Abstract:
The wearing article is provided with a fastening system adapted to releasably connecting front and rear waist regions defining a waist-opening. The fastening system consisting of engaging fasteners located on transversely opposite side edges of the rear waist region and landing fasteners located on transversely opposite side zones of the front waist region. Each of the engaging fasteners has an insert and an engaging portion while each of the landing fasteners has a pocket adapted to receive the insert and a landing portion which is formed on the outer surface of the pocket and with which the engaging portion is releasably engaged.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     The present invention relates to wearing articles for direct and indirect containment of body wastes and having so-called waist fasteners. More particularly, the present invention relates to such wearing articles provided with a fixed point type fastening system used to fasten a waist region of the wearing article, particularly, such as disposable diapers, diaper covers, training pants, incontinence pants or the like and thereby to retain the article about an appropriate region of a wearer&#39;s body.  
         [0002]     A fixed point type fastening system is well known (See WO 02/051278 A2, hereinafter referred to as “Citation 1”). The fastening system disclosed in Citation 1 comprises a first component having a hollow portion and a second component adapted to be inserted into this hollow portion. The hollow portion at least partially defines a surface adapted to be releasably engaged with at least one surface defined by the second component. These two surfaces adapted to be releasably engaged with each other respectively comprise a plurality of hooks and a plurality of loops. It is claimed by Citation 1 that such a fastener is advantageous for use with the absorbent article.  
         [0003]     The absorbent article provided with an improved fastening system is also well known (See WO 02/11657 A2, hereinafter referred to as “Citation 2”). The fastening system disclosed in Citation 2 comprises face-to-face paired flap-like backings extending outward from each side edge in one of waist regions, on one hand, and a flap-like backing extending outward from each side edge in the other waist region and adapted to be interposed between the face-to-face paired flap-like backings, on the other hand. The face-to-face paired flap-like backings in the one waist region are provided on the inner surface thereof with a plurality of hooks and/or loops while the flap-like backing in the other waist region is provided on both the surfaces thereof with a plurality of loops and/or hooks adapted to be releasably engaged with the hooks and/or loops of the face-to-face paired flap-like backings.  
         [0004]     In the case of the fastening system disclosed in Citation 1, basically characterized in that the second component is inserted into the hollow portion of the first component, both the hollow portion of the first component and the second component are provided with the hooks or the loops. These hooks and loops may be at least partially engaged one with another during insertion in the vicinity of entrance of the hollow portion and prevent the second component from being sufficiently inserted into the hollow portion. To solve such a problem, the user must insert the second component into the hollow portion with one hand while the hollow portion is sufficiently opened with the other hand. This fastening system is thus accompanied with inconvenience that the user must handle the fastening system with both hands in preparation for the wearing article.  
         [0005]     The fastening system disclosed in Citation 2 also is accompanied with the inconvenience that the user fastening system must handle the fastening system with both hands in preparation for wearing the article. Specifically, the user must open the face-to-face paired flap on each side of the one waist region with both hands or one hand and then interpose the flap on each side of the other waist region between the face-to-face paired flaps with the other hand. In addition, this fastening system is disadvantageously distinguished from the fixed point type fastening system in that a position at which the hooks are engaged with the loops must be appropriately selected by the user him- or herself. So far as this aspect is concerned, the fastening system disclosed in Citation 2 is similar to the other fastening systems of prior art requiring such positioning.  
         [0006]     It is assumed that the second component has not been properly inserted into the hollow portion of the first component as the fastening system disclosed in Citation 1 has often been the case or the positioning has not been properly selected as the fastening system disclosed in Citation 2 has often been the case. In both cases, it will be impossible to fasten the wearing article on the appropriate region of the wearer&#39;s body and consequentially the wearing article will readily slip down. Due to this, body wastes will leak beyond the leg-openings of the article.  
       SUMMARY OF THE INVENTION  
       [0007]     It is an object of the present invention to provide a wearing article provided with a fixed point type fastening system allowing the user to carry out handling of the fastening system with one hand to fasten the article&#39;s front and rear waist regions together in such a manner that a possibility of body wastes leakage due to slip down of the article can be substantially eliminated.  
         [0008]     According to the present invention, there is provided a wearing article comprising first and second waist regions each having body-facing surface and garment-facing surface, the first and second waist regions cooperating together to define a waist-opening, a crotch region extending between and cooperating with the first and second waist regions to define a pair of leg-openings, and a fastening system releasably connecting the first and second waist regions.  
         [0009]     The fastening system according to the present invention comprises engaging fasteners respectively located on transversely opposite side edges of the first waist region and landing fasteners located on the garment-opposing surface of transversely opposite side zones of the second waist region. Each of the engaging fasteners has an insert and an engaging portion while each of the landing fasteners has a pocket adapted to receive the insert and a landing portion formed on an outer surface of the pocket so that the engaging portion releasably engages the landing portion.  
         [0010]     At least one of the first and second waist regions is provided with a elastic means serving to elastically adjust a circumferential waist dimension defined by the first and second waist regions.  
         [0011]     The present invention may include preferred embodiments as follow:  
         [0012]     The engaging fasteners and the landing fasteners may be located along an elastically stretch- and contractable line created by the elastic means on the first and second waist regions.  
         [0013]     The engaging portions and the inserts may include a rigid panel formed integrally therewith and the inserts slant at a given angle with respect to the engaging portions, respectively.  
         [0014]     Each of the engaging portions may be formed by securing a hook member having a plurality of hook elements projecting from a sheet-like backing to a zone of the rigid panel defining the backing for the engaging portion.  
         [0015]     Each of the engaging portions may be formed by coating a zone of the rigid panel defining the backing for the engaging portion with a pressure-sensitive adhesive.  
         [0016]     Each of the pockets may be formed by a sleeve having an opening oriented outward with respect to a side edge of the second waist region to which this pocket is contiguous.  
         [0017]     Each of the landing portions may be formed from a fibrous texture defining the sleeve and functioning as the loop elements.  
         [0018]     Each of the landing portions may be formed by securing a loop member having a plurality of loop elements projecting from a sheet-like backing to the sleeve.  
         [0019]     Each of the inserts may have a stiffness value in a range of 0.05N/cm to 2N/cm as measured by the Taber&#39;s method.  
         [0020]     The elastic means may comprise a pair of elastically stretch- and contractable ear flaps extending outward from the side edges of the first waist region.  
         [0021]     The first and second waist regions and the crotch region may be formed by an absorbent chassis.  
         [0022]     The chassis may comprise a liquid-pervious inner sheet, a liquid-impervious outer sheet and a liquid-absorbent core interposed between these inner and outer sheets.  
         [0023]     The wearing article according to the present invention may include a waist fastening mechanism in the form of a fixed point type fastening system composed of the engaging fasteners and the landing fasteners. For such a fixed point type fastening system, it is unnecessary to adjust the position at which the desired engagement should be established since the position of engagement is predetermined. Additionally, the wearer or his or her helper (e.g., mother, care-giver, etc.) may introduce the inserts of the respective engaging fasteners into the pockets of the respective landing fasteners through the respective openings with one hand and then press the engaging portions of the respective engaging fasteners against the landing portions of the respective landing fasteners to achieve the desired engagement between the engaging fasteners and the landing fasteners. For example, when the user wears the article while standing, it is unnecessary for the user to align relative positions of the engaging fasteners and the landing fasteners with both hands and to carefully bring these relative positions into engagement using both hands as it is necessary for the wearer lying down.  
         [0024]     Once the engaging fasteners have been engaged with the landing fasteners in this manner, a circumferential waist dimension defined by the first and second waist regions is automatically adjusted under the elastic effect of the elastic means provided in at least one of the first and second waist regions. Such an automatic adjustment combined with the simplified operation for the engagement facilitates the wearer him- or her helper or the caregiver to put the article on the wearer&#39;s body.  
         [0025]     The fixed point type fastening system ensures that the engaging fasteners engage the landing fasteners at appropriate positions and thereby the article is appropriately stabilized about the wearer&#39;s body. Thus, it is unlikely that an undesirable clearance might be created between the leg-openings of the article and the wearer&#39;s legs due to slip down of the article and consequentially body wastes might leak through such a clearance.  
         [0026]     The embodiment of the invention wherein the engaging fasteners and the landing fasteners may be located along an elastically stretch- and contractable line created by the elastic means on the first and second waist regions allows a circumferential waist dimension defined by the first and second waist regions to be automatically and appropriately adjusted and allows the elastic means for this purpose to be effectively utilized.  
         [0027]     According to the embodiment wherein the engaging portions and the inserts include a rigid panel formed integrally therewith and the inserts slant at a given angle with respect to the engaging portions, respectively as well as according to the embodiment wherein each of the pockets is formed by a sleeve having an opening oriented outward with respect to a side edge of the second waist region to which this pocket is contiguous, the engaging portions can be utilized as finger-grip tabs to introduce the inserts into the respective pockets quickly and reliably when the engaging fasteners are engaged with the landing fasteners. In addition, there is no anxiety that the article might slip down along the wearer&#39;s body because the rigid panel functions as a deformation-resistant, stabilizing support for the article against the movement of the wearer.  
         [0028]     The embodiment of the invention wherein each of the engaging portions may be formed by securing a hook member having a plurality of hook elements projecting from a sheet-like backing to a zone of the rigid panel defining the backing for the engaging portion allows the hook member to be selected from those well known in the art. In addition, this embodiment allows the zone of the panel serving as the backing for the engaging portion to have a relatively low stiffness since the hook member has a relatively high stiffness.  
         [0029]     The embodiment of the invention wherein each of the engaging portions may be formed by coating a zone of the rigid panel defining the backing for the engaging portion with a pressure-sensitive adhesive allows the engaging portion to be formed at a low cost merely by coating the predetermined zone with a pressure-sensitive adhesive.  
         [0030]     The embodiment of the invention wherein each of the landing portions may be formed from a fibrous texture defining the sleeve and functioning as the loop elements allows the landing portion to be formed at a low cost without using a relatively expensive loop member.  
         [0031]     The embodiment of the invention wherein each of the landing portions may be formed by securing a loop member having a plurality of loop elements projecting from a sheet-like backing to the sleeve allows the pocket to be formed from a material selected from a wide range of materials so far as the pocket can be formed by the selected material.  
         [0032]     The embodiment of the invention wherein each of the inserts may have a stiffness value in a range of 0.05N/cm to 2N/cm as measured by the Taber&#39;s method facilitates it to introduce the insert into the pocket and eliminates an apprehension that the wearer might feel any discomfort due to the stiffness of the insert when the article is worn.  
         [0033]     The embodiment of the invention wherein the elastic means may comprise a pair of elastically stretch- and contractible ear flaps extending outward from the side edges of the first waist region facilitate it to provide means automatically adjust a circumferential waist dimension defined by the first and second waist regions at a reduced cost.  
         [0034]     The embodiment of the invention wherein the first and second waist regions as well as the crotch region may be formed by an absorbent chassis comprising, in turn, a liquid-pervious inner sheet, a liquid-impervious outer sheet and a liquid-absorbent core interposed between these inner and outer sheets makes it possible to provide the article being well capable of absorption and containment. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0035]      FIG. 1  is a partially cutaway perspective view showing a disposable diaper with front and rear waist regions opened along one of laterally opposite side edges and remaining closed along the other side edge;  
         [0036]      FIG. 2  is a perspective view showing said diaper developed with its inner surface opposed to the viewer;  
         [0037]      FIG. 3  is a sectional view taken along the line  3 - 3  in  FIG. 1 ;  
         [0038]      FIG. 4  is a sectional view taken along the line  4 - 4  in  FIG. 1 ; and  
         [0039]      FIG. 5  is a sectional view taken along the line  5 - 5  in  FIG. 1 . 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0040]      FIGS. 1 and 2  show an open-type disposable diaper as a specific embodiment of the invention. The diaper includes an absorbent chassis  1  and a fastening means  2 . The chassis  1  has a front waist region  3 , a rear waist region  4  and a crotch region  5  extending between these waist regions  3 ,  4 . The fastening means  2  comprise a pair of engaging fasteners  6 A respectively attached to laterally opposite side edges of the rear waist region  4  and a pair of landing fasteners  6 B respectively attached to laterally opposite side zones of the front waist region  3  on its surface facing the wearer&#39;s garment. The chassis  1  may be assembled by anchoring the engaging fasteners  6 A onto the landing fasteners  6 B and thereupon a waist-opening  7  and a pair of leg-openings  8  are defined.  
         [0041]     The chassis  1  comprises a liquid-pervious inner sheet  9 , a liquid-impervious outer sheet  10 , a liquid-absorbent core  11  interposed and joined between these two sheets  9 ,  10  preferably by means of hot melt adhesives (not shown) intermittently applied thereto, and a pair of stretchable ear flaps  19  extending outward from the respective side edges of the rear waist region  4 . The inner and outer sheets  9 ,  10  respectively include side and end flaps  13 ,  14  extending outward beyond a peripheral edge of the core  11 .  
         [0042]     The chassis  1  is provided with tape-like elastic members  15  attached thereto contractibly along the end flaps  14  which define the waist-opening  7  and with a plurality of strand-like elastic members  16  attached thereto contractibly along outer sides of the respective side flaps  13  which define the leg-openings  8 . These elastic members are secured in a stretched state thereof within the side flaps  13  and the end flaps  14 , respectively, by means of hot melt adhesives (not shown) so that, upon being relieved of tension, these elastic members may be free to contract and thereby to form the respective flaps with gathers.  
         [0043]     The chassis  1  further includes a pair of barrier cuffs  17  extending in parallel to each other in a longitudinal direction of the chassis  1 . The respective barrier cuffs  17  have proximal edges  17   a  joined to upper surfaces of the respective side flaps  13  in the vicinity of the side edges of the core  11  by means of hot melt adhesives or a welding means (not shown). Distal segments  17   b  of the barrier cuffs  17  which are contiguous to the proximal edges  17   a  are elasticized in a longitudinal direction thereof. Each of these distal segments  17   b  is elasticized by at least one elastic member  18  attached in a stretched state to the cuff  17  along its distal edge  17   c.    
         [0044]     As has already been described, the chassis  1  still further includes the pair of stretchable ear flaps  19 . These ear flaps  19  respectively have proximal ends  19   a  joined to transversely opposite lateral zones of the rear waist regions  4  by means of hot meld adhesives or a welding means (not shown) and distal segments  19   b  which are contiguous to the proximal ends  19   a . A part of the rear waist region  4  defined between the ear flaps  19  is elastically stretched as these ear flaps  19  are pulled outward against a contractile force thereof. In this way, such a part of the rear waist region  4  is brought in close contact with the diaper-wearer&#39;s skin when the diaper is worn.  
         [0045]     Referring to  FIG. 3 , each of the engaging fasteners  6 A includes a backing  20  in the form of an elongate, a stiff panel  20  folded to define backing segments  20   a ,  20   b  wherein the backing segment  20   b  slants at a given angle, preferably at the angle in a range of 3° to 30° with respect to the backing segment  20   a . The backing segment  20   b  can be pressed into contact with the backing segment  20   a but elastically detached therefrom as the backing segment  20   b  is relieved of such a pressing force. The engaging fastener  6 A may be secured to the associated ear flap  19  by pinching the ear flap  19  between a backing segment  20   c  and a protector  30 , followed by assembling them together using suitable adhesives or a welding means (not shown) Stapling or riveting also may be used to assemble them together.  
         [0046]     A hook member  21  having a plurality of hook elements  21   b  projecting from a backing  21   a  may be secured to the backing segment  20   a  forming a part of the engaging fastener  6 A by means of suitable adhesives (not shown) and thereby an engaging means  22  may be formed. To the backing segment  20   b  forming the other part of the engaging fastener  6 A, in turn, a smooth sheet member  23  having a ground color different from that of the backing segment  20   b  and serving as a shape retaining means may be integrally joined by means of suitable adhesives (not shown) and thereby an insert  24  may be formed.  
         [0047]     Referring now to  FIG. 4 , each of the landing fasteners  6 B is formed by a sleeve  25  and a pocket  26 . The pocket  26  opens outward with respect to the associated side edge of the front waist region  3 . The sleeve  25  is formed from a flexible sheet and secured to the outer sheet  10  facing the wearer&#39;s garment in the front waist region  3  by means of suitable adhesives or a welding means (not shown). A loop member  27  having a plurality of loop elements  27   b  projecting from a backing segment  27   a  is secured to an upper surface of the sleeve  25  by means of suitable adhesives (not shown). Assumed that the sleeve  25  comprises a fibrous or reticular webwork, the loop elements  27   b  can be formed utilizing such a webwork itself. In this manner, the sleeve  25  is formed on its upper surface with landing means  28  with which the engaging means  22  can be releasably engaged.  
         [0048]     When it is desired to connect the front and rear waist regions  3 ,  4  with each other, as illustrated in details in  FIG. 5 , the insert  24  of the engaging fastener  6 A may be introduced into the pocket  26  of the landing fastener  6 B through the opening of the pocket  26  and then the engaging means  22  of the engaging fastener  6 A may be pressed against the landing means  28  so as to engage the latter. In order to ensure that the insert  24  can be smoothly introduced into the pocket  26 , the insert  24  preferably has a stiffness value in a range of 0. 05N/cm to 2N/cm as measured by the Taber&#39;s method.  
         [0049]     While not illustrated in details, the hook member  21  constituting the engaging means  22  may be replaced by a pressure-sensitive adhesive. In this case, the pressure-sensitive adhesive is protectively covered with a release paper. It is also possible that the engaging means  22  is formed on its outer end with a finger-grip tab.  
         [0050]     The inner sheet  9 , the outer sheet  10  and the core  11  may be formed using materials commonly used for disposable diapers of prior art. Particularly, the inner sheet  9  may be formed from a fibrous nonwoven fabric, a porous plastic film or the like, the outer sheet  10  may be formed from a moisture-pervious plastic film or a laminate of such a film and a fibrous nonwoven fabric and the core  11  may be formed from a mixture of fluff pulp and super-absorbent polymer particles or the like.  
         [0051]     The elastic members  15 ,  16 ,  18  also may be formed from materials commonly used for disposable diapers of prior art, for example, a natural rubber, a synthetic rubber, an urethane foam or the like.  
         [0052]     The ear flap  19  may be formed using a stretchable nonwoven fabric of prior art. While it has previously been described that the elastically stretchable zone of the waist region is defined between a pair of the ear flaps  19 , it is possible to replace the ear flaps  19  by a stretchable nonwoven fabric forming this zone having a desired width dimension and provided with a plurality of thread-like elastic members spaced one from another.