| 摘要 |
<p>A nonwoven polyolefin sheet useful as a primary carpet backing in making a moldable, tufted automotive carpet. The polyolefin sheet, preferably polypropylene, is prepared by melt spinning filaments from a plurality of spinnerets and then drawing the spun filaments to a draw ratio of less than 2.0 to maintain high filament elongation as the filaments move from high to low elongation as the draw increases. The drawn filaments are deposited in both the machine and cross-machine directions on a moving collection belt to form a nonwoven sheet having a unit weight of 100 to 150 g/m2. The resulting sheet is lightly bonded using a steam bonder and then debonded such that sheet thickness increases by between 2.5 and 3.5 times. The tufted sheet has an elongation of at least 40 %. The invention sacrifices high sheet strength for tufted sheet elongation in both the machine and cross-machine directions in order to make a moldable, tufted automotive carpet that resists tearing, creasing and grinning while still retaining its shape after demolding.</p> |
