Right Pointe’s NoBox Crack Sealant is now a Patent!
Patent Number: US20140033650A1
Sealants are used for the sealing of joints and cracks in concrete and asphaltic pavements and parking lots. It is known in the art to deliver packaged blocks of sealant material to a job site, which are then melted in a kettle on-site. The liquefied melted sealant is then used to seal joints and/or fill cracks in the pavement. It is also known in the art to use a material for the packaging that itself is an ingredient for including into the sealant product. Prior art which describes such a system is U.S. Pat. No. 8,017,681 to Guymon et al., which discloses adding a thermoplastic product to a foamed polymer container, the foamed polymer container being an ingredient in the sealant product such that the entire container and its contents can be placed in a kettle on the job site and melted. However, foamed polymer containers are expensive, and must be separately transported and stored in preparation for the sealant packaging process. Moreover, the foamed polymer container causes problems as it melts with the sealant in the kettle on-site. Also known is the use of less bulky polypropylene film as packaging, as described in U.S. Pat. No. 5,452,800 to Muir for use with roofing asphalt applications. In Muir, a mold with dimensions to produce a 50-pound asphalt block is lined with polypropylene film, liquid asphalt is poured into the lined mold, and the mold is cooled. When the asphalt is cooled to solid, the asphalt covered by the polypropylene film is removed, the film forming the packaging for the asphalt block which then melts with the asphalt is heated in the on-site vat. A portion of the top of each asphalt block is left uncovered by the film, such that when packages are stacked the top asphalt surface of a package will adhere to the bottom of an adjacent package. However, Muir does not disclose use of such a packaging method for joint sealant material. Moreover, Muir discloses forming a single, large block of asphalt material for melting on-site, which results in a slow melting time due to the required heating for a large solid block of material.
The present invention solves the existing limitations. The present invention relates to an improved sealant packaging and method for use with the sealing of joints and cracks in concrete and asphaltic pavements and parking lots. In particular, the present invention provides a method of forming a package of two or more blocks of sealant, wherein multiple blocks of sealant are contained by a sheet of polypropylene and form a self-sealed package of multiple blocks for melting in a kettle on the job site. The polypropylene sheet acts as an inexpensive, easily stored container for the sealant, and can also be melted into the sealant mix at the job site. In a preferred embodiment, sealant material is liquid at pour temperature and is dispensed by volume into aluminum pans lined with a sheet of polypropylene or similar material. As the sealant fills the pan the sheet repositions itself against all open sides of the pan, with the sealant taking the shape of the pan. The filled pan is then cooled so that sealant becomes a solid block of material, covered on all sides except the top surface of the block by the polypropylene sheet such that the polypropylene sheet forms a container for the sealant. The polypropylene sheet also acts a release liner for easily removing the sealant blocks from the pan. A second block is formed in the same manner, and two or more contained blocks are then stacked together, with the open ends of two blocks placed adjacent to one another, and the open sides of any additional blocks placed on the bottom of the stack of two, forming a self-sealed package of two or more blocks. The package of two or more blocks is then sealed together with a film, such as by shrink-wrapping, and delivered to the job site. When the package is placed in a melting kettle, heat migrates through the spaces between the individual sealant blocks unlike prior systems which use a single, large block sealant material, and allows the smaller sealant blocks to melt more quickly and evenly in the kettle.