Methods for forming multi-layer substrates including top and bottom surface layers and a melt softened thermoplastic material layer between the exterior surface layers, where the thermoplastic material includes polyethylene or has a tan delta value of 0.2 to 0.4 within the temperature range of 100° F.-350° F. The 3 (or more) layers are assembled, and heated, melt softening the thermoplastic material, causing bonding of the thermoplastic layer to the exterior surface layers. A cleaning composition may be loaded onto the multi-layer substrate, where a fluid pathway through the melted thermoplastic material allows the cleaning composition to travel between the surface layers. Adhesion between the surface layers and the thermoplastic layer is provided by the thermoplastic material itself, which bonds to groups of fibers in the surface layers. The process does not require chemical adhesives, any processing water, drying, or the like, so as to be possible with low capital investment.