Long fibre technology for door skins
The manufacturer of windows and doors, Jeld-Wen, Klamath Falls, Oregon, USA, has introduced a new exterior door line to its portfolio this July: Jeld-Wen premium fibreglass doors with PU fibre technology. The skins of these doors are moulded from a customised formulation of polyurethane materials from Bayer MaterialScience LLC, Pittsburgh, USA. Together with its customer, the researchers of Bayer Material- Science have developed a formulation from Baytec SPR spray polyurethane and Baydur STR polyurethane specifically for this application. According to BMS, use of these materials gives the doors increased dimensional stability, better impact resistance and strength, along with the excellent aesthetics demanded by consum. The skins are formed using long fibre technology, in which long glass fibres are injected along with PU resin in a one-step process. Then the composite door skins are laminated to a polystyrene core and wood edge frame. The benefits of long fibre technology include:
- Ability to utilize lower-cost fibreglass rovings rather than mats, which also reduces troublesome worker handling of the mats;
- Ability to vary the amount of fibreglass reinforcement in the part to focus high strength where it is most needed;
- Ability to use either a foamed or solid PU formulation,
- Ability to produce parts with PU in-mold coating, thus eliminating secondary painting operations.