What is Dye ink and its application?
Dye ink generally refers to water-soluble ink, but in fact, solvent-based inks made of alcohol-soluble/oil-soluble dyes are also available. Pigment ink is insoluble in water, so it needs to be superfinely dispersed before it can be applied. The ink produced with pigment has a narrower color gamut and darker color, but the black ink does not have sharp characters, no burrs, and is waterproof and lightfast.
Due to the simple production process of dye inks and the low cost of dyes, most manufacturers of compatible consumables use black dye inks instead of pigment inks, which can save costs without requiring too much technology. Most of the current black dye inks have carcinogenic ingredients-benzidine (IARC Class I carcinogen, with strong carcinogenic effects, is an intermediate in dye synthesis, and the incubation period in the human body is 10-20 years).
The consumable manufacturers know that benzidine and its derivatives are carcinogens. After the human body is exposed to or absorbed, the azo group will be broken with the body’s metabolism, and the dye will be re-dissociated to liberate carcinogenic intermediates, causing direct harm to the human body, but it is driven by benefits. And market influence is still in mass production.
Original inkjet printer manufacturers use pigment black ink for basic black, and almost all color inks use dye ink.
It is made of dyes/solvents (mainly water) and various additives, such as moisture absorbents, surfactants, dispersants, antioxidants, corrosion inhibitors, acid-base stabilizers, light stabilizers, etc.
The color is bright and pleasing to the eye. Commonly used colors are: magenta, pure blue, yellow, black and other colors. In order to enhance the performance of transitional colors and grayscale tones, light pink/light blue/medium gray/light gray are added to make the color of the print Richer and more rounded.
The requirements of water-soluble dye inks for dyes are
(1) Good water solubility;
(2) Strong tinting power;
(3) Bright and pure color;
(4) The aqueous solution is stable and does not deteriorate;
(5) The color is firm and weatherable.
The dyes used in the manufacture of water-soluble inkjet are mainly acid dyes and direct dyes.
Inks made with water-soluble dyes have poor fastness. Mainly the light fastness and oxidation-reduction fastness, because of the excellent re-solubility of water-soluble dyes, this type of ink is not water resistant.
Acid dyes are characterized by bright colors. The disadvantages are poor light fastness, high color migration (migration), and prone to bleeding. After the print is placed for 2-3 weeks, the color and the color contact edge will be blurred, resulting in a third color Decrease the quality of printed parts. The cost of inkjet made with acid dyes is lower. Low-cost inkjets mostly use acid dyes as colorants.
Direct dyes have relatively large molecular weights, low migration, high light fastness, no halo and bleeding, high definition of prints, and storage time more than ten times longer than acid dye prints.
The cost of inkjet using direct dyes as colorants is much higher than that of acid dyes. All high-end inkjets on the market use direct dyes as colorants.
Dye inks are molecular-level fully-dissolved inks with a diameter of 1~2 nanometers. The probability of ink head blocking is very small. It is easy to be absorbed by the material after printing, and it is printed on flat and smooth paper. It has a good light radiation performance. Therefore, the ability of color reproduction is relatively strong, the printed image is colorful, and the cost is low; but because the dye ink is not protected by a layer of polymer on the surface like the pigment ink, the molecules are easy to decompose under harsh conditions. Causes fading.