Molded circuits

Moldings. coatings, membranes rigid, transparent. self-e>ctinguishing, resistant to heat deformation used for electrical components, molded circuit boards, appliances operating t high temperatures, e.g., VIctrex PES. 

As a manufacturing technology, selective metallization of a molded plastic substrate has wide utility in electrical and electronic componentry, connector and receptacle devices, customized IC carriers, electro-mechanical and electro-optical products. "The major benefits which come from a molded circuit board may be grouped under four headings including structural/mechanical, material, cost and design/aesthetics. 

The materials shown in Table I are available in varying molecular weights and filler compositions. For molded circuit applications, the most commonly used fillers comprise chopped or milled glass fibers and/or mineral talcs. In addition to these fillers, additional components may be incorporated to impart flammability resistance or to promote electroless plating. The latter is achieved by the addition of a proprietary mineral filler which renders the polymer "catalytic" to plating. 

The unique attributes of "catalyzed resins are that they eliminate the need for secondary (after molding) pre-plate activation or "seeding" operations common to conventional plating-on-plastics (POP) processes. For molded circuit board manufacture, catalytic resins are used in two-shot (two-component) molding processes which form highly complex 3D plastic structures which are capable of being selectively plated without the need for plating masks or resists. Polymers currently available in a "catalytic" composition include only amorphous sulfone and imide based systems. 

The creation of molded circuit boards which reduce "down stream" assembly costs. 

The bringing together of 3-dimensional molding skills and interconnection systems to create components which do two jobs in one, acting as a case, cover or some kind of housing, at the same time doubling as a molded circuit boards." (8)... 

BPA (Technology Management. Ltd.) Technology Update Molded Circuit Boards Surrey, U.K., 1988, p 1. 8705,... 

Although some substrates may be molded plastic (3-D or molded circuits) or flexible film plastic materials (flexible circuits), the largest group of substrates is of rigid laminate construction. The laminate construction consists of many layers of resin-treated fibers, fabrics, or papers, which are called reinforcements. 

A handful of three-dimensional molded circuit manufacturers (or, the preferred identification, molded interconnection device or MID) have continued their quest for market with this... 

FIGURE 31.8 An example of a three-dimensional molded circuit application, in this case a light pen for computer input. (Photo courtesy of Mitsui Pathtek.)... 

Examples of molding circuits and automation circuits Mold Desi0n and Maintenance for Dia fnostics (20 hour Module) Design considerations Mold design basics Cavity and core construction Heat transfer considerations Cold runner molds Hot runner systems Freeing mechanism/part ejection Mold maintenance... 

Materials, Manufacturing, Assembly, and Applications for Injection Molded Circuit Carriers... 

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