GB1439289A - Disposable diaper - Google Patents

Abstract

1439289 Laminates JOHNSON & JOHNSON 29 Aug 1973 40641/73 Heading B5N [Also in Division A5] A multi-layer diaper comprises a porous facing layer 16 in the form of a nonwoven web of staple length fibres and short cellulosic fibres at an overall concentration of staple length fibres from 2-55% and an overall concentration of short fibres from 45-98% by weight, the web having an outer major face 15 charactterized by a concentration of staple length fibres in excess of said overall concentration and an inner face 17 characterized by a concentration of short fibres in excess of said overall concentration; a highly porous loosly compacted cellulosic fibrous batt 14 in face-to-face juxtaposition with the inner face 17 of the facing layer; and a water-impervious backing sheet 12 adhered to the outer surface of the batt. By short fibres is meant fibres less than “ inch. in length and by staple fibres, fibres greater than “ inch in length and preferably between ¢ and 2¢ inches in length. The transition in concentration of each type of fibre between the faces 17, 15 is substantially uniform. The batt 14 may have a densified layer 18 integral therewith, the layer 18 including spaced parallel thickened portions 19 extending through the thickness of the batt. The facing layer 16 and backing sheet 12 are coextensive and secured together by adhesive or heat-sealing. The diapers are formed by feeding compacted wood pulp 41 to a grinding mill 42 where short fibres are formed and blown on to a belt 43, the resultant layer 44 being compacted by rolls 46, 47. Moisture is sprayed on to the web at 48, the web then passing between rolls 49 whereby a paper-like skin 51 is formed on its upper surface. The thickned portions 19 are formed on passage through roll 53 and embossing roll 52 having spaced circumferential projections 54. A cutter 56 divides the web into individual batts 14. Polyethylene film 12 is fed from roll 58 and supplied with adhesive at 59. The facing layer is formed by feeding a supply of short cellulosic fibres 70 and staple fibres 71 to a mixing apparatus 72, comprising two rotating lickerins, which suspends the fibres from each source in separate gas-streams directed towards each other and combining to form a single stream wherein the fibres from each stream cross over one another to form the facing layer. The web 73 passes from apparatus 72 to station 75 where a bonding agent is supplied and is thereafter dried on passing between rollers 76. The web then passes upwardly for bonding with the batts 14 and film 12. Individual diapers are cut off by cutter 62.