Method to make circular knit elastic fabric comprising spandex and hard yarns
View Patent ↗Circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece are disclosed that include a bare elastomeric material plated with spun and/or continuous filament hard yarns. The circular knit, elastic fabrics of at least one of single jersey, French terry, and fleece are manufactured by a method that does not require a dry heat setting step. The method requires drafting the bare elastomeric material no more than about 7× its original length when knitting to form the circular knit, elastic, single jersey, French terry, or fleece fabric. The method includes contacting the knit fabric with an aqueous solution under very low tension and under conditions of temperature and pressure for a period of time sufficient to substantially set the elastomeric material.
1. A method for making a circular knit, elastic, single jersey fabric, the method comprising the steps of:
providing an elastomeric material;
providing at least one hard yarn selected from the group consisting of spun yarns, continuous filament yarns, and combinations thereof;
plating the elastomeric material with the at least one hard yarn;
circular knitting the plated elastomeric material and at least one hard yarn in every knit course to form a circular knit, elastic, single jersey fabric; and
contacting the circular knit, elastic, single jersey fabric with a continuous phase aqueous solution under conditions of temperature and pressure and for a period of time sufficient to substantially set the elastomeric material.
2. The method of claim 1 wherein, in the step of providing an elastomeric material, the elastomeric material is further defined as bare spandex yarn.
3. The method of claim 1 wherein, in the step of providing an elastomeric material, the elastomeric material is further defined as bare spandex yarn from about 15 to about 156 dtex.
4. The method of claim 1 wherein, in the step of providing at least one hard yarn, the at least one hard yarn is further defined as a hard yarn having a yarn count (Nm) from about 10 to about 165.
5. The method of claim 1 wherein, in the step of circular knitting the plated elastomeric material and at least one hard yarn in every knit course to form a circular knit, elastic, single jersey fabric, the circular knit, elastic, single jersey fabric has a cover factor of from about 1.05 to about 1.9.
6. The method of claim 1 , further comprising the step of exposing the circular knit, elastic, 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 elastomeric material.
7. The method of claim 6 , wherein the circular knit, elastic, 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 any combination 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, elastic, 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, elastic, single jersey fabric has an elastomeric content of from about 3.5% to about 30% by weight based on the total fabric weight per square meter.
11. The method of claim 1 wherein, in the step of providing at least one hard yarn, the at least one hard yarn is selected from the group consisting of synthetic filament, spun staple yarn of natural fibers, natural fibers blended with synthetic fibers or yarns, spun staple yarn of cotton, cotton blended with synthetic fibers or yarns, spun staple polypropylene, polyethylene or polyester blended with polypropylene, polyethylene or polyester fibers or yarns, and combinations thereof.
12. The method of claim 11 wherein the at least one hard yarn is a heat sensitive yarn.
13. The method of claim 1 , wherein the at least one hard yarn is selected from the group consisting of cotton and a cotton blend, and the circular knit, elastic, single jersey fabric has a basis weight of from about 100 to about 500 g/m 2 .
14. The method of claim 1 , wherein the circular knit, elastic, single jersey fabric has an elongation of at least about 60% in a warp direction thereof.
15. The method of claim 1 , wherein the circular knit, elastic, single jersey fabric has a shrinkage of about 14% or less after washing.
16. The method of claim 1 , wherein the circular knit, elastic, single jersey fabric is produced in the form of a tube and has substantially no visible side creases formed therein.
17. The method of claim 1 wherein, in the step of contacting the circular knit, elastic, single jersey fabric with a continuous phase aqueous solution, the temperature is in a range of from about 105° C. to about 145° C.
18. The method of claim 1 wherein, in the step of contacting the circular knit, elastic, single jersey fabric with a continuous phase aqueous solution, the period of time is in a range of from about 5 minutes to about 90 minutes.
19. The method of claim 1 wherein, in the step of circular knitting the plated elastomeric material and at least one hard yarn, the feed of the elastomeric material is controlled so that the elastomeric material is drafted no more than about 7× its original length when knit to form the circular knit, elastic, single jersey fabric.