Knitted Fabric Structure
Knitting is the second largest and most growing technique of fabric manufacturing. Knitted fabrics, known for their elasticity, comfort, and versatility, are integral to various industries, from fashion to technical textiles. A fabric structure constructed through the process of inter-locking loops. Knit fabrics consist of a series of stitches that are formed by needles. These stitches are produced by one or more interlocking loops of yarn ends or equivalent material. The direction in which the loops are formed determines the knit structure. Classification of knitted fabric structure is essential for selecting the right fabric for a particular end-use. The two general classifications of knitted structures are weft knits and warp knits.
In knit fabrics, wales and courses are comparable to the warp and filling in woven fabrics. Wales are the vertical columns of stitches or loops in the lengthwise direction of the fabric. Courses are the horizontal rows of stitches or loops in the crosswise direction of the fabric. Gauge, also spelled gage, indicates the number of wales per inch in a knitted fabric, fineness of the knit, the number of needles per inch used in a machine to create a knit fabric, and size of the stitch.
Variations in the pattern of knits are achieved by changing the arrangement of the basic stitch or loop. The basic nature of the structure of knits offers stretchability not found in woven goods. The ability of a knit to stretch varies according to the direction and complexity of the formation of the loops, the size of the stitch (gauge), and the weight of the yarn (denier). Knits can be manufactured to stretch in either the course or wale direction, or both, depending on the elasticity desired.
Knitting machines produce either tubular or flat goods in a variety of widths depending on the type of machine and the specifications of manufacturers. Tubular and flat goods are used for cut and sew production of knit garments. Flat-bed knitting machines can produce full-fashioned or knit-and-wear garments knitted to fit the shape of the body through the addition or subtraction of stitches during the knitting process. Preshaped, two-dimensional knitted pieces of a garment are produced by the knitting machine and emerge ready to be stitched together. Linking or looping is the process of joining knit trims to the garment by means of an elastic chain stitch seam. The machine opera-tor must match each stitch along the garment panel with each stitch along the edge of the trim piece before they can be joined together.
Knit and wear garments can also be produced on some flatbed knitting machines. Similar to full-fashioned, knit and wear produces preshaped three-dimensional knitted garments to fit the shape of the body but do not require additional stitching for assembly, therefore eliminating preproduction and assembly operations such as cutting, sewing, and linking. These garments emerge ready to wear.
Four stitches can be used in all knitted fabrics:
- Knit or plain stitch
- Missed stitch
- Purl or reverse knit stitch
- Tuck stitch
Weft Knit
Identified by one continuous yarn forming courses across the fabric. A single yarn passes horizontally to all needles to construct loops in a course or row. Each new course is added to the last row of stitches. These knits are character-ized by their moderate to high amount of stretch in the course (crosswise) direction. The amount of stretch provided in the wale (lengthwise) direction varies. These knits are prone to run but only from the last knitted yarn end or if the yarn is cut.
All weft knitted structures are classified into four basic groups according to the arrangement of loops in their courses and wales. Four primary structures plain, rib, purl and interlock are the base structures from which all weft knitted fabrics are derived.
Weft knit structures include:
- Balbriggan
- Bourrelet
- Cable knit
- Double knit
- Faux fur
- Fleece (weft insertion jersey)
- French terry (weft insertion jersey)
- Interlock
- Jacquard jersey
- Jersey knit
- Knit terry
- Lacoste
- Lisle
- Matte jersey
- Pile jersey
- Piqué
- Pont di Rome
- Purl knit
- Rib knit
- Stockinet or stockinette
- Velour
Weft Insertion Jersey
A fabric in which a crosswise yarn is inserted into the loops of the courses as they are knitted. The inserted yarn provides stabilization in the crosswise direction and may also give strength, decoration, and nap to the finished fabric.
Weft insertion knits include:
- Fleece
- French terry
Warp Knit
Identified by a series of yarns forming wales in the lengthwise direction of the fabric. Each course stitch is formed by different types of yarn. Courses are joined together by the adjacent course or row. These knits are characterized by their lack of stretch in the lengthwise direction. The amount of stretch provided in the crosswise direction varies. Warp knits will not ravel or run.
Warp knit structures include:
- Bobbinet
- Crochet
- Filet
- Gossamer
- Illusion
- Intarsia
- Lace
- Mesh (knitted)
- Milanese
- Point d’esprit
- Pointelle
- Polar fleece
- Power net
- Raschel knit
- Simplex
- Thermal knit
- Tricot knit
- Tulle
Warp Insertion
A yarn is inserted vertically, and the loops of the wales are formed around the insertion as they are knitted. The inserted yarn provides stabilization in the lengthwise direction and may provide strength and deco-ration to the finished fabric.
Warp insertion knits include:
- Mali
- Malimo
Conclusion
The classification of knitted fabric into weft and warp structures provides a framework for understanding their diverse applications. Understanding of knitted fabric structure is crucial for textile designers, manufacturers, and consumers in selecting the right fabric for specific functional and aesthetic requirements.
References
[1] Bubonia, J. E. (2017). Apparel production terms and processes. https://doi.org/10.5040/9781501315602
[2] Jamshaid, H., & Mishra, R. (2024). Knitting science, technology, process and materials: A Sustainable Approach. Springer.
[3] Nawab, Y., Hamdani, S. T. A., & Shaker, K. (2017). Structural textile design: Interlacing and Interlooping. CRC Press.
[4] Ray, S. C. (2012). Fundamentals and advances in knitting technology. In Woodhead Publishing Limited eBooks. https://doi.org/10.1533/9780857095558
[5] Thangamani, K., & Sundaresan, S. (2022). Fabric Manufacturing Technology: Weaving and Knitting. CRC Press.
[6] Belal, S. A. (2018). Understanding textile for a merchandiser. http://182.160.97.198:8080/xmlui/handle/123456789/1184
