Abstract:
An absorbent article having a napkin body ( 2 ) comprising as the essentials a liquid-permeable top sheet ( 3 ), a liquid-impermeable back sheet ( 4 ), and a liquid-absorbing member ( 5 ) placed between the top sheet ( 3 ) and the back sheet ( 4 ), wherein a removable cover sheet ( 20 A) having a length and a width which do not exceed respectively the length and width of the napkin body ( 2 ) is provided on the top sheet ( 3 ) side of the napkin body ( 2 ) in contact with the top sheet ( 3 ).

Description:
REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a national stage application under 35 USC 371 of International Application No. PCT/JP2009/051307, filed Jan. 28, 2009, which claims the priority of Japanese Application No. 2008-016469, filed Jan. 28, 2008, the contents of which prior applications are incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to absorbent articles, such as a sanitary napkin, a liner, and an incontinence pad, which are pasted to undergarment for use. 
       BACKGROUND OF THE INVENTION 
       [0003]    Patent Document 1 discloses a first conventional example of a sanitary napkin, which is an absorbent article. As shown in  FIGS. 14(   a ), and ( b ), the sanitary napkin  100  of this first conventional example includes an napkin main body  101 , which is an absorbent main body, and a cover sheet  110  detachable from the napkin main body  101 . The napkin main body  101  includes a liquid-permeable topsheet  102 , a liquid-impermeable backsheet  103 , and an absorber  104 . The absorber  104  is disposed between the topsheet  102  and the backsheet  103 , and configured to absorb liquid. Outer peripheries of the topsheet  102  and the backsheet  103  are bonded to each other by means of a hot-melt-bonded portion  105  (shown in  FIG. 14(   a ) by the cross hatching). Adhesive portions  106  are provided onto an outer surface of the backsheet  103 . A release sheet  107  is bonded to outer surfaces of the adhesive portions  106 . 
         [0004]    The cover sheet  110  is disposed on a surface of the topsheet  102 . The cover sheet  110  is temporarily attached to the napkin main body  101  by means of a hot-melt-bonded portion  111  disposed on a portion of the topsheet  102 . 
         [0005]    Next, brief description is given of a mounting procedure of the sanitary napkin  100 . First, the release sheet  107  is peeled off. Next, the napkin main body  101  with the cover sheet  110  attached thereto is positioned at an appropriate position of undergarment. The positioned napkin main body  101  with the cover sheet  110  attached thereto is pressed to the undergarment with the fingers or the palms. The napkin main body  101  with the cover sheet  110  attached thereto is pasted to the undergarment by means of the adhesive portions  106 . Next, the cover sheet  110  is detached from the napkin main body  101  to complete the mounting. 
         [0006]    Patent Document 2 discloses a second conventional example of a sanitary napkin. As shown in  FIGS. 15(   a ) and ( b ), a sanitary napkin  120  according to this second conventional example includes a napkin main body  121 , which is an absorbent main body, and a cover sheet  130  detachable from the napkin main body  121 . The napkin main body  121  includes a liquid-permeable topsheet  122 , a liquid-impermeable backsheet  123 , an absorber  124  configured to absorb liquid, and a pair of wings  125 . The absorber  124  is disposed between the topsheet  122  and the backsheet  123 . The pair of wings  125  project in width directions from outer edges of the topsheet  122  and the backsheet  123  extending in a longitudinal direction. 
         [0007]    The outer edges of the topsheet  122  and the backsheet  123  are bonded to each other by means of a hot-melt-bonded portion  126  (shown in  FIG. 15(   a ) by the cross hatching). An adhesive portion  127  is provided on an outer surface of the backsheet  123 . A release sheet  128  is bonded to an outer surface of the adhesive portion  127 . The pair of wings  125  are folded back on a top surface of the topsheet  122 . Adhesive portions  129  are provided onto outer surfaces of the wings  125  in the folded state, respectively. 
         [0008]    The cover sheet  130  is placed on an upper side of the pair of wings  125  and covers a surface of the napkin main body  121  on which the topsheet  122  exists. The cover sheet  130  is temporarily attached to the napkin main body  121  by means of the adhesive portions  129  provided to the pair of wings  125 . 
         [0009]    Next, brief description is given of a mounting procedure of the sanitary napkin  120 . First, the release sheet  128  is peeled off from the napkin main body  121 . Next, the napkin main body  121  with the cover sheet  130  attached thereto is positioned at an appropriate position of undergarment. The positioned napkin main body  121  with the cover sheet  130  attached thereto is pressed to the undergarment with the fingers or the palms. The napkin main body  121  with the cover sheet  130  attached thereto is pasted to the undergarment by means of the adhesive portion  127 . Next, the cover sheet  130  is detached from the napkin main body  121 . Then, the wings  125  are folded back around lateral edges of a crotch portion of the undergarment. The wings  125  thus folded are pressed to the undergarment with the fingers or the palms. The wings  125  are pasted to the undergarment by means of the adhesive portions  129 . 
         [0000]    Patent Document 1: Japanese Patent Application Publication No. Hei 8-56989 
       Patent Document 2: Japanese Patent Application Publication No. 2005-58783   
     SUMMARY OF THE INVENTION 
       [0010]    In the sanitary napkin  100  of the first conventional example, the dimensions of the cover sheet  110  in the longitudinal direction and in the width direction are larger than the dimensions of the napkin main body  101  in the longitudinal direction and in the width direction, respectively. This prevents the user from visually observing the contour of the napkin main body  101  during the positioning of the napkin main body  101  with respect to undergarment. For this reason, it is difficult to position the napkin main body  101  at an appropriate position of the undergarment. 
         [0011]    Meanwhile, in the sanitary napkin  120  of the second conventional example, the dimensions of the napkin main body  121  in the longitudinal direction and in the width direction are smaller than the dimensions of the cover sheet  130  in the longitudinal direction and in the width direction, respectively. Accordingly, the user can visually observe the contour of the napkin main body  121  during the positioning of the napkin main body  121  with respect to undergarment. Accordingly, the sanitary napkin  120  does not have the disadvantage as in the case of the first conventional example. However, the sanitary napkin  120  of the second conventional example necessitates detaching the cover sheet  130  from the napkin main body  121  before the folding of the wings  125 . For this reason, when the user pastes the wings  125  to undergarment, the fingers or the palms of the user may come into contact with the topsheet  122 . Accordingly, soil, bacteria, and the like on the fingers or the palms of the user may be attached to the topsheet  122 , and thus the topsheet  122  cannot be kept clean. 
         [0012]    In this respect, an object of the present invention is to provide an absorbent article which enables an absorbent main body to be easily positioned at an appropriate position of undergarment, and which also enables a topsheet to be kept clean during the mounting process. 
         [0013]    To achieve the above object, the invention according to claim  1 , an absorbent article including an absorbent main body formed at least of a liquid-permeable topsheet configured to come into contact with a skin of a wearer and a liquid-impermeable backsheet configured to come into contact with clothing, the absorbent article includes: a cover sheet covering the topsheet, wherein the cover sheet is in contact with a contact surface of the topsheet at which the topsheet and an excretion portion of the wearer are to be in contact with each other, and both ends of the cover sheet in a longitudinal direction at least partially coincide with or recede from both ends of the absorbent main body in the longitudinal direction, and both ends of the cover sheet in a width direction at least partially coincide with or recede from both ends of the absorbent main body in the width direction. 
         [0014]    According to claim  2 , in the absorbent article according to claim  1 , the absorbent main body includes a pair of wings projecting in width directions from the absorbent main body in a state of being unpacked from a packed state, and in the packed state, the pair of wings are folded back on the cover sheet. 
         [0015]    According to claim  3 , in the absorbent article according to claim  1 , the cover sheet covers entirely the contact surface of the topsheet at which the top sheet and the excretion portion of the wearer are to be in contact with each other. 
         [0016]    According to claim  4 , in the absorbent article according to claim  1 , an edge of the cover sheet in the longitudinal direction coincides with an edge of the absorbent main body in the longitudinal direction, and an edge of the cover sheet in the width direction coincides with an edge of the absorbent main body in the width direction. 
         [0017]    According to claim  5 , in the absorbent article according to claim  1 , the cover sheet is bonded to the topsheet at a bonding position at which the topsheet and the backsheet are bonded to each other, among peripheral edge positions of the absorbent main body. 
         [0018]    According to claim  6  in the absorbent article according to claim  1 , the cover sheet contains a heat-weldable fiber. 
         [0019]    According to claim  7 , in the absorbent article according to any one of claims  1  to  6 , the cover sheet has at least one of liquid-permeability and hydrophilicity. 
         [0020]    According to claim  7 , in the absorbent article according to any one of claims  1  to  6 , the cover sheet has water-disintegrability. 
         [0021]    According to the present invention, an absorbent main body can be easily positioned at an appropriate position of undergarment, and a topsheet can be kept clean during the mounting process. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    [ FIG. 1 ]  FIG. 1  shows a first embodiment of the present invention and is an overall perspective view of a sanitary napkin. 
           [0023]    [ FIG. 2 ]  FIG. 2  shows the first embodiment of the present invention and is a plan view of the sanitary napkin. 
           [0024]    [ FIG. 3 ]  FIG. 3  shows the first embodiment of the present invention, and is a cross-sectional view taken along the line A-A of  FIG. 2 . 
           [0025]    [ FIG. 4 ]  FIG. 4  shows the first embodiment of the present invention, and is a perspective view showing a mounting process of the sanitary napkin. 
           [0026]    [ FIG. 5 ]  FIG. 5  shows the first embodiment of the present invention, and is a perspective view showing the mounting process of the sanitary napkin. 
           [0027]    [ FIG. 6 ]  FIG. 6  shows a second embodiment of the present invention, and is a plan view of a sanitary napkin. 
           [0028]    [ FIG. 7 ]  FIG. 7  shows the second embodiment of the present invention, and is a cross-sectional view taken along the line B-B of  FIG. 6 . 
           [0029]    [ FIG. 8 ]  FIG. 8  shows a third embodiment of the present invention, and is a plan view of a sanitary napkin. 
           [0030]    [ FIG. 9 ]  FIG. 9  shows the third embodiment of the present invention, and is a cross-sectional view taken along the line C-C of  FIG. 8 . 
           [0031]    [ FIG. 10 ]  FIG. 10  shows a fourth embodiment of the present invention, and is a plan view of a sanitary napkin. 
           [0032]    [ FIG. 11 ]  FIG. 11  shows the fourth embodiment of the present invention, and is a cross-sectional view taken along the line D-D of  FIG. 10 . 
           [0033]    [ FIG. 12 ]  FIG. 12  shows a fifth embodiment of the present invention, and is a plan view of a sanitary napkin. 
           [0034]    [ FIG. 13 ]  FIG. 13  shows the fifth embodiment of the present invention, and is a cross-sectional view taken along the line E-E of  FIG. 12 . 
           [0035]    [ FIG. 14 ]  FIG. 14(   a ) is a perspective view of a sanitary napkin of a first conventional example, and  FIG. 14(   b ) is a cross-sectional view taken along the line F-F of  FIG. 14(   a ). 
           [0036]    [ FIG. 15 ]  FIG. 15(   a ) is a perspective view of a sanitary napkin of a second conventional example, and  FIG. 15(   b ) is a cross-sectional view taken along the line G-G of  FIG. 15(   a ). 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0037]    Hereinafter, embodiments of the present invention will be described on the basis of the drawings. 
         [0038]      FIGS. 1 to 5  show a first embodiment of the present invention.  FIG. 1  is an overall perspective view of a sanitary napkin.  FIG. 2  is a plan view of the sanitary napkin.  FIG. 3  is a cross-sectional view taken along the line A-A of  FIG. 2 . Each of  FIGS. 4 and 5  is a perspective view showing a mounting process of the sanitary napkin. 
         [0039]    As shown in  FIGS. 1 to 3 , a sanitary napkin  1 A, which is an absorbent article, includes a napkin main body  2 , which is an absorbent main body, and a cover sheet  20 A provided to the napkin main body  2 . 
         [0040]    The napkin main body  2  includes a topsheet  3 , a backsheet  4 , an absorber  5 , a pair of side-sheets  6 , and a pair of wings  7 . The topsheet  3  is liquid-permeable and is configured to come into contact with the skin of a wearer. The backsheet  4  is liquid-impermeable and is configured to come into contact with undergarment, which are clothing. The absorber  5  is disposed between the topsheet  3  and the backsheet  4  and is configured to absorb liquid. The pair of side-sheets  6  are liquid-impermeable and are disposed outside outer peripheries of the topsheet  3  along the longitudinal direction. The pair of wings  7  project in width directions from outer peripheries of the pair of side-sheets  6  and of the backsheet  4  along the longitudinal direction. 
         [0041]    The dimension of the topsheet  3  in the longitudinal direction is equal to the dimension of the backsheet  4  in the longitudinal direction. The dimension of the topsheet  3  in the width direction is smaller than the dimension of the backsheet  4  in the width direction. The dimension of the backsheet  4  in the width direction is equal to the dimension which is the total of the dimensions of the pair of side-sheets  6  in the width direction and the dimension of the topsheet  3  in the width direction. The topsheet  3  and the pair of side-sheets  6  are bonded together at mutually overlapped portions by using an adhesive paste such as a hot melt adhesive. The pair of side-sheets  6  and the backsheet  4  are bonded together by using an adhesive paste such as a hot melt adhesive over substantially the entire region of outer peripheries including outer peripheries along the longitudinal direction as well as portions projecting in the width direction. The topsheet  3  and the absorber  5  are bonded to each other at an appropriate position by using an adhesive paste such as a hot melt adhesive. Adhesive portions  8  are provided to the backsheet  4  on a contact surface thereof which is configured to come into contact with clothing. The adhesive portions  8  are configured to prevent misalignment between the napkin main body  2  and the clothing. A release sheet  9  is bonded to outer surfaces of the adhesive portions  8 . 
         [0042]    The absorber  5  includes a laminated body of crushed pulp and tissue with which the laminated body is wrapped. The absorber  5  may be an absorber obtained by blending a high-absorbent polymer powder or a thermoplastic synthetic fiber with the above-described crushed pulp. 
         [0043]    The pair of wings  7  in a state of being unpacked from an individually packed state (shown in  FIG. 1  by the solid line) project in the width direction from the napkin main body portion  2 . As the pair of wings  7 , portions of the pair of side-sheets  6  and portions of the backsheet  4  project in the width direction from the napkin main body portion  2 . Note that the pair of wings  7  may be formed of members independent from the pair of side-sheets  6  and the backsheet  4 . It is not necessary for the backsheet  4  to extend to end portions of the wings  7 . Adhesive portions  10  are provided to surfaces of the pair of wings  7  on the side of the backsheet  4 , respectively. The adhesive portions  10  are configured to prevent the misalignment between the napkin main body  2  and clothing. The pair of wings  7  in a before-use (individually packed) state (shown in  FIG. 1  by the chain double-dashed lines) are folded back on the side of the topsheet  3 . Release sheets (not shown) are bonded to outer surfaces of the adhesive potions  10 . 
         [0044]    The cover sheet  20 A is formed of a material containing a heat-weldable fiber. The cover sheet  20 A is disposed directly on a contact surface on which the skin of a wearer comes into contact with the topsheet  3 . The pair of wings  7  are disposed on the cover sheet  20 A while being in a state of being folded back on the side of the topsheet  3 . The cover sheet  20 A covers at least a contact surface on which the excretion portion of a wearer comes into contact with the topsheet  3 . Both ends of the cover sheet  20 A in the longitudinal direction and in the width direction at least partially coincide with or recede from those of the napkin main body  2  in the longitudinal direction and in the width direction. Accordingly, the contour of the napkin main body  2  can be seen by visual observation even when the topsheet  3  is covered with the cover sheet  20 A. In this first embodiment, the dimensions of the cover sheet  20 A in the longitudinal direction and in the width direction are substantially equal to the dimensions of the topsheet  3  in the longitudinal direction and in the width direction, respectively. The positions of front and rear edges of the cover sheet  20 A in the longitudinal direction are the same as the positions of front and rear edges of the napkin main body  2  in the longitudinal direction. The cover sheet  20 A covers entirely the contact surface of the topsheet  3  at which the topsheet  3  and the skin of a wearer are to be in contact with each other. 
         [0045]    The cover sheet  20 A is temporarily attached to the topsheet  3  at the same positions as the bonding positions at which the topsheet  3  and the backsheet  4  are bonded to each other by using an adhesive paste such as a hot melt adhesive. Specifically, the cover sheet  20 A is temporarily attached to the topsheet  3  at a front end position and a rear end position among peripheral edge positions of the napkin main body  2  by means of heat-welding portions  11 . 
         [0046]    Conventionally, in a manufacturing process of an absorbent article, the absorber  5  is shaped, and then the topsheet  3  and the backsheet  4  are bonded to each other by using an adhesive paste such as a hot melt adhesive with the absorber  5  interposed therebetween. After the topsheet  3  and the backsheet  4  are bonded to each other, the topsheet  3  and the backsheet  4  are welded to each other by heating outer peripheries of the absorber  5  over certain widths, for the purpose of further increasing the bonding strength of the bonded portions. This results in the fixation (sealing) of the absorber  5  at a predetermined position. After the sealing, the absorber  5  is cut into a shape of a product. Meanwhile, in a manufacturing process of this embodiment additionally includes a step of folding the cover sheet  20 A to be on the contact surface of the topsheet  3 , the skin of a wearer coming into contact with the contact surface, thereby fixing the absorber at a predetermined position. The step of folding is included before the sealing step of welding an outer peripheral portion of the absorber  5 . A sealing step is performed with the cover sheet  20 A, the topsheet  3 , and the backsheet  4  stacked together. When the cover sheet  20 A or the topsheet  3  contains a heat-weldable fiber, pieces of the heat-weldable fiber are thermally welded to each other by heat. As a result, the cover sheet  20 A and the topsheet  3  are temporarily attached to each other, without providing a paste or an adhesive between the cover sheet  20 A and the topsheet  3 . Accordingly, the cover sheet  20 A can be temporarily attached without adding a separate temporarily attaching step of the cover sheet  20 A, thereby preventing the manufacturing process from being complicated. 
         [0047]    The cover sheet  20 A is formed of a flexible and hydrophilic sheet member. Specifically, non-woven fabrics (such as an air-through non-woven fabric, a spunbond non-woven fabric, a point bond non-woven fabric, and a spunlace non-woven fabric) and airlaid pulp sheets are preferable. Among those a spunlace non-woven fabric is particularly preferable. The spunlace non-woven fabric is a non-woven fabric manufactured by the spunlace method from a substantially uniform blend of 60% of a rayon fiber of 1.7 dtex with a fiber length of 40 mm and 40% of a polyester fiber of 2.2 dtex with a fiber length of 51 mm. The cover sheet  20 A has a weight per square meter (hereinafter referred to as a basis weight) of 50 g/m2, and a thickness of 0.55 mm. 
         [0048]    In the sanitary napkin  1 A configured as above, the napkin main body  2  in the before-use state is folded along with the cover sheet  20 A, and housed in an individual package, in general. 
         [0049]    Next, brief description is given of a mounting procedure of the sanitary napkin  1 A. First, undergarment  30  are displaced to a position around the knees. If being in an individually packed state, the individual package is peeled off, and the sanitary napkin  1 A is taken out. Then the sanitary napkin  1 A is unfolded. When the individual package is peeled off, the release sheets  9  (not shown) provided to the backsheet  4  and the pair of wings  7  of the sanitary napkin  1 A are peeled off. Next, the pair of wings  7  are held by the hand, and the napkin main body  2  is positioned at an appropriate position of the undergarment  30 . As shown in  FIG. 4 , the positioned napkin main body  2  is pressed to the undergarment  30  with the fingers or the palms to thereby paste the napkin main body  2  to the undergarment  30  by means of the adhesive portions  8 . Next, as shown in  FIG. 5 , the wings  7  are folded back at lateral edges of a crotch portion  30   a  of the undergarment  30 . The folded-back wings  7  are pressed to the undergarment  30  with the fingers or the palms, thereby pasting the wings  7  to the undergarment  30  by means of the adhesive portions  10 . Thereafter, the cover sheet  20 A is peeled off from the napkin main body  2 . This completes the mounting. Note that, the adhesive portions  8  provided to the backsheet  4  may be pasted to the undergarment  30  after the adhesive portions  10  of the wings  7  are pasted to the undergarment  30 . 
         [0050]    As has been described above, in the sanitary napkin  1 A, the cover sheet  20 A, which is detachable, is provided on the surface of the topsheet  3  of the napkin main body  2 . The cover sheet  20 A covers at least the contact surface on which the excretion portion of the wearer comes into contact with the topsheet  3 . The length of the cover sheet  20 A in the longitudinal direction is equal to the length of the napkin main body  2  in the longitudinal direction. The cover sheet  20 A is disposed directly on the contact surface on which the skin of the wearer comes into contact with the topsheet  3 . Accordingly, the user can visually observe the contour of the napkin main body  2  when mounting the napkin main body  2  on the undergarment  30 . This enables the napkin main body  2  to be easily mounted on the undergarment  30  at an appropriate position. Moreover, since the napkin main body  2  with the cover sheet  20 A attached thereto can be mounted on the undergarment  30 , the user can perform the mounting without direct contact with the topsheet  3 . Then, the cover sheet  20 A can be detached from the napkin main body  2  after the napkin main body  2  is mounted on the undergarment  30 . Accordingly, the topsheet  3  is kept clean during the mounting process. 
         [0051]    The cover sheet  20 A is hydrophilic. Accordingly, the cover sheet  20 A detached from the napkin main body  2  can be used for wiping, and hence is convenient. Especially, the cover sheet  20 A of this embodiment is formed of a spunlace non-woven fabric. The basis weight of the cover sheet  20 A is 50 g/m2, and the thickness thereof is 0.55 mm. Since this non-woven fabric is relatively thick, sufficient wiping can be achieved even when the skin is wet. 
         [0052]    The cover sheet  20 A has an outer diameter size enough to cover entirely the contact surface of the topsheet  3  at which the topsheet  3  and the skin of the wearer are to be in contact with each other. Accordingly, the fingers of the user can be surely prevented from coming into contact with the topsheet  3 . 
         [0053]    The cover sheet  20 A contains a heat-weldable fiber. Moreover, as described above, the cover sheet  20 A is stacked on the contact surface on which the skin of the wearer comes into contact with the topsheet  3 , and then the sealing step is performed. In the sealing step, the absorber  5  is fixed between the topsheet  3  and the backsheet  4 , and then cut into a shape of a product. Accordingly, the cover sheet  20 A is temporarily attached to the topsheet  3  at the same positions as the positions at which the topsheet  3  and the backsheet  4  are bonded to each other, among peripheral edge positions of the napkin main body  2 . Here, since no adhesive paste or the like is provided between the cover sheet  20 A and the napkin main body  2 , the wearer can easily peel off the cover sheet  20 A when mounting the napkin. Accordingly, this attachment is referred to as “temporary attachment.” 
         [0054]    As deceived above, without providing a separate temporarily attaching step for the temporary attachment of the cover sheet  20 A, the cover sheet  20 A can be temporarily attached to the topsheet  3  by means of the heat-welding portions  11 . Accordingly, the manufacturing process can be prevented from being complicated. Moreover, in the topsheet  3 , no temporary-attachment portions exists in a central region encompassing at least the contact surface with which the excretion portion of the wearer comes into contact. Accordingly, no damage due to the temporary attachment is inflicted on the topsheet  3 , and a favorable texture can surely be obtained in at least the central region of the topsheet  3 . Furthermore, partial exposure of the topsheet  3  does not occur, which would otherwise occur when the cover sheet  20 A is partially curled up. Accordingly, the topsheet  3  can surely be protected. Moreover, the wearer can easily detach the cover sheet  20 A from the napkin main body  2  by pinching a center portion of the cover sheet  20 A. Furthermore, since the cover sheet  20 A is temporarily attached to the napkin main body  2  by means of the heat-welding portions  11 , no paste or adhesive remains at positions at which the cover sheet  20 A is bonded, after the cover sheet  20 A is detached. Accordingly, not only the topsheet  3  can be kept clean, but also the deterioration in texture can be prevented in the central region encompassing the contact surface with which the excretion portion of the wearer come into contact. 
         [0055]    The sanitary napkin  1 A has the pair of wings  7 . When the pair of wings  7  are folded back on the side of the topsheet  3 , the pair of wings  7  are disposed on a top surface of the cover sheet  20 A. The wearer can mount the wings  7  on the lateral edges of the crotch portion  30   a  of the undergarment  30  with the cover sheet  20 A being attached to the napkin main body  2 . Accordingly, in the mounting process, the topsheet  3  can be kept clean. The present invention can of course be applied to sanitary napkins having no wings. 
         [0056]    Note that, as in the case of this embodiment, when the sanitary napkin  1 A having the wings  7  is produced, the topsheet  3  and the side-sheets  6  constituting the wings  7  are integrated, and then the topsheet  3 , the wings  7 , and the backsheet  4  are joined together by using a paste or a adhesive. Next, the cover sheet  20 A is stacked on the contact surface on which the skin of the wearer comes into contact with the napkin main body  2  and then the topsheet  3  and the backsheet  4  are sealed. Preferably, after the sealing, cutting into a shape of a product is performed, and then the wings  7  are folded back to be on the top surface of the cover sheet  20 A stacked on the contact surface on which the skin of the wearer comes into contact with the napkin main body  2 . 
         [0057]      FIGS. 6 and 7  show a second embodiment of the present invention.  FIG. 6  is a plan view of a sanitary napkin, and  FIG. 7  is a cross-sectional view taken along the line B-B of  FIG. 6 . 
         [0058]    When a sanitary napkin  1 B according to this second embodiment is compared with the sanitary napkin  1 A according to the above-described first embodiment, the sanitary napkin  1 B has a cover sheet  20 B which has a different structure and a different temporarily attaching mechanism thereof. 
         [0059]    Specifically, as shown in  FIGS. 6 and 7 , the cover sheet  20 B has a contour size which is substantially equal to that of the napkin main body  2  excluding the pair of wings  7 . In addition, the cover sheet  20 B is temporarily attached at the front and rear positions and at four corner positions on both sides among the peripheral edge positions of the napkin main body  2 , by means of the heat-welding portions  11 , and heat-welding portions  11   a.    
         [0060]    Other components are the same as those in the first embodiment, and hence description thereof is omitted. In the drawings, same reference signs denote same components for clarification. 
         [0061]    According to the second embodiment, the entire region of the contact surface (the topsheet  3  and the side-sheets  6 ) on which the skin of the wearer comes into contact with the napkin main body  2  can be kept clean. 
         [0062]      FIGS. 8 and 9  show a third embodiment of the present invention.  FIG. 8  is a plan view of a sanitary napkin, and  FIG. 9  is a cross-sectional view taken along the line C-C of  FIG. 8 . 
         [0063]    When a sanitary napkin  1 C according to this third embodiment is compared with the sanitary napkin  1 A according to the above-described first embodiment, the sanitary napkin IC has a cover sheet  20 C which has a different structure and a different temporarily attaching mechanism thereof. 
         [0064]    Specifically, as shown in  FIGS. 8 and 9 , the cover sheet  20 C has a contour size which is substantially equal to that of the napkin main body  2  excluding the pair of wings  7 . In addition, the cover sheet  20 C is temporarily attached at the front and rear positions, at four corner positions on both sides, and at peripheral edge positions of the wings  7  among the peripheral edge positions of the napkin main body  2 , by means of the heat-welding portions  11 , the heat-welding portions  11   a,  and heat-welding portions  11   b.    
         [0065]    Other components are the same as those in the first embodiment, and hence description thereof is omitted. In the drawings, same reference signs denote same components for clarification. 
         [0066]    According to the third embodiment, the entire region of the contact surface (the topsheet  3  and the side-sheets  6 ) on which the skin of the wearer comes into contact with the napkin main body  2  can be kept clean. Moreover, the productivity is excellent because, in the sealing step during the manufacturing, the cover sheet  20 C is temporarily attached to the napkin main body  2  by means of the heat-welding portions  11 ,  11   a,  and  11   b,  and then the temporarily attached cover sheet  20 C is cut into the same size as that of the napkin main body  2 . Moreover, the wings  7  can be kept clean. 
         [0067]      FIGS. 10 and 11  show a fourth embodiment of the present invention.  FIG. 10  is a plan view of a sanitary napkin, and  FIG. 11  is a cross-sectional view taken along the line D-D of  FIG. 10 . 
         [0068]    When a sanitary napkin  1 D according to this fourth embodiment is compared with the sanitary napkin  1 A according to the above-described first embodiment, the sanitary napkin  1 D is different only in the temporarily attaching mechanism of a cover sheet  20 D. 
         [0069]    Specifically, as shown in  FIGS. 10 and 11 , the cover sheet  20 D has the same contour size as that of the topsheet  3 , as in the case of the first embodiment. The entire peripheral edge of the cover sheet  20 D is temporarily attached to the topsheet  3  by means of the heat-welding portions  11 , as well as and heat-welding portions  11   c.    
         [0070]    Other components are the same as those in the first embodiment, and hence description thereof is omitted. In the drawings, same reference signs denote same components for clarification. 
         [0071]    According to the fourth embodiment, unless the cover sheet  20 D is peeled off, the cleanness of the topsheet  3  can be secured almost completely. 
         [0072]      FIGS. 12 and 13  show a fifth embodiment of the present invention.  FIG. 12  is a plan view of a sanitary napkin, and  FIG. 13  is a cross-sectional view taken along the line E-E of  FIG. 12 . 
         [0073]    When a sanitary napkin  1 E according to this fifth embodiment is compared with the sanitary napkin  1 B according to the above-described second embodiment, the sanitary napkin  1 E is different only in the temporarily attaching mechanism/structure of a cover sheet  20 E. 
         [0074]    Specifically, as shown in  FIGS. 12 and 13 , the cover sheet  20 E has substantially the same contour size as that of the napkin main body  2  excluding the pair of wings  7 . In addition, the cover sheet  20 E is temporarily attached at the front and rear positions and at all lateral positions on the both sides among peripheral edge positions of the napkin main body  2  by means of the heat-welding portions  11 ,  11   c . The heat-welding portion  11  at the front position is divided into pieces at two positions, and the napkin main body  2  is not temporarily attached at a front center position. 
         [0075]    Other components are the same as those in the first embodiment, and hence description thereof is omitted. In the drawings, same reference signs denote same components for clarification. 
         [0076]    According to the fifth embodiment, the entire contact surface of the topsheet  3  and the side-sheets  6  can be kept clean, the skin of the wearer coming into contact with the napkin main body  2  on the contact surface. Moreover, since the temporarily attaching portion is divided at the front position of the cover sheet  20 E, the fifth embodiment has an advantage that the cover sheet  20 E can easily peeled off. Specifically, the cover sheet  20 E can also be peeled off by pinching the center of the cover sheet  20 E at the front position with the fingers. Note that, the heat-welding portion  11  of the cover sheet  20 E at the rear position may be divided, or both the heat-welding portions  11  at the front position and at the rear position may be divided. 
         [0077]    The above-described embodiments have shown the cases where the cover sheets  20 A to  20 E have various contour dimensions. However, each of the cover sheets only needs to cover at least the contact surface on which the excretion portion of the wearer comes into contact with the topsheet  3 . It is only necessary that the both ends of the cover sheet in the longitudinal direction and in the width direction at least partially coincide with or recede from the both ends of the napkin main body  2 , respectively. With such contour dimensions, the wearer can see the contour of the napkin main body  2  through a visual observation from above the cover sheet. Accordingly, the wearer can easily position the napkin main body  2  at an appropriate position of undergarment. Moreover, since the topsheet  3  is covered with the cover sheet, the topsheet  3  can be kept clean in the mounting process. 
         [0078]    When the cover sheets  20 A to  20 E are used for wiping, the basis weight of each of the cover sheets  20 A to  20 E is preferably 20 to 120 g/m 2 , and further more preferably 30 to 80 g/m 2 . If the basis weight is less than 20 g/m 2 , substances wiped by the cover sheets  20 A to  20 E may seep out of the cover sheets  20 A to  20 E, and soil the hand of the wearer at the wiping of the body. If the basis weight exceeds 120 g/m 2 , the cover sheet is too hard for use in wiping the body. Moreover, besides the basis weight, the bending resistance determined by the cantilever method is preferably 100 mm or less, and further preferably 80 mm or less. If the bending resistance exceeds 100 mm, the drape property becomes poor, and the wiping performance is also lowered. 
         [0079]    Note that, when each of the cover sheets  20 A to  20 E is not intended to be used for wiping but intended to be used only for covering the topsheet  3 , each of the cover sheets  20 A to  20 E may be a film, and in such a case a basis weight of 10 g/m 2  or more is sufficient. 
         [0080]    Each of the cover sheets  20 A to  20 E may be formed of a liquid-permeable material. Each of the liquid-permeable cover sheets  20 A to  20 E are formed, for example, by subjecting a hydrophobic fiber to a hydrophilic treatment. With the use of a liquid-permeable sheet member, menstrual blood and the like can permeate into the underlining layers even when the wearer conducts the mounting without peeling the cover sheet  20 A by mistake. 
         [0081]    Each of the cover sheets  20 A to  20 E may be formed of a water-disintegrable material. Specifically, the water-disintegrable material is one obtained by substantially uniformly blending 70% of pulp, 25% of rayon of 1.1 dtex with a fiber length of 7 mm, and 5% of Tencel of 1.7 dtex with a fiber length of 3 mm with each other, and then forming a sheet therefrom. The basis weight is 45 g/m 2 , and the thickness is 0.5 mm. The use of the water-disintegrable material allows the cover sheets  20 A to  20 E to be flushed down a toilet, and hence provides convenience. 
         [0082]    Each of the cover sheets  20 A to  20 E may be formed of an antibacterial material. A specific example is a spunlace non-woven fabric containing a catechin component. It is possible to inhibit proliferation of unwanted bacteria at the excretion portion of the wearer. 
         [0083]    Each of the cover sheets  20 A to  20 E may be formed of a sheet member having a deodorizing capability. This can prevent the formation of odor. More preferably, each of the cover sheets  20 A to  20 E is provided with two or more functionalities by combining the above-described various materials. For example, as the cover sheets  20 A to  20 E, those which have both liquid-permeability and hydrophilicity are used. The use of such sheets improves the wiping performance of the cover sheets  20 A to  20 E in the use of wiping. Alternatively, as the cover sheets  20 A to  20 E, those which have both liquid-permeability and water-disintegrability are used. The use of such sheets enables the cover sheets  20 A to  20 E to be flushed down a toilet after the use for wiping, providing an extremely high convenience. 
         [0084]    A moisture retentive material may be applied to the cover sheets  20 A to  20 E. Moreover, the cover sheets  20 A to  20 E may be passed through a liquid agent in which a functional material is dissolved. Alternatively, a portable spray can filled with a liquid agent in which a functional material is dissolved is included in a package of a product of the sanitary napkin  1 A, or is sold separately therefrom. The wearer can provide the cover sheets  20 A to  20 E with desired functionalities by spraying the liquid agent in which the functional material is dissolved onto the cover sheets  20 A to  20 E, as needed. 
         [0085]    The 5% elongation strength of each of the cover sheets  20 A to  20 E in a conveyance direction at the time of manufacturing is preferably 0.2 N/25 mm or higher because of the following reason. Specifically, if the 5% elongation strength is less than 0.2 N/25 mm, the cover sheets  20 A to  20 E are elongated in the conveyance direction in the manufacturing at the time of the manufacturing and conveying. If the cover sheets  20 A to  20 E are temporarily attached while being stretched, a stress to restore the original state acts on the cover sheets  20 A to  20 E, and hence the temporarily attached cover sheets  20 A to  20 E may be peeled off before use. 
         [0086]    Each of the cover sheets  20 A to  20 E may be temporarily attached to the napkin main body  2  while being folded one or more times. When each of the cover sheets  20 A to  20 E peeled off from the napkin main body  2  is unfolded, the usable area is enlarged. Accordingly, such cover sheets  20 A to  20 E are convenient. 
         [0087]    The above-described embodiments have shown the cases where the present invention is applied to the sanitary napkins  1 A to  1 E, which are absorbent articles. However, the present invention is applicable to so-called liners, incontinence aids (also referred to as incontinence pads) and the like. Examples of the liners, and incontinence pads to which the present invention is applicable include those of a type in which a topsheet and a backsheet are provided but no absorber is provided between the topsheet and the backsheet, those of a type in which a topsheet, an absorber, and a backsheet are provided, and the like. 
         [0088]    In many cases, the conveyance direction in the manufacturing of the sanitary napkins  1 A to  1 E is a longitudinal direction of the products. However, unlike the conveyance direction in the manufacturing of the sanitary napkins  1 A to  1 E, the conveyance direction in the manufacturing of liners is the width direction of the products in many cases. Accordingly, in the cases of liners, an edge of each cover sheet in the longitudinal direction can be easily trued up with an edge of each napkin main body, which is an absorbent main body, in the longitudinal direction. Specifically, the cutting into the cover sheets and the cutting into the absorbent main bodies can be performed in a single cutting step. 
         [0089]    Each of the sanitary napkins  1 A to  1 E is preferably provided with a notice prohibiting the use thereof with each of the cover sheets  20 A to  20 E attached to the napkin main body  2 . However, if the cover sheets  20 A to  20 E are made of a liquid-permeable material, the body fluid can permeate to the side of the napkin main body  2  though the cover sheets  20 A to  20 E, and the original functionalities of the sanitary napkins  1 A to  1 E can be retained, even when the napkin main body  2  is mounted with the cover sheets  20 A to  20 E remaining thereon. 
         [0090]    Note that the entire contents of Japanese Patent Application No. 2008-016469 (filed on Jan. 28, 2008) are incorporated herein by reference. 
         [0091]    As has been described above, the absorbent article according to the present invention enables the absorbent main body to be easily positioned at an appropriate position of undergarment, and enables the topsheet to be kept clean during the mounting process. Accordingly, the absorbent article is useful for liners, incontinence aids, diapers, and sanitary napkins.