Patent Application
20100285259
This invention relates to an improved reinforced, self-adhering, construction tape. More particularly, this invention relates to a novel, construction tape that has application in the construction industry such as for balcony flashing tape, flashing for roofing joints, foundation flashing, step flashing under siding, balcony and breezeway flashing, and the like.
In the building construction industry, such as for example residential homes, maintaining water proof integrity of the structure at junction locations is essential. In this a construction junction naturally exists around balcony additions, foundation transitions, chimney and skylight junctions, roof transitions, and the like. Each of these junction areas must be water proof and free from flowing and capillary water invasion from external sources.
In the past junction or transition locations have been covered with metal flashing and sealed around the edges by elastomeric calking. Alternatively, or in addition, transition junctions have been sealed by application of a liquid sealant which can be rolled or sprayed over a joint and allowed to set into a firm water resistant film.
Another system employed in the past involves the application of successive layers of felt paper and application of hot bitumen composition that is used to coat and seals joints.
In still a further previously know system a spun bonded polyester strip was provided with longitudinal reinforcing and self adhering adhesive which has been applied in widths of four to as much as eight or more inches over joints, cracks and flashing junctions to maintain water integrity of a construction structure. Although such tapes exhibit enhanced utility it has been determined that further improvement is possible with respect to edge sealing integrity and reinforcing width as well as specific component details of an overall enhanced construction tape. In this a degree of edge or border flexibility for permitting some structural creep or movement without interfering with a watertight edge seal while maintaining a central core strength of the tape would be highly desirable. Moreover enhanced component detail has been envisioned for specific operative combinations of components.
Although previously known systems are operative they exhibit limitations such as difficulty of application and reliability of performance. Moreover cracking and structural shifting of building joints renders some prior systems inoperative and in need of maintenance and/or replacement repair.
In view of the above and other limitations, a need exists for sealing junction transitions of building joints that is easy to install and reliable in performance over an extended period of time.
The problems suggested in the preceding are not intended to be exhaustive but rather are among many which may tend to reduce the effectiveness of prior water barrier systems for building junctions Other noteworthy problems may also exist; however, those presented above should be sufficient to demonstrate that waterproofing construction junctions appearing in the past will admit to worthwhile improvement.
One embodiment of the invention comprises a laminated construction tape for use as balcony flashing tape, flashing for roofing joints, foundation flashing, step flashing under siding, and the like. The laminated construction tape includes a flexible, spun bonded polyester strip and a first layer of adhesive longitudinally extending along and covering a central strip of the spun bonded strip. A layer of reinforcing polyester yarns is bonded to the spun boned strip by the first layer of adhesive. A second of adhesive is applied to the spun bonded strip and is coextensive with the strip and covers the layer of reinforcing as well as the lateral edges of the spun bonded strip on each side of the band of polyester yarns. In order to provide enhanced adhesion in combination with core strength it has been determined that the sum of the width of lateral edges running along the spun bonded strip is greater than twenty five percent (25%) and less than fifty percent (50%) of the width of the spun bonded strip. A release strip is applied over the second layer of adhesive and is removable for application of the laminated construction tape to a building junction site.
Other aspects of the present invention will become apparent from the following detailed description of embodiments taken in conjunction with the accompanying drawings wherein:
Turning now to the drawing where like numerals indicate like parts,
Turning now to
Still another illustrative example of use of the subject laminated construction tape is shown in
Turning specifically now to
The spun bonded polyester strip 150 has a first side 152 and a second side 154, a first edge 156 and a second edge 158. The thickness “A” of the spun bonded strip for most construction projects is approximately between 9.2 millimeters and 11.6 millimeters with a preferred thickness of approximately 10.4 millimeters. The spun bonded polyester strip as a preferred range of unit weight of approximately between 1.3 and 1.4 ounces per square yard and a preferred weight of approximately 1.35 ounces per square yard. In a preferred form the subject spun bonded material exhibits a sheet trapezoid tear strength of approximately 7.0 pounds.
A first layer of adhesive 160 is applied to the second side 154 of the spun bonded strip 150 along a central core region of the strip without extending to the edges 156 and 158 of the strip 150. In a preferred form the first layer of adhesive 160 is composed of water based ethylene vinyl acetate adhesive.
The equal lateral margins “B” and “C” that extend along the strip 150 can vary in width but in a preferred form comprise, in sum, between approximately twenty five percent (25%) and fifty percent (50%) of the width of the entire strip 150 with a preferred dimensional ratio being approximately thirty percent (30%). The total width of the laminated construction tape 130 can vary in accordance with the intended construction applications but the width is preferably four inches, six inches or eight inches in most applications but can be greater than a foot in some instances. In the preferred applications, however, the sum of the margins “B” and “C” in the most preferred form is approximately one point two inches for a four inch tape, one point eight and two point four inches respectively.
A central core layer “D” of reinforcing 164 comprising a band of substantially parallel polyester yarns 166 extend coextensively with the first layer of adhesive 160 along the center of the spun bonded polyester strip 150. In a preferred embodiment the substantially parallel polyester yarns have a denier of approximately 1513 grams per nine kilometers. The reinforcing provides structural integrity to the center region of the strip 150 and is held in position by the first layer of adhesive 160.
A second layer of pressure sensitive adhesive 170 overlays the margins “B”, and “C” of the spun bonded polyester strip 150 and across the core layer “D” of reinforcing polyester yarns 166. The pressure sensitive adhesive (PSA) is composed of an acrylic pressure sensitive transfer adhesive having a high shear strength (dynamic shear of 14.7 psi to 17.4 psi) and a low glass transition (tacky to solid) temperature “Tg” of approximately minus 30 degrees centigrade so that the laminated construction tape can be used in cold weather applications. One PSA that applicant has found suitable is VT 3600 or 3604 manufactured by the Venture Tape Corp. of Rockland, Mass. 02370.
As best seen in
Finally the laminated construction tape 130 is provided with an outer release strip 172 that over lays the second layer of self adhering construction adhesive 170. The release strip is composed of a high density polyethylene coated with a silicone release coating on the side adjacent to the second layer of adhesive 170. In this form the laminated construction tape 130 is suitable to be manufactured and stored on a spool 174 for storage and delivery to a job site.
The release strip includes in one embodiment an x-y pre-marked grid 176 to facilitate cutting and accurate application to a construction joint. In addition the release strip is selected to by easily marked with a conventional ball point pen or carpenter's pencil to facilitate cutting and shaping to fit construction junctions.
A method of application of the laminated construction tape of the subject invention includes unrolling a length of the tape to fit the particular construction purpose. Exact lengths can be measured and marked on either side of the tape. The tape 130 is then cut to length as measured and the release layer at one end is peeled away to permit initial application. As the laminated construction tape 130 is aligned and positioned for application the release layer can be pulled away permitting the second adhesive layer 170 to directly and firmly self adhere to the underlying construction junction. The relatively thicker edge margin areas “B” and “C” (approximately twice the thickness of a central region of the tape) provide secure adhesive contact with an underlying construction component which permits a degree of water tight sealed lateral and/or longitudinal movement while the central portion of the tape 130 provides dimensional stability for the flashing project.
In the preceding specification use of the terms first and second are expressions of differentiation and while first has been used with respect to a side surface of the laminated construction tape 130 there is no structural significance intended by this designation. In addition preferred thicknesses and weight of components have been express as approximately. In this, although the ranges and specific values are preferred it is intended that the scope of the disclosure and claims are not to be limited to exactly the stated ranges and values but would also include equivalent values for the recited functions.
The preceding description has been presented only to illustrate and describe the invention and some examples of its implementation. It is not intended to be exhaustive or to limit the invention to any precise form disclosed. Many modifications and variations are possible and would be envisioned by one of ordinary skill in the art in light of the above teaching.
The various aspects were chosen and described in order to best explain principles of the invention and its practical applications. The preceding description is intended to enable others skilled in the art to best utilize the invention in various embodiments and aspects and with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the following claims; however, it is not intended that any order be presumed by the sequence of steps recited in the method claims unless a specific order is directly recited.
