Patent GB-1063217-A (GB)
Title: Papers and non-woven fabrics containing mixed spun fibres
IPC: D04H1/54
Filed: 1963-08-15
Abstract: A fibre is obtained by spinning a mixture of viscose with a high-molecular-weight substance capable of swelling in water, that is polyvinyl alcohol, hemicellulose, cyanoethylcellulose or carboxymethyl-cellulose.  Such a fibre may be a flat fibre, i.e. one having a cross-section of which the width is more than five times the thickness, or a hollow flat fibre.  Hollow fibres may be made by adding carbonates or other suitable foaming agents to e.g. viscose and spinning the solution under suitable conditions. Paper or non-woven fabric may be made from the fibres described, especially flat fibres.  A synthetic resin may be incorporated for increasing the strength of such paper or non-woven fabric. Specified resins include polyvinyl alcohol derivatives, polyacrilamide derivatives, starch derivates, urea formaldehyde resins, and melamine formaldehyde resins.  Flat regenerated cellulose fibres containing a high mollecular weight substance capable of swelling in water may be used to obtain strong paper or non-woven fabrics without adding adhesive agents or binding fibres; but by using fibres having a flat section, or otherwise, mixed with other fibres, e.g. conventional regenerated cellulose fibres, synthetic fibres, and inorganic fibres, enhanced papers may be obtained.  Wood fibre and bast fibre may be so used as may water soluble polyvinyl alcohol fibre.  In Example 1 mixed spun regenerated cellulose fibre containing 30% of polyvinyl alcohol was dispersed into water, beaten by a suitable beater and dispersing agent added.  A paper was formed therefrom and dried at 105 DEG C. Conventional regenerated cellulose fibre (not p  containing polyvinyl alcohol) does not form a paper under the same conditions.  In Example 2 the same fibre was used as in Example 1 and dispersing agent a Illegible data ded to it without beating.  Paper is made from the mixture and the wet paper sheet pressed and dried at 105 DEG C.  In Example 3 mixed spun regenerated cellulose fibre containing 15% of carboxymethyl cellulose was beaten by beater in the same manner as in example 1 and mixed in a ratio of 1:2 with a conventional strong regenerated cellulose staple fibre.  A paper was made from the mixture and dried at 105 DEG C.  In Example 4 a mixed spun flat regenerated cellulose fibre containing 40% of polyvinyl alcohol is used to make paper in the manner of example 2.  By comparison, an ordinary flat regenerated cellulose staple fibre containing no polyvinyl alcohol could not be made into paper under the same conditions.  In Example 5 a mixed spun flat regenerated cellulose fibre containing 30% of polyvinyl alcohol was used to make paper by a similar manner to that described in Example 2.  In Example 6, water soluble polyvinyl alcohol fibre containing 15% of regenerated cellulose was mixed with an ordinary strong regenerated cellulose staple fibre in a ratio of 3:7 and the mixture used to make papers and dried at 105 DEG C.  In example 7 a mixed spun regenerated cellulose fibre containing 20% polyvinyl alcohol was arranged by two sets of garnet machines and the fibre, clamped by means of wire gauze, was dipped into water, pressed, dried by a drier and heat treated by hot air at 180 DEG C. for three minutes.  The strength of the non-woven fabric of regenerated cellulose fibre thus produced, is found much superior to that of ordinary non-woven fabrics made of regular regenerated cellulose fibres attached together by means of a conventional synthetic rubber latex.