1) Field of the Invention
The present invention relates to a surface such as a beverage cup, bottles, paper labels, appliance surfaces, bowls, containers, pipe, and the like, having improved insulation properties, reduced condensation and improved tactile feel.
2) Description of Related Art
For beverage container such as coffee cups and the like, the beverage is typically served at temperatures in excess of 160° F. and even in excess of 185° F. Even brief exposure to these temperatures can cause significant scalding. The risk of scalding is increased with hot beverages when served in paper or plastic disposable cups. The paper or plastic must be kept thin to reduce cost, weight, and the height or volume of a stack of cups.
Attempts have been made to balance the thinning of the paper or plastic of the cup materials with the need to protect from scalding such as U.S. Pat. No. 5,222,656 directed to a sleeve for insulating the hand while holding a beverage cup. A tubular body of felt-like material conforms by a press fit relationship with the sidewall of a beverage cup when the beverage cup is inserted into the sleeve through the first end of the body. U.S. Pat. No. 5,579,949 is directed to a “C” shaped sleeve for insulating the hand while holding a beverage cup. A plastic molded shape having two broadened ends connected by a thinner central strip form a “C” that is sized to be slightly under the diameter of a conventional hot beverage cup and to snap onto the sidewall of the beverage cup and hold in a spring like fashion. U.S. Pat. No. 5,667,135 is directed to “honeycombed” insulation sleeve disposed around a beverage cup. U.S. Pat. No. 5,454,484 is directed to paper sleeve, stored in folded configuration, and expanded for receiving a cup.
There is also disadvantages of placing cold liquids in “thin” containers in that temperature differences between the beverage container outer wall, ambient temperature, and moisture levels can cause condensation on the outer wall of the beverage container. Such containers include paper or plastic cups, ice cream containers, and ice trays just to name a few. Previous attempts to reduce or eliminate the effect of condensation on such a surface have been tried. Condensation on the surface, such as a beverage container, bowl and the like, can damage supporting surfaces such as table tops an counter tops. Additionally, condensation on a surface can reduce the ability to securely hold the surface such as with a beverage container becoming “slick”. Additionally, condensation on the surface can cause the underlying structure to degrade. The well-known effect of condensation on paper cups where the condensation breaks down the structural integrity of the beverage container is one example.
Such attempts to manage condensation include U.S. Pat. No. 1,910,139 directed to a liquid absorbing pad placed on supporting surfaces such as under glasses, pitchers and other receptacles whereby the condensation which forms and accumulates on the outside of the receptacles when used for serving cold beverages may be absorbed and prevented from wetting the supporting surfaces. Other coasters are described in U.S. Pat. Nos. 2,014,268; 1,959,134, 2,215,633, and 2,595,961. Much effort has been directed to the management of condensation and not necessarily to the prevention of condensation on these paper or plastic beverage cup, especially those with thinner walls and especially for disposable beverage containers.
Additionally, for beverage containers used with cold liquids, condensation can be reduced by using insulating rubber or foam sleeves. However, these solutions are expensive and add additional weight. Much attention should be spent on reducing heat transfer, scalding, and condensation on thin, disposable paper or plastic cups.
By way to example and not limitation, the beverage container will be used in the application to illustrate the invention. The invention can apply as well to a surface that is used for ice trays, bottles, paper or plastic cups, ice cream containers, ice containers, coolers, pipe, mechanical parts, electrical parts, durable goods, and other such articles that can use the benefits of the present invention to improve the insulation against heat and prevent condensation that occurs due to the temperature differential in proximity to the surface.
Accordingly, it is an object of the present invention to provide a beverage container that provides improved insulation properties for hot liquids and reduces condensation for cold liquids.
It is another object of the present invention to provide a beverage container that reduces or eliminates the need for cup sleeves and coasters, or that allow the sleeve to be thinner and lighter weight.
It is another object of the present invention to provide improved insulating ability of thin surfaces to control heat transfer from the surface to an object touching the surface or to improve resistance to condensation of liquids from a humid atmosphere.
It is another object of the present invention to reduce the sensation of heat and to protect the hand from scalding without the need for an insulating glove, a second cup used over the inner cup, a paper sleeve or corrugated paper for a cardboard second layer or sleeve to prevent additional cost, weight, and thickness.
The above objectives are accomplished according to the present invention by providing a micro-structure that can include micro-features or a patterned micro-surface of a particular design to control heat transfer between the cup surface and the external environment. A notable aspect of the design of the patterned micro-surface is the use of high aspect ratio features that are taller than they are wide. The micro-features provide for a decrease in condensation on the outer wall of the beverage container containing a cold liquid. The decrease in condensation includes decreased condensation or humidity on a container containing a cold liquid and that do not leave condensation on a surface below the container after 25 minutes in a humid environment.
The micro-features on a surface can reduce heat transfer between a surface made from rubber, paper, metal, plastic, glass, ceramic, or any combination thereof. The surface can be manufactured by injection molding, compression molding, lamination, embossing, stamping, sintering, additive manufacturing, milling, electrical discharge machining, casting, laser engraving, or by printing processes including ink jet processes, roll to roll contact print processes, intaglio printing, cast and cure transfer printing and similar printing processes. The micro-features can be made by printing ink on paper using inks that form three dimensional structures and include methods such as ink jet printing, thermal printing, additive manufacturing, and the like. The micro-features can be formed by the use of expandable materials which expand into a mold to form or impart features into the expandable material. The microfeatures can be applied to a material surface where multiple microfeatured surfaces can be brought together in successive steps whether of the same or multiple materials to make a combined micro surface the achieves the same performance or instances where the microfeatures can be placed on both sides of the material to achieve an additive benefit.
The micro-features themselves can be taken from the group consisting of regular or irregular horizontal cross section shape including circles, ovals, squares, triangles, polygons, or ridges.
The invention can include a surface having micro-features where the micro-features are between 70 μm and 1000 μm tall where the micro-structure density is between about 0.5% and 25% and includes the physical property of reducing heat transfer from a hot surface to a second surface that rests against the outer ends of the micro-features facing away from the hot surface. The micro-features are uniformly distributed in a random patterned array. The surface can be disposed on a beverage container. The beverage container can be held by a person from 11 seconds for a smooth cup to over 29 seconds for one with micro-structures when the beverage container includes liquid with a temperature of 190° F. or higher. Condensation or humidity on a cup containing a cold liquid and on a surface below the container can be decreased in relation to a beverage cup without the surface. The surface can include a decrease in condensation or humidity on a surface and that does not leave condensation on a surface below the container after 25 minutes in a humid environment. The surface can be made of rubber, paper, metal, plastic, glass, ceramic, or any combination. The surface can be made by injection molding, compression molding, lamination, embossing, stamping, sintering, additive manufacturing, milling, electrical discharge machining, casting, laser engraving, or by printing processes including ink jet processes, roll to roll contact print processes, intaglio printing, cast and cure transfer printing and similar printing processes. The surface can be made by ink jet printing, thermal printing, additive manufacturing, and the like, and any combination. The micro-features can include any regular or irregular horizontal cross section shape including circles, ovals, squares, triangles, polygons, linear ridges, or any combination thereof. The micro-features can be used in conjunction with other micro-features, dispersed within the same area, separated in distinct areas, or on the opposing side of the material carrying the micro-feature.
The invention can include a micro-featured surface with improved insulation and condensation resistance comprising: a micro-structure on a substrate having an arrangement of a first set of micro-features and a second set of micro-features; a first micro-feature horizontal cross section taken from the group consisting of a circle, oval, polygon, and concave portion; a first micro-feature horizontal cross section dimension included in the first set of micro-features in a range of 300 μm to 750 μm; a pitch included in the micro-structure in a range of 450 μm to 1650 μm; a spacing between the first set of micro-features in the micro-structure in the range of 300 μm to 1650 μm; a depth of the first set of micro-features in a range of 420 μm to 2000 μm; a condensation rate less than 0.15 grams when measured by an ambient test method; a second set of micro-features included in the first set of micro-features having a second micro-feature horizontal cross section taken from the group consisting of pillars and opening; a second micro-feature horizontal cross section dimension included in the set of micro-features equal to or less than 100 μm; and, an improved hold time of 23.00% or greater as shown by hold testing wherein a micro-feature density is in a range of 0.5% to 25.00%.
The second set of micro-features can include an opening defined in a top of a first micro-feature having a diameter of about 100 μm and extending into a micro-feature at least 50 μm. The surface can have pillars extending upward from a top of a first micro-feature having a width of about 50 μm and a height of about 50 μm. The pillars can include a width of a micro-feature in the first set of micro-features has a length greater than a width and are arranged offset relative to an adjacent first micro-feature in the micro-structure. The micro-features can be arranged in an alternating orthogonal pattern in the micro-structure.
The micro-features can include a micro-feature horizontal cross section dimension included in each micro-feature in the range of 300 μm to 750 μm; a pitch included in the micro-structure in the range of 450 μm to 1950 μm; a spacing between the micro-features in a range of 50 μm to 1650 μm; a depth of the micro-features in a range of 230 μm to 2000 μm; and, a condensation rate improvement greater than 25%. The micro-featured surface can include a micro-structure disposed on a substrate having a first set of micro-features included on the substrate and a second set of micro-features included in the first set of micro-features; a first micro-feature horizontal cross section taken from the group consisting of a circle, oval, polygon, and concave portion; a first micro-feature horizontal cross section having a width of about 200 μm; second micro-feature horizontal cross section taken from the group consisting of pillars and opening; a second micro-feature horizontal cross section dimension included in the set of micro-features equal to or less than 100 μm; and, an improved hold time of 23.00% or greater as shown by hold testing wherein a micro-feature density is in the range of 0.5% to 25.00%.
The construction designed to carry out the invention will hereinafter be described, together with other features thereof. The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein:
It will be understood by those skilled in the art that one or more aspects of this invention can meet certain objectives, while one or more other aspects can meet certain other objectives. Each objective may not apply equally, in all its respects, to every aspect of this invention. As such, the preceding objects can be viewed in the alternative with respect to any one aspect of this invention. These and other objects and features of the invention will become more fully apparent when the following detailed description is read in conjunction with the accompanying figures and examples. However, it is to be understood that both the foregoing summary of the invention and the following detailed description are of a preferred embodiment and not restrictive of the invention or other alternate embodiments of the invention. In particular, while the invention is described herein with reference to a number of specific embodiments, it will be appreciated that the description is illustrative of the invention and is not constructed as limiting of the invention. Various modifications and applications may occur to those who are skilled in the art, without departing from the spirit and the scope of the invention, as described by the appended claims. Likewise, other objects, features, benefits and advantages of the present invention will be apparent from this summary and certain embodiments described below, and will be readily apparent to those skilled in the art. Such objects, features, benefits and advantages will be apparent from the above in conjunction with the accompanying examples, data, figures and all reasonable inferences to be drawn therefrom, alone or with consideration of the references incorporated herein.
With reference to the drawings, the invention will now be described in more detail. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which the presently disclosed subject matter belongs. Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, representative methods, devices, and materials are herein described.
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The substrata can include a micro-structured side where the micro-feature included in the micro-structure is disposed away from an article where the micro-structure is attached. The micro-structure can be manufactured into an article, such as a cup, so that the substrate coincides with a surface of the article itself. In one embodiment, the substrate can be adhered to an article and therefore can include an attachment side to adhere the substrate to an article allowing the micro-structured side to face outward from the article.
Using the microstructure can increase the hold time a container containing a hot liquid can be held by a person, test subject, from 11 seconds for a smooth cup to over 29 seconds for a micro-structured cup in one embodiment. This is shown by hold testing, in one scenario, by having test subjects hold cups filled with water heated to at least 190° F. The cups were covered with polypropylene sheets that had various micro-surface patterns embossed on their outer surface. The time was measured until the cup was uncomfortable to hold and the person needed to set it down. Multiple repeats of the test were done to ensure that the results were valid. From these test, the following results were obtained as shown in Table 1 and
The micro-feature density on the outer wall is related to the improved insulation properties an anti-condensation property of the present invention. Micro-feature density is the ratio of micro-structured feature in a given area to the total area. For example, if a portion of the outer surface of the beverage container is 100 cm2 and the micro-feature structures occupy 10 cm2, then the micro-feature density would be 10%. The micro-feature density can be varied from 0% to 100%. Hold time (in seconds), in one scenario, relates to the micro-feature density (in percentages) as shown in Table 2.
From the data gathered in the hot cup portion of this study it appears that embodiment #128AP performed the best in average hold time when being observed in a general demographic or participants.
The present invention can also include several embodiments where the micro-feature height is varied and that hold time is affected by the micro-feature height. The relationship between the micro-feature height and the hold time is shown in Table 3.
A micro-feature that that is 420 microns tall and that has 1% contact to the skin, tested the same of the paper sleeve (in the range 52 to 65 seconds). The upper 50 microns of the pillar had reduced area of contact. The two level design prevented penetration into the skin to the depth of the nerves. Thus it was comfortable when squeezed (in either cups filled with hot or cold beverage). In one embodiment includes micro-features that are 1000 micron tall and have 11% contact to the skin. This embodiment tested superior to the paper sleeve (range 30 to 199 seconds). As shown, increasing the micro-feature height improves the hold time for a beverage container with hot liquid. Table 4 illustrates additional properties of the present invention.
Further testing was conducted with additional micro patterns developed as shown in Table 5.
Table 6 shows results of testing the additional surfaces.
In pair-wise comparison ranking measuring the time for several people holding the cups and comparing in pairs, micro surfaces H226AP and H227AP were superior to with use paper sleeve or the paper or polypropylene coated cups. H238AP, H239AP, and H240AP gave statistically the same hold time as when a paper sleeve was used and were superior to the paper or polypropylene coated cups. Further reduction of contact area and increases in height improved hold time.
We also see that a reduction of condensation, measured by weight, for a beverage container with a cold liquid based upon the particular microstructure pattern that is used. Referring to
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The present invention can also reduce the amount of condensation on the outer wall of the beverage container when the beverage container contains a cold liquid. Different micro-feature patterns are placed on the outer wall; beverage containers were covered with thin sheets of polypropylene and embossed with the various micro-patterns. The beverage containers were then filled with a precise amount of ice and water. The exterior surface was dried and then the cups were placed in a 100% humid chamber on a dry dish. The humidity chamber was continuously replenished with humidity from a container of boiling water. The cups and the dish under the cup were weighed every 5 minutes for 25 minutes. The results of the weight of the condensation on the beverage container for each of the microstructure patterns is generally shown in Table 7.
The weight in grams of the condensation in the dish placed under the beverage container is shown in Table 8 at various measurement times.
We also see that the height of the micro-features on the outer wall of the beverage container affects the amount of condensation produced. Generally, the higher the micro-feature height, the less condensation is produced. The relationship between the height of the micro-features and the condensation measured by weight is shown in Table 9.
Initial finding show that pattern #128AP is the best performer in gathering the least amount of condensation on the cup. Additionally pattern #128AP was also the best performer in the amount of condensation that fell off the cup into a dish beneath it. The control pattern overall did the worst except for in one instance where #003AP did slightly worse in the amount of condensation gathered into a dish.
The weight of condensation on the dish below the cup for various micro-feature densities is shown in Table 10.
The micro-patterns can be formed on paper, metal, ceramic, or plastic surfaces such as cups by embossing, stamping, injection molding, compression molding, laminating, ink jet printing, additive manufacturing processes, and by other ink printing processes. The ink printing processes can include techniques of using viscous inks that give raised features such as thermal transfer printing. Micro-features placed on the outer wall of a beverage container with heights between 70 μm and 1000 μm, and with micro-features densities of between about 0.5% and 25% reduce vapor condensation from a humid atmosphere.
In one scenario using an ambient test method, the test sample is a cup that is filled with ice water. The cup is placed on a pre-weighted dish. The cup and dish is placed in an ambient environment, such as an office setting or outdoors with humidity in excess 50%. After a pre-determined time, 1 hour in one scenario, the dish and cup is weighted and the difference from the prior weighting is recorded representing condensation.
In one embodiment a fog test method is used wherein a semi-sealed chamber with piezo humidifier generating fog equal to or greater than 90% humidity can be used. Boiling water placed in the chamber provides the humidity. In one embodiment, a fog generator is used including a chamber with a fan to circulate air to reduce or eliminate the humidity gradient. In one scenario, the lowering the fog generator output and potentially passing the fog through a mixing chamber to dissipate fog droplets into vapor results in around 75% relative humidity in the chamber. The results from these tests are shown in Table 11.
Additional information is shown in Tables 12A and 12B.
In one embodiment, the oval is an ellipse. The adjusted size can define the size of the top of the micro-feature and can be in the range of 380 μm to 460 μm. In one embodiment, the adjusted size at the top can be in the range of 450 μm to 460 μm. Additional Information is shown in Table 13. Note that in table 13, distance measurements are provided in millimeter. For width measurements, oblong features are shown with two dimensions, width and length, while the remaining is shown with one measurement representing the width and length of the micro-feature.
The anti-condensation properties of the present invention can be provided with specific micro-features and patterns. Any horizontal cross sectional geometric shape (circles, squares, triangles, holes or honeycomb, woven or punched mesh, ridges or any combination) can be used with spacing of 300 to 1200 microns; width 380 to 450 microns; depth 340 to 2000 microns; and optionally having sharp edges and with vertical sides of the micro features having draft angle less than 10 degrees. The micro-features can be added to a surface, substrate, product or tooling by molding, embossing, machining, extrusion, electrical discharge machining, laser engraving, contact printing, ink jet printing, 3D printing, rapid prototyping or other printing processes. The micro-features can be added to a surface adding a label, wrap, tape or sleeve made by molding, embossing, machining, extrusion, electrical discharge machining, or laser engraving. Surfaces having honeycomb and woven meshes can be used as auxiliary products such as sleeves, labels, tapes or wraps added to existing cold surfaces such as beverage containers, pipes, windows, and other embodiment wherein the physical properties of the present invention are advantageous. The through holes can improve visibility of liquid contents. Mesh and honey-comb products can be made by punching or piercing and stretching a sheet or made be made by weaving filaments to form a woven screen. The anti-condensation surface may be made of plastic, rubber, fiber, wood, metal, glass or ceramic. The anti-condensation micro-surface may be made of a different material than the cold surface.
It should be noted that multiple micro-features can be layers on a surface to provide for advantageous properties. For example, pillars on pillars or pillars on pillars on pillars.
In performing the tests to achieve the results described here and to describe the physical properties of the present invention, the objective is to determine a micro-feature pattern on a fiber hot cup that most effectively reduces surface contact points with a consumer's hand. By modifying the surface properties of the beverage container with micro-features, the consumer's comfort threshold is enhanced for holding beverage containers having a hot liquid and to provide a better grip. The beverage container can be single walled or double walled. This testing can include two phases, a motion oriented test and a thermal panel test. The motion oriented test aims measures the number of times the consumer must switch hands while walking across a predetermined distance and to also the timing at which it takes place. Additional consumer insight was gathered based off of questionnaires presented during each test. For the thermal panel test, consumers are given a cup set to compare and will be asked to fill out a questionnaire giving their temperature perception and ranking the hottest to coldest feeling cup.
The material used for the testing can include: hot plate (to insure the water stays the same temperature), coffee pot (to hold water inside between trials), water (kept at 190° F., tray (to transport cups to consumer), thermometer (measure the temperature of the water), stopwatch (timing how long people hold cup), cup samples, control cups, lids, sleeves, cup of room temperature (neutral temperature surface for use before each cup sample is tested), questionnaires, and walking space. The preparation for testing includes the steps of: preparing samples in packaging lab, labeling cups corresponding to different variables, marking fill level on all cups, validating how long it takes to fill, cap, and hand cup to consumer, providing pretest questionnaire to consumer via email after sign up, preforming a motion oriented test, recording which cup the consumer is testing before the motion test, preforming a thermal panel test, marking tray with corresponding letters to the sample ID's of each cup trial to match cups with questionnaires.
In performing a motion oriented test, pre-preparation steps are performed as stated herein. The temp of the water is measured to insure it is at the proper temperature, such as 190° F. in one test scenario. The sample to be tested is filled with the heated water to a predetermined level, between 60% and 95% full in one embodiment. The sample is placed on a tray. Test subjects are interviewed to inquire how they would hold the test sample, a cup on one test scenario and with which hand. The test subjects grip style on cup is observed and photographed. The test subject holds a neutral temperature cup, room temperature in one scenario, before handling test sample. The test sample is handled by the test subject. The test subject is requested to walk from a starting point, along a path, wherein the path represents normal walking pattern in one embodiment, while holding the test sample. The test subject is observed how many times the test subject changes hands, grip styles, or releases the test sample altogether. These events are recorded with associated timestamps. In one embodiment, the time stamps are determined from a video recording these events. Once the path is completed, the test subject is provided with a control sample with a sleeve and requested to repeat the path. In one embodiment, the path is reversed with the control sample. The test subject is provided with a questionnaire concerning the test sample and the control samples. The samples are collected form the set subjects at the conclusion of test.
When conducting the thermal panel test, the pre-test preparations are performed as stated herein. The temperature of the water is measured to insure that it is about 190° F. in one scenario. In one scenario, three test samples are selected to be provided to test subjects. The test samples are placed on a tray in predetermined positions (e.g. A, B, and C position). The test subjects were interview as to how they would hold the test sample and with which hand. The test sample is then filled with heated water and capped. Prior to allowing the test subject to handle the test sample, the test subject is provided with a neutral temperature sample prior to handling the test sample with heated water. The test subject is then instructed to handle the test sample until it is no longer comfortable to do so. The time is observed and recorded and once the test subject releases the first test samples, the process is released for additional test samples (e.g. A, B, and C). The test subject then ranks the test samples from hottest to coldest. In one scenario, the test subjects rank 1 to 3 with 1 being no difference and 3 being a large difference in temperature between the test samples. The hold time for each test subject for each test samples can also be recorded, correlated with the ranking and used to provide some validation of the ranking. The test subjects can then be interviewed concerning any additional comments directed to the grip or other measureable attributes from a questionnaire.
The testing for determining the physical properties of the concerning condensation were performed using the following materials: hot plate (heat water to create humidity chamber), coffee pot (hold water during heating), water (water will be kept at 190° F. or above), tray (transport cups), thermometer, stopwatch, lids for cups, beaker, and scale.
The following procedures can be followed to perform the thermal panel test that can include the following steps. First, a heating source such as a hot plate can be activated and heat a liquid such as water in a first container. The temperature of the heated liquid is measured periodically and recorded. A second container is used with dishes that can be placed around the container. Each dish can be assigned to the test sample and the initial weight of each dish with the test sample and optionally a lid is taken and recorded. The test samples can be filled with ice and a liquid such as water. In one embodiment, the test samples are filled with between 150 and 225 grams of ice and 100 to 300 grams of water. Lids can be placed on the test samples. When the water in the first container reaches or exceed about 180° F., in one scenario, the test samples are placed on the respective dishes. The heated liquid is place on the second container and a covering is placed over the second container and the test samples to create a humidity chamber. The time is recorded and once a pre-determined period of time has elapsed, the cover is removed. The weights of each test samples, each dish, and the final temperature of each cup. The difference in the weight of the cup initially and after the above process represents the amount of condensation.
Unless specifically stated, terms and phrases used in this document, and variations thereof, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. Likewise, a group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should also be read as “and/or” unless expressly stated otherwise.
Furthermore, although items, elements or components of the disclosure may be described or claimed in the singular, the plural is contemplated to be within the scope thereof unless limitation to the singular is explicitly stated. The presence of broadening words and phrases such as “one or more,” “at least,” “but not limited to” or other like phrases in some instances shall not be read to mean that the narrower case is intended or required in instances where such broadening phrases may be absent.
While the present subject matter has been described in detail with respect to specific exemplary embodiments and methods thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily produce alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art using the teachings disclosed herein.
This application claims priority from U.S. Provisional Application 62/291,833 filed Feb. 5, 2016.
Number | Date | Country | |
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62291833 | Feb 2016 | US |