Conductive webs
View Patent ↗Conductive nonwoven webs are disclosed. The nonwoven webs contain pulp fibers combined with conductive fibers. In one embodiment, the webs are made in a wetlaid tissue making process.
1. A process for producing a conductive paper web comprising:
depositing an aqueous suspension of fibers onto a porous forming surface to form a wet web, the aqueous suspension of fibers comprising pulp fibers and conductive fibers, the conductive fibers comprising carbon fibers, the carbon fibers being present in the wet web in an amount of at least about 2% by weight based upon the total fiber weight;
placing the wet web onto a surface of a rotating heated Yankee dryer drum and drying the web;
removing the dried web from the surface of the Yankee dryer drum without creping the web; and
wherein the forming surface includes areas having substantially no porosity, the formed wet web including non-conductive zones corresponding to where the areas are located on the forming surface.
2. A process as defined in claim 1 , further comprising the step of applying a release agent to the surface of the Yankee dryer drum for facilitating removal of the dried web from the surface.
3. A process as defined in claim 1 , wherein the aqueous suspension of fibers is deposited onto the forming surface in distinct layers, the wet web including at least a first layer and a second layer, the conductive fibers all being contained in the second layer.
4. A process as defined in claim 1 , wherein the wet web is combined with a second wet web prior to being dried.
5. A process for producing a conductive paper web comprising:
depositing an aqueous suspension of fibers onto a porous forming surface to form a wet web, the aqueous suspension of fibers comprising pulp fibers and conductive fibers, the conductive fibers comprising carbon fibers, the carbon fibers being present in the wet web in an amount of at least about 2% by weight based upon the total fiber weight;
pressing the wet web against a plurality of heated cylinders to dry and densify the web, the resulting dried web having a bulk of less than about 2 cc/g; and
wherein the forming surface includes areas having substantially no porosity, the formed wet web including non-conductive zones corresponding to where the areas are located on the forming surface.
6. A process as defined in claim 5 , further comprising the step of coating at least one surface of the web with a binder.
7. A process as defined in claim 5 , wherein the resulting dried web has a tensile strength of at least 1500 grams per inch in the machine direction.