Abstract:
The object of the present invention is to provide a metal-clad phenolic resin laminate having a combination of machine properties, electrical properties and tracking resistance. A metal-clad phenolic resin laminate obtained by heating and pressing a lamination which comprises: (i) a central layered portion comprising one paper base prepreg which is made of a paper base impregnated with a first phenolic resin composition containing a resol-based resin, or a predetermined number of the paper base prepregs laid on each other; (ii) outer layered portions laid on an upper and a lower sides of the central layered portion, in which each of the outer layered portions comprises one glass fiber substrate prepreg which is made of a glass fiber substrate impregnated with a second phenolic resin composition containing a resol-based resin, or a predetermined number of the glass fiber substrate prepregs laid on each other; and (iii) a metal foil laid at least on one of the outer layered portions laid on the upper and lower sides of the central layered portion.
Abstract:
A compressible interposer comprising an interposer sheet having a plurality of apertures filled with a dielectric material having a substantially uniform suspension of conductive particles therein forming a plurality of conductive sites. Preferably, the number of conductive sites on the interposer are greater in number than the number of contact pads on the electronic components such that precise alignment of the interposer between the electronic components is not required. The apertures of the interposer sheet confine the conductive particles within the dielectric material such that during compression of the interposer between the electronic components, z-axis conductive pathways are formed without shorting in the x and y directions. Preferably, the interposer sheet comprises polyimide. Preferably, the dielectric material comprises polyimide-siloxane. Preferably, the conductive particles have a diameter of about 2 to about 20 &mgr;m and comprise of a material selected from the group consisting of copper, gold, silver, nickel, palladium, platinum, and alloys thereof. The particles may also be coated with an additional conductive material such as solder having a lower melting temperature. Most preferably, the conductive particles comprise solder coated copper particles. The conductive particles are present in an amount of about 30 to about 90 wt. % of the total weight of the conductive particles and the dielectric material.
Abstract:
Resin compositions for laminated sheets and laminated sheets produced therefrom are disclosed, the compositions comprising at least one allyl ester resin composed of a polybasic acid and a polyhydric alcohol, wherein an allyl ester group of said resin is bonded to at least one of terminals thereof.
Abstract:
A transfer for use with automatic offset application equipment comprises a backing paper, release layer, design layer and covercoat layer, in which the covercoat layer is formed from a heat-activatable adhesive and extends over an area greater than that of the design layer. Preferably the design layer also has heat-activatable adhesive properties. Such transfers are especially for use with enamel printing inks for the decoration of ceramic ware. In use, a heated platen is used to melt the release layer and a heated pressure pad is brought into contact with the transfer to activate the adhesive and effect the transferring operation.
Abstract:
Method of printed circuit board manufacture, and resulting board. A plurality of prepreg sheets composed of ceramic paper and containing different quantities of a resin are laid on each side of a core metal sheet having a through hole. A copper foil is laid on the prepreg sheets on each side of the core. All of the layers are pressed together under heat to make a metal-core printed wiring board. The prepreg sheets form an insulating layer having a high heat-dissipating capacity on each side of the core and a reliable insulator in its through hole. The ceramic paper consists essentially of short ceramic fibers having a diameter not exceeding fiber microns and a length of 5 to 500 microns, and contains 3 to 10% by weight of microfibrillated cellulose fibers as a binder for the ceramic fibers.
Abstract:
Substrate composites, well adopted for the production of metallized printed circuits and facilely prepared by, e.g., papermaking procedures, include a central core layer comprising fibrous cellulosic material or flaked mica within a matrix of a thermosetting resin binder, said central core element having coextensively laminated to at least one of the face surfaces thereof, a lamina of a thermosetting resin comprising non-conductive metal oxide filler material distributed therethrough, and said metal oxide being borohydride reduceable and reactive to form unstable metal hydride intermediates.
Abstract:
A continuous process for producing reinforced resin laminates comprising the steps of impregnating a fibrous substrate with a liquid resin which is free of volatile solvent and is capable of curing without generating liquid and gaseous byproducts, laminating a plurality of the resin-impregnated substrates into a unitary member, sandwiching the laminate between a pair of covering sheets, and curing the laminate between said pair of covering sheets without applying appreciable pressure. The improvement comprises adjusting the final resin content in said resin impregnated substrate at 10 to 90% by weight based on the total weight of said impregnated substrate.
Abstract:
A continuous process for producing reinforced resin laminates comprising the steps of impregnating a fibrous substrate with a liquid resin which is free of volatile solvent and is capable of curing without generating liquid and gaseous byproducts, laminating a plurality of the resin-impregnated substrates into a unitary member, sandwiching the laminate between a pair of covering sheets, and curing the laminate between said pair of covering sheets without applying appreciable pressure. The improvement comprises adjusting the final resin content in said resin impregnated substrate at 10 to 90% by weight based on the total weight of said impregnated substrate.
Abstract:
This invention relates to insulating laminates which consists with several sheets of reinforcements (1) inpregnated with curable resin and layers (2) of cured resin located between each reinforcement. Metal clad laminates is also disclosed which is consisting with reinforcement (1), layers (2) of cured resin and metal foil (5) to be placed on the laminates. Each reinforcements (1) are substantially isolated by the resin layers (2).
Abstract:
An entry material for use in drilling circuit boards to avoid marring of such boards comprises a wood pulp-glass composite substrate having aluminum foil bonded to the opposite surfaces thereof. This entry material is relatively economical and has a stiffness sufficient to avoid upward bending or "oil canning" when pressure feet spaced from the drill are employed to hold the workpiece during drilling and further has enough strength to withstand high torsional drill forces with drills operating for high rates of material removal. The double layers of foil separated by the low heat conductive substrate material affords a pair of heat sinks which more effectively can carry away heat from the drill.