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Pigments are coloured, organic or inorganic compounds
that are used for colouring in numerous critical industries. Pigments
are known to give a full and vibrant range of colours. This section
delves on the various facets of the pigments to give a better
understanding. |
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What is Pigment
Pigments are generally coloured, organic or inorganic
solid powder, and usually are insoluble. They are not affected physically or
chemically in the substrate in which they are incorporated. Pigments can
give a full range of colours. Pigments have a variety of applications that
includes plastics, ink, and coating applications.
- Excellent light and weather fastness
- A good baking stability that makes them suitable for automotive and other industrial paints
- High tinting strength
- Good over spray fastness when applied in paints
- Gives heat stability of around 300° C in the case of Polyolefins Plastics
- Excellent solvent resistance properties
- Easily dispersible
- Consistency and uniqueness of shades
While choosing a pigment depends on application,
following broad factors can be taken as a guide:
- Hiding efficiency
- Color
- pH value
- Bulking value
- Density
- Refractive index
- Hardness
- Oil absorption
Comparison of Pigment Families
| Property Behavior |
Inorganic Pigments |
Classical Organic Pigments |
Specialty Organic Pigments |
Organic Dyestuffs |
| Opacity | Usually high | Translucent to Transport | Very Transparent | |
| Colour Strength | Low to moderate | Considerably stronger than Inorganic Pigments | Strongest | |
| Dispersability | Usually Good: Often Abrasive | Adequate | Poor to good | Not required; Soluble |
| Heat Resistant | Usually 5000 F; Some 2000 C | 1500 C-3000 C | 2000 C- 3000 C | 2500 C- 3500 C |
| Migration resistance | Excellent | Moderate -Good | Good - Outstanding | Very Poor - good |
| Light Fastness (on a Blue scale | 6 to 8 | 2 to 6 | 6 to 8 | 2 to 7 |
| Weather resistance | Outstanding for selection | Insufficient | Excellent for Selection | Good for selection |
