← Back to Patent Explorer
US4914266A Expired / Lapsed US ⏱️ 0.0 years remaining

Press applied susceptor for controlled microwave heating

Assignee: WESTVACO Corp 299 PARK AVENUE NEW YORK NY 10171 A CORP OF
•
Filing: 1989-03-22
•
Granted: 1990-04-03
•
Expires: 2009-03-22
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Paperboard packaging material is disclosed for use in the manufacture of cartons for heating and browning food in a microwave oven. In accordance with the present invention, a pattern of microwave susceptor is printed on paperboard packaging material using a susceptor-ink composition in the areas where the food is to be browned. The susceptor-ink composition comprises an ink vehicle into which there is incorporated a conductive carbon material such as graphite or carbon black as the susceptor material. The preferred printing process is by gravure, and the printed susceptor is overcoated with an FDA approved food contacting coating.

Inventors

  • 👤 Christopher J. Parks
  • 👤 Kenneth J. Wolfe

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 08:42
CPC Classifications
B; B65; B65D; B65D81/00; B65D81/34; B65D81/3446; B65D2581/00; B65D2581/34; B65D2581/3437; B65D2581/3463; B65D2581/3464; B65D2581/3471; B65D2581/3483; B65D2581/3486; B65D2581/3494; Y; Y10; Y10S; Y10S99/00; Y10S99/14; Y10T; Y10T428/00; Y10T428/13; Y10T428/1303

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 221 words
The method of making susceptor packaging material on a printing press for use in the manufacture of packages for microwave ovens comprising: (a) selecting a dielectric substrate for the susceptor packaging material having a food contact surface and an outer surface which will permit the passage of microwave energy therethrough; (b) preparing a susceptor-ink composition for printing on the food contact surface of the susceptor packaging material comprising on ink vehicle consisting essentially of resins selected from the group consisting of cellulose nitrate, cellulose acetate, methyl cellulose, ethyl cellulose and cellulose acetate butyrate and solvents selected from the group consisting of ethyl alcohol, allyl, amyl, benzyl, butyl, cetyl, isobutyl, ispropyl and propyl alcohol into which there is incorporated a conductive carbon material; (c) printing the susceptor-ink composition of step (b) onto the food contact surface of the dielectric substrate on a printing press, in a preselected pattern corresponding to the location of food place in packages made from the susceptor packaging material; (d) overcoating the susceptor-ink printed food contact surface of the susceptor packaging material with a food contacting coating to provide a food contact surface for food packaged in said packaging material; and, (e) further printing the outer surface of said susceptor packaging material with graphics to describe the food placed in the packages made form the susceptor packaging material.
Claim 2
Independent Claim 221 words
The method of making susceptor packaging material on a printing press for use in the manufacture of packages for microwave ovens comprising: (a) selecting a dielectric substrate for the susceptor packaging material having a food contact surface and an outer surface which will permit the passage of microwave energy therethrough; (b) preparing a susceptor-ink composition for printing on the food contact surface of the susceptor packaging material comprising on ink vehicle consisting essentially of resins selected from the group consisting of cellulose nitrate, cellulose acetate, methyl cellulose, ethyl cellulose and cellulose acetate butyrate and solvents selected from the group consisting of ethyl alcohol, allyl, amyl, benzyl, butyl, cetyl, isobutyl, ispropyl and propyl alcohol into which there is incorporated a conductive carbon material; (c) printing the susceptor-ink composition of step (b) onto the food contact surface of the dielectric substrate on a printing press, in a preselected pattern corresponding to the location of food place in packages made from the susceptor packaging material; (d) overcoating the susceptor-ink printed food contact surface of the susceptor packaging material with a food contacting coating to provide a food contact surface for food packaged in said packaging material; and, (e) further printing the outer surface of said susceptor packaging material with graphics to describe the food placed in the packages made form the susceptor packaging material.
Claim 3
Dependent Claim 14 words
The method of claim 1 wherein the printing process is a gravure printing process.
Claim 4
Dependent Claim 11 words
The method of claim 2 wherein the dielectric substrate is paperboard.
Claim 5
Dependent Claim 19 words
The method of claim 3 wherein the dielectric substrate is precoated on its outer surface with a clay coating.
Claim 6
Dependent Claim 20 words
The method of claim 4 wherein the susceptorink printed surface of the dielectric substrate is precoated with a polymeric coating.
Claim 7
Dependent Claim 31 words
The method of claim 2 wherein the susceptor-ink composition is applied to the dielectric substrate to provide a surface resistivity of from about 50-5000 ohms per square within the preselected pattern.
Claim 8
Dependent Claim 34 words
The method of claim 6 wherein the concentration of conductive carbon material in the susceptor-ink composition comprises from about 9% to 29% by weight of the susceptor-ink composition to achieve the desired surface resistivity.
Claim 9
Dependent Claim 25 words
The method of claim 6 wherein the thickness of the susceptor-ink composition applied to the dielectric substrate is varied to achieve the desired surface resistivity.
Claim 10
Dependent Claim 20 words
The method of claim 8 wherein the surface resistivity is varied within the preselected pattern printed on the dielectric substrate.
Claim 11
Dependent Claim 117 words
A printed food container for use in a microwave oven prepared from susceptor packaging material comprising: (a) a container body formed from a dielectric substrate having a solvent based susceptor-ink composition printed on the food contact surface thereof in a preselected pattern corresponding to the location of food placed in the container, said susceptor-ink composition containing conductive carbon particles suspended in a mixture of resins and solvents comprising polymeric cellulosic resins soluble in alcohol, to provide a surface resistivity within the preselected printed area in the range of from about 50-5000 ohms per square; and, (b) a barrier coating applied over the printed susceptor-ink composition to provide a food contact surface for food packaged in the container.
Claim 12
Dependent Claim 117 words
A printed food container for use in a microwave oven prepared from susceptor packaging material comprising: (a) a container body formed from a dielectric substrate having a solvent based susceptor-ink composition printed on the food contact surface thereof in a preselected pattern corresponding to the location of food placed in the container, said susceptor-ink composition containing conductive carbon particles suspended in a mixture of resins and solvents comprising polymeric cellulosic resins soluble in alcohol, to provide a surface resistivity within the preselected printed area in the range of from about 50-5000 ohms per square; and, (b) a barrier coating applied over the printed susceptor-ink composition to provide a food contact surface for food packaged in the container.
Claim 13
Dependent Claim 27 words
A printed, ovenable food container according to claim 10 wherein the thickness of the susceptor-ink composition is varied within the preselected pattern printed on the dielectric substrate.
Claim 14
Dependent Claim 32 words
A printed, ovenable food container according to claim 10 wherein the concentration of the conductive carbon particles in the susceptor-ink composition is varied within the preselected pattern printed on the dielectric substrate.
Claim 15
Dependent Claim 19 words
A printed, ovenable food container according to claim 12 comprising a fully gusseted, flanged tray having multiple food compartments.
Claim 16
Dependent Claim 20 words
A printed, ovenable food container according to claim 12 comprising a fully gusseted, flanged tray having a single food compartment.

References Cited (Backward Citations)

US2014760A Cited
US4190757A Cited
US4267420A Cited
US4230924A Cited
US4641005A Cited
US4434197A Cited
US4518651A Cited
US4595611A Cited
US4676857A Cited
US4777053A Cited
EP0276654A1 Cited
US4801774A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-04-02 1993-10-02 1994-04-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-04-02 1997-10-02 1998-04-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-04-02 2001-10-02 2002-04-03 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag