Method of making a bonded batt with low fiber leakage

DETAILED DESCRIPTION OF THE INVENTION Thus, the invention provides fiberfill batts, such as are needed for use in premium apparel, by first preparing a homogeneous blend of polyester fiberfill (70-96% by weight of the blend) and a suitable binder fiber (4-30% by weight of the blend).
This blend is converted on a card or garnet to a web which may then be layered or cross lapped to form a batting to whose upper and lower faces is serially applied a suitable latex (e.
g.
, a colloidal dispersion of acrylic polymers and/or copolymers in water, discussed in more detail hereinafter), e.
g.
, by spraying.
The sprayed batting is heated, e.
g.
, conveniently by being passed through a heated oven to dry the coating(s) and to polymerize the polymeric component(s) to high molecular weight, and to activate the binder fiber.
This may be conveniently done in three passes through such an oven, two to serially cure each coating, after such coating is applied to each face, and a third pass to supplement the other two and to activate the binder fiber in preparation for the hot-rolling.
The bonded batt is passed around or through heated rolls (S-wrap or calendering process) to soften and spread the cured resin and ensure its complete and even distribution among the fibers in the two faces (large surfaces) of the batt to prevent fiber leakage through the batt and, if needed, to ensure that the batt is of the desired thickness.
The resins that may be used herein are termed variously, by different manufacturers, as "soft" or "medium", or even "very soft", but are characterized by having second order glass transition temperatures (Tg) of about 0 C or less.
They provide both softness and drapability to the batt when used in, e.
g.
, apparel, while acting as barrier to fiber leakage from the batt.
The final batts may have a basis weight of 1.
5 to 12 oz.
/yd.
sup.
2.
(50 to 400 g.
/m.
.
sup.
2) and a thickness of 0.
07 to 0.
20 inch/oz.
/yd.
.
sup.
2 (0.
05 to 0.
15 mm.
/g.
/m.
sup.
2.
).
Thus the batts of this invention are prepared from a blend of polyester fiberfill and binder fibers, and the fibers in the faces are sealed by a suitably soft-type resin coating