1473838 Laminates KARL KROYER ST. ANNE'S Ltd 26 July 1974 [23 Aug 1973] 40074/73 Heading B5N A dry-laid web or cellulosic fibrous material is moistened and formed into a consolidated web by dry-laying cellulosic fibres to form a mat upon a supporting surface, forming a sheet of aqueous cellulosic fibrous stock, combining the sheet of stock with the mat and consolidating the combination of dry-laid fibres and aqueous stock by subjecting it to heat and pressure. The stock may be directed in sheet form on to the mat from a slice and the combination consolidated by passage around a heated cylinder having pressure rollers co-operating therewith. Alternatively the stock may be formed into a web by a wet-forming technique on an auxiliary forming band before it is combined with the mat. The stock may have a solids content of 10-15% by weight and the moisture content of the combination may be about 30% by weight. In Fig. 2 dry cellulosic fibres mixed with 5% by weight of starch binder are conveyed in an air stream from dispenser heads 11 on to the upper surface of endless wire supporting surfaces 10 to form a mat thereon. A wet-laid fibrous web formed on auxiliary forming wire 21 in cylinder mould device 20 is transferred at roll 22 on to the mat with the aid of vacuum box 23 and the combination consolidated by pressing against consolidating cylinder 15 using pressure rolls 16. The consolidating cylinder may have a temperature of at least 150‹ F. and each pressure roll may be applied with a pressure of at least 150 p.l.i. In an alternative arrangement the wet-laid fibrous web may be transferred to the consolidating cylinder before the dry-laid fibrous web is applied thereto. When multiply products are required two units of the type shown in Fig. 2 may be employed in back-toback relationship so that the wet-laid webs form the outer liners of the product and the dry-laid webs form the inner plies.
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