Composite floor underlayment with thermoplastic coatings

摘要

Disclosed is a flooring system consisting of a slab (or base) floor, a floor covering, and a composite underlayment extending between the slab floor and floor covering. The composite underlayment may include, for example, one or more set gypsum layers with embedded fibrous mats. An exterior plastic coating is mechanically adhered to an underlying set gypsum layer. The plastic coating chemically bonds and cross-links with polymer additives within the set gypsum core. The result is an underlayment that is a fully integrated polymer matrix with greatly improved durability and surface strength with only minimal increases in cost or weight.

主权项

1. A flooring system (20) comprising:
a slab (22); a laminate floor covering (24) overlying the slab (22), the laminate floor covering (24) constituting a walking surface; an underlayment (28) extending between the slab (22) and the laminate floor covering (24), the underlayment comprising: a set gypsum core (32) with a polymeric additive, the set gypsum core having an upper surface (34) and a lower surface (36), the lower surface (36) contacting the slab (22); a mat (38) secured to the upper surface (34) of the set gypsum core (32), the mat (38) formed from non-woven, randomly aligned glass fibers held together by a binder, the mat (38) being porous and having interior and exterior surfaces; a thermoplastic pre-coating applied to the randomly aligned glass fibers of the mat (38); a dense gypsum layer (42) formed at the upper surface (34) of the set gypsum core (32), the dense gypsum layer (42) coating and penetrating the mat, whereby the exterior surface of the mat is substantially covered by the dense gypsum layer to form a boundary layer (44), the dense gypsum layer (42) including a polymeric additive; a coating (46) the majority of which comprises a non-curing hot melt thermoplastic with a melting point between 100° to 500° F., the coating mechanically adhered to the boundary layer (44) and having a thickness of between 0.01 to 500 mils; an adhesive layer (26) securing the laminate floor covering (24) to the coating (46); the coating (46) being chemically bonded to and cross-linked with the thermoplastic pre-coating and the polymeric additives in the set gypsum core (32), the boundary layer (44), and dense gypsum layer (42) to form a composite polymer matrix.