JPH05509434A - Microwave field modifier coated with a pattern of discontinuous electrically conductive elements - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Microwave feed coated with a pattern of discontinuous electrically conductive elements Ludo modifier technology field The present invention is a microwave field model for use in microwave oven heating and cooking. Regarding spraying, in particular spraying and/or To create a high surface or surface heating and deep microwave heating of the lower layer of the food or overcooking and/or overheating the food. Avoid exposing areas under or adjacent to food to microwave energy. or even to easily form a uniform microwave energy field. Concerning microwave headband modifiers that affect microwave energy in order to .

Background of the invention Microwave ovens quickly heat cooking or baking items, especially food ingredients have the ability to Unfortunately, microwave heating has drawbacks.

For example, microwave heating in today's microwave ovens produces even and uniform blowing. It failed to achieve the desired results in terms of sticking, drying and reproducibility. Ma These and other desired results for microwave ovens are achieved by using microwave susceptors. and/or the use of microwave range modification devices such as microwave shields. .

Microwave susvectors and shields, and other similar materials and constructions Check the chroma wave reflectance (R), absorption rate (A) and transmissivity (T) or correct RAT ratio. have The RAT ratio is reflected by (R), absorbed by (A), and the material or by the percentage of microwave energy transmitted through the structure (T). It is measured. Therefore, the sum of the values of R, A, and T is 100%. .

Typically, microwave shields are relatively transparent to microwave energy. have With respect to the RAT, the shield has a relatively low T value. microwave Examples include highly electrically conductive materials such as aluminum foil. can be lost. Shields are usually non-heating elements, but shields are generally non-heating elements, but shields are It is also a septa and vice versa. Therefore, the shield tends to generate that heat. It is an element that has a relatively low T regardless of orientation.

Generally, microwave susceptors are by generating large amounts of heat when placed in a chroma wave energy field. This is a device that responds to The susceptor absorbs some of the microwave energy and This is directly converted into heat useful for drying and spraying materials, for example. Therefore, Typically, microwave susceptors have relatively high microwave absorption values (A).

In addition to high absorption rate, Susceptor converts absorbed microwave energy into heat including equipment for For example, heat can be induced by microwave-induced molecular or Induction caused by so-called any-square R losses in equipment that is electrically conductive or electrically conductive. from electric current or from heating of the insulation of insulating materials placed between electrically conductive parts The type of element or region of heating that occurs is hereafter referred to as fringe region heating or capacitor. referred to as quantity heating.

As previously mentioned, microwave susceptors and other materials and structures are influence the distribution of microwave power within the oven, i.e. they interacts with the microwave energy in the oven due to its RAT properties, and the microphone Modify the radio wave energy field. Therefore, the microphone in the microwave oven Devices and structures that change the power distribution of microwave energy or microwave energy , collectively referred to as microwave field modifiers. Microwave heater (e.g. For example, materials used in microwave ovens as susceptors and reflectors. Various teachings are disclosed regarding devices and devices.

For example, on October 28, 1980, William A. U.S. Pat. No. 4,230,924 issued to Brastad et al. Disclose methods and materials for pre-packaging food to achieve roning . Such materials can be applied in the form of relatively thin films or relatively thick foils. An insulating wrapping sheet with a flexible metal coating such as aluminum Yes, the coating will expose the conductor strips on the wrapping sheet. A large number of individual metals separated by non-metallic gaps in the resulting Criss-Floss Divided into islands or pads. Orthogonal paths of such metal islands The turns are shown and the range of island sizes and island spacings are shown.

In thin film embodiments such as blasted, microorganisms within thin metal coatings Chronic wave heating (e.g. electrical current heating in thin vapor deposited metal coatings) and e.g. A microwave device that can directly microwave food wrapped in a ping sheet. There is a balance in the degree of wave penetration.

In relatively thick foil embodiments, the microwave-reflecting foil may be used. microwave induction in strips of insulating material placed between isolated islands. (i.e., fringe field heating) and uncovered insulation strips. There is a balance between the degree of microwave transparency of the sheet through the top.

U.S. Patent No. 4,883,9 issued to Maynald et al. on November 28, 1989. No. 36 provides a patterned coating with a large depth.

1 Q RQ L no's day' Q I:l Ij Ijishoku h-f-* -mon,, , we have opened the door to controlling heating through microwave interaction through radical activation. Show. This is thinned out in the process of creating a susceptor with patterned active areas. Process the inactive parts of the new film susceptor.

U.S. Patent No. 4.864.089, issued September 5, 1989 to Tyne, Localized microwave radiant heating through the use of coating media is disclosed.

It controls the conversion efficiency by the amount of conductors and the amount and selection of semiconductors in the medium.

U.S. Patent No. 4 issued to James L. Stone on December 12, 1989. , No. 866.232 opens food packages for use in microwave ovens. The oven has metallized insulators in areas of the container where high heat is required. area of the container to provide microwave protection and/or microwave protection. It has a metallized ink laminate. Stone doesn't use data to do this. The ink laminates are made of the same material for different degrees of heating and shielding. The same states that there are different thicknesses and densities.

U.S. Patent No. 4 issued to Turpin et al. on February 27, 1990 , 904,834 discloses a microwave heater and manufacturing method, which heating is carried out in a microwave lossy coating material with an inverted penetration depth in the range of Other areas of lost material are arranged in a predetermined array with smaller or parallel columns. ing.

Upper + jO + V horn hz black - Yamatomo C! 47 Cocurro 1096 applicant application 0345 No. 523 discloses a microwave susceptor having multiple regions, within which At least one region is alternately achieved by splitting the susceptor surface. . This microwave range modifier has a surface and a certain amount of electrical conductor coating. Includes a substrate having a material.

The coating material is disposed on the surface of the substrate and is a plan view of a plurality of ears.

FIG. 6 is an enlarged partial view of another microwave region embodiment shown in FIG.

Figure 7 has an integral cover with a processable food product placed therein in the open position. FIG. 2 is a perspective view of a preferred package.

FIG. 8 is a partial cross-sectional view taken along section line 8-8 of FIG.

Detailed description of the invention An exemplary microwave domain modifier of the present invention designated generally as 20 in FIG. The ear is formed from a substrate 22 and a plurality of electrically conductive discrete elements thereon. an array in which This electrically conductive discontinuous element is a region of the substrate 22. may be formed from a pattern of coating the coating material over the area. preferable.

This element 24 preferably has an elongated section and is arranged side by side and in relation to each other. It is preferable that they be arranged alternately.

As used herein, the term elongated has its ordinary meaning, e.g. This means that it has a very long shape in terms of width. Furthermore, the elongated element It is preferable that the groove 24 be roughly straight, but it may be curved or wavy. This does not exclude shapes and curved shapes. Also, elongated element 2 4 has a circular shape as shown to reduce the tendency for electrical arching. do.

A staggered relationship, as used here, is an elongated, rectangular extension of a side-by-side relationship. and rectangular elements 24, but having offset ends from each other. do.

This displacement is not necessarily uniform throughout the array.

Generally (and therefore without specific reference numerals) the microwave domain model of the invention A fifer is a discrete unit that covers the entire substrate or a portion thereof. similar To do this, place several modifiers in different areas on the same board that change their effect. can be placed. The modifier has a layered array. For example, array can also be placed on both sides (side surfaces) of the substrate. As an alternative, modify a. Packages including packaging materials, cartons, containers, cookware and the like. can be integrated into selected parts of the engine.

In addition, modifiers are used for strength, arc suppression, and mutual modifier action. may be a layered or laminated structure with one or more additional layers as . For example, although not shown in the drawings, thermoplastic or thermoset coatings or Apply the film to the modifier structure and cover the electrical conductor coating material directly between the electrical conductor coating material and an adjacent load such as a quantity of food. electrical contact, and if the modifier is placed in close proximity to electrically conductive objects. protect the modifier from electrical arcing. Furthermore, such a layered structure done by a pattern coating a curable film with an electrically conductive material. , laminating pattern coating films onto paper, cardboard or other insulating substrates. This is done by

A pattern of electrically conductive discrete elements coating a substrate with a coating material formed by. The advantages of this structure over traditional thin film susceptors are There is a significant reduction in cost and number of parts. Printing and coating material More preferably, it is applied to the substrate, most preferably by rotogravure printing. Yes. Printing offers cost and effective savings over other coating processes and roto-glue Labia printing equipment is commonly available in carton makers.

The coating material of the present invention is a binder containing a resin and a solvent and electrically conductive particles. Including da material equipment. Additionally, the coating material includes various other components.

Binder devices are used to bind electrically conductive particles together in contact relationship be done. The binder system also has the function of bonding the coating material onto the insulating substrate. . The binder device includes a resin and a solvent. An exemplary preferred material is Trocellulose, ethylcellulose, polyvinyl butyl, polyvinyl pylori Contains poly(methyl vinyl leather/maleic acid) copolymer resin and acrylic. nothing. Nitrocellulose is manufactured by Sun Chemical's General Prix in Cleveland, Ohio. 18-25CPS RS nitrocellulose from Inking Ink Division. Can be purchased as a 40% solvent (this solution is 17% isopropyl by weight). lopyl alcohol.

23% ethyl acetate, 20% n-propyl acetate). ethyl Cellulose was produced in Plowea, Rylington under the name ethylcellulose N-4. It can be purchased from LeCure. Poly(methyl vinyl leather/maleic acid) The copolymer resin has a trade name of Ganrrett and Uniin New Jersey - Uniin's G. It can be purchased from AF. Ganzlets is a registered company of GAF Corporation. It is a registered trademark. Ganretto currently has three basic forms, Ganretto AN, and Garetto. There are N'Rets ES and GanzRets S, but I prefer GansRets ES-225. Yes. Polyvinyl butyl is manufactured by Somerville NJ Houxt under the trade name Moutal. - Can be purchased from Celanese. It is available in several molecular weights It is Noh. This preferred type is B-201, B- Classified as 30H and B-30T. The trade name Moator is Houxtserani. registered as a registered trademark of Polyvinyl pyrrolidone St, Royce Mosouri's new chassis and Sigma Chemical GAF Corporation resin way can be obtained from

The electrically conductive material used to make the coating material consists of pure metal particles, Contains metal oxides, alloy particles, carbon particles and graphite particles. Furthermore, conductive particles are Preferably, it has an irregular shape, and more preferably, it has a relatively flat shape. preferably have different shapes and sizes, the entire electrical connection between the elements Promote contact.

Preferred conductor particles that are effective include Ni-Nibame, Inc., Uykotzow NJ. It is Kell Flake HCA-1. Nickel flake HC purchased from Nobame Co., Ltd. A-1 are dendritic particles in the shape of a spheroid connected together and flattened . Preferred conductor particles have a flat tree-like shape. The second preferred particle is Purchased from Cobot in Walthammas as Carbon Black Regal 99R. be able to. The particles are relatively flat and have a size of 1,36 nanometers. Ru.

Some other components used as constituents of coating materials are adhesive solvents , emulsions, acids and liquid materials that are chemically identical to the other constituents of the coating material. After being incorporated and added in liquid form, the coating material is solidified.

In coating material applications where a certain flexibility is required, the coating material has a thermoset material. . Additionally, anti-cellaring materials or other constituents may be present in the coating material formulation. included.

Furthermore, the undercoating placed on the substrate before printing increases the conductivity. Ru. Similarly, an overcoating placed over the element increases the conductivity. let Furthermore, conductivity is determined by both undercoating and overcoating. Increased by using . undercoating and/or overcoating The coating binder is further increased by the conductive binder of the coating material. Use the same solvent as the one used. As a result, undercoating or overcoating - Coating preferably uses the same material solvent as the coating material and Preferably, undercoating and overcoating are based on the coating material. Use the same solvent as the binder.

Furthermore, increasing the acidity of the binder provides economical effects regarding conductivity. can be made to grow. Increasing the acidity makes the binder more conductive. subordinate Additive-forming acidic binder additives, such as complex acids, to the coating material. It is advantageous to add While unbound, the chemical effects of the absorbing surface can benefit this give benefit.

This absorption brings the metal particles closer together giving even better conductivity. Can be done. Also, salts are formed by oxygen which creates metals more freely in electrical conductors. It is formed.

FIG. 1 shows an exemplary microwave model designated by 20 embodying the present invention. Show fire. The substrate 22 in FIG. 1 is a carton for packaging microwave foods. A 20-point carton board, e.g. Heat, cook, or bake the contents of the package without removing the contents from the The package is suitable for being placed in a microwave oven for Ru. Other exemplary substrates 22 are carton board, coated carton board, thermoplastic Contains plastic films, thermoplastic non-fibers, thermoset plastics or ceramics. nothing.

Disposed on the substrate 22 is an array formed of a plurality of discrete elements of electrical conductor. It is placed. In FIG. 1, the array has a coating material 26 covering a peripheral area 29. It extends over the entire top surface 28 of the substrate 22 except for the top surface 28 of the substrate 22. This peripheral area 29 is electrically conductive. between the body element 24 and the metal material located adjacent to the modifier 20. The edges of the modifier 20 are insulated to substantially prevent arcing. It acts on Furthermore, the array of FIG. 1 extends over the entire surface of substrate 22. However, the modifier is confined to one or more regions of substrate 22.

Referring to the enlarged cross-sectional view of FIG. 2, it can be seen that the size and shape of It includes an element 24 that is uniform and has a length and a width W. Therefore, this array is Preferably, the element 24 has a uniform shape. Furthermore, this element 24 are linearly aligned in a row of straight lines parallel to each other. This column is specified by SL. They are arranged in a straight line with a fixed distance between them, and the rows arranged in parallel are The widths are separated by a distance of SW. In addition, co-located and adjacent The elements are staggered so that they are linearly displaced by the distance dictated by O8. It's off. The percentage of deviation of such an array is (O5/L)(100 ).

Referring to FIG. 3, the elongated elent 124 is a book having a generally serpentine shape. Another embodiment of the inventive microwave domain modifier 120 is shown. this In an embodiment, the length of element 124 is cut along its centerline. death modifier in the shape of the element 124 and the degree of stagger. Reference numeral 120 has substantially the same structure as the modifier 20 in FIG. Therefore, the substrate 12 2 is an insulating material similar to that of the substrate 22 in FIG. 1, or may be a different insulating material. This The elements 124 differ in size and/or shape; similar or different coating materials (e.g. coating materials with different surface resistances) has. In this array, this element in the adjacent column as shown 124 is off by about 50%.

Modifier 120 in FIG. 3 has more isotropy than modifier 20 in FIG. do. In short, the effectiveness of the array as a shield depends on the incoming microwaves. This reduces the dependence on the direction of the array. The R value is determined using the RAT test described below. If plotted against degree of rotation of 360” using A line is obtained. In the modifier 20 of FIG. 1, the maximum value R is relatively high. , this part of the curve is relatively wide. Additionally, the lower radius portion of the curve is relatively narrow. figure At a modifier 120 of 3, this curve has the same shape, but , the maximum value R is small, the low R part of the curve is narrow, and the high R part of the curve is wide. follow The modifier 120 has more isotropy than the second modifier 20. is, even if its maximum value R is small, this wave is transmitted at all angles in the microwave oven. This provides better isotropy within the microwave oven. In this example The length of the elongated section is the largest passage along the centerline. In this example , the three possible paths are identical in length. In this example column, Y-shaped The stem of the Y-shaped element 324 is connected to the stem of the arm adjacent to the Y-shaped element 324. Partially in between. The arms of Y-shaped elements 324 in adjacent rows are in parallel relationship with some of the lateral arms of the Y-shaped element 324.

The heating of the fringe region is determined by the spacing between adjacent Y-shaped elements 324 as well as by the Y-shaped elements 324. The size of the shaped elements 324, the width of their elongated portions and the material of the substrate 322. This can be varied within the array by changing the dielectric loss characteristics of the materials.

Compared to modifier 20 similar to FIG. 1, this modifier 320 is more isotropic. For example, such a modifier 320 has a microwave Less sensitive to positional variables when placed in an oven and has a lower maximum R value Become.

As mentioned above, the shield is relatively transparent to microwaves. It takes The shield has a relatively low value of T. Therefore, preferably the shield is about 40 % or less, more preferably about 10% or less, and most preferably about It is less than 5%. Due to their low T value, shields usually have a high R value . The shield can prevent overheating in certain areas, such as corners and edges. It is especially used for the purpose of preventing heating and generally slowing down microwave cooking. Ru.

Some modifiers have their microwave reflectance, absorption and transmission values, i.e. It is characterized by its RAT value. However, the shield and in particular R and T, the RAT value is particularly informative with respect to shielding performance. It is.

One way to measure RAT values is with the following Hewlett-Barackard device, model 8616A Signal Generator, Model 8743A Reflection Transfer Test Unit l-, Model 8411A Harmonic Frequency Converter, Model HP-8410B Circuit Analyzer , Model 8418A Auxiliary Display Holder, Model 8414 Polar Display Ray Unit, Model 8413A Phase Gain Indicator, Model 5920 Low Power Wave Guide using a double termination and two 5281A coaxial wave guide adapters.

Additionally, a digital millivolt meter is used.

The RF corrected power output section of the 8616A signal generator is connected to the 8743A reflection transfer test unit. Connect to the RF input section of the kit.

8411A harmonic frequency converter to 8743A reflection transfer test unit cabinet and the 8410A network analyzer. test chi channel output section, reference channel output section and test phase output section of 8410B. 418A auxiliary display holder test amplification, reference and test phase inputs. Connect each. This 8418A auxiliary display holder is the 8414A auxiliary display holder. Includes cabinet connection to polar display unit. 8413A position The gain indicator connects the cabinet to the 8414B network analyzer. have The amplifier output and phase output of the 8413A phase gain indicator are digital. Connected to the input of the millivolt meter.

The settings for the 8616A signal generator are as follows. The frequency is set at 2.450GHz. is set, the RF switch is turned on, and the ALC switch is turned on to stabilize the signal. The ALC output cup was used to zero the DBM meter and the operating range was 11 db. Set the attenuation in the 8410B Network Analyzer Frequency Range Set to 2 or 5 to make the reference channel level meter the operating range.

Amplitude gain to zero voltage meter reading for reflection and transmission measurements respectively Set the knob and amplitude Bernier knob appropriately.

The microwave field sample is a 3.5 inch (8.89 cm) straight It has a diameter.

In the reflex position, the 8743A reflex transmission unit is in reflex mode. A 52 81 Coaxial Waveguide Adapter does not fit the 8743 Reflection Transfer Test Unit Connected to minutes. Fully shielded (aluminum foil) with 5281 conductor A plane between the reflective side of the wave tube adapter and the 3290A low power guide termination. It is laid out flat. The amplified voltage is determined by the amplification gain and the 8410B network analyzer. Set to zero using Iaza's Bernier knob. This shield is microwave Replaced by field modifier sample. In short, this sun The pull is a 5281A coaxial waveguide adapter and a 5920A low power waveguide termination. and the attenuated voltage is measured. Typically 4 readings per sample. A sample is taken and the decay voltage is measured. Typically, the sample is rotated 90° for each measurement. be done. After this second sample is completed, this sample is used for the second and final measurement. (from top to bottom). Read maximum and minimum values in polarization In order to do not have.

The R value is the maximum reading. These samples are rotated over 90''.

In the transmission position, the 8743A reflex transmission unit is in transmission mode. 10db The attenuator is connected to an 8743 reflection transfer unit and a second 5281A coaxial waveguide adapter. located on the transmission side of the line between the "in" boats.

The two 3281A coaxial waveguide adapters are aligned and secured together. . This amplitude signal voltage is determined by the amplitude gain and Bernier of the 8410 network analyzer. Zeroed using the knob. Two waveguide adapters with modifier C to be tested the attenuated voltage is measured. 4 readings in reflection measurement This is done as described above. Reflection and transmission values are calculated similarly, i.e., average or maximum. Large is calculated.

Absorption is calculated by subtracting the transmission and reflection measurements from 1,00.

The RAT value, as measured by a network analyzer, is The actual RAT value when the modifier is placed to compete with the food load. It is important to note that there are differences. Food and microwave domain modifiers compete for available microwave energy. This conflict is caused by two impedances analog to a circuit consisting of a generator connected in parallel to the load. this The generator represents a magnetron, one impedance load represents the food load, the other The impedance load represents the microwave domain modifier. This network The QAnalyzer does not include a food load register.

Therefore, when a food load is applied to the circuit, the microwave domain modifier resistance is unknown. The impedance of the food load is the impedance of the modifier. – Significantly smaller than the dance, most of the energy will flow through the food. Probably. As a result, the modifier design is based on the actual food being heated. Contains some trials and errors. As mentioned above, the susceptor is in the microwave range. Microwave domain models that absorb microwave energy and heat when exposed to It is a firer.

for heating (at least with respect to other microwave field modifiers) One way to determine the power of the modifier is to determine the energy -It is a competitive test. 30B as measured by 1000g water load Preferably by using a microwave oven with a power of TU/min. has a ΔT at 2 minutes of about 90'F or greater, more preferably about 150' F or higher and more preferably 200'F or higher.

To implement the energy competition test, 30 grams of Crisco (trade name) oil microplates on 3- and 3-1/4-inch diameter Vilex Petri dishes containing microcells. 150ml of Pyrex with 100g of distilled water in a wave oven Place the beaker. These items are juxtaposed approximately 9 inches off center. Ru. First, read the oil temperature. Microwave these items for just 2 minutes. Apply power to the entire area and open the microwave oven at 30 second intervals. Stir the oil with a thermocouple and record this temperature. This measurement determines the best way to cool the oil. Done as quickly as possible to make it as small as possible. This procedure provides control.

3 and 1/2 diameter sun of microwave range modifier immersed in oil Repeat the steps described above for the pull. Start with the same initial oil in its control.

Glass lock on top of modifier to keep it submerged in oil It is necessary to place an inert weight, such as a This data is 70″F Subtract the initial temperature displaced from 70' from each temperature recorded. Standardize by adjusting by subtracting or adding.

Once tested, a comparison of various microwave range modifiers can be used. One method used is to compare the change in temperature over a 2 minute time interval. be. In this way, the 2 minute ΔT is calculated from the 2 minute ΔT of the oil and the susceptor. It is calculated by subtracting the minutes. Furthermore, the 2 minute △T of the susceptor is from 70″ It is normalized by adding and subtracting the initial temperature change of the oil. Net Energy competition can be reduced by using RAT through the use of work analyzers. The test will show how the microwave modifier heats up when connected to the food load. It is not possible to accurately predict the However, due to the characteristics of water loading, actual food The greater the change in the microwave properties of the load, the less accurate this test will be. do. As a result, within a specific application comparing the possible microwave ranges Achieve desired results by actual food loads using other water volumes or competing loads It is desirable to reduce the number of trials and errors required to In many cases In this case, some trials and errors are unavoidably necessary.

Notwithstanding the foregoing, the microwave domain modifier of the present invention has certain variables. name to provide the desired RAT value and heating characteristics by selectively changing the Can be created by trial and error ◎ Therefore, modification A can be designed with a wide range of shielding and heating properties. Ru. Some of these variables are related to the array, i.e. the shape of the elements, the size Regarding the size, orientation and configuration of other elements, some coating materials Finally, regarding overcoating or undercoating.

In general, the direction of various variables related to creating a RAT can be determined with reference to Figure 2. This will be explained below. However, this orientation applies to all embodiments of the invention. be done.

Among the variables of the array are length, width, and staggered arrangement between adjacent elements 240. (stagger) degree is included. One variable is the length of element 24.

Normally, the maximum length of the element is preferably about 4 cm or less, and is preferably about 3 cm or less. Furthermore, the length is preferably (1/2) am or more; More preferably, it is 1 cm or more. In many cases, L will cause an electrical arc. smaller than the amount. In this normal range, increasing length increases the microwave reflection. increase and decrease both the microwave absorption and transmission of modifier 20.

Furthermore, the increase in the length of element 24 reduces the amount of alternating current induced in element 24. increasing the magnitude of the pressure and current and increasing the end gear between adjacent elements from that end. increases the tendency for arcing that can occur across caps.

Regarding width W, approximately 0.001 inches (0,00254 centimeters) to 1, A width of 0 inches (2,54 centimeters) is preferred, and even 0.010 (0.010 cm) width is preferred. ,0254 cm) to 0.10 inch (0,254 cm) is preferred. In this normal range, increasing width W decreases the microwave reflectance. Due to the change in wavelength induced by such things coming into contact with the food load, The wavelength band of the modifier 20 that reduces the response of the modifier 20 to increase the width. Further, the elongate element 24 is about 2=1 to about 200:1 , preferably from about 10:1 to about 40:1.

The end-to-end spacing SL is preferably about 0.010 inch to about 0.100 inch. In this range, the end-to-end distance SL or the side-to-side distance SM increases. reduces microwave reflection and increases microwave absorption and transmission of modifier 20. This increases and reduces fringe region heating of the interference portion of the insulating substrate 22.

The side spacing SW is approximately 0.010 inch (0.0254 cm) to approximately 0.01 inch (0.0254 cm). Ten inches (0,254 centimeters) is preferred. Side spacing SW in this range An increase in will reduce both fringe region heating and shielding.

The degree of stuttering is for maximum shielding and high dynamic coating materials. and preferably about 30% to 35%.

Among the coating material variables are the resistivity, shape and size of the conductor particles, and the insulation properties. characteristics (e.g. insulation constant, loss factor and dielectric strength) and dry coating materials including surface conductivity. The surface electrical conductivity of the conductor element 24 is related to the surface resistance. relatively high, preferably less than 100 ohms per square centimeter, More preferably 10 ohms or less per square centimeter, even more preferably 1 ohm per square centimeter or less and more preferably 1 ohm per square centimeter 0.1 ohm or less per torque. In this range, the surface of the element 24 The increase in the electrical conductor of modifier 20 directly increases the microwave reflection. Reduces microwave transmission. It has conductivity in the desired range as described above. Achieving a dry coating that is achievable is aided by certain features. for example, It is important to deposit a sufficient amount of coating material. Further coating The more material, i.e. the thicker the coating material, the greater the conductivity. I hear it. The coating material preferably has a thickness of about 0.0001 inches (0.0002 54 cm) to approximately 0.003 inch (0,00762 cm) ) and more preferably about 0.005 inches (0.0127 centimeters). approximately 0.002 inches (0.00508 centimeters).

The viscosity of the coating material also depends on the coating process used. It is essential. The viscosity of the coating material is about 50 cps to about 7000 cps . For rotogravure printing, measure with #3 zahncap In this case, the viscosity is preferably from about 100 cps to about 175 cps. In either case Even if the viscosity is Suitable for printing, spraying, printing, silk screen printing or rotogravure printing It must be something like this. Achieving the desired viscosity is a common practice in the printing process. Addition of resins, solvents or other materials after the initial mixing of the coating materials such as Additional items are required.

Furthermore, before printing, an undercoating placed on the substrate increases the conductivity let Similarly, an overcoating placed on the element increases the conductivity let Conductivity can be achieved using both undercoating and overcoating. It increases with use. undercoating and/or overcoating If the adhesive in the coating uses the same solvent as the binder in the coating material, The conductivity increases further. As a result, undercoating or overcoating coating is used, more preferably undercoating and overcoating. coating is used, more preferably undercoating or oat coating. Coating method (using the same solvent as the coating material, most preferably i Undercoating and overcoat ink & coating materials using the same solvent as the powder.

Furthermore, the overcoating of Ganzuretsu AN or Ganzuretsu S, For example, it can be used to provide FDA-approved gloss.

Further increasing the acidity of the binder provides a beneficial effect of electrical conductivity. Vine As the acidity of Da increases, the conductivity increases further. Therefore, form additives Adding an acidic binder additive to the coating material, such as an acid complex containing is beneficial. Although not intended to adhere, the chemical effects of surface absorption Provides a TF+j benefit. This absorption causes close contact of metal particles with each other. and further increases conductivity. It is also more self-contained due to its electrical conductivity. This makes it possible to make salts with oxygen, which makes metals.

Electrically conductive particles 1 of the coating material of element 24 are electrically conductive. The particles are preferably 25 microns or less in size (e.g., in their largest dimension). force (preferably, more preferably a size of 10 microns or less) Delicious. Fine particles are defined as ( A produces a large coating conductivity. Also, mixing particles of different sizes is , increases the electrical conductivity of a surface for a given percentage in a given coating material. make it act so as to add to it.

The aspect ratio of the particle, e.g. the ratio of the particle's longest dimension to its shortest dimension, is important. Ru. A high ratio (ie 1:10 or higher) is preferred. This is because the solidified These conductive particles promote electrical contact between particles of the coating material. This is because particles with a small aspect ratio are more susceptible to microwave heating. even higher The resistive particles act to reduce the surface conductivity of the coating material and alternate The particles have a shape and edges arranged in the space between the conductive particles of the coating material. tends to promote electrical contact and increases the conductance of the surface of element 24. There is a tendency to make it bigger.

Regarding the insulation properties of dried binders and other fluids, high insulation loss factors are to increase heat (e.g., capacitive heat within conductive element 24 between conductive particles). The high dielectric strength reduces the tendency to arcing and the high dielectric constant The number increases microwave reflectivity and power handling performance.

Between the remaining variables is the insulation of the substrate 22 and other additional overcoating materials. Properties (e.g. insulation constant, loss factor and dielectric strength) are included. to the board 22 High insulation constants result in microwave reflectivity and power handling, and the coating substrate and other overcoatings or Undercoat to reduce lossy material and, if possible, further conductor coating material. Another possible way to increase shielding is offset The aim is to increase the amount of The methods described above and the list of adjustable variables are all Although not all included, it shows how to adjust to the desired RAT value.

As mentioned above, the relative RAT value of the microwave domain modifier of the present invention is , the electrical conductance or resistance parameters of the surface of the element, and the degree of stagger between elements, length, width, spacing, resistance of conductor particles, shape , size and aspect ratio, and insulating properties of the substrate and/or insulating binder (e.g. e.g., by selectively changing the insulation constant, loss factor and insulation strength). They can also be made to match the specific ingredients of different foods.

Three illustrative examples are provided to demonstrate the transferability of the microwave field of the present invention. One has high shielding properties and low heating properties, and the other has high shielding properties and low heating properties. those with folding properties and high heating properties, those with low shielding properties and high It has heating properties.

Example 1 Exemplary microwave field modifiers of the present invention have relatively high shielding resistance. The relatively low shielding characteristics are shown in Figures 1 and 2. .

This array has 109 meshes and 0.0032 inches (0.008128 centimeters). using a monofilament polyester silk screen with a diameter of This is a silk screen printed on a 0 point carton board. coating material The material is made up of approximately 60% silver particles by weight, with a density of (0.5%) per square centimeter. ) represents a dry surface resistance of less than 1/2 ohm. Such coating materials is available from Archeson Corporation, Port Front, Michigan, and is It is recognized as 477SS.

Referring again to FIGS. 1 and 2, elongated element 24 is 2 1/2 cm long. , with a width of 0.040 inches (0.1016 centimeters) and a width between the ends. is 0.160 inches (0.4064 centimeters) and the lateral spacing is 0.160 inches (0,4064 centimeters), with approximately 25% stagger (pattern offset) OS. This pattern is elongated horizontally on the front side of the board 22. element 24 and a horizontally oriented elongated element on the rear side of substrate 22. ment 24.

Example 2 Exemplary microphones of the invention with high shielding properties and substantial heating capabilities The RF modifier can be described with respect to FIGS. 1 and 2. In this example This heat is absorbed by the relatively high conductivity and insulating properties of the coating material components. The heat is mainly generated by the peripheral area or capacitive between the . Therefore, some heat is generated by R heating of the element 24 itself. Ru. The surface resistance of the dried coating material is less than about 2 ohms.

This array has 109 meshes and 0.0032 inches (0.008128 centimeters). 20 using monofilament polyester silk screen This is a silk screen printed on a dotted carton board substrate 22. used This coating material contains 47% copper and 53% acrylic binder system. coating material manufactured by Acheson Colloids Co., Boat Front, Michigan. It can be purchased from Acheson Copper Electrodag [437].

This array has equipment similar to that shown in FIGS. 1 and 2. This long and narrow Element 24 has a length of (2,0) cm and 0.032 inches (0, 08128 cm). This array is 0.045 inches (0,11 43 cm) end gap, 0.02 inch (0.06858 cm) with a lateral co-gap of 30 cm) and an offset of 30%.

Example 3 See Figure 4 for an exemplary embodiment with low shielding and significant heating capacity. can be explained while doing so. In this example, this heat is transferred to this element 22. 4 due to the relatively low conductivity and insulating properties of the coating material components. It occurs primarily within element 224.

This array has 109 meshes and 0.0032 inches (0.008128 centimeters). diameter polyester monofilament or similar 18-F multifilament. Patent coated on 20-piece carton board using lament silk screen It's a turn. This coating material is 60% nickel and 40% nickel by weight. Composed of nitrocellulose. Nickel is like kola from New Chassis. It can be purchased from Funotsuba Company and is recognized as Nickel HCA Flake. be recognized. This nitrocellulose was manufactured by Sun Chemical Company of Cleveland, Ohio. Nitrocellulose can be purchased from the General Printing Ink Division of Solution [266-133]

This array has a similar appearance to that illustrated in FIG. This element 224 is 7 mm square and 0.6 mm apart from all sides. be.

Additionally, this element 224 is offset by 50%.

Additional illustrative examples using further various binder devices are provided below. .

Example 4 This is an example using a 10% solution of Mortal's B50H polyvinyl butyral. This is an example. A 10% solution is made using 45 grams of methanol (methyl alcohol). It can be obtained by dissolving 5 grams of B50H powder in a solution of others For this purpose, add 75 grams of Tuba nickel, 60% nickel and 40% (10%) % solid resin) Make a resin solution. As a result, the final solution contains 75 grams of nickel and 50 grams of a 10% resin solution.

This coating material is screen printed in a pattern similar to that in Figure 1. It will be done. The size of this pattern is as follows. End gap SL is 0.045 inch (0,1143 cm), side gap SW is 0.275 inch (0,6985 cm), length L is 0.78 inch (1,99898 cm) centimeters), width W is 0.035 inches 5- (0,0889 centimeters> cm) ) and an overlap of 31%.

Additionally, this coating material can be easily removed using a doctor blade or Meyer rod. Polyvinyl butyral solution (i.e., nickel-free meth) on a substrate such as a carton board pre-coated with a 10% solution of The conductivity and reflectivity (R) will increase if screen printed on the screen.

The first sample creates an overcoat of the susceptor coating. If coated with the same 10% solution, the change in RAT properties will be similar to that of the undercoat. The same characteristics as the second sample with

A sample growing polyvinyl butyral undercoating is undercoated. Nickel printed sump with both coating and overcoating The conductivity and reflectivity (R) are further increased if coated to create a Ru.

Example 5 This example uses a 20% solution of Ganrett ES-225. This 20% solution is , 20 grams as added (50% resin and 50% No ethanol solution) This can be obtained by starting with the following materials. This is 10 grams of resin and 10 gives a solution of grams. By adding 30 grams of ethanol solution to the solution to make a 20% resin and 80% solution. This is 10 grams of resin and 40 grams of resin. grams of solution or a total of 50 grams of solution. Add to this 75 grams of Nova Novamet nickel added, 60% nickel and 40% (20% wood) Make a resin solution coating material. Therefore, the final solution is 75 grams. of nickel and 50 grams of a 20% resin solution.

This solution was sprayed in a pattern similar to that in Figure 1 (with small adjustments to viscosity). Clean printed or rotogravure printed. The size of this pattern is as follows. It's good. 0.045 inch (0.1143 cm) end gap S L, width W2 of 0.0275 inch (0.06985 cm) and 31% It is a stagger.

Example The example uses a 10% solution of polyvinylpyrrolidone. 10 percent solution The solution is 45 grams of methanol (methyl alcohol) and 5 grams of polyvinyl resin. It can be obtained by melting Loridone powder. This and 75 grams of saliva 60% nickel and 40% (10% NO solid resin) resin solution with nickel loading. Make a liquid. Thus, the final solution contains 75 grams of nickel and 50 grams of nickel. with a 10% resin solution.

This solution is screen printed in a pattern similar to that of FIG. This pata The size of the ring is as follows. 0.045 inches (0.1143 centimeters) end gap SL, side gap SW 0.275 inch (0.6985 inch) centimeters), 0.78 inches (1,99898 centimeters) ( 7) Length, 0.035 inches (0,0889 centimeters) Width W and 31% This is an overlap.

Example 7 This example uses a 5.4% solution of ethylcellulose. A 5.4% solution is 2. Obtained by starting with 2 grams of ethylcellulose resin. to this Add 0.5 grams of non-solid material such as Bentone SD2.

The material was manufactured by National Lead Chemical in Hydestone, New Chassis. Available from. Obtained from Union Kambu Co., Ltd. of Uniin, a second chassis. Possible UNIRET 7055 (Tsyumaric acid modified rosin ester binder) and Herculon, available from Vercules Chemical Co., Wilmington, Delaware. 1.8 grams of plasticizer such as (hydrogen-treated methyl ester) Add. Also added 32.1 grams of n-propyl acetate and added 5.4% ethyl acetate. cellulose solution. Add to this 59 grams of Tuba Nickel HCA flakes. of 59% nickel and 41% (5.4% resin) of ethyl cellulose resin solution. Create liquid coating materials.

Therefore, the final solution contains 59 grams of nickel and 41 grams of 5.4% wood. Consists of a fat solution.

This solution has a pattern similar to that in Figure 1 (with only minor adjustments to viscosity). Therefore, it is screen printed or rotogravure printed. size of this pattern is as follows. 0.045 inch (0.113 cm) end gap SL, 0.0275 in. (0.06985 cm) lateral gap. SW.

0.78 inch (1,99898) long 10.035 inch (0,088 9 cm) and a stagger of 31%. relatively high & relatively Various combinations of relatively high and relatively low heating capacities with low shielding Modifiers with various properties can be designed from the above examples including I understand that. In the example above, high shielding reduces transmission by about 10% or less. High heat has a ΔT of about 125°F or more in 2 minutes, so that It is formed so that

The above-mentioned microwave field modifier of the present invention can be used for heating, baking, etc. It can be used in a variety of food items, such as packaging, shoes, etc. Figure 7 and figures 8, Printed Microwave Film for Cupcake Batter Food Approx. A package 130 is shown having a field modifier. carton 13 0 is commercially available from IVEX, Newton MA, which splits butter. Includes eight possible metallized thin film susceptor cups 54. alternatives and This cup 54 is then heated by the microwave field of the present invention, which is designed to heat the cup 54. Consists of domodifiers. These cups 54 are filled with butter 52 and are lightweight in an annular direction around a centrally located spacer 55 used as a cup. It is located.

The base side walls 41, 42, 43 and 44 of the carton 30 are the modifiers 2 of Example 1. Microwave field modifier containing an element similar to element 24 of 0 Printed by fire 420. The inner surfaces of side walls 41, 42, 43 and 44 are horizontal having an array of elongated elements 24 running along the side walls 41, 42, 43 and 44. The outer surface is an identical array of vertically oriented elongated elements. This modi Fire 420 to slow down the baking at the edges and the baking Provides shielding around the sides for even coverage.

A second modifier 220 is printed on the inner surface of the lid 35 of the package 30.

This is modifier 220 as in Example 3 and FIG. 4, but with element 224 are aligned in the orthogonal direction. This modifier 220 generates a significant amount of heat, This heat blows the surface of the cupcakes, giving them the traditional dome-shaped top shape. to assist in giving. While specific embodiments of the invention have been illustrated in the drawings, it will be appreciated by those skilled in the art that Various other modifications and changes may be made without departing from the spirit and perspective of the invention. it is obvious.

It is intended that the claims cover such changes and modifications that fall within the scope of the invention. This is what is intended.

In particular, each of the arrays of elements mentioned above is an element of uniform shape and size. elements, but excludes arrays with elements of non-uniform shape and size. It is not something that can be removed.

ig 4 Fig, 3 Summary book Discontinuous or e.g. packaging or backing or wrapping types material or resistant or integrally incorporated into disposable tackware patterned microwave field modifier for microwave ovens (20). This modifier is used to form electrically conductive elements. a plurality of discrete surface areas coated with a conductive coating material (24); However, the discrete elements of a given surface are arranged in a given array. preferred Preferably, the elements are elongated and the array is arranged in a straight line with the columns in parallel relationship. Align elements so that adjacent columns have a staggered relationship. Configure multiple columns.

An electrically conductive element is an electrically conductive ink-like coating on an insulating substrate. Preferably, it is formed by printing on a mating material. Micro like this The relative values of reflection, absorption and transmission of the wave field modifier are determined by the surface of the element. Electrical conductors, length, width, degree of stagger between adjacent elements, and coating the resistivity, shape, and size of the electrically conductive particles of the material and the insulating properties of the substrate; / or by changing other characteristics of the coating material to meet specific requirements. It can be made by

International search report. rrtnc　011111tls

Claims (12)

[Claims] 1. an insulating substrate having a surface and an amount of electrically conductive coating material; In microwave field modifiers where coating materials are Said is laminated to the surface of the substrate to form electrically conductive discontinuous elements. The discrete elements are elongated and arranged in a predetermined array, preferably adjacent within the array. arranged in a predetermined array of a plurality of linear rows in tangential relation; The linear rows of electrically conductive elements are arranged in parallel juxtaposed relationship and further Preferably in adjacent linear rows the discrete elements are of staggered relationship. further preferably the discontinuous elements are of uniform length; Microwave field modifier. 2. an insulating substrate having a surface and an amount of electrically conductive coating material; In microwave field modifiers, the coating material is Laminated to the surface of a substrate to form electrically conductive discrete elements The continuation elements are approximately square, uniform in size, and arranged in a staggered relationship. arranged in a predetermined array having two or more substantially parallel columns; A microwave field modifier featuring: 3. an insulating substrate having a surface and an amount of electrically conductive coating material; In microwave field modifiers, the coating material is Laminated to the surface of a substrate to form electrically conductive discrete elements Continuous elements are formed such that each element has an elongated shape, and adjacent discontinuous elements My invention characterized in that the elongated sections of the ment are arranged in an array of juxtaposed relationships. Chronowave field modifier. 4. The length L of the discontinuous element is preferably small enough to prevent arcing. The microwave field modifier according to claim 1, wherein: is 3 cm or less. Fire. 5. The width W of the discrete element is approximately 0.001 inch (0.000254 cm). Claims 1 to 4 are about 1.0 inches (2.54 centimeters) from A microwave field modifier according to any one of the following. 6. Discontinuous elements are approximately 0.0001 inch (0.000254 centimeter) ) to about O. 0.003 inch (0.00762 cm) preferably 0.003 inch (0.00762 cm). 0005 inch (0.00127 centimeter) to 0.002 inch (0.002 inch) 6. The material according to any one of claims 1 to 5, having a thickness of 0.00508 cm). Microwave field modifier included. 7. Discontinuous elements have a resistance of about 100 ohms per square or less. A microwave field modifier according to any one of claims 1 to 6. 8. The surface of the substrate is coated with an undercoating, and the discontinuous elements are Any one of claims 1 to 7 coated with a par coating or both. Microwave field modifier as described in. 9. A microwave field modifier has multiple discrete elements and a second substrate surface arranged in a layer with respect to one discrete element; The discontinuous elongated elements on the surface of the substrate are the same as the elongated elements on the second substrate. Ma is characterized by being at right angles to. The microwave field model according to claim 1. Fire. Any one of claims 1 to 9, wherein ΔT of 10.2 minutes is about 125° or more. The microwave field modifier according to paragraph 1. 11. The discontinuous element has a sufficiently low surface electrical resistance that the element The spacing between the elements is sufficiently small to prevent heating inside the element. The microwave field module according to claim 10, heating a fringe field between Defy. 12. The coating material has sufficiently high insulation loss that all the heating 10. The method of claim 10, wherein the heating is carried out by capacitive heating between electrically conductive particles within the material. Microwave field modifier described in.