Importance

Loading Importance Indicators...

Abstract

There is disclosed a method of operating an injection-molding machine to produce a composite item that includes a portion of soft material such as a set of bristles tending to cling to a mold cavity in which it is formed. At a first station, a relatively flexible plastic material is injected into a first cavity shaped to define the portion of soft material of the composite item, that portion including a backing layer. The portion of soft material is then allowed to cool, and at a subsequent station there is injected a relatively rigid plastic material into a second cavity bounded by the backing layer. The second cavity defines a harder portion of the composite item such as a brush handle. After the latter portion has also cooled, the portion of soft material is separated from the first cavity by pulling on the harder portion at a rate of speed slow enough to avoid rupture of the portion of soft material.

Loading the Abstract Image...

First Claim