Glazed paper webs
Provided is a process for preparing a smooth and glossy surfaced paper web. The process comprises subjecting the paper web to shear by using calender rolls driven at different speeds or calender rolls with different diameters. The resulting paper has a totally different structure than the original paper, as it has a much smaller void structure and a much higher degree of bonding between the elements of the sheet. The process is particularly applicable to improving the electrical insulation properties of an aramid paper web.
1 . A process for preparing a paper web having a glossy surface, wherein the paper web is subjected to sufficient shear by at least two calender rolls to create the glossy surface on the paper web, and the shear is imparted by using at least two calender rolls at different speeds and/or at least two calender rolls having different diameters.
2 . The process of claim 1 , wherein the shear is effected by using at least two calender rolls at different speeds.
3 . The process of claim 1 , wherein the shear is effected by using at least two calender rolls having different diameters.
4 . (canceled)
5 . A paper comprised of aramid fibers which has a reduced pore structure achieved by subjecting an aramid paper to shear.
6 . The paper of claim 5 , wherein the paper is subject to shear by treating the paper with a glazer.
7 . A paper comprised of aramid fibers which has a reduced pore structure whereby the structure is achieved by subjecting an aramid paper to shear by treating the paper with a shear calender in accordance with the process of claim 1 .
8 . The paper of claim 7 , wherein the paper further comprises aramid fibrid.
9 . The paper of claim 5 , wherein the paper further comprises aramid fibrid.
10 . A process for reducing the pore structure of a paper comprised of aramid fibers, wherein a paper comprised of aramid fibers is subjected to shear.
11 . The process of claim 10 , wherein the paper is subjected to shear at ambient temperatures.
12 . The process of claim 10 , wherein a glazer is used to subject the paper to shear.
13 . The process of claim 10 , wherein the shear is imparted to the paper by using at least two calender rolls as different speeds and/or at least two calender rolls having different diameters.
14 . The process of claim 13 , wherein the shear is effected by using at least two calender rolls at different speeds.
15 . The process of claim 13 , wherein the shear is effected by using at least two calender rolls having different diameters.