Flame-retardant fabrics are flame-retardant treatments based on dyed fabrics, or flame retardants with flame-retardant functions are added to the fiber through polymer polymerization, blending, copolymerization, composite spinning, and extrusion modification techniques. , Make the fiber flame retardant. The finished product can effectively prevent the spread of flames and protect the original properties of the fabric. It can automatically extinguish or effectively slow down the spread of flames, so that the fabric is carbonized to form an isolation layer, and it has the characteristics of insoluble dripping and non-flame when exposed to fire. , Has a good flame retardant effect. (The flame retardant fabric is not unignitable, even if it is ignited by an open flame, it can be automatically extinguished within 12 seconds after leaving the open flame)
1. Classification of flame retardant fabrics
The flame retardant fabrics can be divided into:
1. Permanent flame-retardant fabric (weaved with flame-retardant fiber, no matter how many times it is launched, the flame-retardant effect will not change)
2. Washability (more than 50 times) flame retardant fabric
3. Semi-washable flame retardant fabric
4. Disposable flame retardant fabrics (decoration, curtains, cushions, etc.)
2. The production process of flame-retardant cloth and the method of introducing additives can be divided into: flame-retardant treatment of fiber and flame-retardant finishing of fabric
Flame retardant treatment of fiber:
1. The flame retardant mechanism refers to adding a flame retardant to some inherently combustible filaments (such as polyester, cotton, acrylic) to inhibit free radicals in the combustion process; or to change the thermal decomposition process of the fiber to promote Dehydration and carbonization; some flame retardants decompose and release non-combustible gas to cover the surface of the fiber to isolate the air.
2. Flame retardant treatment method
1) Improve the thermal stability of fiber-forming polymers
2) Flame retardant modification of raw silk
Flame retardant finishing of fabric:
1. Flame retardant mechanism
1) Covering layer theory: The flame retardant can form a glass-like or stable foam covering layer at high temperature, which has heat insulation, oxygen barrier, and prevents combustible gas from escaping outward, and plays a flame retardant effect.
2) Non-combustible gas theory: flame retardant decomposes non-combustible gas when heated, and dilutes the concentration of combustible gas from cellulose to below the lower combustion limit.
3) Endothermic theory: the flame retardant reacts with endothermic reaction at high temperature, reducing the temperature to prevent the spread of combustion. In addition, the heat can be quickly transferred out after the fabric is finished, so that the cellulose cannot reach the temperature of fire.
4) Chemical reaction theory (catalytic dehydration theory): the flame retardant reacts with the fiber as a Lewis acid at high temperature to make the fiber catalytically dehydrated and carbonized, reducing the production of combustible gas.
2. Flame retardant finishing method
1) Padding and baking method: the most widely used in the flame retardant finishing process. The technological process is padding-pre-baking-baking-post-treatment. The padding liquid is generally composed of flame retardants, catalysts, resins, wetting agents and softeners, and is configured as an aqueous solution or emulsion for finishing.
2) Dipping and baking method (exhaustion method): the tissue is immersed in the flame retardant liquid for a certain period of time, and then dried and baked to make the flame retardant liquid be absorbed by the fiber aggregate.
3) Organic solvent method: non-water-soluble flame retardant is used, which has the advantage of low energy consumption during flame retardant finishing. But in actual operation, pay attention to the toxicity and flammability of the solvent.
4) Coating method: The flame retardant is mixed into the resin, and the adhesion of the resin is to fix the flame retardant on the fabric. According to different mechanical equipment, it is divided into knife coating method and pouring coating method.