This invention relates to wallboard tape. More particularly the present invention relates to wallboard tape including two strips of tape overlaying a portion of one surface of a base tape and separated by a gap.
Paper wallboard tape tends to absorb water and soften when applied over normal amounts of compound as is necessary when taping joints and corners. When the paper tape dries, 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 but must be coated with a thin layer of compound or paint can and will release from the paper surface by blistering or bubbling and sandpaper finishing will scuff the paper if it is not coated with compound.
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, PVC is an expensive wallboard tape component which is not justified in every installation. However, paper-based wallboard tape is insufficient for many installations, particularly for use on exterior or interior corners. The present invention represents an improvement in paper wallboard tape, particularly for interior or exterior corners.
The present invention comprises a wallboard tape having a base layer of paper tape having two parallel outer edges and two strips of paper tape bonded to and overlaying a portion of and applied to one surface of the base layer, said strips of paper tape being parallel to the outer edges and separated by a gap.
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 a base tape layer and one or more paper strips that are bonded to and overlay at least a portion of the base tape and are preferably located along the length of the tape. The paper strips can be provided in one or more layers.
In that regard and referring to
The nodules may be in a strip offset from the edge of the tape but preferably extend to and include the edge of the tape. By having the nodules at the edges as well, this creates a discontinuous edge to the tape which prevents or reduces paper cuts to the installer.
Applied to a top surface 14 of the tape is a protective layer 15 comprising a scuff resistant-water-based styrene acrylic material. The thickness of the protective layer 15 is preferably only a few thousandths thick. This material protects the tape 10 from sanding during installation and also forms a layer that can accept paint.
Applied to and overlaying the length of the bottom surface 12 of the tape 10 are two paper strips 18. The strips 18 are preferably adhered with an adhesive comprising a hot melt, a urethane or a polyamid material.
The strips 18 are preferably spaced apart to define a gap 22 therebetween and are offset from the raised nodules 11 of the base layer 10. Most preferably, the gap aligns with the longitudinal centerline of the tape and provides a relatively flexible hinge so that the tape may be bent or folded along the gap so as to be able to apply the tape to corners and angles. Preferably the strips 18 cover no more than 75% of the base layer and no less than 50% of the base layer and most preferably cover about 66% of the base layer 10. Applied to the top surface 14 of the tape 10 is a thin protective strip 23, preferably a hot melt urethane material (shown in exaggerated thickness in
The strips 18 are preferably made from paper based wallboard tape, although other paper or cellulosic based materials could be used. The strips 18 provide additional rigidity to the paper tape as well as enhanced resistance to water deformation so as to provide a flat, straight seam whether the tape is covering a flat seam of two adjacent pieces of wallboard (a “butt joint”) or is folded to form an inside or outside corner bead to cover the seam where two pieces of wallboard meet at an angle.
The tape 10 is typically from about 2 to about 4, preferably from about 2.0 to about 3.5, most preferably about 3, inches wide and about 0.008-0.010 inches thick. The paper strips 18 are preferable about 0.500 to 1.000 inches wide each and about 0.008 to 0.020 inches thick and separated the gap 22 which is about 0.010 to 0.060 inches wide, most preferably about 0.060 inches wide.
In a second embodiment and referring to
In yet another embodiment of
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.
Number | Date | Country | |
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Parent | 11271623 | Nov 2005 | US |
Child | 12844009 | US |