According to the statistics of international fire control department, there are 6 million to 7 million fires worldwide every year, and residential fires account for more than 80%, among which bedding, household decoration cloth and clothing are the main causes of fires. Textile clothing and human direct contact, once burned, the light part of the skin burns, suffering pain, the heavy part of the skin burns, life-threatening. In addition, the harmful gas produced by the burning of textiles also endangers people's lives, such as carbon monoxide, carbon dioxide, nitrogen oxides, ammonia and aldehydes, etc., which can cause suffocation or death due to poisoning.
The so-called flame-retardant textile refers to the textile or textile made of flame-retardant fiber after flame-retardant finishing, varying degrees of reduced flammability, in the combustion process can significantly slow down its combustion rate, and leave the source of fire can quickly self-extinguish, and less release of toxic smoke, so as to have non-flammability of textile.
At present, flame retardant textile finishing technology
Textile flame retardant fiber flame retardant and fabric flame retardant (that is, fabric finishing). Compared with the production of flame-retardant fiber, flame-retardant finishing is flexible, which can endow the fabric with flame-retardant property according to the final use requirements of the product, and can be combined with other finishing such as waterproof, antibacterial, antistatic and other finishing for multi-functional finishing, the process is simple.
The flame-retardant finishing method of fabric should be determined according to its structure, end-use and flame-retardant performance. Generally, there are four finishing processes:
1. Impregnation and drying method
Impregnation and drying method, also known as absorption method, is to soak the fabric with finishing solution containing flame retardant for a certain time and then dry, so that the flame retardant is soaked in the fiber, the flame retardant and the fiber molecules are adsorbed by van der Waals force. Generally speaking, the flame retardant effect obtained by soaking and drying method is not durable. The flame retardant agent is easy to fall off after washing, and the fabric loses the flame retardant effect.
2. Dip rolling baking method
The technological process of dip - rolling - drying - drying - washing treatment. Pad also generally by flame retarding agent, crosslinking agent, catalyst, additives and surfactants, rolling over rate according to the types of fabric, flame retardant performance requirements to determine, drying at 100 ℃ or so commonly, baking temperature according to the types of flame retardant agent, crosslinking agent and fiber
3. Coating method
The coating method is to mix the flame retardant agent into the coating agent, through the coating machine coating agent applied on the surface of the fabric, after drying the coating agent cross-linked film, flame retardant evenly distributed in the coating film, play a role in flame
retardant, when the flame retardant is insoluble in water or flame retardant and fiber macromolecules can not form a cross-link when the coating process can be used.
4. Continuous spray method
Continuous spray method is generally used in large curtain, carpet, etc., in the last process of the manual spray method to do flame-retardant finishing. Additional to the fabrics with fleecy decorative pattern to the surface, tufted pile, nap, if use dip roll method to be able to make surface nap decorative pattern receives injury, also use successive spray method commonly.
Test method for flame resistance of textiles
1. 45-degree combustion test method:
For samples placed in a 45-degree direction of ignition, the time required for the flame on the sample to burn up for a certain distance is measured, or the time for the reburning and smoldering of the sample after combustion, the damaged area and the damaged length are measured, or the number of times the flame needs to be relieved when the sample burns to a certain distance from the lower end of the sample. The method is applicable to the flammability test of textile products. The following standards are: ASTM D1230, FTMS 191-5908, CFR 16 Part1610, CAL IF TB117, NFPA702, GB/T 14644.
2. Horizontal combustion test method:
The flame spread distance and time were measured for the horizontal sample from ignition to standard time, and the flame spread rate was used to characterize the flame retardant characteristics of the fabric. The method is suitable for testing all kinds of textiles, especially automotive interior fabrics. ISO 3795, FMVSS 302, DIN 75200, SAE J369, ASTM D5132, JIS D1201, AU169, FZ/T 01028.
3. Vertical combustion test method:
The flame retardant characteristics of textiles were evaluated by igniting the samples directly below the vertically suspended sample strips and testing the reburning time, smouldering time and damaged length or area of the samples. The method is suitable for testing the combustion characteristics of children's clothing, decorative fabrics, laminated fabrics and coated fabrics. The standards met are ASTM D6413-99, CALIF. TB-117, GB/T 5455, and CPAI-84.