Plastic framework esp. a car radiator grille - comprises a grating surrounded by a frame consisting of a plastic skin enclosing a plastic core with a lower mould shrinkage factor

摘要

A plastic framework (I) comprises (A) a grating section, surrounded by (B) a frame with a sandwich construction consisting of (B1) an outer layer of skin-forming plastic (II) and (B2) a core of core-forming plastic (III) with a mould shrinkage factor (MSF) lower than that of (II). Pref., (III) is made of acrylic-styrene resin, ABS resin, rigid PVC, polybutylene terephthalate (PBT) or polypropylene (PP), and contains an inorganic filler (pref. glass fibre and/or talcum) and pref. a blowing agent; (III) has MSF 10-50% below that of (II), and is pref. harder than (II). (II) is made of ABS resin, acrylonitrile-acrylate rubber-styrene resin or flexible PVC. USE/ADVANTAGE - Used esp. as a car radiator grille. The invention provides a plastic framework which enables the use of a mould of simple construction (contrast prior-art grills, which require a complicated mould or several different moulds). The framework has excellent mechanical strength, e.g. rigidity, and is resistant to deformation due to the differences in MSF of the components (this difference can cause buckling in the thinner grating section).