Process for the manufacture of multi-ply tissue

Abstract

The invention relates to a process for the manufacture of a multi-ply tissue comprising at least two plies. The process comprises steps of mechanically refining a first slurry of fibers wherein the fibers have an average length of at least 2 mm; mixing the refined slurry with a second slurry of fibers, providing an embryonic web upon a foraminous surface, removing water from the embryonic web to form a ply; and juxtaposing at least two plies to form the multi-ply tissue.

What is claimed is:  
     
         1 . A process for making the multi-ply tissue comprising the steps of: 
 mechanically refining a first slurry of fibers wherein the fibers have an average length of at least 2 mm;    mixing the refined slurry with a second slurry of fibers, the average length of the fibers of the second slurry being shorter than the average length of the fibers of the first slurry;    providing a embryonic web upon a foraminous surface, the composition of fibers in the embryonic web being substantially homogeneous throughout the thickness of the web;    removing water from the embryonic web to form a ply; and    juxtaposing at least two plies to form the multi-ply tissue.    
     
     
         2 . A process according to  claim 1  wherein a substantial proportion of the fibers of the first slurry comprises softwood fibers, and a substantial proportion of the fibers of the second slurry comprises hardwood fibers.  
     
     
         3 . A process according to  claim 1  wherein the ratio of long softwood fibers to shorter hardwood fibers is greater than 60:40, and preferably about 70:30.