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Title:
TACTILE RANCIDITY INDICATOR
Document Type and Number:
WIPO Patent Application WO/2019/027475
Kind Code:
A1
Abstract:
Apparatuses and methods for a tactile rancidity indicator are provided. An example apparatus includes a first sheet, a second sheet, and an adhesive attaching the first sheet to the second sheet. The adhesive may be configured to have a first state when an oxygen level is below a threshold and a second state when the oxygen level is above the threshold. In the second state, the adhesive may further be configured to de-bond, causing the first sheet and the second sheet to change in shape from their shape in the first state.

Inventors:
SJONG ANGELE (US)
Application Number:
PCT/US2017/045587
Publication Date:
February 07, 2019
Filing Date:
August 04, 2017
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
XINOVA LLC (US)
International Classes:
B65D79/02; B32B7/10; B32B7/12; B65D75/52; B65D81/24; C09J11/02
Foreign References:
US20120121874A12012-05-17
US20150002299A12015-01-01
US20070059837A12007-03-15
US20060057022A12006-03-16
Attorney, Agent or Firm:
SPAITH, Jennifer L. et al. (US)
Download PDF:
Claims:
CLAIMS

What is claimed is:

1. An apparatus comprising:

a first sheet;

a second sheet; and

an adhesive attaching the first sheet to the second sheet,

wherein the adhesive is coniigured to have a first state when an oxygen level is below a threshold,

wherein the adhesive is configured to have a second state when the oxygen level is above the threshold,

wherein in the second state, the adhesive is further configured to de-bond, causing the first sheet and the second sheet to change in shape from their shape in the first state.

2. The apparatus of claim 1 , wherein at least one of the first sheet or second sheet has a pre-formed shape, wherein in the second state, the at least one of the first sheet or second sheet changes to the pre-formed shape.

3. The apparatus of claim 1 , wherein the adhesive includes cleavable linkages which cleave upon exposure to reactive oxygen species.

4. The apparatus of claim 1 , wherein the adhesive further comprises a prodegradant sensitive to oxygen.

5. The apparatus of claim 1 , w herein the threshold is an oxygen level of 1% or above.

6. The apparatus of claim 1, wherein the first sheet and the second sheet each respectively have a distal end opposite a proximal end, wherein the first sheet and the second sheet are permanently joined at least one of:

the distal end; the proximal end;

the distal and proximal ends; and

an area between the distal and proximal ends.

7. The apparatus of claim 1, wherein one of the first sheet or second sheet is coupled to an interior surface of a third sheet, wherein in the second state the one of the first sheet or second sheet creates a deformation in the third sheet.

8. The apparatus of claim 7, wherein the deformation of the third sheet produces a perceptible tactile change in an exterior surface of the third sheet.

9. The apparatus of claim 1, wherein one of the first sheet or second sheet is oxygen permeable, allowing oxygen to reach the adhesive.

10. An apparatus comprising:

a container including an interior surface and an exterior surface;

one or more indicators coupled to the interior surface of the container, wherein each of the one or more indicators comprise:

a first sheet;

a second sheet; and

an adhesive attaching the first sheet to the second sheet, wherein the adhesive is configured to have a first state when an oxygen level is below a threshold, and wherein the adhesive is configured to have a second state when the oxygen level is above the threshold;

wherein in the second state, the adhesive is further configured to de- bond, causing the first sheet and the second sheet to change in shape from the first state.

11. The apparatus of claim 10, wherein a plurality of indicators, including the one or more indicators, is distributed over the interior surface of the container.

12. The apparatus of claim 10, wherein the container further includes a defined area, wherein the one or more indicators are located within the defined area of the container.

13. The apparatus of claim 10, wherein at least one of the first sheet or second sheet has a pre-formed shape, wherein in the second state, the at least one of the first sheet or second sheet changes to the pre-formed shape.

14. The apparatus of claim 10, wherein the adhesive is configured to have reactive oxygen species cleavable linkages.

15. The apparatus of claim 10, wherein the adhesive further comprises a prodegradant sensitive to oxygen.

16. The apparatus of claim 10, wherein the threshold is an oxygen level of 1% or above.

17. The apparatus of claim 10, wherein the first sheet and the second sheet each respectively have a distal end opposite a proximal end, wherein the first sheet and the second sheet are permanently joined at least one of:

the distal end;

the proximal end;

the distal and proximal ends; and

an area between the distal and proximal ends.

18. The apparatus of claim 10, w herein in the second state the one of the first sheet or second sheet creates a perceptible tactile change in the exterior surface of the container indicative of the oxygen levels.

19. A method comprising:

monitoring an oxygen level within a container containing a food product using an indicator positioned on an interior surface of the container; and touching a portion of the container proximate to the indicator to assess freshness of the food product.

20. The method of claim 19, wherein touching the portion of the container proximate to the indicator comprises touching a corner of the container.

21. The method of claim 19, wherein touching the portion of the container proximate to the indicator to assess freshness of the food product comprises feeling for deformation of the container proximate to the indicator.

22. The method of claim 19, wherein monitoring the oxygen level within the container comprises using the indicator having an adhesive positioned between two sheets, the adhesive configured to de-bond above a threshold oxygen level.

23. An apparatus comprising:

a first sheet;

a second sheet;

an adhesive attaching the first sheet to the second sheet,

wherein the adhesive is configured to degrade when an oxygen level is above a threshold so that the first sheet releases from the second sheet when the oxygen level is above the threshold.

24. The apparatus of claim 23, wherein at least one of the first sheet or second sheet has a pre-formed shape, wherein when the first sheet is released from the second sheet, the at least one of the first sheet or second sheet is configured to change to the pre-formed shape.

25. The apparatus of claim 23, wherein one of the first sheet or second sheet is coupled to an interior surface of a third sheet, wherein when the first sheet is released from the second sheet, the one of the first sheet or second sheet produces a perceptible tactile change in an exterior surface of the third sheet.

26. An apparatus comprising:

a container having an interior volume;

an indicator located within the interior volume, comprising:

a first member;

a second member; and

an adhesive configured to attach the first member to the second member, wherein the adliesive is configured to degrade when an oxygen level withm the interior volume is greater than a threshold oxygen level and release the first member from the second member,

27. The apparatus of claim 26, wherein at least one of the first member or second member a pre-formed shape, wherein when the oxygen level is greater than the threshold oxygen level, the at least one of the first member or second member is configured to change to the pre-formed shape.

28. The apparatus of claim 26, wherein one of the first member or second member is coupled to an interior surface of the container, wherein when the oxygen level is greater than the threshold oxygen level, the one of the first member or second member produces a perceptible tactile change in an exterior surface of the container.

Description:
TACTILE RANCIDITY INDICATOR

BACKGROUND

[001] Packaged foods may be exposed to various conditions and environments during transit through storage and display on the shelf. Fats in the food are subject to deterioration by rancidity that leads to the formation of objectionable odors and flavors. Oxidative rancidity may occur when oxygen cleaves unsaturated fatty acids at the double bond, resulting in the release of volatile ketones and aldehydes. Hydrolytic rancidity may result from moisture reacting with triglycerides to form fatty acids. Microbial rancidity may be due to the enzymatic (e.g., lipases) breakdown of fatty acids by microorganisms. The degree of rancidifi cation is therefore dependent on the availability of oxygen and moisture within the package.

[002] Efforts to reduce rancidity usually involve placing an oxygen scavenger or sensor in the package. Conventional oxygen sensors typically rely on colorimetric or other visual detection by the consumer. For example, some conventional sensors fluoresce on exposure to oxygen. Such sensors, relying on visual detection, are limited to use with transparent food containers.

S UMMARY

[003] Techniques are generally described that include apparatuses, systems, and methods. An example apparatus includes a first sheet, second sheet, and an adhesive attaching the first sheet to the second sheet. In various examples, the adhesive may be configured to have a first state when an oxygen level is below a threshold, and a second state when the oxygen level is above the threshold. The adhesive may further be configured to de-bond, causing the first sheet and the second sheet to change in shape from their shape in the first state.

[004] In some examples, at least one of the first sheet or second sheet may have a preformed shape, wherein in the second state, the at least one of the first sheet or second sheet changes to the pre-formed shape. The adhesive may include cleavable linkages which cleave upon exposure to reactive oxygen species. In some examples, the adhesive may further include a prodegradant sensitive to oxygen. The threshold is an oxygen level for de-bonding to occur may be 1 % or above. [ΘΘ5] In some examples, the first sheet and the second sheet may each respectively have a distal end opposite a proximate end, wherein the first sheet and the second sheet are permanently joined at least one of the distal end, the proximal end, the distal and proximal end, or an area between the distal and proximal ends. In some further examples, one of the first sheet or second sheet may be coupled to an interior surface of a third sheet, such as that of a container. In th e second state, the one of the first sheet or second sheet may create a deformation in the third sheet. The deformation of the third sheet may produce a perceptible tactile change in an exterior surface of the third sheet. In some examples, one of the first or second sheet may be oxygen permeable, allowing oxygen to reach the adhesive.

[006] In another example, an apparatus may include a container having an interior surface and an exterior surface, and one or more indicators coupled to the interior surface of the container. Each of the one or more indicators may further include a first sheet, a second sheet, and an adhesive attaching the first sheet to the second sheet. In some examples, the adhesive is configured to have a first state when an oxygen level is below a threshold, wherein the adhesive is configured to have a second state when the oxygen level is above the threshold. In the second state, the adhesive is further configured to de-bond, causing the first sheet and the second sheet to change in shape from the first state.

[007] According to some examples, a plurality of indicators, including the one or more indicators, is distributed over the intenor surface of the container. The container may further include a defined area, wherein the one or more indicators are located within the defined area of the container. At least one of the first sheet or second sheet may have a pre-formed shape, wherein in the second state, the at least one of the first sheet or second sheet changes to the pre-formed shape. In some examples, the adhesive may be configured to have reactive oxygen species cleavable linkages. The adhesive may further include a prodegradant sensitive to oxygen. In some examples, the threshold at which the adhesive de-bonds may be an oxygen level of 1% or above. In some examples, the first sheet and the second sheet may each respectively have a distal end opposite a proximate end, wherein the first sheet and the second sheet are permanently joined at least one of, the distal end, the proximal end, the distal and proximal end, or an area between the distal and proximal ends. In the second state, the one of the first sheet or second sheet may create a perceptible tactile change in the exterior surface of the container indicative of the oxygen levels.

[008] An example method for tactile rancidity indication includes monitoring an oxygen level within a container containing a food product using an indicator positioned on an interior surface of the container, and touching a portion of the container proximate to the indicator to assess freshness of the food product.

[009] In some examples, the method may further include touching the portion of the container proximate to the indicator comprises touching a corner of the container. Touching the portion of the container proximate to the indicator to assess freshness of the food product may include feeling for deformation of the container proximate to the indicator. In some examples, monitoring the oxygen level within the container may include using the indicator having an adiiesive positioned between two sheets, the adhesive configured to de-bond above a threshold oxygen level.

[010] In a further example, an apparatus may include a first sheet, a second sheet, and an adhesive attaching the first sheet to the second sheet. The adhesive degrades when an oxygen level is above a threshold so that the first sheet releases from the second sheet when the oxygen level is above the threshold. In yet another aspect, an apparatus is provided including a container having an interior volume, and an indicator located within the interior volume. The indicator may include a first member, a second member, and an adhesive attaching the first member to the second member. The adhesive is configured to degrade when an oxygen level within the interior volume is greater than a threshold oxygen level and release the first member from the second member.

[011] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features wall become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

[012] The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several examples in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings, in which:

[013] FIG. 1 is a perspective view of an indicator;

[014] FIG. 2 is an exploded view illustrating the layers of the indicator;

[015] FIG. 3 is a perspective view of a configuration of the indicator;

[016] FIG. 4 is a perspective view of an alternative configuration of the indicator;

[Θ17] FIG. 5 is a perspective view of a second alternative configuration of the indicator;

[018] FIG. 6 is a front elevation view of a container including one or more indicators; and

[019] FIG. 7 is a sectional view* of a container including one or more indicators,

[020] all arranged in accordance with at least some embodiments of the present disclosure.

DETAILED DESCRIPTION

[021] In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative examples described in the detailed description, drawings, and claims are not meant to be limiting. Other examples may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the Figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are implicitly contemplated herein.

[022] This disclosure is drawn, inter alia, to methods, systems, products, devices, and/or apparatuses generally related to tactile rancidity indicators. For example, a tactile rancidity indicator may be utilized to monitor the condition (e.g., freshness) of a food product i a container holding the food product by monitoring for byproducts of rancidification. If a rancid condition is present, the indicator may readily indicate this externally , through the container, by providing tactile feedback. [Θ23] Examples of tactile rancidity indicators may include a first sheet and a second sheet, and an adhesive attaching the first sheet to the second sheet. The example adhesive may degrade in the presence of oxygen. Thus, in some examples, the adhesive may be configured to have a first state (e.g., bonded) when an oxygen level is below a threshold, and a second state (e.g., de-bonded) when the oxygen level is above the threshold. The threshold may be an ambient oxygen level in a container. When the adhesive is in the second state, the first sheet and the second sheet may change in shape from when the adhesive is in the first state.

[024] FIG. 1 is a perspective view of example indicator 100, according to various embodiments. Generally speaking, FIG. 1 illustrates the various layers of the indicator 100 as assembled. FIG. 2 shows an exploded view of the indicator 100, according to various embodiments. The following description will be made with reference to FIGS. 1 & 2. The indicator 100 includes a first layer 105, an adhesive layer 1 10, and a second layer 115. In various embodiments, each of the first and second layers 105, 115 may have a thin, sheet-like structure. In some embodiments, the indicator 100 may include multiple laminated sheets, the first layer 105 corresponding to a first sheet and the second layer 115 corresponding to a second sheet. In other embodiments, the first and second layers 105, 115 may have a non-flat shape, including, without limitation, a rod- like shape, coiled shape, or other suitable shape. The first layer 105 may correspond to a first member, and the second layer 115 may correspond to a second member. The various components described in FIGS. 1 & 2 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[025] In various embodiments, the first layer 105 may be attached to the second layer

115 via the adhesive layer 110. Thus, each of the first layer 105 and the second layer 115 may be bonded to either side of the adhesive layer 110. In some embodiments, the first layer 105 and second layer 1 15 may, at some points, be permanently bonded together, with or without the presence of the adhesive layer 110. The following description may refer to the first layer 105 and second layer 1 15 as being laminated when they are attached together, and delaminated when the first layer 105 is released from the second layer 115. [Θ26] According to some further embodiments, the first layer 105 and second layer

1 15 may be different portions of a single element. Tn this alternative configuration, the single element may be folded or otherwise attached to itself via an adhesive, such as adhesive layer 110. Accordingly, the first layer 105 may correspond to a first portion of the single element, and the second layer 115 may correspond to a second portion of the single element. Thus, the first and second portions of the single element may be laminated together, and become del animated when the adhesive layer 110 degrades. Thus, when the adhesive layer 110 de-bonds due to oxidative degradation, the first layer 105 may release from the second layer 1 15. In some embodiments, delarnination may include buckling delarnination of the first and second layers 105, 1 15. Buckling occurs when there is a mechanical instability that arises from an elastic mismatch between the two materials that are bonded (e.g., the first and second layers 105, 1 15). The debonding of the adhesive layer 110, plus elastic mismatch between the first and second layers 105, 115 may lead to in-plane compressive stress that drives the buckling delarnination.

[027] In some embodiments, the indicator 100 may have an elongated shape. Each of the first layer 105, adhesive layer 110, and second layer 1 15 may be a sheet like structure, having the same elongated shape and arranged to overlap with one another. The indicator 100 (and correspondingly the first layer 105, adhesive layer 1 10, and second layer 1 15) may, thus, have a proximal end 120 and distal end 125. In other embodiments, the indicator 100 may be configured to have other, alternative shapes, such as a round or elliptical shape, cylindrical shape, rod-like shape, curved or spiral shape, rectangular shape, polygonal shape, or an irregular shape.

[028] In various embodiments, the first layer 105 may be configured to be exposed to the environment of the inside of a container. Accordingly, to allow the adhesive layer 110 to also be exposed to the inside of the container, in some embodiments, the first layer 105 and/or second layer 115 may be oxygen permeable. In other embodiments, the first layer 105 and/or second layer 115 may be coated to mitigate the absorption of oxygen.

[029] The first layer 105 may further be configured to have an original, pre-formed shape. For example, in some embodiments, the first layer 105 may be curled, or otherwise have a shape introduced to it before it is laminated to the second layer 115. Tins may be accomplished by curved extrusion, or introducing residual strain to the first layer 105. When the first layer 105 is laminated, via the adhesive layer 110, to the second layer 1 15, the first layer 105 may be flattened from its pre-formed shape, and made to maintain a flat configuration. In some embodiments, the first layer 105 may be positioned such that, when bonded to the second layer 1 15, the first layer is parallel with the second layer 1 15. When de-bonded from the adhesive layer 1 10, the first layer 105 may return to its pre-formed shape. In some further embodiments, the first layer 105 may, when exposed to oxygen, may undergo a perceptible tactile change, from a first shape to a second shape. For example, the first layer 105 may be flat in its first shape, but when exposed to oxygen, the first layer 105 may become gradually more curved, spiraled, or take the form of another non-flat shape.

[030] In various embodiments, the first layer 105 may be a flexible polymer material.

Suitable materials may include, without limitation, polyethylene (e.g., low-density polyethylene (LDPE)), polypropylene, polystyrene, polyurethane, silicone rubber, or other suitable polymeric material. In further embodiments, the first layer 105 may also be a generally recognized as food-safe (e.g., GRAS) designated material.

[031] In some embodiments, like the first layer 105 and the second layer 115 may be configured to have an original, pre-formed shape. The pre-formed shape of the second layer 115 may be different from the pre-formed shape of the first layer 105, or in other embodiments, the pre-formed shape of the second layer 1 15 may be the same as the pre-formed shape of the first layer.

[032] In some embodiments, the second layer 115 may have a shape introduced to it before it is laminated with the first layer 105. When the second layer 115 and first layer 105 are laminated together, the first and second layers 105, 115 may be made to maintain a flat shape. As described above with respect to the first layer 105, when de- bonded from the adhesive layer 1 10, the second layer 115 may return to its pre-formed shape, or, alternatively, may undergo a change in shape when exposed to oxygen.

[033] In further embodiments, the second layer 115 may be a rigid material relative to the first layer 105. Thus, the second layer 115 may maintain a relatively flat shape even when deiaminated (e.g., released) from the first layer 105. Thus, the second layer 115 may provide a flat substrate to which the first layer 105. By attaching to the relatively rigid second layer 115, the first layer 105 may be made to maintain a flat configuration while laminated to the second layer 1 15.

] As with the first layer 105, the second layer 115 may be a polymer material.

Suitable materials may include, without limitation, polyethylene, polyurethane, silicone rubber, or other suitable polymeric material. In further embodiments, the second layer 115 may also be a GRAS designated material.

] In various embodiments, the adhesive layer 110 may be configured to attach the first layer 105 and the second layer 115. Attachment may include, without limitation, chemical or other suitable bonding. The adhesive layer 1 10 may be an air or oxygen- sensitive adhesive. In some embodiments, the adhesive layer 110 may preferentially absorb oxygen. For example, when ambient oxygen level rise above 1%, the adhesive used in the adhesive layer 110 may begin to de-bond.

] ' Typically, snack bags and other containers are flushed with nitrogen gas prior to sealing to reduce oxygen levels. The oxygen level in snack bags range between 1% and 5%, and varies over time. Expressed as partial pressure (atm), oxygen in the headspace of snack bags may range from 0.05 to 0.21 partial pressure. In some embodiments, ambient oxygen level may refer to an oxygen level in a defined volume in proximity to the indicator 100. For example, the defined volume may be a container in which the indicator 100 is sealed or otherwise enclosed. In some embodiments, the oxygen level may be measured by mass, relative to other gases within the defined volume. In other embodiments, the oxygen level may be measured by volume, or as a partial pressure.] In various embodiments, the adhesive layer 110 may be formulated to begin de- bonding at a desired threshold oxygen level, as required for a particular application. Example threshold oxygen levels may include, without limitation 1%, greater than 1 %, greater than 0.75%, greater than 0.5%, etc.

] In some embodiments, the adhesive layer 110 may include reactive oxygen species (ROS) cleavable linkages. Upon exposure to ROS such as those produced by rancidification, may cause polymers in the adhesive layer 110 to cleave in multiple locations. Example materials with suitable ROS-cleavable linkages may include, without limitation, an ROS-responsive polyiamino thioketal) (PATK). In further embodiments, the adhesive layer 110 may include an oxygen prodegradant, configured to accelerate the degradation of the adhesive when exposed to oxygen. The adhesive layer 110 may be an air-sensitive, food-grade or GRAS composition that contains no oxidants, and instead includes the oxygen prodegradant. For example, the adhesive layer 1 10 may include a transition metal as a prodegradant, including, without limitation, iron or copper.

[039] Accordingly, in various embodiments, the indicator 100 may be used to monitor the rancidity of a food product, and assess the freshness of the food product within a container containing the food product. This may be accomplished by monitoring an ambient oxygen level within the container, as previously described. When the oxygen level exceeds a ihreshold, indicating rancidification of the food product, the indicator 100 may become delammated, causing a perceptible tactile change that may be detected from the exterior of the container. Thus, a consumer or user may identify that the food product has spoiled, or is no longer meets the freshness requirements of a manufacturer or distributor, by touching a portion of the container proximate to the indicator 100.

[040] In such embodiments, the de-bonding rate of the adhesive layer 110 may be adjusted based on the rate of oxidation of a food product to be monitored. For example, in some embodiments, the de-bonding rate may be adj usted to be slightly faster than that of the food product to be monitored so that the indicator predicts rancidification of the food product before (more conservatively) the food product is expected to become rancid. In other embodiments, the de-bonding rate may be adjusted in other ways, such as, without limitation, to match that of the food product to be monitored.

[041] The de-bonding rate may be adjusted in various ways, as will be discussed in further detail below. In various embodiments, the adhesive layer 1 10 may have a cross- sectional thickness less than that of the first layer 105 and/or second layer 1 15. For example, in some embodiments, the adhesive layer 110 may have a cross-sectional thickness that is less than l mm. The thickness of the adhesive layer 115 may be adjusted to adjust the de-bonding rate. In further embodiments, the adhesive layer 110 may be applied to one of the first layer 105, or second layer 115. In further embodiments, the adhesive layer 1 10 may be applied to the first and/or second layer 105, 1 15 in a pattern configured to promote air and/or oxygen diffusion into the adhesive layer 1 10. Thus, the de-bonding rate may be adjusted by changing a pattern, in which the adhesive layer 110 is applied to the first and/or second layer 105, 115. In some embodiments, the de-bonding may further be adjusted by introducing ethylenically unsaturated bonds into the adhesive (e.g., a polymeric adhesive) used in the adhesive layer 110. In yet further embodiments, additional ROS-responsive bonds (e.g., thioketals) may be introduced into a polymeric adhesive used in the adhesive layer 1 10. Although the above techniques have been described individually, it should be understood that one or more of the above techniques may be utilized in isolation or in combination with each of the other techniques.

[Θ42] Oxidative degradation of adhesive bonds is a common failure mode of polymeric adhesives, such as the ones used in adhesive layer 110. The formation of hydroperoxides is a key step in the oxidative degradation of most hydrocarbon polymers. During the induction period of polymer oxidation, the oxygen absorbed by the adhesives causes the quantitative or near quantitative formation of hydroperoxides. The initial oxidation mechanism occurs when a free radical is formed in the polymeric component of an adhesive. Propagation reactions involve the rapid reaction of the polymer free radicals with oxygen-forming peroxy radicals. Accordingly, in some embodiments, the adhesive layer 1 10 may be subject to a thermal cycle prior to use. The thermal cycle eliminates an "oxidative induction time," also known as a latent period that the adhesive may undergo prior to oxidation. In some fuither embodiments, the adhesive layer 110 may further be subject to gamma irradiation prior to use. This may form latent free radicals in polymeric adhesives used in the adhesive layer 1 10, which may, in turn, form peroxy radicals upon exposure to oxygen - further promoting oxidation in the adhesive layer 110.

[043] In various embodiments, the adhesive layer 1 10 may be a G AS, or food-grade material. Suitable materials for the adhesive layer 110 may include, without limitation, polyurethanes, acrylics, hot-melts, starch, vinyl acetate, ethylene, polyvinyl acetate, polyvinyl alcohol, vinylic adhesive, and other suitable polymeric adhesives. In various embodiments, the adhesive layer 110 may be formulated to mitigate or eliminate the presence of antioxidants. Moreover, many GRAS or other food-grade adhesives may be formulated with prodegradants.

[044] In various embodiments, the indicator 100 may be attached to or incorporated within an interior surface of a container. Example containers may include, without limitation, bags, boxes, clamshell containers, and other containers having a wall or surface to which the indicator 100 may be operably attached or integrated with. In some embodiments, the walls of the container may include thin, flexible, laminated film or sheet, such as those found in snack bags for chips, cookies, and other food products. The walls of the container may be flexible and/or thin enough such that the indicator 100 may be tactilely sensed (e.g., felt), by a user or consumer, through walls of the container from the exterior of the container when the indicator 100 undergoes a perceptible tactile change (e.g., the first layer 105 becomes released from the second layer 115). In such embodiments, one of the first or second layers may be attached to an interior surface of the wall of the container via an adhesive resistant to oxidation, heat sealing, or otherwise affixed to the interior surface of the container. To ensure the indicator 100 maintains a desired orientation and position when attached to the interior surface of the container, the first layer 105 and the second layer 115 may be permanently bonded together at a clasp location. For example, the first and second layers 105, 115 may be bonded together using an external clasp at the clasp location, or bonded together using an ultrasonic weld. The indicator 100 may then be attached to the interior surface of the container via the clasp location.

045] In other embodiments, the indicator 100 may not need to be attached to the interior surface of a container, and may instead be located in the intenor of the container. For example, the indicator may be coupled to a seam of a container, such as a sealed bag, or otherwise located within the container to be accessible, by touch, from the exterior of the bag.

Θ46] In yet further embodiments, the container may have relatively rigid walls where the indicator 100 may not be able to felt externally through the walls of the container. In such embodiments, the indicator 100 may be integrated into the walls of the container such that one of the first or second layers 105, 115 may be felt or accessed externally. For example, a defined portion or area of the container may be constructed from a different material through which the indicator 100 may be felt.

047] In some embodiments, a plurality of indicators 100 may be attached to the interior surface of a container. For example, the plurality of indicators 100 may be attached to the interior surface, and distributed throughout the walls of the container. In other embodiments, the plurality of indicators 100 may be located within a defined area of the container. In some embodiments, the plurality of indicators 100 may be attached to the interior of the container near a headspace area of the container, or near a seam where the container is sealed. The plurality of indicators 100 may be arranged such that the plurality of indicators 100 are not able to be tactilely sensed in a first (e.g., laminated) state. For example, in the first state, the plurality of indicators 100 may feel smooth from the exterior of the container. However, in a second (e.g., delaminated) state, once the first layer 105 becomes delaminated from the second layer 115, the plurality of indicators 100 may feel rough from the exterior of the container.

Θ48] In some embodiments, the defined area of the container may be located in at a comer, by a seam, or near the top of the container such that the walls of the container may be collapsed around the indicators 100. In some further embodiments, the defined area may be labeled, color coded, or otherwise indicated on the exterior of the container. Accordingly, by touching the defined area of, a user may be able to quickly ascertain the rancidification or freshness of a food product.

049] The indicator 100 may have a total thickness, T, when the first layer 105 is laminated, via the adhesive layer 110, to the second layer 115. For example, T may be equal to the combined thickness of the first layer 105 when flat, the adhesive layer 110, and second layer 115 when flat. In some embodiments, T may be less than 1mm in thickness. Thus, while the first layer 105 remains laminated to the second layer 115, the indicator 100 may have a T that is not detectable. In contrast, when the first layer 105 becomes released from second layer 115, the indicator may have a total delaminated thickness, Tdel. Tdel may include the combined thickness of the first layer 105 when in a non-flat shape due to the degradation of the adhesive layer 110, and subsequent delamination of the first layer 105 from the second layer 1 15. In various embodiments, the non-flat shape may include the pre-formed shape of the first layer 105, or alternatively, the altered shape of the first layer 105 when exposed to oxygen.

050] Generally speaking, humans are capable of tactilely sensing features as in the micron and sub-millimeter range, and can dynamically detect surface structures may orders of magnitude smaller, for example, in some cases as small as lOnm. The sense of touch is classified as active or passive. It is currently accepted that for static touch (e.g., in the absence of movement or applied vibrations), the minimum feature size that can be detected is around 0.2 mm. Typical container walls, such as those found in snack bags, have a thickness of around 63.5 μηι. Thus, to be tactilely sensed, a structural variation may be introduced to the container wall by the indicator 100. According to various embodiments, structural features introduced by the indicator 100 can be as small as 90 μιη. Thus, when the first layer 105 is released from the second layer 115, the indicator 100 may have a thickness in the range of 90 μηι to 150 μηι. In further embodiments, when in a laminated state, the indicator 100 may not be detectable by touch. Thus, in the first state, the indicator 100 may have a thickness in the range of 10 to 20 μηι. Thus, the indicator 100 may undergo a perceptible tactile change, transitioning from the first (e.g., laminated) state to a second (e.g., deiaminated) state.

[051] FIG. 3 illustrates an example configuration of the indicator 300, according to various embodiments. As previously described with respect to FIGS. 1 & 2, the indicator 300 may include a first layer 305, adhesive layer 310, and second layer 315. The various components described in FIG. 3 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[052] The first layer 305 may be attached to the second layer 315 via the adhesive layer 310. Thus, each of the first layer 305 and the second layer 315 may be bonded to either side of the adhesive layer 310. In the embodiments illustrated, the first and second layers 305, 315 may be permanently bonded at the clasp area 320, located at a proximal end 330. In a first (e.g., laminated) state, the indicator 300 may have a total thickness, T. T may be equal to the sum of the thickness of the first layer 305, t! , the thickness of the second layer 315, t2, and the thickness of the adhesive layer 310, t3. In this first state, the indicator 300 may not be able to be tactilely sensed through the exterior of a container. As the adhesive layer 310 undergoes oxidative degradation, as illustrated in the degraded region 325, the first layer 305 may release from the second layer 315, as depicted at the distal end 335. As a result, the thickness of the indicator 300 in a second (e.g., deiaminated) state is Tdel. In some embodiments, as more of the adhesive layer 310 degrades, the first and second layers 305, 315 may separate further away from each other, increasing Tdel. As Tdel increases, eventually the indicator 300 may become tactilely detectible through an exterior of a container. [Θ53] In some embodiments, as the adhesive layer 310 degrades, the adhesive layer 310 in the degraded region 325 may remain bonded to one of the first layer 305 or second layer 315, resulting in an "adhesive failure." In some embodiments, debonding may occur within the adhesive layer 310 itself, in the degraded region 325. Thus, the adhesive layer 310 in the degraded region 325 may become divided between the first layer 305 and second layer 315, with part of the adhesive layer 310 in the degraded region 325 remaining bonded to the first layer 305 and part of the adhesive layer 310 in the degraded region 325 remaining bonded to the second layer 315. The latter scenario may be considered a "cohesive failure."

[054] In the embodiments depicted, the first and second layers 305, 315 are shown with each having a curved pre-formed shape. Thus, as the first and second layers 305, 315 become delammated, they first and second layers 305, 315 pull further away from each other. This configuration, however, should not be taken as limiting and it should be understood that other pre-formed shapes may be utilized from the first and/or second layers 305, 315.

[055] FIG. 4 illustrates an example alternative configuration of the indicator 400, according to various embodiments. The indicator 400 includes a first layer 405 A, 405B (collectively 405), adhesive layer 410A, 410B (collectively 410), second layer 415A, 415B (collectively 415), and a clasp area 420. The various components described in FIG. 4 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[Θ56] The first layer 405 may be attached to the second layer 415 via the adhesive layer 410. Thus, each of the first layer 405 and the second layer 415 may be bonded to either side of the adhesive layer 410. The clasp area 420 of the indicator 400 may be positioned between the proximal end 430 and distal end 435 of the indicator 400, and the first and second layers 405, 415 may be permanently bonded at the clasp area 420.

[057] On a first side (e.g., proximal end 430) of the clasp area 420, the adhesive layer

410A may begin to degrade at the degraded region 425A. As the first layer 405A and second layer 415A begin to delaminate, the first and second layers 405A, 415A may- separate away from each other.

[058] As previously described with respect to FIG. 3, the first layer 405A and/or second layer 415A may have a pre-formed shape. For example, in the embodiments depicted, the first and second layers 405 A, 415 A are shown with each having a curved pre-formed shape. Similarly, on an opposite side (e.g., distal end 435) of the clasp area 420, the adhesive layer 1 OB may begin to degrade at the degraded region 425B. Accordingly, the structures may be mirrored on both sides of the clasp area 420.

[059] As previously described with respect to FIG. 3, in some embodiments, the adhesive layer 410 in the degraded regions 425 A, 425B may remain bonded to one of the first layer 405 or second layer 415, resulting in an "adhesive failure." In other embodiments, debonding may occur within the adhesive layer 410 itself, in the degraded region 425 A, 425B, with part of the adhesive layer 410 in the degraded region 425 A, 425B remaining bonded to the first layer 405 and part of the adhesive layer 410 in the degraded region 425 remaining bonded to the second layer 415, resulting in a "cohesive failure."

[060] As previously described with respect to the above embodiments, the indicator

400 may not be perceptible by touch while the first and second layers 405, 415 remain laminated. However, as the first and second layers 405, 415 become delaminated, the indicator 400 may undergo a perceptible tactile change, such that the indicator 400 may ¬ be tactilely sensed at one or both of the proximal and distal ends 430, 435.

[061] FIG. 5 illustrates a second example alternative configuration of the indicator

500, according to various embodiments. As in the previous embodiments, the indicator 500 includes a first layer 505, adhesive layer 510, and second layer 515. Here, however, the mdicator 500 includes two clasp areas 520A, 520B (collectively 520). The various components described in FIG. 5 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[062] The first layer 505 may be attached to the second layer 515 via the adhesive layer 510. Thus, each of the first layer 405 and the second layer 515 may be bonded to either side of the adhesive layer 510. A first clasp area 520A is located at the proximal end 530 of the indicator 500, and a second clasp area 520B is located at the distal end 535 of the indicator 500. The first and second layers 405, 415 may be permanently- bonded at the clasp areas 520.

[063] In various embodiments, the adhesive layer 510 may begin to degrade in the degraded region 525, between the two clasp areas 520. When this happens, the first layer 505 and second layer 515 may be released from each other. As previously- described, the first layer 505 and/or second layer 515 may have a pre-formed shape, for example, a curve. In the embodiments depicted, the first layer 505 may have a curve so as to bend in a concave manner when released from the second layer 515. When this happens, the indicator 500 may undergo a perceptible tactile change, such that the indicator 500 may be tactilely sensed between the proximal and distal ends 530, 535.

[064] FIG. 6 is a front elevation view 600 of an example container 605 including a plurality of indicators 625 A-N (collectively 625), according to various embodiments. The container may have an interior volume including a headspace 615 and a food product located in the bottom area 610. The various components described in FIG. 6 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[065] A plurality of indicators 625 may be located within the interior volume of the container 605. For example, in some embodiments, the plurality of indicators 625 may be located in the headspace 615 of the container 605. In further embodiments, the plurality of indicators 625 may be attached to the interior surface of the container 605. As depicted, the plurality of indicators 625 may be located within a defined area 620 of the container 605. The plurality of indicators 625 and/or defined area 620 may be located in the headspace 615 of the container 605. Typically, the headspace 615 of the container 605 is filled with nitrogen gas to slow rancidification and provide cushioning during transport. The food product is typically located at the bottom area 610 of the container 605, depending on the orientation of the container 605.

[066] As previously described, the plurality of indicators 625 may include a first layer, second layer, and adhesive laminating the first and second layers together. When the oxygen level within the interior volume of the container reaches or exceeds a threshold oxygen level, the adhesive may undergo oxidative degradation. As the adhesive de-bonds, the first layer may release from the second layer, allowing the plurality of indicators 625 to be tactilely sensed.

[067] In some embodiments, the plurality of indicators 625 may be arranged such that they feel bumpy and/or rough to the touch. This may be accomplished by adjusting the number of indicators 625, as well as the spacing between each of the indicators 625A- 625N. In further embodiments, the orientation of each of the indicators 625A-625N may also adjusted to create a desired tactile effect. As previously described, each indicator may have a thickness in a first, laminated state that is not detectibie through the exterior of the container 605. When the indicator 625 becomes delaminated, it may then undergo a perceptible tactile change that allows it to be felt through exterior of the container 605. This will be described in further detail below with respect to FIG. 7.

[068] FIG. 7 is a sectional view 700 of a container 705 A, 705B including one or more indicators 725A, 725B, according to various embodiments. The various components described in FIG. 7 are merely examples, and other variations, including eliminating components, combining components, and substituting components are all contemplated.

[069] A first view depicts the headspace 715 A of the container 705A including the pluraiily of indicators 725A in a laminated state. The plurality of indicators 725A is attached to an interior surface 730 of the container 705B. The plurality of indicators 725 A may be arranged in a defined area 720A of the container 705 A. As illustrated, in the laminated state, the plurality of indicators 725A may not be detectibie. In some embodiments, the plurality of indicators 725A in the defined area 720 A of the container 705 A may seem to be smooth from the exterior of the container 705 A. Thus, as previously described, in the laminated state, each of the plurality of indicators 725A may have a total thickness of T.

[070] A second view depicts the headspace 7.15B of the container 705B where the plurality of indicators 725B in a delaminated state. In the delaminated state, each of the plurality of indicators 725B may have a delaminated thickness, Tdel. In the delaminated state, the indicators 725B may be detectibie by touch in the defined area 720B of the container 705B. In some embodiments, the plurality of indicators 725B in the defined area 720B of the container 705B may seem rough to the touch, from the exterior of the container 705B.

[071] Accordingly, in some embodiments, the plurality of indicators 725B may create a deformation in the container 705B that may be tactileiy sensed from the exterior surface 735 of the container 705B when the first and second lay ers of the plurality of indicators 725B become delaminated. This deformation of the walls of the container 705B can be seen in the defined area 720B, and may create a perceptible tactile change in the container 705B that may be felt from the exterior of the container 705B. [Θ72] The present disclosure is not to be limited in terms of the particular examples described in this application, which are intended as illustrations of various aspects. Many modifications and examples can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and examples are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds compositions or biological systems, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular examples only, and is not intended to be limiting.

[073] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

[074] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g. , bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term 'includes" should be interpreted as "includes but is not limited to," etc.).

[075] It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim recitation to examples containing only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., '"a" and/or '"an" should be interpreted to mean "at least one" or "one or more"); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations).

Θ76] Furthermore, in those instances where a convention analogous to "at least one of

A, B, and C, etc." is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g. , "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A,

B, or C, etc." is used, in general, such a constmction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of

A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and

B. "

077] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any indi vidual member or subgroup of members of the Markush group.

078] As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non- limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as "up to," '"at least," "greater than," "less than," and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 items refers to groups having 1, 2, or 3 items. Similarly, a group having 1-5 items refers to groups having 1, 2, 3, 4, or 5 items, and so forth.

[079] While the foregoing detailed description has set forth various examples of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples, such block diagrams, flowcharts, and/or examples contain one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples can be implemented, individually and/or collectively, by a wide range of components, or any combination thereof.

[08Θ] Those skilled in the art will recognize that it is common within the art to describe devices and/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes. That is, at least a portion of the devices and/or processes described herein can be integrated into other types of packaging and containers for products including those other than food products, via a reasonable amount of experimentation.

[081] The herein described subject matter sometimes illustrates different components contained within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as "associated with" each other such that the desired functionality is achieved, irrespecti ve of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being "operably connected", or "operably coupled", to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being "operably couplable", to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wireiessly interacting components and/or logically interacting and/or logically interactable components,

] While various aspects and examples have been disclosed herein, other aspects and examples will be apparent to those skilled in the art. The various aspects and examples disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.