The difference between pu pigment and dye is that the coloring method of the object is different. The dye can penetrate into the inside of the object for coloring, such as the inside of the fiber; while the PU pigment can only act on the surface of the object, such as the surface of cloth. details as follows:
PU pigment: It is some white or colored fine powdery substance, generally insoluble in water, oil and solvent media, but can be evenly dispersed in it. The pigment has good tinting power, hiding power, and bright color. The coloring function of the color is that the fine pigment particles are evenly dispersed on the surface of the material and penetrate into the texture of the wood to make the wood grain clear. If more color is left on the surface of the wood, it will cover the wood grain. Pigment is the secondary film-forming substance of colored paint. In the wood decoration process, primer, putty and wood coloring are prepared, and pigments are often used. Opaque colored paint has some color and hiding power due to its paint film. At the same time, the pigment can also enhance the durability, weather resistance, and abrasion resistance of the coating film.
Dyeing agent: different from pigments, dyeing agent is an organic substance that can be dissolved in liquids such as water, alcohol, oil or other solvents, which can make fibers or other materials quite solid and colored. It can be called a soluble coloring substance, so it can be formulated Homogeneous dye solution. The dye solution can penetrate into the wood and have a complex physical and chemical reaction with the constituent materials of the wood (cellulose, lignin and hemicellulose), which can color the wood without blurring the texture of the wood, and make the wood dyed bright and firm. s color. Since the dye particles have been dissolved and dispersed, the dye solution should generally be a uniform transparent liquid with a color. When the dye solution color wood, it has no covering property, but it has permeability and will not blur the wood.
PU pigments are insoluble in organic solvents and can only be dispersed in resins and other media, and dyes can be dissolved in solvents.
coloring agent is more bright, but the coloring power is poor, and the stability is not good at the same time.
Dyeing agents are mainly divided into alcohol-soluble and oil-soluble, and there are many classifications. Since the dye itself is soluble in water or organic solvents, the color will re-dissolve and become unstable in the presence of water or solvents. The color and gloss of the pigment are better.
Pu dyeing agent imparts color to the colored medium in a molecular state, and its properties are mainly related to its molecular structure; while pigments are colored in a particulate state, and its properties are not only related to molecular structure, but also related to its physical state.