Carpets, such as free-lay carpet or backed carpet tile, have been prepared as either a tufted or a fusion-bonded carpet material having a wear face surface.
Tufted carpet tile generally comprises a primary carpet base sheet material having a plurality of tufted yarns through the primary base sheet material to form a wear face surface of loop or cut pile, and usually with a precoat, such as of a latex-type material, like carboxylated styrene-butadiene-styrene precoat, on the back surface to bond the yarn to the primary back. Tufted carpet roll goods usually have a secondary backing of jute, woven polypropylene or foam. Tufted carpet tile includes a backing layer which generally comprises a solid, thermoplastic material, such as atactic polypropylene, bitumen or polyvinyl chloride, preferably with a glass fiber sheet material, such as a mesh or fleece material, embedded therein to impart dimensional stability to the carpet tile. The backing may also include a foam-type backing layer, such as a PVC or urethane foam layer. Non-thermoplastic materials, such as polyurethane, may also be used for the backing. In addition, the tufted carpet tile may include a secondary backing sheet, such as of fiberglass, polypropylene or polyester-type material, or in fact, may be laminated and/or contain a pressure-sensitive, adhesive, strippable layer for application to a substrate.
Fusion-bonded carpet has essentially the same backing except that the fusion-bonded carpet is characterized by a plurality of cut pile yarns, for example, of nylon or other natural or synthetic fibrous-type material, implanted in an adhesive layer, particularly a thermoplastic, like a polyvinyl chloride layer, or a hot-melt adhesive layer. Where a polyvinyl chloride plastisol is used, heating of the layer gels and then fuses the layer into solid form, while with hot-melt adhesive material, a melted layer is applied and subsequently cooled into solid form. The plurality of fibrous yarns are bonded to and extend upright from the adhesive base layer to form a face wear surface. Generally, a fusion-bonded carpet also includes an adjacent backing layer of a glass fiber scrim material having large open areas and a glass fiber fleece which serves as a stabilizing carrier.
Fusion-bonded carpets may be prepared employing a number of well-known, but different techniques and machines in both horizontal and vertical processes known as the I-bond or U-bond processes. The single-end fiber implantation technique, known as the I-bond process, holds the ends of the severed yarns in place by a layer of an adhesive material on a backing material, for example, a fiberglass scrim-type material adjacent to a non-woven, glass fiber fleece layer. Thereafter, the free ends of the fusion-bonded carpet may be embedded in another adhesive layer as before on the same or different backing material, and the resulting sandwich-type carpet then cut, for example, with an oscillating blade in a vertical fusion-bonding method or by a continuing band knife in the horizontal fusion-bonding method, to form two rolls of fusion-bonded carpet having a cut wear face surface for backing into carpet tile or used as roll goods. In another I-bond process, the severed yarn has one end implanted directly into an adhesive layer on a backing sheet, with the other severed end forming the wear face surface of the carpet.
The U-bond process generally includes a corrugated or pleated layer of yarn, wherein each loop end is placed in a layer of adhesive material on backing sheet material, and then the sandwich-formed carpet material cut to form two rolls of fusion-bonded carpet, each roll having cut loops of yarn embedded in the adhesive layer; hence, the name U-bond process.
The fusion-bonded carpet material prepared by these various processes can then be used as free-lay carpet or be converted into carpet or carpet tile with the application of a suitable backing layer and cutting or trimming it into suitable form.
It is desirable to provide for a new and improved fusion-bonded carpet material prepared by a modified I-bond process, including a carpet tile characterized by novel design patterns on the face wear surface and for a method for preparing such carpet material.