Preparation method of pull-ups with organ waistline

Abstract

The invention relates to the field of hygienic products, in particular to a preparation method of pull-ups with an organ waistline. Comprising the following steps: S1, prefabricating an organ waistline assembly; S11, selecting a non-woven fabric base material layer; and S12, preparing an elastic material layer: clamping a continuous zigzag or sine wave-shaped path of the elastic material layer between the two non-woven base material layers, or compounding the elastic material layer on the single-side surface of the single-layer non-woven base material layer through dispensing to form a three-dimensional wrinkle structure. The technical problems that when existing pull-ups are used, the waistline stress is uneven, the comfort of attaching to the skin of an infant is poor, and the stability is poor are solved. By arranging the elastic material layer with a specific path (zigzag or sine wave shape) and a specific angle, the organ waistline assembly with a three-dimensional fold structure is formed, and high elasticity, high resilience and comfortable fitting are achieved.

Description

Technical Field

[0001] This invention relates to the field of hygiene products, and more particularly to a method for preparing pull-up trousers with an accordion waistband. Background Technology

[0002] Pull-up diapers, as an important category of disposable hygiene products, are widely used by infants, young children, and adults with incontinence. The comfort, fit, and elasticity of their waistband structure directly determine the user experience. With the upgrading of consumer demands, users' core requirements for pull-up diapers have gradually shifted from basic leak prevention and moisture absorption functions to a "lightweight, highly fitted, and unrestricted" wearing experience.

[0003] Meanwhile, in existing manufacturing processes, the lamination of elastic materials with nonwoven fabric substrates often adopts full-width adhesive coating or linear continuous lamination methods, which not only increases the amount of adhesive used and raises production costs, but may also lead to a decrease in waistband breathability due to uneven adhesive distribution. In addition, the lack of targeted pretreatment processes for elastic materials before lamination can easily lead to uneven shrinkage and low waistband forming accuracy after lamination, further affecting the wearing experience and production qualification rate of the product.

[0004] Chinese Patent No. CN202322298775.9 discloses an adjustable tightness pull-up diaper, the structure of which includes a diaper body with Velcro fasteners on both sides of the upper end of the diaper body. Several breathable grooves are provided between the surface non-woven fabric and the bottom fabric of the diaper body. This patent allows adjustment of the tightness of the elastic waistband and the front elastic waistband through the Velcro. Furthermore, the three-dimensional pleated embossing and several breathable grooves reduce the obstruction of the absorbent core layer, allowing for better breathability. This enables moisture and heat inside the diaper body to be discharged promptly through the surface non-woven fabric and the bottom fabric below the breathable grooves. However, because the structural design only changes the tightness of the pull-up diaper from the surface, it cannot fundamentally achieve uniform stretching force, meet the requirements for a stable fit during infants' dynamic activities, and suffer from insufficient pleat unfolding during stretching and irreversible deformation after repeated stretching, resulting in poor durability of the waistband. Summary of the Invention

[0005] Therefore, in view of the above problems, the present invention proposes a method for preparing pull-up diapers with accordion waistbands, which solves the technical problems of uneven waistband force, poor comfort and stability when using existing pull-up diapers.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a method for preparing pull-up pants with an accordion waistband, comprising the following preparation steps: S1, Prefabricated accordion waistband assembly: S11. Select a nonwoven fabric substrate layer; S12, Preparation of the elastic material layer: A continuous zigzag or sinusoidal path of the elastic material layer is sandwiched between two layers of nonwoven fabric substrate, or it is bonded to one side of a single layer of nonwoven fabric substrate by dispensing adhesive to form a three-dimensional pleated structure. The three-dimensional pleated structure includes a non-closed angled connecting part, a longitudinal connecting part located between two adjacent connecting parts, and a connecting part for connecting the end of the connecting part to the end of the nonwoven fabric substrate layer. The maximum opening angle of the connecting part is 120°-150°, the length of the longitudinal connecting part is 5-8mm, and the width of the connecting part is 2-3mm. The angle between the zigzag or sinusoidal path of the elastic material layer and the length direction of the pull-up pants is 30°-60°. S13. Reinforcing zones are formed at both ends of the nonwoven fabric substrate layer and the elastic material layer by means of hot pressing, adhesive bonding or ultrasonic welding. S2, Pull-up diaper body molding: S21. The impermeable bottom layer is transported longitudinally along the production line; S22. Rotate the cut absorbent cores 90° and lay them at equal intervals on the impermeable bottom layer; S23. Assemble the accordion waistband assembly prefabricated in step S1 onto the front waist area and / or back waist area of ​​the pull-up pants, and fix it together with the liquid-impermeable bottom layer and the end of the absorbent core. S24. Cover the absorbent core and the accordion waist assembly with the liquid-permeable surface layer and fix them together as one piece; S25. The leg opening is formed by arc cutting, then folded longitudinally, sealed on the side and cut into individual finished products.

[0007] Furthermore, in step S1, the three-dimensional pleated structure is in a compressed and folded state in its natural state, with a folding compression rate of 40%-60%. When stretched to its maximum length, the pleats are fully unfolded without irreversible deformation, ensuring that the accordion waistband maintains a compact structure when not in use, which facilitates automated assembly, packaging, and transportation. Moreover, during the wearing and stretching process, the pleats can be smoothly and completely unfolded, providing ample stretching space to fit infants and young children of different body types.

[0008] Furthermore, in step S12, the dispensing is done using intermittent dot matrix dispensing with a dot spacing of 3-5 mm, which helps to reduce internal stress accumulation during stretching and prevent wrinkles, tears, or delamination.

[0009] Furthermore, in step S11, the nonwoven fabric substrate layer is a bicomponent spunbond thermally rolled nonwoven fabric.

[0010] Furthermore, in step S12, the elastic material layer is spandex yarn with a denier of 300-500D, which ensures sufficient resilience and tensile strength while also taking into account the fineness and uniformity of the material distribution.

[0011] Furthermore, in step S12, the elastic material layer undergoes a pre-stretching-static-low-temperature setting composite pretreatment process before configuration: first, it is stretched at 1.3-1.4 times the pre-stretching rate, and then left to stand for 7-9 minutes; then, it undergoes low-temperature setting at a temperature of 42-48℃ for 3.5-4.5 minutes; after setting, it is naturally cooled to room temperature before being composited to avoid wrinkle disorder or uneven wrinkling caused by shrinkage, ensuring consistent wrinkle structure formation, long-lasting and stable elasticity, and improved product yield.

[0012] Furthermore, in step S12, the zigzag path angle of the elastic material layer varies with the waist area, with the front waist angle being 45° and the back waist angle being 60°. Since the front waist angle is smaller, it provides denser pleats and stronger lateral binding force, which helps to fit the abdominal curve and prevent front leakage; the back waist angle is larger, the pleats unfold more gently, and the extensibility is better, which can accommodate the large stretching when the hips move and reduce marks.

[0013] Furthermore, in step S13, the welding pattern of the reinforcing zone is a continuous wavy shape, and the width of the reinforcing zone is 8-12mm.

[0014] By adopting the aforementioned technical solution, the beneficial effects of the present invention are: This invention forms a standardized three-dimensional pleated structure by arranging elastic material layers in a continuous zigzag or sinusoidal path and setting connecting parts, longitudinal connecting parts, and joints at specific angles. Simultaneously, the difference in the angle between the elastic material paths in the front waist area (45°) and the back waist area (60°) ensures more even stress distribution during stretching, allowing for a close fit to the curve of the human waist, effectively avoiding localized pressure and marks, while also improving the stability of the fit during dynamic activities and reducing the risk of slippage. This structural design creates an accordion waistband assembly with a three-dimensional pleated structure, achieving high elasticity, high resilience, and a comfortable fit.

[0015] The pre-stretching-static-low temperature setting process significantly improves the stability of elastic materials and avoids relaxation failure during use; The differentiated angles between the front and back waist areas conform to the ergonomic curves, enhancing the wearing experience; at the same time, the reinforced area effectively improves the connection strength at the end of the components, preventing delamination or breakage. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a structural schematic diagram of the accordion waistband assembly of the present invention; In the diagram: Front waist area-1, back waist area-2, crotch area-3, leg opening-4, accordion waistband assembly-5, non-woven fabric substrate layer-51, elastic material layer-52, reinforcement area-53, connecting part-54, longitudinal connecting part-55, joint part-56. Detailed Implementation

[0017] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. Example 1

[0018] refer to Figures 1-2 This embodiment provides a method for preparing pull-up pants with an accordion waistband, including the following preparation steps: S1, Prefabricated accordion waistband assembly: S11. Select nonwoven fabric substrate layer 51; S12, Preparation of elastic material layer 52: The continuous zigzag or sinusoidal path of the elastic material layer 52 is sandwiched between two nonwoven fabric substrate layers 51, or is bonded to one side of a single nonwoven fabric substrate layer 51 by dispensing adhesive to form a three-dimensional pleated structure. The three-dimensional pleated structure includes a non-closed angled connecting part 54, a longitudinal connecting part 55 located between two adjacent connecting parts 54, and a connecting part 55 for connecting the end of the connecting part 54 to the end of the nonwoven fabric substrate layer 51. The maximum opening angle of the connecting part 54 is 120°-150°, the length of the longitudinal connecting part 55 is 5-8mm, and the width of the connecting part 55 is 2-3mm. The zigzag or sinusoidal path of the elastic material layer 52 forms an angle of 30° to 60° with the length direction of the pull-up pants; S13. Reinforcing zones 53 are formed at both ends of the nonwoven fabric substrate layer 51 and the elastic material layer 52 by hot pressing, adhesive bonding or ultrasonic welding. S2, Pull-up diaper body molding: S21. The impermeable bottom layer is transported longitudinally along the production line; S22. Rotate the cut absorbent cores 90° and lay them at equal intervals on the impermeable bottom layer; S23. Assemble the prefabricated accordion waistband assembly from step S1 onto the front and / or back waist areas of the pull-up pants, and fix it together with the impermeable bottom layer and the end of the absorbent core. S24. Cover the absorbent core and the bellows waist assembly with the liquid-permeable surface layer and fix them together as one piece; S25. The leg opening is formed by arc cutting, then folded longitudinally, sealed on the side and cut into individual finished products.

[0019] Specifically, a pull-up trousers with an accordion waistband includes a front waist area 1, a back waist area 2, a crotch area 3, and two leg openings 4. The front waist area 1 and / or the back waist area 2 are provided with an accordion waistband assembly 5.

[0020] In step S1, the three-dimensional pleated structure is compressed and folded in its natural state, with a compression rate of 40%-60%. When stretched to its maximum length, the pleats are fully unfolded without irreversible deformation, ensuring that the accordion waistband maintains a compact structure when not in use, which facilitates automated assembly, packaging and transportation. Furthermore, during the wearing and stretching process, the pleats can be smoothly and completely unfolded, providing ample stretching space to fit infants and toddlers of different body types.

[0021] In step S12, intermittent dot matrix dispensing is used, with a dot spacing of 3-5mm. This helps to reduce the accumulation of internal stress during stretching and prevent wrinkles, tears, or delamination.

[0022] In step S11, the nonwoven substrate layer 51 is a bicomponent spunbond thermally rolled nonwoven fabric.

[0023] In step S12, the elastic material layer 52 is made of spandex yarn with a denier of 300-500D, which ensures sufficient resilience and tensile strength while also taking into account the fineness and uniformity of the material distribution.

[0024] In step S12, the elastic material layer 52 undergoes a pre-stretching-static-low temperature setting composite pretreatment process before configuration: first, it is stretched at 1.3-1.4 times the pre-stretching rate, and then left to stand for 7-9 minutes; then, it undergoes low temperature setting at 42-48℃ for 3.5-4.5 minutes; after setting, it is naturally cooled to room temperature before being composited to avoid wrinkle disorder or uneven wrinkling caused by shrinkage, ensuring consistent wrinkle structure formation, long-lasting and stable elasticity, and improved product yield.

[0025] In step S12, the zigzag path angle of the elastic material layer 52 varies with the waist area, with a 45° angle in the front waist area and a 60° angle in the back waist area. Because the angle in the front waist area is smaller, it provides denser pleats and stronger lateral binding force, which helps to fit the abdominal curve and prevent front leakage; the angle in the back waist area is larger, the pleats unfold more gently, and the elasticity is better, which can accommodate the large stretching when the hips move and reduce marks.

[0026] In step S13, the welding pattern of the reinforcing zone 53 is a continuous wave shape, and the width of the reinforcing zone 53 is 8-12mm.

[0027] In this embodiment, the wearing comfort and fit are improved through the design of various structures, the selection of materials, and the optimization of the manufacturing process. Example 2

[0028] Compared with Example 1, in this example, in step S12, the elastic material layer 52 adopts a sinusoidal wave composite with a wavelength of 12mm, an amplitude of 8mm, and an angle of 50° with the length direction of the pull-up pants; the folding compression rate is controlled at 50%. The three-dimensional pleated structure is sandwiched between two layers of non-woven fabric substrate 51 by hot pressing to form a sandwich structure, which improves the overall structural strength and appearance.

[0029] The welding method in reinforced area 53 is replaced with hot melt adhesive composite, and the adhesive type is PUR hot melt adhesive; the nonwoven fabric substrate layer 51 is replaced with ES composite fiber hot air nonwoven fabric to further improve softness.

[0030] Other technical solutions are the same as in Embodiment 1.

[0031] It should also be noted that in this invention, the included angle of the connecting part 54 is 120°-150°, the length of the longitudinal connecting part 55 is 5-8mm, the width of the connecting part 55 is 2-3mm, and the included angle between the zigzag or sinusoidal path of the elastic material layer 52 and the length direction of the pull-up pants is 30° to 60°. The specific parameters can be selected and applied according to the actual production situation in practical applications, as long as they can achieve the same effect as this invention.

[0032] Although the invention has been specifically shown and described in conjunction with preferred embodiments, those skilled in the art should understand that various changes in form and detail may be made to the invention without departing from the spirit and scope of the invention as defined in the appended claims, all of which shall be within the scope of protection of the invention.

Claims

1. A method for preparing pull-up trousers with an accordion waistband, characterized in that, Includes the following steps: S1, Prefabricated accordion waistband assembly: S11. Select a nonwoven fabric substrate layer; S12, Preparation of the elastic material layer: A continuous zigzag or sinusoidal path of the elastic material layer is sandwiched between two layers of nonwoven fabric substrate, or it is bonded to one side of a single layer of nonwoven fabric substrate by dispensing adhesive to form a three-dimensional pleated structure. The three-dimensional pleated structure includes a non-closed angled connecting part, a longitudinal connecting part located between two adjacent connecting parts, and a connecting part for connecting the end of the connecting part to the end of the nonwoven fabric substrate layer. The maximum opening angle of the connecting part is 120°-150°, the length of the longitudinal connecting part is 5-8mm, and the width of the connecting part is 2-3mm. The angle between the zigzag or sinusoidal path of the elastic material layer and the length direction of the pull-up pants is 30°-60°. S13. Reinforcing zones are formed at both ends of the nonwoven fabric substrate layer and the elastic material layer by means of hot pressing, adhesive bonding or ultrasonic welding. S2, Pull-up diaper body molding: S21. The impermeable bottom layer is transported longitudinally along the production line; S22. Rotate the cut absorbent cores 90° and lay them at equal intervals on the impermeable bottom layer; S23. Assemble the accordion waistband assembly prefabricated in step S1 onto the front waist area and / or back waist area of ​​the pull-up pants, and fix it together with the liquid-impermeable bottom layer and the end of the absorbent core. S24. Cover the absorbent core and the accordion waist assembly with the liquid-permeable surface layer and fix them together as one piece; S25. The leg opening is formed by arc cutting, then folded longitudinally, sealed on the side and cut into individual finished products.

2. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S1, the three-dimensional folded structure is in a compressed and folded state in its natural state, with a folding compression rate of 40%-60%. When stretched to its maximum length, the folds are fully unfolded without irreversible deformation.

3. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S12, the dispensing is done using intermittent dot matrix dispensing with a dot spacing of 3-5 mm.

4. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S11, the nonwoven substrate layer is a bicomponent spunbond thermally rolled nonwoven fabric.

5. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S12, the elastic material layer is spandex yarn with a denier of 300-500D.

6. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S12, the elastic material layer undergoes a pre-stretching-static-low temperature setting composite pretreatment process before configuration: first, it is stretched at 1.3-1.4 times the pre-stretching rate, and then static for 7-9 minutes; then, it is set at a low temperature of 42-48℃ for 3.5-4.5 minutes; after setting, it is naturally cooled to room temperature before being composited.

7. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S12, the zigzag path angle of the elastic material layer varies with the waist area, with the front waist area angle being 45° and the back waist area angle being 60°.

8. The method for preparing pull-up trousers with accordion waistband according to claim 1, characterized in that: In step S13, the welding pattern of the reinforcing zone is a continuous wavy shape, and the width of the reinforcing zone is 8-12mm.

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