Objective. Achieve superhydrophobic properties without changing the production process
Nuestro cliente, un fabricante de piezas plásticas, quiere que su producto tenga propiedades superhidrófobas para repeler el agua. Uno de sus requisitos es no modificar su proceso productivo ni añadir ningún recubrimiento o post-procesado. Su producto tiene una geometría compleja y tiene un tiempo de ciclo muy rápido.
Our client, a plastic parts manufacturer, would like that their product to have superhydrophobic properties to repel water. One of its requirements it is not modifying its production process or adding any coating or post-processing. Their product has a complex geometry and has a very fast cycle time.
Solution. Injection mold microstructuring
The first step was to know the client’s production process in order to select the technology that best fit their case. We gave them training on the available technologies, focusing on those that did not change their process as they had asked us. The option we chose is called “In Mold Microstructuration”. With this solution, we microstructure the injection mold using a laser, and during the normal injection itself, the microstructures are transferred to the part. These microstructures are what will provide the functionality, in this case, superhydrophobicity, to the plastic.
The key in these projects is the design of the microstructure. Depending on the shape, height, width and spacing of the microstructure we can obtain some properties or others. In this case, and with our client’s material, we reached 160º contact angle with water.
During the optimization stage in our laboratory, we used interchangeable mold inserts, and injected in the laboratory injector, in this way we were able to really test the microstructures that were designed.
Finally, with the microstructure that had presented the best properties, a final customer mold was microstructured with which final pieces were injected. Several characterizations were carried out on these pieces: contact angle with water, profilometry and confocal to check the correct transfer of the microstructures, abrasion and wear tests, resistance to chemical agents and scratching following the client’s requirements.