| 摘要 |
A method of forming a vacuum bonded non-woven batt includes the steps of blending at least first and second staple polymer fiber constituents. One of the fiber constituents has a relatively low predetermined melting temperature and the other a relatively high melting temperature. The intermixture is formed either into a relatively thick single layer web or a relatively thin web which is then formed into a relatively thick multilayer web structure. The web structure is positioned on a rotating, air permeable drum and a vacuum is used to substantially reduce the thickness and increase the density of the web structure. The web structure is heated to a temperature at or above the relatively low melting temperature of the first fiber constituent and below the melting temperature of the second fiber constituent while under vacuum to release the plastic memory of the fibers of the first fiber constituent in their compressed configuration. The two types of fibers are fused to themselves to form a batt having intimately interconnected and fused first and second fiber constituents. The apparatus on which the above method is performed includes a housing having two perforated counter-rotating drums positioned therein with vacuum means for applying a vacuum through the drum and through the web structure to reduce the thickness and increase the density of the web structure by vacuum pressure alone. Heating means heats the web structure as it is moved through the housing to release the plastic memory of the fibers of the first fiber constituent in their compressed configuration and fuse them to themselves and to the fibers of the second fiber constituent to form a relatively dense batt.
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