Patent Publication Number: US-2023150731-A1

Title: Methods for forming and opening child-resistant reclosable bags

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Application No. 63/279,348, filed Nov. 15, 2021, which is hereby incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     Technical Field 
     The subject matter described herein relates to child-resistant reclosable bags, and more particularly to methods for forming and opening child-resistant reclosable bags. 
     Discussion of Art 
     Child-resistant reclosable bags are used to hold items, such as medicinal capsules, detergent capsules,  cannabis  products, and/or the like. Such items may be attractive, but harmful, to a child. 
     Certain packages include plastic lids, which, in order to be removed from a glass or plastic container, are squeezed or pushed in various ways which may not be apparent to a child, and/or beyond the strength capabilities of the child. However, such containers are complicated to manufacture and add a considerable expense to a finished product. Additionally, such containers may be heavy and bulky, which adds to a cost of transportation. Moreover, the weight and bulk adds to a recycling burden of these products. 
     A known child-resistant reclosable bag includes a seal above locking elements of a two-piece zipper on one zipper half and only below the locking elements on the other zipper half. As such, the bag can be put into a shear mode that is extremely difficult to open when simply pulling the top of the flexible package open as would be done for a typical reclosable flexible package, as described in U.S. Pat. No. 10,118,737, entitled “Child-Resistant Reclosable Bags” (the “737 patent”), which is hereby incorporated by reference in its entirety. Various devices for opening such packages have been developed. For example, the 737 patent describes a complete, but unattached upper flange. As another example, small, graspable tabs are engaged in order to open the closure. 
     Certain known packages include a two-piece zipper closure in a flexible package. Such packages are configured to be opened by exerting a force in relation to the locking elements from below (that is, the product side) the locking elements. Examples of such enclosures are disclosed in the 737 patent, U.S. Pat. No. 10,689,162, entitled “Bag with Zipper Tape,” U.S. Pat. No. 10,427,839, entitled “Resealable Bag,” U.S. Pat. No. 10,099,818, entitled “Reclosable Zipper Having Child Resistant Features,” and United States Patent Application Publication 2018/0273257, entitled “Child Resistant Sealing System.” 
     However, it has been found that packages as disclosed in these references may be too easily opened by simply tugging on flaps and other parts of the bag below the locking elements. 
     BRIEF DESCRIPTION 
     A need exists for a child-resistant reclosable bag that is more difficult for children to open. Further, a need exists for a child-resistant reclosable bag having a smaller area configured to be engaged for opening the bag, in contrast to any location across the width of the bag. 
     With those needs in mind, certain embodiments of the present disclosure provide a child-resistant reclosable bag, including a container configured to retain one or more items within a product portion. A zipper is coupled to the container. The zipper is above the product portion. The zipper includes one or more primary seals, and one or more secondary seals at one or more defined locations. The one or more secondary seals at the one or more defined locations identify opening areas on the product portion. The opening areas are configured to be grasped and pulled apart to open the zipper. In a least one embodiment, the zipper is disposed between the product portion and a consumer portion. 
     In at least one example, the one or more primary seals extend along an entire width of the container, and the one or more secondary seals extend along less than the entire width of the container. 
     In at least one embodiment, the opening areas are below the zipper. In at least one example, at least one of the opening areas is directly below the one or more secondary seals and the one or more primary seals. As a further example, the at least one of the opening area is directly underneath a center of the one or more secondary seals. 
     In at least one example, the opening areas have a first width. The one or more secondary seals have a second width. As a further example, the first width equals the second width. 
     In at least one embodiment, the opening areas include a first opening area on a first face of the container on the product portion, and a second opening area on a second face of the container on the product portion. As an example, the first opening area is directly across from the second opening area. 
     In at least one embodiment, opening indicia designate or otherwise indicate the opening areas. As an example, the one or more secondary seals include the opening indicia. 
     Certain embodiments of the present disclosure provide a method of forming a child-resistant reclosable bag. The method includes coupling a zipper to a container that is configured to retain one or more items within a product portion, wherein the zipper is above the product portion, and wherein the zipper comprises one or more primary seals and one or more secondary seals at one or more defined locations; and identifying, by the one or more secondary seals, opening areas on the product portion, wherein the opening areas are configured to be grasped and pulled apart to open the zipper. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The inventive subject matter may be understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below: 
         FIG.  1    illustrates a lateral view of a child-resistant reclosable bag, according to an embodiment of the present disclosure. 
         FIG.  2    illustrates a cross-sectional view of the child-resistant reclosable bag of  FIG.  1    through line  2 - 2 . 
         FIG.  3    illustrates a cross-sectional view of the child-resistant reclosable bag of  FIG.  2    having opposed forces applied thereto. 
         FIG.  4    illustrates a cross-sectional view of the child-resistant reclosable bag of  FIG.  1    having opposed forces applied thereto. 
         FIG.  5    illustrates a flow chart of a method of opening a child-resistant reclosable bag, according to an embodiment of the present disclosure. 
         FIG.  6    illustrates a flow chart of a method for forming a child-resistant reclosable bag, according to an embodiment of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Certain embodiments of the present disclosure provide a child-resistant reclosable bag that can be devoid of cut zipper tabs. Zipper tabs can be difficult to operate, and typically result in scrap during manufacturing. Moreover, certain embodiments of the present disclosure provide a child-resistant reclosable bag that allows for an opening feature and location to be incorporated during bag fabrication, thereby allowing registration with the pouch, in contrast to a random location of tabs. 
       FIG.  1    illustrates a lateral view of a child-resistant reclosable bag  100 , according to an embodiment of the present disclosure. The bag  100  includes a container  102 , such as a flexible pouch, package, bag, or the like, configured to hold one or more items (not shown) in a product portion  101  below a zipper  110 . In at least one embodiment, the bag  100  is formed of one or more flexible and resilient polymers. 
     The container  102  includes a sealed base  104  at a bottom end  106 , flexible walls  108  extending upwardly from the base  104 , and a top end  109 . A zipper  110  is coupled to the container  102  and is disposed proximate the top end  109 . The zipper  110  is configured to allow the bag  100  to be selectively opened and closed. The zipper  110  includes opposed locking elements  111  on either face of the bag  100  that are configured to selectively mate with one another, as is known. 
     The product portion  101  (for example, an end or side, depending on the orientation of the bag  100 ) is defined below the zipper  110 . A consumer portion  103  (for example, an end or side, depending on the orientation of the bag  100 ) is defined above the zipper  110 . The product portion  101  is configured to retain a product between the zipper  110 , the base  104 , and the flexible walls  108 . 
     The zipper  110  further includes a lower flange  112  below the locking elements  111 , and an upper flange  114  above the locking elements  111 . A primary seal  115  is disposed on the lower flange  112  (lower flange  112   b  in  FIG.  4   ). The primary seal  115  extends across a width  116  of the bag  100 . A secondary seal  118  is disposed on an opposed lower flange  112  (lower flange  112   a  in  FIG.  4   ). The secondary seal  118  is separate and distinct from the primary seal  115 . As shown, the primary seal  115  and the secondary seal  118  can be on one face, such as the face  132  of the bag  100 . Optionally, an opposite face may not include a secondary seal or a primary seal. In at least one embodiment, the primary seal  115  sealingly couples to the face  132  from the lower flange  112 , the secondary seal  118  sealingly couples to the face  132  from the lower flange  112 , and another primary seal couples to an opposite face (such as the face  130  shown in  FIGS.  2 - 4   ) from a lower flange. 
     The secondary seal  118  is located at a defined location  120  of the upper flange  114 . The secondary seal  118  extends along only a portion of the width  116 . For example, the secondary seal  118  is located proximate to a side  122  of the bag  100 . As shown, the secondary seal  118  is offset from the side  122  toward a middle  124  of the upper flange  114 . In at least one embodiment, the secondary seal  118  does not extend to the middle  124  of the upper flange  114 . Instead, the secondary seal  118  is closer to the side  122  of the bag  100  than the middle  124  of the upper flange  114 . 
     In at least one embodiment, the secondary seal  118  is substantially shorter than the primary seal  115 . For example, the secondary seal  118  can be less than half the length of the primary seal  115 . In at least one embodiment, the secondary seal  118  is less than 25% of the length of the primary seal  115 . For example, the secondary seal  118  can be between 5-10% the length of the primary seal  115 . By making the secondary seal  118  substantially shorter than the primary seal  115 , and locating it away from the side  122  and the middle  124 , the likelihood of a child engaging the secondary seal  118  is reduced. 
     As shown, the secondary seal  118  is proximate to the side  122 . Optionally, the secondary seal  118  can be located proximate to the side  126 , which is opposite from the side  122 . 
     In at least one embodiment, the bag  100  includes only one secondary seal  118  at a location that a child may not intuitively grasp. In at least one other embodiment, the bag  100  includes at least one other secondary seal  118 . For example, the bag  100  can include a secondary seal  118  proximate to the side  122 , and a secondary seal  118  at a defined location  120  proximate to the side  126 . As another example, the bag  100  can include three or more secondary seals. 
     The bag  100  is configured to be opened by grasping an opening area  119   a  below the secondary seal  118  on the product portion  101  of the bag  100 . In at least one embodiment, the opening area  119   a  is directly below (or optionally offset from) the secondary seal  118  and the primary seal  115 . For example, the opening area  119   a  can be directly (or optionally, offset) underneath a center  123  of the secondary seal  118  (and optionally, the primary seal  115 ). As an example, the secondary seal  118  has a longitudinal axis  125  extending along a length of the zipper  110  above the primary seal  115 . The opening area  119   a  extends through an axis  127  that is orthogonal (that is, at a right angle) to the longitudinal axis  125 . 
     The opening area  119   a  (and an opening area  119   b , as described herein) can be spaced apart from the primary seal  115 , underneath the secondary seal  118  and the primary seal  115 . For example, the opening area  119   a  can be between 1-3 inches below the primary seal  115 . Optionally, the opening area  119   a  can be less than 1 inch below the primary seal  115 , or greater than 3 inches below the primary seal  115 . 
     In at least one embodiment, the opening area  119   a  is the same width  129  as the secondary seal  118 . Optionally, the opening area  119   a  can have a width that is greater than (for example, 5-10% greater), or less than (for example, 5-10% less than) the width  129  of the secondary seal  118 . 
     As described herein, in order to open the bag  100 , the opening area  119   a  on a face  132  of the bag  100  on the product portion  101  is grasped, and an opening area  119   b  (shown in  FIG.  4   ) is grasped. The opening area  119   b  is directly opposite from the opening area  119   a  on an opposite face  130  of the bag  100  on the product portion  101 . The opening areas  119   a  and  119   b  are grasped and pulled apart from one another, thereby allowing the zipper  110  to be opened. 
     In at least one embodiment, at least one of the opening areas  119   a  and/or  119   b  can be designated by opening indicia  148 . The opening indicia  148  can be or otherwise include a colored region, a shaded region, a text or graphic message, a textured region (such as a roughened, embossed, or the like surface), and/or the like. The indicia  148  denote the area(s)  119   a  and/or  119   b  to be grasped to open the bag  100 . Optionally, the bag  100  may not include the opening indicia  148 . 
     In at least one embodiment, the opening indicia  148  can be on the secondary seal  118 . For example, the opening indicia  148  can be a graphic or text shown on the secondary seal  118  and/or a portion of the container  102  directly secured to the secondary seal  118 . As an example, the opening indicia  148  can be or otherwise include an arrow pointing downward on the secondary seal  118  and/or the container  102 . As another example, the opening indicia  148  can be a message such as “below” or “down” on the secondary seal  118  and/or the container  102 . 
     As described herein, the child-resistant reclosable bag  100  includes the container  102  configured to retain one or more items within the product portion  101 . The zipper  110  is coupled to the container  102 . The zipper  110  is above the product portion  101 . The zipper  110  is disposed between the product portion  101  and the consumer portion  103 . The zipper  110  includes one or more primary seals  115 , and one or more secondary seals  118  at one or more defined locations  120 . The one or more secondary seals  118  at the one or more defined locations  120  identify opening areas  119   a  and  119   b  on the product portion  101 . The opening areas  119   a  and  119   b  are configured to be grasped and pulled apart to open the zipper  110 . 
       FIG.  2    illustrates a cross-sectional view of the child-resistant reclosable bag  100  of  FIG.  1    through line  2 - 2 . In at least one embodiment, the zipper  110  includes the upper flange  114  having a first primary seal  115   a  extending along the face  130 , such as a first face, of the container  102 , and the lower flange  112  having a second primary seal  115   b  extending along the face  130 , such as second face, opposite from the first face  130 , of the container  102 . It is to be understood that the first face  130  may be considered the second face, and the second face  132  may be considered the first face. The terms first and second, for example, are merely to indicate numbers of faces, for example, and are not to limit the identity of the faces, for example. 
     As shown, the opening areas  119   a  and  119   b  are not shown in  FIG.  2   , as the secondary seal  118  (shown in  FIG.  1   ) is not shown in  FIG.  2   . As described, the opening areas  119   a  and  119   b  are located at areas that are aligned with and below the secondary seal  118 . 
       FIG.  3    illustrates a cross-sectional view of the child-resistant reclosable bag  100  of  FIG.  2    having opposed forces F applied thereto. Referring to  FIGS.  2  and  3   , the upper flange  114  can be coupled to just the second face  132  of the container  102 , and the lower flange  112  can be coupled to just the first face  130  of the container  102  (or vice versa). Optionally, the zipper  110  can include an upper flange and a lower flange coupled to both the first face  130  and the second face  132 . As shown, the seal  115   a  extends away from the upper flange  114  and sealingly engages an inner surface  131  of the container  102 . Similarly, the seal  115   b  extends away from the lower flange  112  and sealingly engages an inner surface  133  of the container  102 . As shown in  FIG.  3   , in particular, when the upper ends  140  and  142  of the opposite faces  130  and  132 , respectively, are grasped and pulled with opposed forces F, the bag  100  is forced into a shear mode, making it extremely difficult to pull the closure halves apart. 
     Similarly, if areas below the zipper  110  are grasped and pulled apart with opposed forces F, the bag  100  is also forced into a shear mode, thereby increasing the difficulty in opening the bag  100 . In general, when forces are applied to the bag  100  at the product portion  101  or the consumer portion  103  as shown in  FIG.  3   , the bag  100  becomes skewed into an orientation that results in the locking elements  111  being put into a shear mode, which makes unlocking the opposed locking elements  111  difficult. 
       FIG.  4    illustrates a cross-sectional view of the child-resistant reclosable bag  100  of  FIG.  1    having opposed forces F applied thereto. As shown in  FIG.  4   , the secondary seal  118  extends away from the lower flange  112   a  and sealingly engages an inner surface  135  of the container  102  below the locking elements  111  of the zipper  110 . The secondary seal  118  can be on the second face  132 , or optionally the first face  130 . In at least one other embodiment, a secondary seal  118  can be on the first face  130 , and another secondary seal  118  can be on the second face  132 . 
     In at least one embodiment, the secondary seal  118  is at a height on the container  102  that is at least the same as a top  113  of the locking elements  111 . In at least one embodiment, the secondary seal  118  can be at the same height as a lower portion of the locking elements  111 . In at least one other embodiment, the secondary seal  118  is above the locking elements  111 . 
     The consumer portion  103  extends above the zipper  110 , and the product portion  101  extends below the zipper  110 . The opening area  119   a  is on the face  132 , and the opening area  119   b  is on the face  130 . The opening areas  119   a  and  119   b  are directly across from one another. 
     When the bag  100  is grasped at the opening areas  119   a  and  119   b  underneath the secondary seal  118  and the primary seal  115   a  (such as by fingers of an individual) below the zipper  110 , and a separating force F is applied thereto, the container  102  is put into a typical peel mode, and is able to be opened. Once the opening of the closure is initiated in the opening areas  119   a  and  119   b , the force F can easily be propagated across the entire width of the container  102 , thereby allowing the container  102  to be opened. 
     As such, in order to open the container  102 , an individual first grasps the opening areas  119   a  and  119   b  below the secondary seal  118 . The separating force F is then applied at the opening areas  119   a  and  119   b , which then allows the bag  100  to be opened. 
     In at least one embodiment, the secondary seal  118  and/or the opening areas  119   a  and  119   b  can be coded to indicate their identities. For example, the secondary seal  118  and/or the opening areas  119   a  and/or  119   b  can be color coded. As another example, the secondary seal  118  and/or the opening areas  119   a  and/or  119   b  can be identified with text. As another example, the secondary seal  118  and/or the opening areas  119   a  and/or  119   b  can be identified through a tactile feature, such as a dimple, bump, protuberance, or the like. 
     Referring again to  FIG.  1   , the bag  100  can include indicia  150  for instructions on opening. For example, the indicia  150  can be printed, adhered, or the like to a face  130  and/or  132  of the container  102 . The indicia  150  can be or include text, graphics, or the like that provide instructions for opening the bag  100  (that is, applying the force F at the defined opening areas  119   a  and  119   b  first). 
     As described herein, the bag  100  takes advantage of well understood shear versus peel forces on a two piece zipper enclosure. The bag  100  greatly reduces necessary force applied at an initial opening area (that is, the opening areas  119   a  and  119   b ) in contrast to certain known child-resistant reclosable bags. 
     The opening areas  119   a  and  119   b  below the secondary seal  118  provide the locations for initial engagement of force to open the bag  100 . The opening areas  119  and  119   b  identified by the secondary seal  118  (in particular, the opening areas  119   a  and  119   b  are below the secondary seal  118 ) are locations that are configured to be first engaged to peel open the bag  100  and disengage the opposed locking elements  111  of the zipper  110  from one another. There is no need for cutting tabs to provide such locations. As such, scrap during manufacturing is reduced. The secondary seal  118  can be formed on the container  102  as the container  102  is formed, and easily registered with the container  102 . That is, the secondary seal  118  can be integrally formed with the container  102  as the container  102  is being formed. 
     Referring to  FIGS.  1  and  4   , the secondary seal  118  identifies a localized modified area of the bag  100  where the shear effect is eliminated. The secondary seal  118  is a small, localized seal proximate to the consumer portion  103  of the bag  100 , but which identifies the opening areas  119   a  and  119   b  below the zipper  110  on the product portion  101  of the bag  100 . With the secondary seal  118  in place, the forces F applied below the zipper  110  at the opening areas  119   a  and  119   b  cause the opposed locking elements  111  of the zipper  110  to be put into a peel mode, thereby making the zipper  110  easy to open. 
       FIG.  5    illustrates a flow chart of a method of opening a child-resistant reclosable bag, according to an embodiment of the present disclosure. Referring to  FIGS.  1 - 5   , at  200 , the secondary seal  118  is located on the bag  100 . The secondary seal  118  identifies the opening areas  119   a  and  119   b . For example, the secondary seal  118  can directly identify the opening areas  119   a  and  119   b , such as through the opening indicia  148 , as described above. As another example, the secondary seal  118  can indirectly identify the opening areas  119   a  and  119   b , such as by being at the location above the opening areas  119   a  and  119   b.    
     At  202 , an individual grasps the first opening area  119   a , which is directly below the secondary seal  118  and the primary seal  115 . At  204 , the individual grasps the second opening area  119   b , which is across from the first opening area  119   a . For example, the second opening area  119   b  is on the face  130  directly across from the first opening area  119   a  on the opposite face  132 . At  206 , the individual then pulls apart the first opening area  119   a  from the second opening area  119   b  to open the zipper  110 , and therefore the bag  100 , as described herein. 
       FIG.  6    illustrates a flow chart of a method for forming a child-resistant reclosable bag, according to an embodiment of the present disclosure. The method includes coupling, at  300 , a zipper to a container that is configured to retain one or more items within a product portion, wherein the zipper is above the product portion, and wherein the zipper comprises one or more primary seals and one or more secondary seals at one or more defined locations. The method also includes identifying, at  302 , by the one or more secondary seals, opening areas on the product portion, wherein the opening areas are configured to be grasped and pulled apart to open the zipper. In at least one embodiment, the method also includes designating, by opening indicia, the opening areas. 
     Further, the disclosure comprises examples according to the following clauses: 
     Clause 1. A child-resistant reclosable bag, comprising: 
     a container configured to retain one or more items within a product portion; and 
     a zipper coupled to the container, wherein the zipper is above the product portion, and wherein the zipper comprises:
         one or more primary seals; and   one or more secondary seals at one or more defined locations, wherein the one or more secondary seals at the one or more defined locations identify opening areas on the product portion, and wherein the opening areas are configured to be grasped and pulled apart to open the zipper.       

     Clause 2. The child-resistant reclosable bag of Clause 1, wherein the zipper is disposed between the product portion and a consumer portion. 
     Clause 3. The child-resistant reclosable bag of Clauses 1 or 2, wherein the one or more primary seals extend along an entire width of the container, and wherein the one or more secondary seals extend along less than the entire width of the container. 
     Clause 4. The child-resistant reclosable bag of any of Clauses 1-3, wherein the opening areas are below the zipper. 
     Clause 5. The child-resistant reclosable bag of any of Clauses 1-4, wherein at least one of the opening areas is directly below the one or more secondary seals and the one or more primary seals. 
     Clause 6. The child-resistant reclosable bag of Clause 5, wherein the at least one of the opening area is directly underneath a center of the one or more secondary seals. 
     Clause 7. The child-resistant reclosable bag of any of Clauses 1-6, wherein the opening areas have a first width, wherein the one or more secondary seals have a second width, and wherein the first width equals the second width. 
     Clause 8. The child-resistant reclosable bag of any of Clauses 1-7, wherein the opening areas comprise: 
     a first opening area on a first face of the container on the product portion; and 
     a second opening area on a second face of the container on the product portion. 
     Clause 9. The child-resistant reclosable bag of Clause 8, wherein the first opening area is directly across from the second opening area. 
     Clause 10. The child-resistant reclosable bag of any of Clauses 1-9, further comprising opening indicia that designate the opening areas. 
     Clause 11. The child-resistant reclosable bag of Clause 10, wherein the one or more secondary seals comprise the opening indicia. 
     Clause 12. A method of forming a child-resistant reclosable bag, the method comprising: 
     coupling a zipper to a container that is configured to retain one or more items within a product portion, wherein the zipper is above the product portion, and wherein the zipper comprises one or more primary seals and one or more secondary seals at one or more defined locations; and 
     identifying, by the one or more secondary seals, opening areas on the product portion, wherein the opening areas are configured to be grasped and pulled apart to open the zipper. 
     Clause 13. The method of Clause 12, wherein the zipper is disposed between the product portion and a consumer portion. 
     Clause 14. The method of Clauses 12 or 13, wherein the one or more primary seals extend along an entire width of the container, and wherein the one or more secondary seals extend along less than the entire width of the container. 
     Clause 15. The method of any of Clauses 12-14, wherein the opening areas are below the zipper. 
     Clause 16. The method of any of Clauses 12-15, wherein at least one of the opening areas is directly below the one or more secondary seals and the one or more primary seals. 
     Clause 17. The method of any of Clauses 12-16, wherein the opening areas comprise: 
     a first opening area on a first face of the container on the product portion; and 
     a second opening area on a second face of the container on the product portion. 
     Clause 18. The method of Clause 17, wherein the first opening area is directly across from the second opening area. 
     Clause 19. The method of any of Clauses 12-18, further comprising designating, by opening indicia, the opening areas. 
     Clause 20. A child-resistant reclosable bag, comprising: 
     a container configured to retain one or more items within a product portion; 
     opening indicia that designate opening areas; and 
     a zipper coupled to the container, wherein the zipper is disposed between the product portion and the consumer portion, wherein the zipper is above the product portion, and wherein the zipper comprises:
         one or more primary seals extending along an entire width of the container; and   one or more secondary seals at one or more defined locations, wherein the one or more secondary seals extend along less than the entire width of the container, wherein the one or more secondary seals at the one or more defined locations identify the opening areas below the zipper on the product portion, and wherein the opening areas are configured to be grasped and pulled apart to open the zipper.       

     Clause 21. The child-resistant reclosable bag of claim  21 , wherein the one or more primary seals have a first width, wherein the one or more secondary seals have a second width, and wherein second width is less than the first width. 
     As described herein, embodiments of the present disclosure provide a child-resistant reclosable bag that is not easily opened. Embodiments of the present disclosure provide child-resistant reclosable bags that are less susceptible to being inadvertently opened. Further, embodiments of the present disclosure provide a child-resistant reclosable bags having a smaller area configured to be engaged for opening the bag, in contrast to any location across the width of the bag. 
     The singular forms “a”, “an”, and “the” include plural references unless the context clearly dictates otherwise. “Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description may include instances where the event occurs and instances where it does not. Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it may be related. Accordingly, a value modified by a term or terms, such as “about,” “substantially,” and “approximately,” may be not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged, such ranges may be identified and include all the sub-ranges contained therein unless context or language indicates otherwise. 
     This written description uses examples to disclose the embodiments, including the best mode, and to enable a person of ordinary skill in the art to practice the embodiments, including making and using any devices or systems and performing any incorporated methods. The claims define the patentable scope of the disclosure, and include other examples that occur to those of ordinary skill in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.