Thermoforming: IMD parts with textile surfaces, no glue

A German processor claims a novelty with its process for first thermoforming the semifinished textile-covered parts, and then back injection molding these for use as armrests, headliners, or other parts, all likely to see use first in automotive applications. The fabric is laminated to its backing film in the thermoforming tool and with no need for adhesives.

Officials at Reiss Kunststofftechnik GmbH (Tettnang, Germany) say the process is particularly suitable for processing of high-end parts with surfaces of textiles, foam, or fleece. Parts can be formed with textile covering their entire surface or with only partial covering. Parts’ geometry/complexity is said not to hinder the process.

Direct lamination of the textile to a backing film is done in the tool as the film is thermoformed. After this, the semifinished parts are punched and trimmed, and then ready for use in inmold decoration. Reiss automates the handling, forming, and binding of the textile to the plastic sheet during thermoforming; it says this brings both economic and quality (haptic) advantages to other direct lamination procedures.

Reiss has been processing the laminated thermoformed parts for some years but only struck gold with use of these in inmold decoration late last year, when the process was first used commercially for an automotive part.

The processor also has further developed the process for realizing a metal surface finish on insert molded parts. New is that customers requiring a small-to-medium-sized order of parts can ask for enhancement of the insert film via an individual silk screening of the extruded film. The printed films are then suitable for thermoforming and can be back injection molded. With use of a transparent film, the printed design can be protected and, because it is on the back of the film, offers depth to the appearance of a part. —Matt Defosse