Method for providing a wire for forming a patterned fibre web, a wire and a patterned fibre web produced thereby

Abstract

A method for providing a wire for forming a patterned fiber web, a wire which has been provided by means of the method according to the invention and a patterned fiber web formed on the wire ( 100 ) according to the invention, which comprises a plurality of threads ( 101, 102, 103, 104, 105, 106 ) arranged in a wire structure with a plurality of drainage opening ( 107, 108, 109 ) and a patterning area ( 110 ) substantially in the plane of the wire, intended for the forming. In the method a number of the threads ( 103, 104, 105 ) are given a permanent deformation for forming one or several pattern creating surfaces ( 111 ) within the patterning area ( 110 ) at the forming. The invention may be applied in relation to production of soft tissue paper, wet pressed non woven materials, air laid non woven materials, or at the production of hydraulically patterned or entangled non woven materials. The patterned fiber webs may be converted to toilet paper, paper towels, household paper, facial tissues, napkins, wet napkins, handkerchiefs, dry towels for infants, flannels, wipes for industrial cleaning and the like. The fiber web or the webs may also be converted to or be a part of other sanitary articles, such as nappies, sanitary napkins, panty liners and incontinence guards.

1 . A method for providing a wire for forming a patterned fibre web, said wire ( 100 ) comprising a plurality of threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) arranged in a wire structure with a plurality of drainage openings ( 107 ,  108 ,  109 ) and a patterning area ( 110 ) substantially in the plane of the wire, intended for the forming, wherein a number of the threads ( 103 ,  104 ,  105 ) are given a permanent deformation for forming one or several pattern creating surfaces ( 111 ) at the forming within the patterning area ( 110 ), and the index of density (A0−Ad)/A0 of the wire ( 100 ) within the pattern creating surfaces ( 111 ) is between 0 and 1, whereby A0 is the area of an individual wire opening before the deformation and Ad is the area after the deformation.  
     
     
         2 . A method as claimed in  claim 1 , wherein the deformation is carried out so that substantially all threads within the rim sections ( 112 ,  113 ) of the wire ( 100 ) outside the patterning area ( 110 ) are not deformed.  
     
     
         3 . A method as claimed in  claim 1 , wherein the deformation gives the pattern creating surfaces ( 111 ) a pattern report with a division deviating from the weaving report of the wire ( 100 ) or a multiple thereof.  
     
     
         4 . A method as claimed in  claim 1 , wherein the deformation gives the pattern creating surfaces ( 111 ) an extension pattern being substantially independent of the wire structure.  
     
     
         5 . A method as claimed in  claim 1 , wherein the deformation is completed while a majority of the threads ( 103 ,  104 ,  105 ) are still moveable relative each other within the pattern creating surfaces ( 111 ).  
     
     
         6 . A method as claimed in  claim 1 , wherein the threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) at least comprise a thermoplastic polymer material with at least one softening temperature, and wherein the deformation is carried out at a temperature lower than the softening temperature.  
     
     
         7 . A method as claimed in  claim 1 , wherein the threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) at least comprise a thermoplastic polymer material with one softening temperature, and wherein the deformation is carried out at a temperature close to or higher than the softening temperature.  
     
     
         8 . A method as claimed in  claim 6 , wherein the polymer material comprises polyester or polyamide.  
     
     
         9 . A method as claimed in  claim 7 , wherein the polymer material comprises polyester or polyamide.  
     
     
         10 . A method as claimed in  claim 1 , wherein the threads ( 101 ,  102 ,  103 ,  104 ,  106 ) comprise bi-component fibres or filaments of at least a first polymer with a first softening temperature and a second polymer with a second softening temperature, which is lower than the said first softening temperature.  
     
     
         11 . A method as claimed in  claim 1 , wherein the deformation occurs with assistance of at least one embossing element ( 114 ) and a holder-on ( 115 ), which form a press nip which the wire ( 100 ) runs through.  
     
     
         12 . A method as claimed in  claim 11 , wherein the embossing element ( 114 ) and/or the holder-on ( 115 ) traverse in the cross direction (CD) of the wire, whereby the wire ( 100 ) is intermittently lead in the machine direction (MD) between said embossing element and said holder-on.  
     
     
         13 . A method as claimed in  claim 1 , wherein the deformation occurs after or in relation to heating up of at least a number of the threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) with the assistance of ultrasonic, one or several heated rolls, laser, microwaves, induction, or hot air.  
     
     
         14 . A wire for forming a patterned fibre web, said wire ( 100 ;  300 ;  400 ;  500 ) comprising a plurality of threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) arranged in a wire structure with a plurality of drainage opening ( 107 ,  108 ,  109 ) and a patterning area ( 110 ) substantially in the plane of the wire, intended for the forming, wherein a number of the threads ( 103 ,  104 ,  105 ) shows a permanent deformation forming one or several pattern creating surface ( 111 ;  311 ;  411 ;  511 ) at the forming within the patterning area ( 110 ), and wherein a number of the drainage opening within the pattern creating surfaces are at least blocked as a consequence of the deformation for giving a reduced drainage capacity being lesser than the original drainage capacity of the said drainage openings, whereby the drainage capacity of the drainage openings within the pattern creating surfaces shows a substantially infinitely variable distribution of magnitude between the reduced drainage capacity and the original drainage capacity.  
     
     
         15 . A wire as claimed in  claim 14 , wherein the wire ( 100 ) has a first side ( 116 ) intended to be facing a fibre web and an opposite second side ( 117 ), and wherein only the threads within the patterning area on the first side ( 116 ) are permanently deformed, while at least threads in the longitudinal direction (MD) on the second side ( 117 ) of the wire are substantially unaffected of the deformation.  
     
     
         16 . A wire as claimed in  claim 14 , wherein a majority of the pattern creating surfaces ( 111 ) have a minimum dimension between 1 and 2 mm in the plane of the patterning area.  
     
     
         17 . A wire as claimed in  claim 14 , wherein the wire is used as forming wire at wet forming or foam forming of a fibre web, intended for soft tissue paper or a non woven material.  
     
     
         18 . A wire as claimed in  claim 14 , wherein the wire is used as a forming wire at air laying of a fibre web.  
     
     
         19 . A wire as claimed in  claim 14 , wherein the wire is used as a support at hydraulic patterning or entangling at a preformed web.  
     
     
         20 . A wire which has undergone a method according to  claim 1 .  
     
     
         21 . A patterned fibre web, formed on a wire ( 100 ) comprising a plurality of threads ( 101 ,  102 ,  103 ,  104 ,  105 ,  106 ) arranged in a wire structure and a patterning area ( 110 ), whereby the fibre web ( 118 ) at least shows one pattern ( 119 ,  119 ′) deviating from the wire structure, wherein the pattern ( 119 ,  119  ′) has been created by pattern creating surfaces ( 111 ) formed by means of a permanent deformation of a number of the threads ( 103 ,  104 ,  105 ) within the patterning area ( 110 ), and which within the patterning area ( 110 ) comprises first sections with a first basis weight unaffected of the pattern creating surfaces ( 111 ), and second sections with a second basis weight affected of the pattern creating surfaces, which is lesser than the first basis weight, and wherein the pattern ( 119 ,  119  ′) comprises one or several infinitely variable changeovers from the first basis weight to the second basis weight.  
     
     
         22 . A patterned fibre web as claimed in  claim 21 , wherein the pattern ( 119 ,  119  ′) has a division deviating from the weaving report of the wire ( 100 ) or a multiple thereof.  
     
     
         23 . A patterned fibre web as claimed in  claim 21 , wherein a pattern ( 119 ,  119  ′) is formed substantially independent of the wire structure.  
     
     
         24 . A patterned fibre web as claimed in  claim 21 , wherein the fibre web ( 118 ) is wet formed or foam formed.  
     
     
         25 . A patterned fibre web as claimed in  claim 21 , wherein the fibre web is air laid.  
     
     
         26 . A patterned fibre web as claimed in  claim 21 , wherein the fibre web is hydraulically patterned or entangled.  
     
     
         27 . A patterned fibre web wherein the pattern ( 119 ,  119  ′) has been created by means of forming and/or patterning on a wire ( 100 ;  300 ;  400 ;  500 ) according to claim  14 .