JP2012125945A - Sealing device, sealing method and underpants type disposable diaper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sealing device and a sealing method which form a narrow-width linear sealed part.SOLUTION: The sealing device 1 includes a pair of processing rolls 10, 20 in which two rotors 11, 21 are arranged so that the rotation center lines 11, 22 of the respective rotors are parallel to each other. A plurality of sealing members 13, 23 are provided in one direction CD at a prescribed interval in a protruded fashion on respective outer circumferential surfaces 11a, 21a of the two rotors 11, 21. A material to be processed is compressed by the sealing member 13 (23) of one processing roll 10 (20) and the opposed surfaces of two sealing members 23, 23 (13, 13) adjacent in one direction CD which form the above prescribed interval of the other processing roll 20 (10).

Description

  The present invention relates to a sealing device and a sealing method for performing heat sealing processing on a workpiece, and a pants-type disposable diaper obtained by using the sealing device and the sealing method.

  In the manufacturing process of an article, a rotary processing device having a processing portion and a receiving portion that can move relative to each other in a direction approaching and separating from each other is used, and the processing portion is moved while the processing portion is rotated. Heat seal processing is widely performed in which a part or the whole of the workpiece is welded to form a seal portion by supplying between the base and the receiving portion. For example, a pants-type disposable diaper has conventionally formed a pair of side seals by joining both sides of the abdomen and both sides of the dorsal side by heat sealing, and forming a pair of waist openings and a pair of Manufactured by forming leg openings.

  Regarding heat seal processing, for example, Patent Document 1 discloses that a pair of embossing rolls having a plurality of convex portions formed on the outer peripheral surface thereof are aligned and rotated so that the convex portions always face each other, and both embossing rolls are used. A technique is described in which a bonding recess is formed by heating and pressing between sheets in between. This technique is known as so-called chip-to-chip embossing. According to the chip-to-chip embossing process, the sheet is heated and compressed between the convex parts facing each other. It is said that a nonwoven fabric suitable as a constituent material for sanitary goods such as diapers can be obtained.

  Patent Document 2 describes a sheet-like structure suitable as a constituent material of sanitary goods such as disposable diapers, and this sheet-like structure has a nonwoven fabric on at least one surface of a thermocompression-bondable elastic sheet. The elastic sheet and the nonwoven fabric are laminated and manufactured by thermocompression bonding of two thermocompression rolls facing each other at an arbitrary pattern of joints. A number of microprojections are formed on one outer peripheral surface of the two thermocompression-bonding rolls, and a number of recesses corresponding to the many microprojections are formed on the other outer peripheral surface. Sometimes, the tip of the minute protrusion comes into contact with the bottom of the recess in a planar manner via the workpiece. Due to the planar contact between the microprotrusions and the recesses at the time of thermocompression bonding, micro vent holes are formed in the sheet as the workpiece.

JP 2010-138529 A JP-A-6-328600

  In addition to having a practically sufficient seal strength, processed parts in sanitary goods that have been heat-sealed, such as disposable diapers, are flexible and gentle to the wearer's skin A good texture is required. Usually, when a sheet material such as a non-woven fabric is heat-sealed, the processed part (seal part) is cured by heat-sealing of the constituent fibers, so that the texture is lowered. Therefore, for example, in a disposable diaper, if the texture of the side seal part in which a large number of seal parts are formed is improved, the area of the processed part is reduced (for example, when the processed part is linear, the linear shape is reduced). It is necessary to devise measures such as reducing the width of

  However, when a pair of embossing rolls having a plurality of convex portions formed on the outer peripheral surface as described in Patent Document 1, for example, a linear seal portion is formed by subjecting a sheet such as a nonwoven fabric to heat sealing. In order to form a narrow seal portion by setting the width of the linear seal portion narrower than in the prior art, if the width of the convex portion of the embossing roll is narrowed, the strength of the convex portion decreases. For this reason, there is a possibility that the convex portion may be damaged at the time of narrow pressure of the workpiece, and the width of the convex portion cannot be easily reduced. There has not yet been provided a seal processing technique capable of forming a narrow linear seal portion effective in improving the texture of the workpiece.

  Accordingly, an object of the present invention is to provide a sealing device and a sealing method capable of forming a narrow linear seal portion. Moreover, the subject of this invention is providing the underpants type disposable diaper with the favorable texture of a side seal part.

  The present invention includes a pair of processing rolls in which two rotating bodies are arranged so that their rotation center lines are parallel to each other, and a plurality of seal members are provided on the outer peripheral surface of each of the two rotating bodies. The sheet-shaped workpiece passing between the rotating processing rolls is narrowed by the seal member, and a seal corresponding to the seal member is applied to the workpiece. A seal device for forming a portion, wherein the workpiece is formed by forming the gap between one of the processing rolls and the other of the processing rolls, and the two adjacent seals in the predetermined direction. The problem is solved by providing a sealing device that narrows the pressure between the opposing side surfaces of the member.

  The present invention also includes a pair of processing rolls in which two rotating bodies are arranged so that their rotation center lines are parallel to each other, and a plurality of seal members are provided on the outer peripheral surfaces of the two rotating bodies. A sheet-like workpiece that protrudes at a predetermined interval in a predetermined direction and passes between both rotating processing rolls is narrowed by the seal member, and the workpiece corresponds to the seal member. A sealing method using a sealing device for forming a seal portion, wherein the rotation of a pair of processing rolls is controlled so that the seal member of one of the processing rolls faces the interval of the other processing roll. And the workpieces, the sealing members of one of the processing rolls, and the opposing side surfaces of the two sealing members adjacent to each other in the predetermined direction, forming the gap between the other processing rolls. Narrow By providing a sealing method of, it is obtained by solving the above problems.

  Further, according to the present invention, the both sides of the abdomen and the sides of the dorsal side are joined together by the sealing method to form a pair of side seals, and a waist opening and a pair of leg openings. A pants-type disposable diaper having a longitudinal direction extending from the abdominal side part to the back side part through the crotch part, wherein the pair of side seal parts have a predetermined interval in the longitudinal direction. A plurality of linear seal portions formed are configured, and portions corresponding to the gaps in the sheet material constituting both sides of the abdominal side portion and the back side portion are alternately arranged in the longitudinal direction. By providing a pants-type disposable diaper that is uneven and corrugated, the above-mentioned problems are solved.

  According to the sealing device and the sealing method of the present invention, a narrow linear seal portion can be formed. The pants-type disposable diaper according to the present invention is a side seal portion in which a plurality of sheet materials are laminated and joined to each other at the seal portion, and the seal portion is a narrow linear seal portion. Excellent texture and appearance.

FIG. 1 is a perspective view of a main part (a pair of processing rolls) of an embodiment of the sealing device of the present invention. FIG. 2 is an enlarged perspective view of a portion surrounded by a circle indicated by a symbol P in FIG. FIG. 3 is an enlarged perspective view of a portion surrounded by a circle indicated by a symbol Q in FIG. FIG. 4 is a rotation center line of the processing roll showing a state in which the formation region of the sealing member of one processing roll faces the formation region of the sealing member of the other processing roll in the sealing device shown in FIG. It is sectional drawing of a direction (direction orthogonal to the running direction of a workpiece). FIG. 5 is a diagram illustrating a process of forming a seal portion on a workpiece using the sealing device illustrated in FIG. 1, and an upper diagram of FIG. 5A illustrates a traveling direction of the workpiece in the process. The cross-sectional view in the orthogonal direction, the lower part of FIG. 5A is a plan view showing the seal pattern of the seal part formed on the workpiece by the process, and FIG. It is a partially expanded sectional view of the upper figure of a). 6 (a) to 6 (c) show a state in which the formation region of the sealing member of one processing roll and the formation region of the sealing member of the other processing roll face each other in the sealing device of the present invention. It is sectional drawing of the rotation center line direction of this work roll which shows. FIG. 7 is a perspective view schematically showing a manufacturing process of a pants-type disposable diaper using the sealing device shown in FIG. FIG. 8 is a plan view schematically showing an intermediate product continuum of the pants-type disposable diaper manufactured in the manufacturing process shown in FIG. FIG. 9 is a plan view illustrating a state in which one embodiment of the pants-type disposable diaper of the present invention manufactured by the manufacturing process illustrated in FIG. 7 is partially broken and viewed from one surface side. FIG. 10 is a schematic side view of the side seal portion of the disposable diaper shown in FIG. 9. FIGS. 11A and 11B are views corresponding to FIG. 6 of the conventional sealing device, respectively.

  Hereinafter, the present invention will be described based on preferred embodiments with reference to the drawings. As shown in FIG. 1, the sealing device 1 according to the present embodiment includes a pair of processing rolls 10 and 20 in which two rotating bodies 11 and 21 are arranged so that their rotating shafts 12 and 22 are parallel to each other. I have. The rotating shaft 12 functions as a rotation center line of the rotating body 11 (working roll 10), and the rotating shaft 22 functions as a rotation center line of the rotating body 21 (working roll 20). A plurality of seal members 13 and 23 project from the outer peripheral surfaces 11a and 21a of the two rotating bodies 11 and 21, respectively. The sealing device 1 narrows the sheet-like workpiece passing between the rotating processing rolls 10 and 20 with the seal members 13 and 23, and seals the workpiece corresponding to the seal members 13 and 23. Is a device for forming

  More specifically, as shown in FIG. 1, the sealing device 1 includes a first processing roll 10 having a cylindrical rotating body 11 that is rotatably supported around a rotation shaft 12, and a roll 10 around a rotation shaft 22. And a second working roll 20 having a cylindrical rotating body 21 that rotates synchronously. When the rolls 10 and 20 (rotating bodies 11 and 21) are rotating, the sealing member 13 of the roll 10 is provided. And a seal member 23 of the roll 20 to form a seal portion on the workpiece supplied.

  As shown in FIG. 1, the first processing roll 10 includes two processing portions 14 that are formed on the outer peripheral surface 11 a of the rotating body 11 so as to protrude at substantially equal intervals in the circumferential direction. A plurality of seal members 13 are formed in a predetermined pattern on the upper surface. The second processing roll 20 also has a basic configuration similar to that of the roll 10, and a plurality of (two) processing portions 14 in the roll 10 corresponding to the outer peripheral surface 21 a of the rotating body 21 in a one-to-one relationship (two). Two (2) processed portions 24 are formed so as to protrude at substantially equal intervals in the circumferential direction, and a plurality of seal members 23 are formed in a predetermined pattern on the upper surface of each processed portion 24. Each member (rotating bodies 11 and 21, rotating shafts 12 and 22, sealing members 13 and 23, processed parts 14 and 24, etc.) constituting both rolls 10 and 20 includes a metal rigid body such as an aluminum alloy or steel. It consists of In addition, the number of the processing parts in the processing roll according to the present invention is not limited to two, and can be adjusted as appropriate in order to make the interval between the seal parts formed on the workpiece within a desired range. Individuals may be used.

  Each of the first processing roll 10 and the second processing roll 20 is provided with a heating means (not shown), and the heat conduction from the heating means causes the seal members 13 and 23 that come into contact with the workpiece to be processed. Heat is transmitted. Moreover, both rolls 10 and 20 are provided so that it may rotate synchronously when the driving force from a drive means (not shown) is transmitted to each rotating shaft 12 and 22. FIG.

  As shown in FIG. 2, the plurality of seal members 13 of the first processing roll 10 are projected from the CD with a predetermined interval 15. CD (Cross machine Direction) is a direction orthogonal to the running direction MD (Machine Direction) of the workpiece, and is parallel to the rotation center line of the rotating bodies 11 and 21. In the present embodiment, a plurality of seal members 13 and a plurality of intervals 15 are alternately formed on the CD at the tip of the processing portion 14 of the first processing roll 10 to form a row. A plurality of rows (two in this embodiment) are formed at predetermined intervals on the MD. In the row of the two seal members 13 adjacent to the MD, the seal members 13 and the interval 15 are adjacent to the MD, respectively.

  Each of the plurality of seal members 13 of the first processing roll 10 has an isosceles trapezoidal shape in which the width (length of the CD) gradually decreases toward the tip in the cross-sectional view of the CD as shown in FIG. The tip of each seal member 13 is a flat surface having a rectangular shape that is long in the MD in plan view (see FIG. 2), and has a pair of linear (straight) corners 13e extending in the MD. The interval 15 is a portion surrounded by the opposed inclined side surfaces 13s and 13s of the two isosceles trapezoidal seal members 13 and 13 adjacent to the CD, and has a width (CD) toward the bottom (rotating shaft 12 side). ) Is gradually decreasing.

  Further, as shown in FIG. 3, the plurality of seal members 23 of the second processing roll 20 are projected from the CD with a predetermined interval 25. In the present embodiment, a plurality of sealing members 23 and a plurality of intervals 25 are alternately formed on the CD at the tip of the processing portion 24 of the second processing roll 20 to form one row.

  Each of the plurality of seal members 23 of the second processing roll 20 has an isosceles trapezoidal shape as in the case of the seal member 13 in the cross-sectional view of the CD as shown in FIG. The front end of each seal member 23 is a flat surface having a long rectangular shape with respect to the MD in plan view (see FIG. 3), and has a pair of linear (linear) corners 23e extending to the MD. The interval 25 is a portion surrounded by the opposed inclined side surfaces 23s, 23s of the two isosceles trapezoidal seal members 23, 23 adjacent to the CD, and has a width (CD) toward the bottom (rotating shaft 22 side). ) Is gradually decreasing.

  In the present embodiment, as shown in FIG. 4, when the work piece is narrowly pressed, the seal member 13 (23) of one work roll 10 (20) has an interval 25 ( The rotation of the pair of processing rolls 10 and 20 is controlled so as to face 15). When the workpiece is under a narrow pressure, the opposing seal member 13 and the interval 25 and the opposing seal member 23 and the interval 15 are opposed to each other by matching the centers of the opposing seal member and the interval CD. To do.

  FIG. 5 shows a process of forming the seal portion 51 on the workpiece 50 using the seal device 1. The workpiece 50 is a laminated sheet in which a plurality of sheets (for example, four sheets) such as non-woven fabrics are overlapped, and the two sheets are joined to each other by an adhesive at a predetermined portion. In the present embodiment, as shown in FIG. 5, the workpiece 50 is separated from the seal member 13 (23) of one processing roll 10 (20) and the interval 25 (15) between the other processing roll 20 (10). The two sealing members 23, 23 (13, 13) adjacent to each other in the one-direction CD form a narrow pressure with the opposing side surfaces 23s, 23s (13s, 13s). That is, the narrow pressure by the seal members 13 and 23 of the work piece 50 is adjacent to the CD that forms the gap 25 between the seal member 13 of the first work roll 10 and the second work roll 20. Two adjacent to the CD that form a gap 15 between the sealing member 23 of the second processing roll 20 and the first processing roll 10 while narrowing the pressure between the opposing side surfaces 23s, 23s of the two sealing members 23, 23. This is done by narrowing the pressure between the opposing side surfaces 13s, 13s of the seal members 13, 13.

  In the present embodiment, when the pressure of the workpiece 50 is narrowed by the seal members 13 and 23, as shown in an enlarged view in FIG. Only a part enters the interval 25 of the second processing roll 20, and the seal member 23 of the second processing roll 20 also has a part on the tip side so as to enter the interval 15 of the first processing roll 10. The width and shape of each sealing member and the interval are set, and the tips of the sealing members 13 and 23 do not contact the bottoms of the opposing intervals 25 and 15. The seal members 13 and 23 are in contact with the inclined side surfaces 23s and 13s via the workpiece 50 only at the linear corners 13e and 23e extending to the MD at the tip.

  At this time, the workpiece 50 corresponds to the plurality of seal members 13 and 23 that slightly mesh with each other, as shown in FIG. And the site | part clamped between the corner | angular parts 13e and 23e of each sealing member 13 and 23 and side surface 23s and 13s is welded with the heat from the said heating means (not shown) attached to the processing rolls 10 and 20. Is done. As a result, as shown in FIG. 5A, a plurality of linear (straight) seal portions 51 extending in the MD are formed on the workpiece 50 at predetermined intervals. Each seal portion 51 is configured to include two straight lines extending in parallel with each other in the MD, and these two straight lines are portions where the pressure is most applied when the seal members 13 and 23 are narrowly pressed. The interval between the two seal portions 51, 51 adjacent to the CD in the workpiece 50 substantially matches the interval between the CDs of the corner portions 13 e, 23 e of the seal members 13, 23. The waved state of the work piece 50 at the time of narrow pressure is maintained even after the sealing process depending on the material of the work piece 50, the conditions of the sealing process, etc. A curved product is obtained.

  As described above, according to the sealing device 1 of the present embodiment or the sealing method using the sealing device 1, the corner 13 e at the tip of one seal member 13 and the side surface 23 s of the other seal member 23, and one seal Since the workpiece 50 is narrowed by the corner 23e at the tip of the member 23 and the side surface 13s of the other sealing member 13, the sealing members 13, 23 are caused by applying excessive force to the sealing members 13, 23 at the time of narrowing. It is possible to form a linear seal portion 51 that is narrower than the conventional one without causing any inconvenience such as breakage of the workpiece, thereby maintaining the original texture of the workpiece 50 as much as possible. It becomes.

  FIG. 11 shows an example of a conventional sealing device. The conventional sealing device shown in FIG. 11A includes a front end surface 91 of each of a plurality of seal members 90 protruding from the outer peripheral surface of one processing roll (rotating body) and the other end facing the front end surface 91. This is an apparatus for carrying out a sealing method for forming a seal portion by narrowing a workpiece (not shown) with an outer peripheral surface 92 of a processing roll (rotating body). Further, the conventional method shown in FIG. The sealing device seals the workpiece (not shown) by narrowing the pressure between the front end surface 91 of one seal member 90 and the front end surface 94 of the other seal member 93 having the same configuration as that of the seal member 90. It is an apparatus which implements the sealing method which forms a part. In these conventional sealing devices shown in FIG. 11, if a narrow linear seal portion is to be formed on the workpiece, the widths of the front end surfaces 91 and 94 (the length of the CD) W0 (FIG. 11 (b)). The seal members 90 and 93 need to be designed to be narrow, and if the seal members 90 and 93 are made narrow, the strength of the seal members 90 and 93 is reduced, and the work pressure is reduced. Sometimes, the seal members 90 and 93 may be damaged.

  On the other hand, as described above, the sealing device 1 of the present embodiment or the sealing method using the sealing device 1 has the corner 13e (23e) at the tip of one sealing member 13 (23) and the other sealing member 23 (13). ) Is narrowed with the side surface 23s (13s) of the sealing member 13 in spite of the fact that a narrow linear seal portion 51 as shown in FIG. 5A can be formed on the workpiece. , 23 can be made long enough so that the strength of the seal members 13 and 23 is not reduced, so that the strength of the seal members can be increased and narrow lines can be formed. The effect that a seal part of a shape can be formed can be produced. Therefore, this embodiment does not require the use of special members having high strength as the seal members 13 and 23, and is advantageous in terms of manufacturing cost.

  Further, as in the present embodiment, the workpiece is pressed on the side surface of the other seal member at the corner of the tip of the one seal member, so that the workpiece is relatively moved using the conventional seal device shown in FIG. When pressing with the two substantially parallel surfaces of the facing members (the front end surface of the seal member and the outer peripheral surface of the rotating member facing each other, or between the front end surfaces of the opposing seal members) (conventional seal) In comparison with the method, a strong pressure is applied to the part where the seal part is to be formed on the workpiece, so that a plurality of stacked sheets in the part where the seal part is to be formed are more closely contacted and the interlayer distance is reduced (thin thickness is reduced). Thus, the thermal conductivity of the part where the seal part is to be formed is improved, whereby the seal part 51 having a practically sufficient seal strength can be stably obtained.

  As described above, according to the sealing device 1 of the present embodiment or the sealing method using the same, the narrow linear seal portion 51 as shown in FIG. 5A can be formed. According to the present embodiment, the width (length of the CD) of the seal portion 51 can be set to 0.4 mm or less, and further 0.05 to 0.2 mm. Formation of such a narrow linear seal portion has been difficult with a conventional sealing device. Note that the width of the seal portion 51 can be adjusted to some extent by scraping the ends of the corner portions 13e and 23e of the seal members 13 and 23 to form flat inclined surfaces.

The dimensions and the like of each part in the sealing device 1 are not particularly limited, but are preferably set as follows from the viewpoint of ensuring the above-described effects.
The width W1 (see FIG. 4) of the tip of the seal member 13 is preferably 0.4 to 5.0 mm, more preferably 0.4 to 1.0 mm, and the width W2 of the tip of the seal member 23 (see FIG. 4). ) Is preferably 0.4 to 5.0 mm, more preferably 0.4 to 1.0 mm. The width W1 and the width W2 are the widths of the narrowest portion (tip portion) in the seal member.
The width W3 (see FIG. 4) of the interval 15 is preferably 0.5 to 5.0 mm, more preferably 0.5 to 1.0 mm, and the width W4 (see FIG. 4) of the interval 25 is preferably 0. .5 to 5.0 mm, more preferably 0.5 to 1.0 mm. The width W3 and the width W4 are the widths of the widest part (upper part) in the interval between the two seal members adjacent to the CD.

The protrusion height D1 (see FIG. 4) of the seal member 13 is preferably 1.0 to 3.0 mm, more preferably 1.0 to 1.5 mm, and the protrusion height D2 of the seal member 23 (see FIG. 4). ) Is preferably 1.0 to 3.0 mm, more preferably 1.0 to 1.5 mm.
The angle θ1 (see FIG. 4) of the side surface 13s of the seal member 13 with respect to the installation surface (the upper surface of the processed portion 14) is preferably 45 to 90 °, more preferably 75 to 85 °. The angle θ2 (see FIG. 4) with respect to the installation surface (the upper surface of the processed portion 24) is preferably 45 to 90 °, more preferably 75 to 85 °.

  One of the main features of the present invention is that, as described above, “the workpiece is narrowed by the sealing member of one processing roll (the corner of the sealing member) and the side surface of the sealing member of the other processing roll. The difference in the size of each part between one seal member and the other seal member can be an important factor in realizing such a narrow pressure method. For example, the width W1 (see FIG. 4) of the tip of one seal member 13 is smaller than the width W4 of the interval 25 of the other seal member 23 facing the seal member 13 (the maximum width of the interval 25; see FIG. 4). It must be larger than the minimum width W5 of the interval 25 (the width of the bottom of the interval 25, not shown). Similarly, the width W2 (see FIG. 4) at the tip of the other seal member 23 is smaller than the width W3 (the maximum width of the interval 15; see FIG. 4) of the interval 15 between the one seal member 13 opposed thereto. In addition, it needs to be larger than the minimum width W6 of the interval 15 (the width of the bottom of the interval 15; not shown).

  In addition, all of the embodiments shown in FIGS. 6A to 6C are included in the characteristic narrow pressure method of the present invention, but the form of the seal portion formed on the workpiece is different. Different. For example, as shown in FIG. 6A, when one of the sealing members 13 and the other sealing member 23 is an isosceles trapezoidal shape in the sectional view of the CD and the sectional shape of the CD is the same, When the angle θ1 of the side surface 13s of one seal member 13 and the angle θ2 of the side surface 23s of the other seal member 23 are the same and both are less than 90 ° (θ1 = θ2 <90 °), the one is formed on the workpiece. The linear seal portion is configured to include two parallel straight lines extending in the MD, such as the seal portion 51 shown in FIG.

  Further, as shown in FIGS. 6B and 6C, when one of the sealing members 13 and the other sealing member 23 has a different cross-sectional shape of the CD, a line formed on the workpiece. The shaped seal portion is composed of one straight line extending in the MD. In the embodiment shown in FIG. 6B, the cross sectional view of the CD of one seal member 13 is rectangular, and the cross sectional view of the CD of the other seal member 23 is an isosceles trapezoid. The angle θ1 of the side surface 13s is 90 ° or less, and the angle θ2 of the side surface 23s of the other seal member 23 is less than the angle θ1 (θ2 <θ1 ≦ 90 °). The embodiment shown in FIG. 6C is upside down from the embodiment shown in FIG. 6B, and θ1 <θ2 ≦ 90 °. From the viewpoint of sealing performance, at least one of the seal member 13 and the seal member 23 facing each other when the workpiece is narrowly pressed is an angle (the angles θ1, θ2) with respect to the installation surface (upper surface of the processing portion) of the side surface of the seal member. Is preferably less than 90 °.

  Next, the sealing method of the present invention using the above-described sealing device will be described based on a preferred embodiment applied to a method for manufacturing a pants-type disposable diaper. The manufacturing method of the diaper of this embodiment is a manufacturing method of a so-called cross-flow type pants-type disposable diaper as shown in FIG. 7, and the front end surface of the processing portion 14 in the first processing roll 10 using the sealing device 1 described above. And a diaper continuum 60 ′ (an intermediate continuum of pants-type disposable diapers) is supplied between the diaper and the front end surface of the processing portion 24 of the second processing roll 20 facing the front end surface. 60 'includes a step of forming a side seal portion 64 corresponding to the pattern of the seal members 13 and 23.

  More specifically, the manufacturing method of the diaper of the present embodiment includes 1) a step of forming a continuous body of the outer packaging material 61, and 2) an arrangement of the absorbent main body in which the absorbent main body 62 is disposed in the continuous body of the outer packaging material 61. Step, 3) Leg hole forming step of forming leg holes 63 in a continuous body of outer packaging material 61, 4) Folding process of continuous body of outer packaging material 61 and absorbent main body 62, 5) Outer packaging material 61 and absorbency A continuous body of diapers (intermediate product of underpants-type disposable diapers) 60 ′ in which the main body 62 is folded in half is placed by the sealing device 1 (not shown in FIG. 7) at a predetermined interval in the length direction. A step of forming a side seal portion 64 by heat-sealing, and 6) a separation step of cutting the continuum 60 ′ by the side seal portion 64 by a cutting means (not shown) and separating it into individual diapers 60. It has.

  In the step of forming the continuous body of the outer packaging material 61, the belt-shaped outer layer sheet 61A and the belt-shaped inner layer sheet 61B arranged on the skin side are joined to form a continuous body of the outer packaging material 61. In this embodiment, when these sheets are joined together, the waist elastic member 61C and the leg elastic member 61D are also supplied between these sheets and joined in an expanded state between them. Specifically, before the sheets 61A and 61B are overlapped, adhesion for fixing the waist elastic member 61C and the leg elastic member 61D to a predetermined part of one or both of the two sheets facing each other. An agent is applied in advance, and both belt-like sheets are narrowed with a nip roll in a state where these elastic members are sandwiched in an expanded state. The waist elastic member 61C is supplied to both side portions of the outer packaging material 61 so as to be positioned at the waist portion of the diaper, and is bonded and fixed with an adhesive. The leg elastic member 61D is supplied according to the form of the leg hole 63 and the crotch part to be formed later, and is joined and fixed with an adhesive. The leg elastic member 61D is introduced between the belt-like sheets 61A and 61B while being swung by a known rocking guide (not shown) in a direction orthogonal to the flow direction of the outer layer sheet 61A and the inner layer sheet 61B. Moreover, both the sheets 61A and 61B are joined to each other at a predetermined site by joining means such as various seals such as heat seal processing or an adhesive.

  In the arrangement process of the absorbent main body 62, the absorbent main body 62, which is separately manufactured and previously coated with an adhesive such as a hot melt adhesive, is rotated 90 degrees and intermittently placed on the inner layer sheet 61B of the continuous body of the outer packaging material 61. Supplied and fixed. The absorbent main body 62 includes a liquid-permeable top sheet, a liquid-impermeable or water-repellent back sheet, and a liquid-retaining absorbent disposed between the two sheets, and has a substantially vertically long form. have.

  In the leg hole forming step, the leg hole 63 is formed inside the annular portion of the leg elastic member 61D in the continuous body of the outer packaging material 61 in which the absorbent main body 62 is disposed. For the formation of the leg hole 63, a technique similar to the technique in the conventional manufacturing method of this type of article such as a rotary cutter and a laser cutter is employed. The leg hole can be formed before the absorbent main body 62 is arranged.

  In the folding step, both side edges of the continuous body of the outer packaging material 61 are folded in advance so as to be folded at both ends in the length direction of the waist elastic member 61C and the absorbent main body 62, and then the continuous body and absorption of the outer packaging material 61 are absorbed. The sex main body 62 is folded in half.

  In the step of forming the side seal portion 64, a diaper continuous body 60 ′ composed of a continuous body of the outer packaging material 61 folded together with the absorbent main body 62 is formed on the opposing first processing roll 10 in the sealing device 1. Supplyed between the processing section 14 and the processing section 24 of the second processing roll 20, and as described above, the corner 13e (23e) at the tip of one seal member 13 (23) and the other seal member 23 (13). ) Of the diaper continuum 60 ′ is narrowed with the side surface 23s (13s) of the diaper), thereby heat-sealing is performed. As a result, as shown in FIG. 8, the outer packaging material 61 (outer layer sheet 61A) of the diaper continuum 60 ′ In addition, a side seal portion 64 including a plurality of linear seal portions 64a having a seal pattern corresponding to the seal portions 13 and 23 is formed on the inner layer sheet 61B).

  In the separation step, the continuous body 60 ′ is cut and separated into individual diapers 60 at a substantially central portion of the side seal portion 64 of the diaper continuous body 60 ′ formed in the side seal portion forming step. For the separation of the diaper 60, a method similar to the method in the manufacturing method of this type of article is conventionally employed.

  FIG. 9 shows an outline of the pants-type disposable diaper 60 thus obtained. In the diaper 60, both side portions of the ventral side portion A and both side portions of the back side portion B are joined together by the sealing method of the present invention described above to form a pair of side seal portions 64, and a waist opening portion. 65 and a pair of leg openings 66 are formed, and have a longitudinal direction X extending from the abdominal side A to the back side B via the crotch C.

  The diaper 60 will be further described. The diaper 60 includes, when worn, an abdominal side A disposed on the wearer's abdomen, a back side B disposed on the back side, and a crotch C disposed therebetween. Both sides of the ventral side A and both sides of the dorsal side B are joined to each other in the vicinity of the respective side edge by the sealing method using the sealing device 1 described above. And by the joining, the strip | belt-shaped side seal part 64 is formed in the vicinity of the both-sides edge of the diaper 60 so that it may extend substantially in parallel with the longitudinal direction X (up-down direction of FIG. 9) of the diaper 60. A waist opening 65 is formed at the upper end in the longitudinal direction X, and leg openings 66 are formed on both sides of the crotch C. In FIG. 9, the dorsal side portion B is positioned on the far side of the ventral side portion A in a state of overlapping the ventral side portion A.

  The diaper 60 has an absorptive main body 62 that is formed substantially vertically long. The absorptive main body 62 has a longitudinal direction that coincides with the front-rear direction of the diaper 60, and abdominal side A and back side B It is arranged to span between. As described above, the absorbent main body 62 includes a liquid-permeable top sheet, a liquid-impermeable or water-repellent back sheet, and a liquid-retaining absorber interposed between the two sheets. Are joined and fixed to the inner surface side (inner layer sheet 61B) of the outer packaging material 61. The outer packaging material 61 forms the outer shape of the diaper.

  The diaper 60 is a waist flap portion as a portion extending from the position 62a in the longitudinal direction of the absorbent main body 62 to the peripheral edge 65a side of the waist opening 65 in each of the ventral side A and the back side B. In D, a plurality of waist elastic members 61C are respectively arranged in the circumferential direction of the waist opening 65 to form a waist gather. In addition, leg elastic members 61 </ b> D are arranged along the circumferential direction of the leg openings 66 at the peripheral edge of the leg openings 66 to form leg gathers. The outer packaging material 61 includes an outer layer sheet 61A that constitutes the outer surface of the diaper 60, an inner layer sheet 61B that is laminated and adhered to the inner surface side thereof, and elastic members 61C and 61D that are fixed between these sheets 61A and 61B. It consists of and.

  The state which looked at the side seal part 64 of the diaper 60 from the side surface is typically shown in FIG. As shown in FIG. 10, the side seal portion 64 includes a plurality of linear seal portions 64a formed at predetermined intervals in the longitudinal direction X of the diaper 60. In the outer packaging material 61 (outer layer sheet 61A and inner layer sheet 61B), which is a sheet material constituting the both side portions of the part B, portions corresponding to the interval are alternately undulated in the longitudinal direction X. Each seal portion 64a has a linear shape extending in a direction orthogonal to the longitudinal direction X (width direction of the diaper 60). The side seal portion 64 configured to include a laminated structure of the two sheets 61A and 61B is curved in a wave shape so that the direction of the unevenness changes with the seal portion 64a as a boundary in a side view as shown in FIG. .

  Each of the plurality of linear seal portions 64a constituting the side seal portion 64 can be formed narrow as described above, and by adopting such a narrow seal portion 64a, the side seal portion 64 is While having a practically sufficient seal strength, it is flexible and has a good texture friendly to the wearer's skin. Further, since the entire side seal portion 64 is curved in a wave shape so that the direction of unevenness changes from the seal portion 64a as a boundary, the seal portion 64a becomes difficult to be visually recognized from the outside, and the side seal portion 64 becomes a wave shape. The appearance of the side seal portion 64 and the appearance of the diaper 60 are improved in combination with the bending itself. From the viewpoint of more surely exhibiting the effect of the seal portion 64a, the number of the linear seal portions 64a in the side seal portion 64 is 1 cm in length in the longitudinal direction X of the side seal portion 64. Preferably it is 3-25, More preferably, it is 5-15.

  The material for forming the pants-type disposable diaper 60 will be described. As the outer layer sheet 61A and the inner layer sheet 61B constituting the outer packaging material 61, the same materials as those conventionally used for this type of diaper can be used. Nonwoven fabric, paper, resin film; a composite sheet obtained by combining these materials is used as a base sheet, and a sheet having a stretch property and a three-dimensional shape formed by subjecting the base sheet to a high stretching process. Further, as the elastic members 61C and 61D, those in which elastic materials such as natural rubber, polyurethane resin, urethane foam resin, and hot-melt elastic members are formed into a thread shape (thread rubber) or a belt shape (flat rubber) are preferable. Used.

  Moreover, as each member which comprises the absorptive main body 62, the thing similar to what was conventionally used for this kind of diaper can be used. As the top sheet, for example, liquid permeable sheets such as various non-woven fabrics and perforated films subjected to hydrophilic treatment can be used, and as the back sheet, for example, a thermoplastic resin film such as a polyethylene film, In addition, a liquid-impermeable or water-repellent sheet such as a laminate of the film and the nonwoven fabric can be used. As the absorbent, for example, a fiber assembly made of hydrophilic fibers such as wood pulp and synthetic fibers, or the like A fiber assembly in which a particulate high water-absorbing resin is held can be used, and the fiber assembly may be covered with a water-permeable sheet such as tissue paper.

  The present invention is not limited to the above-described embodiment and the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. For example, in the sealing device 1 of the above embodiment, the sealing members 13 and 23 are formed at the tips of the processing parts 14 and 24 that are formed to protrude from the outer peripheral surfaces 11a and 21a of the rotating bodies 11 and 21. The seal members 13 and 23 may be formed directly on the outer peripheral surfaces 11a and 21a without forming the pins 14 and 24.

  Further, in the sealing device and the sealing method of the present invention, the arrangement form of the seal member is not limited to the above-described embodiment, and can be selected as appropriate.Therefore, in the form of the seal portion that can be formed on the workpiece in the present invention, As shown in FIG. 5A, not only “a form in which a plurality of linear (straight) seal portions extending to the MD are formed at a predetermined interval on the CD” but also “a direction intersecting both the MD and CD directions”. A form in which a plurality of linear (straight-line) seal portions extending to the CD are formed at predetermined intervals on the CD ”or“ a plurality of linear (straight-line) seal portions extending to the CD are formed at predetermined intervals on the MD. Is also included.

  Further, the basic configuration of the pants-type disposable diaper of the present invention is as shown in FIG. 9 (when the pair of side seal portions 63 is broken to be in the expanded state, the abdominal side A, the crotch C, and the back side A pants-type disposable diaper comprising an outer packaging material 61 and an absorbent main body 62 fixed to the inner surface side of the outer packaging material 61, comprising one continuous sheet material having B in the longitudinal direction X) However, the following basic configuration may be used. That is, “both sides of the abdomen and both sides of the dorsal side are joined together by the sealing method (sealing method of the present invention) to form a pair of side seals, and a waist opening and A pair of leg-opening diapers having a longitudinal direction extending from the abdominal side to the back side through the crotch and fixed to the outer packaging material and the inner surface side of the outer packaging material. A pants-type disposable diaper comprising an absorbent main body, wherein the outer packaging material includes a first sheet material constituting the abdomen side portion and a second sheet material constituting the back side portion. The first sheet material and the second sheet material are disposed apart from each other in the longitudinal direction when the pair of side seal portions are broken and the disposable diaper is in an expanded state. The absorbent body is It is a pants-type disposable diaper between the sheet material and the second sheet material is arranged so as to cross the longitudinal direction ". In the pants-type disposable diaper having such a configuration, the outer packaging material does not exist in the whole or part of the crotch part, and these parts are constituted by the absorbent main body.

  The sealing device and the sealing method of the present invention can be used in various industries depending on the workpiece. The present invention is particularly suitable for the production of pants-type absorbent articles such as pants-type disposable diapers, pants-type sanitary napkins, pants-type incontinence pads, etc., but does not include an absorbent main body or absorbent body, sanitary shorts, etc. It is also suitable for manufacturing pants-type wearing articles.

DESCRIPTION OF SYMBOLS 1 Sealing device 10, 20 Work roll 11, 21 Rotating body 11a, 21a, 92 Outer peripheral surface 12, 22 of rotating body Rotating shaft (rotation center line)
13, 23, 90, 93 Seal members 14, 24 Processing portions 15, 25 Seal member spacing 50 Work piece 51 Seal portion 60 Pants-type disposable diaper 60 'Diaper continuum 61 Outer packaging material 62 Absorbent body 64 Side seal portion 64a Seal part MD constituting the side seal part Traveling direction CD of the workpiece CD Direction orthogonal to the traveling direction of the workpiece

Claims (3)

The two rotators are provided with a pair of processing rolls arranged so that the rotation center lines thereof are parallel to each other, and a plurality of seal members are predetermined in predetermined directions on the outer peripheral surfaces of the two rotators. The sheet-like workpiece passing between both rotating processing rolls is narrowed by the seal member, and a seal portion corresponding to the seal member is formed on the workpiece. A sealing device,
The workpiece is narrowed by the sealing member of one of the processing rolls and the opposing side surfaces of the two sealing members adjacent to each other in the predetermined direction that form the gap between the other processing rolls. Sealing device. The two rotators are provided with a pair of processing rolls arranged so that the rotation center lines thereof are parallel to each other, and a plurality of seal members are predetermined in predetermined directions on the outer peripheral surfaces of the two rotators. The sheet-like workpiece passing between both rotating processing rolls is narrowed by the seal member, and a seal portion corresponding to the seal member is formed on the workpiece. A sealing method using a sealing device,
The rotation of a pair of the processing rolls is controlled so that the seal member of one of the processing rolls is opposed to the distance between the other processing rolls, and the workpiece is A sealing method in which a pressure is applied between a sealing member and each of the opposing side surfaces of the two sealing members adjacent to each other in the predetermined direction, which form the gap between the other processing rolls. The both side portions of the ventral side portion and both side portions of the back side portion are joined to each other by the sealing method according to claim 2 to form a pair of side seal portions, and a waist opening portion and a pair of leg opening portions are formed. A pants-type disposable diaper that is formed and has a longitudinal direction from the abdominal side part to the back side part through the crotch part,
The pair of side seal portions includes a plurality of linear seal portions formed at predetermined intervals in the longitudinal direction, and constitutes both sides of the ventral side portion and the dorsal side portion. A pants-type disposable diaper in which a portion corresponding to the interval in the material is undulated alternately in the longitudinal direction.

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