Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – With formation of web or article
Patent
1997-10-07
2000-02-15
Nguyen, Dean T.
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
With formation of web or article
162 56, 162 92, 162 97, 162 99, 162135, 162261, D21H 1112, D21H 2322
Patent
active
060248327
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
This invention relates to a method for producing extensible paper and a plant for implementing the method.
DESCRIPTION OF THE PRIOR ART
U.S. Pat. No. 3,454,463 discloses a method of subjecting newsprint paper to controlled compressive shrinking including the features of passing the wire side of a web in contact with the moving smooth surface of a mechanical compactor and shrinking the newsprint web to a value substantially above the desired value and then stretching the web to the desired value.
EP-A-0631014 discloses a process for making soft tissue products.
An object of the invention is to provide a method enabling paper to be produced with a high degree of strength while at the same time with an extensibility both in the longitudinal direction and in the transverse direction of practically the same order of magnitude.
A further object of the invention is to provide a method enabling paper to be produced with a continuous plant.
A further object of the invention is to provide a method enabling producing paper with smooth surface in order to improve its printability characteristics.
BRIEF SUMMARY OF THE INVENTION
These and further objects which will be apparent from the ensuing description are attained according to the invention by a method for producing extensible paper, comprising the following stages: cloth with consequent reduction of the water percentage by gravity and vacuum, content of between 15% and 65%, 10%-8%, unit to obtain a pulp having a degree of beating of at least 30.degree. SR, which one is of hard material comprising circunferential surface ribs and driven at greater speed, and the other is of soft material with a smooth surface and driven at lesser speed.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention is described hereinafter with reference to the accompanying drawings, in which:
FIG. 1 is a schematic view of a plant for implementing the method of the invention;
FIGS. 2, 3, 4 and 5 are schematic views showing different rollers used in the preforming stage;
FIG. 6 is a schematic view showing the rollers used in the compaction stage .
DESCRIPTION OF PREFERRED EMBODIMENTS
As can be seen from the figures, the plant for producing extensible paper comprises essentially a high density kneader 1 consisting substantially of a cylindrical tank 2 with an inverted frusto-conical base and internally housing a conical impeller 3 comprising on its surface a helical projection.
The kneader 1 is connected to a storage vat 4 provided with a stirrer 5 and connected to a beating station 6 formed from beating units 7 of lava disc type alternating with storage chests 8. The exit from the last beating unit 7 is connected to a further high density beating unit 7' of perforated ring type connected to a storage vat 9 communicating with a flow chest 10 feeding a station 11 in which the paper web is formed. This station comprises a cloth 12 taut between two return rollers 13 and arranged to subject the pulp of water and fibrous raw materials to progressive water extraction by means of gravity and vacuum.
The downstream end of the paper web formation station 11 leads to a pressing station 14, downstream of which there are provided an impregnation station 23 and a successive preforming station 15.
Downstream of the preforming station 15 there is provided a drying station 16 of hot roller type which ensures a constant moisture content of the paper web of between 15% and 65%, preferably 50%, and a subsequent compaction station 17 comprising pairs of counter-rotating rollers of different type and surface consistency, driven at different speeds and able to compact the web both longitudinally and transversely. In particular the upper roller 37 of each pair is of metal, comprises a plurality of surface circumferential ribs 38 and rotates at greater speed than the corresponding lower roller 36 which is in rubber and has its surface smooth.
The exit of the compaction station 17 is connected to a further drying station 18, which is connected to a glazin
REFERENCES:
patent: 3290209 (1966-12-01), Ihrman
patent: 3454463 (1969-07-01), Welsh
Cariolaro Norberto
Trani Giorgio
Giorgio Trani Cartiere Cariolaro S. p. A.
Nguyen Dean T.
LandOfFree
Method and apparatus for producing extensible paper does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for producing extensible paper, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for producing extensible paper will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1902751