Introduction of Textile design

Identification of warp and weft

• The selvedge always runs in the lengthwise (warp) direction of all fabrics.
• Most fabrics have lower elongation in warp direction.
• The warp yarns lie straighter and are more parallel in the fabric because of loom tension.
• Fancy or special function yarns are usually in the filling direction.

• Warp yarns tends to be smaller, are more uniform in structure and appearance and have higher twist,
• Fabric crimp is usually greater for weft yarns.
• Fabric characteristics may differentiate between the warp and weft directions. For example: denim has a warp face and satin has warp floats and poplin has a weft rib.

Contact fields

• These are the contact points between warp and weft crossing at right angle.
• The number of contact field always equals the product of the number of warp and weft threads.
• Contact field= RNwa x RNwe

Interlacing field

• These are the points where a yarn of one system of threads (warp) changes its position in relation to other system.
• Types:
• single interlacing field
• Double interlacing field

Formula number

• It is a kind of short hand expression of the waving of warp and weft yarn.
• It gives the information of successive floats.
• The warp floats coming up are put above the fraction line and the weft floats are put under the fraction line.

Repeat number

• It indicates the number of warp and weft yarns in the repeat.
• The repeat number for the warp equals the sum of the figures in the formula number. And for the weft vice versa.
• For example 1/1 plain weave repeat: 2x2

Interlacing ratio

• The interlacing ratio of a fabric is the ratio between the actual number of interlacing field and the maximum number of interlacing fields.
• The degree of interlacing is the interlacing ratio expressed in percentage.