Home>Knowledge>Content

Main performance indicators of fluorescent pigments

Apr 03, 2021

Hiding power:

Refers to when an object is coated with a certain paint, the pigment in the paint can cover the background color of the surface of the coated object, so that the background color can no longer be revealed through the paint.

Hiding power = pigment mass (g) / surface area of the coated object (CM2)

Heat resistance:

It means that under a certain processing temperature, the pigment does not change significantly in shade and tinting strength. It refers to the resistance of the pigment to the change of the tinting strength caused by the processing temperature.

It is worth noting: 1. When considering the high temperature resistance of the pigment, it is also necessary to consider the heating time. 2. What needs to be considered is the thermal stability of the colored resin itself.

Light resistance:

It refers to the color change of the pigment under light irradiation. The light resistance rating is the best in the eighth grade and the worst in the first grade.

Weather resistance:

It refers to the changes of pigments to various forms of climatic conditions, including visible light and ultraviolet light, moisture and temperature, and product color. After organic pigments are irradiated with light, they will cause changes in the configuration of the pigment molecules and other reasons, which will affect the saturation, and even fade into gray or white. The weather resistance of the pigment is rated as level 5, with level 5 being the best.

Migration resistance:

It means that the pigment migrates from the inside of the plastic to the surface of the product or to the adjacent plastic product and solvent. In the assessment, a level of 5 means no migration, and a level of 1 means severe migration.

The specific performance is as follows:

① Blooming: During storage at room temperature, pigment particles migrate from the plastic/pigment system to the surface.

② Solvent bleed: The pigment component enters the adjacent solvent, dyes and some organic pigments show this kind of phenomenon.

③ Plastic/plastic contact migration.

Oil absorption:

It refers to the amount of refined linseed oil absorbed by the pigment sample under specified conditions, which can be expressed by volume/mass or mass/mass. The amount of oil absorption has a certain effect on the leveling and gloss of the coating.

Solvent resistance:

It means that after the pigment and the solvent are in contact, the solvent will stain because some pigments are dissolved in the solvent. The solvent resistance of a pigment refers to the ability of the pigment to resist the dissolution of the solvent and cause the solvent to stain.

Softening Point:

The temperature at which a thermoplastic resin changes from a solid state to a sticky state is called its softening point. If the softening point is too low, the product is easy to agglomerate; if the softening point is too high, the injection temperature must be increased, otherwise the pigment will be difficult to melt and cannot be dispersed.

Decomposition point:

The temperature at which the resin is destroyed and decomposed at high temperatures is called the decomposition point. The decomposition point can reflect the thermal stability of the resin.

Particle size:

Particle size is an important indicator reflecting the size of fluorescent pigment particles, and the unit is um. The finer the particle size, the easier the product is dispersed and melted in downstream products.


Send Inquiry