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Application of Dyes and Pigments |
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Colourants
for Security Printing Dyes for Packaging Sector Dyes in Concrete Industry Pigments in Paints Industry |
Dyes for Packaging Sector
The packaging and board sector a highly specialized
section of the paper industry has a great demand for the dyestuffs. This
increasing demand is backed by the replacement of traditional basic
dyestuffs with highly advanced and modified basic and direct dyes.
Traditional Basic dyes enjoyed an unrivalled position for a considerable
number of years due to a lot of factors, important among them are high
colour strength, acceptable properties and a more or less modest pricing.
But over the years, other dye types, that includes the Direct dyes have
tilted the scale of economy in its favour as the perfect choice in the
packaging sector.
- Hue and depth of target shade
- Necessary technical properties like lightfastness
- Base colours and types of the furnish
- Laws governing environment
- Cost factors
The following table highlights the comparative
advantages, disadvantages of the three types of dyes used in the packaging
sector namely Basic dyes, Modified Basic dyes and Aninic Direct Dyes.
| Dye | Advantage | Limitation |
| Basic dye | Substantively is moderate | Poor lightfastness |
| Above par tinctorial strength | Not so good shade stabilty | |
| Is economical | Acid content is high | |
| Diverse shade range | Backwaters coloured | |
| Preferential Dyeing | ||
| Modified Basic dye | Very good Substantivity | Shade range is somewhat limited |
| Backwaters are cleared | Lighfastness through better than basic dyes, but still not up to the mark | |
| Coverage of all the fibres | ||
| Light fastness is better than basic dyes | ||
| Anionic Direct Dyes | Good substantivity | Somehow limited build-up on some furnishes |
| Llightfastness is moderate to good | ||
| Not expensive | ||
| Broad shade |
The dyes find application in the following popular
packaging sector:
- Newsprints
- Sacks
- Egg boxes
- Carton board
- Fibre board
- Kraftliner
- Cationic size press formulations
- Anionic size press formulations
