Patent Publication Number: US-2023149222-A1

Title: Washable absorbent garment

Description:
FIELD OF THE INVENTION 
     The present invention relates to absorbent garment for the absorption and retention of liquids, and more particularly to washable and reusable absorbent garments. 
     PRIOR ART 
     Various washable garments having a pant-like configuration and useful as incontinence garments, menstrual garments, training garments, diapers, and the like, are commercially available, as well as being disclosed in various patents. 
     For instance, absorbent garments are commercially available which are machine washable, and thus reusable, having an absorbent pad sewn into the crotch area. 
     U.S. Pat. No. 3,489,149 discloses a menstrual panty having a pocket sewn into the crotch area, the pocket being used for receiving an absorbent disposable menstrual pad. Similarly, U.S. Pat. No. 4,352,356 discloses a urinary incontinence panty having a pouch connected in the crotch area and adapted to receive an absorbent disposable urinary incontinence pad. Another sanitary panty garment with a pocket in the crotch area is disclosed in U.S. Pat. No. 3,613,686. 
     Also, washable absorbent garments are known wherein the absorbent pad is permanently connected to the pant structure. For instance, GB2176692A discloses an absorbent sanitary garment made in the form of knitted polyester material which incorporates a non-removable pad made of brushed polyester which has the appearance of soft felt. The absorbent pad cannot be removed and is made of a material which can be frequently washed. 
     Prior art washable absorbent garments are manufactured by the same techniques uses for manufacturing textiles articles, typically by manually cutting and sewing fabric materials. In the prior art washable absorbent garments, a washable absorbent core is typically sewn to a fabric layer forming a pant-structure and opposite waist sections of the pant-structure are sewn to each other. The typical production rate of prior art washable absorbent garments is in the range of 1 piece/1′. 
     The main problem of the prior art washable absorbent garments is the high use of manual labor, and consequently the very low production rates and the high costs due to the high impact of manpower. 
     OBJECT AND SUMMARY OF THE INVENTION 
     The object of the present invention is to provide a washable absorbent garment which overcomes the problems of the prior art. 
     According to the present invention, this object is achieved by a washable absorbent garment having the features of claim  1 . 
     The claims form an integral part of the disclosure provided here in relation to the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will now be described in detail with reference to the attached drawings, given purely by way of non-limiting example, wherein: 
         FIG.  1    is a perspective view of a washable absorbent garment in an open configuration, 
         FIG.  2    is a plan view of the absorbent garment of  FIG.  1    in the open configuration, 
         FIG.  3    is a schematic cross-section taken along the line III-III of  FIG.  2   , 
         FIGS.  4  and  5    are schematic side views of an apparatus for producing the washable absorbent garment of  FIGS.  1 - 3   , 
         FIGS.  6 - 11    are schematic plan views showing intermediate steps of a method for producing washable absorbent garments, and 
         FIG.  12    is a schematic side view showing an alternative to the part of the apparatus shown in  FIG.  5   . 
     
    
    
     It will be appreciated that the various figures may not be represented on the same scale. It will also be appreciated that in some figures certain elements or components may not be shown for a better understanding. 
     DETAILED DESCRIPTION 
     With reference to  FIGS.  1 - 3    the numeral reference  10  indicates a washable absorbent garment. 
     The washable absorbent garment  10  comprises a back layer  12  of washable fabric forming a pant structure. The back layer  12  has rear and front waist sections  14 ,  16  and a crotch section  18  intermediate between the rear and front waist sections  14 ,  16 . The rear and front waist sections  14 ,  16  are wider than the crotch section  18 , such that in the extended position of  FIGS.  1  and  2    the back layer  12  has substantially an hourglass shape. 
     The back layer  12  is a fabric formed by woven threads which is washable as ordinary textile garments, e.g. swimsuits, underwear, etc. The back layer  12  may be made of any natural or synthetic material used for producing textile articles, e.g. cotton, Lycra®, nylon, polyester, polypropylene, polyamide, elastane, Econyl® etc. and any mixture thereof. In possible embodiments, the back layer  12  may be an elastic fabric made of a mixture of polyamide and elastane, cotton and elastane e.g. 80% polyamide/cotton and 20% elastane. The back layer  20  may have a weight comprised between 100-200 g/m 2 . 
     The crotch section  18  of the back layer  12  has two curved side edges  22  shaped to conform to the legs of the user in the configuration in which the washable absorbent garment  10  is worn. The rear and front waist sections  14 ,  16  of the back layer  12  have respective side edges  24 ,  26  which are joined to each other such that the washable absorbent garment  10  is closed in a pant-like shape and has two leg openings on opposite sides of the crotch section  18 . 
     The side edges  24 ,  26  are joined to each other by welding or by glue. Welding may be ultrasonic welding, laser welding, or mechanical welding. 
     The washable absorbent garment  10  comprises a washable absorbent core  28  permanently fixed in the crotch section  18  of the back layer  12 . The washable absorbent core  28  extends only on the crotch section  18  of the back layer  12  and does not extend on the rear and front waist sections  16 ,  18  of the back layer  12 . 
     The washable absorbent core  28  includes a washable absorbent pad comprising washable superabsorbent fibers. A material suitable for producing the washable absorbent pad  30  may be the one marketed by Technical Absorbents Ltd (UK) under the trade name SAF®. The washable absorbent pad may be formed by needlefelt, thermal bonded, laminated non-woven fibers, formed by polyester, polypropylene and SAF®. The washable absorbent pad may have a weight comprised between 100 and 700 g/m 2  and a thickness comprised between 1 and 7 mm. 
     The washable absorbent core  28  may include an acquisition and diffusion layer (ADL) and a barrier film. The washable absorbent pad may be sandwiched between the acquisition and diffusion layer and the barrier film. The washable absorbent core  28  may have a total weight comprised between 150 and 750 g/m 2  and a total thickness comprised between 1.5 and 8.5 mm. 
     The washable absorbent garment  10  comprises a top layer  30  of washable fabric which covers the washable absorbent core  28 . The top layer  30  may be made of the same raw materials as the fabric forming the back layer  12 . The top layer  30  completely covers the washable absorbent core  28  but does not extend on the rear and front waist sections  16 ,  18  of the back layer  12 . 
     The top layer  30  and the washable absorbent core  28  are permanently joined to the back layer  12  by welding or by glue. 
     An embodiment of an apparatus for producing the washable absorbent garment  10  of the type illustrated in  FIGS.  1 - 3    is shown in  FIGS.  4  and  5    and is indicated by the reference numeral  32 . 
     With reference to  FIG.  4   , the apparatus  32  comprises a first unwinding unit  34  configured for unwinding a first continuous fabric layer  36  from a first reel  38 . The first continuous fabric layer  36  is advanced in a machine direction MD on a conveyor  40 . 
     The apparatus  32  comprises a second unwinding unit  42  configured for unwinding a continuous absorbent tape  44  from a second reel  46 . The continuous absorbent tape  44  may comprise a web of superabsorbent fibers sandwiched between an acquisition and diffusion layer and a barrier layer. Alternatively, an acquisition and diffusion layer and a barrier layer may be applied in-line on opposite sides of a web of superabsorbent fibers unwound from the second reel  46 . The web of superabsorbent fibers may be sandwiched between two soft non-woven layers. 
     The apparatus  32  comprises a first cut-and-slip unit  48  configured for transversally cutting the continuous absorbent tape  44  to form individual absorbent cores  28 . The first cut-and-slip unit  48  is configured for longitudinally spacing from each other the individual absorbent cores  28  and for applying the individual absorbent cores  28  on the first continuous fabric layer  36  in longitudinally spaced positions on the conveyor  40 . 
     The apparatus  32  comprises a third unwinding unit  49  configured for unwinding a second continuous fabric layer  50  from a third reel  52 . The apparatus  32  comprises a second cut-and-slip unit  54  configured for transversally cutting the second continuous fabric layer  50  to form individual top layers  30 . The second cut-and-slip unit  54  is configured for longitudinally spacing from each other the individual top layers  30  and for applying the individual top layers  30  on respective absorbent cores  28  previously applied on the first continuous fabric layer  36  on the conveyor  40 . 
     The apparatus  32  may comprise a glue dispenser  56  configured for applying a discrete pattern of glue on the first continuous fabric layer  36  for permanently attaching by glue the individual absorbent cores  28  and the individual top layers  30  on the first continuous fabric layer  36 . 
     The apparatus  32  comprises a sealing press  58  located at the end of the conveyor  40 , configured for compressing the individual absorbent cores  28  and the individual top layers  30  to the first continuous fabric layer  36 . After the compression, the individual absorbent cores  28  and the individual top layers  30  are permanently fixed by glue to the first continuous fabric layer  36  in longitudinally spaced positions to form a continuous garment tape  59 . 
     Alternatively, the apparatus  32  may comprise a welding unit configured for permanently attaching the individual absorbent cores  28  and the individual top layers  30  on the first continuous fabric layer  36 . The welding unit may be a ultrasonic or mechanical welding unit. 
       FIG.  6    shows a portion of the continuous garment tape  59  formed by individual absorbent cores  28  and individual top layers  30  fixed to the first continuous fabric layer  36 . 
     The apparatus  32  comprises a cutting unit  60  configured for cutting longitudinal side edges of the continuous garment tape  59  as it advances in the machine direction MD along curved profiles shaped to conform to the legs of the user. The cutting unit  60  comprises an anvil roller  62  and a cutting tool  64  cooperating with the outer surface of the anvil roller  62 . The cutting tool  64  may be a laser beam or an ultrasonic horn configured for carrying out a laser or ultrasonic cut of the first continuous fabric layer  36 . The cutting tool  64  may also cut simultaneously side edges of the top layers  30 . 
     The cutting tool  64  may be movable transversally to the machine direction to form, in conjunction with the longitudinal movement of the continuous garment tape  59 , curved cuts which form curved side edges  22  ( FIG.  7   ) of the continuous garment tape  59 . The portions trimmed from the continuous garment tape  59  are collected in a waste collecting channel  65 . The same results could be obtain employing traditional mechanical rotary cutting devices, but with very high limitation with respect to process flexibility and cost. 
     The apparatus  32  comprises a press unit followed by a transverse cutting unit  66  configured to cut the first continuous fabric layer  36  along transverse cutting lines  68  ( FIG.  7   ) to form individual blank absorbent garments  70 .  FIG.  7    shows the continuous garment tape  59  after the longitudinal and transverse cutting steps. 
     The apparatus  32  comprises a transverse folding unit  72  configured for folding the individual blank absorbent garments  70  along respective transverse folding lines, so as to overlap to each other the rear and front waist sections  14 ,  16  of each blank absorbent garment  70 .  FIG.  8    shows a blank absorbent garment  70  after the transverse folding step. 
     With reference to  FIG.  5   , the apparatus  32  comprises a sealing unit  74  which receives the folded blank absorbent garments  70  from the folding unit  72 . With reference to  FIG.  9   , the sealing unit  74  is configured for sealing side edges  24 ,  26  of the rear and front waist sections  14 ,  16  of the blank absorbent garments  70 , to form finished absorbent garments  10 . The sealing unit  74  may be an ultrasonic sealing unit configured for carrying out ultrasonic welding of the overlapped side edges  24 ,  26 . Similar results could be obtained with a laser or mechanical sealing unit. 
     The apparatus  32  may comprise a linear folding unit  76  configured for folding side portions of the finished absorbent garments  10  as shown in  FIG.  10   . 
     The apparatus  32  may comprise a final press unit  78  configured for pressing the folded portions of the finished absorbent garments  10 . 
     The apparatus  32  may comprise a final folding unit  80  configured for carrying out a final folding of the finished absorbent garments  10  as shown in  FIG.  11   . After the final folding unit  80  the finished absorbent garments  10  may be sent to a packaging machine. 
       FIG.  12    shows an embodiment of the apparatus  32  alternative to the embodiment of  FIG.  5   . The elements corresponding to those previously described are indicated by the same reference numbers. 
     In the embodiment of  FIG.  12    the side edges  24 ,  26  of the rear and front waist sections  14 ,  16  of the blank absorbent garments  70  are fixed to each other by glue. The glue dispenser  56  ( FIG.  4   ) may be configured for applying discrete glue layers also on the portions of the first continuous fabric layer  36  which will form the side edges  24 ,  26  of the rear and front waist sections  14 ,  16  of the blank absorbent garments  70 . In the embodiment of  FIG.  12    the apparatus  32  comprises a folding and press unit  82  which receives the folded blank absorbent garments  70  from the folding unit  72 . The press unit  82  is configured to fold and press the side edges  24 ,  26  of the rear and front waist sections  14 ,  16  for glue sealing the side edges  24 ,  26 . 
     The remaining units  76 ,  78 ,  80  of the embodiment of  FIG.  12    are the same as the corresponding units of the embodiment of  FIG.  5   . 
     Embodiments of the method and may have a production rate up to 200 pieces/1′, which is a huge progress as compared to the production rate of prior art washable absorbent products which is about 1 piece/1′. 
     Possible embodiments relate to a method for producing washable absorbent garments ( 10 ), comprising:
         providing a first continuous fabric layer ( 36 ) movable in a longitudinal direction (MD),   providing a continuous washable absorbent tape ( 44 ) containing washable superabsorbent fibers, continuously moving in a longitudinal direction,   transversely cutting said continuous washable absorbent tape ( 44 ) to form individual washable absorbent cores ( 28 ),   spacing from each other in a longitudinal direction said individual washable absorbent cores ( 28 ),   applying said washable absorbent cores ( 28 ) on said first continuous fabric layer ( 36 ) in longitudinally spaced positions over respective glue layers,   providing a second continuous fabric layer ( 50 ) continuously moving in a longitudinal direction,   transversely cutting said second continuous fabric layer ( 50 ) to form individual top layers ( 30 ),   spacing from each other in a longitudinal direction said individual top layers ( 30 ),   applying said individual top layers ( 30 ) over respective washable absorbent cores ( 28 ) on said first continuous fabric layer ( 36 ),   permanently attaching said washable absorbent cores ( 28 ) and said individual top layers ( 30 ) to said first continuous fabric layer ( 36 ) by welding and/or by glue to form a continuous washable garment tape ( 59 ), and   transversely cutting said continuous washable garment tape ( 59 ) to form individual blank absorbent garments ( 70 ).       

     The method may comprise transversely folding said individual blank absorbent garments ( 70 ) and overlapping to each other rear and front waist sections ( 14 ,  16 ) of each of said individual blank absorbent garments ( 70 ), and joining side edges of said rear and front waist sections ( 14 ,  16 ) by welding and/or glue. 
     The method may comprise cutting opposite side edges of said continuous washable garment tape ( 59 ) along shaped profiles while advancing said continuous washable garment tape ( 59 ) in said longitudinal direction. 
     In possible embodiments said opposite side edges of said continuous washable garment tape ( 59 ) may be cut by a mechanical, laser or ultrasonic cutting tool ( 64 ). 
     Possible embodiments relate to an apparatus for producing washable absorbent garments ( 10 ), comprising:
         a first unwinding unit ( 34 ) configured for unwinding a first continuous fabric layer ( 36 ) from a first reel ( 38 ),   a second unwinding unit ( 42 ) configured for unwinding a continuous washable absorbent tape ( 44 ) from a second reel ( 46 ),   a first cut-and-slip unit ( 48 ) configured for transversally cutting the continuous washable absorbent tape ( 44 ) to form individual washable absorbent cores ( 28 ), wherein the first cut-and-slip unit ( 48 ) is configured for longitudinally spacing from each other the individual absorbent cores ( 28 ) and for applying the individual absorbent cores ( 28 ) on the first continuous fabric layer ( 36 ) in longitudinally spaced positions,   a third unwinding unit ( 49 ) configured for unwinding a second continuous fabric layer ( 50 ) from a third reel ( 52 ),   a second cut-and-slip unit ( 54 ) configured for transversally cutting the second continuous fabric layer ( 50 ) to form individual top layers ( 30 ), wherein the second cut-and-slip unit ( 54 ) is configured for longitudinally spacing from each other the individual top layers ( 30 ) and for applying the individual top layers ( 30 ) on respective absorbent cores ( 28 ) previously applied on the first continuous fabric layer ( 36 ),   an ultrasonic welding unit or a glue dispenser ( 56 ) configured for permanently attaching by ultrasonic welding or by glue the individual absorbent cores ( 28 ) and the individual top layers ( 30 ) on the first continuous fabric layer ( 36 ).       

     The apparatus may comprise a side cutting unit ( 60 ) configured for cutting longitudinal side edges of a continuous garment tape ( 59 ) advancing in a longitudinal direction and a transverse cutting unit ( 66 ) configured to cut the continuous garment tape ( 59 ) along transverse cutting lines ( 68 ) to form individual blank absorbent garments ( 70 ). 
     The apparatus may comprise a transverse folding unit ( 72 ) configured for folding the individual blank absorbent garments ( 70 ) along respective transverse folding lines, and a sealing unit ( 74 ) configured for sealing side edges ( 24 ,  26 ) of the folded blank absorbent garments ( 70 ). 
     Of course, without prejudice to the principle of the invention, the details of construction and the embodiments can be widely varied with respect to those described and illustrated, without thereby departing from the scope of the invention as defined by the claims that follow.