Textile finishing operations are a part of the fabric ennobling operations; let’s start from the definition of “textile ennobling“:
For textile ennobling we mean the set of treatments aimed to transform the raw fabric into semi-finished products suitable for subsequent processing, or in finished fabric ready for the manufacture of products.
The finishing of a fabric includes all those treatments to which the fabrics are subjected at the end of the ennobling operations. These treatments are designed to improve the appearance, the hand, the properties, also according to the possible fields of use.
With finishing it is therefore meant the set of chemical, physical and mechanical treatments to which the fabrics are submitted in order to give them the specific properties for the use for which they are intended.
Textile finishing is carried out both on fabrics made with digital printing and on traditional printed ones, and also on dyed fabrics. Depending on the process, it can be useful on woven and knitted fabrics.
Modern textile finishing and finishing treatments are chemical-physical processes. In addition to the historical mechanical treatments, we use chemical solutions specially designed and suitable for the purpose you want to achieve. The most used physical means in modern finishing are:
The use of chemical substances with particular physical processing conditions allows to obtain very different results, it is therefore necessary to create a finishing recipe that represents the historical memory of the processing one and allows its reproduction. The finished fabrics are submitted to a series of tests, in order to verify the achievement of the desired results.
The textile finishing operations alter the structure of the fabrics to make various types of improvements, depending on the type of fabric and depending on the use to which it is intended. The objectives are therefore:
Some treatments improve the structural quality of the fabric, while others make aesthetic improvements to make it looks more pleasing or adapt it to the needs of fashion.
The main parameters that lead to the choice of the most suitable type of textile finishing are:
Following are some of the main textile finishing treatments:
With this treatment a glossy, smooth, compact effect is obtained by means of friction, pressure and heat. In some cases it is possible to opt for the use of steam during the process (wet calendering)
Polishing: it is a type of calendering, carried out through the use of special calenders that exploits the action of heat, friction and, if necessary, polishing auxiliaries.
This operation is also a particular type of calendering that allows the engraving of a design on the fabric.
Through the use of a cylinder covered with abrasive material, a softer and more insulating fabric is obtained, due to the raising of the surface of the fabric.
Used to give the fabric greater thermal insulation by lifting the surface hair. To achieve this result mobile cylinders with curved needles are used in various motion with respect to the fabric.
This operation cuts off the surface hair of the fabric with special cutting parts.
Through the use of a flame, the surface hair of the fabric is eliminated (by burning it).
Through the action of the heat combined with the mechanical action of rubbing and compression of the fabric, it changes the structure, the compaction and the re-entry of the wool.
The treatment of cotton fabric with a strong caustic alkaline solution in order to improve the hydrophility thus saving dyestuff during syeing process, the shine of fabric, the hand and other properties.
By applying mechanical and steam forces, the fabric is dimensionally stable. Sanforizing is the finishing process to treat textile fabrics to prevent the dimensional alteration of warp and weft. It is also called anti-shrinkage finishing process. It is normally used for cotton fabrics mainly and also for some other textiles made from natural and synthetic fibres. It is a method of stretching, shrinking and fixing the woven cloth in both length and width, before cutting and producing to reduce the shrinkage which would otherwise occur after wash.
Through the use of dry or overheated saturated steam, the glossy effect of the fabric is eliminated, the surface is regularized and the fabric dimensions stabilized.
Some finishing treatments require the use of chemical solutions of different nature, thanks to which it is possible to give a fabric some properties that would be impossible to achieve using only mechanical processes such as those described above as, for example, making fabrics with chemical finishes stable, or confer waterproofing or fireproofing properties on otherwise devoid of fabrics.
The products used in chemical finishing processes can be natural (glues, greases, oils, starches), artificial (modified starches, modified cellulose) or synthetic (synthetic products).