Abstract: A method for making a patterned metal foil/substrate laminate by laminating a sheet of metal foil to a substrate by applying an adhesive between the metal foil and substrate and irradiating the metal foil with a laser beam in a predetermined pattern to vaporize the irradiated portions of the metal foil. Particularly where the laminate is intended for microwave packaging applications, the laminate further includes a sheet of barrier layer material, preferably polymer film, laminated to the patterned metal foil layer. The polymer film layer-containing laminate can be formed into a container for packaging food intended for heating in a microwave oven. A particularly effective pattern comprises a plurality of metal foil islands electrically separated by dielectric substrate gaps. Preferably, the metal foil is aluminum foil, desirably unannealed aluminum foil, and the substrate is selected from paper and coated or uncoated paperboard.

Abstract: An RF EAS tag includes a substrate with a conductive element positioned on a face surface thereof and having electrically inductive properties. A capacitive element is positioned on the face surface and has electrically capacitive properties wherein the inductive and capacitive elements are operably coupled together to form a resonant circuit which resonates when an electrical signal of a predetermined resonant frequency is applied to the tag. The capacitive element comprises a dielectric ink substance having a high dielectric constant for producing the desired resonant circuit on a single face surface of the substrate. An alternative tag comprises a substrate with a conductive layer positioned thereon and a gap formed in the conductive layer exposing a portion of the substrate. This forms a slotline waveguide shorted at both ends. A high dielectric constant ink substance is then deposited in the slot.

Abstract: A patterned metal foil/substrate laminate wherein the pattern is formed by laminating a sheet of metal foil to a substrate by applying an adhesive between the metal foil and substrate in a predetermined pattern which defines areas where adhesive is present and areas where no adhesive is present, cutting the metal foil, as by rotary die cutting or laser cutting, in a pattern which corresponds to the boundaries of the adhesive-containing areas and removing the areas of metal foil which are not adhesively adhered to the substrate. Particularly where the laminate is intended for microwave packaging, the laminate further includes a sheet of barrier layer material, preferably polymer film, laminated to the patterned metal foil layer.

Abstract: A food package including a package body forming a food receiving cavity for storing and heating a food item in a microwave oven. Specifically, the package body includes a bottom panel and a top panel with side panels joining the bottom and top panel. An impedance matching element is provided on at least one of the panels for impedance matching microwave energy entering the package. The impedance matching element is preferably a contiguous film of thinly flaked material embedded in a dielectric binder which is sized and shaped with respect to the food to cause impedance matching to elevate the temperature of the food in predetermined areas dependent upon the size and spacing of the film without interacting with the microwave energy to produce heat. The film may also be shaped in the form of a convex lens to direct impedance matched microwave energy toward the food to elevate the temperature of the food in a predetermined area.

Abstract: A self-limiting dispersion of a conductive material in a binder is disclosed wherein the conductive material consists essentially of a carbon material having a structure selected to undergo percolation when dispersed in the binder at a concentration of from about 10 weight percent to about 45 weight percent. The binder comprises a thermoplastic material selected to go through a first order phase transition or a second order transition at a temperature from about 300.degree. F. to about 480.degree. F. and the dispersion is formulated near the conductance percolation threshold so that its electrical conductivity drops precipitously (e.g., at least about 1.5 orders of magnitude) above the binder transition temperature. The dispersion of the conductive material in the binder is especially suitable for use as a self-limiting microwave heater material which is either a molding composition, or surface coating composition, and especially a composition that can be applied to a substrate by printing.

Abstract: Microwave interactive coating compositions are disclosed which comprise finely divided carbon, a powdered inert solid and a binder. A preferred composition comprises finely divided carbon, finely divided microwave reactive metal, powdered inert material and a dielectric binder, preferably an acrylic latex. These compositions are capable of producing microwave reactive heaters comparable to those produced by vapor deposition of metals on a carrier film.

Abstract: A microwave interactive coating composition and microwave reactive paper and paperboard heaters comprising the coating composition are disclosed. The coating compositions which comprise finely divided carbon, a finely divided microwave reactive metallic component, a powdered inert solid and a binder are capable of producing microwave reactive heaters comparable to those produced by vapor deposition of metals on a carrier film.

Abstract: Microwave responsive heaters and packages for food products and the like containing the heaters are disclosed in which the heaters consist of a microwave reactive coating composition on a heat stable substrate which is pattern bonded to a surface to be heated by microwave radiation.

Abstract: An ink jet printing substrate particularly useful as a coating for paper for multi-color, water base ink jet printing consisting essentially of a high swelling montmorillonite clay, and optionally including a high surface area pigment, such as a synthetic silica or calcium carbonate and a water-insoluble binder.