Method of two shot mold metallizing of polymer components

Abstract

A component is provided that is net shape molded using a polymer to form the core structure and which includes an integrally formed metallized coating or layer on at least one of the exterior surfaces thereof. The process of forming the component includes two-shot molding process wherein a thin layer of metal or the base polymer component is molded, the mold is adjusted and then the remainder of the part is molded. Alternately, an insert molding process may be employed such that after the polymer base part is formed, it may be placed into a mold cavity that is slightly larger than the entire part, thereby allowing substantially the entire exterior surface of the part to be over molded with a molten metal.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is related to and claims priority from earlier filed U.S. Provisional Patent Application No. 60 / 672,738, filed Apr. 19, 2005, the contents of which are incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] The present invention relates generally to polymer components having a metallic coating on at least one exterior surface thereof. More specifically, the present invention relates to a molded polymer component with a metallic layer on at least one of its exterior surfaces that is entirely formed within the mold cavity before the part is removed from the mold. Further, the present invention is directed to a method of forming a molded polymer part to include a metallic layer about at least one of its exterior surfaces while the part remains in the mold [0003] In the component manufacturing industry, it is highly desirable to form components using the least amount of component handling and the fewest number ...

AI Technical Summary

Benefits of technology

"The present invention provides a method for making a net shape molded component with a metallized coating on at least one of its exterior surfaces. This is done using a polymer and a two-shot molding process where a thin layer of metal or the base polymer component is molded, the mold is adjusted, and then the remainder of the part is molded. The method allows for the formation of a highly durable and resistant to wear metallized surface without additional steps and with desirable aspects of the net shape molding process. The invention also provides a net shape molded polymer component with at least one exterior surface coated with a metallic material during the net shape molding process."

Problems solved by technology

While the net shape molding process works well for a broad range manufactured components, the difficulty with using a net shape molding process, particularly with polymer materials, is that often other steps are required in order to impart various other desirable properties to the part after the molding step is completed.

In either case, the cost of manufacturing the part is dramatically increased.

Principally, as was stated above, metallizing dramatically increases the cost and time required to manufacture the part.

These additional steps introduce a great deal of additional handling of the part before it attains its finished state and result in nearly doubling the cost associated with manufacturing the part.

Further, even though the cost of the part is increased dramatically, the coating is highly susceptible to wear, peeling, flaking and scratching, all of which lead to premature failure of the component.

While the thermal conductivity of the polymer is improved by the addition of such fillers, the cost of these conductive fillers is typically quite high and the filler loadings that are typically required in order to attain the desired thermal and electrical conductivity properties also resulted in a dramatic impact on the flexibility and strength of the base polymer resin.

This is particularly problematic when trying to increase the electrical conductivity of the part because electrical flux tends to travel over the surfaces of objects, precisely in the region of the part that has the lowest concentration of filler material.

Accordingly, it is difficult to produce a part that has a relatively high electrical conductivity using net shape molded filler polymers.

An additional difficulty arises when only a portion of the part requires a metallic surface.

As can be appreciated this introduces an additional time consuming step in the process of manufacturing the component.

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