Secondary wall, immature

Figure 5.36 shows intermediary secondary wall development (immature fibers) in cross section, while Figure 5.37 illustrates cross sections of mature fibers. 

These sections were harvested live and processed in the wet state so they are more rounded, and have not assumed the characteristic Kidney-bean-shaped fiber cross-sectional shape of the dried fiber. Fibers with thinner secondary walls are known as immature, while those with walls at or approaching their maximum thickness are called mature. Thus, maturity is a relative term that is difficult to measure objectively (see Section 7.1). Secondary wall thickness is directly... 

When a cotton boll opens, the fibres are cut off from the transpiration system of the plant. The fibres then dehydrate and become flattened and twisted. The cross section of the cotton fibre after dehydration is generally kidney-shaped, although the shapes range from near circular in mature fibres to flat in immature fibres. The kidney shape is an inherent phenomenon due to zones of different density in the secondary wall layers. ... 

Maturity of cotton fiber is one of the most important properties that influences the aesthetic value of the cotton fabrics. Immature fibers cause undesirable uneven dyeing and white specks such as those defects in dyed goods. A brief introduction to the cotton fiber morphology may be helpful to better understand the term maturity. A schematic description of the cotton fiber structure is depicted in Fig. 2 (1). The fiber can be described in four parts a cuticle, a primary wall, a secondary wall, and the lumen. A cuticle is the wavy layer surrounding the fiber. Beneath the cuticle is the primary wall, which is at least 50% cellulose in the form of microfibrils. The second-... 

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