Anti UV Finishing of Cotton Fabric Composite
2016-02-05 08:31 | writer: admin
1, UV finishing agent dosage of UA - 20
Dye with selective absorption of light. A part of light absorption dye can be extended to the ultraviolet wavelength range, which can improve the ultraviolet protective properties of fabrics. Because UA-20 is a water dispersible polymer ultraviolet absorbent, oneself do not have functional groups reacted with the hydroxyl groups on the cellulose fibers, it by adsorption on the surface of the fiber, endowed with excellent anti UV effect fabric. The UA-20 has a maximum adsorption capacity on the cotton fabrics, more than the adsorption capacity is difficult and fiber combination. Anti UV, anti crease finishing also so.
2, The influence of processing methods on anti UV effect
Using the whitening cotton fabric were anti UV / DP and anti ultraviolet shit soft one bath finishing according to the process, the influence of different processing methods on the anti UV finishing effect.
It can be seen from Figure 2, anti ultraviolet finishing agent UA-20 was less than 10 g/L, DP anti UV effect fabric is higher than the softening finishing of fabric; the dosage of UA-20 is greater than 10g/L, anti UV effect better softening finishing of fabric. The content of UA-20 is low, easy care finishing resin shrinkage body can be combined with the cellulose molecular chain adjacent hydroxyl groups on the occurrence of a covalent bond, the molecular chain of the adjacent connected to each other, the relative slip limiting fiber molecules, thereby reducing the gap fiber internal molecular, lower UV transmittance line. The affinity of UA-20 fiber is better than that of resin affinity to fiber, with the increase of the dosage of finishing, higher doses of softening finishing of fabric attached to UV, so anti UV effect is better.
3, The influence of fluorescent whitening agent for anti UV effect
Whitening use the same organization specification and unbleached fabric, anti ultraviolet feces were soft one bath finishing, effects of fluorescent whitening agent on the anti UV effect. Fluorescent whitening agent can absorb ultraviolet below 400nm, the maximum absorption wavelength of 360 ~ 380nm (in the UVA band), so, fabric brightening defence ultraviolet ray effect is high, and the transmittance in the UVA than in the UVB band low. Fluorescent whitening agent can convert energy absorption of radiation, 400 ~ 500nm of purple or blue fluorescence, impart the fabric whitening effect.
4, Anti UV fabric washing resistance
According to the process of fabric respectively whitening anti UV / DP one bath finishing and anti ultraviolet shit soft one bath finishing, anti ultraviolet finishing agent UA-20 content 30g/L. Whether it is soft finishing or finishing fabric, after washing the anti UV effect similar change rule, that is washed 5 times anti UV effect is improved, the increase of the UPF value; then, the value of UPF decreased gradually, after washing 30 times gently. This is because the fabric in the process of fiber is stretched, produce shrink after washing. Shrink the fabric density and fabric tightness becomes larger, the porosity decreases, through ultraviolet is reduced, so the defence ultraviolet washing 5 times better. With the increase of washing times, finishing agent was washed to remove not firmly with anti UV, anti ultraviolet fabric effect gradually worse. After 50 times washing, softening and finishing of the fabric UPF value decreased by 7.4% and 5.8% respectively, are within acceptable limits.
5, Light fastness
According to different color cotton fabric, anti ultraviolet finishing can improve the fabric color fastness to sunlight. White fabric and grey fabric improves the degree of maximum, can improve the grade 1.5, other colors can be improved by 1 grade, anti ultraviolet, soft light fastness is better than one bath finishing fabric UV / DP finishing. This may be because after ultraviolet finishing, fixation on the fiber anti ultraviolet finishing agent on the ultraviolet absorption and reflection, and energy as heat exchange, or other harmless low-energy radiation energy release or consumption, avoid dyes produce photochemical reaction, so as to improve the light fastness.