Deinkability Score Impact on EPR Eco Modulation Fees in Recycled Stock
Deinkability scores under INGEDE Method 11 directly determine EPR eco-modulation fee surcharges or discounts on printed recycled paperboard packaging.
Filtrate Discoloration
Chemical Bleed
Measurement of the colour extracted from paper or board when it is soaked in water indicates the release of soluble dyes or organic compounds. This effect, described as filtrate discoloration, shows the level of chemical bleeding that can occur when the material is exposed to moisture.
Process Cause
The presence of unbound dyes, residual lignin, or recycled fibre contaminants in the paper pulp can lead to this staining of the contact liquid. During the papermaking process, if the sizing agents or dye fixatives are not applied in the correct proportions, the chemicals remain loose within the fibre network. When the finished board comes into contact with water, these soluble elements dissolve into the liquid and discolour it.
Product Suitability
Food-grade packaging and high-end printing papers require a zero or minimal level of extracted colour to prevent contamination of the product or the staining of nearby surfaces. Laboratory tests use a spectrophotometer to compare the extracted liquid against a clear water control. If the extraction shows significant colour, the material fails the specification and cannot be used for direct food contact.
This testing is standard for papers used in tea bags, coffee filters, and food wraps where the transfer of chemical agents could affect consumer safety.