Method of making a compact roll of absorbent paper
A roll of wiping paper is obtained by winding a sheet of multi-ply absorbent paper around a core. The sheet includes at least a first and a second ply of absorbent paper, each with a grammage of between 15 and 30 g/m 2 and at least one of the plies incorporating a wet strength additive. The thickness of the sheet Ep being between 0.02 and 0.07 cm, the diameter of the core being less than 3.5 cm, the diameter of the roll being between 4.5 cm and 11 cm for a volume V of absorbent paper per unit length of the roll, and the absorbency A of the sheet in cm 3 of water per gram of paper being greater than 6 cm 3 /g. The ratio E=A/(Ep*V) of the roll is greater than or equal to 3.2.
1. A method for manufacturing a sheet forming a roll of wiping paper comprising the following steps:
a. providing first and second strips of paper, each strip having first protuberances, the first and second strips being arranged relative to each other so that (i) the first protuberances of the first strip face the first protuberances of the second strip and (ii) all the first protuberances of the first strip are aligned with corresponding cavities in the second strip, a shape of the first protuberances of the first strip being substantially the same as a shape of the first protuberances of the second strip,
b. embossing the first strip on an embossing roll which has protrusions by applying a rubber roll to form a raised marking on the first strip, the raised marking being formed on a same side of the first strip as the first protuberances of the first strip,
c. applying an adhesive to the raised marking formed on the first strip,
d. placing the second strip directly on the first strip whilst the first strip is being held on the embossing roll, and
e. applying a marrying roll to the first and second strips to directly join the first and second strips together along glued joining zones corresponding to the raised marking formed on the first strip,
wherein the pressure applied by the rubber roll and the pressure applied by the marrying roll allow the first and second strips to be joined together along the glued joining zones without protuberances being formed on the face of the sheet against which the marrying roll is applied.
2. The method of claim 1 , wherein a height of the raised marking on the first strip is less than a thickness of the sheet such that the glued joining zones do not form any unevenness on a surface of the sheet.
3. The method of claim 1 , wherein the glued joining zones take up less than 15% of the surface area of the sheet.
4. The method of claim 1 , wherein a thickness of the glued joining zones is less than a thickness of the sheet.
5. The method of claim 1 , wherein when the first strip comes into contact with the second strip, at least some of the first protuberances of the first strip are nested between the first protuberances of the second strip.
6. The method of claim 5 , wherein when the first strip comes into contact with the second strip, at least 15% of the first protuberances of the first strip are nested between the first protuberances of the second strip.
7. The method of claim 1 , wherein at least one of the first strip and the second strip has a grammage of between 15 and 30 g/m 2 .
8. The method of claim 1 , wherein at least one of the first strip and the second strip incorporates a wet strength additive.
9. The method of claim 1 , wherein the sheet has a thickness between 0.02 and 0.07 cm.
10. The method of claim 1 , wherein the sheet has a thickness between 0.03 and 0.06 cm.
11. The method of claim 1 , wherein an absorbency of the sheet in cm 3 of water per gram of paper is greater than 6 cm 3 /g.
12. The method of claim 1 , wherein an absorbency of the sheet in cm 3 of water per gram of paper is less than 16 cm 3 /g.