WO2015130992A1 - Biocidal sachet for food safety - Google Patents

Abstract

Disclosed are food packaging and commercial materials and processes which incorporate the release of chlorine dioxide gas that are useful for commercial products to extend the freshness and preserve the integrity and shelf-life of packaged foods and also retard the onset of mold on organic fiber bales. Food packaging and commercial materials, in the form of a sachet, utilize a low bioburden, biodegradable and/or compostable nonwoven structure (105) and some form or forms of an antimicrobial and/or antifungal agent consisting of silver or silver-based species that destroy microbes on the sachet material itself which would otherwise spoil the food, together with the release of gas-phase chlorine dioxide gas initiated by contact of sachet with ambient air. The shelf-life extension and mold mitigation process primarily involves the chlorine dioxide gas reducing and mitigating, a) the spread of food spoilage pathogens on all the surfaces of the food itself and all areas of the food packaging environment and b) the spread of mold pathogens on all surfaces of the organic fibers itself and all areas of the organic fiber packaging environment.

Description

BIOCIDAL SACHET FOR FOOD SAFETY

Related Applications

[0001] The present invention claims priority from United States Provisional Patent Application No. 61/945,853 filed 28 FEB 2014, the contents of which are herein incorporated by reference in their entirety.

Field of Invention

[0002] This invention relates to a chlorine dioxide gas generating biocide sachet to reduce and mitigate the presence of pathogens on fruit and other foods and on organic fibers for purposes of food safety, shelf-life extension and mold mitigation. The inherently low bioburden absorbent nonwoven medium comprises biodegradable and/or compostable materials which do not support bacterial growth. This in conjunction with at least one antimicrobial agent such as silver-based and/or silver ion-based active ingredients in the absorbent media or other packaging material together with dry chemistry, which upon reacting with moisture in ambient air releases chlorine dioxide gas that permeates from the inside of the sachet to the food, commercial and industrial packaging environment wherein it is placed. The sachet of the present invention functions to destroy microbes within the packaging environment. As the gas phase biocide comes in contact with the contents of the package, such as fresh produce or organic fiber, food or fiber integrity is preserved and the shelf-life is extended due to the mitigation and retardation of the bacterial and fungal pathogens that are responsible for food and organic fiber spoilage. Active ingredients that are part of the packaging sachet of the present invention can function in the condensed phase and the biodegradable nonwoven pad incorporated in a package can function as a carrier and/or a release vehicle for one or more antimicrobial and/or antifungal chemicals and/or other actives.

Background of the Invention

[0003] In the United States an average of 35% of strawberry fruit is lost due to infection by Botrytis cinerea, a spore bearing fungus. The control of B. cinerea in harvested strawberries is critical, for minor amounts of fruit decay will cause a shipment to be unmarketable [Blacharski, R.W. et al "Control of Postharvest Botrytis Fruit Rot with Preharvest Fungicide Applications in Annual Strawberry". Plant Disease 85(6) 597-602 (2001 )]. Currently, the USDA grade 1 standard states that decay from pathogenic microorganisms cannot exceed 2% of the fruit, in a given lot, with visible defects [United States Department of Agriculture. "United States Standards for Grades of Strawberries" a lot is to fail grade 1 standards, significant losses due to reduction in price or rejection of shipment will be incurred by the grower].

[0004] Botrytis cinerea and Rhizopus stolonifer are the most severe post-harvest diseases of strawberries which cause severe loss of yield during storage and longdistance transport from cold store to market [Vardar, C. et al. "The Application of Various Disinfectants by Fogging for Decreasing Postharvest Diseases of Strawberry". Post- Harvest Biology and Technology 66: 30-34 (2012)]. Produce contaminated by mold are, also, susceptible to infection by Salmonella, Escherichia coli 0157:H7, and Clostridium botulinum. The pH level of strawberry tissue increases as a side effect of the mold infestation, which in turn enhances microbial growth conditions [Sy, K.V. et al. "Efficacy of Gaseous Chlorine Dioxide as a Sanitizer for Killing Salmonella, Yeasts, and Molds on Blueberries, Strawberries, and Raspberries". Journal of Food Protection 68(6): 1 165- 1 175 (2005)]. Strawberries are vulnerable to bacterial and fungal contamination due to harvesting and packaging. After harvesting, strawberries are not washed before packaging, since a minute amount of moisture will cause the fruit to rapidly decay.

Unwashed strawberries lead to a greater risk of microbial and fungal colonization leading to the increased importance of developing alternative sanitation methods to prevent unnecessary foodborne illness and devastating losses due to bacterial and fungal contamination.

[0005] Chlorine dioxide has been previously utilized in efforts to inactivate foodborne pathogens, molds, and yeasts on a variety of produce including, strawberries [Han, Y., et. al. "Decontamination of Strawberries Using Batch and Continuous Chlorine Dioxide Gas Treatments", Journal of Food Protection, Vol. 67, No. 1 1 , 2004, Pages 2450-2455] but not limited to, blueberries, tomatoes, potatoes, and lettuce [Wu, V. et al. "Effects of a Simple Chlorine Dioxide Method for Controlling Five Foodborne Pathogens, Yeasts, and Molds on Blueberries". Food Microbiology 24(7 ^'-8): 794-800 (2007) and Sun- Young, Lee et al. "Efficacy of Chlorine Dioxide Gas as a Sanitizer of Lettuce Leaves", Journal of Food Protection, Vol. 67, No. 7, 2004, Pages 1371-1376 and Wu, V. et al. "A Simple Instrument-free Gaseous Chlorine Dioxide Method for Microbial Decontamination of Potatoes During Storage". Food Microbiology 27(1 ): 179-184 (2010)]. Shin et al.

reported that 5 ppm chlorine dioxide was effective at reducing Listeria monocytogenes and Escherichia coli 0157:H7 inoculated on apples, lettuce, and cantaloupe by at least 5 log CFU/g [Shin, Y.J. et al. "Effect of a Combined Treatment of Rice Bran protein Film Packaging with Aqueous Chlorine Dioxide Washing and Ultraviolet-C irradiation on the Postharvest Quality of 'Goha' Strawberries". Journal of Food Engineering 1 13(3): 374- 379 (2012)]. In recent studies, chlorine dioxide has been proven efficacious for the mitigation of B. cinerea on figs [Karabulut, O.A. et al. "Evaluation of the use of chlorine dioxide by fogging for decreasing postharvest decay of fig" Post-Harvest Biology and Technology 52(3); 313-315 (2009)]; however, the strawberry industry has signaled it will not use chlorine dioxide as a pre-wash. Therefore, since there remains a need to provide a product suitable for use, for example as a versatile in-transit sanitizer and shelf life extender, this invention of a controlled and sustained release of vapor phase chlorine dioxide is directed toward this need as described herein.

[0006] Cotton displays 3rd order biotic activity wherein goods in which respiration processes (external respiration) are suspended, but in which biochemical, microbial and other decomposition processes still proceed. Mold growth caused by heat and moisture may start even in the cotton field. This leads to a reduction in value by staining and discoloration due to rot. In damp weather (rain, snow), the cargo must be protected from moisture, since cotton is strongly hygroscopic and readily absorbs moisture. This may lead to discoloration, decay, mold, mildew stains and rot. In addition, the cotton may swell by absorbing water vapor, resulting in an increase in volume of 40 - 45%. A high water content is difficult to detect from outside, since the cotton does not feel damp even with a water content of 20%.

[0007] Cotton exhibits low resistance to bacterial degradation and mold growth. Mycelial fungi cause circular mildew stains which are gray/yellow/green, orange/red and brown/black in color, together with a musty odor. Particularly active on cotton is the mold Stachybotrys sporium, which penetrates into the lumen of the cotton fiber. Within 10 days, the cotton loses 30% of its strength by cellulose degradation. Mold and bacteria change the color of the cotton to yellow, yellow/green, orange, red to chestnut-brown and gray. This is accompanied by a loss of luster. At 25 - 35 °C and a relative humidity of 80 - 90%, these variations may be observed after 3 - 4 weeks. It is estimated that approximately 50% of world cotton production is destroyed by parasites and diseases.

[0008] One prior art method of controlling the package atmosphere is the use of what is termed in the food packaging industry as Modified Atmosphere Packaging (MAP) where, generally, the relative concentrations of oxygen, carbon dioxide and nitrogen are adjusted relative to each other to preserve the integrity and freshness of the particular packaged item. A good review of Modified Atmosphere Packaging is provided in the art by Church and Parsons (Church, I.J. & Parsons, A.L.: (1995) Modified Atmosphere Packaging Technology: A Review, Journal Science Food Agriculture, 67, 143-152), as well as Beaudry (Beaudry, R., MAP as a Basis for Active Packaging, in Intelligent and Active Packaging for Fruits and Vegetables, C.L. Wilson, Ed. CRC Press, 2007. pp. 31 - 55).

[0009] It is recommended that if mold is discovered, the organic fiber product should be isolated by sealing it in a plastic bag as this will prevent the transfer of spores to other areas. Additionally, it is said to quickly as possible engage in air-drying to prevent further mold growth or to place the organic fiber product in a freezer to prevent further mold growth. None of these methods are commercially viable for large scale needs of the industry to ensure satisfactory levels of mold mitigation. Cotton bales already are placed in plastic bags and mold incidence is not mitigated because the mold spores are still present in the bag itself. In freezing methodologies, which are not possible on a commercial scale due to infrastructure cost, the mold's vegetative growth will freeze and break down but the spores are able to withstand the cold temperatures and remain viable.

[ooio] Irradiation of cotton bales has also been recommended in the past. The absorbed irradiation energy activates the absorbing molecules and gives rise to primary reactive species including ions, free radicals and excited molecules. These activated molecules have the ability to initiate chemical reactions with other molecules present in the system. The reactive species diffuse out of the sites of their formation and chemically attack various other biomolecules, including nucleic acids (DNA, RNA), membrane lipids, proteins, carbohydrates and others, causing damage to them and in doing so can potentially retard mold mitigation. But there are several important reasons irradiation is not widely adopted. First, the costs are high. Second, irradiation is a sophisticated technology that is hard to adopt by the industry. And third, there is a risk that the irradiation has an adverse effect on cotton properties ( The effect of quarantine-level gamma irradiation on cotton fiber and its subsequent textile processing performance, MHJ van der Sluijs and Jeffrey Church, Textile Research Journal 0040517512458341 , September 18, 2012).

[ooii] One disadvantage of the prior art methods for generating chlorine dioxide gas generally is that unsatisfactory levels of by-products or reactants remain as a residue. For example, in the case of chlorine dioxide gas, the byproduct chlorite leaves residues on food handling equipment. Human contact with such residues should be avoided or substantially minimized according to FDA and EPA regulations. Another requirement in the food handling and related industries is the need for raw materials or ingredients that are safe to handle in the preparation of the disinfectant. The requirement is for the inclusion of reagents that are safe to use and, after generating chlorine dioxide, only produce side products that are non-toxic and/or biodegradable. [0012] Also, although it has great beneficial characteristics, chlorine dioxide cannot be transported commercially as a concentrated gas for its use and instead has been generated at the site where it is used. Thus, an on-site gas generation plant typically is required to generate the gas that is then delivered to the fluid in which it will be used. Such apparatus takes up space and represents a significant added expense. Moreover, even when prior art apparatus do not require a separate gas generation component e.g., those shown in European Patent Publication No. 0 571 228 for sulfur dioxide generation, such apparatus are still undesirable because controlling the amount of gas generated, the efficiency of the generation, and the duration of the gas generation has proven difficult, if not unsuccessful. Other related prior patents include the following.

[0013] U.S. Patent No 50751 17 assigned to Kabushiki Kaisha Nasha describes an invention for an aqueous stabilized chlorine dioxide solution which uses a water solution as the method of trigger for the release of gas and absorbing ethylene gas in the food package with the use of pulverized absorber. This invention fails to provide dry chemistry for the release of chlorine dioxide gas from a sachet constructed from biopolymer non-woven materials.

[0014] U.S. Patent 6046243 assigned to Bernard Technologies Inc. describes an invention for the release of chlorine dioxide gas from a manufactured polymer film that may or may not be layered as a hydrophilic or hydrophobic laminate structure. This invention is similar and related to inventions mentioned in U.S. Patents 5914120, 5707739, 5705092, 5695814 and 5668185 assigned to Southwest Research Institute. Such an invention has the considerable risk of complicated manufacturing methodology and difficulty in tuning the amount of chlorine dioxide that is to be released. There is no teaching about a sachet pouch manufactured from biopolymer non-woven or about using dry chemistry powder for the release of the chlorine dioxide gas.

[0015] U.S. Patent 5980826 and U.S. Patent 5922776 assigned to Bernard Technologies Inc. describe inventions that can be applied as a composite onto a surface utilizing multilayered hydrophilic and hydrophobic materials. The authors describe in detail how a composite film structure can release chlorine dioxide gas with all the chemical constituents captured in the actual polymer layer material micro-dispersed in a continuous and dispersed phase with an intermediate boundary layer as necessary.

[0016] U.S. Patent 7150854 assigned to Englehard Corporation describes an invention which releases chlorine dioxide on coming into contact with water due to the presence of a chlorite and chemical reagent in two separate boundary and material layers physically separated from each other. There is no discussion of dry chemistry mixed together and present in a sachet wherein there is no need for any separation. [0017] U.S. Patent 7566495 assigned to Avery Dennison Corporation relates an invention which is an antimicrobial composite material composed of two polymer mixtures to comprise a film, label, label-stock or similar construction. Such films are difficult and expensive to manufacture and the release of the chlorine dioxide gas may be non-uniform and uncontrolled due to the multitude of manufacturing processes that need to be tightly controlled but are not possible for high-throughput manufacturing. There is no teaching of dry chemistry residing together in powder form in a biopolymer non-woven sachet. This invention is similar to U.S. Patent 7910204 and U.S. Patent 7914888 assigned to Avery Dennison Corporation lacking the teaching mentioned.

[0018] U.S. Patent 8163384 assigned to Avery Dennison Corporation is similar to U.S. Patent 7566495 with the exception of the inclusion of an adhesive layer on the label-stock and which provides the inclusion of the dry chemistry powder into the polymer structure of the non-woven material.

[0019] U.S. Patent Application 20030053931 assigned to Selective Micro Technologies, LLC describes an invention which is a series of reactants contained in envelopes that generate chlorine dioxide gas in the presence of an initiating agent. Nothing in this reference provides an envelope from biopolymer non-woven, nor one sole envelope manufactured as a sachet which contains all the reactants together and which generates gas in the presence of an initiating agent such as ambient air.

Summary of the Invention

[0020] The present invention seeks to obviate or mitigate the foregoing disadvantages of the previous improvements.

[0021] One aspect of the present invention includes a biocidal sachet for food safety, the sachet including: at least one layer of non-woven fibers including one or more biodegradable, bioresorbable thermoplastic polymers and one or more antimicrobial agents, the at least one layer forming an envelope, the fibers being oriented to maintain paths for liquid and gas flow within the at least one layer, the paths being substantially transverse to an exterior surface of the envelope; chlorine dioxide release chemistry retained within the envelope, the chemistry including a dry composition provided to release chlorine dioxide gas when in contact with ambient air; and a bioresorbable, biodegradable hydrophilic surface coating on a substantial number of the fibers, the coating providing an adjusted release of said chlorine dioxide gas.

[0022] The present invention is significantly different from prior art in the use of dry chemistry for the release of chlorine dioxide gas from a sachet constructed from biopolymer non-woven materials. Moreover, there is no prior art teaching about a sachet pouch manufactured from biopolymer non-woven or about using dry chemistry powder as utilized in the present invention for the release of the chlorine dioxide gas.

[0023] The present invention provides that the dry chemistry is mixed together and present in a sachet wherein there is no need for any separation.

[0024] In contrast to prior improvements, the present invention does not contemplate the inclusion of the dry chemistry powder into the polymer structure of the non-woven material.

[0025] The present invention teaches and exemplifies an envelope from biopolymer non-woven. As well, the present invention teaches and exemplifies an envelope manufactured as a sachet which contains all the reactants together and which generates gas in the presence of an initiating agent such as ambient air.

[0026] The present invention is unique in being able to release chlorine dioxide vapor in a controlled fashion over the course of several days with the initial trigger of the reaction being just ambient conditions.

[0027] The present invention does not require the costly and complicated on-site manufacturing and delivery of chlorine dioxide gas into the food packages, nor the necessity for a separate generation plant or unwanted by-products, but rather specifically delivers the gas in-situ in the food package itself.

[0028] The present invention releases the chlorine dioxide gas when the dry powder comes in contact with the humidity associated with ambient air not requiring any other activation (light, pressure, temperature, et. a!) source.

[0029] Another unique aspect of the present invention is that delivery of the chlorine dioxide gas is accomplished via the dry chemical components that release the chlorine dioxide gas upon contact with ambient air to be contained in a sachet manufactured from biodegradable and biocompostable biopolymer in a high-throughput manufacturing environment with specific characteristics which aid in the controlled release of the chlorine dioxide gas. This provides the customer with the cost-effective capability of implementing the action of the chlorine dioxide within the food package itself as it is packaged and transported in order to mitigate and retard the propagation of the mold and hence positively increase the shelf-life.

[0030] At the current time there is no commercial solution in the market which has resulted in a significant market demand for a viable approach to address the reduction of spoilage rates in strawberries and similar fresh produce, or to reduce the propagation of mold in organic fiber. [0031] Other aspects and features of the present invention will become apparent to those ordinarily skilled in the art upon review of the following description of specific embodiments of the invention in conjunction with the accompanying figures.

Brief Description of Drawings

[0032] The foregoing features of the invention will be more readily understood by reference to the following detailed description, taken with reference to the following accompanying drawings, in which:

[0033] FIGURE 1 is a schematic of a meltblown fiber manufacturing line for use in manufacturing a biocidal sachet in accordance with the present invention.

[0034] FIGURE 2 is a schematic of a non-woven calendering manufacturing station for use in manufacturing a biocidal sachet in accordance with the present invention.

[0035] FIGURE 3 is a graph of experimental trial matrix and performance data for different fiber diameters.

[0036] FIGURE 4 is a magnified photograph of fibers from 0.015 inch nozzle.

[0037] FIGURE 5 is a photograph showing PLA non-woven in a cross-section of the layer with fiber direction being transverse to an exterior surface.

[0038] FIGURE 6 is an additionally magnified photograph showing PLA non- woven in a cross-section of the layer with fiber direction being transverse to an exterior surface.

[0039] FIGURE 7 is an additionally magnified photograph, PLA non-woven in a cross-section of the layer with fiber direction being transverse to an exterior surface.

[0040] FIGURE 8 shows a chlorine dioxide sachet in accordance with the present invention at the base of a strawberry clamshell.

[0041] FIGURE 9 shows sachet in accordance with the present invention made for pallet testing and includes two sets of four (4) 7.5 inches by 4.5 inch sachets adhered together on the left and right of the photograph.

[0042] FIGURE 10 shows sachet construction in accordance with the present invention and includes four (4) sachets 7.5 inches by 4.5 inches shown placed on the left hand of a flat of strawberries with another four (4) on the right hand side under corresponding filled strawberry clamshells.

[0043] FIGURE 11 shows a roll of PLA film material for construction of biocidal sachets in accordance with the present invention.

[0044] FIGURE 12 shows the cut strip of PLA film prior to construction of the biocidal sachet in accordance with the present invention. [0045] FIGURE 13 shows the three side sealed biocidal sachet manufactured from PLA in accordance with the present invention.

[0046] FIGURE 14 shows the open biocidal sachet prior to insertion of dry chemistry and sealing of the fourth edge in accordance with the present invention.

Detailed Description of the Invention

[0047] As used herein, the term "polymer" refers to thermoplastic, natural, naturally-derived, synthetic, biopolymers and oligomeric species thereof. As used herein, the term "oligomer" refers to a low molecular weight polymer of two or more repeating monomeric repeating units. Polymers specifically include, but are not limited to, PolyLactic Acid (PLA); PolyCaproLactone (PCL) and PolyHydroxyAlkanoate (PHA) alone or in blends/alloys or as copolymers.

[0048] The non-woven material layer prepared according to embodiments of the invention described herein utilizes natural or naturally-derived fibers, especially polylactic acid, as the basis of the material for the sachet structure. The non-woven material is completely biodegradable; its composition can be varied to provide the ability to vary the degradation. The non-woven layer can also be modified with hydrophilic and hydrophobic materials to vary its ability to release the chlorine dioxide gas.

[0049] More specifically, in some embodiments of the invention of the non-woven layer, the non-woven materials have a fibrous structure as described herein.

[0050] In one embodiment of the invention, the non-woven material includes a bioresorbable layer having a plurality of bioresorbable fibers and a bioresorbable hydrophilic surface coating on a substantial number of the fibers if so desired. The layer has a surface for cross-linking or "engaging" with other possible layers of the structure. The fibers are oriented to provide compression resistance and maintain paths, for liquid- flow and air-flow, preferentially in a direction transverse to an exterior surface. The orientation of the fibers within the layer can be arranged such that they provide resistance to this crushing effect and maintain transverse paths for the air-flow and fluid- flow.

[0051] Examples of useful fibers are those of plant or natural, animal, and synthetic origin, as well as fibers classified as naturally-derived origin. Examples of natural or plant-origin fibers are, but not limited to alginate, cotton, bamboo, jute, flax, ramie, sisal, hemp, polyethylene blend with hybrid plant-origin polymer, and

polypropylene blend with plant-origin polymers). Examples of animal-origin fibers are, but not limited to, proteins such as collagen, silk, and keratin. Examples of synthetic fibers are, but not limited to, polyesters, including materials that traditionally are not found in fibrous form such as polyurethane and silicone or silicone-based fibers. In some embodiments, the preferred polymer is polylactic acid (PLA) and/or copolymers of PLA which are biodegradable and with low inherent bioburden.

[0052] Such biodegradable and low bioburden fibers include those based on polylactic acid, also known as polylactide, and its various L, D and meso configurations, including mixed L, D, and meso compositions, their various crystallinities, molecular weights, and various co-polymers. In this work polylactic acid is understood to be synonymous with polylactide and both terms encompass all the optically active variations of the polymer.

[0053] PLA is also bioresorbable. The term bioresorbable refers to materials that can be broken down by the body should it not be manually removed therefrom. An example of such a material is a bioresorbable suture based on a polylactic aid copolymer.

[0054] In the present invention, although we can utilize synthetic fibers such as polypropylene and polyethylene, or paper such as recycled paper, we preferentially employ natural plant-based materials, such as natural polymers or naturally-derived meltblown nonwoven polymer fibers or filaments. One example is polylactic acid (PLA), as defined above. The PLA is degradable and renewable, and has a low bioburden as opposed to, for example, recycled wood pulp. From an end-use standpoint and a processing and manufacturing standpoint, the low bioburden profile achieved with the nonwoven process precludes any heat drying that is required to destroy microbes present in a wood or tissue-based product; allowing a "cleaner" and safer system when compared to traditional alternatives such as wood pulp.

[0055] Another differentiating feature of PLA is that it is completely compostable, resorbable and safe in terms of cytotoxity, versus recycled pulp or synthetic fibers. One of the degradation products of polylactic acid is lactic acid, which is produced in the human body.

[0056] In some embodiments, 100% PLA polymer may be used. In some other embodiments, co-polymers of PLA with masterbatch additives and/or plasticizers may be used with distinct advantages. As an example, when polycapralactone, a degradable polymer often used in medical implants, is incorporated at up to 50% of the blend with PLA, the fibers exhibit flexibility and softness to counteract the inherent brittle nature of the PLA. Other additives such as plasticizers and lubricants may also aid in the fiber- spinning process. [0057] Natu reWorks (Minnetonka, MN) produces several grades of PLA in pellet form that can be melt processed into film or fibers and are useful in this invention. Many grades are useful, however high melt-point versions with the optional use of low-melt binder fibers have proven to process well in the present invention. Perstorp (Toledo, OH) produces PCL and, although several grades are suitable for use in the present invention, grade Capa 6800 processes well. Mirel PHA from Metabolix (Cambridge, MA) is also compatible with the present invention.

[0058] When processing PLA to maintain maximum chain length, it is important to dry the polymer in a commercial desiccant dryer such as a Conair (Cranberry

Township, PA) "W" series machine to a moisture level below 200 ppm. This is critical as PLA polymer is extremely hydroscopic and will acquire moisture from the air rapidly. This moisture hydrolytically degrades the polymer chains, especially in the presence of processing heat, resulting in reduced viscosity and product strength. If moisture levels are too high, the additional problem of steam generation and uncontrolled pressures within the extrusion system are observed.

[0059] As exemplification, for production, a Davis-Standard (Pawcatuck, CT) single screw 30:1 2.5" extruder (or equivalent) with melt temperatures of 350 to 425 °F and pressures of 500 to 2000 psi are achieved at the outlet. The polymer passes thru filtration to remove particulate debris and enters a pressure control zone achieved via a positive displacement Zenith (Monroe, NC) gear pump. Molten pressurized polymer is delivered to a melt-spinning die produced by BIAX (Greenville, Wl). Several arrangements of nozzles, diameters, and total nozzle count can be varied to suit the polymer and final production needs. A typical spinning die contains 4000-8000 nozzles/meter of width with an internal diameter of 0.25 - 0.50 mm may be utilized efficiently. It must be noted that melt spinning dies produced by other suppliers such as Hills (W. Melbourne, FL) or Reifenhauser (Danvers, MA) may be used.

[0060] Heated and high velocity air is introduced into the die and both polymer and air steams are released in close proximity allowing the air to attenuate the polymer streams as they exit the die. Air temperatures of about 230-290 °C with pressures at the die at about 0.6 to about 4.0 atmospheres may be used. Following extrusion and attenuation, cool and/or moist air may be used to quench the fibers rapidly. At this point, liquids or mists can be applied to coat the surface. Surfactants, antimicrobials, or adhesives can be beneficially adhered to the fibers.

[0061] The fibers may be collected on a single belt or drum or a multiple belt or drum collector. Air is drawn from below the belt(s) or drum(s) and fibers collect in a web or matt on the surface. There are many adjustments in the entire system, temperatures, pressures, quench conditions, extrusion air velocity, suction air velocity, etc. With these adjustment points, a matt that is, for example, stiff and thin or flexible and fluffy is possible. For this invention, a low-density structure with fine-diameter fibers is beneficial although one of skill in the art will realize that other densities and diameters are suitable for use in the present invention. The low density improves fluid acquisition and the small diameter maximizes surface area, which is important for the release of "actives" from the fibers.

[0062] Fiber diameters can range from approximately 1 to 30 microns (μιη) however it is possible to produce nano or sub-micron fibers via increased hot air attenuation and/or low polymer throughputs. The cost of production increases as a result however, the overall surface area of the fibers increases. Likewise, larger fibers are easily produced when attenuation air is reduced or eliminated and/or melt pressures are increased. A compromise of cost and performance is seen in, approximately, the 5 - 25 micron range. Within the large number of consecutive fibers being spun, it can be important to allow a range of diameters as this has been observed to increase the loft or thickness of the structure and this provides for improved shock absorbing and cushioning properties. Different diameters can be achieved by adjusting the internal nozzle diameters and/or air velocity at certain nozzles or by directing external cooling air toward certain fiber streams.

[0063] The fibers can be formed in a continuous melt spinning operation and arranged into a web as described above. The fibers can also be cut into staple and processed via carding or air-laying and needle-punched or vertically lapped (Strudo). Additionally, staple fibers can be formed into a structure via chemical bonding or reinforcing of the fibers. They can also be thermally bonded in a hot-air oven or via ultrasonic techniques. The diameter of the fibers is selected largely to provide desired compression resistance.

[0064] Another feature differentiating the present invention from the prior art is that in the present invention the method of meltblowing the PLA fibers into continuous filaments is novel and non-obvious and imparts unique characteristics to the functional sachet of the present invention. The unique characteristics allow, for example, for the incorporation of multiple layers of fibers and filaments that serve specific functions including, but not limited to, three-dimensional structures or formed layers using pattern forming techniques. The multiple layering is also useful to provide specific absorbency without the need to perform separate lamination operations, as is typically done in the prior art. Separate lamination operations encompass a sequence of discrete process steps wherein sheets and webs are created on separate forming stations or machines and then utilizing a bonding system, the individual webs are thermally or adhesively or ultrasonically fused together.

[0065] In another embodiment of the present invention, the PLA fibers of the present invention can be used in combination with other fibers such as spunbond polypropylene or polyethylene, but the fibers used with the PLA fibers of the present invention are not limited to those two materials. Additionally, hydrophilic or hydrophobic layers in a single layer or multilayer construction are possible where either the PLA or the other polymer, or both, are treated with materials to render the nonwoven filaments hydrophilic or hydrophobic, depending on the end use and purpose. The hydrophilic and hydrophobic materials can be introduced in the fiber prior to extrusion via

masterbatching or via a subsequent process such as coating, spraying or dipping. The introduction of hydrophilic and hydrophobic materials to the fibers is not limited to the techniques mentioned here but can be accomplished by any technique available to those of ordinary skill in the art.

[0066] In some embodiments, fiber-reinforced layers may be prepared using composite fibers such that the fibers' core provides strength and rigidity while coatings on the fibers provide moisture holding or gelling ability. The absorbent outer structure can be applied, when the fibers are formed in a secondary process, which is generally preferred. Alternatively, it is also possible to include a thermoplastic moisture sensitive polymer into the mix such as polyoxethylene while extruding the fibers.

[0067] In some embodiments, the fibers can also be core-shell type fibers, where the inner core is a polymer fiber of one type such as one that provides strength to the fiber, and the outer shell or sheath represents another polymeric material such as one that is moisture absorbent and/or has gelling properties. Core-shell types of fibers may be made in a variety of combinations of natural, naturally-derived, and synthetic polymers.

[0068] In some embodiments, the fibers can be coextruded to provide a low-melt outer surface for thermal bonding. The outer surface can also be used to deliver "actives" such as antimicrobials that release from the fiber surface. Antimicrobials, active ingredients, or materials that assist degradation, can be "master batched" in the polymer melt and extruded with the fibers. Thus, in some embodiments, the entire fiber structure, not just the periphery of the fiber, can be used to deliver active ingredients.

[0069] In other embodiments, the fiber structure can also be hollow. The hollow structure can be modified by varying wall thickness, inside diameter of the fiber, and outside diameter of the fiber. The dimensions of the hollow fiber can be tuned, for example, to allow for increased surface area, porosity, absorbency, moisture vapor transmission rate, compression resistance, tensile strength, and active ingredient release rate.

[0070] In some embodiments, the nonwoven fibers may be further exposed to a coating process. Such processes are known in the art and include, but are not limited to, roll coating, gravure coating and/or printing, , roto-press printing, slot die coating, spraying, dipping, saturating, kiss coating, partial saturation coating, Dahlgren coating, and so on. Multiple coatings can be applied in-line or in subsequent processes. The coating need not have total fiber coverage, and may be surface-oriented and/or pattern coated. In some embodiments, one side only of a nonwoven fibrous web may be treated. In some other embodiments, both sides may be treated.

[0071] Coating may be used for a variety of reasons such as a) to vary the hydrophilic/hydrophobic nature of the structure, b) to provide fluid holding capacity if desired, c) to contain and deliver a fragrance, "active" agent or antimicrobial, or d) to contain some material that will assist the degradation or biodegradation of the fibers. The coating(s) could also be biocompatible and bio-resorbable. These coatings can be selected from, but not limited to: cellulose, collagen, alginate, chitosan, gums, starch, ethylene glycol species, propylene glycol species, poly oxethylene, polylactic acid, polyhydroxyalkaonates (PHA's), polyglycolic acid their co-polymers, and blends thereof. The coatings can include antimicrobial active ingredients such as, but not limited to, silver or silver-species and iodine and iodine-species. The coatings can also include chemical systems necessary for delivery of antimicrobial species.

[0072] In some embodiments, the fibrous scaffold may be coated with a full surface coating. Certain embodiments of this coating can also be mixed or injected with air or a gas, including water or steam, to reduce density and provide mechanical pores and wicking channels. The gas can be generated in-situ chemically or generated and frothed immediately prior to application. Effervescent gas-generating chemistry that reacts in the drying and/or curing phase may be advantageously used in the

manufacturing process. The coating is dried, cured and generally solidified before use. In some embodiments, the structure may be cross-linked for greater integrity and strength, especially if the coating has the ability to swell and form a gel.

[0073] The extruded fibers can be any denier or tex, both terms defined as the mass of the filament or fiber in grams of 9,000 meters or 1 ,000 meters respectively. The extruded fibers can also range from a minimum diameter of 1 micron to a maximum diameter of 100 microns. The fibers can be additionally processed to create more porosity, structure, and fluid-holding capability. [0074] In our invention for the non-woven material layer, PLA fibers may be thermally glazed (calendered). Heat applied with calender rolls and even exposure to blasts of hot air, can provide the nonwoven filaments which comprise the entire non- woven web material with a smooth film-like surface. Yet the non-woven layer may still have porosity to fluids and/or moisture vapor, and the porosity can also be controlled. The fiber glazing process may be used instead of application of a film, and provides a unique and advantageous method to control fluid flow in the nonwoven fibers, with a minimum of lamination and processing effort. Glazing can be applied as a treatment on an overall surface of fibers or various areas of the non-woven layer.

[0075] Porosity and mechanical tensile strength can be varied by controlling the heat used to calender the material, and by the usage of an engraving roll that can place apertures on the film. Glazing can be an overall surface treatment or a variable/zone application. For purposes of visual comparison only, and not for comparison to mechanical or end-use properties, the smooth glazed PLA fibrous surface resembles in appearance only the commercial product Tyvek®. The purpose of the fiber glazing (calendering) process is to eliminate the need for a separate film, and it provides a unique and advantageous method to control fluid flow in the non-woven layer with a minimum of lamination and processing effort while increasing the utility of the non-woven layer. Non-limiting examples of the range of porosity and mechanical tensile strength that can be achieved by the calendering process of the present invention are shown in exemplifications below. One of ordinary skill in the art would be able, with guidance from the teachings of the present invention, to extrapolate times and temperatures necessary for a desired porosity.

[0076] In another embodiment, a nonwoven layer can be made eliminating the need for glues and adhesive bonding, and at the same time provide, if needed, perforations that allow the purge fluids to flow into an absorbent layer. The PLA glazed surface can be treated with hydrophilic and/or hydrophobic materials to adjust for the release of the chlorine dioxide gas which is activated by contact with ambient moisture.

[0077] In some embodiments, the glazing provides a film-like outer surface with a fibrous inner structure. The film-like outer surface can be perforated, preferably via ultrasonic perforation, to provide various size channels and orifices for controlling fluid flow and adsorption. In the present invention, an engraved roller was used in the calendering process. Perforation may also be used as a means of bonding the PLA nonwoven structures to other structures. These other structures can be, but are not limited to, synthetic films, fibers, or foams, natural films, fibers, or foams, or naturally- derived films, fibers, or foams. Ultrasonic bonding and ultrasonic perforating, or roller bonding and roller perforation, both may be used to provide a bond between similar and dissimilar structures including but not limited to film to film, film to fiber, and fiber to fiber, generally employing thermoplastic materials, or materials of natural, naturally-derived, or synthetic origin, both organic and inorganic in nature.

[0078] Needle-punching can also be used advantageously to bond similar and dissimilar structures including but not limited to film to film, film to fiber, and fiber to fiber, generally employing thermoplastic materials, or materials of natural, naturally-derived, or synthetic origin, both organic and inorganic in nature. Needle-punched nonwoven structures are created by mechanically orienting and interlocking the fibers of a meltblown, spunbonded or carded web. This mechanical interlocking of the fibers is achieved with thousands of barbed felting needles repeatedly passing into and out of the web. As the needleloom beam moves up and down, the blades of the needles penetrate the fiber batting. Barbs on the blade of the needles pick up fibers on the downward movement and carry these fibers the depth of the penetration. The draw roll pulls the batt through the needle loom as the needles reorient the fibers from a predominately horizontal to almost a vertical position. The more the needles penetrate the web, the more denser and stronger the web becomes generally.

[0079] In some embodiments, perforations in the PLA glazed non-woven material can be covered by a mesh. Such a mesh can be an integral part of the nonwoven structure.

[0080] In some embodiments, the nonwoven fibers can be treated with plasticizers to soften the fibers and render them less brittle. Such plasticizers can be, but are not limited to, other flexible synthetic, natural, and naturally-derived polymers co- polymerized with the PLA, amorphous forms of PLA, silicone oils, surfactants, polyethylene glycols such as PEG-400 as well as other molecular weight ranges of PEG, glycol ethers, such as known in the trade as "Dowanol" (glycol ethers from Dow

Chemical), polyethylene oxide polymers and oligomers such as known in the trade as "Polyox ®," octylphenoxy polyethoxy ethanol (from Dow Chemical), tridecyl alcohol ethoxylates of various molecular weights and ethylene oxide content, surfactants, especially long-chain surfactants, plasticizers are used to provide compatibility to the fibers and soften them. Many conventional plasticizers are known in the art that soften polymers and lower the Tg, (the glass transition temperature).

[0081] Plasticization can also be nonconventional. For example, temperature stable antimicrobial or biocidal agents can be employed to soften the fibers. Such a material can be master batched into the polymer melt, or applied upon post-extrusion. Also, such antimicrobials and biocidal agents, can be delivered using plasticizers. Using a plasticization process, the hardness characteristics of the fibers can be controlled by, but not limited to, polymer selection, purposeful selection of plasticizer, or selection of additives, such as antimicrobial additives, which have an adjuvant plasticizer effect. The plasticizers can be hydrophilic or hydrophobic.

[0082] Suitable examples of plasticizers, lubricants and processing aids are CP- L01 from Polyvel (Hammonton, NJ) which is a PLA plasticizer specifically targeted to improving the toughness, impact and processing capabilities of PLA. Another product by Polyvel is CT-L01 , a lubricant, which improves slip characteristics while retaining other properties; it decreases PLA's high coefficient of friction and therefore reduces or eliminates adhesion between other film or metal surfaces during production. Additionally, Polyvel CT-L03 is a processing aid which raises intrinsic viscosity of PLA providing increased molecular weight and improved melt strength. Finally, Polyvel HD-L02 is an impact modifier which allows for the increase in the expansion capabilities of PLA. Many other similar products are present in the commercial polymer additive and modifier marketplace.

[0083] In some other embodiments, antimicrobial agents may be delivered to the food product. The definition of an antimicrobial according to Stedman's Medical Dictionary, 26^th edition, 1995 is "Tending to destroy microbes, to prevent (or inhibit) their multiplication or growth, or to prevent (or inhibit) their pathogenic action." In preferred embodiments, silver or silver-species, chlorine and chlorine-species may be used.

[0084] It is preferred to place "actives" in the polymer (as described and exemplified throughout the present specification) and, thus, in each fiber and/or interspersed between fibers. Traditionally, actives have been defined as chemical or physical agents that impart specific performance characteristics (as opposed to merely physical characteristics) to polymers. For example, it is current state of art to incorporate into textile products actives using specialized pharmaceuticals and natural and botanical ingredients to provide odor control. In our invention, actives are defined, at least in part, as antimicrobial ingredients which mitigate and control the propagation of pathogen in and on the polymer fibers and in the food environment. A good overview of antimicrobial actives for textile application can be seen in "Recent Advances in Antimicrobial

Treatments of Textiles, Yuan Gao and Robin Cranston, Textile Research Journal 2008; 78; 60" or the use of antimicrobial actives as agents in polymers in "US Patent

5,906,825, Polymers containing antimicrobial agents and methods for making and using same," both of which are indicative of what is known by one of ordinary skill in the art are incorporated herein by reference. [0085] However, many materials will not tolerate the heat and pressure of extrusion. For example, halogens (iodine, chlorine, bromine) and chlorides (PVC) can release corrosive gas that can rapidly attack the machinery and require expensive alloys for protection; however, silver does not present these problems. As an alternative to a polymer-additive, after the polymer fibers are formed, the PLA fibers can be treated by coating, immersion, spraying, printing or any other technique capable of transferring an ingredient or ingredients onto the fibers. The purpose of such treatment could be to promote release of the antimicrobial agent and could include, but is not limited to, water, lactic acid, lactide, organic and inorganic acids and bases, and catalysts.

[0086] This invention utilizes, but is not limited to, antimicrobial action generated in situ upon contact of the pathogen with the antimicrobial agent. The in situ, contact- based action of the present invention can be controlled via reaction chemistry or a triggering event, such as contact with moisture, or it can be constantly released thereby providing continuous antimicrobial and/or antifungal protection.

[0087] The antimicrobial agents of the present invention can function in the condensed phase, where condensed phase means a liquid or solid, or in a gaseous phase and said antimicrobial agents can be generated in situ via a chemical reaction, or used as-is, or released in a controlled fashion.

[0088] One novel and unique improvement of the present invention over the related prior art is that the present invention integrates the antimicrobial compound as a masterbatch directly into the thermoplastic (e.g., polylactic acid) fibers as part of the meltblown fiber manufacturing process with specifically tuned process variables (as exemplified below) which results in the non-woven material used in the controlled release product. Additionally, an improvement of the present invention is to be able to specifically calender (as a function of speed, pressure and temperature) the polylactic acid polymer non-woven material with the antimicrobial formulation in order to allow it to function as a controlled and sustained release delivery system.

[0089] In some embodiments, silver species that are active against antibiotic- resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Silver species are particularly attractive to providing a broad spectrum of antimicrobial activity at low concentrations with minimal toxicity toward mammalian cells. Also, silver species have a lower tendency than antibiotics to induce resistance by targeting simultaneously multiple bacterial sites.

[0090] An antimicrobial agent refers to a chemical substance that kills or inhibits the growth of bacteria, fungi, or protozoans, that is all the various types of microbial flora present in a food produce at any stage of food deterioration, including, but not limited to, normal skin flora, aerobic and anerobic gram negative bacteria, and aerobic and anerobic gram positive bacteria.

[0091] A preferred antimicrobial and antifungal agent is ionic silver, being released from a nonwoven layer material made preferably from PLA fibers.

[0092] Examples of suitable silver and silver ion-based agents include, but are not limited to, silver halides, nitrates, nitrites, selenites, selenides, sulphites, sulphates, sulphadiazine, silver polysaccharides where such polysaccharides include simple sugars to polymeric and fibrous polysaccharides, silver zirconium complexes, forms including organic-silver complexes such as silver trapped in or by synthetic, natural or naturally- derived polymers, including cyclodextrins; all compounds, inorganic or organic, that contain silver as part of the structure, where such structures can exist as a gas, solid, or liquid, as intact salts, dissolved salts, dissociated species in protic or aprotic solvents and silver species which contain the molecular morphology or macroscopic properties of materials in contact with silver whereby such materials, either organic, inorganic, and/or of biological nature, are found in various morphologies, such as crystalline or amorphous forms, or optical activities, such as d, I or meso forms, or tacticities such as isotactic, atactic, or syndiotactic, or mixtures thereof of any of the above.

[0093] The definition of silver species includes combinations of one or more of the above compositions, and includes such compositions being in a number of various physical forms or combinations of physical forms, such as, but not limited to, sheets, fibers, liquids, gases, gels, melts, beads, and the like. The definition also includes nano structures which currently is taken to mean an entity or structure with at least one dimension between 1 and 100 namometers in size. That is, both the silver or silver species is in nanomaterial form, or the entity the silver or silver species is interacting with, or combined with, is in nanomolecular form, or both the silver and silver species and the material it is interacting with is in nanomaterial form.

[0094] The term "silver" means atomic silver, Ag, element and atomic number 47, in all its oxidation states, ionization states, or isotopic forms, including any radioactive isotopes, or mixtures thereof, and physical forms, including crystal structures and morphology. The term "silver species" means all compounds, inorganic or organic, that contain silver as part of the structure, where such structures can exist as a gas, solid, or liquid, as intact salts, dissolved salts, dissociated species in protic or aprotic solvents, and can be covalently bound, ionically bound, or bound by other mechanisms known as "charge-transfer" complexes. The definition also includes clathrate compounds that involve silver or silver species as part of the structure, and also includes silver or silver containing species that exist as a result of the process of sorption, either chemical or physical sorption, meaning absorption or adsorption, where the sorptive surface can be a molecule, polymer, organic or inorganic entity such as, but not limited to, synthetic oligomers or polymers, either thermoplastic or thermoforming, natural or naturally-derived polymers, either thermoplastic or thermoforming, biodegradable and non-biodegradable polymers, either thermoplastic or thermoforming, and inorganic or organic species whose surface area provides for some sorptive effect. Examples of the latter can include, but is not limited to, charcoal, zeolites of all chemical structures, silica, diatoms, and other high-surface area materials. The definition also includes silver or silver species in all its known valence states, either organically or inorganically bound, and includes organic or inorganic materials, either gas, liquid, or solid, where the silver or silver species can "exchange" or transfer by mechanisms such as, but not limited to, ion-exchange, diffusion, replacement, dissolution, and the like including silver glass, silver zeolite, silver-acrlyic and nano-silver structures. Zeolite carrier based (the silver ions exchange with other positive ions (often sodium) from the moisture in the environment, effecting a release of silver "on demand" from the zeolite crystals) and glass based silver chemistries (soluble glass containing antimicrobial metal ions wherein with the presence of water or moisture, the glass will release the metal ions gradually to function as antimicrobial agents), are non-limiting examples of silver-ion-based agents suitable for use in the present invention.

[0095] Common forms of silver that we employ or could employ in this invention include, but are not limited to silver glasses such as CorGlaes Ag® from Giltech Limited or lonpure ® glass from Ishizuka Glass, liquid silver/acrylic Silvadur® from Dow, nano- silver SmartSilver® from NanoHorizons, silver zeolite structures such as those offered by Agion Incorporated or silver zirconium complexes such as those offered by Milliken. Other forms include organic-silver complexes such as silver trapped in or by synthetic, natural or naturally-derived polymers, including cyclodextrins. The silver can be utilized in the form of fibers, gels, including hydrogels, and foams, films, hydrocolloids, and superabsorbents. Silver is a useful material and can be associated, complexed, or bound to organic and inorganic materials, and such a list constitutes a partial cataloging of silver's use and utility. Silver, and in particular the ions of silver (Ag+, Ag++ and Ag+++) are used to reduce bacterial and fungal populations and prevent reproduction of the same. In certain studies, silver ions have been shown to control viral populations. Although the speed of control or kill is slow, hours and days, it is a powerful tool in the prevention of cross contamination, odor control and material protection. Protection can last for months or years depending on the formulation and concentration. In this application, silver may be formulated to deliver ions rapidly and consistently over the use of the product and will impart an infection-control feature in a food sachet product where pathogen replication are rampant and exceptionally difficult to control.

[0096] Any combination of the above exemplary silver and silver ion antimicrobial agents is also contemplated for use in the PLA non-woven material.

[0097] In a preferred embodiment of the present invention for the PLA non- woven material, the antimicrobial and antifungal agents are incorporated into the actual fibers of the PLA non-woven material. In this embodiment, the agents are added to the polymer prior to the formation of the polymer into fibers. In yet another embodiment the antimicrobial and antifungal agents are both incorporated into the actual fibers and interspersed between the fibers.

[0098] In other embodiments, non-silver and non-silver ion-based antimicrobial and antifungal agents are contemplated for use in the non-woven layer of the present invention. These non-silver and non-silver ion-based agents may be used in conjunction with the silver and silver ion-based agents of the present invention. One of ordinary skill in the art, based on the teachings of the present specification, can determine suitable combinations of agents depending on the fiber composition of the non-woven material. Suitable non-silver and non-silver ion-based agents are, but are not limited to, compounds containing zinc, copper, titanium, magnesium, selenium, telerium, quaternary ammonium, silicon-based (alkyltrialkoxy silanes) quaternary ammonium cadmium, mercury, biguanides, amines, glucoprotamine, chitosan, trichlocarban, triclosan (diphenyl ether (bis-phenyl) derivative known as either 2, 4, 4'-trichloro-2' hydroxy dipenyl ether or 5-chloro-2-(2, 4-dichloro phenoxyl) phenol), aldehydes, halogens, isothiazones, peroxo compounds, n-halamines, cyclodextrines, nanoparticles of noble metals and metal oxides, chloroxynol, tributyltins, triphenyltins, fluconazole, nystatin, amphotericin B, chlorhexidine, alkylated polethylenimine, lactoferrin, tetracycline, gatifloxacin, sodium hypophosphite monohydrate, sodium hypochlorite, phenolic, glutaraldehyde, hypochlorite, ortho-phthalaldehyde, peracetic acid,

chlorhexidine gluconate, hexachlorophene, alcohols, iodophores, acetic acid, citric acid, lactic acid, allyl isothiocyanate, alkylresorcinols, pyrimethanil, potassium sorbate, pectin, nisin, lauric arginate, cumin oil, oregano oil, pimento oil, tartaric acid, thyme oil, garlic oil (composed of sulfur compounds such as allicin, diallyl disulfide and dyallyl trisulfide), grapefruit seed extract, ascorbic acid, sorbic acid, calcium compounds, phytoalexins, methylparaben, sodium benzoate, linalool, methyl chavicol, lysozyme , ethylenediamine tetracetic acid, pediocin, sodium lactate, phytic acid, benzoic anhydride, carvacrol, eugenol, geraniol, terpineol, thymol, imazalil, lauric acid, palmitoleic acid, phenolic compounds, propionic acid, sorbic acid anhydride, propylparaben, sorbic acid harpin- protein, ipradion, 1 -methylcyclopropene, polygalacturonase, benzoic acid, hexanal, 1 - hexanol, 2-hexen-1 -ol, 6-nonenal, 3-nonen-2-one, methyl salicylate, sodium bicarbonate and potassium dioxide.

[0099] A novel approach to the delivery of gas has now been discovered and described herein. By using discrete amounts of reactant contained within a single- layered apparatus, the skilled practitioner can now fabricate a gas delivery apparatus that is compact, cost-effective, and safe. The present invention can be used for a variety of applications, including delivery of gas to air or water, for a variety of purposes including disinfection, deodorization, bleaching and sanitization.

[ooioo] One advantage to this approach is that the gas can now be generated without the need for mechanical equipment, thus freeing up any space such mechanical equipment would require. Another advantage is that the reactants, which can be dangerous to handle directly, are isolated from contact with the user by the layers, which enclose the reactant.

[ooioi] Another advantage is that the apparatus of the present invention does not allow for the dilution of the reactant. Because the reactant remains concentrated within the sachet, less reactant is necessary to drive the reaction to completion and the reaction is more efficient than it would be if the reactants were diluted. Furthermore, because the reaction is driven to completion, unreacted components are minimized or eliminated. The reactant concentration also minimizes unwanted by-products.

[00102] Yet another advantage is that the apparatus is small and therefore can be easily and economically shipped and administered. An additional advantage is that the apparatus can be manipulated to allow for either rapid or slow delivery of gas. Another advantage is that the apparatus can be designed to deliver gas to either a gas, e.g., air, or a liquid, e.g., water. Other advantages will be evident to the practitioner having ordinary skill in the art.

[00103] As used herein the term "sachet" means a closed receptacle for reactant. The sachet is "closed" in the sense that the reactants are substantially retained within the sachet and the sachet volume is substantially sealed around its perimeter. However, the material or materials used to construct the sachet are chosen to allow entry of the initiating agent (ambient air) and exit of the gas (chlorine dioxide) generated. The material or materials used to construct sachets are referred to herein as "sachet layers." Sachet layers typically are constructed from a planar material, such as, but not limited to, a polymeric sheet or film. Preferred materials for sachet layers are described in greater detail below. Relying upon the teaching disclosed herein, and the general knowledge in the art, the practitioner of ordinary skill will require only routine experimentation to identify one or more sachet layers and/or construct one or more sachets adapted for the purpose at hand.

[00104] As used herein the term "envelope" means a closed receptacle wherein the envelope volume is sealed substantially about its perimeter, which contains at least one sachet and allows release of the gas from the envelope. The material or materials used to construct envelopes are referred to herein as "envelope layers." Envelope layers typically comprise a planar material such as a sheet or film, including, but not limited to perforated films, non-perforated films and membranes. Preferred materials for envelope layers are described in greater detail below. Relying upon the teaching disclosed herein, and the general knowledge in the art, the practitioner of ordinary skill will require only routine experimentation to identify one or more envelope layers and/or construct one or more envelopes adapted for the purpose at hand.

[00105] Generating CIO2 traditionally requires either reaction with acid or on-site instrumentation such as an applicator or generator to generate and apply the liquid. This method is very inconvenient, relatively expensive, and requires technical expertise. For application of CI0₂ in the food industry, simple, easy to implement and inexpensive methods are necessary and hence the importance of our novel approach of a controlled CIO2 releasing sachet. This invention identifies one or more chlorine dioxide compounds (two or three part chemistries with various chlorite and weak acids in various weights and concentrations) that offer multi-day controlled release properties.

[00l06]The present invention is a sachet containing dry ingredients which, upon contact with moisture (humidity), will produce a biocidal chemical in the vapor phase. This gaseous "sanitizer" has demonstrated lethal capabilities against a broad spectrum of pathogenic micro-organisms such as viruses, parasites, bacteria and spores that cause food borne illnesses, infections, and disease.

[00107] Generation of a gas, e.g., by acid activation, is well known. For example, chlorine dioxide (CIO2) is generated from sodium chlorite and an acid, such as citric acid, in the presence of moisture as follows.

5CIO2- + 4H⁺ <→ 4CIO2 + 2H₂0 + Cl-

Specific examples of this reaction include the following.

2NaCI0₂ + Na₂S₂0₈→ 2CI0₂ + 2Na₂S0₄ 2NaCI0₂ + NaOCI + HCI→ 2CI0₂ + 2NaCI + NaOH

Alternatively, chlorine dioxide can be produced by the reduction of a chlorate, e.g., sodium chlorate or potassium chlorate, in the presence of a weak acid, e.g., oxalic acid. Generally the reaction occurs as follows.

CIO3-+ 2H⁺ + e-→ CIO2 + H₂0

For example, reduction of sodium chlorate by acidification in the presence of oxalic acid to produce chlorine dioxide can proceed as follows.

2 NaCI0₃ + H2C2O4→ 2CIO2 + 2C0₂ + 2H₂0

[00i08]The chemical combinations described herein, comprise constituents that can be varied in appropriate quantities and relative proportions to yield a controlled and sustained ClO^ gas release profile from a sachet. The chemical combination embodies a chemical oxidant, a chemical reductant, and in some cases, a component (effector) all of which are activated by their intermixing facilitated by the presence of moisture. The effector induces an electron transfer reaction between the chemical oxidant (e.g.

chlorine-containing oxidant) and the chemical reductant and makes this reaction kinetically favorable. When the chemical oxidant is a chlorine-containing compound, the effector facilitates reduction of the chemical oxidant to a chloride ion so as to provide a reaction intermediate comprising chlorine dioxide.

[00109] Other applications will be apparent to the skilled practitioner. For example, the generation of nitrogen dioxide by the acid activation of a nitrite, e.g., sodium nitrite or potassium nitrite. Alternative routes for generation of a gas, e.g., reduction of chlorates by sulfur dioxide (Mathieson Process), are well known in the art and can be utilized in accordance with the present invention.

[00110] In one aspect, the present invention features an apparatus for delivery of a gas. An exemplary embodiment of this apparatus generally includes an envelope, a sachet disposed within the envelope, and a reactant disposed within the sachet that generates a gas in the presence of an initiating agent, wherein the envelope allows release of the gas from the envelope.

[ooiii] One currently preferred embodiment of the invention features an apparatus for delivery of a gas which includes a first reactant disposed within sachet, a second reactant disposed within the sachet, and an initiating agent disposed within the frangible pouch. In this embodiment, the first reactant and the second reactant generate a gas in the presence of the initiating agent, and the envelope allows release of the gas from the apparatus. [00112] In another aspect, the present invention features a method of forming an apparatus for delivery of a gas including the steps of (a) providing a single-layer structure comprising a reactant layer centrally disposed between two sachet layers, and (b) constructing the multi-layer structure such that the two envelope layers form an envelope defined about its perimeter by the stamp, and the two sachet layers form a sachet defined about its perimeter by the construction.

[00113] In yet another aspect, the present invention features a method of delivering gas including the steps of (a) providing a multi-layer structure comprising a reactant layer centrally disposed between a sachet layer and a barrier layer, and an envelope layer disposed adjacent to the sachet layer, and (b) sealing the perimeter of the barrier layer, sachet layer and barrier layer such that the reactant is disposed in a volume defined by the sachet layer and the barrier layer.

[00114] In yet another aspect, the present invention features a method of delivering gas including the steps of (a) providing a multi-layer structure comprising a reactant layer centrally disposed between a sachet layer and a barrier layer, and (b) sealing the multi-layer structure such that the reactant is disposed in a volume defined by the sachet layer and the barrier layer.

[00115] In short, the invention provides the art with a heretofore unappreciated method and apparatus for the controlled generation of a gas.

[00116] The gas phase sachet consists of an active ingredient, sodium chlorite and inert ingredients packaged together in a proprietary device that controls the generation and release of chlorine dioxide, the anti-microbial active ingredient, when the ingredients and device are exposed to ambient moisture in the air. The product is used by placing a finished sachet inside a predetermined food container. The product then reacts with the existing humidity to release chlorine dioxide gas in a strictly controlled amount over a specific time frame. At the end of the gas release phase, the materials inside the sachet breakdown into harmless chlorides.

Composition

Sodium Chlorite

Technical Sodium Chlorite

Molecular formula: NaCI0₂

CASRN: 7758-19-2

EPA Chemical Code: 20502

Purpose: Active Ingredient

Citric Acid

CASRN: 77-92-9 and /or 5949-29-1

Purpose: Acidification Aluminum-magnesium Hydroxyl carbonate (hydrotalcite)

CASRN: 85585-93-9

Purpose: Flow Agent

Resulting Chemical Compound

Chlorine Dioxide

Molecular formula: CI0₂

CASRN: 10049-04-4

[00ll7]Thus, in an embodiment of the present invention, the invention comprises a sachet, comprising: at least one layer (i.e., backbone layer) of non-woven fibers comprising one or more biodegradable thermoplastic polymers incorporated to the superabsorbent layer and one or more silver-based or silver ion-based antimicrobial agents with the necessary mechanical properties of flexibility and robustness comprising one or more biodegradable thermoplastic polymers incorporated to one or more silver- based or silver ion-based antimicrobial agents. The silver-based or silver ion-based antimicrobial agents can be are incorporated into the non-woven fibers or interspersed between the non-woven fibers. The fibers of the non-woven layer, in an embodiment, are oriented to provide expansion due to the absorption of moisture and fluids and maintain paths for liquid-flow and air-flow, preferentially in a direction transverse or essentially traverse to an exterior surface. Further, the fibers of the present invention may be vertically lapped or spirally wound. "Vertically lapped" is defined herein as meaning that the ends of one set of fibers overlap vertically with the ends of another set of fibers, i.e., the fibers of the first set of fibers and the fibers of the second set of fibers are oriented substantially in the same direction and are overlapping to some degree. "Spirally wound" is defined herein as meaning that the fibers form substantially a helix.

[00118] Polymer means natural, naturally-derived, synthetic, biopolymers, and oligomeric species thereof, with an oligomer defines as a low molecular weight polymer, which is therefore defined as a module having two of more repeating monomeric repeating units.

[00119] In certain preferred embodiments, the addition of protease-type depolymerases and lipase-type depolymerases in the polymer or fiber, to constitute a system, can also degrade the polymer.

[00120] In a further embodiment of the present invention, construction of the biocidal sachet can include a food pad that incorporates superabsorbent technology. The usage of the one or more superabsorbent agents allows the food pad to absorb the free fluid (e.g., water, biofluids, etc.) that is frequently present in food packaging (e.g., fresh produce packaging) to improve the visual appearance of the food to the consumer. Superabsorbents are generally insoluble crosslinked polyacrylamide polymers in granular form that absorb water and fluid, but the field of superabsorbent polymers is not limited to polyacrylamide chemistry, as is known by those of ordinary skill in the art. Superabsorbents, abbreviated SAP, provide an economical means to increase fluid- holding capacity. U.S. Patent Nos. 7,732,036 and 7,799,361 (both of which are incorporated herein by reference in their entirety) teach the use of SAP technology in a food pad. Further, SAPs are available commercially. However, conventional use of SAP's do not preclude the escape of the particles from the absorbent food pad area into the food package thereby allowing the SAP to possibly come in contact with the food.

[00121] In a further embodiment of the present invention, the SAP particles are secured to either the nonwoven pad or the previously described films that contact the food surface (e.g., on the inner surface of the films facing the absorbent pad). First, for example, SAP's can be delivered to the fibrous web and to positioned between layers. They can be held in place mechanically by the fibrous web. Second, for example, any granular SAP's used in the present invention can be secured between two layers of the fibrous web and thermal calendered so as to create a compressed and mechanically bonded pad. Third, for example, any granular SAP's used in the present invention can be secured with an aqueous polyacrylic acid solution polymer and an appropriate crosslinker. Such a polyacrylic acid solution polymer is described in U.S. Patent No. 7,135,135 (incorporated herein by reference in its entirety), assigned to H.B. Fuller Licensing and Financing, Inc. , under the trade name FULATEX PD8081 H. The crosslinking agent can be an aqueous zirconium reagent or any other appropriate crosslinker described in the patent or known in the art. U.S. Patent No. 7,135,135 further describes a spray-able material that is superabsorbent. The present invention may employ the FULATEX PD8081 H as a means to secure granular superabsorbent powder dispersed in the nonwoven absorbent web, where the nonwoven preferentially comprises totally or partially a fibrous polylactic acid filament. The present invention does not preclude the use of FULATEX PD8081 H on other natural, naturally-derived or synthetic nonwoven materials or with other granular materials, especially, but not limited to, various antimicrobial and/or antifungal agents. Further, with regard to the present invention, FULATEX PD8081 H can in itself be and function as part of a multi-component active ingredient release system (i.e., a controlled release system such as that taught by the present invention). EXAMPLES

[001221 Example 1 : Creation of the PLA Layer of the Sachet

[00123] Referring now to FIGURE 1 , Grade 6202D PLA polymer pellets 100 from a provider such as NatureWorks LLC of Minnetonka, Minnesota, US is utilized from a fresh unopened bag and introduced into the mouth of a 2.5" 30:1 40-hp extruder 111 and exposed to mechanical shear and heat ranging from 325 to 425 °F as it travels through the system. Filtration followed by a gear pump 110 push the molten polymer through a heated transfer line 101 into a BIAX meltblown system at 800 to 2000 pounds per square inch (psi). Compressed air is heated to 475-525 °F and introduced into an extrusion die 102 at 10-18 psi and used to attenuate the PLA fibers through nozzles with an internal diameter of 0.012". A water and air quench 103 is provided to create the non-woven fibers 105. This includes a filtered water mist quench produced using a high-pressure piston pump and a fluid-misting system. This quench is operated at 500-1800 psi and the mist impinges the fibers as they exit the die zone and serves to cool them.

[00124] Additionally, an air quench system introduces cool outside air to the non- woven fibers 105 before they are deposited on a flat belt 109 with a vacuum source 108 below. The speed of this belt actuated by conveyor rollers 107 determines the weight of the web. For most advanced food sachet applications a non-woven layer between 10 and 1000 grams per square meter (gsm) is required. The vacuum level additionally serves to compress the web, or allow it to remain fluffy and at a low density. Calender or thermal point bonding can serve to strengthen the material non-woven layer and impart strength. An alternative is to place a lightweight (14-20 gsm) spunbond nonwoven fabric under the web of fibers to impart strength. Once the non-woven layer is calendered by a calender station 104 (shown further with regard to FIGURE 2 and described further herein below with regard to Example 2), it is directed to a windup station 106 for final packaging and assembly.

[00125] Following collection on the belt, the web is wound into a roll and delivered to a roll wind up station. Depending on the requirements of the application, this web can be unwound from the station, and passed through a series of rollers and lamination stations, to get conjoined with an equivalent web, to yield a non-woven layer with increased compressibility and mechanical characteristics. Such a web, either one layer, or two layers or multiple layers can be conveniently cut to get converted at a later stage into finished food sachet products.

[00126] As a reference for mechanical properties, the tensile strength of one 33 gsm PLA layer was measured to be 0.765 in/lbs using a Twing-Albert Tensile Tester using ASTM D5035 protocols. A 66 gsm PLA layer was measured to be 3.884 in/lbs using a Twing-Albert Tensile Tester using ASTM D5035 protocols.

[001271 Example 2: Calendering of Outer PLA Layer of the Sachet

[00128] In order to impart different properties to the outer non-woven PLA layer of the boot dryer insert calendering can be utilized. We used a BF Perkins (division of Standex Engraving, LLC, Sandston, VA) Calender Station which contained two heated rolls and two hydraulic rams. Each heated roll was filled with high temperature oil, which was heated by a separate machine. A hot oil machine controlled the temperature and the flow of oil through each zone of the Calender Station. The temperature can range from 1 10 to 550 °F. The hot oil was circulated at 30 psi through 2 inch iron pipes into a rotary valve for each zone.

[00129] The Calender Station was opened and closed by a control station which also regulated the amount of pressure used to move the hydraulic rams. This pressure can range from 1 psi to 3,000 psi and maintained the amount of force with which the Drive Roll was supported. A variable spacer between the Sunday Roll (also called an Engraved Roll) and the Drive Roll maintained the distance of one roll to the other. The spacer allowed for the thickness of the PLA and the hydraulic rams maintain that distance. FIGURE 2 shows one possible schematic representation of the process. Non- limiting specifications are given below. One of ordinary skill in the art will be able to modify these specifications based on the guidance provided by this specification.

i. Top roll, labeled Sunday Roll 200, was an engraved roll; 7 3/8" diameter by 20" length.

ii. Bottom Roll, labeled Drive Roll 202, was a smooth roll; 10" diameter by 19 1/2" length.

iii. The temperature was variable on product density and speed of the

process line. The speed can range, for example, from 1 to 200 FPM (feet per minute) with a temperature of 175 to 350 °F.

iv. The distance provided by spacer 203 between the rolls was a variable controlling thickness of the non-woven material 201 which can range from 0.5 to 0.001 inch.

[001301 Example 3: Creation of Multiple PLA Outer Layers For Sachet with Silver Antimicrobial

[00131] One PLA layer was laminated to another PLA perforated or apertured film created by uniquely calendering the PLA fibers to provide mechanical cushioning and antimicrobial action. Silver in the PLA film and the PLA non-woven layer was biocidal and slows the growth of bacteria and fungi on the non-woven layer itself. [00132] 1AWC-1 and 2AWC-1 are sample identifiers for manufactured PLA non- woven layer with PLA film prepared according to process specifications and properties shown in Table 1 . 1 AWC-1 is two layers of 50gsm melt spun PLA integrated with a formulation of silver Zeolite grade AC-10D from AglON (Wakefield, MA) coupled with silver glass grade WPA lonpure from Marubeni/lshizuka (Santa Clara, CA). 2AWC-1 is two layers of 33gsm melt spun PLA integrated with a formulation of silver Zeolite grade AC-10D from AglON coupled with silver glass grade WPA lonpure from

Marubeni/lshizuka, each are calendered to bond the two layers of PLA melt spun. Edge sealing refer to the samples heat sealed on all four edges of the film structure using a standard heat sealing bar, such as a ¼" band, impulse foot sealer (American

International Electric, Whittier, CA) at the "4" dial setting to create a sachet.

[00133] Table 1 is shown below:

Table 1

[00134] Different variations of PLA calendered film can be manufactured with different mechanical properties. For example, PLA Film 1 is calendered 33 gsm PLA integrated with a formulation of silver Zeolite grade AC-10D from AglON coupled with silver glass grade WPA lonpure from Marubeni/lshizuka at 240 °F, 40 feet per minute (fpm), at 0.001 " gap under 900 psi. PLA Film 2 is calendered 66 gsm melt spun PLA integrated with a formulation of silver Zeolite grade AC-10D from AglON coupled with silver glass grade WPA lonpure from Marubeni/lshizuka at 280°F, at 10 fpm, at 0.005" gap, under 1 ,000psi. Corresponding test data is shown below in Table 2.

[00135] If the corresponding PLA Film 1 and PLA Film 2 were uncalendered, the data is shown in Table 3 below (which clearly shows the effects of calendering):

[00136] Table 2 is shown below: Table 2

[00137] As a reference for mechanical properties, the determination of permeation is conducted according to ASTM E96/E96M-10, Water Vapor Transmission of Materials Test methodology using permeation cups by BYK-Gardner (Columbia, MD) and weigh scale by Mettler Toledo (Columbus, OH).

[00138] The size of the apertures for PLA Film 1 and PLA Film 2 were measured to be 0.022 inches in diameter. The apertures can be of a given shape (circular, diamond, etc.) as determined by the design of the engraved roll (Sunday roll).

[00139] Additional permeation characteristics can be designed with various constructions as exemplified in the Tables 3 below.

[00l40]Table 3 is show below:

Table 3

[00141] There can also be PLA calendered film calendered to each other with or without heat sealing to create a stronger or additionally functionally structure. The heat sealing can be conducted on two edges (machine web direction or machine cross direction). Additionally, the PLA calendered films can be calendered to other PLA films and heat sealed. Below in Table 4 some of the combinations of structures and the corresponding mechanical properties are shown. The heat sealing for Table 4 was conducted in the machine web direction using a standard heat sealing bar, such as a ¼" band, impulse foot sealer (American International Electric, Whittier, CA) at the "4" dial setting was used to seal the edges. Heat sealing can be conducted on all four edges to create a sachet.

[00142] Table 4 is shown below:

Table 4

[00143] A variety of layers with different densities, each providing a specific performance characteristic can be stacked, calendered and constructed to provide multiple or single PLA layer(s)having differing thicknesses and size.

[00144] Example 4: Active Structure with Polymer Additives for Lubrication for

PLA

[00l45]This is similar to Example 1 however a polymer additive or masterbatch in dry form is added into the PLA to impart lubricity. When added to the PLA at a 3.0% level, a higher volumetric throughput rate (higher density; i.e. gsm attainment) was observed while keeping the operating pressures same, indicating lower resistance to pumping. The higher volumetric throughput rate was observed by the increased rpm on the melt-pump and extruder motor. The melt additive used was CP-L01 from Polyvel Inc., a multipurpose plasticizer additive. When CT-L01 was substituted, also from Polyvel, at 3% level, lubricant or processing aide for "slip" the same throughput rate as lower extruder and meltpump speeds was observed.

[00146] The data set forth in Table 5 below, show the change in density (gsm) for different runs of PLA integrated with a formulation of silver Zeolite grade AC-10D from AglON coupled with silver glass grade WPA lonpure from Marubeni/lshizuka with different process settings and with different levels of additives.

[00147] Table 5 is shown below:

Table 5

[00148] Example 5: Active Structure with Topical Hydrophilic Treatment Added for PLA

[00l49]This is similar to Example 1 except the hydrophilic additive was in liquid form mixed into the water quench system and sprayed directly on the fibers while hot. Many surfactants are candidates however polyethylene glycol (PEG) 200-900 mw is preferred. The concentration used is based on the weight of the fibers strayed and a range of 0.05% to 2.0% has proved beneficial in promoting rapid fiber wet-out.

Additionally, the resultant fibrous web demonstrated a more rapid fluid acquisition speed. This enhanced hydrophilicity is advantageous when an absorbent article with rapid fluid uptake is desired. The liquid additive used was Lurol PP-2213 from Goulston

Technologies, Inc. and is marketed as a single-use surface hydrophilic agent into the hygiene and diaper industry. The results are dramatic as almost immediate wet-out occurs. Another product, Triton X-100 (Dow Chemical) was also tried successfully. It was applied to a 3x3 inch, 33gsm PLA non-woven layer integrated with a formulation of silver Zeolite grade AC-10D from AglON coupled with silver glass grade WPA lonpure from Marubeni/lshizuka, with a water mixture, at 1% and 0.5%. Each sample was fully submerged into a volume of water and then weighed with these results and shown in Table 6 below. [00150] Table 6 is shown below:

Table 6

antimicrobial Feature

[00l52]This is similar to Example 1 except a custom masterbatch containing a slow-release silver ion compound was incorporated to provide broad antimicrobial and antifungal performance. Several silver-releasing materials have been evaluated including, silver Zeolite grade AC-10D from AglON, silver glass grade WPA from Marubeni/lshizuka, silver zirconium, Alphasan from Milliken. In each case, a 20-30% loading in a carrier polymer was prepared and used to uniformly deliver the silver additive into the mix. One preferred silver is the silver zeolite grade AC-10D from AglON which also contains copper elements as an anti-fungal agent. Another preferred silver is the WPA lonpure silver glass powder from Marubeni/lshizuka. Particle size of less-than 5 micron was specified with an average of 2-3 microns to preclude spinneret nozzle clogging. The final concentration of silver in the meltblown fibers is dependent on the quantity of masterbatch used. In trials, up to 20% masterbatch has been processed to demonstrate an extreme loading, 5% silver by weight using nano-silver. For the performance required of medical dressings, we have found 1 to 200 ppm loadings, of actual silver by weight, to be effective. In advanced food shelf-life applications silver is highly effective as its slow release and long-term bacterial control properties match the end-use requirements. The silver can be placed in a masterbatch with PLA, or an olefin carrier. For PLA fibers, we prefer the PLA carrier simply to maintain the degradability performance. The antimicrobial action of the silver is triggered upon contact with moisture.

[00l53]To determine the efficacy of antimicrobial formulation, samples of a PLA non-woven fiber layer sheet (Lot: TP061 12012 with 94.5% PLA and 4% of masterbatch which is 80% PLA and 20% WPA lonpure silver glass powder from Marubeni/lshizuka and 1 .75% of masterbatch which is 80% PLA and 20% silver Zeolite grade AC-10D from AglON) was submitted to NAMSA (Irvine, CA) for testing utilizing the ASTM E2419 testing protocol with sample size of 1 g, target inoculums level of 1 .5-3.0 x 10⁵ CFU/mL with the organisms Klebsiella pneumonia (KP) source no 4352, Staphylococcus aureus (MRSA) source no 33591 , and Enterococcus faecalis (VRE) source no 51575. Data acquired by NAMSA is shown below in Table 7.

[00154] Below is the test data in Table 7.

Table 7

[001551 Example 7: Measuring Silver Antimicrobial Content in PLA Non-woven Material Layer

[00l56]The analysis of solid samples for elements such as silver has been much studied and each was found to have some liabilities or difficulties. Methods such as wavelength dispersive X-ray fluorescence spectroscopy (WD-XRFS), laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) as well as conventional acid digestion in a Kjeldahl flask in combination with dry ashing and microwave assisted digestion followed by atomic absorption spectrometry (AAS) are the "go to" analytical tools especially for biological and environmental samples. However, solid sample analysis affords some challenging issues for each of the aforementioned methods as described in F. Vanhaeke, et al, Spectrochimica Acta: Part B 62, (2007) pp1 185-1 194. For example, this study showed LA-ICPMS has potential for the direct analysis of solid samples but for variations in ablation efficiency which affords calibration difficulties. Similar calibration issues arise with WD-XRFS, mainly due to differences in absorption efficiency of X-rays. These authors describe having obtained accurate results for Ag determination using conventional acid digestion in a Kjeldahl flask in combination with dry ashing and microwave assisted digestion followed by AAS. Occasionally however, they noted analyte losses and/or incomplete dissolution as the source(s) of discrepancy.

[00i57]The reagents and materials for experimentation were as follows. As specified by good lab practice, only high purity reagents were employed in sample preparation. A Millipore (Billerica, MA) Milli-Q system was used to generate water of 18 ΜΩ purity. Concentrated nitic acid (HN0₃) and 30% hydrogen peroxide (H₂0₂) were obtained from Fisher Chemical (Houston, TX) and (1 mg/ml_) Ag in HN0₃was obtained from Acros Organics/Thermo Fisher Scientific (Geel, Belgium and Boston, MA) for sample digestion and calibration standard preparation, respectively. The non-woven material with silver antimicrobial was manufactured as exemplified in the examples above.

[00158] For the digestion of PLA non-woven samples, we used a HotBlock Pro Digestion System from Environmental Express (Charleston, SC). The 54-well HotBlock Pro for 50ml_ samples has an external thermocouple and an external controller to monitor and record sample temperatures. The controller also allows you to program and implement the digestion method (see below). For analysis of samples by Atomic Absorption Spectrometry, an ICE 3000 Series Flame AA Spectrometer from Thermo Fisher Scientific (West Palm Beach, FL) was used. The silver (Ag) hollow cathode lamp was purchased separately from Thermo Fisher Scientific (West Palm Beach, FL)

[00159] For digestion, we employed an adaptation of EPA Method 3050B for use with the Environmental Express HotBlock Digestion System. The 0.5g samples were each placed into a 50 mL borosilicate digestion vial to which 5 mL of a 1 :1 mixture of concentrated HN0₃ and 18 ΜΩ water is post added. The digestion vials were placed into the HotBlock unit, affixed with reflux caps and heated at 95°C for 15 min. Samples were allowed to cool and an additional 5 mL of concentrated HN0₃ was added and then heated @95°C for 30 min. This step was repeated until no brown fumes were given off by the samples. The samples were then heated for an additional 1.5 hours after which they were removed from the HotBlock Pro and completely cooled. To each of these vials was added 2-5mL of 18 ΜΩ water and 0.5mL of 30% H202 slowly. An exothermic reaction was allowed to occur for approximately 5-10 minutes and the samples were placed back in the HotBlock with the ribbed watch glasses in place. Effervescence was controlled by lifting the samples out of the HotBlock while allowing the reaction to continue. Care was taken to ensure that the samples did not overflow the vials. H₂0₂ was continually added in 0.5 mL increments until the sample remained unchanged in color (no longer than 30 minutes). Then heating was continued for a total of 2 hours.

[00160] For the analysis of samples for Flame AA, 5mL of concentrated hydrogen chloride (HCI) was added to each sample and covered with a ribbed watch glass and heated to reflux at 95 °C for 15 minutes. After cooling completely, the samples were diluted to 50 mL with18 ΜΩ water. A calibration curve was constructed on the basis of absorbance obtained for aqueous standards containing 0.5ppm, 10ppm, and 50ppm Ag in solution. [00161] Two identical sets of samples were tested to account for repeatability; they are denoted as "A" and "B" in the testing protocol.

[00l62]The sample weights and composition of materials is shown in Table 8 below. MB21 is a master-batch with of 20% silver Zeolite grade AC-10D from AglON with 80% PLA; whereas MB23 is a masterbatch with 20% silver glass grade WPA lonpure from Marubeni/lshizuka with 80% PLA.

Table 8

[00163] The results obtained from the analysis of these samples run in triplicate are presented in Table 10. These results are expressed in ppm Ag. The expected Ag content, presented in Table 9, has been calculated based upon the type of silver (WPA lonpure or AglON) and the amount added during processing. We observed good agreement between the theoretical values and the analytical results with the exception of samples 4 & 6. Sample 4 is lower than the lower end of the theoretical range in 2 of the 3 repeat samplings, while sample 6 is a bit higher than the high end of the range for all three repeat samplings.

[00164] Table 9 is shown below for theoretical Ag calculations. Because the silver zeolite (AglON) has a range of 2%-5% pure silver content, the theoretical calculations for Samples 4-6 are denoted for 2% and 5% levels individually.

Table 9

Sample # Concentration A Concentration B Prev. Concentration

(ppm) (ppm) (ppm)

1 0 0 0 2 1 .0 0.96 0.92

3 2.51 2.61 2.5

4 (2%) (5%) 1 .5 (2%) (5%) 1 .5 (2%) 0.5 (5%) 1 .4

0.50 0.50

5 (2%) (5%) (2%) (5%) (2%) 1 .5 (5%) 3.9

1 .63 4.08 1 .57 3.92

6 (2%) 1 .9 (5%) 2.9 (2%) (5%) 3.1 (2%) 1 .9 (5%) 2.9

2.02

[00l65]Table 10 is shown below for Ag determination by Flame AA.

Table 10

[00166] The data indicates that the present invention for the non-woven material layer can have a lower percentage of silver content than what is commonly in the marketplace (80 to 400 ppm) to deliver equivalent level of antimicrobial efficacy as exemplified above resulting in a product that is more cost-efficacious.

[00167] From all the samples which we have run, we tend to think that these out of range values are likely variability due to material handling and process conditions.

[001681 Example 8: Active Structure made with PolvCaprolactone Polymer

[00l69]This is similar to Example 1 , above, with the exception that

Polycaprolactone (PCL) was added to the PLA in a blend at various levels from 5% to over 70%. PCL is a naturally derived polymer with a very low melt point. When used at low levels, generally 30% and lower, it functions as a plasticizer for the PLA, a brittle polymer, and imparts lubricity and a softness to the fibers that functions to reduce breakage. This dramatic improvement is apparent even at a 2% add-on level and increases with concentration. The PLA/PCL blend can also incorporate masterbatch additives or surface finishes to modify the hydrophilicity and fluid wet-out speed. Silver can also be incorporated. The lower processing temperature of the PCL allows the use of low-temp additives but also limits the effective storage and use temperatures of the finished product. [00170] Below Table 8 shows the physical property of various PLA/PCL structures that were manufactured with different mechanical properties. For example, PLA/PCL Structure UC-1 is non-calendered 600 gsm 93%PLA with 3% CP-L01 and 3% CT-L01 and 1 % PCL run at 400 °F, 3 fpm and 1 100 psi. Corresponding test data is shown below for various combinations and permutations wherein the speed, pressure and temperature were changed.

[00171] Table 1 1 is shown below:

Table 11

[00l72]The mean is 1.277 lbs for tensile strength, 20.046% for apparent elongation and 3.063 sec for break time.

[00173] By calendering various samples, the following data shown in Table 12 was obtained:

[00174] Table 12 is shown below:

Table 12

PLA/PCL Structure 7 1 .1 17 23.799 3.593

PLA/PCL Structure 8 1 .481 10.696 1.704

PLA/PCL Structure 9 2.268 19.359 3.000

PLA/PCL Structure 10 2.221 17.755 2.750

PLA/PCL Structure 1 1 2.185 22.342 3.375

[00l75]The mean is 1.780 lbs for tensile strength, 16.779% for apparent elongation and 2.567 sec for break time.

[001761 Example 9: Fiber Diameter Influence on Performance

[00177] By varying the thru put rate of the molten polymer and the air used for attenuation, the fiber diameter and degree of polymer orientation within the fiber may be modified. Additionally, the internal diameter of the polymer nozzles, in the die or spinneret plate can be modified. In this example the polymer and thru put rate was held constant while spinneret plates with different diameters were utilized and the effect of fiber diameters was measured. Extruder zone temperatures, die-head temperatures and pressures, collector belt speed and quench air settings were optimized. Nozzle diameters ranging from 0.01 1 to 0.023 inches were evaluated and resultant changes in fluid management and physical cushioning were observed.

[00178] An experimental trial matrix and performance data are shown in Table 10 below and plotted as shown in FIGURE 3:

[00l79]Table 13 is shown below:

Table 13

[00180] Magnified photograph of fibers from 0.015 inch nozzle, yielding a 0.015 micron diameter (average measurement of 10 fibers with a standard deviation of 4 microns) fiber is shown in FIGURE 4.

[00181] Magnified photograph of fibers from 0.015 inch nozzle showing the PLA non-woven in a cross-section of the layer with fiber direction being transverse to an exterior surface; also film orientation wherein the top surface is the horizontal surface on the photograph, and the side of the insert is the vertical surface as shown in FIGURE 5.

[00182] Magnified photo of fibers from 0.,015 inch nozzle showing the PLA non- woven in a cross-section of the layer with fiber direction being transverse to an exterior surface; the partially vertical surface is the side of the layer, in an even more magnified photograph is shown in FIGURE 6.

[00183] Magnified photo of fibers from 0.015 inch nozzle showing the PLA non- woven in a cross-section of the layer with fiber direction being transverse to an exterior surface; the partially vertical surface is the side of the insert, in an even more magnified photograph is shown in FIGURE 7.

[001841 Example 10: Non-woven Fiber Material Made With Polypropylene Polymer

[00l85]This is similar to all above examples with the exception of polypropylene polymer (PP) is substituted for the PLA. The advantage of PP is a higher processing and throughput speed. PP has all the required health and safety and low-bioburden properties medical dressings require. It is also receptive to hydrophilic additives in a masterbatch or surface treatment to impart rapid fluid wet-out. Additives can easily be included in masterbatch form. A PP meltblown web can also be thermally point bonded or placed on a spunbond carrier for additional strength and can be processed in a secondary treatment step to impart a silver-containing treatment.

[00186] In this example we used ExxonMobil (Houston, TX) Achieve 6936G ultrahigh melt flow rate polypropylene at the 100% level and with additives. One distinct advantage was lower melt processing conditions when compared to PLA. Extruder and spinning temperatures in the 275 to 350 °F range were sufficient and this product and this allowed polymer additives that were heat-intolerant to be utilized.

[00187] The below table (Table 14) shows the particulars of a 3BSK-1 all PP sample manufactured on the meltblown line. 3BSK-1 consists of two 50 gsm PP melt spun layers and 25 gsm of SAP, calendered to bond the SAP between the two layers of PP. Edge sealing refer to the samples heat sealed on all four edges of the film structure using a standard heat sealing bar, such as a ¼" band, impulse foot sealer (American International Electric, Whittier, CA) at the "4" dial setting.

[00188] Table 14 is shown below

Table 14

[00189] Melt spun PP of various densities and thicknesses were calendered at a close nip under high pressure to produce a film structure. See test data below (Table 12) to see the various structures created and the performance difference between "calendered" and "uncalendered."

[00190] The 33 gsm melt spun PP was calendered at 210°F, at 10 fpm (feet per minute), at 0.001 " gap, under 1000 psi, to create "PP Film 1 "; see Table 15.

[00l9l]Table 15 is shown below:

Table 15

[00192] A 48 gsm melt spun PP was calendered at 250 °F, at 10fpm, at 0.005" gap, under 1 ,000psi, to create "PP Film 2," see, Table 16.

[00l93]Table 16 is shown below:

Table 16

[00194] Purchasing an off-the-shelf SMS polypropylene material (Green Bay Non- Wovens; Green Bay, Wl) can also be utilized. Many suitable spunbond webs are suitable for use in the present invention in view of the teaching provided in the present specification (e.g., PP, PET or PLA polymers with hydrophilic or hydrophobic finishes). In the invention, a 18-gsm and 60-gsm SMS web (spunbond/meltblown/spunbond) from Green Bay Nonwovens (Green Bay, Wl) was evaluated. This is a commodity product used in infant disposable diapers and has a hydrophilic finish. It is very strong and uniform of its lightweight. The method of construction was identical to the method described above for the PLA material.

[00i95]Table 17 below shows the mechanical properties of the SMS web tested. Table 17

[0001] Example 11 : Superabsorbent Polymer in Sachet

[0002] 3 sachets were constructed from non-woven PLA as exemplified above. The PLA film material roll (see FIGURE 11 ) was manufactured as exemplified above. Then the PLA was slit (see FIGURE 12) using a slitter re-winder such as a Deacro CSR1300C (Mississauga, ON, Canada) slitter re-winder or any other equivalent for those well versed in the art. Once the slitting was accomplished, three edges were sealed (see FIGURE 13) as described above or by using an industrial reciprocating hot and cold seal packaging unit as custom-made mod-tech Delta (Minneapolis, MN) module. With the three edges sealed, the dry chemistry powder is inserted (see

FIGURE 14) using equipment such as those by Harro Hofliger (Doylestown, PA) or equivalent for those well versed in the art. The dimensions of the sachet were 2.75 inches by 2.75 inches.

[0003] Superabsorbent polymer was placed in each of the above sachets in the following quantities: 0.5 grams, 1 .0 gram, 2 grams.

[0004] The sachets were examined to determine if any superabsorbent polymer had been able to come through the PLA fiber.

[0005] None of the sachets had "leaked" out any superabsorbent polymer.

[0006] Example 12: Determination of Chlorine Dioxide Release From Sachet

[0007] The method used to determine the chlorine dioxide (CIO2) concentration in the headspace from the chlorine dioxide (CI0₂) sachet was an adaptation of the OSHA ID-202 method for the analysis of CI0₂ in the work place air specifically modified.

[0008] Sachet was constructed from non-woven PLA as exemplified above. The dimensions of the sachet were 2.75 inches by 2.75 inches.

[0009] Sachet had 0.03 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 0.06 grams of citric acid. The chemistry was placed into the sachet after weighing it; the method of placement was manually done by hand. Given the rapidity with which the chemistry reacts with the ambient air, care was taken to be quick and efficient. Once the chemistry was placed in the sachet, the last edge of the sachet was sealed, and the entire sachet was placed into another foiled lined package with desiccant packs and sealed up.

[ooio] The sachet was placed into a 40 ml_ scintillation (headspace) vial from Cole Parmer (Vernon Hills, IL). One milliliter of 18ΜΩ Dl water from McMaster Carr (Robbinsville, NJ) was added to the headspace vial and the vial was shaken 10 times to activate the chemistry. A headspace sample of 5 ml_ was collected at 0, 5, 10, 15, 30, 60, and 90 minutes, and at 2, 3, 24, 48, and 72-hour intervals. Each headspace sample was injected into a sealed vial containing 10 mL of buffered potassium iodide (Kl) solution from Fisher Scientific (Boston, MA). One milliliter of each buffered Kl samples was diluted with an additional 4 mL of buffered Kl solution prior to ion chromatography (IC) injection. The ion chromatography tool was Dionex LC20 (Chelmsford, MA) w/ GP40 gradient pump and CD20 conductivity detector. Please refer to the OSHA ID-202 method for basic details on solutions and procedure

[http://www.osha.gov/dts/sltc/methods/inorganic/id202/id202.html].

[ooii] Table 18 below demonstrates the concentrations of headspace chlorine dioxide per ml of gas sample.

Table 18

[0012] Example 12: Live Culture Efficacy Testing of Chlorine Dioxide Sachet

[0013] Live cultures of Botrytis cinerea (Be 4-83) were acquired from ATCC (Manassas, Virginia). Four Science Stuff potato dextrose agar (PDA) plates (Austin, TX) were inoculated with 1 uL of B. cinerea; two plates with mycelial growth and two plates with spores. Two plates (one mycelia and one spore) were placed in separate sealed containers (1 gallon Ziplock®), each containing a PLA sachet as exemplified above with dimensions of 2.75 inches by 2.75 inches, with 0.03 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 0.06 grams of citric acid, and labeled, "Modified". The sachets were spritzed with 1 .0g of water to activate the chemistry. The remaining two plates were placed in separate sealed containers and labeled as "Control".

[0014] The four plates were incubated in Boekel Scientific Model 132000M (Feasterville, PA) incubator at 26 °C for 5 days.

[0015] New mycelia growth, on the control, was noted after 24 hours of incubation.

[0016] The B. cinerea spores from the chlorine dioxide sachet treated plates were cultured and replated on fresh PDA plates and incubated in Boekel Scientific Model 132000M (Feasterville, PA) incubator for 2 days at 26 °C to confirm eradication.

[0017] Example 13: Efficacy of Chlorine Dioxide Sachet in Bottom Of Strawberry Clamshells

[0018] 1 lb Driscoll's (Salinas, CA) strawberry clamshells which were freshly picked and packaged were acquired. On the average there are 16 fruits per 1 lb clamshell. The dimensions of the strawberry clamshell are 7 inches x 3.25 inches x 3 inches with vent holes present to allow the strawberry fruit to "breathe", take full advantage of the cold chain storage temperatures and not create condensation in the package.

[0019] PLA sachet as exemplified above with dimensions of 3 inches by 5 inches, with 0.03 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 0.06 grams of citric acid, was manufactured and placed in bottom each clamshell as exemplified above. See FIGURE 8.

[0020] Four clamshells were "saran-wrapped" and placed in refrigeration at 34 °F for 4 days. On the 5^th day, the clamshells were extracted from the Lab Line Environeers Inc (Melrose Park, IL) refrigerator and placed at ambient temperature (70 °F) and humidity (85%) (measured with Taylor Humiguide, Las Cruces, NM) for two days. After the second day at room temperature, the fruit was evaluated for mycelia growth, discoloration, and membrane leakage. Each individual strawberry was evaluated for the above criterion, graded and data logged. Mycelial growth is denoted as the presence of white filaments on the surface or around the calyx of the strawberry fruit. Discoloration is any loss of color as manifested by yellowing or whitening on the surface of the strawberry fruit. And membrane leakage is when the outside layer of the strawberry fruit shows the first incidence of "mushy" or starts to exhibit tissue rot and spoilage.

[0021] See Table 19 below for results

Table 19

[0022] It is clearly observed the presence of the chlorine dioxide was able to retard mold propagation and prohibit to a large degree the presence of membrane leakage.

[0023] Example 14: Efficacy of Chlorine Dioxide Sachet in Top and Bottom Of Strawberry Clamshells

[0024] 1 lb Driscoll's (Salinas, CA) strawberry clamshells which were freshly picked and packaged were acquired.

[0025] PLA sachet as exemplified above with dimensions of 3 inches by 5 inches, with 0.03 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 0.06 grams of citric acid, was manufactured and placed in top and bottom each clamshell as exemplified above.

[0026] Four clamshells were "saran-wrapped" and placed in refrigeration at 34 °F for 4 days. On the 5^th day, the clamshells were extracted from the Lab Line Environeers Inc (Melrose Park, IL) refrigerator and placed at ambient temperature (70 °F) and humidity (85%) (measured with Taylor Humiguide, Las Cruces, NM) for two days. After the second day at room temperature, the fruit was evaluated for mycelia growth, discoloration, and membrane leakage. Each individual strawberry was evaluated for the above criterion, graded and data logged; definition of the criterion was similar to the exemplification above.

[0027] See Table 20 for results.

Table 20

[0028] It is clearly observed that the chlorine dioxide has strong efficacy in retarding the onset of mold on the strawberry fruit. However, because of the large amount of chlorine dioxide gas that was released the incidence of membrane leakage was greater than the control condition and the onset of discoloration was observed.

[0029] Example 15: Efficacy of Chlorine Dioxide Sachet Superabsorbent Polymer in Strawberry Clamshells

[0030] 1 lb Driscoll's (Salinas, CA) strawberry clamshells which were freshly picked and packaged were acquired.

[0031] PLA sachet as exemplified above with dimensions of 2.75 inches by 2.75 inches, with 0.03 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 0.06 grams of citric acid, was manufactured as exemplified above.

[0032] Another PLA sachet as exemplified above with dimensions of 3 inches by 5 inches with 2 grams LiquiBloc^® 2G-1 10 from Emerging Technologies (Greensboro, NC) and 1 gram Fisher Scientific calcium chloride (Boston, MA and Houston, TX) was manufactured.

[0033] Four clamshells were "saran-wrapped" and placed in refrigeration at 34 °F for 4 days. On the 5^th day, the clamshells were extracted from the Lab Line Environeers Inc (Melrose Park, IL) refrigerator and placed at ambient temperature (70 °F) and humidity (85%) (measured with Taylor Humiguide, Las Cruces, NM) for two days. After the second day at room temperature, the fruit was evaluated for mycelial growth, discoloration, and membrane leakage. Each individual strawberry was evaluated for the above criterion, graded and data logged; definition of the criterion was similar to the exemplification above.

[0034] The results of the testing are shown in Table 21 below.

Table 21

[0035] From the results it is clear to see that the "CDS - W12152" offered a reduction in the mold propagation whereas also positively influencing the reduction of membrane leakage. Also no discoloration was observed which is of importance for the consumer purchasing experience and the marketing of the product.

[0036] Example 16: Efficacy of Chlorine Dioxide Sachet in Strawberry

Clamshells In Top Of Flats For Pallet Application [0037] Four cardboard flats of strawberries, containing eight (8) 1 lb clamshells by DriscoH's (Salinas, CA), were purchased from a local grocer; it is estimated that they were 4-7 days postharvest. Each flat is 18 inches by 14 inches.

[0038] Each PLA sachet was 7.5 inches by 4.5 inches and was manufactured as exemplified above. See FIGURE 9.

[0039] One specific chemistry was utilized to determine a dose response of B. cinerea infection to chlorine dioxide as shown in Table 22 below. The chemistry shown below is for each sachet; there are a total of eight (8) sachets per cardboard flat.

Table 22

[0040] Total of eight (8) sachets per cardboard flat were placed on the top of the clamshells.

[0041] Two cardboard flats were placed on top of each other; this set-up constituted one test condition ("PFS Mod2"). The two cardboard flats together were placed in a 1 .5 mil thick polyethylene bag which was then flushed with 80% nitrogen, 15% carbon dioxide and 6% oxygen to implement a standard industry modified atmosphere (MAP) environment and then sealed up. Gas composition was measured using Quantek Model 907 Modified Atmosphere Packaging gas analyzer. The gas flushing was accomplished by connecting up the gas tanks with flowmeters to a manifold with the output connected to a ball valve which delivered the requisite combination of gas.

[0042] Together with the test conditions, a "control" ("PFS Control") was also created in the same method as described above with two stacked flats, wherein there were no sachets placed.

[0043] The stacked cardboard flats were placed in refrigeration at 34 °F for 4 days. On the 5^th day, the clamshells were extracted from the Lab Line Environeers Inc (Melrose Park, IL) refrigerator and placed at ambient temperature (70 °F) and humidity (85%) (measured with Taylor Humiguide, Las Cruces, NM) for two days. After the second day at room temperature, the fruit was evaluated for mycelia growth, discoloration, and membrane leakage. Each individual strawberry was evaluated for the above criterion, graded and data logged.

[0044] Results demonstrate differing levels of efficacy depending on the chemistry. Table 23 below shows the data. Table 23

[0045] The PFS Mod 1 resulted in 47 out of 407 berries having incidence of mold (1 1 .5%) which is lesser than the control. Also there was lesser incidence of membrane leakage and no change in the coloration of the strawberry fruit.

[0046] The data clearly indicates that chlorine dioxide sachets placed on the outside top of the clamshells has the relevant and required efficacy in retarding the propagation of mold.

[0047] Example 17: Efficacy of Chlorine Dioxide Sachet in Strawberry

Clamshells In Bottom Of Flats For Pallet Application

[0048] Eight cardboard flats of strawberries, containing eight (8) 1 lb clamshells by DriscoH's (Salinas, CA), were purchased from a local grocer; it is estimated that they were 4-7 days postharvest. Each flat is 18 inches by 14 inches.

[0049] Each PLA sachet was 7.5 inches by 4.5 inches and was manufactured as exemplified above.

[0050] Three different chemistries were utilized to determine a dose response of B. cinerea infection to chlorine dioxide as shown in Table 24 below. The chemistry shown below is for each sachet; there are a total of eight (8) sachets per cardboard flat.

Table 24

[0051] Total of eight (8) sachets per cardboard flat were placed on the bottom of the clamshells; see FIGURE 10.

[0052] Two cardboard flats were placed on top of each other. Each test setup described in Table 24 constituted one test condition with the two cardboard flats. The two cardboard flats together were placed in a 1.5 mil thick polyethylene bag which was then flushed with 80% nitrogen, 15% carbon dioxide and 6% oxygen to implement a standard industry modified atmosphere (MAP) environment and then sealed up. Gas composition was measured using Quantek Model 907 MAP gas analyzer. The gas flushing was accomplished by connecting up the gas tanks with flowmeters to a manifold with the output connected to a ball valve which delivered the requisite combination of gas.

[0053] Together with the test conditions, a "control" ("PFS Control") was also created in the same method as described above with two stacked flats, wherein there were no sachets placed.

[0054] The stacked cardboard flats were placed in refrigeration at 34 °F for 4 days. On the 5^th day, the clamshells were extracted from the Lab Line Environeers Inc (Melrose Park, IL) refrigerator and placed at ambient temperature (70 °F) and humidity (85%) (measured with Taylor Humiguide, Las Cruces, NM) for two days. After the second day at room temperature, the fruit was evaluated for mycelia growth, discoloration, and membrane leakage. Each individual strawberry was evaluated for the above criterion, graded and data logged.

[0055] Results demonstrate differing levels of efficacy depending on the chemistry. Table 25 below shows the data.

Table 25

[0056] Every modification in this test series showed significant control over the inhibition of mycelia growth; the pad having higher dose chemistry proved superior results among all. While the two lower doses (PFS Mod 1 1 and PFS Mod22) reduced the mold count by 33% and 31 .4%, respectively, the sachet containing the greater amount of chemistry (PFS Mod 3) was able to a reduction of 47.7%. The mold infected berry total for PFS Mod 33 modification was 15.5% of the 8 lbs. of berries compared to the 63.2% of the control.

[0057] See Figures 21 through Figures 25 for results of the test.

[0058] The test data clearly indicated that the chlorine dioxide sachets on the outside bottom of the clamshells have the relevant and required efficacy in retarding the propagation of mold, with the different levels of requisite chemistry offering a range of performance. [0059] Example 18: Efficacy of Chlorine Dioxide Sachet in Jute Fiber Bales for Mold Mitigation

[0060] PLA sachet as exemplified above with dimensions of 6 inches by 8 inches, with 2 grams of sodium chlorite and hydrotalcite in 4:1 ratio and 4 grams of citric acid, was manufactured. Each PLA sachet was placed in a foil-lined pack (Lewis Label, Fort Worth, TX) which was then heat sealed. The manufacturing of the PLA sachet and insertion into the foil pack were done in-situ in an atmosphere controlled manufacturing line (Selective Micro Technologies, Dublin, OH) in order to ensure the sachets did not release chlorine dioxide gas.

[0061] Three jute bales, each of 12 lb weight, were located in Hyderabad, India. The bales were damp and moist as they were brought from the field. Each bale was wrapped in commercial polyethylene wrap with a nominal specification of nominal weight of 14-20 gram per square meter. Pore size of the polyethylene wrap can range from 0.1 to 10 microns and the water vapor transmission rate WVTR can be 2000 - 5000 grams/m2/24hr (ASTM E96-2000 Desiccant). The bales were simply wrapped cylindrically and then top to bottom but are not hermetically sealed.

[0062] Three sample sets of jute bales wrapped in the polyethylene wrap were organized. Sample A was the jute bales with four (4) of the PLA sachets. Sample B was the jute bales with two (2) of the PLA sachets. Sample C was the jute bales with no sachets and constituted the control.

[0063] The PLA sachets were taken out of the foil pack and immediately placed in the bottom of the jute bales. The polyethylene wrap was slightly parted to allow ingress to the jute bales and after insert of the sachet, the ingress point was re-wrapped. Relative humidity was measured to be 15% and the temperature was 30 °C. This constituted the start of the test.

[0064] After one week (7 days) the samples were examined for fungal growth by opening up the polyethylene wrap and conducting a close-up visual analysis. Sample A and Sample B are free from any fungal growth and foul smell. Sample C had a foul smell and had a visible white to blackish colonies of fungal growth seen very clearly.

[0065] After ten (10) days the samples were examined for fungal growth by opening up the polyethylene wrap and conducting a close-up visual analysis: Sample A and Sample B had minimal fungal growth and no odor, whereas Sample C has significant fungal growth together with the foul smell.

[0066] The testing was continued for a total of 35 days. Plate dilution method with Martin's Rose Bengal agar plate was used to test the fungal colonies on the samples. The method is described below. [0067] The standard plate count is a reliable method for enumerating bacteria and fungi. A set of serial dilutions is made, a sample of each is placed into a liquefied agar medium, and the medium poured into a petri dish. The agar solidifies, with the bacterial cells locked inside of the agar. Colonies grow within the agar, as well as on top of the agar and below the agar (between the agar and the lower dish). The procedure described above produces a set of pour plates from many dilutions, but spread plates (sample spread on top of solidified agar) can be used also. The agar plate allows accurate counting of the microorganisms, resulting from the equal distribution across the agar plate. This cannot be done with a fluid solution since: 1 ) one cannot identify purity of the specimen, and 2) there is no way to enumerate the cells in a liquid.

[0068] The standard formula is:

colony count (CFUs) on an agar plate

total dilution of tube (used to make plate for colony count) X volume plated

Three values are needed to solve the above; a colony count from the pour or spread plates, a dilution factor for the dilution tube from which the countable agar plate comes, and the volume of the dilution that was plated on the agar plate.

[0069] The protocol is as follows:

Step 1 : Determine the appropriate plate for counting: Look at all plates and use the total dilution for the tube from where the plate count was obtained. If duplicate plates (with same amount plated) have been made from one dilution, average the counts together.

Step 2: Determine the total dilution for the dilution tubes:

Dilution factor = amount of specimen transferred divided by the total volume after transfer [amount of specimen transferred + amount of diluent already in tube]. dilution factor for a tube = amount of sample

volume of specimen transferred + volume of diluent in tube

Determine the dilution factor for each tube in the dilution series. Multiply the individual dilution factor for the tube and all previous tubes. Hence,

total dilution factor = previous dilution factor of tube X dilution of next tube STEP 3: Determine the amount plated (the amount of dilution used to make the particular pour plate or spread plate) and proceed to make calculations.

[0070] See Table 25 for results on the fungal colony count.

[0071] The embodiments of the invention described above are intended to be merely exemplary; numerous variations and modifications will be apparent to those skilled in the art. All such variations and modifications are intended to be within the scope of the present invention as defined in any appended claims.

Claims

What is claimed:

1 . A biocidal sachet for food safety, said sachet comprising:

at least one layer of non-woven fibers including one or more biodegradable, bioresorbable thermoplastic polymers and one or more antimicrobial agents, said at least one layer forming an envelope, said fibers being oriented to maintain paths for liquid and gas flow within said at least one layer, said paths being substantially transverse to an exterior surface of said envelope;

chlorine dioxide release chemistry retained within said envelope, said chemistry including a dry composition provided to release chlorine dioxide gas when in contact with ambient air; and

a bioresorbable, biodegradable hydrophilic surface coating on a substantial number of said fibers, said coating providing an adjusted release of said chlorine dioxide gas.

2. The sachet as claimed in Claim 1 , wherein said fibers are oriented to provide compression resistance.

3. The sachet as claimed in Claim 1 , further including a food pad formed from one or more superabsorbent polymers.

4. The sachet as claimed in Claim 1 , wherein said antimicrobial agents are silver- based agents selected from a group consisting of silver halides, nitrates, nitrites, selenites, selenides, sulphites, sulphates, sulphadiazine, silver polysaccharides, silver zirconium complexes, or mixtures thereof.

5. The sachet as claimed in Claim 1 , wherein said antimicrobial agents are silver ion-based agents selected from a group consisting of Ag-ion, zeolite-Ag, glass-Ag and nano-silver.

6. The sachet as claimed in Claim 1 , wherein said non-woven fibers are formed from one or more of polylactic acid, polylactide, polyglycolide, poly-L-lactide, poly-DL- lactide.

7. The sachet as claimed in Claim 1 , wherein said thermoplastic polymer is polylactic acid (PLA).

8. The sachet as claimed in Claim 3, wherein said food pad includes a surface film.

9. The sachet as claimed in Claim 8, wherein said surface film is formed by calendering non-woven material.

10. The sachet as claimed in Claim 9, wherein said surface film includes apertures.

11 . The sachet as claimed in Claim 9, wherein said surface film is a contiguous surface and free of apertures.

12. The sachet as claimed in Claim 8, wherein said surface film is a biodegradable thermoplastic polymer hydrophilic film formed from one or more of cellulose, alginate, gums, starch, chitosan, ethylene glycol, poly-oxethylene, and polylactic acid.

13. The sachet as claimed in Claim 8, wherein said surface film is a biodegradable thermoplastic polymer hydrophobic film formed from one or more of polylactic acid, polylactide, polyglycolide, poly-L-lactide, poly-DL-lactide or copolymers thereof.

14. The sachet as claimed in Claim 8, wherein said surface film and said food pad are calendered together.

15. The sachet as claimed in Claim 8, wherein said surface film and said food pad are heat sealed together.

16. The sachet as claimed in Claim 1 , wherein said fibers are vertically lapped or spirally wound.

17. The sachet as claimed in Claim 3, wherein said food pad includes one or more antimicrobial and antifungal agents.

18. The sachet as claimed in Claim 1 , wherein said antimicrobial agents are released upon contact of moisture with said non-woven fibers.

19. The sachet as claimed in Claim 8, wherein said surface film and said food pad are layered in multiplicities.

20. The sachet as claimed in Claim 1 , wherein said sachet provides extended shelf- life of strawberries, tomatoes, blueberries and raspberries upon placement of said sachet within respective containers thereof.

21 . The sachet as claimed in Claim 1 , wherein said sachet mitigates, retards and kills mold pathogens on organic fibers.

22. The sachet as claimed in Claim 1 , wherein said dry composition includes

an alkali metal chlorite salt in an amount from 25% by weight to 35% by weight,

a solid acid source in an amount from 45% by weight to 60% by weight, and

an effector compound in an amount from 1 % by weight to 10% by weight.

23. The sachet as claimed in Claim 22, wherein said dry composition includes a maximum amount of effector compound of 10% by weight.

24. The sachet as claimed in Claim 22, wherein said dry composition includes a maximum amount of effector compound of 8% by weight.

25. The sachet as claimed in Claim 22, wherein said effector compound includes Hydrotalcite.

26. The sachet as claimed in Claim 22, wherein said alkali metal and said solid acid are uncoated.

27. The sachet as claimed in Claim 22, wherein said dry composition excludes a source of free chlorine.

28. The sachet as claimed in Claim 22, wherein said alkali metal include chlorite salts selected from a group consisting of sodium chlorite, potassium chlorite and lithium chlorite.

29. The sachet as claimed in Claim 22, wherein said solid acids include acids selected from a group consisting of citric acid and its mono- and di- sodium salts, sodium hydrogen sulfate, sodium di-hydrogen and mono-hydrogen phosphates, oxalic acid and salts thereof, ascorbic acid and salts thereof, salicylic acids and salts thereof, and acid impregnated zeolites.