Polyester yarn

dope dyed spun polyester yarn

Is there a way to improve the blackness of polyester fabric dyed black?

Why the blackness of polyester fabric dyed black is not ideal

When pure polyester fabrics are dyed with disperse dyes, especially filament fabrics, they always look bright and white after dyeing. Increasing the dye concentration will not help, and the fastness will be greatly reduced.

There are two reasons for the low Blackness:

One

The section of polyester fiber is smooth and round, and the reflection of light is more specular, that is to say, white light is more concentrated, so it does not look black.

Two

The refractive index constant of polyester fiber is the largest among all fibers. For example, the refractive index of wool is 1.553, that of silk is 1.598, that of viscose is 1.577, that of nylon is 1.580 and that of polyester is 1.725. Objects with high refractive index have high reflectivity. The reflected light is reflected by white light, so it looks white.

In addition, high reflectivity means less light is absorbed, so the color depth is not large.

Resolvent

For this reason, some people have tried to apply a material with low refractive index on the surface of the fabric, so that the refractive index of the fabric is reduced, the reflectivity is also reduced, and the blackness is increased. The resin polymer with low refractive index is mainly acrylic compound, which can form a polymer film on the surface of the fabric.

After treated with this kind of resin polymer, the fabric depth index is obviously increased, and the visual depth can be increased by more than 20%.

processing method

After dyeing, the fabric can be soaked or dried. The bath ratio is 1:30, the temperature is 80 ℃, the time is 30 minutes. After the application of high polymer, not only the blackness is increased, but also the color brightness is improved, the luster is soft, the durability is good, and the color light is unchanged.