Abstract: A tape ball grid array package reverses the usual attachment of flexible circuitry to a stiffener so that the circuit traces face the stiffener rather than away from the stiffener as is conventional. This construction allows the elimination of a previously necessary solder mask and so reduces the cost to produce the package.

Abstract: A hot roll, for use in a xerographic hot roll fuser, is made by coating a hollow aluminum cylinder with an elastomer, as by the use of an injection molding machine. After molding, the external surface of the elastomer cylinder is ground slightly to improve its concentricity. Thereafter, this ground external surface is subjected to the chemical influence of an acid. After a predetermined time period, the acid treatment is terminated and the roll is washed in water. The resulting hot roll, whose external surface has been chemically modified, possesses improved dry-release properties.

Abstract: A hot roll, for use in a xerographic, dry-release, hot roll fuser, is made by a method which adds iron-containing, magnetically permeable, particles to the elastomer as the elastomer is mixed. The particles may be pre-coated with a silane adhesive promoter. The mixed elastomer is then injected around a hollow, cylindrical aluminum core. As the elastomer sets up, in the mold, a magnetic field is applied such that the iron-containing particles migrate toward the metal core, and away from the exterior surface of the elastomer. This exterior surface will later be used to fuse xerographic toner. After the elastomer has set, its external surface is ground slightly, to produce a true circular-cylinder, but without exposing the underlying, more dense, layers of iron particle filler. As a result, the elastomer-to-core interface is mechanically strong, and yet the fusing property of the elastomer is not degraded by the presence of filler.