Patent ID: 9103057
Filing Date: 2015-08-11
Classification: A61F,B32B,D04H,D06C,Y10T

Abstract:
1. A method for making a nonwoven fabric material, the method comprising: a) depositing on a support at least one layer of a biodegradable material comprising long fibers or continuous filaments; b) hydroentangling the at least one layer and drying the hydroentangled material; c) calendering the dried material of step b) to create on the material a calendered pattern which provides a balanced ratio of MD/CD average tensile strength to the nonwoven fabric material, in a range between about 1:1 and about 4:1, wherein the calendering step is performed with a calender comprising ribs evenly alternating with grooves that define a calendering pattern thereon, wherein the calendering pattern of the calender comprises a plurality of ribs that are arranged in rows along the machine direction, each row forming first modules and second modules in alternate alignment, in each of the first modules the ribs being inclined with the same orientation, each first module being adjacent to two second modules having ribs being inclined with an opposite orientation, so that diagonal lines are defined joining corresponding points of the ribs in first modules or second modules, which diagonal lines define the inclined orientation of the ribs in such first modules or second modules, respectively, and wherein a first angle a is formed between the diagonal line defining the inclined orientation of the ribs in the first modules and the cross-direction, the first angle a being less than about 45 ° and a second angle is formed between the diagonal line defining the inclined orientation of the ribs in the second modules and the cross-direction, this second angle being supplementary to the first angle.