom roller 63 also rotates synchronously. Here, both the first weakening roller shaft 61 with the first weakening roller 62 and the first bottom roller 63 are rotatably mounted on the first base 64. Furthermore, a first adjustment mechanism 65 is provided above the first base 64 and is operatively connected to the first weakening roller shaft 61. This mechanism is used to move the first weakening roller shaft 61 vertically upwards or downwards in response to an operator's signal, thereby adaptively adjusting the gap between the first weakening roller 62 and the paired first bottom roller 63 on the first weakening roller shaft 61, allowing the elastic laminate 33 to pass through, according to factors such as the thickness of the elastic laminate 33 supplied to the first weakening device 60. It is feasible that the first adjustment mechanism can be an electric motor or a hydraulic motor.

[0088] like Figure 3A and 3B As shown in detail, the first weakening roller 62 has a preferably removable first cutter 62A on its outer circumference, wherein the first cutter 62A is, for example, in Figure 4A The diagram shows a plurality of generally radially outwardly protruding protrusions arranged in a predetermined pattern. Since the first cutter 62A with the predetermined pattern is arranged only at the center of its circumference in the first weakening roller 62, areas without protrusions (areas without weakening function) are formed on both sides of the first cutter 62A. The adjacent areas without protrusions and the first cutter 62A are arranged along axis A1 such that the areas without protrusions mate with the strong adhesion region 222 of the elastic laminate 33 fed between the first weakening roller 62 and its mating first bottom roller 63, and the first cutter 62A with the predetermined pattern protrusions aligns with the elastic filaments 13 located within the weak adhesion region 221. Typically, the specific arrangement of the protrusions in the first cutter 62A on the surface of the first weakening roller 62 can be determined based on which specific elastic filaments 13 will be weakened.

[0089] For example, the first cutter 62A may include four rows of protrusions aligned with four elastic filaments 13 in the rear region 22 of the elastic laminate 33. However, it should be understood that the scope of this disclosure is not limited to the specific number of protrusions depicted herein. For example, the first weakening roller 62 contemplated in this disclosure may have about 5 to about 30 rows of protrusions, which may correspond to a suitable number of elastic filaments 13 in the rear region 22 of the elastic laminate 33.

[0090] Preferably, for example, Figure 4A As shown, the protrusions are depicted as having a generally flat top surface, but other protrusion shapes are equally suitable for at least partially weakening the elastic filament 13. Furthermore, although each column of protrusions is staggered relative to adjacent columns, this is not required in all embodiments. In other embodiments, each protrusion in a column may be aligned with protrusions in an adjacent column.

[0091] More preferably, the protrusion may have a generally rectangular or pyramidal shape, as it may taper gradually as it extends away from the first weakening roller 62. In different embodiments, the protrusion may extend away from the first weakening roller 62 by between approximately 1.50 mm and approximately 4.0 mm. Additionally, the protrusion may have a width between approximately 6.0 mm and approximately 102 mm at the farthest surface of the first weakening roller 62. Therefore, the protrusion may have corners with an angle between approximately 90 degrees and approximately 120 degrees. Furthermore, although the corners are generally relatively sharp, in some alternative embodiments, the corners may be beveled, chamfered, rounded, etc.

[0092] Alternatively, the protrusion may have a circular surface furthest from the first weakening roller 62, opposite the flat distal surface of the protrusion. In various feasible embodiments, the protrusion may extend from the first weakening roller 62 by a first length plus a second length. At the junction, the first length may be the length by which the protrusion extends away from the first weakening roller 62 before it begins to bend toward the tip. The second length may be the length by which the protrusion extends away from the first weakening roller 62 between the tip and the junction. The first length may be between about 0.7 mm and about 2 mm. The second length may be between about 0.76 mm and about 2 mm. The width may represent the width of the protrusion between two opposing junctions. An angle may be formed by an imaginary line extending between the tip and one of the junctions. The width may be between about 1.5 mm and about 3 mm. The angle may be between about 10 degrees and about 50 degrees. In some embodiments, the distal portion of the protrusion may be hemispherical. In such an embodiment, angle 142 may be 45 degrees, and width 145 may represent the diameter of the distal portion of the protrusion.

[0093] With this design, when the protrusions contact the elastic wire 13, they can compress the elastic wire 13 at a pressure between approximately 16 psi (0.11 MPa) and approximately 5800 psi (40 MPa). In any case, the contact pressure applied by the protrusions of the weakening device causes the elastic wire 13 to become partially weakened. It has been found that when using protrusions with the shape of the present invention, these pressures are sufficient to partially weaken the elastic wire 13 without completely severing it.

[0094] Additionally, it may be desirable to partially weaken one or more portions of the plurality of elastic filaments 13 in the weakening device without affecting the body-side web 10 and / or the clothing-side web 11. For example, some embodiments may partially weaken the elastic filaments 13 without cutting through or otherwise forming holes or cavities in the body-side web 10 and / or the clothing-side web 11. In such embodiments, the amount of pressure applied by the protrusions may be greater than the flexural force of one or more elastic filaments, but less than the flexural force of the body-side web 10 and / or the clothing-side web 11.

[0095] In feasible embodiments, when the plurality of elastic filaments 13 comprise urethane, the flexural strength of the plurality of elastic filaments 13 to be partially weakened may be between about 0.52 MPa and about 63.0 MPa, while when the body-side web 10 and / or the clothing-side web 11 comprise polypropylene, the flexural strength of the body-side web 10 and / or the clothing-side web 11 may be between about 25 MPa and about 317 MPa. Of course, although these ranges overlap, in such embodiments, a particular elastic filament 13 may be selected to have a lower flexural strength than a particular selected body-side web 10 and / or clothing-side web 11 to ensure that the weakening process does not affect the body-side web 10 and / or clothing-side web 11.

[0096] In other feasible embodiments, additional forms of energy may be applied during the weakening step. For example, in addition to applying pressure to the elastic wire 13, the protrusion may also be heated. Thus, the heat from the protrusion may further contribute to the partial weakening of the elastic wire 13. In some embodiments, the protrusion may be heated to between about 45°C and about 150°C. In at least some embodiments where the protrusion is heated, the protrusion may compress the elastic wire 13 to a lesser extent than in embodiments where the protrusion is not heated but still results in partial weakening of the elastic wire 13. For example, in embodiments where the protrusion is heated, the protrusion may be configured to apply a pressure between about 25 psi (0.17 MPa) and about 1,500 psi (10.0 MPa) to the elastic wire 13.

[0097] As can be seen from the above, the first weakening device 60 of this disclosure effectively shortens the length of the first weakening roller 61 and suppresses the vibration of the first cutter 62A during high-speed operation, thereby reducing the weakening or cutting damage area of ​​the supplied elastic laminate 33 and helping to improve the appearance quality. The use of a slender and miniaturized first weakening roller 62 allows for precise cutting at any position within the required cutting area, offering high flexibility. Furthermore, the use of a slender and miniaturized first weakening roller 62 enables small-scale cutting of the fabric web 11 on the garment side, ensuring that only a small area of ​​shallow markings remain without any cuts, significantly improving the aesthetics of the product.

[0098] Furthermore, such as Figures 4A to 4C As shown, a second weakening device 70 is illustrated, comprising a second weakening roller shaft 71 with a second weakening roller 72, a second bottom roller 73 arranged in conjunction with the second weakening roller 72, and a second base 74. The second weakening roller shaft 71 is designed to rotate about a second weakening roller axis A3 under the drive of an external drive mechanism (not shown), and the second bottom roller 73 is designed to rotate about a second bottom roller axis A4. One side of the second weakening roller shaft 71 has a second upper drive wheel 71A, and the second bottom roller 73 has a second lower drive wheel 73A on one side that meshes with the second upper drive wheel 71A. As a result, in response to the rotation of the second weakening roller shaft 71, the second bottom roller 73 also rotates synchronously. Here, both the second weakening roller shaft 71 with the second weakening roller 72 and the second bottom roller 73 are rotatably mounted on the second base 74.

[0099] Furthermore, a second adjustment mechanism 75 is provided above the second base 74 and is operatively connected to the second weakening roller shaft 71. This mechanism is used to move the second weakening roller shaft 71 vertically upwards or downwards in response to an operator's signal, thereby adaptively adjusting the gap between the second weakening roller 72 and the paired second bottom roller 73 on the second weakening roller shaft 71, allowing the elastic laminate 33 to pass through, according to factors such as the thickness of the elastic laminate 33 supplied to the second weakening device 70. It is feasible that the second adjustment mechanism 75 can be an electric motor or a hydraulic motor.

[0100] like Figure 5 As shown in the most detailed example, the second weakening roller 72 has a preferably detachable second cutter 72A and a third cutter 72B on its outer circumference, wherein the second cutter 72A and the third cutter 72B are, for example, on... Figure 4AThe diagram shows multiple radially outward protrusions arranged in a predetermined pattern. Based on this design, the second weakening roller 72 is divided along its circumference into a region without protrusions (a region without weakening function) located in the middle and a second cutter 72A and a third cutter 72B with predetermined patterns arranged on both sides. As a result, the second cutter 72A, the region without protrusions, and the third cutter 72B arranged sequentially from right to left along axis A3 are designed such that the region without protrusions is paired with the strong bonding area 212 of the elastic laminate 33 fed between the second weakening roller 72 and the mating second bottom roller 73, and the second cutter 72A with predetermined pattern protrusions is aligned with the elastic threads 14a and 14b in the first weakening area 23A and the second weakening area 23B of the crotch area, which are aligned along the machine direction (MD direction), and the third cutter 72B with predetermined pattern protrusions is aligned with the front area elastic thread 12 in the front area 21. Typically, the specific arrangement of the protrusions in the second cutter 72A and the third cutter 72B on the surface of the second weakening roller 72 can be determined based on which specific elastic wires 12 or 14a-b will be weakened.

[0101] For example, the second cutter 72A may include three rows of protrusions aligned with three elastic filaments 14a and 14b within the first weakened region 23A and the second weakened region 23B of the crotch area of ​​the elastic laminate 33. In contrast, the third cutter 72B may include six rows of protrusions aligned with six front region elastic filaments 12 within the front region 21 of the elastic laminate 33. However, it should be understood that the scope of this disclosure is not limited to the specific number of protrusions depicted herein. For example, the third cutter 72B contemplated in this disclosure may have approximately 10 to approximately 30 rows of protrusions, which may correspond to a suitable number of elastic filaments 12 in the front region 21 of the elastic laminate 33.

[0102] The possible shapes of the protrusions are the same as and interchangeable with the protrusions in the first weakening device 60 described above, and will not be repeated here.

[0103] Similarly, as can be seen from the above, the second weakening device 70 of this disclosure effectively shortens the length of the second weakening roller 71 and suppresses the vibration of the second cutter 72A and the third cutter 72B during high-speed operation, thereby reducing the weakening or cutting damage area of ​​the supplied elastic laminate 33 and helping to improve the appearance quality. The use of a slender and miniaturized second weakening roller 71 allows for precise cutting at any position within the required cutting area, offering high flexibility. Furthermore, the use of a slender and miniaturized second weakening roller 71 enables small-scale cutting of the fabric web 11 on the garment side, ensuring that only a small area of ​​shallow markings remain without any cuts, significantly improving the aesthetics of the product.

[0104] Next, referring to the manufacturing system shown in Figures 1 to 5, we will describe the weakened elastic laminate 33 for the three-piece absorbent article 20 described above. This invention proposes a method for manufacturing the weakened elastic laminate 33 of the absorbent article, including a feeding process, a sizing process, a laminating process, and a weakening process, specifically as follows... Figure 2 As shown.

[0105] Supply process: The stretchable front elastic yarn 12, rear elastic yarn 13, and crotch elastic yarn 14a-b are arranged between the garment-side fiber web 11 and the body-side fiber web 10. The supply process of the garment-side fiber web 11 and the body-side fiber web 10 may include a traction roller and a guide roller (not shown). The traction roller guides the garment-side fiber web 11 and the body-side fiber web 10 to travel along a designated path under appropriate tension, while the elastic yarns are fed between the garment-side fiber web 11 and the body-side fiber web 10 under appropriate tension guided by the guide roller.

[0106] Adhesive application process: Multiple adhesive application heads 41 to 46 are set on the processing paths of the front elastic yarn 12, the rear elastic yarn 13 and the crotch elastic yarn 14a-b to apply adhesive to the front elastic yarn 12, the rear elastic yarn 13 and the crotch elastic yarn 14a-b respectively.

[0107] Specifically, these applicator heads 41 to 46 apply adhesive in a continuous or intermittent manner to the outer periphery of the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarn 14a-b along the flow direction, forming a strong bonding area 212 and a weak bonding area 211 in the front region 21, and a strong bonding area 222 and a weak bonding area 221 in the rear region 22, respectively. The strong bonding areas 212 and 222 in the front and rear regions avoid the front weakening areas 21A and 22A, respectively, reducing the application cost to some extent. By controlling the application weight of the applicator heads 41 to 46, the peel strength between the elastic yarn and the fabric side web 11 and the body side web 10 can be adjusted.

[0108] Lamination process: After adhesive application, the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarn 14a-b are laminated with the clothing-side fiber web 11 and the body-side fiber web 10 respectively at the upper clamping roller 30 and the lower clamping roller 31 to form an elastic laminate 33. Specifically, these weak adhesion areas 211 and 221 and strong adhesion areas 221 and 222 are alternately staggered in the transverse or CD direction of the absorbent product 20. The upper clamping roller 30 and the lower clamping roller 31 clamp and drive the elastic laminate 33, increasing the adhesion between the adhesives while driving the elastic laminate 33 and adjusting its running speed.

[0109] Weakening process: such as Figure 2As shown, the elastic laminate 33, formed by the lamination of the upper clamping roller 30 and the lower clamping roller 31, is successively passed through the first weakening device 60 and the second weakening device 70, thereby weakening the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarn 14a-b in the elastic laminate 33 in the front weakening zone 21A, the rear weakening zone 22A, and the first and second weakening zones 23A and 23B in the crotch area, respectively. Preferably, in order to ensure the aesthetics of the weakening of the garment side fiber web 11 in the front weakening zone 21A and the rear weakening zone 22A, the cutter in the first weakening device 60 and the second weakening device 70 faces the side of the garment side fiber web 11 of the elastic laminate 33.

[0110] like Figure 2 As shown, a slitting blade 34 is provided before the weakening process to cut the integral elastic laminate 33 into a rear region 22, a front region 21, and a crotch region 23. Two first weakening devices 60 and a second weakening device 70 are continuously arranged on the downstream side of the slitting blade 34 to weaken the rear weakening region 22A in the rear region 22 and the front weakening region 21A in the front region 21 and the first and second weakening regions 23A and 23B in the crotch region 23, respectively. More specifically, the rear region 22 of the elastic laminate 33, after being cut, is weakened along a first path L1 by the first weakening device and then moves above the second weakening device 70. The front region 21 and the crotch region 23 of the elastic laminate 33, after being cut, move above the first weakening device 60 and through the second weakening device 70 along a second path L2 and are weakened. The two travel paths L1 and L2 eventually merge at the traction rollers on the downstream side of the first weakening device 60 and the second weakening device 70. This arrangement of two first weakening devices 60 and two weakening devices 70 allows for individual adjustment of the weakening devices corresponding to the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarns 14a-b, providing relatively high flexibility in adjustment.

[0111] After being weakened, the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarn 14a-b will not adhere to the garment side mesh 11 and the body side mesh 10 in the front weakened area 21A and the rear weakened area 22A because no adhesive has been applied. Therefore, after being weakened by the first weakening device 60 and the second weakening device 70, the front elastic yarn 12, the rear elastic yarn 13, and the crotch elastic yarn 14a-b will not adhere to the garment side mesh 11 and the body side mesh 10 in the front weakened area 21A, the rear weakened area 22A, and the crotch area 21A and the rear weakened area 22A. The weakened area loses its elasticity and quickly rebounds, thus meeting the weakening requirements of the elastic laminate 33 of the absorbent product 20, ensuring the weakening effect, improving the flatness of the product, and weakening is performed on the body side fiber mesh 10 side, so that the body side fiber mesh 10 is cut through but the clothing side fiber mesh 11 is not cut through, ensuring that the clothing side fiber mesh 11 only leaves a mark consistent with the cutter of the first weakening device 60 and the second weakening device 70, without any cuts, greatly improving the aesthetics of the product.

[0112] According to the inventors' tests and actual machine operation results, compared with the prior art, the system and method for manufacturing absorbent articles with weakened elastic laminates significantly achieve miniaturization of the weakening device and shortening of the roller, reducing its length by at least 40% to 60% of that in the prior art. Therefore, under a contact pressure of, for example, 6 bar, the maximum vibration of the cutter in this invention is no higher than 0.0066 mm, approximately one-third of that in the prior art, compared to the maximum vibration of approximately 0.01697 mm for the cutter.

[0113] Furthermore, by optimizing the pattern and width of the weakening roller, an even better product aesthetic can be achieved.

[0114] It should also be noted that, although the above embodiments are all for a three-piece absorbent article 20, the method for weakening the elastic laminate of the absorbent article provided by the present invention is not only applicable to... Figure 1A The three-piece absorbent article 20 shown in Figure B can also be used in a two-piece absorbent article 20.

[0115] Hereinafter, embodiments of the present invention have been illustrated and described, but those skilled in the art should understand that various modifications, omissions, and additions can be made without departing from the spirit and scope of the invention. It should not be understood as limited to the specific embodiments described herein, but encompasses all possible embodiments embodied within the scope and equivalents of the features described in the appended claims.

[0116] The dimensions and values ​​disclosed herein should not be construed as strictly limited to the precise numerical values ​​stated. Rather, unless otherwise specified, each such dimension is intended to represent the value and a range of functionally equivalent values ​​around that value. For example, a dimension disclosed as “40 mm” is intended to represent “approximately 40 mm”.

[0117] All documents referenced in the “Detailed Description” section are incorporated herein by reference in the relevant sections; any reference to any document should not be construed as an admission that it is prior art concerning the invention. In the event of any conflict between the meaning or definition of any term in this written document and any meaning or definition of a term in the incorporated documents, the meaning or definition assigned to the term in this written document shall prevail.

[0118] While specific embodiments of the invention have been shown and described, it will be apparent to those skilled in the art that many other changes and modifications can be made without departing from the spirit and scope of the invention. Therefore, the appended claims are intended to cover all such changes and modifications within the scope of the invention.

[0119] When describing elements of the present invention or preferred embodiments thereof, the articles “a,” “an,” “the,” and “the” are intended to indicate the presence of at least one element. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that additional elements may be present in addition to those listed. Many modifications and variations can be made to the invention without departing from its spirit and scope. Therefore, the above embodiments are not intended to limit the scope of the invention.

Claims

1. A method for weakening the elastic laminate of an absorbent article, the method comprising: The fabric side mesh and the body side mesh are moved forward along the machine direction; This allows multiple elastic wires to move forward along the machine direction while under tension. Adhesive is continuously applied to a first portion of the garment side mesh, the body side mesh, and at least one of the multiple elastic filaments to form a strong adhesive area; Adhesive is intermittently applied to a second portion of the garment-side web, the body-side web, and at least one of the multiple elastic filaments to form a weak bonding area, wherein the adhesive surface density of the weak bonding area is less than that of the strong bonding area. The multiple elastic threads are sandwiched between the fabric side mesh and the body side mesh; The fabric side mesh, body side mesh, and multiple elastic fibers are laminated to form an elastic composite. The elastic laminate is divided into a first part that moves along a first path in the machine direction and a second part that moves along a second path in the machine direction; as well as The first weakening device arranged in the first path weakens multiple elastic filaments in the weak bonding area of ​​the first part of the elastic laminate, and the second weakening device arranged in the second path weakens multiple elastic filaments in the weak bonding area of ​​the second part of the elastic laminate.

2. The method according to claim 1, wherein weakening the plurality of elastic wires includes cutting at least one or all of the plurality of elastic wires.

3. The method of claim 1, wherein weakening the plurality of elastic wires comprises applying a contact pressure of at least 2.5 bar to the elastic wires without completely severing them.

4. The method according to any one of claims 1 to 3, wherein at least one or all of the plurality of elastic wires are weakened by means of a cutter in the first weakening device and the second weakening device, wherein the jitter of the cutter is not higher than 0.006 mm when the contact pressure is not less than 5 bar.

5. The method according to any one of claims 1 to 3, wherein the absorbent article comprises a front region, a rear region, and a crotch region arranged in a transverse direction, wherein the first portion is the rear region of the absorbent article and the second portion is the front region and crotch region of the absorbent article.

6. The method of claim 5, wherein the first and second portions of the elastic laminate are weakened without cutting either the garment-side web or the body-side web.

7. A weakening device for the method of any one of claims 1 to 6, comprising: A first weakening roller shaft having a first weakening roller axis; A first bottom roll arranged in pair with the first weakening roll, on the axis of the first bottom roll; as well as A first cutter located on the outer circumference of a first weakening roller, wherein the first cutter includes a protrusion with a predetermined pattern located in the middle; and regions without protrusions located on both sides of the first cutter, wherein the first cutter is aligned with the weak bonding area of ​​the first portion of the elastic laminate along the machine direction, and the regions without protrusions are aligned with the strong bonding area of ​​the first portion of the elastic laminate along the machine direction.

8. A weakening device for the method of any one of claims 1 to 6, comprising: A second weakening roller shaft having a second weakening roller axis; A second bottom roll arranged in pair with the second weakening roll, on the axis of the second bottom roll; as well as A second cutter and a third cutter are located on the outer circumference of the second weakening roller, wherein both the second cutter and the third cutter include protrusions with a predetermined pattern. The second weakening roller is divided along its axial direction into a region without protrusions in the middle position and the second cutter and the third cutter on both sides thereon. The second cutter and the third cutter are aligned with the weak bonding area of ​​the second part of the elastic laminate along the machine direction, and the region without protrusions is aligned with the strong bonding area of ​​the second part of the elastic laminate along the machine direction.

9. The weakening device as described in claim 7 or 8, wherein, The protrusion is designed to have a generally flat top surface, or a generally rectangular or pyramidal shape, or a circular surface furthest from the weakening roller.

10. An absorbent article comprising a front area, a rear area, a crotch area, and an absorbent core, wherein the front area, the rear area, and the crotch area are all elastic laminates formed by laminating a garment side mesh, a body side mesh, and multiple elastic fibers. The front area, rear area and crotch area are weakened by the method of any one of claims 1 to 6.

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