DE3835796A1 - FLEXIBLE PACKING FOR MICROWAVE COOKING - Google Patents

Abstract

A food package including a pouch (10) having a microwave interactive component (42) e.g. aluminium. The maximum volume of the foodstuff is less than the internal volume of the pouch and the area of the pouch covered by the microwave interactive component is greater than the area of the foodstuff. The package exhibits particular utility for a frozen pizza to be cooked in a microwave oven. The bottom of the pizza becomes crispened and the cheese is heated, and an airspace above the pizza allows easy removal without cheese sticking to the inside of the pouch. Some residual moisture in the foodstuff may be transformed into steam or hot vapour which further effects uniform heating of the foodstuff. The pouch is formed from a laminate, the laminate defining a unitary blank defined by a flexible generally planar laminate having layers of polyethylene teriphthalate (40), the microwave interactive material, an adhesive (44) and paper (46). Aluminium boil shielding strips (170, 172, Fig 20) may also be present. <IMAGE>

Description

The present invention relates to packaging or pack of food for cooking or boiling with microwaves and in particular a packaging container, in which the food ingested or food to be cooked at least over a partial area when cooking under microwaves browned or crispy is roasted.

Food packs are already known which are used for Immediately cook the food in the microwave oven can be put in there without first the food is removed from the package. Also microwave tanning techniques are already known, where a food product that is in one Microwave oven is to be cooked or cooked in one Pack or a container is given that comes with a microwave interactive material, d. H. one with Microwave interacting material is provided. The microwave interactive material is used during the Exposure to microwave energy in a common Microwave oven hot so that everyone in direct thermal contact with this microwaves interacting material browned food or roasted until crispy. An example of a such a browning or roasting pack is in the US-PS 42 67 420 indicated by Brastad.

The present invention also relates to a Packaging or packaging for food while cooking, boiling or heating in one Microwave oven, this packaging has a thermal Heating effect delivers, as it does when heating up the surface  of the food to a sufficient temperature to cause browning or roasting of the food surface given is. The present The invention is based, such packaging specify where the placement and positioning packaging and food in one Microwave oven are relieved. They should also Materials used more effectively than in the prior art who has similar goals.

The packaging forms possible by the invention are easier to manufacture, require less Manufacturing steps and a shorter production time as numerous well-known packaging for microwave browning and roasting. Particularly crucial is that the packaging forms of the invention enable better cooking and cooking results for many To achieve types of food than has been the case to date available packaging was the case.

The types of packaging possible with the invention, Packs and containers are exceptional suitable for foods with a doughy, not a baked or crusty area like it for pizza, bread items, dessert pies, breaded Portions of fish and, for example, poultry parts in Dough casing is the case. Such food items can usually unsatisfactory in a microwave oven be cooked and boiled, the reason being especially in the absence of thermal heating effects, that in an ordinary cooking environment like in a normal oven.

The packaging or packing according to the invention can the shape of a bag, pouch, envelope or Accept bag or wrapping. All are also other forms explained or implied below  possible. All forms of packaging by the Invention are covered, have an essential Packing area made of flexible composite Material on which is a microwave interactive Component that has the essential property has to convert microwave energy into thermal energy, on the food via heat conduction, Heat convection and / or radiation is transferable. In numerous embodiments of the invention all three types of heat transfer are effective. The flexible composite material that this Heating effect supplies can be of a variety of different types Material components are manufactured. In the preferred embodiments will be flexible Laminate, d. H. a flexible laminate, used the paper and a slightly metallized polyester fiber includes. However, the invention is not limited to that Selection of any specific material for that flexible microwave interactive composite Restricted material. The flexible composite Material or composite material that acts in such a way that it can cause thermal heating effects, the whole Form packaging or the entire container or can also with other flexible materials or in some cases with relatively stiff materials like for example cardboard can be used. In any case is an important aspect of the interpretation of the invention Packaging seen in that area or the area interacting with the microwave Component is covered, is larger than the main area of the food over the area of the mutual contact between the food and the flexible area of packaging that the has microwave-interacting component. It It is important to point out that those with Microwave interacting component not the whole Area of the flexible area of the packaging  must cover, but in any case those of the microwave active component covered area itself always in contact with the area or area extends beyond the food, d. H. these exceeds. The microwave interacting component can instead of being continuously trained in Form of an interrupted pattern, for example in Stripes or dots are present, in such a Case the entire one covered by such a pattern Area contacted by the food Area will exceed.

An important aspect of the interpretation of the Packaging covered by the invention is that the volume of the through the packaging for inclusion of the food defined space in the microwave oven at any time during the microwave cooking process greater than the bulk volume or the filling volume of the food.

These two critical bases of interpretation meet all forms of variation of the invention Packaging for, d. H. all forms or Embodiments become microwave interactive Components that cover an area that is larger than the area of the food that contacted this area of packaging, and all Embodiments become an inner packaging volume have greater than the maximum Filling volume of the ingested food is. The Combination of these design features with usage a flexible material for transmission or Including the microwave interacting component is the basis for the advantages of the invention Packaging versus packaging that with previous concepts and processes were possible. The end result is packaging that is a cooking or  Creates a cooking environment for the food in the microwave oven, which controlled thermal heating effects on the surface of the food product with the accelerated Microwave heating on the inside of the Food products united.

A significant improvement over the previous one Packaging is achieved through the use of a flexible carrier material for microwave interactive Component in combination with the advanced Area of coverage or coverage of the microwave interactive Component over the area or the Area that is in contact with food, reached. The combination of these two packaging features backs up independently and regardless of the exact Shape of the food item a measure of proximity to the microwave-interacting component to the edges or corners of the food item. This will such thermal heating effects created that the Surface quality and structure of the edges and Corners of the food such as those on the ground or on the area that is in direct contact with the microwave-interacting component. Without this measure for the transfer of thermal energy on the edges of the food would be numerous Food items unwanted wet residue or Moisture along these edges or bulges exhibit. The reason for this is that the Edges or corners compared to the area of the Food that is the microwave interactive Material contacted directly, are relatively cold and that Moisture to the colder section of the food wanders. Of course, a complete one Cover the inside of the packaging with microwave-interacting Material an even more comprehensive thermal heating effect for food. A such full containment with interactive component  is particularly in such embodiments important the double-sided roasting or browning effects of the food by turning the packaging over in the middle of the microwave cooking cycle should.

The relationship of the inner volume of the packaging to the maximum main volume or filling volume of the food is required to create a hot air room to create the food around and thereby allowing the food in an environment that cooks or cooks or roasts, the conventional one Cooking conditions (without microwaves) simulated. The types of packaging according to the invention can either be completely closed so that a damp Hot air environment due to the out of food during generated moisture from the cooking process becomes. Alternatively, the packaging or Containers must be partially open to escape to allow for moisture and a relative to create dry hot air environment and upright receive. A hot air room above food is special necessary for such food items, that have a surface that would otherwise be on Would adhere to the packaging, for example for pizza, baguette pizza or frozen pastry products the case is.

The types of packaging according to the invention are complete depending on the use of a flexible Materials for the transport and reception of the microwave-interacting Component. The use of a flexible material in this function allows the most varied Packaging types to irregularly shaped Include food items, and some Agreement of the microwave-interacting component with the surface of the food item  maintain. Furthermore, the invention Packaging forms essentially less material than other relatively rigid types of packaging, whereby the manufacturing costs are lower and lower storage volumes before filling with the food required are. Also, an envelope, a pouch or a bag or a bag that made up are made of a flexible basic material, relatively easy to fill with food be held in the open position. In some Cases can be the material for producing the invention Packaging types suitably in roll form to be delivered to the food packaging center in the final form, for example to bring a bag.

Careful consideration and evaluation of previous ones Packaging forms and concepts clearly show that none of these forms and concepts are the essential ones Elements of the packaging according to the invention combined and their important advantages for microwave cooking from Provide food within the packaging. A number previous patents describe the use of microwave interactive Materials for evoking Surface heating effects in microwave food packaging. In many cases this is microwave interactive Material from a thin in a vacuum deposited metal layer, such as aluminum, or from a polyester film. Are common vacuum metallized films on a rigid carrier material, such as cardboard, for training attached to a free-standing packaging. However, can the packaging does not match the shape of the food be adjusted. Examples of such rigid self-supporting inflexible food packs are in US Pat. No. 4,555,605 (Brown et al), US Pat 45 92 914 (Kuchenbecker), in U.S. Patent 45 94 492  (Maroszek) and in US Pat. No. 4,641,005 (Seiferth). The Maroszek patent is an attempt to get the Limitations of rigid cardboard packaging to clear out about the design of the packaging, the Formation of a cardboard spring is provided to make contact for food either with one or two inner ones Maintain areas of the packaging that the wear vacuum metallized polyester film. Although these Arrangement is apparently reasonably effective this concept cannot dispel the fact that rigid packaging does not conform to the shape of the Food are customizable, especially if the Food item is irregular in shape. Compared to these rigid, self-supporting packaging forms are some of the well-known packaging relatively flexible materials made, the surface heating effects for the food during the Cause microwave cooking. Such flexible packaging are in US Patent 42 67 420 (Brastad), the U.S. Patent 4,553,010 (Bohrer et al) and U.S. Patent 4,641,005 (Seiferth) specified. However, none of these points either proposed flexible packaging the essential Features of the packaging according to the invention. Brastad only proposes packaging that is in In the form of envelopes, which at all points in be in direct contact with the food. On this way is no hot air space around the food present around. As a result, lies in this embodiment no heating effect in relation to the or the food items by convection or Radiation before, causing the assets of this packaging, To provide microwave cooking results which the in conventional cooking method achievable results simulate is restricted. The packaging from Drills are specific as microwave popcorn packs designed and exhibit only a limited  Area at the bottom of the packaging with a microwave converting material is covered, which a surface heating effect for a pop grain layer evokes, the pop grains covering the entire area cover this material. The packaging from Bohrer see therefore no expansion of that of the microwave converting Material covered area over the from the food contact area before, d. H. in this case the area on which the pop grains are placed. Furthermore, the microwave is converting Material in the packaging of drills in all cases on a flat horizontal wall the packaging provided and shows no configuration, which is a match or approximation in terms of the surface of the food and a degree of proximity to the microwave converter Material to the edges of the food item ensures. These points of view in the case are essential to the present invention in these microwave packaging for popcorn not involved. The Seiferth patent includes packaging materials reveals the properties and effects of the packaging materials proposed by Brastad are very similar. As with packaging forms Brastad also lacks this packaging that was already discussed with the Seiferth patent important feature of the hot air space around that Food around, a characteristic that by the Invention is given.

The types of packaging according to the invention are for frozen foods, refrigerated Food and stored at room temperature Suitable for food. Furthermore, this packaging for example in fast food restaurants, in Cafeteria service and similar food serving situations used where a food  is boiled or cooked, is placed in containers and held ready for a period of time before serving and then briefly in a microwave oven reheated before serving. This reheating step can serve the food back to a suitable one for consumption Bring temperature and the desired surface quality to achieve as well as one for color appealing to consumption. Alternatively Reheating can also serve the cooking process or also roasting process for the food items complete that previously before serving have only been partially cooked. In any case the types of packaging according to the invention are ideal for reheating with microwaves because the Cooking environment in the packaging thermal heating effects regarding the surface of the food in Compound with the extraordinarily fast inner Heating of the food by the microwave energy enables. The containers, bags, pouches or envelopes of the packaging according to the invention especially for fast food restaurants, quick and Ready food stores etc. suitable because of relatively low cost of packaging, the universal Suitability of the packaging forms for the Handling the food products and because of the excellent Combination of thermal effects and microwave cooking effects. Offer available packaging not all of these advantages in one type of packaging.

In the following the invention with reference to the drawing explained in more detail. It shows:  

Fig. 1 is a Rohstückvorlage from which a container in the form of a bag is made, from the top,

Fig. 2 is a view showing an intermediate step in the fabrication of the bag from the Rohstückvorlage according to Fig. 1,

Fig. 3 is a similar view as in Fig. 1, which shows the completed bag completely closed,

Fig. 4 is a cross section taken along a line 4-4 in Fig. 1, this view showing the layer composition of the template from which the bag is made,

Fig. 5 is a cross-sectional view showing the package of the invention, while it is in a conventional microwave oven and exposed to microwave energy,

Fig. 6 is a view of a completely sealed container shape of the packaging according to the invention,

Fig. 7, the illustration of an embodiment of a container shape with an open end,

Fig. 8 shows the representation of an embodiment of a container shape with two open ends,

Fig. 9, the representation of an embodiment of a container mold with vent holes,

Fig. 10, the illustration of an embodiment of a container shape having a self-opening seal at one end,

Fig. 11, the illustration of an embodiment of a container shape having a vent hole, which is covered with a self-opening closure cap,

Fig. 12, the illustration of an embodiment of a containment formation with extensive areas at both ends, which serve as carrying handle,

Fig. 13 is a cross-sectional view of an embodiment of a container with two compartments,

Fig. 14 is a sectional view of an embodiment of a container with two compartments, wherein one compartment container is used for expansion and lifting of the Nahrungsmittelgarguts allows over the support surface in the microwave oven,

The appearance if it contains the Nahrungsmittelgargut, can be suspended from a corresponding fastening in the microwave oven Fig. 15 showing another embodiment of a container, the.

Fig. 16 is a cross-sectional view through an embodiment of a container of two interconnected chambers that are semi-vertical cantilevered

Fig. 17 is a cross-sectional view through the embodiment of a container on which a piece of rigid support material is fixed,

Fig. 18 is a cross-sectional view of an embodiment of a packaging, which is partially made of a rigid carrier material,

Fig. 19 shows an inventive container, received in a cardboard box,

Fig. 20, the illustration of an embodiment of a container with a shielding strip of aluminum, which is fixed on the inner side surface of the container,

Fig. 21 is a sectional view through an embodiment in which the microwave interactive component is present as an insert in a layer made of microwave-permeable material bag, and

Shows a material supply roll for the production of inventive packages and the manufacturing steps of the connection of the stock material manufacture. 22 a, food containing package.

In Figs. 1 to 4, reference numeral 10 denotes a normalized one-piece unit Rohstückvorlage from which a container according to the invention and a packaging is made. As shown in Fig. 4, the template is substantially flat and is formed from layers which, starting from one surface of the template to the other, consist of the following materials: polyethylene terephthalate (PET) 40 , a microwave interactive or microwave-interacting Material 42 , which has the property of exhibiting an increase in temperature when exposed to microwave radiation in a conventional microwave oven, an adhesive or adhesive layer 44 and a paper layer 46 . The adhesive layer or layer 44 serves to secure the paper layer 46 to the microwave-interacting material.

A specific set of materials suitable for making the laminate assembly shown in Figure 4 is given below:

• A lightly metallized polyester film, such as that described in US Pat. No. 4,641,005, with a sufficiently thin coating of a metal such as aluminum, for example, to produce the desired interaction with microwave energy in order to produce a surface heating effect for the food. A suitable polyester film is that sold by Mylar or Melinex, which is a biaxially oriented polyester film. In practice, the polyester films can be provided with a vacuum deposition layer made of aluminum such that the optical density of the aluminum-coated film is essentially in the range from 0.15 to 0.30 and that the polyester film thickness is essentially in the range from 1. 27 · 10 ^-5 to 5.08 · 10 ^-5 m. The lightly metallized polyester film of this type provides the combination of layers 40 and 42 in FIG. 4.
• Uncoated bleached white paper, for example paper as is used as uncoated offset paper, with a basis weight in the range of approximately 9.1 to 36 kg per 279 m² can be used. Paper materials up to approximately 20 x 10 ^-5 to 25 x 10 ^-5 m thick have sufficient flexibility as a carrier or base material for the microwave-interacting material of the invention.
• - An adhesive or glue that is a heat resistant Adhesion between the metallized polyester film and the Paper supplies can be made according to the following lamination instructions are produced on a water basis:

Regulation for the production of the adhesive laminate

The combination of the materials described above can be used in a suitable laminate structure using the types of packaging according to the invention a common wet laminating machine or implemented a wet bond laminator will. In such a laminating machine it will be Adhesive either on the paper substrate or the metallized surface of the film or both applied, and then the paper and the metallized film in a printing nip or pair of printing rollers connected, the machine with approximately 60 to 244 m / min runs. A suitable detention or Adhesive application level is usually in the Range from 0.9 to 2.3 kg per 93 m², and a typical A level of approx. 1.4 kg per 93 m² can be achieved with a 110 line  Engraving roller (for partial lamination) applied will. Following this squeezing process under pressure of paper and film with the adhesive or Adhesive layer in between to form a sandwich The laminated, rolled sheet material can be arranged be passed through a hot air curing oven, to harden and solidify the adhesive adhesive to effect. A suitable oven temperature with a material running speed of 91 to 183 m per minute is at approximately 150 to 260 ° C (300 to 500 ° F) lie. Finally, the laminated material in the general rewound, this after passage over a cooling roller after leaving the curing oven is possible.

The special materials and procedures, such as they have been described above represent only possible ones Exemplary embodiments. Other materials can be used and manufacturing methods are used, the Manufacturing process not in all cases on one Shifting process is restricted. It is only supposed to Explanation of a suitable material with an associated one appropriate procedures.

The template 10 is flexible and has individual fields 12 , 14 , 16 , 18 , 30 and 34 . Reference numerals 22 , 24 and 26 denote fold lines or fold seams which extend vertically as can be seen from FIG. 1, while reference numerals 28 and 32 respectively show horizontally extending fold lines. As indicated by the dotting, the field area 18 is provided with a binding agent or adhesive, which is applied on the side opposite the viewer. The PET film 40 ( Fig. 4) is also in Fig. 1 on the opposite side of the viewer and is attached so that it forms the inside of the container or bag. The field 12 can include a transparent plastic strip 36 as a viewing window for the food to be cooked.

FIG. 2 shows an intermediate stage of the manufacturing process for the formation of the container according to the invention, the turning areas or flaps 30 and 34 being bent upwards by 90 °, while the lateral area fields 14 and 16 are straight to the center, ie to the middle field 12 be folded. As shown in Fig indicated 3, is further at a later date. 16 (extending vertically in Fig. 1), the adhesive on the box 18 with a corresponding complementary region of the righthand free edge of the field are connected and fixed thereto to at in this way to form a seam or joint. The adhesive or adhesive on the field 18 is glued along this right-hand or free edge of the field 16 to the PET area, whereupon, as indicated in FIG. 3, the area glued together in this way is bent or folded around the free line 22 .

A suitable adhesive for forming this joint of the illustrated bag must provide good adhesive adhesion both to the paper surface and to the opposite polyester film surface. In addition, this adhesive must have sufficient heat resistance to ensure the safety of the bond even when the packaging materials are heated to temperatures in the range of 204 ° C (400 ° F) due to the conversion of the microwave energy into heat, which is caused by the thin vacuum deposition aluminum layer on the polyester film. The adhesive must also be suitable for use in the packaging of foodstuffs, and must also be capable of being applied with the customary existing equipment used for the use of bags, pouches, envelopes and similar forms of packaging. One adhesive that meets these requirements is AJRFLEX® 421, a self-crosslinking agent in the form of a vinyl acetate-ethylene copolymer water-based adhesive from Air Products and Chemicals, Inc. This adhesive is also suitable for sealing and gluing the folded end portions 30 and 34 of those under consideration Bag.

FIG. 3 shows the complete bag with the regions 30 and 34 completely folded over and glued in in the final method step. As will become clear from the description below, the food to be cooked is put into the bag or pouch before it is completely sealed.

In FIG. 5, reference numeral 10 denotes a turn container according to the invention, the pocket shown therein is placed in the microwave cavity of a conventional microwave oven. The cavity is indicated by the reference number 50 . The reference number 52 denotes a food to be cooked, typically frozen food such as pizza, which has a crust on the bottom and cheese on the top. Reference numeral 54 indicates a space above the food product. The crust or bottom of the food product 52 is in direct thermal contact with the microwave interacting material. During the heating process by the microwave energy in cavity 50 , the microwaves strike the pocket, some of their energy passing through the microwave interacting material (the remaining three elements of the laminate of the pocket are transparent to microwave energy of this frequency). The energy that has passed through hits the food and acts on the food in the usual way of microwave heating. A further portion of the microwave energy generated by the klystron or another generator of the microwave oven is absorbed by the microwave-interacting material, the latter being heated. Since the volume of the pocket or envelope 10 is greater than the volume of the food 52 therein, the space 54 is formed by hot vapors, mostly water vapor. This heated water vapor contributes to the uniform, uniform heating of the food, since it is able to come into surface contact with even the most irregularly existing surface sections of the food. The bottom or bottom portion of food 54 that is in direct thermal contact with the microwave interacting material is browned or roasted because the temperature in this layer 42 rises.

The bag 10 described so far has a layer of microwave-interacting material 42 over its entire surface. In other application examples, however, it may not be necessary for both the main field 12 and the secondary fields 14 and 16 (which ultimately form a different field) to be provided with the interactive material. For example, only field 12 can be provided with this interacting material when the laminate is formed. As will be explained further below, it is not necessary for the interactive material to constitute a continuous layer, but it can also be in the form of strips or, for example, in the form of separate islands.

Various types of packaging that are within the scope of the invention can be sealed to form a closed environment for the food during the microwave cooking process, maximizing the convection heating effect provided by the microwave interactive component, and also the vapor of moisture from the Food is retained within the packaging. Such a completely sealed and closed bag is shown in Fig. 6.

Alternatively, for some types of food products, it may be better for the package to be open to some extent during the microwave cooking process, thereby allowing the moisture contained in the food to escape. For example, the bag may be open at one end during the cooking process ( FIG. 7) or at both ends ( FIG. 8). It is also possible for a bag to have outlet or ventilation openings 60 above the food or along the sides of the bag, as shown in FIG. 9. A pocket can also be produced in which at least a region of the sealing or composite section is produced with an adhesive that softens when heated, this softening taking place in particular due to the heat generated by the microwave-interactive material. In this way, the bag can open spontaneously during the cooking process. A hot melt adhesive suitable for this purpose is an ethylene vinyl acetate hot melt adhesive with a softening point of approximately 93 ° C (200 ° F), such an adhesive providing a self-opening seal of this type. Fig. 10 shows a bag with a seal 70 which is formed in the manner just described. Fig. 11 shows another type of a self-venting package form, in which case a vent opening 80 is covered by a flap or a cutout 82, which is bonded with such an adhesive agent having a low softening point and sealed.

An advantage of the packaging form according to the invention over known packaging forms is the ease of handling when placing in the microwave oven. When removing from the oven after the cooking process and in particular when repositioning and aligning the food in the oven, for example in the middle of a cooking cycle. In general, the packaging forms of the invention have extensive areas, such as the end seals of the bag, which provide a suitable area of attack for lifting, holding and turning over the packaging. If desired, additional handles or tongues can also be attached in the design of a bag, envelope, bag or bag, without deviating from the principle according to the invention. In addition, the area of the packaging that serves to hold the packaging in place can be formed without a microwave-interactive component, so that this area does not heat up and can also be touched at the end of the cooking process. FIG. 12 shows a bag with additional handles 90 and 92 designed in this way at the upper and lower ends of a bag.

Many food products have two of the same type Pages such as waffles or breaded Pieces of fish, these in the middle of the cooking process should be turned around. A bag or pouch with microwave interactive components on both Side of the packaging is for such food products ideal. So a bag type with complete Microwave interactive provided on the inside Component an evenly cooked and roasted breaded Ensure pieces of fish on both sides when in in the middle of the cooking process, turn the bag over becomes. With this approach, every surface of the food in contact with the hot microwave interactive Component layer during half of the Brought cooking. Also every surface of the  Food for the same amount of time in the hot air environment inside exposed to the bag. That way a complete cooking effect not previously possible achieved so far with devices for tanning or roasting food was not possible.

Within the scope of the invention are also types of packaging that have one or more individual chambers or compartments for receiving food. Such a multi-chamber bag can either have individual sections for the same food product in each chamber or can also be designed in such a way that different food items are also accommodated in the different chambers. In the latter case, the different compartments may not all use the same microwave interactive component or include the same level of coverage with microwave interactive components. FIG. 13 shows such a two-chamber bag with two chambers 100 and 102 of the same size.

Such a multi-chamber bag, pouch or casing can also be used to lift the food product beyond the surface of the microwave oven. An example of this is shown in the two-chamber bag shown in FIG. 14, wherein a first chamber 110 is provided which contains a second sealed chamber 112 which inflates due to the heating of the air or the moisture contained therein during the microwave cooking process. Such a two-chamber bag, which lifts the food independently, is placed in the microwave oven in such a way that the first chamber containing the food lies above the inflating second chamber. A controlled amount of water can be added to the swelling chamber to ensure adequate expansion of this chamber, thereby ensuring sufficient lifting of the food containing chamber during the cooking process. The microwave interactive component is provided in such a pocket at least in the chamber containing the food.

Packaging forms within the scope of the invention may have design features that facilitate placement of the packaging with the food contained therein in the oven or other advantages in terms of orienting the packaging and food to a particular position in the oven. For example, a bag, as shown in FIG. 15, can be provided with a partially recessed holder 120 , which allows the packaging with the food contained therein to be hung in a vertical position on a corresponding hook 122 in the microwave oven. A two-chamber pocket with a flexible transition region 130 connecting the two chambers can also be provided. Such a packaging form can be placed in the microwave oven like an inverted "V" ( FIG. 16), the flexible section at the apex of the "V" and the two chambers being in an inclined vertical position.

As already mentioned, the packaging according to the invention is not necessarily flexible overall. Packages with a portion of the package made from a rigid material can use a flexible material for the area of the package that carries the microwave interactive component, incorporating the two important design criteria of the invention. An example of such a packaging is shown in FIG. 17, a pocket 140 of the type already described in detail being fastened on its underside to a piece of cardboard 142 . A heat resistant binding agent, such as the binding agent for the pocket's seams, is used to secure the bag to the cardboard backing. Packaging of this type with an area made of relatively rigid material such as cardboard has several particular advantages. Such a packaging can be used in particular for easily fragile food items, such as frozen pastry molds, which require greater protection than would be provided by an overall flexible packaging. These types of packaging are relatively self-supporting and can be used free-standing and are particularly suitable if no additional outer packaging of any kind is used for the transport of the product on the market. A variation of such a type of packaging is shown in FIG. 18. In this variation, about half of the packaging is made of flexible sheet material 150 containing the interactive component, and about the other half is made of relatively rigid material such as cardboard or cardboard box 152 , the flexible material being in a shape adapted to the food insert or Contour is formed and is connected to the rigid material to form a closed space for the food. As with all other types of packaging of the invention, the area or area covered by the microwave interactive component is larger than the major portion area of the food over the area of mutual contact between the food on the flexible portion of the packaging, and also the volume, that the packaging provides for the reception of the food during the microwave cooking process, larger than the filling volume of the food, these two conditions apply at all times during the cooking process. Thus, the area covered by the interactive component area exceeds also in the embodiment of Fig. 18, the contact surface of the food, and it is also the interior of the package during the cooking process is greater than the area occupied by the diet space.

The bag or envelope according to the invention can also be provided with an external cardboard packaging, for example in the form of a rectangular box for additional packaging. Such an embodiment is shown in FIG. 19, wherein a bag, as already explained, is accommodated in a rectangular cardboard box 160 and carried therein.

In some cases, certain food items require a certain shielding of part of the Food composed of microwave energy with the thermal heating effects from the microwave interactive Component or the components of the Packaging of the present invention will. If necessary, such a shield can be used provided in the types of packaging according to the invention be by placing pieces of aluminum foil inside either the packaging, on its outer surfaces or between layers of packaging used material are provided.

Fig. 20 shows a bag with Aluminiumfolienabschirmstreifen 170 and 172 which are mounted on the inside of the pocket in each case at their edge regions. Here, an adhesive of the type that also serves to seal the composite seams of the bag is used, for example AIRFLEX 421, in order to attach these film strips to the inside of the bag surfaces.

When designing the features according to the invention, it is not necessary to provide the microwave interactive component in the material which forms the overall shape of the packaging. For example, a bag can be made as shown in Fig. 21, the primary structure of this bag being formed from materials that are not microwave interactive materials 180 and an insert or insert 182 of the general composition shown in Fig. 4 be placed in the pocket to provide the required thermal heating effect. In the exemplary embodiment, such an insert is placed on the bottom of the bag.

The packaging forms of the invention are suitable for various methods of inserting this packaging and their use in a packaging process. First of all, can be fully manufactured Packaging, for example in the form of bags or Bags in such a food packaging operation be introduced, with only one end for insertion of the food item is open. In this case can open the end after inserting the food can be closed and sealed or it can the packaging should be left in this open form and, for example, in a box for another Distribution. A second option uses blank templates such as the Standard raw template or standardized template as it continues Was explained in more detail above, with such blank templates introduced into the food packaging process will. With this possibility, the shaping the raw material templates in the final packaging form and placing the food in it in a variety of ways Way, for example the food before it is made any gluing or sealing for training the packaging form is placed on the template.  

In a third possibility, a supply roll from a material such as that described Laminate made of slightly metallized film and paper food packaging. A such a supply roll can be found on a food packaging line run, on this road the rolled material cut, shaped and sealed to create the packaging and the food food in a simple quick Process.

A particularly useful form of a stock roll for use in food packaging is shown in FIG . This supply roll 190 has a suitable heat-resistant adhesive 192 which is printed or applied on the inner surface of the supply material in a pattern which corresponds to the sealing or composite areas of the finished packaging. By applying the adhesive or adhesive in such a pattern to the material, it is possible to avoid the presence of the adhesive on those areas of the packaging that come into contact with the food. The adhesive pattern can be printed on the material by conventional methods and means such as engraving or laminating and flexographic printing. A suitable hot-melt adhesive that can be printed in this way for use on a material supply roll of this type is offered by Roymal, Inc. as product no. 42151 in the form of a heat seal coating (for example heat seal lamination).

Fig. 22 also shows how a single Rohstückvorlage 194, which is cut off from the supply roll, is folded along the center line 196 through the template, wherein the food has been placed on one half of the folded template so 52nd Finally, the bag thus produced is subjected to a heat seal along the folded edges 200 , 202 and 204 , that is to say thermally welded, in order to provide the finished packaging containing the food. The supply roll 190 comprises a laminate of paper and a lightly metallized polyester film, as previously explained.

Claims (11)

1. Standardized blank template for the production of packaging for microwave food, characterized in that the blank template is defined by a flexible, essentially planar laminate, which has layers of ( 1 ) polyethylene / terephthalate (PET), ( 2 ) one from its one surface with microwave-interacting material, ( 3 ) an adhesive and ( 4 ) paper, and that the blank template has adhesive areas and is provided with a plurality of fold lines that allow the template to be folded, in which adhering the adhesive areas to form a container The consequence is that which is designed to receive a food item to be cooked and to be exposed to microwave oven radiation for cooking the food item contained therein. 2. blank template according to claim 1, characterized by that the adhesive areas on the surface of the Polyethylene / terephthalate layer are provided, that are not in contact with the one that interacts with microwaves Layer is. 3. blank template according to claim 2, characterized, that the raw piece template is essentially rectangular and the adhesive areas on peripheral areas the template are provided.   4. blank template according to claim 3, characterized, that a section of the stock template with a strip transparent and flexible plastic material that forms a window, is provided. 5. Container for microwave oven cooking of food, which container is made of a laminate that defines a standardized blank template according to claim 1, characterized in that the template from one surface to the other layers of ( 1 ) polyethylene / terephthalate (PET), ( 2 ) a material which interacts with microwaves, ( 3 ) an adhesive and ( 4 ) paper, that the template has folded fold lines and is provided with mutually adhering peripheral sections to form a substantially flat envelope, that this container has a filling peripheral section which is not so connected so as to form an opening through which a quantity of food can be introduced and that this filling circumferential section is designed in such a way that it can be closed after the quantity of food has been introduced into the container. 6. Container according to claim 5, characterized, that the container is essentially rectangular. 7. Container according to claim 6, characterized, that a section of the container with a strip made of transparent flexible plastic material is.   8. Food pack for food, including a container and food contained therein, which container is made of a flexible, standardized laminate raw material template according to claim 1, characterized in that this template from its one to the other layers of ( 1 ) polyethylene / terephthalate (PET ), ( 2 ) a material which interacts with microwaves, ( 3 ) an adhesive and ( 4 ) paper and that the volume of the food is smaller than the internal volume of the container. 9. Food pack according to claim 8, characterized in that the pack has at least one strip ( 170, 172 ) made of microwave-impermeable material which lies over an area of the food. 10. Food package according to claim 8, characterized in that the package has a stiffening piece ( 142 ) which is attached to one of the outer surfaces of the package. 11. blank template according to claim 1, characterized, that the surface area of that interacting with microwaves Material smaller than the surface area of the other components of the laminate.