Does anyone know the principle of cotton fabric finishing-easy ironing finishing?

In fact, it is non-ironing finishing, also called durable press finishing (PP), non-ironing finishing, washable and wear-resistant finishing, and shape memory finishing. Non-ironing finishing includes two meanings: "shrink-proof and wrinkle-resistant" or "durable pressing". For example, pants should not only be shrink-proof and wrinkle-resistant, but also keep wrinkles after washing.

There are two processing methods for fabric finishing: pre-curing and post-curing. Pre-curing, that is, the fabric is impregnated with resin in open width, and the whole process of open width curing is completed by the printing and dyeing factory. This process is simple and easy to process, which can obtain a flat appearance and a non-ironing effect, but it brings some difficulties to garment processing, and it is difficult to give some wrinkles and garment shapes to garments. Moreover, due to the different shrinkage rates of sewing thread and cloth in washing, it is often prone to shrinkage (wrinkling). This process is suitable for the finishing of thin fabric shirts.

The other is post-baking, which can be divided into grey cloth padding and clothing impregnation according to the different ways of padding resin. The former is that the pure cotton fabric is soaked in resin in the printing and dyeing factory and then dried, and the clothes are sewn and put into the oven to complete the resin crosslinking reaction. This process is mostly used to finish coats, trousers and other clothes with thick fabrics. The advantages are that the clothes are flatter, the size is more stable, lasting wrinkles can be obtained, and the seams are very flat. The disadvantage is that it is often difficult to properly control the storage conditions of finished fabric semi-finished products during transportation. If the resin is crosslinked too early, it will be difficult to correct it later.

Super soft finishing and gas phase finishing are both resin finishing, and their baking process is after clothing. The biggest feature is that the trousers can be kept for a long time without uneven seams. For example, super-soft finishing, also known as SSP (super-soft process), is characterized by multiple complementary processes to achieve perfect wearing effect. The technological process is: fabric → bleaching → liquid ammonia treatment → resin finishing → clothing → baking. Liquid ammonia is liquid ammonia, which is different from ammonia, not an ammonia solution. The viscosity and surface tension of liquid ammonia are much lower than that of water, so liquid ammonia can penetrate into cotton fiber easily and quickly, change the crystal structure of cotton fiber, and come out quickly and easily without damaging the fiber. Resin finishing and liquid ammonia finishing are combined, and their functions complement each other, realizing the real crease-resistant and non-ironing finishing of pure cotton fabric.

Stage finishing, also known as VP (steam treatment), is also cured after sewing clothes. Different from the super-soft finishing process, cotton fabric is directly modified with formaldehyde and sulfur dioxide gas. Different from ordinary resin materials, gas phase method is characterized by cheap raw materials, good effect, soft hand feeling, good hygroscopicity and durability. This technology is still very suitable for shirts and clothes. At present, there are not many intermittent gas phase finishing processes and equipment used in China, which are usually produced by garment factories. Ningbo Youngor Company uses this method to produce non-ironing shirts.

There is also AP finishing, which is an advanced performance finishing, which was invented and patented by BASF company. In order to overcome the shortcomings of dry and wet crosslinking process, this process adopts simple dry crosslinking method to achieve the same advanced finishing effect as wet crosslinking method. Its technological process is: dipping resin → drying to normal water content (5% ~ 8%) → drying.

In addition to technological innovation, some new technologies are also being introduced into non-ironing finishing. If nano-TiO2 _ 2 is used instead of sodium hypophosphite, it can not only reduce the pollution of phosphorus-containing compounds to the environment, but also achieve good non-ironing effect in maleic acid-acrylic acid-butyl acrylate polybasic acid finishing system. In this paper, the mixed finishing solution of citric acid and maleic anhydride was used to finish cotton fabric with nano-catalyst SiO2 _ 2. After finishing, the crease recovery angle of the fabric is obviously improved, and the breaking strength is not greatly reduced. Nano-materials will play an increasingly important role in crease-resistant finishing of cotton fabrics in the future because of their special properties such as small particles, large specific surface area, strong surface activity and good dispersibility. In addition, foam finishing, steam flash explosion technology, radiation graft copolymerization and plasma technology all provide new ideas for crease-resistant finishing of cotton fabrics.