Plastisol ink is a PVC (polyvinyl chloride) based system that essentially contains no solvent at all. Along with UV ink used in graphic screen printing, it is referred to as a 100% solid ink system. Plastisol is a thermoplastic ink in that it is necessary to heat the printed ink film to a temperature high enough to cause the molecules of PVC resin and plasticizer to cross-link and thereby solidify, or cure. The temperature at which most plastisol for textile printing cures at is in the range of 149 °C to 166 °C (300 °F to 330°F).

Plastisol ink can be printed on many items that can withstand the heat required to cure the ink and is porous enough to permit good ink adhesion. They do not dye the threads of a fabric like traditional dye material. Plastisol screen printing ink wraps around the fibers and makes a mechanical bond with the fabric. Screen printing plastisols will not adhere to non-porous substrates such as plastic, metal, wood and glass. They also will not adhere to water-proof nylon material without adding a bonding agent/catalyst.

Plastisol ink is made up PVC particles suspended in a liquid plasticizer, it is very durable, flexible, and is commonly used in apparel printing. Plastisol is thick and opaque and it can be mixed easily to create just about any color imaginable. With plastisol ink, we can create special effects like suede, glow-in-the-dark, glitter, shimmer, or metallic. Plastisol is most commonly used on dark-colored fabrics, and it is ideal when printing designs that are less detailed and very colorful.

The four major components that go into the formulation of Plastisol inks are

(1)Polyvinyl Chloride (PVC)  (2)Plasticizers  (3)Fillers  (4) pigments.

Additives
A word of caution about ink additives, it’s easy to upset the chemical balance of plastisol inks by using the wrong additives, or by adding too much of an additive – even if it is the correct type of additive. The result can be t-shirt ink that never cures properly, a problem that may not be discovered until your customer washes a shirt and the design falls (i.e. color lose, adhesion or cracking). To avoid this problem, use only those additives recommended by the manufacturer, and read the Technical Data Sheets for each ink and additive, and carefully follow their instructions. Never add mineral spirits to plastisol ink. Although mineral spirits will make it easier to print at first, soon the ink will become even stiffer and harder to print than before. Also, it is possible that mineral spirits will prevent the ink from curing properly.

Ink Storage

Store plastisol inks at room temperature. Prolonged exposure to temperatures above 90º F (32º C) can cause the ink to start to cure while it's still in the container.