Abstract
Stampable sheets can be made consisting of polypropylene (PP) plies and long glass fibre mat plies. Because stampable sheet is recyclable, and it shows good mechanical properties and processability, it is used for automotive products. However, products made of stampable sheet do not have sufficient surface smoothness, so they are not used for exterior parts that require high surface quality. In this study, the moulding conditions needed for good surface smoothness was investigated. The results indicated that surface smoothness is affected by mould temperature. When the mould temperature was near the melting temperature of the resin, the products had high surface smoothness, but this condition was not appropriate for mass production because it lengthened the production cycle too much Finally, we proposed suitable moulding conditions.