Water-degradable paper sheet, and tube for a paper roll consisting of such a sheet
A water degradable paper sheet has a basis weight of 80 to 400 g/m 2 and is dry-formed from paper fibers bound together by a water-soluble binder including starch, the amount of binder in the sheet being 30 to 70%. Additionally, a tube is formed by a cylinder having a wall that includes at least one dry-formed paper sheet including paper fibers bound together by a water-soluble binder.
1. A roll tube composed of a wound strip of sheet material, the roll tube comprising:
a cylinder, a wall of the cylinder comprising at least one dry-route paper sheet comprising paper fibres bonded to one another by a water-soluble binder comprising starch, the amount of the binder in the sheet being between 30 and 70% by weight.
2. The roll tube according to claim 1 , wherein a disintegration time of the roll tube in water is between 10 and 40 seconds.
3. The roll tube according to claim 1 , wherein the roll tube is formed solely of dry-route paper.
4. The roll tube according to claim 1 , wherein the wall of the cylinder is made of one or more layers of dry-route paper.
5. The roll tube according to claim 1 , wherein the wall of the cylinder is formed of one or more layers of dry-route paper with a unitary thickness of between 0.3 and 2 mm.
6. The roll tube according to claim 1 , wherein the binder further comprises sucrose.
7. The roll tube according to claim 2 , wherein the disintegration time of the roll tube in water is between 12 and 20 seconds.
8. The roll tube according to claim 5 , wherein the wall of the cylinder is formed of one or more layers of dry-route paper with a unitary thickness of between 0.4 and 1.2 mm.
9. A roll formed by winding a strip of sheet material around a tube, the roll comprising:
a cylinder, a wall of the cylinder comprising at least one dry-route paper sheet comprising paper fibres bonded to one another by a water-soluble binder comprising starch, the amount of the binder in the sheet being between 30 and 70% by weight.
10. A roll according to claim 9 , wherein the sheet material is cellulose wadding.