Nonwoven from bulked filament tow

1. A method of making a nonwoven material having a plurality of randomly oriented and bulked crimped filaments and a plurality of point bonds interconnecting said crimped filaments into a fixed, 3-dimensional structure, comprising the steps of:

bulking the filament tow;

fixing the filaments into the 3-dimensional structure, and

calendering the 3-dimensional structure by overfeeding the bulked filament tow into a calendar to form a nonwoven material having a surface portion of the fixed, 3-dimensional structure having a greater density than an inner portion of the 3-dimensional structure,

wherein the ratio of surface portion density to inner portion density is from 10-110:1.

2. The method of claim 1 , wherein the surface portion density is in the range of 0.300-1.000 g/cm 3 .

3. The method of claim 1 , wherein the inner portion density is in the range of 0.002-0.035 g/cm 3 .

4. The method of claim 1 , wherein the calender is a heated calendar.

5. The method of claim 4 , wherein the heated calender has a temperature in the range of 300-400° F. (148.8-204.4° C.).

6. The method of claim 1 , wherein the calender comprises two rollers heated rollers.

7. The method of claim 1 , wherein the calender comprises two rollers and wherein one of the rollers is heated.

8. The method of claim 1 , wherein the method further comprises injecting steam into the filament tow after bulking.

9. The method of claim 1 , wherein an overfeeding ratio of a linear speed of the tow entering bulking to a linear speed of the tow through the calender is at least 1.5:1.

10. The method of claim 9 , wherein the overfeeding ratio is from 1.5:1 to 16:1.

11. The method of claim 1 , wherein the calendar has a nip gap in the range of 0-10 mm.