Printing ink composition
Screen printing ink is composed of pigments, binders, fillers and auxiliary agents of composition, which is composed of several free through reconcile, ground into ink.
Table:
|
Screen |
Coloring | pigment | Divided organic pigments, inorganic pigments natural and artificial inorganic pigments. |
| dye | Divided water-soluble fuel, dye dissolved in a solvent and oils. | ||
| Binders | Natural resins | Divided rosin, shellac, rubber, gum arabic and the like. | |
| Synthetic resin | Alkyd, epoxy, acrylic liquid resin; rosin modified series, phenolic modified series, synthetic rubber, polyamide, etc., petroleum, and other solid epoxy resin. | ||
| Vegetable oil | Including tung oil, seed oil, linseed oil. | ||
| Solvent | Series include alcohols, esters series, fatty series, petroleum-based solvents and the like. | ||
| Filler | Natural filler | Such as terrazzo powder. | |
| Artificial filler | Such as barium sulfate, calcium carbonate, colloidal calcium carbonate, magnesium carbonate and the like. | ||
| Adjuvants | Such as driers, suppression to agents, plasticizers, defoamers, emulsifiers, stabilizers, anti-settling agents, curing agents, leveling agents. | ||
Printing inks classification
A wide variety of screen printing inks, the classification method is varied. But there are several ways to look at the major categories
1, according to the characteristics of the ink Category:
It can be divided into fluorescent ink, light ink, fast fixing ink, magnetic ink, conductive ink, scented ink, UV drying ink, sublimation ink, transfer ink.
2. The ink was status classification:
A. colloid ink: water-based ink, oil ink, resin inks, starch paste, etc.
B. Solid Ink: screen printing electrostatic toner.
3. The printability Category:
A. Paper ink: oily ink, aqueous ink, high light-based inks, half light-based inks, evaporative drying type ink, natural drying inks, coatings matrix printing ink, plastic synthetic paper-based inks, paperboard cartons ink.
B. fabric ink: water-based ink, oil ink, emulsion ink,
C. Wood ink: water-based ink, oil-based ink.
D. plastic ink: PVC ink, ink polystyrene, polyethylene, ink, acrylic ink, polypropylene ink.
E. metallic ink: aluminum, iron, copper, stainless steel and other special inks of different metals, including evaporation drying, oxidative polymerization type, two-liquid reaction type ink.
F. leather ink.
G. glass ink: glass instruments, glass crafts inks.
H. ink printed circuit boards: an electrically conductive ink, ink corrosion resistance, and resistance to fluorine and alkaline plating ink
I. ceramic glassware ink
4, according to the ink dried form Category:
A. evaporation drying type ink (including water-based ink)
B. oxidative polymerization type ink.
C. two liquid reaction type ink.
D. heat curable ink.
E. ultraviolet curable ink.
F. electron beam radiation drying ink.
About the type of printing ink
1, two liquid reaction type ink and features:
When printing a mixture of resin and hardener ink called two-liquid reaction ink. This ink multi-use epoxy system resin, curing agent using more ammonia class. The advantages are: solvent composition is very small, the adhesion of various materials are relatively good, the ink film is hard and tough, with a strong oil resistance, solvent resistance and heat resistance. The disadvantages are: since the two solutions are mixed after the reaction began, so the printing process, the viscosity of the ink gradually increases, and after mixing of the ink can not be saved.
2, heat-curing ink and features:
Premixed resin and hardener, the resin is heated after the printing, to form an ink film, the ink becomes heat curable ink. This resin with a single liquid type epoxy resin ink system, they bear the characteristics of film, although almost no different with two liquid-based inks, but the flexibility of a film but a lot of difference, since the ink hardly at room temperature the reaction, therefore, when printing relatively easily over the second liquid ink. But it must be more than 150 ℃ high temperature barbecue, ink is also more difficult long-term preservation.
3, an ultraviolet curable ink and features:
Ink drying process, by ultraviolet radiation, the resin polymerization reaction, the formation of the ink film, this ink is called an ultraviolet curable ink (i.e. UV ink). UV ink is composed of pigment, a prepolymer, a crosslinking agent, a photoinitiator, additives and other components, the main use of this ink system prepolymer-modified acrylic photopolymerizable a photosensitive resin, the sense of rotation of single body, photopolymerization initiator, pigments and additives are mixed together, make sense of rotation of the resin to form an ink film in accordance with the principle of photo-polymerization. A little: UV inks do not use any solvent in the printing process does not produce solvent evaporation, is conducive to environmental protection and human health workers, good stability in the printing process, drying speed, save energy, film glossy, color density reproducibility better than ordinary ink has excellent abrasion resistance, water resistance, oil resistance and solvent resistance and the like. Three out ultraviolet ink (100 ℃ above). Nonflammable, relatively safe to use. OK: the site does not shine at the end of the ultraviolet curing, part black part and the reflected light from a curing light absorbing more slowly, not on what kind of material can be bonded, the ink costs are higher.
4, fluorescent ink and features:
Screen printing with fluorescent inks are fluorescent pigment as a coloring material making ink. Fluorescent pigment is modulated by the fluorescent optical rotation of the fuel and synthetic resin. Ink particle size between 5-15 microns.
Screen printing with fluorescent ink suitable for printing paper category and ethylene film. Fluorescent ink sheet oxidation drying and evaporation drying type two. Yixi film evaporation using fluorescent ink drying.
When using fluorescent ink note the following:
① As the fluorescent ink Poor resistance to rotation, is not suitable for long-term outdoor use, outdoor use and therefore should not use fluorescent ink screen prints.
② fluorescent inks suitable for about 200 mesh screen.
③ amount of ink after printing 50-60 g / m, its hair color and resistance to rotation is ideal.
④ When the substrate is transparent objects, printing fluorescent ink should be preceded by a white ink printing, which can improve the fluorescent effect. Typically fluorescent ink is easily confused with the luminous ink, and can be distinguished by comparing the characteristics of the two inks.