Candidate Support Pack - Scottish Qualifications Authority

The finishing characteristics of polyester cotton garments are similar whatever the weight
of fabric used. It is important that they are washed correctly, with a carefully controlled
temperature cool-down period built into the wash process. The rate of temperature
reduction from the maximum wash temperature must not exceed 4 °C per minute until the
work is below 50 °C, to avoid thermal shock creasing.
The wash process must also be formulated to overcome polyester’s attraction to oily
soiling. Sufficient detergent and temperature must be used to remove the soiling or the
high drying temperature of the tunnel finisher will ‘burn-off’ any remaining oil and grease,
causing fumes and a potential fire risk.
Mixing a proportion of cotton with the polyester helped to overcome customers’ objections
to polyester garments that were uncomfortable to wear in hot weather and cold in winter,
with a tendency to be charged with static electricity.
The advantages to launderers of using garments made from polyester cotton far outweigh
these disadvantages. The fabric is far less absorbent than cotton, making it quick drying
during wear and processing. It is hardwearing and available in lots of vibrant colours
that resist fading during repeated processing.
Cotton rich ‘challenger’ garments
Increasing the proportion of cotton to 65 per cent with only 35 per cent polyester has
produced a second generation of polycotton garments that are warmer to wear, more
absorbent and appeal to customers who require a heavy duty garment — for example,
engineers.
These garments can be finished in a tunnel finisher, but require a longer extract on the
wash process and may need conditioning in a tumble dryer before finishing due to greater
moisture retention. The use of more cotton in the fabric also increases the problems of
shrinkage.
Cotton garments
Cotton still has a place in the workwear market where the quality of finish is important to
the customer, and they are willing to pay a premium for hand finishing. The benefits of
cotton also include wearer comfort in hot and cold environments and better retention of
special finishes — for example, flame retardant treatment.
The tunnel finisher was developed to take advantage of the qualities of fabrics containing
polyester, and does not produce a quality finish on 100 per cent cotton.
GC8N 22 — Laundry Operations Level 2 9.15