IMPACT OF DIFFERENT PERCENTAGES OF LYCRA IN THE PLATING YARN, ON PHYSICAL AND DIMENSIONAL PROPERTIES OF THE SOCKS
INTRODUCTION:-
Lycra air coved yarns have an important role in socks manufacturing. These yarns are being used as a plating yarn. Lycra helps in offering wrinkle resistance and garment integrity with comfort. The wearer of lycra containing socks feels less fatigued and muscle strain. Researchers have found that natural fibres like cotton, silk, wool offers comfort and aesthetic properties while synthetic fibres like nylon, polyester, and polyurethane are more known for strength and elasticity; in other words, neither natural nor synthetic fibres can fulfill these needs when used singly in the Fabric. Blending of these natural and synthetic fibres/yarn homogeneously thus becomes essential to take the advantage of better properties. Blending these fibres with spandex/Lycra fulfils majority of the requirements of the consumer and it is found that Lycra is readily compatible with most other fibres, including nylon, polyester, acetate, polypropylene, acrylic, cotton, wool, and rayon. However, the proportion of Lycra in the blends with these fibres varies significantly depending upon the end uses and application of the materials.
It is difficult to control lycra percentage in manufacturing of air covered Yarns; This study aims to investigate the impact of change in lycra percentage on the dimensional properties of socks.
MATERIAL AND METHODS:
The present research work was conducted in QA Lab in collaboration with R&D and Processing departments of Interloop Ltd. The socks were produced by using 20/150 PCVD lycra 4%, 20/150 PCVD lycra 6 % at 20/150 PCVD lycra 6% and then at 20/150 PCVD 4% specs settings respectively. Similarly socks were produced with 20/70/1 NCVD lycra 8 % and 20/70/1 NCVD lycra 12.5 % lycra at NCVD lycra 12.5 % and NCVD lycra 8% specs settings. The greige specs were measured Socks were then processed for washing, bleaching and dyeing. Following recipes were used in processing.
- Simple cold wash at 40°C for 15min
- H2O2 Bleaching
- Reactive dyeing (Black) about 8% shade depth
From Table 2, it is concluded that rib stretch values boosted up for wash, bleach and dye articles till +1.5cm, 0.25cm and +1.0cm correspondingly for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting. Expansion of +1.5cm and +1.0cm is detected in wash and dyed cases for 20/70/1 NCVD Lycra 12.5% at 20 70/1 NCVD Lycra 8% specs setting. Where as, these values shrink to -0.75cm & -1.05cm in bleaching and dyeing respectively by 20/150 PCVD Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting.
Table 3. EFFECT OF LYCRA %AGE ON BODY STRETCH:-
Setting
Elastomaric Yarn
Process
Body Stretch (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+0.5
Bleach
+0.5
Dye
+0.5
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
-1.25
Bleach
-1.0
Dye
-1.0
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+2.0
Dye
+1.5
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
-1.5
Dye
-2.25
Table 3, illustrated that body stretch values of washed, bleached and dyed articles increased till +0.5cm for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting. Extension of +2.0cm and +1.5 is also measured for washed and dyed articles when 20/70/1 NCVD Lycra 12.5% runs at 20 70/1 NCVD Lycra 8% specs setting. While drop off -1.25cm, -1.0cm and -1.0cm is observed for washed, bleached and dyed respectively for 20/150 PCVD Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting. Shrinkage of -1.5cm and -2.25cm is observed for 20/70/1 NCVD Lycra 8% knitting at 20 70/1 NCVD Lycra 12.5% specs setting.
Table 4. EFFECT OF LYCRA %AGE ON RIB LENGTH:-
Setting
Elastomaric Yarn
Process
Rib Length (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+1.0
Bleach
+0.75
Dye
0
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
0
Bleach
-0.5
Dye
-0.25
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+0.5
Dye
+0.25
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
-0.75
Dye
-1.0
Table 4, demonstrated that rib length values rose to +1.0cm and +0.75cm for washed and bleached articles in case of 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting. Growth of +0.5cm and +0.25cm is calculated in washing and dyeing, when 20/150 PCVD Lycra 12.5% knitted at 20/150 PCVD Lycra 8% specs setting. While a contraction of -0.5cm, -0.25cm is observed in bleached, dyed articles for 20/150 PCVD
Table 7. EFFECT OF LYCRA %AGE ON FOOT WIDTH:-
Setting
Elastomaric Yarn
Process
Foot Width (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+0.5
Bleach
+0.5
Dye
+0.25
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
-0.5
Bleach
0
Dye
-0.5
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
0
Dye
0
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
0
Dye
0
Table 7, showed that foot width values rose to +0.5cm, +0.5cm and +0.25cm in washing, bleaching and dyeing respectively for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting. While a decline of -0.5cm in both washing and dyeing is observed for 20/150 PCVD Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting. Further more, no contraction or expansion is experienced in case of 20/150 PCVD Lycra 8% and 20/150 PCVD Lycra 12.5%.
Table 8. EFFECT OF LYCRA %AGE ON BOARD FITTING:-
Setting
Elastomaric Yarn
Process
Board Fitting (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+1.5
Bleach
+1.5
Dye
+1.5
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
-1.2
Bleach
-1.2
Dye
-1.1
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+2.5
Dye
+2.0
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
-1.5
Dye
-2.0
The present research work shows that, in case of 20/150 PCVD 4 % lycra specs settings, the board fitting for 20/150 PCVD 6 % lycra was +1.5 cm for washed, bleached and dyed articles. Analogous tendency observed when 20/150 PCVD Lycra 12.5% runs for knitting at 20/150 PCVD Lycra 8% specs setting i.e. expansion of +2.5cm and +2.0cm in washing and dyeing. It showed that if lycra % age increases, stretch values increases which cause loose board fitting.
Where as, in case of 20/150 PCVD 6 % lycra specs settings, board fitting for 20/150 4 % lycra was -1.2 cm for bleaching and washing, while -1.1cm for dyeing. Which showed that as lycra % age decreases stretch also decreases and board fitting was tight. Further more, above claim also argued by the results of board fitting i.e. -1.5cm and -2.0cm in washing and dyeing for 20/150 PCVD Lycra 8%, when runs at 20/150 PCVD Lycra 12.5% specs setting.
RESULT AND DISCUSSION:
The test result values regarding different parameters i.e. Welt stretch, rib stretch, body stretch, rib length, rib width, foot length, foot width and board fitting are elaborated in given tables as follows.
Table 1. EFFECT OF LYCRA %AGE ON WELT STRETCH:-
Setting
Elastomaric Yarn
Process
Welt Stretch (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+1.0
Bleach
+0.5
Dye
+0.25
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
-0.25
Bleach
-0.5
Dye
-1.25
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+0.75
Dye
+1.75
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
-1
Dye
-1
From Table 1, it is found that welt stretch values increased to +1.0cm, +0.5cm and +0.25cm in washing, bleaching and dyeing respectively for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting. Furthermore, also increased to +0.75cm and +1.75 in wash and dye articles for 20/70/1 NCVD Lycra 12.5% at 20/70/1 NCVD Lycra 8% specs setting. Where as decreased to -0.25cm, -0.5cm and -1.25cm in washed, bleached and dyed articles respectively, when 20/150 PCVD Lycra 4% knitted at 20/150 PCVD Lycra 6% specs setting. Moreover, tightening of -1.0cm is detected in both wash and dyed cases for 20/70/1 NCVD Lycra 8% at 20/70/1 NCVD Lycra 120.5% specs setting.
Table 2. EFFECT OF LYCRA %AGE ON RIB STRETCH:-
Setting
Elastomaric Yarn
Process
Rib Stretch (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+1.5
Bleach
+0.25
Dye
+1.0
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
0
Bleach
-0.75
Dye
-1.0
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+1.5
Dye
+1.0
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
Not applicable
Dye
Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting and -0.75cm, -1.0cm in washing, dyeing for 20/150 PCVD Lycra 8% knitting at 20/150 PCVD Lycra 8% specs setting like wise.
Table 5. EFFECT OF LYCRA %AGE ON RIB WIDTH:-
Setting
Elastomaric Yarn
Process
Rib Width (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
0
Bleach
-0.25
Dye
-0.5
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
0
Bleach
-0.25
Dye
-0.25
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
NA
Dye
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
Dye
Table 5, pointed up not only a shrivel of -0.25cm, -0.5cm in bleaching and dyeing for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting but also -0.25cm in both dyed and bleached articles for 20/150 PCVD Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting.
Table 6. EFFECT OF LYCRA %AGE ON FOOT LENGTH:-
Setting
Elastomaric Yarn
Process
Foot Length (cm)
20/150 PCVD Lycra 4%
20/150 PCVD Lycra 6%
Wash
+1.25
Bleach
+1.0
Dye
+0.25
20/150 PCVD Lycra 6%
20/150 PCVD Lycra 4%
Wash
-0.75
Bleach
-0.5
Dye
-0.5
20/70/1 NCVD Lycra 8%
20/70/1 NCVD Lycra 12.5%
Wash
+0.75
Dye
+0.5
20/70/1 NCVD Lycra 12.5%
20/70/1 NCVD Lycra 8%
Wash
-0.5
Dye
-1.0
Table 6, represented that foot length values not only increased for 20/150 PCVD Lycra 6% at 20/150 PCVD Lycra 4% specs setting to +1.25cm, +1.0cm and +0.25cm in washing, bleaching and dyeing. But also for 20/150 PCVD Lycra 12.5% (when knitted at 20/150 PCVD Lycra 8% specs setting) to +0.75cm and +0.5cm in washing and dyeing. While a contraction of -0.75cm, -0.5cm and -0.5cm is observed for washed, bleached and dyed respectively for 20/150 PCVD Lycra 4% knitting at 20/150 PCVD Lycra 6% specs setting. This kind of contraction is detected as -0.5cm and -1.0cm in washed and dyed articles, when 20/150 PCVD Lycra 8% knitted at 20/150 PCVD Lycra 12.5% specs setting as well.
CONCLUSION:
It is concluded that:
v As lycra % age increases from required, the specs and stretches increase which cause loose board fitting.
v As lycra % age decreases from required, the specs and stretches decrease which cause tight board fitting.
v The process type also effects specs and board fitting in this sequence
Wash< Bleach < Dye.
v Finally, it is accomplished that specs and board fitting will not disturb if lycra % age not exceed the range of ± 0.5 against required % age.