Since the 21st century, in order to adapt to market demand, non-iron finishing has required the development of high-count thin shirt fabrics. Based on the traditional rolling and baking process, some new process technologies have been developed one after another.
Tide cross-linking
Moisture cross-linking is a finishing process in which a cross-linking reaction occurs between the no-iron finishing agent and cellulose at low temperatures when the cellulose fiber is in a partially expanded state (that is, when the fabric contains a certain amount of moisture). The moisture cross-linking process can give cotton fabrics good wet wrinkle resistance, medium-level dry wrinkle resistance, and its non-iron grade is high; at the same time, it has less wear resistance and strong damage after finishing. In recent years, it has been used in thin, high-end shirt fabrics and other Product applications have been favored by colleagues in the industry. However, tide cross-linking has shortcomings such as long process flow, low production efficiency (intermittent type), and difficult to control the process. Due to the increasing application of tide cross-linking process in production, a new continuous process has also been introduced.
Mild (or low temperature) baking process
Mild baking process , it was first used as an improved process for the pre-baking and durable pressing (PP) finishing process. The purpose is to improve the cross-linking of fibers in the dry state during high-temperature baking in the traditional process, so as to improve the distribution and distribution of cross-linking. The main principle of improving wet wrinkle resistance is to use a stronger catalyst so that cross-linking can be completed at a lower temperature (generally 100 to 120°C, not exceeding 130°C). At present, this process has been successfully used in the production of high-end thin cotton non-iron shirt fabrics and bedding textiles. Some people believe that the mild baking process may be the most powerful candidate to replace the moisture cross-linking process. The famous BASF company also applied for a patent for “Advanced Performanes Finishing” (AP bonding process for short). The process flow and equipment used in the mild baking process are exactly the same as those in conventional rolling and baking, except that the process technical parameters are different.
It is said that dry cross-linking is the way to achieve the finishing effect of tide cross-linking, and its advantages are as follows:
(1) The process is simple, easy to operate and easy to control;
(2) Good dry/wet wrinkle recovery and washable W&W properties;
(3) Comfortable and soft feel;
(4) Small force damage;
(5) Fabric’s The release of formaldehyde meets environmental protection requirements (<75ppm);
(6) Fabric yellowing is lower than traditional dry cross-linking;
( 7) It seems to have no significant effect on all dyes and optical brighteners.
Rolling and baking
After decades of continuous improvement, chlorine absorption The problems of yellowing and chlorine loss have been solved, and it is no longer a problem to release the amount of toxin that meets the requirements of environmental protection standards. Only in order to obtain a certain level of iron-free performance, a certain degree of strength and wear resistance must be sacrificed, and there is no proper compensation method. Although under normal circumstances, most of the strong damage caused by cross-linking is temporary, while a small part may be permanent damage caused by high temperature and acidity.
The trial results show that the wrinkle resistance of non-iron finished cotton fabrics will gradually decrease during the wearing and washing process, but at the same time the strength will gradually increase: after several times After washing, it may even exceed that of unfinished cotton fabrics that have been similarly worn. It is an indisputable fact that normal non-iron finishing of cotton fabrics will not affect the actual wearing performance. However, reducing the strong damage caused by iron-free finishing and improving wear resistance are still the unremitting goals of chemical finishing technicians.
In 2005, the U.S. Cotton Company stated that “Tough Cotton”, a durable cotton pressing finishing product produced using a new method, is characterized by a stronger fabric. , more durable, attracting the attention of colleagues around the world. According to the introduction, the process flow is a traditional padding and baking process, only the composition of the padding fluid is different from the traditional padding fluid.
Since its invention, anti-wrinkle finishing has been accompanied by the development of varieties of cross-linking agents, and researchers in textile chemical finishing are always looking for more suitable cross-linking agents and establish optimal processing conditions for them and cellulose fibers in order to obtain better anti-wrinkle properties; at the same time, we spare no effort to use softeners, lubricants, elastomers, etc. from fine chemical products as additives for anti-wrinkle finishing to enhance the finishing The effect and elimination of some undesirable side effects, such as rough feel, reduced strength and wear resistance, and continuously improve the physical level of anti-wrinkle finishing fabrics.
</p
