Project

Oleophobic microstructuration for plastic

We design the oleophobic microstructures, laser mark them on the injection mold, transfer them by injection and characterize them. These properties reduce the contact between the plastic part and the oil.

Microestructuracion-oleofoba-ATRIA

Objetive. Reduce contact between the oil and the plastic part

Our client, a manufacturer of plastic automotive parts, wants to improve the properties of one of its plastics. Their objective is to improve their ability to repel a certain type of oil, since they degrade the material over time. This entails an expense since premature failure implies the replacement of parts. If we manage to avoid or reduce contact between the oil and the part, we will also avoid premature aging of the part.

Solution. Microstructuring the injection mold with oleophobic microstructures

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 to do.

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 functionality, in this case, oleophobicity, 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.

The first step was to develop different microstructures to achieve the oleophobic effect in the client’s plastic. We then microstructured the negative of these microstructures in the injection molds, and through a simple injection process, we were able to transfer the microstructures to the parts during their manufacturing.

For characterization, we use a contact angle equipment. With it we were able to measure the contact angle of the different microstructures designed with the oils that caused the problem, obtaining an increase in the contact angle of 40º.

Finally, with the microstructure that had presented the best properties, we carried out the microstructuring of a larger mold, in order to have pieces with which to carry out the oil absorption tests and check the real functionality.