pvp coating ink industry application

The application of PVP in organic pigments:

The organic pigment particles obtained by chemical synthesis method have a large specific surface range, the specific surface is 8-100m2/g, and the usual mechanical treatment method can only make the pigment particle size reach 70-100 microns, and can not be directly used. Therefore, people use surface treatment technology to change some properties of the pigment, such as dispersion, thermal stability, solubility resistance, chemical inertness and optical solid properties. In fact, the surface treatment of pigments is to use some method to prevent the particles from growing before the pigments gather into large particles, and the best way is to protect the pigment particles and give them the required performance.

PVP has good film forming properties, soluble in water and insoluble in some organic solvents, most of the substances used in pigment solvents make organic solvents, and PVP has better film forming properties with the increase of molecular weight. When the solubility of organic solvents is poor, PVP(molecular weight greater than 30000) is used to treat pigment particles. Due to the affinity between PVP and pigment molecules, a transparent film is formed on the surface of the pigment. The formed film is not soluble in organic solvents, so it is not easy to be destroyed. And it can improve the luster and dispersion of the pigment, cut off the contact between the organic pigment and the external environment, and indirectly give the chemical stability and thermal stability of the organic pigment, avoid the chemical reaction caused by some substances or photothermal with the external environment, and improve the photosolid properties of the pigment. PVP for the surface treatment of organic pigments is generally PVP-K30, PVP-K90 or PVP-VA64. The particle size of organic pigment after PVP treatment is between 0.1-10 microns. The amount of PVP is generally 5-10% of the mass of organic pigments. The main pigments available for PVP surface treatment are: protective and decorative coatings, such as varnish, paint, etc.; Aqueous dispersion system; Printing, ink, fabric coloring and plastic coloring, latex, etc.

The excellent dispersion performance of PVP can also be used for the dispersion of carbon black, phthalocyanine pigments, titanium dioxide and other pigments.

The application of PVP in coating:

In emulsion coatings and water-soluble resin coatings, the coloring effect is reduced due to the poor dispersibility of pigments and the condensation precipitation during storage, and there are bad phenomena such as floating color and poor luster. The addition of medium molecular weight PVP (PVPK30) can improve the coloring power, eliminate the floating color phenomenon, disperse and stabilize the pigment composition, improve the luster, and avoid the flocculation precipitation of the pigment. The viscosity of the emulsion coating with styrene and methacrylate as the main body is often very low, resulting in poor water resistance of the coating, the fluidity of the coating is too large, the thickness of the film is not easy to control, and the hardness is not enough, and it will fall off, so it needs to be thickened and viscosified. In this category

By adding appropriate amount of PVP into the emulsion, the viscosity of the emulsion can be increased by more than 10 times by evaporation and concentration, and a stable synthetic resin solution with high viscosity can be obtained. The coating prepared with PVP adhesive coating emulsion has the advantages of non-hanging, good water resistance, hard film, no shedding, stain resistance and so on.

The paper transparent coating containing PVP makes the printing ink dry quickly on it, has good ink absorption, insoluble in water, and has good coagulability and diffusivity. In addition, PVP has important uses in other coatings, such as conductive coatings, electrode coatings, and anti-leakage coatings. For example, the insulating layer outside the conductive material, after repeated sudden heat, sudden cooling, sun and rain, will age or break, or leak electricity because of water seepage. A layer of PVP film (PVPK90) is formed on the outside of the insulation layer. On the one hand, the PVP film is transparent and does not affect the natural color of the insulation layer. On the other hand, the PVP film and the insulation layer are formed

Bonded together, the insulation layer is isolated from external light, heat, rain, etc., to avoid leakage caused by water leakage, reduce the aging speed caused by light and heat, extend the service life of the wire, and increase the hardness of the wire appropriately.