The Research Of Vat Dyes With Near-Infrared Camouflage

Recently,as infrared detector techniques make great progress,the war becomes more unilateralism and clarity,general forests and nights don’t have any effect,the security of soldiers don’t ensure success any more.As a result,infrared camouflage techniques are paid attention by countries all over the world.At presence,the camouflage is done mainly by pigments whose process is simple and that can be covered with objects without considering the property of exterior materials,so paints are used on the furnishment of military affairs widely,like plane and tank. Though the coating process is convenient,economical,and its technology is mature,but the feelings of the soldiers would be affected because of the declining of wear performance,such as moisture absorption,permeability,softness of the fabrics.So the use of dyes to achieve near-infrared camouflage becomes trendy topic.In this paper,near-infrared camouflage performance of fabrics would be given by dyeing with vat dyes.Reflectance spectroscopy was used to measure the reflection properties of the leaves and soil background;many factors were discussed about the influence on near-infrared camouflage,such as the additives of the dyeing process,the structures of the dyes,the concentration of the dyes and the structures of the fabric;the crucial dyes for the green camouflage were found out.And the thesis compared the anti-near-infrared properties of some vat dyes from the company of Huayuan and DyStar.In the simulation of green background,cotton and polyester-cotton fabric were discussed separately,and cotton fabric was mainly discussed.The infection of near-infrared camouflage caused by dyeing with different dyes mixed was also analyzed.Firstly,cotton and polyester fibers were discussed apartly in analysis of polyester-cotton fabric.Then the paper generally analyzed the near-infrared camouflage on polyester-cotton fabric dyed with disperse/vat dyes by high temperature and pressure.At the same time,the black dyes and carbon black as additives were analyzed on the performance of near-infrared camouflage,and wet and dry fabrics were researched into anti-near-infrared effect.The dead leaves and soil were simulated respectively in the simulation brown background.Some factors of the effects on near-infrared camouflage,such as the ratio of dyes,the dyeing method and the bath of dyeing, were discussed when the leaves background was mainly analyzed.It was focused on the near-infrared camouflage caused with carbon black by ultrasonic dip dyeing in the simulation of soil background.It was founded that the cotton fabrics,which could be dyed by vat blue 4B(or vat blue CLF), vat yellow GCN,vat olive R and vat grey M,had the ability of near-infrared green camouflage. The near-infrared green camouflage performance could be achieved by using disperse yellow E-3GE,disperse blue ETD,vat blue 4B,vat blue CLF,vat yellow GCN and vat direct black RB for PET fabrics which used high temperature high pressure dyeing.Cotton fabrics which dyed with vat brown BR,vat yellow G,vat olive R,vat red F3B and vat grey M,had the ability of near-infrared brown camouflage.Vat blue 4B and vat blue CLF were two important dyes which played a key role in near-infrared camouflage.As the concentration of dyes increasing,the reflectivity of dyed fabric decreased,but the dosage of dyes was not too much.The anti-near infrared of fabric was not greatly influenced by its structure.And the structure of dyes was the most important influencing factor of the near-infrared reflected spectrum.When the composition of dyes was same,the difference of reflected spectrum was not wide.When the simulation of background,reflectivity of dyed fabrics could be effectively regulated in the visible range when the addition of black dye.While the addition of carbon black could adjust the near-infrared reflectance of dyed fabrics,and the amount of carbon black should be less than 0.5%.In addition, near-infrared camouflage would be also influenced by the extent of wet and dry of the fabric,wet cloth was more helpful to green camouflage.