TW201827233A - Composite sheet manufacturing method and manufacturing apparatus - Google Patents

Abstract

A composite sheet manufacturing method is provided with: a step of introducing a first sheet (1) into a meshing part (33) and deforming the first sheet (1) into a concavo-convex shape while rotating a first roll (31) and a second roll (32) having meshing concavities and convexities on peripheral surface parts thereof; a step of conveying the first sheet (1), deformed into the concavo-convex shape, while carrying the same on the first roll (31), and overlapping a second sheet (2) with the first sheet (1) being conveyed; and a step of sandwiching the overlapped sheets (1 and 2) between a convex part (35) of the first roll (31) and an ultrasonic horn (42) of a ultrasonic welding machine, and applying ultrasonic vibrations. During the application of the ultrasonic vibrations in the ultrasonic treatment step, a welded part (4) having a through-hole (14) is formed.

Description

Method and device for manufacturing composite sheet

The invention relates to a method and a device for manufacturing a composite sheet.

As a surface sheet of an absorbent article such as a disposable diaper or a menstrual tampon, it is known that an unevenness is formed on a surface abutting on the wearer's skin. For example, the present applicant proposes a composite sheet having a plurality of fused portions where the first and second sheets are fused, and a portion other than the fused portion of the first sheet is formed to be opposite to the second sheet side Projections protruding sideways. Since this composite sheet has irregularities formed on the surface, it has excellent skin feel and prevention of liquid diffusion. It is also known to form a through hole in a fused portion in such a composite sheet to improve liquid introduction properties and the like (see Patent Documents 1 and 2). In Patent Document 2, it is also described that in order to form a fused portion having a through hole, a small protrusion for forming an opening having a step difference from the surrounding shoulder portion is provided at the front end portion of the convex portion of the uneven roller. The two sheets are sandwiched between the small convex portion and the anvil roll and heated to form a fused portion having an opening. [Prior Art Literature] [Patent Literature] Patent Literature 1: Japanese Patent Laid-Open No. 2006-175688 Patent Literature 2: Japanese Patent Laid-Open No. 2006-175689

The present invention is a method for manufacturing a composite sheet, the composite sheet having a plurality of fused portions where the first sheet and the second sheet are fused, and at least a part of the first sheet except for the fused portion A convex portion is formed to protrude to the side opposite to the second sheet side. The manufacturing method of the composite sheet is provided with a forming step of rotating the first roller and the second roller that have irregularities that engage with each other on the peripheral surface, and introducing the first sheet to the meshing portion of the two rollers while rotating. And deforming it into a concave-convex shape; in the overlapping step, the first sheet deformed into the concave-convex shape is conveyed while being held on the first roller, and the second sheet is superimposed on the first sheet being conveyed And an ultrasonic processing step of sandwiching the two overlapping sheets between the convex portion of the first roller and the ultrasonic welding head of the ultrasonic fusion machine to apply ultrasonic vibration. In the above-mentioned ultrasonic processing step, when the ultrasonic vibration is applied, the fused portion having a through hole is formed. In addition, the present invention is a device for manufacturing a composite sheet, the composite sheet having a plurality of fusion portions where the first sheet and the second sheet are fused, and a portion of the first sheet other than the fusion portion At least a part is formed with a convex portion protruding to a side opposite to the second sheet side. The manufacturing apparatus of this composite sheet is provided with a concave-convex forming portion having a first roller and a second roller having convex and concave portions that mesh with each other on a peripheral surface portion, and the first sheet introduced into the meshing portion of the two rollers. Deformed into a concave-convex shape; and an ultrasonic processing unit including an ultrasonic fusion machine, and after superimposing the second sheet on the first sheet deformed into a concave-convex shape, the two sheets It is sandwiched between the convex part of the said 1st roll and the ultrasonic welding head of the said ultrasonic fusion machine, and ultrasonic vibration is applied locally, and the said fusion | melting part which has a through-hole is formed.

In the production of a composite sheet, if the formation of the fusion portion and the formation of the through-holes are performed by different steps, a positional shift may occur between the position of the fusion portion and the position of the through-hole. In addition, Patent Document 2 In the described method of providing a small convex part at the front end of the convex part, the small convex part is easy to wear, and there is room for improvement in terms of a large maintenance burden. Therefore, the present invention relates to a method and a device for manufacturing a composite sheet which can solve the problems of the prior art. Hereinafter, based on the preferred embodiment of the present invention, the present invention will be described with reference to the drawings. First, referring to FIG. 1, a composite sheet produced by the method or device for producing a composite sheet of the present invention will be described. The composite sheet 10 shown in FIG. 1 is an example of a composite sheet manufactured by the method or apparatus for manufacturing a composite sheet of the present invention. As shown in FIG. 1, the composite sheet 10 includes a first sheet 1 and a second sheet 2. The plurality of fused portions 4 are fused, and at least a part of the portion other than the fused portion 4 in the first sheet 1 is formed with a convex portion 5 protruding toward the opposite side from the second sheet 2 side. The composite sheet 10 is preferably used as a surface sheet or the like of an absorbent article. When used as a surface sheet of an absorbent article, the first sheet 1 forms a surface facing the wearer's skin side (hereinafter, also referred to as a skin-facing surface), and the second sheet 2 forms an absorbent body when worn. Side surface (hereinafter, also referred to as non-skin facing surface). The convex portions 5 and the fused portions 4 are arranged alternately and in a row in a direction parallel to the surface of the composite sheet 10, that is, in the X direction in FIG. 1. This line is parallel to the surface of the composite sheet 10 and The direction orthogonal to the above-mentioned one direction, that is, the Y direction in FIG. 1 is formed in a plurality of lines. The convex portions 5 and the fused portions 4 in the mutually adjacent rows are respectively arranged to be shifted in the X direction, and more specifically, they are arranged to be shifted by a half pitch. In the composite sheet 10, the Y direction is consistent with the traveling direction (MD, mechanical direction) during manufacturing, and the X direction is consistent with the direction (CD) orthogonal to the traveling direction during manufacturing. The first sheet 1 and the second sheet 2 include a sheet material. As the sheet material, for example, a fibrous sheet or a film such as a non-woven fabric, a woven fabric, and a knitted fabric can be used. From the viewpoint of skin feel and the like, a fibrous sheet is preferably used, and a non-woven fabric is particularly preferred. The types of the sheet materials constituting the first sheet 1 and the second sheet 2 may be the same or different. Examples of the nonwoven fabric in the case where a nonwoven fabric is used as a sheet material constituting the first sheet 1 and the second sheet 2 include, for example, a hot air nonwoven fabric, a spunbond nonwoven fabric, a spunlace nonwoven fabric, a meltblown nonwoven fabric, a resin adhesive nonwoven fabric, Needle-punched non-woven fabrics, etc. A laminated body obtained by combining two or more kinds of these non-woven fabrics or a laminated body obtained by combining these non-woven fabrics and films can also be used. The basis weight of the nonwoven fabric used as the sheet material constituting the first sheet 1 and the second sheet 2 is preferably 10 g / m ² Above, more preferably 15 g / m ² Above, and preferably 40 g / m ² Below, more preferably 35 g / m ² the following. The basis weight of the non-woven fabric is preferably 10 g / m ² Above 40 g / m ² Below, more preferably 15 g / m ² Above 35 g / m ² the following. As the fibers constituting the nonwoven fabric, fibers including various thermoplastic resins can be used. As the sheet material other than the non-woven fabric, a constituent fiber or a constituent resin can be preferably used including various thermoplastic resins. Examples of the thermoplastic resin include polyolefins such as polyethylene, polypropylene, and polybutene, polyesters such as polyethylene terephthalate and polybutylene terephthalate, polyamides such as nylon 6, nylon 66, and the like. Polyacrylic acid, polyalkyl methacrylate, polyvinyl chloride, polyvinylidene chloride, etc. These resins can be used alone or as a mixture of two or more. Moreover, it can be used in the form of a composite fiber such as a core-sheath type or a side-by-side type. As shown in FIG. 1, the composite sheet 10 has a plurality of recesses 3 sandwiched between the protrusions 5 on the surface of the first sheet 1 side in two directions of the X direction and the Y direction, and is formed at the bottom of each recess 3. There is a fused portion 4 having a through hole 14. When viewed as a whole, the surface of the composite sheet 10 on the side of the first sheet 1 has unevenness including the undulations 3 and the protrusions 5 on the side, and the surface on the side of the second sheet 2 is flat, or it is relatively The surface on one side of one sheet is a substantially flat surface with relatively small fluctuations. As shown in FIG. 2, each of the fusion portions 4 in the composite sheet 10 has a substantially rectangular plan view shape that is longer in the Y direction, and a through hole 14 having a substantially rectangular plan view shape is formed inside each of them. In other words, each of the fused portions 4 is formed in a ring shape surrounding the through hole 14. It is preferable that only one through hole 14 is formed in one fused portion 4, and it is preferable that the through hole 14 is formed in a specific position determined in advance in relation to the position of the fused portion 4. In addition, the shape of the through hole 14 in plan view may be similar to the shape of the outer periphery of the fused portion 4 or may be a dissimilar shape, but a similar shape is preferred. In the fusion section 4, the first sheet 1 and the second sheet 2 are joined by melting and solidifying a heat-fusible resin constituting at least one of the first sheet 1 and the second sheet 2. When the first sheet 1 and the second sheet 2 include a fibrous sheet such as a non-woven fabric, in the fusion section 4, the constituent fibers of the first sheet 1 and the second sheet 2 are preferably melted or buried to melt The resin cannot be visually observed in a fibrous state, that is, it is in a state of being film-formed. Next, a first embodiment of the method for manufacturing a composite sheet of the present invention will be described. In the first embodiment, the above-mentioned composite sheet 10 is manufactured using the composite sheet manufacturing apparatus 20 of the first embodiment shown in FIG. 3. If the manufacturing apparatus 20 for a composite sheet shown in FIG. 3 is described, the manufacturing apparatus 20 for a composite sheet is provided with a concave-convex shaping part 30, an ultrasonic processing part 40, and a preheating mechanism 6, which The sheet is preheated to a controlled temperature before the ultrasonic vibration is applied. As shown in FIG. 3, the concave-convex forming portion 30 has first and second rollers 31 and 32 having irregularities that engage with each other on the peripheral surface portion, and the two rolls 31 and 32 are rotated by one side and the first sheet 1 It is introduced into the meshing portion 33 of the two rollers 31 and 32 to deform the first sheet 1 into a concave-convex shape having a concave-convex shape along the peripheral surface of the first roller 31. FIG. 4 is an enlarged perspective view showing a main part of the first roller 31. A part of the peripheral surface of the first roller 31 is shown in FIG. 4. The first roller 31 is formed by combining a plurality of spur gears 31a, 31b, ... having a specific tooth width into a roll shape. The teeth of each gear form a concave-convex convex portion 35 in the peripheral surface of the first roller 31. The front end surface 35c of the convex portion 35 is between the front end surface 42t of the ultrasonic welding head 42 of the ultrasonic fusion machine 41 described below. A pressing surface for pressing the first and second sheets 1 and 2 to be fused. The tooth width (length of the gear in the axial direction) of each gear determines the size of the X direction in the convex portion 5 of the composite sheet 10, and the thickness of the teeth of the gear (length of the gear in the rotation direction) determines the size of the composite sheet 10. The dimension in the above-mentioned Y direction in the convex portion 5. Adjacent gear trains are combined in such a way that the pitch of their teeth is offset by half a pitch, respectively. As a result, the peripheral surface portion of the first roller 31 has an uneven shape. In this embodiment, the front end surface 35c of each convex portion 35 has a rectangular shape in which the rotation direction of the first roller 31 is a long side and the axial direction is a short side. If the front end surface 35c has a long shape in the rotation direction, it is preferable that the contact time between one of the convex portions 35 of the first roller 31 and the front end surface 42t of the ultrasonic horn 42 becomes longer and the temperature is easily increased. The cogging portion of each gear in the first roller 31 forms a concave and convex concave portion on the peripheral surface of the first roller 31. A suction hole 34 is formed in the bottom of the cogging portion of each gear. The suction hole 34 is connected to a suction source (not shown) such as a blower or a vacuum pump, so that the suction portion 34 extends from the engagement portion 33 of the first roller 31 and the second roller 32 to the confluence portion of the first sheet 1 and the second sheet 2. The manner in which suction is performed until now is controlled. Therefore, the first sheet 1 deformed into a concave-convex shape by the engagement of the first roller 31 and the second roller 32 is maintained to be deformed along the first roller 31 by the suction force of the suction hole 34. The state of the shape of the unevenness is conveyed to the confluence part of the first sheet 1 and the second sheet 2 and the ultrasonic vibration application part 36 using an ultrasonic fusion machine. In this case, as shown in FIG. 4, if a specific gap G is provided between adjacent gears, it is possible to suppress excessive stretching force from being applied to the first sheet 1 or the meshing portion 33 of the two rollers 31 and 32. It is preferable to cut the first sheet 1 to deform the first sheet 1 into a shape along the peripheral surface of the first roller 31. The second roller 32 has a concavo-convex shape on the peripheral surface portion which meshes with the concavities and convexities on the peripheral surface portion of the first roller 31. The second roller 32 has the same configuration as the first roller 31 except that it does not have the suction hole 34. In addition, the first sheet 1 is introduced into the meshing portion 33 of the two rollers 31 and 32 while the first and second rollers 31 and 32 having the mutually engaging irregularities are rotated, and the first sheet 1 can be deformed. It is a concave-convex shape. In the engaging portion 33, a plurality of portions of the first sheet 1 are pressed into the concave portions of the peripheral surface of the first roller 31 by the convex portions of the second roller 32, and the pressed portions become the manufactured composite sheet 10 The convex part 5. A plurality of convex portions are formed on the peripheral surface of the second roller 32 and are inserted into the concave portions of the first roller 31. As shown in FIG. 3, the ultrasonic processing unit 40 is provided with an ultrasonic fusion machine 41 having an ultrasonic welding head 42 to superimpose the second sheet 2 on the first sheet 1 which is deformed into an uneven shape, and then The two sheets are sandwiched between the convex portion of the first roller 31 and the ultrasonic horn 42 to locally apply ultrasonic vibration to form a fusion portion 4 having a through hole 14. As shown in FIGS. 3 and 5, the ultrasonic fusion machine 41 includes an ultrasonic oscillator (not shown), a converter 43, an accelerator 44, and an ultrasonic welding head 42. An ultrasonic oscillator (not shown) is electrically connected to the converter 43, and a high-voltage electric signal having a frequency of about 15 kHz to 50 kHz generated by the ultrasonic oscillator is input to the converter 43. An ultrasonic oscillator (not shown) is provided on or outside the movable table 45. The transducer 43 includes a piezoelectric element such as a piezoelectric element, and converts an electric signal input from the ultrasonic oscillator into a mechanical vibration by the piezoelectric element. The amplitude adjustment of the mechanical vibration emitted from the converter 43 by the accelerator 44 is preferably amplified and transmitted to the ultrasonic welding head 42. The ultrasonic horn 42 is formed of a metal block such as an aluminum alloy or a titanium alloy, and is designed to accurately resonate according to the frequency used. The ultrasonic vibration transmitted from the accelerator 44 to the ultrasonic horn 42 is amplified or attenuated inside the ultrasonic horn 42 and then applied to the first and second sheets 1 and 2 as fusion targets. As this ultrasonic fusion machine 41, a commercially available ultrasonic welding head, converter, accelerator, and ultrasonic oscillator can be used in combination. The ultrasonic fusion machine 41 is fixed on the movable table 45, and by moving the position of the movable table 45 toward the direction close to the peripheral surface of the first roller 31, the front end face 42t of the ultrasonic welding head 42 and the first roller 31 can be adjusted. The gap between the front end surface 35c of the convex portion 35 and the pressing force applied to the laminated first and second sheets 1 and 2. Furthermore, the pressure is sandwiched between the front end surface 35c of the convex portion 35 of the first roller 31 and the front end surface 42t of the ultrasonic welding head 42 of the ultrasonic fusion machine 41, and the first and the first objects to be fused are pressed. The two sheets 1 and 2 are subjected to ultrasonic vibration, and each of the portions of the first sheet 1 located on the front end surface 35c of the convex portion 35 is fused to the second sheet 2 to form a fusion portion 4, and the two The through holes 14 of the sheets 1 and 2 are formed in a state surrounded by the molten portion. In a preferred embodiment, the manufacturing apparatus 20 for the composite sheet includes a preheating mechanism 6 having a heater 61 disposed in the first roller 31. More specifically, it includes a heating mechanism such as a heater 61 disposed in the first roller 31, a temperature measuring mechanism (not shown) capable of measuring the temperature of the sheet before ultrasonic vibration is applied, and measurement by the temperature measuring mechanism A temperature control unit (not shown) that controls the temperature of the heater 61. By controlling the heating temperature of the peripheral surface of the first roller 31 by the heater 61 by the measured value based on the temperature measurement mechanism, the temperature of the first sheet 1 immediately before the ultrasonic vibration is applied can be accurately controlled. Expected temperature. In a preferred embodiment, the heater 61 is fitted into the first roller 31 along its axial length direction. Further, the heaters 61 are arranged in the vicinity of the outer periphery of the rotation axis of the first roller 31 and are arranged in the circumferential direction with a plurality of them. The heating temperature of the peripheral surface of the first roller 31 by the heater 61 is controlled by a temperature control section (not shown), and the composite sheet manufacturing apparatus 20 can be introduced to the ultrasonic vibration application section 36 during operation. The temperature of the first sheet 1 is maintained at a specific range of temperature. The preheating mechanism 6 is preferably provided with a heating mechanism that applies heat energy to the object to be heated from the outside and heats it. Examples of the heating mechanism include a cassette heater using an electric heating wire, but the invention is not limited to this, and various known heating mechanisms can be used without particular limitation. The ultrasonic fusion machine applies ultrasonic vibration to a fusion object, thereby heating and melting the fusion object to fuse, and does not include the heating mechanism mentioned here. In the manufacturing method according to the first embodiment of the present invention, as shown in FIG. 3, while rotating the first and second rolls 31 and 32, the first sheet rolled out from the raw sheet roll (not shown) 1 is introduced into the meshing portion 33 of the two rollers 31 and 32 to deform it into a concave-convex shape (forming step). Then, the first sheet 1 deformed into a concave-convex shape is conveyed while being held on the first roll 31, and the second sheet 2 rolled out from a raw sheet roll (not shown) different from the first sheet 1 is conveyed. Superimposed on the first sheet 1 being conveyed (overlapping step). Then, the overlapping two sheets 1 and 2 are sandwiched between the convex portion 35 of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine to apply ultrasonic vibration (ultrasonic processing step). In the ultrasonic processing step, when ultrasonic vibration is applied, a fusion portion 4 having a through hole 14 is formed. In the manufacturing method of the first embodiment, it is preferable that at least one of the first sheet 1 and the second sheet 2 is heated in advance to a temperature below the melting point of the sheet, before the ultrasonic vibration is applied. It is more than 50 ° C lower than the melting point. That is, it is preferable to perform any one or both of the following (1) and (2) before the ultrasonic vibration is applied. (1) The first sheet 1 is heated in advance to a temperature that does not reach the melting point of the first sheet and is 50 ° C lower than the melting point. (2) The second sheet 2 is heated in advance to a temperature that does not reach the melting point of the second sheet and is 50 ° C lower than the melting point. Preferably, the first sheet 1 is heated in advance to a temperature that does not reach the melting point of the first sheet and is 50 ° C lower than the melting point, and the second sheet 2 is heated in advance to the second sheet. The melting point of the material is at least 50 ° C lower than the melting point. As a method of making the first sheet 1 less than the melting point of the first sheet 1 and a temperature that is 50 ° C. or more lower than the melting point, for example, the meshing portion 33 of the first and second rollers 31 and 32 and Yuchao The temperature of the first sheet 1 on the first roller 31 is measured between the ultrasonic vibration application unit 36 performed by the sonic fusion machine, and the circumference of the first roller 31 is controlled so that the measured value falls within the above-mentioned specific range. Face temperature. As a method for preheating the first sheet 1 to a temperature in a specific range, instead of making the first sheet 1 into a temperature in a specific range, the first roller 31 may be controlled by a heater disposed in the first roller 31. Various methods can be used to measure the temperature of the face. For example, the heater may be provided near the peripheral surface of the first roller 31, a hot air outlet, and a far-infrared irradiation device, and the first roller may be controlled before or after along the first sheet 1 by these. A method of heating the peripheral surface of the 31st sheet; a method of heating the second roller 32 in contact with the first sheet 1 in the engaging portion 33 and controlling the temperature of the first sheet 1 by controlling the temperature of the peripheral surface; and The first sheet 1 along the first roller 31 is brought into contact with a heating roller or passed through a space maintained at a high temperature or a method of blowing hot air. On the other hand, as a method for making the second sheet 2 a temperature lower than the melting point of the second sheet and at a temperature of 50 ° C. or more lower than the melting point, it is preferable that the second sheet 2 be merged with the first sheet 1 The temperature of the sheet is measured by a temperature measuring mechanism arranged in the conveying path of the second sheet, and the measurement value of the sheet is controlled to be within the above-mentioned specific range, and the temperature of the second sheet disposed in the conveying path of the second sheet is controlled. Temperature of heating mechanism (not shown). The heating mechanism of the second sheet may be a contact method such as contacting heated rollers or the like, or a non-contact method such as maintaining a high temperature space, blowing hot air, penetrating or irradiating the outer line of a hole. The melting points of the first sheet 1 and the second sheet 2 are measured by the following methods. For example, a differential scanning calorimetry (DSC, Pyris Diamond DSC) manufactured by Perkin-Elmer is used for measurement. The melting point was calculated from the peak value of the measurement data. When the first sheet 1 or the second sheet 2 is a fibrous sheet such as a non-woven fabric, and the constituent fibers are composite fibers including a plurality of components such as a core-sheath type and a side-by-side type, the melting point of the sheet will be calculated by Among the plurality of melting points measured by DSC, the melting point of the lowest temperature is the melting point of the composite fiber sheet. In the manufacturing method of the composite sheet of the first embodiment, the overlapping first and second sheets 1 and 2 are sandwiched between the convex portion of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine. Ultrasonic vibration is applied from time to time to form a fused portion 4 having a through hole 14. In the manufacturing method of the composite sheet of the first embodiment, it is preferable that at least one of the first and second sheets 1 and 2 is pre-heated to a temperature within the above-mentioned specific range where the sheet does not melt, and then , Ultrasonic vibration is applied to the two sheets 1 and 2 in a state where one or both are preheated. At this time, the conditions when applying the ultrasonic vibration are adjusted, for example, the wavelength and intensity of the applied ultrasonic vibration, the pressure for pressing the two sheets 1, 2 and the like, and the two sheets 1 are ultrasonically vibrated. 2 and 2 are melted to form a fused portion 4, and the through-holes 14 penetrating through the two sheets 1 and 2 are formed in a state surrounded by the melted portion. According to the method for manufacturing a composite sheet according to the first embodiment, at least one of the first sheet 1 and the second sheet 2 is preferably heated to the sheet in advance by a heating mechanism such as a heater. The temperature is not high enough to melt, and then ultrasonic vibration is applied between the convex portion 35 of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine to form a fusion portion 4 having a through hole 14, Thereby, compared with the case where the two sheets 1, 2 are not preheated, the fusion portion 4 having the through holes 14 can be formed more reliably, and it is less likely to occur that the two sheets 1, 2 are preheated to exceed Defects that easily occur in the case of the temperature of the melting point, for example, the adhesion of the molten resin to the conveying mechanism or the winding of the sheet to the conveying roller, so the maintenance burden on the device is also small. In addition, since the formation of the fusion portion 4 and the formation of the through hole 14 are performed simultaneously between the convex portion 35 of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine, the position and penetration of the fusion portion 4 are formed. There is also no positional shift between the positions of the holes 14. The composite sheet 10 obtained by the method for manufacturing a composite sheet according to the first embodiment has irregularities, and has a fused portion 4 at the bottom of the recessed portion. The fused portion 4 has a through hole 14. The liquid has excellent diffusion prevention properties, and also has excellent air permeability or liquid introduction properties. The composite sheet 10 exhibits this characteristic and is preferably used as a surface sheet of an absorbent article, but the use of the composite sheet 10 is not limited to this. From the viewpoint of more reliably exerting one or more of the effects described above, the manufacturing method and manufacturing apparatus of the present invention preferably have the following configurations. (1) The first sheet 1 is preferably preheated to a temperature that is 50 ° C lower than the melting point of the first sheet 1 and does not reach the melting point, and more preferably it is preheated to a temperature lower than the melting point of the first sheet 1 Above 20 ° C and below 5 ° C below the melting point. (2) The second sheet 2 is preferably preheated to a temperature that is 50 ° C lower than the melting point of the second sheet 2 and does not reach the melting point, and more preferably is preheated to a temperature lower than the melting point of the second sheet 2 A temperature above 20 ° C and below 5 ° C below the melting point. The preheating temperature of each of the first sheet 1 and the second sheet 2 is preferably 100 ° C. or higher, more preferably 130 ° C. or higher, from the viewpoint of easily forming the through-holes 14. From the viewpoint of adhesion or prevention of winding on the conveying roller, it is preferably 150 ° C or lower, and more preferably 145 ° C or lower. In addition, from the viewpoint of easily forming the fused portion 4 and the through hole 14, it is sandwiched between the front end surface 35c of the convex portion 35 of the first roller 31 and the front end surface 42t of the ultrasonic horn 42 and is applied to the first and second pieces. The pressing force of the materials 1 and 2 is preferably 10 N / mm or more, more preferably 15 N / mm or more, more preferably 150 N / mm or less, even more preferably 120 N / mm or less, and more preferably 10 N / mm or more and 150 N / mm or less, more preferably 15 N / mm or more and 120 N / mm or less. The applied pressure referred to here is the so-called linear pressure, which is the sum of the applied pressure (N) of the ultrasonic welding head 42 divided by the tooth width (X direction) of the convex portion 35 in contact with the ultrasonic welding head 42 (excluding the first The value (the pressure per unit length) obtained by the length of the concave portion of 1 roll 31 is expressed. Further, from the viewpoint of easily forming the fused portion 4 and the through hole 14, the frequency of the applied ultrasonic vibration is preferably 15 kHz or more, more preferably 20 kHz or more, and more preferably 50 kHz or less, and more preferably 40 kHz or less, preferably 15 kHz or more and 50 kHz or less, and more preferably 20 kHz or more and 40 kHz or less. [Frequency measurement method] Use a laser shift meter to measure the displacement of the front end of the horn. The frequency is measured by setting the sampling frequency to 200 kHz or more and the accuracy to 1 μm or more. In addition, from the viewpoint of easily forming a fusion portion and a through hole, the amplitude of the applied ultrasonic vibration is preferably 20 μm or more, more preferably 25 μm or more, and further preferably 50 μm or less, and more preferably 40 μm. Hereinafter, it is more preferably 20 μm or more and 50 μm or less, and more preferably 25 μm or more and 40 μm or less. [Measurement method of amplitude] Use a laser shift meter to measure the displacement of the horn tip. The amplitude was measured by setting the sampling frequency to 200 kHz or more and the accuracy to 1 μm or more. Next, the second and third embodiments of the method for producing a composite sheet of the present invention will be described. In the second embodiment, the above-mentioned composite sheet 10 is manufactured using the composite sheet manufacturing apparatus of the second embodiment showing the main part of FIG. 6. The manufacturing apparatus of the composite sheet of the second embodiment is only in the aspect of replacing the heater 61 (preheating mechanism) arranged in the first roller 31 with a mechanism for heating the ultrasonic welding head 42 of the ultrasonic fusion machine 41, It is different from the manufacturing apparatus 20 of the said composite sheet. More specifically, the apparatus for manufacturing a composite sheet according to the second embodiment includes a heater 62 mounted on the ultrasonic horn 42 as a mechanism for heating the ultrasonic horn 42. In the manufacturing method of the composite sheet of the second embodiment, by controlling the temperature of the ultrasonic horn 42 heated by the heater 62, the temperature of the second sheet 2 immediately before the application of ultrasonic vibration is heated in advance Under the condition that the melting point of the sheet 2 is less than 50 ° C lower than the melting point, in this state, it is sandwiched between the convex portion 35 of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine. The first and second sheets 1 and 2 are subjected to ultrasonic vibration. When the ultrasonic welding head 42 is heated by a heating mechanism such as a heater 62, in a state where ultrasonic vibration is applied by an ultrasonic fusion machine, the first and second sheets 1 and 2 generate heat and are difficult to measure. The temperature of the sheet heated by the preheating mechanism. Therefore, in the case where one or both of the first and second sheets 1 and 2 are preheated via the heated ultrasonic welding head 42, the ultrasonic vibration is not generated, and the measurement is performed only after heating for 30 minutes. The temperature of the front end 42t of the ultrasonic horn was set to the temperature of the sheet heated by the preheating mechanism. The points that are not particularly explained about the second embodiment are the same as those of the first embodiment, and the description about the first embodiment is appropriately applied. In the third embodiment, the above-mentioned composite sheet 10 is manufactured by using a manufacturing apparatus for a composite sheet according to the third embodiment, which shows the main part. The apparatus for manufacturing a composite sheet according to the third embodiment does not include a preheating mechanism for heating at least one of the first sheet and the second sheet to a specific temperature before applying ultrasonic vibration. On the other hand, Yu Chao A front end of the sonic horn 42 is provided with a heat storage member 7 (hereinafter also referred to as a "heat storage material"). In the manufacturing method of the third embodiment, the first sheet 1 is introduced into the engaging portion 33 of the first and second rollers 31 and 32 to be deformed into a concave-convex shape in the same manner as the manufacturing method of the first embodiment. After that, the first sheet 1 deformed into a concave-convex shape is conveyed toward the application unit 36 of the ultrasonic vibration while being held on the first roller 31, and the second sheet 2 is overlapped with the first sheet 1 being conveyed. The superimposed two sheets 1 and 2 are sandwiched between the convex portion 35 of the first roller 31 and the front end face 42t of the ultrasonic welding head 42 of the ultrasonic fusion machine, and an ultrasonic wave is applied to the ultrasonic vibration application portion 36. vibration. In the manufacturing method of the third embodiment, as shown in FIG. 7, the application of the ultrasonic vibration is performed in a state in which a heat storage material 7 is disposed at the front end of the ultrasonic horn 42. According to the manufacturing method of the third embodiment, the temperature of the front end of the ultrasonic welding head 42 including the heat storage material 7 is immediately after the operation of the manufacturing device of the composite sheet is at the temperature of the first and second sheets 1 and 2. Below the melting point, but if the operation continues, the heat of the first and second sheets 1 and 2 that are generated by ultrasonic vibration is accumulated in the heat storage material 7, and the temperature of the heat storage material 7 rises to become the first sheet 1 and the second The melting point of the sheet 2 or more. Then, in a state where the temperature of the heat storage material 7 is above the melting point of each of the first sheet 1 and the second sheet 2, the conditions when the ultrasonic vibration is applied, for example, the wavelength, intensity, When the sheets 1 and 2 are pressurized and the like, when the ultrasonic vibration is applied, the two sheets 1 and 2 are melted, and if the through holes 14 penetrating the two sheets 1 and 2 are formed to be surrounded by the molten portion, State, the fusion portion 4 having the through-holes 14 can be reliably formed, and troubles such as the adherence of the molten resin to the conveying mechanism or the winding of the sheet to the conveying roller caused by the melting of the sheet are not easy to occur, so the maintenance of the device The burden is also smaller. In addition, since the formation of the fusion portion 4 and the formation of the through hole 14 are performed simultaneously between the convex portion 35 of the first roller 31 and the ultrasonic welding head 42 of the ultrasonic fusion machine, the position and penetration of the fusion portion 4 are formed. There is no positional shift between the positions of the holes 14. The thermal storage material 7 has a lower thermal conductivity than a metal constituting at least the ultrasonic horn 42. The thermal storage material 7 preferably has a thermal conductivity measured by the following method of 2.0 W / mK or less. The thermal conductivity of the heat storage material is preferably 2.0 W / mK or less, more preferably 1.0 W / mK or less, from the viewpoint that it is not easy to radiate heat to the ultrasonic welding head or the atmosphere. From the viewpoint of efficiently heating the sheet, In particular, it is preferably 0.1 W / mK or more, more preferably 0.5 W / mK or more, and still more preferably 0.1 W / mK or more and 2.0 W / mK or less, more preferably 0.5 W / mK or more and 1.0 W / mK or less. [Method for Measuring Thermal Conductivity] The thermal conductivity of the heat storage material 7 is measured using a thermal conductivity measuring device. The heat storage material 7 is preferably one having heat resistance. The heat-resistant temperature of the heat storage material 7 is preferably 150 ° C or higher, more preferably 200 ° C or higher, and even more preferably 250 ° C or higher. There is no particular upper limit of the heat-resistant temperature, and it is, for example, 1500 ° C or lower. The heat storage material 7 may also include a body part having heat storage properties and an adhesive layer for adhering the body to an ultrasonic welding head. In this case, the thermal conductivity is measured by excluding the adhesive part. As the heat storage material, for example, commercially available products such as "glass cloth tape" manufactured by Nitto Denko and "polyimide tape for heat-resistant insulation" manufactured by Nitto Denko can also be used. Examples of the material of the heat storage material 7 having a heat storage body include glass, polyimide, and the like. From the viewpoint of having moderate heat storage and high heat resistance, polyimide and the like are preferred. The heat storage material 7 may be a single-layered sheet, or a laminated body such as two or more sheets including the same or different materials. The heat storage material 7 preferably has a shape that is longer in the same direction than the front end surface of the ultrasonic horn 42 that is longer in the axial length direction of the first roller 31. In addition, from the viewpoint of preventing seizure when the ultrasonic wave is applied, the heat storage material 7 is preferably as shown in FIG. 7. In addition to covering the front end face of the ultrasonic horn 42, it also has The portion of the corner portion 42a on the upstream side (left side in FIG. 7) of the sheet traveling direction of the end surface 42t is preferably the downstream side of the sheet traveling direction (the right side in FIG. 7) having the end surface 42t covering the front of the ultrasonic horn 42 Part of the corner portion 42b. Polyimide used in the body portion of the heat storage material 7 is also preferred in terms of excellent abrasion resistance and heat resistance, and is a synthetic resin that has the property of generating heat even when it receives ultrasonic vibration. From the same point of view, the synthetic resin layer 42h provided on the body portion of the thermal storage material 7 or the ultrasonic horn 42 shown in FIG. 8 (a) preferably includes polyimide or polybenzimidazole, poly Synthetic resins such as ether ethyl ketone, polyphenylene sulfide, polyetherimide, polyimide, imine, etc. with a Rockwell hardness of R120 or more and R140 or less, and a heat resistance temperature of 150 or more and 500 or less Including synthetic resins such as polyimide or polybenzimidazole with a Rockwell hardness of R125 or more and R140 or less, and a heat resistance temperature of 280 ° C or more and 400 ° C or less. Here, the Rockwell hardness is a value measured according to ASTM D785, and the heat resistance temperature is a value measured according to ASTM D648. The heat-resistant temperature of the synthetic resin layer provided at the front end of the ultrasonic horn 42 is preferably 150 ° C or higher, more preferably 280 ° C or higher, further preferably 500 ° C or lower, more preferably 400 ° C or lower, and The temperature is preferably 150 ° C or higher and 500 ° C or lower, and more preferably 280 ° C or higher and 400 ° C or lower. The Rockwell hardness of the synthetic resin layer provided at the front end of the ultrasonic horn 42 is preferably R120 or more, more preferably R125 or more, more preferably R140 or less, and still more preferably R120 or more and R140 or less. It is preferably R125 or more and R140 or less. Fig. 8 (a) is a view showing another example of the ultrasonic welding head 42 in which the heat storage material 7 is provided at the front end portion. In FIG. 8 (a), the circle C2 portion is an enlarged cross-sectional view of the circle C1 portion. In the ultrasonic welding head 42 shown in FIG. 8 (a), as shown in FIG. 8 (b), the front end face 42t of the body portion 42c of the ultrasonic welding head 42 including a metal such as an aluminum alloy or a titanium alloy. After forming a connecting layer 42f having a gap 42e from one surface 42d to the inside by thermal spraying, as shown in FIG. 8 (a), a synthetic resin layer as a member having heat storage properties is fixed on the side 42d of the connecting layer 42f. 42h. The so-called thermal spraying refers to a surface treatment method in which particles of a thermal spraying material such as metal or ceramic which is melted or nearly melted by heating are accelerated to collide with a substrate surface at a high speed, and a film is formed on the substrate surface. A synthetic resin layer 42h having a heat storage property is provided on the front end surface 42t of the main body portion 42c of the ultrasonic horn 42 including a metal such as titanium alloy through a connection layer 42f formed by thermal spraying. The material of the resin layer 42h is excellent in abrasion resistance and heat resistance. On the other hand, even in the case of using a synthetic resin such as polyimide, which is not easy to obtain sufficient fixing strength when directly fixed, it is also easy. Ground to obtain sufficient fixed strength. In addition, if the fixing strength is insufficient, defects such as peeling of the synthetic resin layer 42h are likely to occur during the production of the composite sheet 10. As the heat-spraying material used to form the connection layer 42f, those which can be heat-sprayed and can help improve the fixing strength of the synthetic resin layer 42h having heat storage properties can be used without particular limitation. From the viewpoint of excellent bonding strength of the body portion 42c of the ultrasonic horn 42 and excellent wear resistance or heat resistance, ceramics such as tungsten carbide, zirconia, and chromium carbide, aluminum magnesium, zinc aluminum, and the like are preferably used. Metals such as alloys, aluminum, stainless steel, titanium, molybdenum, and cermets as composite materials of metals and ceramics are more preferably ceramics from the viewpoint of forming voids 42e that improve the fixed strength of the synthetic resin layer 42h. To use tungsten carbide. In addition, the forming material of the connecting layer 42f has a higher melting point than the synthetic resin constituting the synthetic resin layer 42h having heat storage properties, and maintains the shape of the void 42e when the synthetic resin 42h is formed. From the viewpoint of improving the fixing strength of the synthetic resin layer 42h It ’s better. Examples of the method for fixing the synthetic resin layer 42h having heat storage property to the connecting layer 42f include a method of dipping the connecting layer 42f in a synthetic resin melted by heating; and applying a synthetic resin melted by heating to A method for connecting the layer 42f; a method for pressing the plate-shaped body of the softened synthetic resin against the connection layer 42f; The thickness Tf of the connecting layer 42f [see FIG. 8 (a)] is not particularly limited. If an example is given, it is preferably 10 μm or more, more preferably 20 μm or more, and further preferably 100 μm or less, and more preferably 50 μm. μm or less, more preferably 10 μm or more and 100 μm or less, and more preferably 20 μm or more and 50 μm or less. The thickness Th of the synthetic resin layer 42h having heat storage properties [refer to FIG. 8 (a)] is not particularly limited. If an example is given, it is preferably 5 μm or more, more preferably 10 μm or more, and still more preferably 100 μm or less. , More preferably 50 μm or less, more preferably 5 μm or more and 100 μm or less, and even more preferably 10 μm or more and 50 μm or less. In addition, the ratio of the thickness Tf of the connection layer 42f to the total thickness Tt of the thickness Tf and the thickness Th of the synthetic resin layer 42h is preferable from the viewpoint of maintaining the fixed strength of the synthetic resin and not hindering ultrasonic vibration or heat generation. 30% or more, more preferably 50% or more, more preferably 85% or less, more preferably 75% or less, still more preferably 30% or more and 85% or less, more preferably 50% or more and 75% or more the following. Even if it is a manufacturing apparatus of a composite sheet having a heat storage material 7 like the third embodiment, it may have a preheating mechanism 6 provided in the manufacturing apparatus of the composite sheet of the first embodiment or a composite sheet of the second embodiment. A mechanism for heating the ultrasonic welding head 42 provided in the material manufacturing apparatus. It is preferable that the composite sheet 10 manufactured in each said embodiment has the following structures. The height H (see FIG. 1) of the convex portion 5 is 1 to 10 mm, and particularly preferably 3 to 6 mm. Composite sheet 10 per unit area (1 cm ² The number of convex portions 5) is 1-20, and particularly preferably 6-15. The bottom dimension A (see FIG. 1) of the convex portion 5 in the X direction is 0.5 to 5.0 mm, and particularly preferably 1.0 to 4.0 mm. The bottom dimension B (see FIG. 1) of the convex portion 5 in the Y direction is 1.0 to 10 mm, and particularly preferably 2.0 to 7.0 mm. The ratio of the bottom dimension A in the X direction to the bottom dimension B in the Y direction (bottom dimension A: bottom dimension B) is 1: 1 to 1:10, particularly preferably 1: 2 to 2: 5. The bottom area (bottom size A × bottom size B) of the protrusion 5 is 0.5 to 50 mm ² , Especially good for 2 ～ 20 mm ² . The size C (see FIG. 1) of the fusion zone 4 in the X direction is 0.5 to 2 mm, particularly preferably 0.8 to 1.5 mm, and the size D (see FIG. 1) in the Y direction is 1.0 to 5.0 mm, and particularly preferably 1.2 to 3.0. mm. The ratio of the dimension C in the X direction to the dimension D in the Y direction (dimension C: dimension D) is 1: 1 to 1: 3, particularly preferably 2: 3 to 2: 5. The inner area of the fusion portion 4 from the outer periphery is preferably 0.5 mm ² Above, more preferably 1.0 mm ² Above, again, preferably 5.0 mm ² Below, more preferably 4.0 mm ² Below, again, preferably 0.5 mm ² Above 5.0 mm ² Below, more preferably 1.0 mm ² Above 4.0 mm ² the following. The area on the inner side of the fusion portion 4 from the outer periphery also includes the area of the through hole 14. The opening area of the through hole 14 is preferably 50% or more, more preferably 80% or more, and more preferably less than 100%, and more preferably 95% or less with respect to the area on the inner side of the fusion portion 4 than the outer periphery. Moreover, it is preferably 50% or more and 100% or less, and more preferably 80% or more and 95% or less. The above-mentioned composite sheet 10 is preferably used as a surface sheet of absorbent articles such as disposable diapers, menstrual tampons, sanitary pads, incontinence pads and the like. Moreover, it can also be used for applications other than the surface sheet of an absorbent article. For example, as a sheet for an absorbent article, a sheet disposed between a surface sheet and an absorbent body, a sheet for forming a three-dimensional wrinkle (leak-proof wall) (particularly a sheet forming an inner wall of a wrinkle) can be used. ), Etc., and for applications other than absorbent articles, it can be used as a cleaning sheet, especially a cleaning sheet mainly for liquid absorption, or a cosmetic sheet for humans. When it is used for cleaning a sheet, the convex part has a good followability to a non-smooth surface to be cleaned. Therefore, it is preferable to use the first nonwoven fabric side toward the surface to be cleaned. When it is used as a cosmetic sheet, it can follow the skin of the subject in the convex part, and it can show the massage effect, and it can absorb excess makeup (other use) or sweat, so it is better to use the first non-woven fabric. Use with the side facing the skin. The manufacturing method and manufacturing apparatus of the composite sheet of the present invention are not limited in any way by the foregoing embodiments, and can be appropriately modified. For example, the above-mentioned composite sheet 10 is formed with one fused portion in each recessed portion, but the composite sheet manufactured in the present invention may also include a plurality of fused portions in one recessed portion. Moreover, although the convex part 5 of the composite sheet 10 is a quadrangular frustum shape, it may be a hemispherical shape or the like. Moreover, the extent to which the convex portion 5 and the fusion portion 4 in the mutually adjacent rows are shifted in the X direction may replace the ½ pitch, 1/3 pitch, 1/4 pitch, etc., and may not be in the X direction. Offset. In addition, the plan view shapes of the fused portion and the through hole may be oval, circular, polygonal (corner, rectangle, triangle, diamond, etc.) with rounded corners. In addition, the manufactured composite sheet 10 may be one in which convex portions and fusion portions are formed as shown in FIG. 4 or FIG. 5 of Japanese Patent Laid-Open No. 2016-116582, or Japanese Patent Laid-Open No. 2016-116583 In the aspect shown in FIG. 3 of the publication, a convex portion and a fused portion are formed. In addition, instead of setting all of the fused portions of the composite sheet as a fused portion having a through hole, one of the fused portions of the composite sheet may be a fused portion with a through hole. For example, one or both of the first and second sheets in the central region in the width direction of the band-shaped composite sheet may be preheated to form a fusion portion having a through hole. Preheating is performed across both the first and second sheets in the side region of the center region to form a fused portion without a through hole. Regarding the embodiment (aspect) of the present invention described above, the following method for manufacturing a composite sheet and a device for manufacturing a composite sheet will be disclosed. <1> A method for manufacturing a composite sheet, the composite sheet having a plurality of fused portions where the first sheet and the second sheet are fused, and at least a part of the first sheet except for the fused portion A method of manufacturing a composite sheet is provided by forming a convex portion protruding to the side opposite to the second sheet side. The forming step includes rotating a first roll and a second roll that have irregularities that engage with each other on the peripheral surface. , While introducing the first sheet to the engaging portions of the two rolls to deform it into a concave-convex shape; in the overlapping step, the first sheet deformed into the concave-convex shape is held on the first roll while being conveyed And superimposing the second sheet on the first sheet during transportation; and an ultrasonic processing step of sandwiching the two overlapping sheets between the convex portion of the first roller and the ultrasonic wave of the ultrasonic fusion machine Ultrasonic vibration is applied between the welding heads; in the above-mentioned ultrasonic processing step, when the ultrasonic vibration is applied, the fusion portion having a through hole is formed. <2> The method for manufacturing a composite sheet according to the above <1>, wherein the ultrasonic welding head is heated to a specific temperature, and in the ultrasonic processing step, the first sheet is heated together with the application of the ultrasonic vibration And at least one of the second sheet. <3> The method for producing a composite sheet according to <1> or <2>, wherein the first roll is heated to a specific temperature, and the first sheet and the first sheet are heated in advance before the ultrasonic vibration is applied. At least one of 2 sheets. <4> The method for producing a composite sheet according to any one of <1> to <3>, wherein at least one of the first sheet and the second sheet is applied before the ultrasonic vibration is applied. Directly preheat to a specific temperature. <5> The method for producing a composite sheet according to any one of the above <2> to <4>, wherein the specific temperature does not reach the melting point of the first sheet or the second sheet, which is lower than the melting point, Above 50 ° C. <6> The method for producing a composite sheet according to any one of <1> to <5>, wherein in the above-mentioned ultrasonic processing step, a member having heat storage properties is arranged at an end portion before the above-mentioned ultrasonic welding head. The above-mentioned application of the ultrasonic vibration is performed in a state of, and when the ultrasonic vibration is applied, the fused portion having a through hole is formed. <7> The method for manufacturing a composite sheet according to the above <6>, wherein the thermal storage member has a lower thermal conductivity than a material constituting the ultrasonic horn. <8> The method for producing a composite sheet according to the above <6> or <7>, wherein the thermal conductivity of the heat storage member is 2.0 W / mK or less, preferably 1.0 W / mK or less. 0.1 W / mK or more, preferably 0.5 W / mK or more, and 0.1 W / mK or more and 2.0 W / mK or less, preferably 0.5 W / mK or more and 1.0 W / mK or less. <9> The method for producing a composite sheet according to any one of <6> to <8>, wherein the heat storage member has heat resistance, and the heat storage member has a heat resistance temperature of 150 ° C or higher, The temperature is preferably 200 ° C. or higher, more preferably 250 ° C. or higher, and the upper limit of the heat-resistant temperature of the heat storage member is 1500 ° C. or lower. <10> The method for producing a composite sheet according to any one of the above <6> to <9>, wherein the material of the heat storage member is glass or polyimide. <11> The method for manufacturing a composite sheet according to any one of the above <6> to <10>, wherein the member having heat storage properties has a function of covering the ultrasonic wave in addition to a portion covering the front end face of the ultrasonic horn. The portion of the corner on the upstream side of the sheet on the front face of the horn. <12> The method for manufacturing a composite sheet according to the above <11>, wherein the member having heat storage properties further has a corner portion covering a downstream side of the sheet in the direction of travel of the sheet on the front end face of the ultrasonic horn. <13> The method for manufacturing a composite sheet according to any one of the above <1> to <12>, wherein the first end face of the first roller and the front end face of the ultrasonic welding head are sandwiched between the first end face of the ultrasonic welding head and the first end face. The pressure applied by one sheet and the second sheet is 10 N / mm or more, preferably 15 N / mm or more, and 150 N / mm or less, and preferably 120 N / mm or less. 10 N / mm or more and 150 N / mm or less, preferably 15 N / mm or more and 120 N / mm or less. <14> The method for manufacturing a composite sheet according to any one of the above <1> to <13>, wherein the frequency of the above-mentioned ultrasonic vibration is 15 kHz or more, preferably 20 kHz or more, and 50 kHz Hereinafter, it is preferably 40 kHz or less, and 15 kHz or more and 50 kHz or less, and more preferably 20 kHz or more and 40 kHz or less. <15> The method for producing a composite sheet according to any one of the above <1> to <14>, wherein the amplitude of the ultrasonic vibration applied is 20 μm or more, preferably 25 μm or more, and 50 μm Hereinafter, it is preferably 40 μm or less, and more preferably 20 μm or more and 50 μm or less, and more preferably 25 μm or more and 40 μm or less. <16> The method for manufacturing a composite sheet according to any one of the above <1> to <15>, wherein the composite sheet is used as an absorbent article such as disposable diapers, menstrual cotton, sanitary pads, incontinence pads, etc. Surface sheet. <17> An apparatus for manufacturing a composite sheet, the composite sheet having a plurality of fused portions where the first sheet and the second sheet are fused, and at least a part of the first sheet except for the fused portion A convex portion protruding toward the opposite side to the second sheet side is formed, and the manufacturing apparatus of the composite sheet includes: a concave-convex forming portion having a first roller and a second roller having irregularities that mesh with each other on a peripheral surface portion, And deforming the first sheet introduced into the meshing portion of the two rolls into a concave-convex shape; and an ultrasonic processing section including an ultrasonic fusion machine, and superimposing the second sheet on the deformed concave-convex shape After the state of the first sheet, the two sheets are sandwiched between the convex portion of the first roller and the ultrasonic welding head of the ultrasonic fusion machine to locally apply ultrasonic vibration to form a through hole. The above-mentioned fusion portion of the hole. <18> The apparatus for manufacturing a composite sheet according to the above <17>, which includes a mechanism for heating the ultrasonic horn. <19> The device for manufacturing a composite sheet according to the above <17> or <18>, which includes a preheating mechanism that applies the first sheet and the second sheet before the ultrasonic vibration is applied. At least one is preheated to a specific temperature. <20> The device for manufacturing a composite sheet according to the above <19>, wherein the preheating mechanism is a heater arranged in the first roller. <21> The device for manufacturing a composite sheet according to the above <19> or <20>, wherein the first sheet is heated to a temperature lower than the melting point of the sheet and lower than the melting point by the preheating mechanism. Above 50 ° C. <22> The manufacturing apparatus for a composite sheet according to any one of the above <19> to <21>, wherein the preheating mechanism is used to preheat to a temperature 20 ° C or lower than the melting point of the first sheet. And below 5 ° C below the melting point. <23> The apparatus for producing a composite sheet according to any one of the items <17> to <22>, wherein a member having a heat storage property is arranged at the front end portion of the ultrasonic horn. <24> The device for manufacturing a composite sheet according to the above <23>, wherein the heat storage member has a lower thermal conductivity than a material constituting the ultrasonic horn. <25> The device for manufacturing a composite sheet according to the above <23> or <24>, wherein the thermal conductivity of the heat storage member is 2.0 W / mK or less, preferably 1.0 W / mK or less, and is 0.1 W / mK or more, preferably 0.5 W / mK or more, and 0.1 W / mK or more and 2.0 W / mK or less, preferably 0.5 W / mK or more and 1.0 W / mK or less. <26> The device for manufacturing a composite sheet according to any one of the above <23> to <25>, wherein the heat storage member has heat resistance, and the heat storage member has a heat resistance temperature of 150 ° C or higher, The temperature is preferably 200 ° C. or higher, more preferably 250 ° C. or higher, and the upper limit of the heat-resistant temperature of the heat storage member is 1500 ° C. or lower. <27> The device for manufacturing a composite sheet according to any one of the above <23> to <26>, wherein the member having heat storage properties has a coating on the ultrasonic wave in addition to a portion covering the front end face of the ultrasonic horn. The portion of the corner on the upstream side of the sheet on the front face of the horn. <28> The device for manufacturing a composite sheet according to the above <27>, wherein the heat storage member further has a corner portion covering the downstream side of the sheet in the direction of travel of the sheet on the front end face of the ultrasonic horn. <29> The device for producing a composite sheet according to any one of the above <23> to <28>, wherein the material of the heat storage member is glass or polyimide. <30> The apparatus for manufacturing a composite sheet according to any one of the items <23> to <29>, in which a heat-resistant synthetic resin is provided as a member having heat storage property at the front end of the ultrasonic horn. Floor. <31> The device for manufacturing a composite sheet according to the above <30>, wherein the heat-resistant temperature of the synthetic resin layer is 150 ° C or higher, preferably 280 ° C or higher, and 500 ° C or lower, preferably 400 ° C or lower, The temperature is 150 ° C or higher and 500 ° C or lower, preferably 280 ° C or higher and 400 ° C or lower. <32> The device for manufacturing a composite sheet according to any one of the items <23> to <31>, wherein the front end portion of the ultrasonic horn is provided with a wear-resistant member as a member having heat storage properties. Synthetic resin layer. <33> The device for manufacturing a composite sheet according to the above <32>, wherein the Rockwell hardness of the synthetic resin layer is R120 or more, preferably R125 or more, and R140 or less, and R120 or more and R140 or less, It is preferably R125 or more and R140 or less. <34> The apparatus for producing a composite sheet according to any one of the items <30> to <33>, wherein the synthetic resin layer is fixed to the ultrasonic welding head through a connection layer formed by thermal spraying. Front end face of metal body part. <35> The apparatus for manufacturing a composite sheet according to any one of <17> to <34>, wherein the first sheet and the first sheet are sandwiched between the convex portion of the first roller and the ultrasonic welding head. The pressure applied by the second sheet is 10 N / mm or more, preferably 15 N / mm or more, 150 N / mm or less, preferably 120 N / mm or less, and 10 N / mm. Above 150 N / mm, preferably above 15 N / mm and below 120 N / mm. <36> The device for manufacturing a composite sheet according to any one of the above <17> to <35>, wherein the frequency of the above-mentioned ultrasonic vibration is 15 kHz or more, preferably 20 kHz or more, and 50 kHz Hereinafter, it is preferably 40 kHz or less, and 15 kHz or more and 50 kHz or less, and more preferably 20 kHz or more and 40 kHz or less. <37> The device for manufacturing a composite sheet according to any one of <17> to <36>, wherein the amplitude of the ultrasonic vibration applied is 20 μm or more, preferably 25 μm or more, and 50 μm or less It is preferably 40 μm or less, more preferably 20 μm or more and 50 μm or less, and more preferably 25 μm or more and 40 μm or less. <38> The device for manufacturing a composite sheet according to any one of the above <17> to <37>, wherein the composite sheet is used as an absorbent article such as disposable diapers, menstrual cotton, sanitary pads, incontinence pads, etc. Surface sheet. [Industrial Applicability] According to the manufacturing method of the composite sheet of the present invention, a fused portion having a through hole can be easily formed, and a positional deviation is not easily generated between the position of the fused portion and the position of the through hole. The maintenance burden is also small. According to the manufacturing device of the composite sheet of the present invention, a fusion portion having a through hole can be easily formed, and a positional displacement is not easily generated between the position of the fusion portion and the position of the through hole, and the maintenance burden of the device is also small.

1‧‧‧ the first sheet

2‧‧‧ 2nd sheet

3‧‧‧ recess

4‧‧‧ fusion section

5‧‧‧ convex

6‧‧‧preheating mechanism

7‧‧‧ heat storage material

10‧‧‧ composite sheet

14‧‧‧through hole

20‧‧‧Manufacturing equipment

30‧‧‧ Bump forming section

31‧‧‧Roll 1

31a, 31b‧‧‧‧Spur gear

32‧‧‧ 2nd roller

33‧‧‧ meshing part

34‧‧‧ Suction hole

35‧‧‧ convex

35c‧‧‧ convex 35 front face

36‧‧‧ Application Department

40‧‧‧ Ultrasonic Processing Department

41‧‧‧ Ultrasonic fusion machine

42‧‧‧ Ultrasonic Welding Head

42a‧‧‧Corner

42b‧‧‧ Corner

42c‧‧‧Body

42d‧‧‧ side

42e‧‧‧Gap

42f‧‧‧ Connection layer

42h‧‧‧Synthetic resin layer

42t‧‧‧ Ultrasonic Welding Head

43‧‧‧ converter

44‧‧‧ accelerator

45‧‧‧ movable table

61‧‧‧heater

62‧‧‧heater

A‧‧‧ Bottom dimension of X direction of convex part 5

B‧‧‧ Bottom dimension of Y direction of convex part 5

C‧‧‧X dimension

C1‧‧‧circle

C2‧‧‧circle

D‧‧‧Y dimension

G‧‧‧Gap

Tf‧‧‧ thickness of connecting layer 42f

Thickness of Th‧‧‧ synthetic resin layer 42h

Tt‧‧‧Total thickness

FIG. 1 is a perspective view of main parts showing an example of a composite sheet manufactured by the method and apparatus for manufacturing a composite sheet of the present invention. FIG. 2 is an enlarged plan view of the composite sheet shown in FIG. 1 as viewed from the first sheet side. Fig. 3 is a schematic view showing a first embodiment of a method for manufacturing a composite sheet of the present invention and a first embodiment of a device for manufacturing a composite sheet of the present invention. FIG. 4 is an enlarged perspective view showing a main part of the first roller shown in FIG. 3. FIG. 5 is a diagram showing a main part of the ultrasonic welding machine shown in FIG. 3 and a diagram showing a state viewed from the left side in FIG. 3. FIG. 6 is a diagram showing the main parts of the second embodiment of the method for manufacturing a composite sheet of the present invention and the second embodiment of the device for manufacturing a composite sheet of the present invention. FIG. 7 is a view showing a main part of a third embodiment of the method for manufacturing a composite sheet according to the present invention and the third embodiment of the device for manufacturing a composite sheet according to the present invention. Fig. 8 (a) is a view showing another example of an ultrasonic welding head provided with a synthetic resin layer having a heat storage property at a tip portion, and Fig. 8 (b) is a view showing a body of an ultrasonic welding head including a metal such as titanium alloy. A part of the front end surface is formed by a thermal spray to form only the connection layer.

Claims (38)

A method for manufacturing a composite sheet, the composite sheet having a plurality of fused portions where a first sheet and a second sheet are fused, and at least a part of the first sheet except for the fused portion is formed to be opposite to The second sheet side is a convex portion protruding on the opposite side. The manufacturing method of the composite sheet includes: a forming step of rotating the first roller and the second roller that have irregularities that engage with each other on the peripheral surface, and The first sheet is introduced into the meshing portion of the two rollers to deform it into a concave-convex shape; in the overlapping step, the first sheet deformed into the concave-convex shape is transported while holding the first sheet on the first roller, and The second sheet is superimposed on the first sheet being transported; and an ultrasonic processing step of sandwiching the two overlapped sheets between the convex portion of the first roller and the ultrasonic welding head of the ultrasonic fusion machine. In the above ultrasonic processing step, when the ultrasonic vibration is applied, the fused portion having a through hole is formed. For example, the method for manufacturing a composite sheet according to claim 1, wherein the ultrasonic horn is heated to a specific temperature, and in the ultrasonic processing step, the first sheet and the first sheet are heated together with the application of the ultrasonic vibration. At least one of 2 sheets. For example, the method for manufacturing a composite sheet according to claim 1, wherein the first roll is heated to a specific temperature, and at least one of the first sheet and the second sheet is heated in advance before the ultrasonic vibration is applied. For example, the method for manufacturing a composite sheet according to claim 1, wherein at least one of the first sheet and the second sheet is directly heated in advance to a specific temperature before the ultrasonic vibration is applied. For example, the method for manufacturing a composite sheet according to claim 2, wherein the specific temperature is the melting point of the above-mentioned first sheet or the above-mentioned second sheet, which is not higher than the melting point by 50 ° C or more. For example, the method for manufacturing a composite sheet according to claim 1, wherein in the above-mentioned ultrasonic processing step, the application of the above-mentioned ultrasonic vibration is performed in a state where a member having a heat storage property is arranged at the front end of the above-mentioned ultrasonic welding head, in When the ultrasonic vibration is applied, the fused portion having a through hole is formed. For example, the method for manufacturing a composite sheet according to claim 6, wherein the thermal storage member has a lower thermal conductivity than the material constituting the ultrasonic horn. The method for manufacturing a composite sheet according to claim 6, wherein the thermal conductivity of the above-mentioned member having thermal storage properties is 0.1 W / mK or more and 2.0 W / mK or less. The method for manufacturing a composite sheet according to claim 6, wherein the heat storage member has heat resistance, and the heat storage member has a heat resistance temperature of 150 ° C to 1500 ° C. The method for manufacturing a composite sheet according to claim 6, wherein the material of the heat storage member is glass or polyimide. For example, the method for manufacturing a composite sheet according to claim 6, wherein in addition to the part having the heat storage property covering the part of the front end face of the ultrasonic horn, the member having the upstream side of the sheet traveling direction covering the front end face of the ultrasonic horn is also provided. Corner section. The method for manufacturing a composite sheet according to claim 11, wherein the member having heat storage properties further has a portion covering a corner portion on a downstream side of a sheet in a traveling direction of the front end face of the ultrasonic horn. For example, the method for manufacturing a composite sheet according to claim 1, wherein the first sheet and the second sheet are added between the front end surface of the convex portion of the first roller and the front end surface of the ultrasonic horn. The pressure is 10 N / mm or more and 150 N / mm or less. The method for manufacturing a composite sheet according to claim 1, wherein the frequency of the above-mentioned ultrasonic vibration is 15 kHz or more and 50 kHz or less. For example, the method for manufacturing a composite sheet according to claim 1, wherein the amplitude of the above-mentioned ultrasonic vibration is 20 μm or more and 50 μm or less. For example, the method for manufacturing a composite sheet according to claim 1, wherein the composite sheet is used as a surface sheet for absorbent articles such as disposable diapers, menstrual tampons, sanitary pads, and incontinence pads. An apparatus for manufacturing a composite sheet, the composite sheet having a plurality of fusion portions where a first sheet and a second sheet are fused, and at least a part of the first sheet except for the fusion portion is formed to be opposite to The second sheet side is a convex portion protruding on the opposite side, and the manufacturing apparatus of the composite sheet includes: a concave-convex forming portion having a first roller and a second roller that have convex and concave portions that mesh with each other on a peripheral surface portion, and is introduced. The above-mentioned first sheet to the meshing portion of the two rollers is deformed into a concave-convex shape; and the ultrasonic processing unit is provided with an ultrasonic fusion machine, and the above-mentioned second sheet is superimposed on the state deformed into an uneven shape. After the first sheet is placed, the two sheets are sandwiched between the convex portion of the first roll and the ultrasonic welding head of the ultrasonic fusion machine to locally apply ultrasonic vibration to form the above-mentioned through hole. Fusion section. The apparatus for manufacturing a composite sheet according to claim 17, further comprising a mechanism for heating the ultrasonic welding head. For example, the device for manufacturing a composite sheet according to claim 17 includes a preheating mechanism that preheats at least one of the first sheet and the second sheet before applying the ultrasonic vibration to a specific temperature. . The device for manufacturing a composite sheet according to claim 19, wherein the preheating mechanism is a heater arranged in the first roller. For example, the device for manufacturing a composite sheet according to claim 19, wherein the first sheet is heated to a temperature not higher than the melting point of the sheet and 50 ° C lower than the melting point by the preheating mechanism. For example, the device for manufacturing a composite sheet according to claim 19, wherein the preheating mechanism is used to preheat to a temperature 20 ° C lower than the melting point of the first sheet and 5 ° C lower than the melting point. The manufacturing apparatus of the composite sheet according to claim 17, wherein a member having a heat storage property is arranged at the front end portion of the ultrasonic horn. For example, the device for manufacturing a composite sheet according to claim 23, wherein the thermal storage member has a lower thermal conductivity than the material constituting the ultrasonic horn. For example, the device for manufacturing a composite sheet according to claim 23, wherein the thermal conductivity of the above-mentioned member having a heat storage property is 0.1 W / mK or more and 2.0 W / mK or less. The manufacturing apparatus of the composite sheet according to claim 23, wherein the heat storage member has heat resistance, and the heat storage member has a heat resistance temperature of 150 ° C or more and 1500 ° C or less. For example, the device for manufacturing a composite sheet according to claim 23, wherein in addition to a part covering the front end face of the ultrasonic horn, the member having heat storage properties further includes a sheet on the upstream side of the direction of travel of the sheet covering the front end face of the ultrasonic horn. Corner section. The apparatus for manufacturing a composite sheet according to claim 27, wherein the member having heat storage properties further has a portion covering a corner portion on the downstream side of the sheet in the traveling direction of the front end face of the ultrasonic horn. The device for manufacturing a composite sheet according to claim 23, wherein the material of the heat storage member is glass or polyimide. The manufacturing apparatus of the composite sheet according to claim 23, wherein a heat-resistant synthetic resin layer is provided as a member having heat storage property at the front end of the ultrasonic horn. The apparatus for manufacturing a composite sheet according to claim 30, wherein the heat-resistant temperature of the synthetic resin layer is 150 ° C or higher and 500 ° C or lower. The manufacturing apparatus of the composite sheet according to claim 23, wherein a synthetic resin layer having abrasion resistance is provided as a member having heat storage property at the front end portion of the ultrasonic horn. The device for manufacturing a composite sheet according to claim 32, wherein the Rockwell hardness of the synthetic resin layer is R120 or more and R140 or less. For example, the device for manufacturing a composite sheet according to claim 30, wherein the synthetic resin layer is fixed to the front end face of the metal-containing body portion of the ultrasonic horn via a connection layer formed by thermal spraying. For example, the device for manufacturing a composite sheet according to claim 17, wherein the pressing force applied to the first sheet and the second sheet is sandwiched between the convex portion of the first roller and the ultrasonic welding head, and the pressure is 10 N. / mm to 150 N / mm. For example, the device for manufacturing a composite sheet according to claim 17, wherein the frequency of the above-mentioned ultrasonic vibration is 15 kHz or more and 50 kHz or less. For example, the apparatus for manufacturing a composite sheet according to claim 17, wherein the amplitude of the above-mentioned ultrasonic vibration is 20 μm or more and 50 μm or less. For example, the device for manufacturing a composite sheet according to claim 17, wherein the composite sheet is used as a surface sheet for absorbent articles such as disposable diapers, menstrual tampons, sanitary pads, and incontinence pads.