Over-molding

Over-molding Over-molding is also called in-mold assembly, two-color rotary, or two-color shuttle. Two materials are molded so that the first molded shot is over-molded by the second molded shot first molded part is positioned so the second material can be molded around, over, sections, or through it. The two materials can be the same or different and they can be molded to bond together or not bond together. If materials... 

Certain applications of over-molding are not restricted to a low pressure. Two-shot... 

Recently, there has been considerable interest in soft-touch materials composed of thermoplastic and mbber blends. These materials when over-molded on hard or stiff stmctures such as hand tools, domestic appliances, writing gadgets, cellular phones, photographic equipments, etc. provide soft and comfortable feeling to the hand. 

Portions of the sun visor arms used in automobiles can be manufactured from glass-filled thermoplastic polymers. Several visor arms contained visible blemishes on the surface. Typically, the steel insert of the visor arm is overmolded with the glass-filled thermoplastic polymer. Manufacturers sometimes utilize striations on the steel insert to provide a mechanical interlock with the over-molded thermoplastic polymer. However, in an improperly controlled environment, the mechanical process that produces the striations can also be the source of contamination and cause surface blemishes in the final product. 

Pour PDMS to desired thickness over mold. Degas PDMS to remove any air bubbles. 

FIGURE 2.40 Pressure forming (a) heated sheet is clamped over mold cavity (h) compressed air pressure forces the sheet into the mold. 

Rigid laminate substrate (with or without soldermask), wire bonds, over-molded... 

Conductive adhesives also form sufficiently robust joints that withstand the temperatures and pressures experienced during wirebonding and over molding. The formulation of die attach materials is discussed in Section IV. 

Satin weave The warp and weft threads are crossed in a programmed order and frequency to obtain a flat appearance. As a result, one side of the fabric has more warp threads, while the back appears to consist mainly of weft threads. The higher the satin number (7 satin, 8 satin), the higher the count of warp and weft threads. Satin weaves allow production of fabrics with high mass per unit of surface area, and good drapability over molds. Different satin patterns are used. See Ei t hamess satin and four-harness satin. 

Hybrid conversion in front-end modules has been led by Bayer, whose patented injection over-molding method has been used by Volkswagen, Audi, Nissan, and Ford since 1996. Ten new platforms, including several light trucks, are used in North America through mid-2004. Also aboard are alternative hybrid systems developed by Rhodia Engineering Polymers, Dow Automotive, and BASF Performance Polymers. 

A recent refinement is in-mold assembly of hybrids. Two or more metal stampings are robotically placed in the mold with holes aligned, and then they are over-molded into one piece with nylon. This approach will reduce the assembly costs of front ends, door modules, and window regulators. 

Copper leadframe, low-loop wire bonds or flip-chip interconnect, over-molded 50% size reduction compared to thin-shrink small-outline package (TSSOP) inductance (MicroLeadFrame ) and very low inductance flip-chip MicroLeadFrame MicroLeadFrame (wire bond) and flip-chip MicroLeadFrame (/cMLF) (Amkor) Portable electronics (cell phones and personal data assistants) (PDAs), MicroLeadFrame and high-performance applications in the 5-40 GHz range... 

Rigid laminate substrate (with or without soldermask), wire bonds, over-molded Small outline, low profile (1.0 mm), enhanced electrical performance over 2.4 GHz, JEDEC moisture sensitivity level (MSL) 3 Plastic thin fine pitch quad flat no lead package (P-TFQFN), plastic thin shrink small outline no lead package (P-TSSON), and fine-pitch BGA, FBGA (National) Portable applications, flash memory... 

Thin-core laminate, low-loop wire bond, and standard over-mold Thinnest available package (0.5 mm mounted height), and JEDEC MSL 1 Extremely thin CSP , etCSP (Amkor) EEPROM devices, PCMCIA card appHcations, and minidisk drives... 

Upilex tape, wire bonded, over-mold Near chip-scale package Economic Chip Scale Package-Tape, (EconoCSP-T, ChipPAC) DSPs, ASICs, flash memory, SRAMs, and PC chipsets... 

Polyimide tape, die and wire bond, over-mold Near CSP FBGA-T (ChipPAC) DSPs, memory products, ASICs, and SRAMs, cell phones, and pagers... 

Polyimide layer for redistribution traces, over-molded 30% reduction in board area, 65% thinner profile. Super CSP (Fujitsu) Flash memory and ASIC... 

Technologically advanced features position the 9000 full face respirator as the leader in its field. The exclusive over-molded lens design eliminates the usual heavy clamping frame to create an innovative full face with lighter weight, fewer parts, greater field of vision, minimal maintenance and completely free of metal parts. Moldex, www.moldex.com. 

Scientific research has also suggested that this inhibitory activity of LAB over molds may result from the production of metabolites such as organic acids (in particular, lactic, propionic, and acetic acids), carbon dioxide, ethanol, hydrogen peroxide, diacetyl, reuterin, and other small molecular weight metabolites production of proteinaceous compounds or low-molecular weight peptides competitive growth decrease in the pH caused by acid production or a combination of these factors (Bianchini BuUerman, 2010). 

Adhesion to inks, adhesives, and over-molding substrates... 

Polycarbonate over-molded with a carbon fiber reinforced PEEK has been used by Entegris to make linear wafer carriers for the semiconductor industry. 

A standard injection molding machine equipped with typical reciprocating screw and barrel capacity of six or less shots can be utilized for over molding. A reciprocating screw generally delivers quick color change and provides smooth TPE... 

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