Packs: laminated board

Laminate board packs are made either from flat reels of material or from preformed blanks. These systems are generally tied , that is, the laminate supplier also makes the filling equipment. The fillers are well proven microbiologically and do not need to be placed within a special environment. 

Multilayer boards, which use multiple interior laminates of plastic and copper, now comprise over half of the value of production, though much less on a surface area basis. Surface mount technologies demand extreme flatness and reproducibiHty from surfaces. Greater packing density has led to commercial production of finer lines and holes, often less than 50 p.m and 500 p.m, respectively. Electroless gold over electroless nickel—phosphoms, or electroless nickel—boron alone, is often used as a topcoating for wire bonding or improved solderabiHty. 

The long-shelf-life packs for aseptic products are often made of a board, foil, plastic (polyethylene) laminate which gives protection from oxygen ingress and... 

In the flat as sheets or reels, e.g. paper, board, tinplate, films, foils and laminates. Materials in both sheet and reel forms may be further processed to give packs which may remain in the flat (e.g. collapsible cartons) until erected or are directly fabricated into a three-dimensional container (tinplate containers, composite drums, rigid boxes, etc.). Distortion printing also falls into this category. 

MAJOR APPLICATIONS Printed circuit boards, laminating powder, carbon-fiber composites for aero-engines and military aircraft parts such as flap inboard cover, forward nozzle, gun pack, ammunition pack, blade choke, deep choke, speed brake, and ventral fin/ ... 

The adoption of double-sided, copper clad laminates together with plated-through-holes permits a much higher packing density of components. A circuit pattern is produced via etching on both sides of the board followed by interconnection of the two sides via plated-through-hole fabrication. 

Substrates made by the multilayer process from tape cast alumina have received considerable attention in recent years for multichip module (MCM) applications. An MCM consists of an array of closely packed chips on an interconnect board several inches on a side. Cofired ceramic is attractive relative to organic laminates because its thermal conductivity is almost 2 orders of magnitude higher, an important consideration in high-density circuitry. In addition both alumina and aluminum nitride ceramics are more closely matched to silicon in CTE than are organic boards. For similar reasons, alumina and AIN are attractive for ball grid array (EGA) mounting of chips. ... 

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