WO2009090674A2

WO2009090674A2 - Auto venting packages

Info

Publication number: WO2009090674A2
Application number: PCT/IN2009/000048
Authority: WO
Inventors: Ashok Chaturvedi
Original assignee: Ashok Chaturvedi
Priority date: 2008-01-17
Filing date: 2009-01-19
Publication date: 2009-07-23
Also published as: WO2009090674A3

Abstract

The present invention relates to auto venting packages with controlled venting through an unsealed passage (C1,C2,C3) generated within the sealed band(s) on the package. Such packages providing auto venting are well suited and safe for efficient microwave cooking or reheating. They offer fast microwave cooking compared to open cooking & have advantages of additional effect of steam cooking which also keeps the food well hydrated with minimal loss of nutrients. There is no need to add water also. Besides this, the packages with venting can also be used for packing & storing items like pet foods etc. which need venting to remove gases generated & to avoid ballooning when taken in low pressure areas like high altitudes.

Description

AUTO VENTING PACKAGES

Field of the Invention :

The present invention relates to auto venting packages with controlled venting through an unsealed passage generated within the sealed band(s) on the package. Such packages providing auto venting are well suited and safe for efficient microwave cooking or reheating.

Background of the invention ; Microwave energy is used widely for cooking or reheating food products kept in special microwave compatible containers. Such items are available in pre-packed condition also. The packed packages are suitable for microwave cooking or reheating and should have safe and controlled venting for proper cooking or reheating.

Whenever food product in a film or laminated package is heated in a microwave oven for cooking or reheating, the vapors are generated from the product causing ballooning of the package, this increased pressure inside the package may burst open the package and the product may get destroyed and scattered/ splashed inside the oven. In order to overcome this, passage(s) providing controlled venting is an option to allow escape of the vapors generated from the food product inside the package because of heating. The instant invention discloses controlled auto venting packages for achieving these purposes.

Object and summary of the invention :

This invention is related to the development of film or laminate package used for food packaging, cooking or re-heating in a microwave oven with auto controlled venting of air, vapor or gas. The designs of these packages can be used to store and carry food products for human, pets and for. animals, which need to have provision of venting to release the excess air, vapor or any gas generated in side the package. In this invention, an unsealed passage is created in the sealed band at the edge(s), within the two film or laminate walls participating in the seal. This unsealed channel or passage acts as an auto controlled vent for the escape of air, vapors or gas from the inside of the package after certain pressure is developed inside the package.

The unsealed passage(s) can also be created by sealing a fold in the front or back wall with channel(s) opening inside of the package on one end & to the atmosphere on the other end.

In another embodiment of the present invention, the front or back wall of the package is sealed with a separate narrow strip of polymer laminate, which leaves an unsealed area in the sealed band and creates a passage for venting the excess air, vapors or gas from the package. The laminated strip has different polymer layers, where one side of the strip has a heat seal able polymer which seals with the inside surface of the front or back wall of the package. The other side of the strip has non seal able polymer which does not seal with the , inside of the front or back wall of the package even in the sealed band at the edges. So an unsealed area is left at both the ends of the laminated strip. The unsealed area creates a passage for controlled escape of air, vapors or gas from the package.

Brief description of the accompanying drawings : The invention, together with its objects and advantages may be best understood with reference to the following description taken in conjunction with the accompanying drawings.

Figure 1 shows the front view of a three side gusseted package with an unsealed area in the shape of a channel created within one of the side gusset sealed area of the package. Figure 2 shows the front view of a three side gusseted package with an unsealed area in the shape of a channel created within sealed area on two side gussets of the package.

Figure 3 shows the front view of a three side gusseted package with an unsealed area in the shape of a channel created within sealed area on two side gussets as well as at bottom gusset sealed area. The channel can also have perforations in front &/or back wall of package. Figure 4 shows front & side views of zipper and slider assembly for re-closing and reopening of the package, with & without diaphragm.

Figure 5 shows the side views of "close by hand pressing & open by pulling" type zipper assembly for re-closing and re-opening of the package, with & without diaphragm. Figure 6 shows the sealed and unsealed sides of the narrow laminated polymer strip, with the front and back wall of the package with the zipper & slider assembly for re-closing and re-opening of the package.

Figure 7 shows the sealed and unsealed sides of the narrow laminated polymer strip with the front and back wall of the package with "close by hand pressing & open by pulling" type zipper assembly for re-closing and re- opening of the package.

Figure 8 shows the unsealed channels created within the sealed fold in the front or back wall of the package.

Detailed description of the invention : The auto venting microwave able packages have variety of advantages for food cooking or reheating. The controlled venting feature enables the packages to release excess steam from the package without bursting the package when cooking or reheating in the microwave oven. Additionally, if the food product is cooked or reheated, the water content of the product is lost in the form of steam making the food product dry which does not feel good while eating & also looses it's aroma resulting in poor taste. Whereas in case of product cooked or reheated in package with auto venting, the steam trapped inside the package keeps the product well hydrated with minimal loss of nutrients. Presence of steam also provides additional cooking effect from outside the product. This significantly reduces the cooking time also. The package with auto & controlled venting can go directly from the freezer or the refrigerator to the microwave oven.

In another application, some packages used to store and carry food products for human, pets and for animals, need to have provision of venting to release the excess air, vapor or any gas generated in side the package. If the package does not allow release of excess air, vapor or any gas, the package shows ballooning which may cause bursting & also becomes more voluminous. To overcome such problems, venting passage(s) in the package is a practical solution.

The instant application covers, packages of any design like gusseted package, stand up package or any other shaped packages, meant for single use or reuse for storage or for microwave cooking or reheating. Unsealed area in the shape of a channel(s) is created within the sealed surface(s) of the package to release the excess air, vapor or any gas to avoid bursting.

In another aspect of the present invention, a separate laminated narrow polymer strip with one non heat seal able surface & the other with heat seal able layer is sealed with the inside of the front wall or back wall of the package. The other surface of the laminated strip being non sealable does not seal with the inner surface of the other wall of the package. The non sealable surface of the strip leaves unsealed passage across the width of the package's side seal on both the ends. The air, vapor or any gas can come out through this opening after sufficient pressure is buildup inside the package. The required level of pressure inside the package may be designed by varying the opening size of the side seals by varying the strip width. The auto venting may be controlled by varying the shape, size and number of said sealed fold, channels or gates to allow the venting based on the validated pressure inside the package.

The package mouth is provided with either fixed closing or with re-closable and re-open able means. The re-closable and re-open able feature on the package mouth is achieved by providing a set of zipper made of suitable polymer is operated by a slider lock made out of suitable polymer or the zipper can be locked by hand press and opened by pulling the male and female tracks apart where no slider lock is required. The zipper can be sealed on it's flaps with a diaphragm ' 16', if the bags are required to have temper proof evidence.

In this kind of package there is a front and back wall, which can be joined together by direct heat sealing or ultrasonic sealing or any other means, with each other at the edges of the walls or the front and back walls can be joined together by sealing with separate gussets on both the sides and at the bottom of the package. The sealing of the side gussets and the bottom gussets provide the package with more space, easy storing and convenience of standing up the package.

The package top end is for taking out the product from the package which is either permanently closed or attached with re-closable and re-open able means.

For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless, be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated package and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.

The film or laminate vented package can be re-closable and re-open able when the packages need to be reused. For re-closing and re-opening of the package, a set of male and female zipper is sealed on the inside or on the outside surface of the front and back walls of the package. The male and female tracks of the zipper can be closed by hand pressing or by assembling with a separate slider lock over the male & female tracks of the zipper. The package can be attached with temper proof evidence like polymer diaphragm at the open able end of the package, when the package is pre packed with food items for direct sale and use thereafter.

Figure 1 shows the front view of a three side gusseted package. An unsealed channel is created within the sealed area, shown as 'Cl' in the drawing. The two side gussets are shown as '2' and '3', sealed separately with the front wall 'Ia' and with the back wall ' Ib'. The bottom gusset '4' is also sealed separately with the front and the back wall of the package. The zipper male-female tracks assembly is marked as '5' which enables re-closing and reopening of the package mouth. The zipper can be of either "close by hand pressing & open by pulling" type or can have slider lock to close and open the zipper, marked as '6' in the drawing. The same principle of venting can be adopted in packages without gussets or standup packages.

Figure 2 shows the front view of a three side gusseted package. Two unsealed areas in the shape of channels, marked as 'Cl' and 'C2' are created in the sealed band of both the side gussets, between the two film or laminate walls participating in the seal. These channels allow controlled release of excess air, vapors or gas from the package. The vapors or gas are generated as a result of microwave cooking or reheating or released from pet or human food stored in the packages. The size & numbers of these venting channels on various sealed edges of the package depend on the package size, purpose and type of food content in side the package.

Figure 3 shows the front view of a three side gusseted package with an unsealed area in the shape of a channel created within sealed area on two side gussets marked as 'Cl', 'C2' & on bottom gusset sealed area marked as 'C3', to release the excess air, vapors or gas.

As shown in the figure 3 the unsealed channel for controlled venting can have perforation(s) as marked '7', in front &/or back wall of the package, passing through the channel in the sealed area. In Example 'II' the vapors flow to the channel(s) and escape through perforation(s) made on the film or laminate wall(s). The perforation can be single or multiple depending upon the bag size, purpose and type of food content in side the package. In case of packages for microwave cooking or reheating, the number & size of channels or number & size of perforations depends on the desired pressure to be maintained inside the package before the release starts from the vents.

Figure 4 Shows the zipper and slider assembly for re-closing and re-opening of the package mouth. The zipper male track '8' and female track '9' are made from suitable polymer which can be sealed, stitched, ultrasonic welded or joined by any other suitable technique, with front and back wall surfaces, shown as '10' in the drawing. The slider is designed to lock and open the male & female tracks of the zipper assembly by sliding along the length of the zipper. The zipper can be provided with diaphragm '16' of film or laminate to act as temper proof evidence, as shown.

Figure 5 shows "close by hand pressing & open by pulling" type zipper for re-closing and re-opening of the package mouth. The zipper male track '11' and female track '12' are made from suitable polymer which can be locked together by manual pressing and can be opened by pulling apart the male & female tracks. The zipper with male & female tracks can be sealed, stitched, ultrasonic welded or joined by any other suitable technique, shown as '10' in the drawing. The zipper can be provided with diaphragm '16' of film or laminate to act as temper evidence, as shown.

Figure 6 shows another embodiment of this invention wherein a narrow laminated film strip is sealed inside the front or back wall 'Ia / Ib'. The outer layers of the polymer laminate strip are made of two different polymers, as shown in the drawing. One layer, shown as '13' is of sealable polymer(s) which seals with the inside surface of the front or back wall 'la/lb' of the package, as shown in the drawing. The other side of the laminate strip '14' is of non sealable polymer(s) which does not seal with the inside surface of the front or back wall 'la/lb' of the package. Because of the two different characteristic of two sides of this laminate strip, a passage as unsealed area '15' is left when this strip is sealed between the front & back walls ' Ia & Ib'. The zipper with male and female tracks are sealed with inside or outside of the front and back walls of the package, shown as ' 10' in the figure. The slider lock '6' is assembled over the male and female tracks of the zipper for re-closing and re-opening of the package mouth.

Figure 7 shows the sealing of the narrow laminate strip, as explained for Figure 6 but with a package provided with "close by hand pressing & open by pulling" type zipper.

Figure 8 shows a fold created in the front or back wall (la/lb) on the package surface.

The fold is sealed at '18' using a sealing dies, leaving some unsealed area in the form of channel(s) '19'. The sealed fold can be bent upwards or downwards, as shown in the figure, to remain parallel to the package wall. The channel branches, shown as '20' in the figure, open inside of the package as one or multiple narrow gate(s). The other end(s) of the channel opens to the atmosphere shown as '21'. The air, vapors or gas inside the package flow through the narrow gate(s) to the channel opening outside at '21 '. The indirect & restricted flow offers controlled release of air, vapors or gas. The male-female tracks assembly of zipper is marked as '5' which enables re-closing and re-opening of the package mouth. The zipper can be of either "close by hand pressing & open by pulling" type or can have slider lock to close and open the zipper.

It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the invention and are not intended to be restrictive thereof.

Claims

I claim

1. A controlled auto venting package comprising of at least one sealed band having means for venting excess air/gas/steam/pressure beyond a validated pressure from the package, said venting means being an unsealed passage(s) within the film or laminate walls of the said sealed band(s).

2. A controlled auto venting package as claimed in claim 1 wherein said unsealed passage(s) have one or more perforations in the front and/or back wall in the said sealed band(s) of the package.

3. A controlled auto venting package as claimed in claim 1 wherein said validated pressure is set by varying the shape, number, width and length of the unsealed passage(s) based on the package size, purpose and content.

4. A controlled auto venting package as claimed in claim 1 wherein said unsealed passage(s) is created by specially designed band sealing tools to leave the sealing band unsealed at the desired location(s).

5. A controlled auto venting package as claimed in claim 1 wherein said package is microwavable and heat stable.

6. A controlled auto venting package as claimed in claim 1 wherein said package is selected from a gusseted package, stand-up package, single use package, re-usable package, re-closable & re-openable package or permanently closed package.

7. A controlled auto venting package as claimed in claim 1 wherein said package further comprises a re-closable & re-open able means, said re-closable & re- openable means being a zipper made of a suitable polymer(s) lockable with a slider lock or by hand-pressing.

8. A controlled auto venting package as claimed in claim 1 wherein said package is used for food packaging, steaming, cooking, reheating, microwave cooking or storage of food products.

9. A controlled auto venting package comprising of at least one sealed band having means for venting excess air/gas/steam/pressure beyond a validated pressure from the package, said venting means being unsealed passage(s) created by sandwiching a polymer laminate strip(s) having one heat sealable surface and other side surface being non heat sealable, inside at least one of the sealed band(s).

10. A controlled auto venting package as claimed in claim 9 wherein said validated pressure is set by varying the shape, size and number of unsealed passage(s).

11. A controlled auto venting package as claimed in claim 9 wherein said package is microwavable and heat stable.

12. A controlled auto venting package as claimed in claim 9 wherein said package is selected from a gusseted package, stand-up package, single use package, re-usable package, re-closable & re-openable package or permanently closed package.

13. A controlled auto venting package as claimed in claim 9 wherein said package further comprises a re-closable & re-open able means, said re-closable & re- openable means being a zipper made of a suitable polymer(s) lockable with a slider lock or by hand-pressing.

14. A controlled auto venting package as claimed in claim 9 wherein said package is used for food packaging, steaming, cooking, reheating, microwave cooking or storage of food products.

15. A controlled auto venting package comprising of at least two walls having means for venting excess air/gas/steam/pressure beyond a validated pressure from the package, said venting means being a sealed fold(s) in at least one wall of said package wherein said sealed fold opens inside the package at one end and to the outside atmosphere at the other end indirectly in a restricted manner.

16. A controlled auto venting package as claimed in claim 15 wherein said sealed fold is partially sealed to create unsealed channel(s) which connect to the outside atmosphere and inside of the package indirectly.

17. A controlled auto venting package as claimed in claim 16 wherein said channel(s) have branches which open inside the package as one or more gate(s).

18. A controlled auto venting package as claimed in claim 15 wherein said validated pressure is set by varying the shape, size and number of said sealed fold, channels or gates.

19. A controlled auto venting package as claimed in claim 15 wherein said package is microwavable and heat stable.

20. A controlled auto venting package as claimed in claim 15 wherein said package is selected from a gusseted package, stand-up package, single use package, re-usable package, re-closable & re-openable package or permanently closed package.

21. A controlled auto venting package as claimed in claim 15 wherein said package further comprises a re-closable & re-open able means, said re-closable & re- openable means being a zipper made of a suitable polymer(s) lockable with a slider lock or by hand-pressing.

22. A controlled auto venting package as claimed in claim 15 wherein said package is used for food packaging, steaming, cooking, reheating, microwave cooking or storage of food products.