Obtaining warp knit fabrics from cotton yarn with warp knitting machines

Abstract

A method for producing a warp knit fabric from cotton yarns includes forming a warp yarn by using 80/2 Ne cotton yarn obtained by twisting 80/1 Ne cotton yarns, forming a pile yarn by twisting a polyvinyl alcohol yarn and a cotton yarn, forming a ground yarn by using twisting double ply twisted cotton yarns, knitting the warp yarn and the pile yarn and the ground yarn in a warp knitting machine, treating the warp knit fabric with an acid at 90 C. for twenty minutes, and removing the polyvinyl alcohol yarn from the treated warp knit fabric such that the warp knit fabric is 100% cotton.

Claims

1. A method for producing a warp knit fabric from cotton yarns, the method comprising: forming a warp yarn of 100% cotton by using a 80/2 Ne cotton yarn which is obtained by twisting two 80/1 Ne cotton yarns; forming a pile yarn by twisting a polyvinyl alcohol yarn and a cotton yarn having a thickness of between 120/1 Ne to 0.5 Ne; forming a ground yarn of 100% cotton by twisting two double ply twisted cotton yarns; knitting the warp yarn and the pile yarn and the ground yarn in a warp knitting machine so as to form a warp knit fabric; treating the warp knit fabric with an acid at 90 C. for twenty minutes; and removing the polyvinyl alcohol yarn from the treated warp knit fabric such that the warp knit fabric is 100% cotton.

2. The method of claim 1, wherein the step of knitting comprises: decreasing a tension between a needle rail and an inlay rail of the warp knitting machine.

3. The method of claim 1, wherein the acid is acetic acid.

4. The method of claim 1, wherein the acid is formic acid.

Description

BRIEF DESCRIPTION OF DRAWINGS

(1) FIG. 1 is a detail view of the warp knit fabric.

(2) FIG. 2 is a detail view of the pile yarn and warp yarn positions in the warp knit fabric.

(3) FIG. 3 is a detail view of the warp yarn and ground yarn positions in the warp knit fabric.

(4) FIG. 4 is a schematic view of the manufacturing principle of the warp knit fabrics (spacer fabric) in double needle railed Raschel machines.

(5) FIG. 5 is a schematic view of the principle of warp knitting.

(6) FIG. 5a is a schematic view of lower tilting movement.

(7) FIG. 5b is a schematic view inward oscillating movement.

(8) FIG. 5c is a schematic view of top tilting movement.

(9) FIG. 5d is a schematic view outward oscillating movement.

(10) FIG. 5e shows movements of the inlay rail where the perforated inlay needle is located.

(11) FIG. 6 illustrates the pile yarn (cotton yarn twisted with PVA yarn).

(12) FIG. 7 illustrates the pile yarn's placement inside the inlay needles.

(13) FIG. 8 illustrates the formation route in the system with pile yarn.

(14) FIG. 9 illustrates the formation route in the system with warp yarn.

(15) FIG. 10 illustrates the formation route in the system with ground yarn.

(16) FIG. 11 is a schematic view of the method for producing a warp knit fabric.

PARTS REFERENCES

(17) 10. Warp knit fabric 11. Warp yarn 12. Pile yarn 13. Ground yarn 14. Inlay rail 15. Inlay needle 16. Needle 17. Needle rail 20. Double needle railed Raschel machine 21. 1st inlay rail 22. 2nd inlay rail 23. 3rd inlay rail 24. 4th inlay rail 25. 1st needle rail 26. 2nd needle rail

DETAILED DESCRIPTION OF THE INVENTION

(18) The method for obtaining warp knit fabric (spacer fabric) (10) from cotton yarns in warp knitting machines is disclosed herein detailed description without limiting the scope of the invention.

(19) The invention relates to a method for obtaining terry or non-terry warp knit fabric (spacer fabric) (10) with or without pile from 100% cotton yarns with increased elasticity and tensile strength due to modified torsion and twisting values, using warp knitting machines, intended to be used in the design of different constructions. A detail view of the warp knit fabric (10) is given in FIG. 1.

(20) In knitting the warp knit fabric, 80/2 Ne combed cotton is the warp yarns (11), 100% cotton by using double ply twisted cotton yarns is the ground yarns (13), and cotton yarn twisting with a polyvinyl alcohol yarn is the pile yarns (12). FIG. 2 shows a detail view of the position of the pile yarn (12) and warp yarn (11) in the warp knit fabric (10). FIG. 3 shows a detail view of the position of the warp yarn (11) and the ground yarn (13) in the warp knit fabric (10).

(21) While obtaining the pile yarn (12), cotton yarn is twisted in opposite direction with PVA (polyvinyl alcohol).

(22) The warp knit fabric (10) of the invention is knitted with raw yarns and white tops dyeing is applied. During the tops dyeing process, before the bleaching process, the fabric is treated with acid at 90 C. for 20 minutes. Thereby the PVA fiber is removed from the raw product. In FIG. 4, a schematic view of the manufacturing principle of the warp knit fabrics (spacer fabric) (10) in double needle railed Raschel machines is given.

(23) The present invention is a method of producing a warp knit fabric of 100% cotton. This method includes the steps of: forming a warp yarn of 100% cotton by using a 80/2 Ne cotton yarn which is obtained by twisting two 80/1 Ne cotton yarns; forming a pile yarn with increased strength by twisting a polyvinyl alcohol yarn and a 100% cotton yarn having a thickness ranging from 120/1 Ne to 0.5 Ne; forming a ground yarn of 100% cotton by using double ply twisted cotton yarns, which is obtained by twisting two double ply twisted cotton yarns; knitting the warp yarn and the pile yarn and the ground yarn in a warp knitting machine to form a warp knit fabric; treating a knitted warp knit fabric with an acid at 90 C. for twenty minutes; and removing a polyvinyl alcohol yarn from the threated warp knit fabric such that the warp knit fabric is formed of 100% cotton.

(24) In an embodiment of the inventive method, the warp knitted fabric is treated with an acid, preferably acetic acid, at 90 C.

(25) Another embodiment of the inventive method, the warp knitted fabric is treated with an acid, preferably formic acid, at 90 C.

(26) A feature of the invention is that acetic acid or formic acid may be used as the acid during removal of the PVA yarn from the obtained fabric.

(27) A feature of the invention is that, during the step of obtaining pile yarn (12), the tension created between the needle rail and the inlay rail is decreased using the elasticity of the PVA thread.

(28) A feature of the invention is that, it is possible to obtain pile and terry warp knit fabrics by adding a pile plate to the warp knitting machine used in the step of knitting the warp knit fabric.

(29) FIG. 4 shows the manufacturing principle of the warp knit fabrics (spacer fabric) in double needle. The 1st inlay rail (21) and 4th inlay rail (24) are used for the production of the outer surfaces of the sandwich textile, and the sandwich textile is knitted according to a desired outer surface pattern. Here, different surface constructions can be obtained with the use of different drawing wheels on each inlay rail. While the 1st inlay rail (21) inlays only in the 1st needle rail (25), the 4th inlay rail inlays only in the 2nd needle rail (26), the 2nd inlay rail (23) and 3rd inlay rail (24) inlays in both needle rails. With the 2nd and 3rd inlay rails (23 & 24) inlaying in both needle rails (25 & 26), the binding threads join the two basic fabric surfaces. A minimum of four inlay rails are used according to the characteristics of the product and the expected demands on the product.

(30) FIG. 5 shows the principle of warp knitting. Usually, the needles (16) used in warp knitting machines are arranged in a straight line on a needle rail (17). Each warp yarn (11) is passed through a perforated inlay needle (15). The perforated inlay needles (15) are also arranged on an investment inlay rail (14). Due to the movement of the comb, the warp yarn (1) are entangled around the needles (16). the movement of the needle rail (17) results in the warp yarns (11) simultaneously forming a loop. Needle rails is called Inlay needle.

(31) FIG. 5a show lower tilting. The comb makes the so-called tilting movement. Because with this tilting, each perforated inlay needle (15) (together with the warp yarn (11)) makes a lateral movement (jump) behind the needle (16) (lower tilting).

(32) FIG. 5b show inward oscillating movement. Perforated comb inlay needles (15) then make an inward oscillating movement between the two needles (16). The movements of the inlay needles (15) are guided by the inlay rail (14).

(33) FIG. 5c and FIG. 5d show the top tilting movement and outward oscillation movement, respectively. With the lateral movement, the warp yarns (11) are laid on the bodies of the needles (16) and the inlay needles passing between two neighboring needles (16) make an outward oscillation movement and the movement sequence is completed.

(34) FIG. 5e show movements of the inlay rail (14) where the perforated inlay needle (15) is located.

(35) With different variations, weft and pile yarns are used together with warp yarns in the same working principle. (FIG. 5, 5a-5b)

(36) Warp yarns (beams), pile yarns (beams) and ground yarns (beams) provide the yarns for the warp knitting process. The yarns are fed into the needles via guide inlay needles (15). Together, the needles (16) are moved upward and downward. The supplied yarns are grasped by the needles (15) at its highest point during this action. The yarns are fed to the needles hooks by the guide needles (15), which swing around the needle (16).

(37) FIG. 6 shows the pile yarn (12) with increased strength. As can be seen, the pile yarn is formed by twisted a polyvinyl alcohol yarn and a cotton yarn having a thickness ranging from 120/1 Ne to 0.5 Ne.

(38) FIG. 7 and FIG. 8 shows Pile yarn (12) is placement inside the inlay needles. FIG. 8 shows the pile yarn (12), and the formation route in the system. The pile yarn (12) is formed by twisting a cotton yarn and the PVA yarn.

(39) FIG. 9 shows the warp yarn (11), and the formation route in the system with the start of the warp yarn (11). As can be seen, warp yarn (11) is formed by twisting a first 80/1 Ne cotton yarn and a second 80/1 Ne cotton yarn. More than two first 80/1 Ne cotton yarns may be used to form the warp yarn (11).

(40) FIG. 10 shows the ground yarn (13) in the process to produce the final product. The ground yarn (13) is formed of 100% cotton by using double ply twisted cotton yarns, which is obtained by twisting two double ply twisted cotton yarns.

(41) FIG. 11 shows the WB (warp yarn 11) passing through the inlay needle is guided by the inlay rail bar movements. GB (ground yarn 13) passing through the inlay needle is guided by the inlay rail bar movements. PB 1 and PB 2 refer to pile yarn (12) through the inlay needle is guided by the inlay rail bars movements. GB and WB form the ground fabric and PB1 and PB2 also form the front and back piles.