Abstract: Extrusion-to-sheet production line and method comprise first and second rolls set to a predetermined gap through which a continuously-extruded sheet of molten plastic material passes to calender the sheet to a predetermined thickness. The sheet passes through a nip formed between the second roll and a continuous belt looped around a third roll and a fourth roll. The belt comprises an embossing pattern of optical element shapes that is an inverse pattern of optical element shapes to be embossed at a first major surface of the sheet. The sheet remains in contact with the second roll until the sheet passes through the nip, where the pattern of optical element shapes on the belt is embossed into the first major surfaces of the sheet. Downstream of the third roll is a cooling area through which the belt passes.

Abstract: Extrusion-to-sheet production line and method comprise first and second rolls set to a predetermined gap through which a continuously-extruded sheet of molten plastic material passes to calender the sheet to a predetermined thickness. The sheet passes through a nip formed between the second roll and a continuous belt looped around a third roll and a fourth roll. The belt comprises an embossing pattern of optical element shapes that is an inverse pattern of optical element shapes to be embossed at a first major surface of the sheet. The sheet remains in contact with the second roll until the sheet passes through the nip, where the pattern of optical element shapes on the belt is embossed into the first major surfaces of the sheet. Downstream of the third roll is a cooling area through which the belt passes.

Abstract: Extrusion-to-sheet production line and method comprise first and second rolls set to a predetermined gap through which a continuously-extruded sheet of molten plastic material passes to calender the sheet to a predetermined thickness. The sheet passes through a nip formed between the second roll and a continuous belt looped around a third roll and a fourth roll. The belt comprises an embossing pattern of optical element shapes that is an inverse pattern of optical element shapes to be embossed at a first major surface of the sheet. The sheet remains in contact with the second roll until the sheet passes through the nip, where the pattern of optical element shapes on the belt is embossed into the first major surfaces of the sheet. Downstream of the third roll is a cooling area through which the belt passes.

Abstract: Extrusion-to-sheet production line and method comprise first and second rolls set to a predetermined gap through which a continuously-extruded sheet of molten plastic material passes to calender the sheet to a predetermined thickness. The sheet then passes through a nip formed between the second roll and a continuous belt looped around a third roll and a fourth roll spaced from one another. The belt comprises an embossing pattern of optical element shapes that is an inverse pattern of optical element shapes to be embossed at a first major surface of the sheet. The sheet remains in contact with the second roll until the sheet passes through the nip, where the pattern of optical element shapes on the belt is embossed into the first major surfaces of the sheet. Downstream of the third roll is a flat cooling area through which the belt passes while the first major surface of the sheet is still in contact with the embossing pattern on the belt.

Abstract: A process and apparatus for embossing thermoplastic products having precise microstructured surfaces including using a continuous press having upper and lower belts with the embossing pattern(s); feeding thermoplastic material through the press where heat and pressure are applied to form the embossed pressure microstructure, and cooling the embossed material, all while maintaining pressure. A continuous embossing tool is provided by welding segments together, the welds including interface material at the weld joint which is of a different material than the segment material to increase the tensile strength.

Abstract: A sheet (20) for use in microfluidic, microelectronic, micromechanical, and/or microoptical applications requiring through-flow, through-conductivity, through-transmission, and/or other through patterns. The sheet (20) includes micro-sized architecture including at least one via (22) extending through the thickness of the layer of thermoplastic material. The via-defining walls in the thermoplastic layer are formed by the thermoplastic material flowing around a projection and then solidifying around the projection.

Abstract: A substrate having embossed thereon a plurality of shaped recesses of a predetermined precise geometric profile, each recess having a flat bottom surface having a major dimension of about 500 &mgr;m or less, the substrate being capable of undergoing a thermal cycle of about one hour at about 150° C. while maintaining about ±10 &mgr;m or less dimensional stability of the embossed shaped indentations, and wherein the substrate comprises an amorphous thermoplastic material. During the thermal cycle the substrate has an elastic modulus greater than about 1010 dynes/cm2 and a viscoelastic index of less than about 0.1.

Abstract: Cellular retroreflective sheeting comprises a first film of thermoplastic material which has been formed to define arrays of minute cube-corner reflective elements on one face thereof. The reflective elements are covered with a second thin thermoplastic film and the two films together pass over a patterned roller where a series of sonic welding heads rapidly bond the films together forming small cells of retroreflective cube-corner elements in the pattern of the roller. Because the heat generated in the welding process is localized to the pattern of the roller, cell walls may be formed having narrow thickness yet good bonding of the films is achieved. Further, residual heat does not appreciably transfer to adjacent retroreflective elements, therefore, distortion of adjacent elements is minimized and a sheeting construction is achieved having superior brilliance and durability as well as maximum retroreflective capability over a wide angular range of incident light.

Abstract: A process and apparatus for manufacturing fuel cell plates are disclosed, the apparatus including a continuous press, a sifter, a leveler and rollers for removing air from resin impregnated graphite. An electrostatically charging device and a vibratory dispensing device may also be used. The sifted material is deposited on a heated lower press belt which is the belt having an embossing pattern. The material is leveled to a predetermined height and squeezed to remove air. An upper belt, also having an embossing pattern, contacts the material and heat and pressure are applied in a reaction zone for a predetermined time period. The process may also include the making of a tool integral with one or both belts for embossing the fuel cell plates. The finished product is a relatively low cost fuel cell plate.

Abstract: A process and apparatus for embossing thermoplastic products having precise microstructured surfaces including using a continuous press having upper and lower belts with the embossing pattern(s); feeding thermoplastic material through the press where heat and pressure are applied to form the embossed pressure microstructure, and cooling the embossed material, all while maintaining pressure. A continuous embossing tool is provided by welding segments together, the welds including interface material at the weld joint which is of a different material than the segment material to increase the tensile strength.

Abstract: A substrate having embossed thereon a plurality of shaped recesses of a predetermined precise geometric profile, each recess having a flat bottom surface having a major dimension of about 500 &mgr;m or less, the substrate being capable of undergoing a thermal cycle of about one hour at about 150 ° C. while maintaining about ±10 &mgr;m or less dimensional stability of the embossed shaped indentations, and wherein the substrate comprises an amorphous thermoplastic material. During the thermal cycle the substrate has an elastic modulus greater than about 1010 dynes/cm2 and a viscoelastic index of less than about 0.1.

Abstract: A process for manufacturing fuel cell plates including a continuous press, a sifter, a leveler and rollers for removing air from resin impregnated graphite. The sifted material is deposited on a heated lower press belt having an embossing pattern. The material is leveled to a predetermined height and squeezed to remove air. An upper belt, also having an embossing pattern, contacts the material and heat and pressure are applied in a reaction zone for a predetermined time period. The finished product is a relatively low cost fuel cell plate.

Abstract: An apparatus for manufacturing fuel cell plates including a continuous press, a vibrating hopper, a leveler and rollers for removing air from resin impregnated graphite. The sifted material is deposited on a heated lower press belt which is electrostatically charged, the belt having an embossing pattern. The material is leveled to a predetermined height and squeezed to remove air. An upper belt, also having an embossing pattern, contacts the material and heat and pressure are applied in a reaction zone for a predetermined time period. The finished product is a relatively low cost fuel cell plate.

Abstract: An apparatus for manufacturing fuel cell plates including a continuous press, an electrostatically charging element, a sifter, a leveler and rollers for removing air from resin impregnated graphite. The sifted material is deposited on a heated lower press belt which is electrostatically charged, the belt having an embossing pattern. The material is leveled to a predetermined height and squeezed to remove air. An upper belt, also having an embossing pattern, contacts the material and heat and pressure are applied in a reaction zone for a predetermined time period. The finished product is a relatively low cost fuel cell plate.

Abstract: Cellular retroreflective sheeting comprises a first film of thermoplastic material which has been formed to define arrays of minute cube-corner reflective elements on one face thereof. The reflective elements are covered with a second thin thermoplastic film and the two films together pass over a patterned roller where a series of sonic welding heads rapidly bond the films together forming small cells of retroreflective cube-corner elements in the pattern of the roller. Because the heat generated in the welding process is localized to the pattern of the roller, cell walls may be formed having narrow thickness yet good bonding of the films is achieved. Further, residual heat does not appreciably transfer to adjacent retroreflective elements, therefore, distortion of adjacent elements is minimized and a sheeting construction is achieved having superior brilliance and durability as well as maximum retroreflective capability over a wide angular range of incident light.