摘要：
A coated laminate is described comprising a microwave transparent supporting sheet or substrate (48) such as a paper, paperboard or plastic upon which is printed a susceptor lamina (50) comprising a cured dispersion of an organic printing ink vehicle matrix in which is uniformly suspended at least two kinds of dispersed particles, one of which is an electrically conductive microwave interactive carbon particle and the other of which is an electrically nonconductive suspended mineral attenuator particle for dissipating, spreading and modulating the energy received by the conductive particles. Of the two kinds of suspended particles, only the carbon particles interact with microwave energy directly. Both types of suspended particles remain dispersed in the ink vehicle until printed and cured.
权利要求：
AMENDED CLAIMS [received by the International Bureau on 12 March 1990 (12.03.90) original claims 2 and 5 cancelled- claim 1 amended;' claims 3-17 unchanged but renumbered 2-15; new claims 16-26 added (5 pages)]
1. A laminate for the microwave heating of a packaged product to be heated in a microwave oven comprising at least two supporting sheets of dielectric material, one of which serves as a susceptor substrate and a microwave susceptor composed of a microwave inductive substance containing ink layer printed onto one of the sheets over a selected portion of its surface in alignment with the packaged product to be heated, the printed susceptor layer has different zones wherein different quantities of ink cover areas of equal size in the different zones to produce different amounts" of heat in the different zones, and the sheets are joined together in face-to-face relationship with the ink layer located between the sheets to thereby provide a bilayer laminate of dielectric material as a support- structure for the ink layer.
2. The laminate of Claim 1 wherein the microwave inductive substance is selected from the group consisting of electrically conductive carbon particles and metal particles.
3. A laminate for heating a food product in a microwave oven comprising, as a backing sheet a substrate formed from material that is transparent to microwave energy and having a printed susceptor layer as a coating lamina thereon, said lamina comprising a cured dispersion composed of an apparently homogeneous microscopically heterogeneous mixture of two or more finely divided phases comprised of an organic printing ink vehicle, said vehicle comprising a dispersion of an organic resin in water to serve as a film forming matrix in which is uniformly and homogeneously suspended at least two other kinds of dispersed particles, one kind of dispersed particle comprising electrically conductive microwave interactive carbon particles and the other kind comprising electrically nonconductive attenuator particles that are non- interactive with microwave energy and which comprise a suspended mineral powder for dissipating, spreading out or modulating the energy received by the conductive particles whereby the dispersed phase of the susceptor comprises the aforesaid two forms of intermixed suspended particles of which only. the carbon particles interact directly with the microwave energy and both the carbon and the attenuator particles are of a size sufficiently small to remain dispersed in the ink vehicle until printed upon the substrate.
4. The laminate of Claim 3 wherein an additional lamina of microwave transparent sheet material is bonded over the susceptor lamina to thereby enclose the susceptor between the substrate and said overlying lamina.
5. The laminate of Claim 4 wherein the substrate and the overlying lamina comprise paper layouts and said paper layers are bonded to one another by means of an adhesive layer and the printed-on susceptor is self-bonded to the substrate paper layer.
6. The laminate of Claim 3 wherein the printed susceptor has printed areas with different amounts of ink printed in different areas to provide a greater amount of heating where a greater amount of ink is provided.
7. The printed susceptor of Claim 6 wherein some of the printed areas are printed in a pattern with open unprinted areas comprising a selected percentage thereof.
8. The laminate of Claim 7 wherein a center portion of the susceptor is printed more solidly than a peripheral portion at an outer edge thereof to provide a greater amount of heat at the center and a reduced amount of heat approaching the outer edge of the susceptor. 9. The laminate of Claim 3 wherein the printed susceptor has a configuration corresponding to the shape of the product being heated.
10. The laminate of Claim 3 wherein a layer of an insulating material is imprinted upon a surface of the laminate in alignment with the susceptor and the insulating material is located opposite said product to be heated thereby reduce the loss of heat from the susceptor and to maximize the transmission of heat therefrom to the product being heated.
11. The laminate of Claim 3 wherein the vehicle is a fluid dispersion of a solvent and a member selected from the group consisting of an acrylic resin, a maleic resin, a protein and shellac.
12. The laminate of Claim 11 wherein the vehicle contains a minor amount of a polyhydric alcohol, a wax and an amine to modify the characteristics of the ink.
13. The laminate of Claim 3 wherein said electrically conductive particles include suspended metal particles.
14. The laminate of Claim 13 wherein the metal particles comprise aluminum flakes, bronze flakes or nickel flakes.
15. The laminate of Claim 6 wherein at least one of said areas comprises a dot or grid pattern.
16. A method of producing a microwave interactive susceptor for heating a food product in a microwave oven -. comprising the steps of, a) providing a microwave transparent sheet, b) applying to the sheet as a liquid a homogeneous aqueous dispersion of a plastic resinous film former in particulate form together with at least one microwave interactive component in finely divided particulate form uniformly and homogeneously dispersed in the liquid so as to distribute the liquid dispersion containing the particles of film former and microwave interactive material over the sheet, and c) drying the liquid component of the dispersion so as to cause the resinous film forming particles to fuse together to form a supporting matrix for the dispersed microwave interactive particles to leave said interactive particles in such distribution as to insure that said interactive particles produce heat when exposed to microwave radiation.
17. The method of Claim 16 wherein there is also provided in the dispersion a microwave non-interactive mineral attenuator in finely divided particulate form uniformly and homogeneously dispersed throughout the liquid to provide an apparently homogenous microscopically heterogeneous mixture of at least two kinds of finely divided particles uniformly distributed throughout the fused resin particles.
18. The method of Claim 16 wherein the interactive particles are carbon.
19. The method of Claim 16 wherein the sheet comprises paper, paperboard or plastic.
20. The method of Claim 19 wherein an additional layer of microwave transparent sheet material is bonded to said sheet on the same side as the dried dispersion so as to encapsulate the dispersion therebetween to thereby form a trilayer laminate in which the dried dispersion is sandwhiched between said sheet and the sheet material.
21. The method of Claim 16 wherein the sheet comprises a portion of a receptacle, a food product is placed within the receptacle proximate to the dried dispersion to receive heat from the susceptor when exposed to microwave energy.
22. The method of Claim 21 wherein the food product is popcorn, pizza potato.
23. The method of Claim 16 wherein the dispersion is applied in different thicknesses in different areas to thereby provide a greater amount of heating in selected areas and a reduced amount of heating in other areas where less of the dispersion is applied.
24. The method of Claim 16 wherein the dispersion is applied to the sheet by printing.
25. The method of Claim 16 wherein the dispersion is applied to the sheet in a predetermined pattern, said pattern having a selected outline corresponding to an area to be heated and surrounded at least in part by an uncoated area.
26. The method of Claim 23 wherein a greater amount of - the dispersion is applied in a central area and declining amounts thereof are applied proceeding outwardly toward the edge of the dispersion.