Method to make circular-knit elastic fabric comprising spandex and hard yarns
Circular-knit, elastic, single-knit jersey fabric, of spun and/or continuous filament hard yarns with bare spandex plated in every course, has a cover factor in the range of 1.3 to 1.9, a basis weight from 140 to 240 g/m 2 , an elongation of 60% or more and low shrinkage. The circular knit, single-knit jersey fabric is produced by maintaining the draft of the spandex at or below 2× (100% elongation) and maintaining the finishing and drying temperature(s) below the spandex heat set temperature. The knit fabric meets the end-use specifications without heat setting.
1. A method for making a circular knit, single jersey fabric, comprising the steps of:
providing a bare spandex yarn;
providing a hard yarn selected from the group consisting of spun yarns, continuous filament yarns and combinations thereof;
plating the bare spandex yarn with the hard yarn; and
circular knitting the plated bare spandex yarn and hard yarn in every knit course to form a circular knit, single jersey fabric, wherein feed of the bare spandex yarn is controlled so that the bare spandex yarn is drafted no more than about 2× its original length when knit to form the circular knit, single jersey fabric.
2. The method of claim 1 wherein, in the step of providing a bare spandex yarn, the bare spandex yarn is further defined as bare spandex yarn from about 13 to about 33 dtex.
3. The method of claim 1 wherein, in the step of providing a hard yarn, the hard yarn is further defined as a hard yarn having a total yarn count (Nm) from about 35 to about 85.
4. The method of claim 1 wherein, in the step of circular knitting the plated bare spandex yarn and hard yarn in every knit course to form a circular knit, single jersey fabric, the circular knit, single jersey fabric has a cover factor of from about 1.3 to about 1.9.
5. The method of claim 4 wherein the cover factor of the circular knit, single jersey fabric is about 1.4.
6. The method of claim 1 further comprising the step of exposing the circular knit, single jersey fabric to at least one further treatment step, wherein such treatment step occurs at a temperature below a temperature required to heat set the bare spandex yarn.
7. The method of claim 6 wherein the circular knit, single jersey fabric is exposed to a temperature below about 160° C. during the at least one further treatment step.
8. The method of claim 6 , wherein the at least one further treatment step is selected from the group consisting of cleaning, bleaching, dyeing, drying, compacting, and combinations thereof.
9. The method of claim 8 , wherein the at least one further treatment step is selected from the group consisting of drying, compacting, and combinations thereof, and wherein the circular knit, single jersey fabric is subjected to an overfeed in its length during the at least one further treatment step.
10. The method of claim 1 , wherein the circular knit, single jersey fabric has a spandex content of from about 3.5% to about 14% by weight based on the total fabric weight per square meter.
11. The method of claim 10 , wherein the circular knit, single jersey fabric has a spandex content of from about 5% to about 10% by weight based on the total fabric weight per square meter.
12. The method of claim 1 wherein, in the step of providing a hard yarn, the hard yarn is selected from the group consisting of spun cotton, cotton blended with synthetic fiber, cotton blended with yarn, and combinations thereof.
13. The method of claim 1 , wherein the hard yarn is selected from the group consisting of cotton and a cotton blend, and the circular knit, single jersey fabric has a basis weight of from about 140 to about 240 g/m 2 .
14. The method of claim 1 , wherein the circular knit, single jersey fabric has an elongation of at least 60% in a warp direction thereof.
15. The method of claim 1 , wherein the circular knit, single jersey fabric has a shrinkage of about 7% or less after washing.
16. A circular knit, elastic, single jersey fabric made by the method of claim 1 .
17. The circular knit, elastic, single jersey fabric of claim 16 , wherein the hard yarn is cotton or a cotton blend, and the circular knit, elastic, single jersey fabric has a basis weight of from about 140 to about 240 g/m 2 .
18. The circular knit, elastic, single jersey fabric of claim 16 , wherein the circular knit, elastic, single jersey fabric has an elongation of at least 60% in a warp direction thereof.
19. The circular knit, elastic, single jersey fabric of claim 16 , wherein the circular knit, elastic, single jersey fabric has a shrinkage of about 7% or less after washing.
20. A garment made from the circular knit, elastic, single knit jersey fabric of claim 16 .
21. A method for making a circular knit, elastic, single jersey fabric, comprising:
plating a bare spandex yarn with a hard yarn, wherein the bare spandex yarn is from about 17 to about 33 dtex and can be heat set within a heat setting efficiency of at least about 85% at a heat setting temperature, and wherein the hard yarn has a total yarn count (Nm) of about 35 to about 85;
circular knitting the plated bare spandex yarn and hard yarn in every knit course to form a single knit jersey fabric having a cover factor of from about 1.3 to about 1.9;
controlling the feed of the bare spandex yarn so that the bare spandex yarn in the circular knit, elastic, single jersey fabric is drafted no more than about 2× its original length; and
maintaining the circular knit, elastic, single jersey fabric below the heat setting temperature of the bare spandex yarn during further processing.
22. The method of claim 21 , wherein the bare spandex yarn is present in the circular knit, elastic, single jersey fabric in an amount from about 3.5% to about 14% by weight based on the total fabric weight per square meter.
23. The method of claim 22 , wherein the bare spandex yarn is present in the circular knit, elastic, single jersey fabric in an amount from about 5% to about 10% by weight based on the total fabric weight per square meter.
24. The method of claim 21 , wherein the circular knit, elastic, single jersey fabric has a cover factor of about 1.4.
25. The method of claim 21 , further comprising at least one further treatment step selected from the group consisting of drying, compacting, and combinations thereof, and wherein the circular knit, single jersey fabric is subjected to an overfeed in its length during the at least one further treatment step.
26. The method of claim 21 , further comprising the step of exposing the circular knit, single jersey fabric to at least one further treatment step, wherein such treatment step occurs at a temperature below about 160° C.
27. The method of claim 26 , wherein the at least one further treatment step is selected from the group consisting of cleaning, bleaching, dyeing, drying, compacting, and combinations thereof.
28. A circular knit, elastic, single knit jersey fabric made by the method of claim 21 .
29. The circular knit, elastic, single knit jersey fabric of claim 28 , wherein the hard yarn is cotton or a cotton blend, and the circular knit, elastic, single jersey fabric has a basis weight of from about 140 to about 240 g/m 2 .
30. The circular knit, elastic, single knit jersey fabric of claim 28 , wherein the circular knit, elastic, single jersey fabric has an elongation of at least about 60% in a warp direction thereof.
31. The circular knit, elastic, single knit jersey fabric of claim 28 , wherein the circular knit, elastic, single jersey fabric has a shrinkage of about 7% or less after washing.
32. A garment made from the circular knit, elastic, single knit jersey fabric of claim 28 .