Formaldehyde-free Durable Flame-retardant Finishing Of Cotton Fabrics And Its Effect On The Color Of Dyed Fabrics

Cotton fabric has excellent wearability and is widely loved by the public,but its limiting oxygen index is only 18%,which is very flammable.It is easy to become the fuse of fire and spread the fire,which causes the loss of people's property and lives threat.Therefore,it is very important to impart semi-durable or durable flame-retardant properties to cotton fabrics according to different places of use.Durable cotton fabric can withstand 50 or more times of washing and soaping and still has a good flame-retardant effect.There are many flame-retardant cotton fabrics on the market today,but there are problems such as high formaldehyde content,poor flame-retardant effect and poor durability.Research on non-formaldehyde,durable,efficient,and green flame-retardant cotton fabric is the direction that scientific researchers have been working hard on.This article uses nitrogen-containing organic phosphate ester flame retardant JN-FR to finish cotton fabrics,explores the influence of different factors on flame retardant finishing,analyzes the best finishing process and related mechanisms,and examines the effects of flame retardant finishing on colored cotton fabrics.The color change law and color fastness are discussed.Apply flame retardant finishing to industrial production.The flame retardant JN-FR is used for flame-retardant finishing of cotton fabrics,and the finishing process is optimized by combining the two performance indexes of fabric strength and damage length.And the best flame-retardant finishing process is obtained: the amount of flame retardant JN-FR01 is 450 g/L,the dosage of the catalyst JN-FR02 is 10 g/L,and the baking temperature and time is 165 ? and 2 min.After testing,the damage length of the flame-retardant cotton fabric is 7.3 cm,the strength retention rate is 81.7%,and the damage length after 50 washings is still less than 17.8 cm.At the same time,flame-retardant finishing dyed cotton fabrics also obtained significant flame-retardant effects.Flame-retardant cotton fabrics are analyzed by EDS,SEM,TGA and XRD.The results showed that the crystal form of cotton fiber did not change.The surface of the flame-retardant cotton fabric does have substances attached,and the structure of the solid residue of the cotton fiber remains intact after full combustion.The residual carbon content of flame-retardant cotton fabric after pyrolysis increased by 29.95%,the maximum weight loss rate of thermal pyrolysis was reduced by 10.14 %/min compared with non-flame-retardant cotton fabric,and the decomposition rate was slowed down.This shows that the flame-retardant effect of flame-retardant cotton fabric is mainly occurs in the condensed phase zone.When the best flame-retardant finishing process was applied to fabrics dyed with reactive dyes,it was found that cotton fabrics dyed with different dyeing depths,different colors,and different types of dyes showed different degrees of color changes,but all showed increased brightness of the dyed fabrics.The color becomes lighter.Therefore,in actual production,it is necessary to select a suitable flame retardant finishing process according to the type of dye and the specific color requirements.Flame-retardant finishing will not only cause color changes to the dyed cotton fabric itself,but also cause color changes in subsequent washing or abrasion.In order to explore the influence of formaldehyde-free durable flame-retardant finishing on the color fastness of dyed fabrics,this paper analyzes the color fastness to soaping,rubbing,perspiration and water fastness.The study found that the color fastness to soaping of cotton fabrics of different colors after flame-retardant finishing is about 4,the dry rubbing color fastness is mostly 4-5,the wet rubbing color fastness is mostly 3,perspiration color The fastness is grade 3-4,and the color fastness to water can reach grade 4.The results show that the dyed cotton fabric still has excellent color fastness after flame-retardant finishing.The dyed fabrics with 8 kinds of reactive dyes are screened out and the color fastness is higher after flame retardant finishing.