We’ve had quite a lot of lovely Sun recently, however it’s still a bit chilly overnight and there has been a frost in some parts. Printers must be aware of the potential that emulsion can freeze it stored incorrectly.
Emulsions that have gone off if they have one of the following characteristics;
- It gells into a ball or has a thick rubbery consistency
- It may separate into different layers or not mix fully
- It may feel and look grainy
If your emulsion is a two part mix, and it’s been frosty, your diazo may also freeze. If the diazo has frozen then thawed there will be moisture in the bottle, if this is the case, the diazo has gone bad and you will need a new bottle.
If you think the emulsion has survived the cold check by giving it a good mix then letting it settle for 3-4 hours. This will release any air bubbles and allow you to test coat a screen.
With the Amex Emulsion we provide we suggest to keep it in its original container between 15°C and 25°C. Once mixed it will last for up to 8 weeks.