Usually the flame-retardant fabrics we imagine are not burnt in the impression of everybody, but in fact, the flame-retardant cloth is not without fire, but is not easily ignited, the burning rate is slow or immediately extinguished after leaving the flame. There are many international flame retardant standards, such as EN470-1, EN531, EN532, NFPA2112, NFPA70E and so on.
Flame retardant fabrics are divided into two types: fiber flame retardant and finishing flame retardant, and finishing flame retardant is divided into one-off and durable flame retardant.
Fiber flame retardant, also known as permanent flame retardant fabrics, is the work done in the early stage of the whole cloth making process. The flame retardant effect of the grey fabric woven with flame retardant fibers is permanent, and can generally be maintained to more than 50 washing times, with good washing effect, especially the flame retardant yarn polyacrylic (commonly known as sub-acrylic). Kri) shrinks and carbonizes in case of fire, extinguishes as soon as the fire source leaves, does not melt or drop black smoke, and does not cause secondary fire. It is usually used for clothing fabrics.
One-off flame retardant fabric is a common fabric treated with flame retardant in later dyeing and finishing. Its biggest disadvantage is that the flame retardant effect disappears or evidently declines after washing. Usually, we should use it in some occasions with less washing times, such as hotel curtains.
Durable flame retardant fabrics are usually produced by proban process. The flame retardant used is a kind of flame retardant for durable finishing of cotton fibers and their blended fabrics. Its main feature is that the fabrics can have good flame retardant ability within 50 washes after finishing with this flame retardant.
Flame retardant cloth is not the cloth that people say does not ignite. It can prevent the spread of flame and extinguish automatically in a certain period of time after special process treatment. Therefore, the criterion for judging the flame retardant property of fabrics is usually based on the burning rate of fabrics. That is to say, the flame-retardant finished fabric contacts with the flame for a certain time according to the prescribed method, then removes the flame, and determines the duration of the flame and flameless combustion of the fabric, as well as the extent of the damage of the fabric. The shorter the flame burning time and the flameless burning time, the lower the degree of damage, the better the flame retardant performance of the fabric; conversely, the worse the flame retardant performance of the fabric.
There are two main types of flame retardant fabrics at present.
The first category is post-finishing flame-retardant fabrics, such as pure cotton, polyester and cotton, etc. The post-finishing of flame-retardant fabrics is mainly the surface treatment of fabrics in the post-finishing process of textiles, so that fabrics have flame-retardant properties. The flame-retardant finishing process of fabrics is simple, less investment, effective and suitable for the development of new products.
The second category is intrinsic flame retardant fabrics, such as aramid, acrylic cotton, Dupont Kevlar, Nomex, PR97 Australia, etc.
The initial flame retardancy of the three fabrics is not much different, but after washing, the one-time flame retardant fabrics completely disappear.