Patent Application
20070122593
This invention relates to wallboard tape. More particularly the present invention relates to wallboard tape wallboard compound adherence beads.
Paper wallboard tape tends to absorb water and soften when applied over thick amounts of compound as is necessary when taping irregular joints and corners. When the paper tape softens, it sags and deforms and a straight line corner is not achieved. Thus, paper tape must be applied over thin layers of compound which requires a number of coats of compound or the imperfections must be pre-filled, increasing labor costs and time to finish. Paper tape does, however, provide good adherence to the compound and provides a good paint surface.
Wallboard tape made from polyvinyl chloride (“PVC”) is known. While PVC tape provides very straight and durable corner beads and seam joints for wallboard installations, the challenge with PVC is to get a strong adherence of the wallboard compound to the PVC tape.
One such product, by the inventor of the present invention, is shown in U.S. Pat. No. 5,418,027, issued to John S. Conboy (the '027 patent), the contents of which are incorporated herein by reference. In the '027 patent, a plastic wallboard tape has a raised center section and outwardly extending wing areas having a coating of fibers adhered to both sides. The raised center of the tape is weakened at the top to cause the tape to crease in a straight line when it is folded at an inside or outside corner to define a straight edge at the corner joint. The combination of the rigid water impervious tape and the fibers allows the tape to be applied over imperfectly fitted wallboard joints with large imperfections because the fibers will achieve a mechanical bond with the wallboard compound or other joint materials, allowing a slow cure, and the tape will not be softened by the compound.
While the invention of the '027 patent greatly improves the adherence of wallboard compound to PVC tape, there is still a need to achieve better adherence of the compound to PVC tape and better acceptance of paint. The present invention achieves this goal.
A wallboard tape comprising a paper tape having two outer parallel edges. At least one pair of raised beads are adhered to the tape and extend generally parallel to the outer edges of the tape. The beads may optionally be formed on the tape from a hot melt adhesive and optionally have a generally arcuate top surface. At least one polyvinyl chloride stiffening strip may optionally be adhered to the tape with a hot melt adhesive and a protuberance on the side of the tape opposite the beads and running the length of the tape near the center of the tape also may optionally be applied.
In the accompanying drawings which form part of the specification and wherein like numbers and letters refer to like parts wherever they occur
While this invention is susceptible of embodiment in many different forms, there is shown in the drawings and will herein be described in detail preferred embodiments of the invention with the understanding that the present disclosure is to be considered as an exemplification of the principles of the invention and is not intended to limit the broad aspect of the invention to the embodiments illustrated. The scope of the present invention is intended to be limited only by the explicit terms of the claims.
The present invention comprises an improvement in composite paper-based wallboard tape. Specifically, in the preferred embodiment of the invention, the tape comprises one or more raised beads adhered to the tape and, preferably, run adjacent the outer edges of the tape to improve tape adherence to the wallboard compound. The tape may further include one or more PVC strips that are preferably located along the length of the tape and between the raised beads. The beads may be continuous or interrupted.
In that regard and referring to
The tape 10 is preferably about 2 inches wide and about 0.009 inches thick and the stiffening strips 18 are preferable about 0.719 inches wide each and about 0.016 inches thick and separated by about 0.063 inches. Moreover, the raised beads are preferably about 0.015 in height above the skim coat of adhesive which is about 0.002 in thickness. The raised beads 16 generally form an arcuate top surface 20.
Referring to another embodiment of the present invention in
The tape 100, in one embodiment, is preferably about 3 inches wide and about 0.009 inches thick, and the stiffening strips 18 are preferable about 1.063 inches wide and about 0.025 inches thick each and separated by about 0.125 inches. The raised beads 106 are preferably about 0.015 inches in height above the skim coat or tapered coat of adhesive, which is about 0.002 inches in thickness, and the beads are about 0.030 inches wide. Moreover, the raised beads 108 are preferably about 0.020 inches in height above the skim coat or tapered coat of adhesive and about 0.040 inches wide. The raised beads 106 and 108 generally form arcuate top surfaces 116 and 118. The protuberance 114 is preferably about 0.125 inches wide and about 0.006 inches tall and has a top surface 122 that forms an arcuate surface. The arcuate surface preferably has a radius of about 0.329 inches.
The tape 100, in another embodiment, is preferably about 4.125 inches wide and about 0.009 inches thick, and the stiffening strips 18 are preferable about 1.500 inches wide and about 0.030 inches thick each and separated by about 0.125 inches. The raised beads 106 are preferably about 0.015 inches in height above the skim coat or tapered coat of adhesive, which is about 0.002 inches in thickness, and the beads 106 are about 0.030 inches in width. Moreover, the raised beads 108 are preferably about 0.024 inches in height above the skim coat or tapered coat of adhesive and about 0.048 inches in width. The raised beads 106 and 108 generally form arcuate top surfaces 116 and 118. The protuberance 114 is preferably about 0.125 inches wide and about 0.006 inches tall and has a top surface 122 that forms an arcuate surface. The arcuate surface preferably has an about 0.329 inch radius.
Referring to
Referring to
While the specific embodiments have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying claims.
