Nowadays, plastic materials are the most used raw material in the toy sector, because of its good adaptation to any designs, physic-chemical characteristics, easy processing and low cost. Elastomeric polyolefins, and especially elastomeric polyethylene (PE), give excellent mechanical stiffness properties and very low hardness. Due to these particular properties, these materials are appropriate for the toy and childcare articles manufacturing.
One of the most relevant difficulties for its application in some sectors is the decorating and painting issues of pieces made up of PE. In the polyolefins painting, for example, its surface energy is noticeably lower to wet the surface and remain unchangeable on it during the product’s useful life. The surface treatment tries to adequate the substrates in a way that allow them to be used for painting, metallization, printing or the substrate adhesion. In the specific case of painting, this process is done by increasing the energy of the material for it to be higher than the energy of the painting (or the blending with solvents, whose surface energy must be similar).
Suny Martínez, the project coordinator states: “the modification of the polymers surface by means of low pressure plasma treatment presents several advantages against others mechanical or chemical surface treatments, as it does not give heat, it is quick and environmental non-aggressive and it allows the modification of the complex geometry of the piceces, as they are introduced in the reaction chamber where the treatment is made in an homogeneous and controlled way. That is why the plasma treatment acceptation has increased in industrial applications”.
The low pressure treatment efficiency depends on the different experimental parameters, like the time of treatment, the plasma generation power and the partial pressure of the plasma generator gas, among others. The study carried out by AIJU has proved how the elastomeric PE painting properties have deeply improved by means of low pressure plasma surface treatment, in few seconds of treatment.
Some of the results obtained were presented in the 16th International Symposium on Plasma Chemistry in Taormina (Italy).
The Toy Research Institute (AIJU.info) is a non-profit organization located in Ibi, the Spanish geographic centre for toys manufacturing. Its aim is to transfer and allow toy manufacturers the access to the knowledge of new technologies in order to improve their competitivity, while offering technological and financial assessment and supporting the professional development of people involved in the sector.
The 75 professionals on the staff carry out with their labour in the different areas AIJU is made up of, and this organization is provided with the required infrastructure to manage the different activities it undertakes.
AIJU is made up of 580 partners belonging, highly, to Valencian industry. From the total number of partners, 40% are toy manufacturers, 42% belong to the auxiliary industry and the rest belong to other sectors.
The department intended to carry out these tasks is the Product Development – Laboratory. Within this department, one of the most interesting innovation fields is rapid prototyping. AIJU has been working on the research of SLS Equipment for 10 years now, studying its feasibility of use in the manufacturing of functional prototypes and mould prototypes with the objective of reaching final material sets.
AIJU is an active member of the Rapid Manufacturing European Platform and the Spanish mirror led by ASERM, the Spanish Rapid Manufacturing Association. It is also member of EuMAT and Manufuture. AIJU is member of the “Materials” group promoted by REDIT between the RDT Centers of IMPIVA’s Network.
In the standard field, the entity is working on the potential feasibility of the proposed rules as well as new safety criteria for toys, with participation in several proficiency testing schemes both on a National and European Level. Thus, it is participating in the development of new standards concerning organic additives in materials for toys in the European Committee of Normalization (CEN).