Basic knowledge about pigments




Colored substance that has an affinity to the substrate to which it is being applied. Synthetic colorants Characteristic of dyestuff is know through it’s brilliant color at low concentration and transparency of the colorant. However due to it’s solubility in the medium, it could not be used in some thermoplastic polymers such as polyethylene, polypropylene.

Inorganic Pigment

Inorganic pigments are crystals of natural or synthetic metal oxides, sulfide or other salts used as a coloring agent for plastics, paints and inks. This structure is extremely stable, therefore inorganic pigments have excellent properties such as light fastness, weathering fastness, heat stability, migration,..etc. Typical inorganic pigments used in plastics such as TiO 2, Fe 2 O3, ZnS, PbCrO 4 , ..etc

Organic Pigment

are chemical synthetic with carbon based molecules manufacture chemicals, usually under intense heat and pressure. They are often most saturated and strongest tinting colorants. However their properties such as light fastness, heat stability could change dramatically depending on the particle size, crystal form or the type of substrate used. Typical organic pigments used in plastics such as Phtalocyanine pigments, Diarylide pigments, Chinacridone pigments Azo pigment

Color shade acceptance

Standard procedure for preparing the comparison samples

  1. Use approved standard
  2. Use same let down ratio
  3. Use same surface type
  4. Use same polymer
  5. Use same processing method and condition

Color shade comparison method

  1. Visual
  2. Spectrophotometer

Heat Stability of the Masterbatch

Heat resistance test of color based DIN 53772


Light fastness of the Masterbatch

Light fastness test in accordance to DIN 53388 Test result will be compared against the blue scale

  •  Maximum Maximum Light fastness fastness is 8 = Good UV resistance resistance
  •  Minimum Light fastness is 1 = Poor UV resistance



Migration test in accordance to DIN 54002

  1. Prepare the test sample
  2. Cover the sample with white PVC sheet
  3. The test sample will be insert in the oven for 2 hours at 120 °C with a load of 5 kg on top. ? 3. The test sample will be insert in the oven for 2 hours at 120 °C with a load of 5 kg on top.
  4. After 2 hours, the sample will be put in the desiccator
  5. The test sample will be evaluated.

                                    Light fastnes

Warpage of the final product

Cause of warpage of the final product

Slow temperature set down of the final product, causing uneven temperature gradient throughout the molded body.

Warpage phenomena is also caused by some organic pigments, mold design, processing condition and processing machine.


Rheology of the Masterbatch

The melt flow index or MFI is a measure of the ease of flow of the melt of a thermoplastic polymer. It is defined as the mass of polymer, in grams, flowing in ten minutes through a capillary of a specific diameter and length by a pressure applied via prescribed alternative gravimetric weights for alternative prescribed temperatures.

The MFI will be measured in accordance to ASTM D123 8

Extrusion Plastometer and testing condition in accordance to ASTM D1238


Dispersion and Distribution of the Masterbatch

Dispersion of Pigment

Pigment dispersion is necessary so to obtain optimum tinctorial strength, cleanliness of shade and good gloss on the final product. Poor dispersion of the pigment or pigment agglomerates could be notice as dark dots on the surface of the final product



Pigment Dispersion

Distribution of Pigment

Pigment distribution is to be understood as homogeneous dissemination of the pigment particles in the final product. Uneven distribution of the pigment could be seen as color streaks or flow lines on the surface of the final product.

Distribution Pigment

Distribution Pigment 2

Poor distribution Pigment

High Volume Products

Standard White

Standard Black

Printing Industries: 

Ink, Printing Machine, Printing Auxiliaries

Plastic Industries:

Plastic Packaging Machine, Tube Machine, Others