Thermoforming Considerations for Meeting European Union Single Unit Dose Regulations
Publication Date: 2015-Jun-23
The IP.com Prior Art Database
EP 1311429 B1: PATENT [+7]
There is concern about the accidental ingestion of liquid laundry detergent soluble unit dose (SUD) capsules by children. Because of this concern, the European Union (EU) approved EU Regulation 1297/2014. SUD capsule producers can control a number of processing parameters so they can comply with EU Regulation 1297/2014. Producers must also control the environmental conditions of their processing plant so that the properties of the water soluble films and the SUD capsules are not negatively affected.
MonoSol Technical Bulletin: Thermoforming Considerations for Meeting EU SUD Regulations
There is concern about the accidental ingestion of liquid soluble unit dose (SUD) laundry detergent capsules by children. Because of this concern, the European Union (EU) amended CLP (Classification Labeling Packaging) Regulation 1272/2008 with EU Regulation 1297/2014. EU Regulation 1297/2014 was published on December 6, 2014 and it went into effect on December 26, 2014. Companies producing liquid laundry detergent SUD capsules must comply by June 1, 2015. If companies produced and shipped non-compliant capsules prior to June 1, 2015, then they have until December 31, 2015 to remove the non-compliant capsules from store shelves.
EU Regulation 1297/2014 adds three new CLP requirements to the soluble film of the liquid laundry detergent capsule. First, the soluble film shall “contain an aversive agent (such as a bittering agent) in a concentration which is safe, and which elicits oral repulsive behavior within a maximum time of 6 seconds.” Second, the capsule shall “retain its liquid content for at least 30 seconds when the soluble packaging is placed in water at 20C.” Third, the capsule shall “resist mechanical compressive strength of at least 300 Newton under standard test conditions.”
With regards to the first requirement, MonoSol, LLC offers water-soluble films with denatonium benzoate, a well-known aversive and bittering agent recommended by the EU.
With regards to the second requirement, it is well established that thicker films will take more time to dissolve than thinner films. It is also reasonable to assume that thin areas in the capsule wall should be avoided so that the 30 second requirement can be met. Therefore the process of making thermoformed capsules must be well controlled so that there are no thin areas in the capsule walls.
With regards to the third requirement, thin areas in the capsule wall should also be avoided so that the 300 Newton requirement can be met. Therefore the process of making capsules must be well controlled so that there are no thin areas in the capsule walls. Strong seals between the top and bottom films of the capsule, via heat or water solution processes, are also necessary for meeting the 300 Newton requirement.
Practitioners skilled in the art of making thermoformed single unit dose capsules routinely control the following parameters in order to make capsules that do not contain thin spots:
· Temperature of the film: “The baseline objective for all heating is to create uniform heating throughout the sheet but this is hard to achieve.” (Throne, 2008, p.101). Non-uniform temperatures in the film will lead to non-uniform stretching, which will lead to thick areas and thin areas in the capsule walls. Also, “when the film is heated, the plastic material will yield to natural thermal expansion, loss of crystallinity, and relief of molecular orientation, all of which tend to...