Research On Printing And Dyeing Of Black Fabrics

 

Black can be tested for blackness by defining a color space. In the RGB color space, black is defined as the weighted sum of red, green, and blue being 0. Therefore, the density can be tested by measuring the component value of each color.

However, in the CMYK color space, black is not a color, but any one of the four channels is set to 0. Therefore, to test the density, the following steps are required:

Prepare test equipment, such as spectrometer or colorimeter.

Connect the test equipment to the computer and use RGB color space for color mapping.

Use the test equipment to measure the value of each color channel.

Compare the measurement results to determine which channel is black and which channel is not black.

No matter which test method is used, the same principle can be used to test the density.

To define black, you need to define it as a value of 0 in the color space. Therefore, you need to measure the value of each color channel to determine which channel corresponds to black.

These two scenarios are not identical. In the absence of light in the universe, our universe looks black because no light reaches our eyes. But on the earth's surface, when the light shines on the ground, it will reflect, scatter and penetrate, and finally reach our eyes. So the color of the object we see is not completely dark, but the color of the object illuminated by light. On the surface of the earth, black usually means that the object is not illuminated by enough light, or there are flaws or stains on the surface of the object.

Therefore, the scenes of the universe and the earth's surface are different, but they both have scenes illuminated by light.

Dyeing black fabrics in the textile industry is usually not black enough. How to solve this problem?

The method of darkening the fabric has nothing to do with whether the surface of the fabric is uneven, because the influence of light refraction has nothing to do with the surface shape of the fabric.

To make the fabric darker, the following methods can be used:

Use higher power ultraviolet radiation: ultraviolet radiation can heat fabrics to make them darker. The use of ultraviolet radiation can enhance the expressiveness of dyes to black without damaging the fiber structure of fabrics.

Use of dark dyes: dark dyes can absorb and reflect ultraviolet rays more than light dyes, so higher power ultraviolet rays can be used when using dark dyes to enhance the expression of dyes on black.

Use of fabric care agents: some fabric care agents can help reduce light refraction, thereby enhancing the reflection and absorption of ultraviolet rays by the fabric.

It should be noted that the use of ultraviolet radiation and fabric care agents should pay attention to safety to avoid harm to human body and the environment.

At the same time, different fabrics have different reflective and absorptive capacities to ultraviolet rays, so it is necessary to understand the characteristics of fabrics before operation.

Dyeing black fabric is not a simple thing, it will have a certain impact on the color, resulting in the color is not even or black enough. Here are some possible solutions:

Add more pigment: You can add pigment in the dye solution or add additional pigment to dye the black fabric. This method can produce darker colors, but the quality and cost of pigments will also increase.

Adjust the dye formula: change the dye formula and add some mixed dyes, which may make the fabric darker. However, this method requires a certain understanding of the characteristics of each dye, and the quality and cost of mixed dyes will also increase.

Use darker exercise dyes: exercise dyes are relatively inexpensive dyes that can be used to practice black dyeing techniques. However, this dye may have quality problems, and improper use may lead to uneven color or fading of the fabric.

Fading treatment: for some lighter fabrics, you can use fading treatment to dye black. Before dyeing, fade the fabric first, and then put the fabric into the dye solution for dyeing, which can control the depth and uniformity of color.

The above are some possible solutions. The specific blackening method needs to be selected according to the actual situation.

The damage of dyes to health and environment can refer to the following information:

Effects of dyes on health

Dye itself is a chemical substance, which will have a certain impact on human health. Different kinds of dyes and methods of use will have different effects on health. For example, sulfur black dye is a common dyeing method, which can make clothes darker, but may release harmful substances during use.

It should be pointed out that dyes are not omnipotent and cannot solve all environmental pollution problems. When using dyes, it is necessary to choose environmentally friendly dyes and pay attention to the use method to reduce the impact on the body.

　　 Influence of dyes on environment

The use of dyes will also have an impact on the environment. During the use of dyes, harmful substances may be decomposed, such as toxic gases carbon dioxide (CO2) and volatile organic compounds (VOC), which will have adverse effects on human beings and the environment. At the same time, the use of dyes may also have an impact on the ecosystem. For example, some dyes may affect the health and behavior of animals and cause them to die or escape.

In order to maintain health and protect the environment, we need to choose environmentally friendly dyes and pay attention to the use of dyes to reduce the impact of dyes on the environment.

The discrimination of black fabrics is generally based on visual observation, and can be checked according to the following aspects:

Color: The color of black fabric can be distinguished by using different light sources or observing the surface reflection. Some black fabrics may reflect more light, while others may absorb more light, so it may be difficult to distinguish them in some cases.

Texture: The texture of black fabric can be distinguished by observing whether its surface is obviously rough or smooth. Some fabrics may form many textures or patterns on the surface, while others may be smoother.

Texture: Black fabric can be distinguished by observing its weight, fiber direction and whether it is easy to deform. Some black fabrics may be stronger and more durable than others.

Brand and model: some black fabrics may come from different brands and models, so it can be distinguished by observing the brand and model of the fabric.

To distinguish black fabrics, it is necessary to consider many factors, including color, texture, texture, brand and model, and make comprehensive judgment to distinguish different fabrics.