How to use “Chips”
Chip dissolution is carried out using a simple stirrer of 10 to 20 HP (according to the batch size).
For example for a batch of around 200 kg, 9 to 11 HP, for a batch of around 500/1000 kg – 20HP; use a saw, “cowless” type agitator, with a diameter which is 2/3 of the vessel diameter, running at 900 to 1400 rpm.
The system to be used can be selected from the following:
1. The vessel contains the minimum amount of solvent to dissolve the chip and is stirred. The chips are added slowly at intervals to allow them to dissolve. After 1 to 2 hours, when the chip have dissolved completely, add the remaining formula components and stir for a further 10 to 20 minutes.
2. Or, following chip solution at a high concentration, this intermediate solution is kept for making up final mixtures for specific requirements.
3. The minimum vehicle necessary to dissolve the chip is placed in the vessel (if more than one vehicle is being used, use the least viscous one). The agitator is switched on and the chips are trickle fed to the vessel. After an interval of 1 to 2 hours complete batch preparation by adding the remaining components.
4. In all cases remember that the chips must be dissolved in the minimum amount of solvent or vehicle in order to have a mix of sufficient strenght to ensure the best result. It is important to remember that before completing the product formulation, the chips must be completely dissolved. If this is not the case the required degree of colour gloss, clarity and intensity, will not be achieved.
Dissolving in a single solvent may give rise to flocculation. If this occurs and the flocculated material is used, the main technical qualities of the final product will be adversely affected.