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K. S. Kulkarni and R. Adivarekar
1.1 Discontinuous or Batch-Type Systems
All the operations are carried out batchwise. It usually involves loading the machine,
carrying out the treatments following a predetermined cycle, unload the machine
and finally wash it thoroughly before starting a new cycle. This working process
is extremely flexible and is suitable for processing small lots. For producing larger
lots, the discontinuous process becomes labour-intensive and uneconomical. It also
entails long processing times and results may vary from batch to batch.
1.2 Continuous Systems
The operations are carried out by means of a series of machines; every machine carries
out always and solely the same process. Every machine is assembled according to
specific production requirements. A system like this entails high start-up costs and
a complex setup but once the system has started, it requires a smaller staff and
grants excellent repeatability and high output rates; continuous systems are therefore
suitable for manufacturing large lots of products with the highest cost-efficiency.
1.3 Semi-continuous Systems
In these mixed systems, several operations are carried out with both continuous and
discontinuous machines. For example, a continuous pad-batch machine is used to wet
the fabric and a discontinuous system is then used for other treatments. These mixed
systems are suitable for processing small and medium lots; they require reasonable
start-up costs and grant quite good reproducibility.
The wet processing of textiles involve pre-treatment, colouration and finishing.
Pre-treatment involve removing of natural as well as added impurities from the
textile substrate and making it uniform in terms of absorbency with good degree
of whiteness. Colouration involves dyeing and/or printing, while finishing consists
of applying various finishes, which can be divided into chemical and physical finishes. Different softeners, speciality finishes like wrinkle free, oil and stain repellent
etc. are chemical finishes and calendar, sanforizer etc. are physical finishes.
K. S. Kulkarni and R. Adivarekar
1.1 Discontinuous or Batch-Type Systems
All the operations are carried out batchwise. It usually involves loading the machine,
carrying out the treatments following a predetermined cycle, unload the machine
and finally wash it thoroughly before starting a new cycle. This working process
is extremely flexible and is suitable for processing small lots. For producing larger
lots, the discontinuous process becomes labour-intensive and uneconomical. It also
entails long processing times and results may vary from batch to batch.
1.2 Continuous Systems
The operations are carried out by means of a series of machines; every machine carries
out always and solely the same process. Every machine is assembled according to
specific production requirements. A system like this entails high start-up costs and
a complex setup but once the system has started, it requires a smaller staff and
grants excellent repeatability and high output rates; continuous systems are therefore
suitable for manufacturing large lots of products with the highest cost-efficiency.
1.3 Semi-continuous Systems
In these mixed systems, several operations are carried out with both continuous and
discontinuous machines. For example, a continuous pad-batch machine is used to wet
the fabric and a discontinuous system is then used for other treatments. These mixed
systems are suitable for processing small and medium lots; they require reasonable
start-up costs and grant quite good reproducibility.
The wet processing of textiles involve pre-treatment, colouration and finishing.
Pre-treatment involve removing of natural as well as added impurities from the
textile substrate and making it uniform in terms of absorbency with good degree
of whiteness. Colouration involves dyeing and/or printing, while finishing consists
of applying various finishes, which can be divided into chemical and physical finishes. Different softeners, speciality finishes like wrinkle free, oil and stain repellent
etc. are chemical finishes and calendar, sanforizer etc. are physical finishes.