Composite Materials for Cleaning and Agriculture Applications

Abstract

A composite material for food contact applications includes an absorbent layer and a non-absorbent layer, the absorbent layer having a textured surface for absorbing and trapping liquids, for example, oil, grease, or water, and the non-absorbent layer having an oleophobic surface that acts as an oil and grease specific liquid barrier. The material further includes one or more lamination layers. The lamination layer acts as a general liquid barrier between the absorbent layer and non-absorbent layer. This additional liquid barrier enhances the liquid repelling effect of the non-absorbent layer to more effectively trap liquids in the absorbent layer, thereby preventing liquids from seeping through the material onto an external surface.

Claims

1. An absorbent pad comprising: a composite material having multiple layers configured to absorb liquids in one side, trap liquids in the absorbent side, and prevent liquids from reaching the non-absorbent side of the material opposite the absorbent side, the composite material comprising: an absorbent layer having a textured surface configured to absorb liquids from a wet surface; and a non-absorbent layer fixed to at least one surface of the absorbent layer, the non-absorbent layer forming a liquid barrier between the absorbent layer and the non-absorbent layer, the non-absorbent layer comprising: a water resistant material for preventing water, cleaning solutions, soaps, and other polar liquids from seeping through the composite material; and a oil and grease resistant material for preventing oil, grease, surfactants, cleaning agents, and other organic liquids from seeping thorough the composite material.

2. The absorbent pad of claim 1, wherein the composite material further comprises a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a second liquid barrier between the absorbent layer and the non-absorbent layer.

3. The absorbent pad of claim 1, wherein the textured surface comprises a system of ridges and valleys, the ridges positioned on a surface of the absorbent layer to improve the absorbent layer's ability to absorb liquids from a food surface, the valleys positioned on a surface of the absorbent layer to improve the absorbent layer's ability to trap liquids.

4. The absorbent pad of claim 1, wherein the composite material further is compostable and at least 90% bio-degradable within 84 days.

5. The absorbent pad of claim 4, wherein the composite material meets the 99% biodegradable composition requirement of the ASTM D6868-11 standard.

6. The absorbent pad of claim 1, wherein the absorbent layer further comprises at least one sheet of 5 lb to 55 lb basis weight paper, each sheet having a thickness ranging from 1.0 mils to 7.0 mils, a Sheffield porosity ranging from 150 units to 300 units, and a moisture percentage ranging from 5.0% to 7.5%.

7. An agricultural material comprising: a composite material having multiple layers configured to absorb liquids in one side, trap liquids in the absorbent side, and prevent liquids from reaching the non-absorbent side of the material opposite the absorbent side, the composite material comprising: an absorbent layer having a textured surface configured to absorb liquids from a wet surface; and a non-absorbent layer fixed to at least one surface of the absorbent layer, the non-absorbent layer forming a liquid barrier between the absorbent layer and the non-absorbent layer, the non-absorbent layer comprising: a water resistant material for preventing water and other polar liquids from seeping through the composite material.

8. The material of claim 7, wherein the composite material further comprises a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a second liquid barrier between the absorbent layer and the non-absorbent layer.

9. The material of claim 7, wherein the composite material further comprises a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a system of pockets between the absorbent layer and the non-absorbent layer.

10. The material of claim 9, wherein the system of pockets is configured to store a material selected from the group consisting of air, absorbed liquid, plant nutrients, seeds, fertilizer, pesticides, herbicides, and combinations thereof.

11. The material of claim 7, wherein the composite material further is compostable and at least 90% bio-degradable within 84 days.

12. The material of claim 7, wherein the composite material meets the 99% biodegradable composition requirement of the ASTM D6868-11 standard.

13. The material of claim 10, wherein the liquid barrier seals water inside the composite material so that it can be absorbed by the seeds for germination and plant growth.

14. The material of claim 7, wherein the textured surface comprises a system of ridges and valleys, the ridges positioned on a surface of the absorbent layer to improve the absorbent layer's ability to absorb liquids from a food surface, the valleys positioned on a surface of the absorbent layer to improve the absorbent layer's ability to trap liquids.

15. A seed paper comprising: a composite material having multiple layers configured to absorb liquids in one side, trap liquids in the absorbent side, and prevent liquids from reaching the non-absorbent side of the material opposite the absorbent side, the composite material comprising: an absorbent layer having a textured surface configured to absorb liquids from a wet surface; and a non-absorbent layer fixed to at least one surface of the absorbent layer, the non-absorbent layer forming a liquid barrier between the absorbent layer and the non-absorbent layer, the non-absorbent layer comprising: a water resistant material for preventing water and other polar liquids from seeping through the composite material, the composite material further comprising: seeds infused in a least one of the absorbent layer or nonabsorbent layer.

16. The seed paper of claim 15, wherein the composite material further comprises a lamination layer applied to at least one surface of the absorbent layer, the lamination layer joins the absorbent layer to the non-absorbent layer to create a system of pockets between the absorbent layer and the non-absorbent layer.

17. The seed paper of claim 15, wherein the textured surface comprises a system of ridges and valleys, the ridges positioned on a surface of the absorbent layer to improve the absorbent layer's ability to absorb liquids from a food surface, the valleys positioned on a surface of the absorbent layer to improve the absorbent layer's ability to trap liquids.

18. The seed paper of claim 16, wherein the system of pockets is configured to store a material selected from the group consisting of air, absorbed liquid, plant nutrients, fertilizer, pesticides, herbicides, and combinations thereof.

19. The seed paper of claim 15, wherein the composite material further is compostable and at least 90% bio-degradable within 84 days.

20. The seed paper of claim 15, wherein the composite material meets the 99% biodegradable composition requirement of the ASTM D6868-11 standard.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0062] A full and complete description of the present storage system is provided herein with reference to the appended figures, in which:

[0063] FIG. 1 is a top plan view of a pizza-blotting composite, according to a first aspect herein;

[0064] FIG. 2 is a cross-sectional view of the pizza-blotting composite of FIG. 1, as taken along line II-II of FIG. 1;

[0065] FIG. 3 is a perspective view of a pizza box assembly containing the pizza-blotting composite of FIG. 1, according to another aspect provided herein;

[0066] FIG. 4 is a perspective view, partially broken away, of a pizza box assembly containing the pizza-blotting composite of FIG. 1, according to yet another aspect provided herein; and

[0067] FIG. 5 is a perspective view, partially broken away, of a pouch-like container for storing the composite and distributing it to consumers with the purchase of a food item, such as pizza.

[0068] FIG. 6 is a picture of a baking sheet that was used to cook bacon at 450° F. The darker color on the sustainable paper composite inside a pizza box assembly after it has absorbed excess nutrients from the bottom of a cooked pizza. The wicking effect of the sustainable composite is clearly visible from the photograph.

DETAILED DESCRIPTION

[0069] Reference is now made to the drawings for illustration of various embodiments of the composite material and food packaging assembly. While the discussions herein refers to a round composite configured to fit inside a pizza box assembly, it should be understood that the material may be made in any shape, as needs dictate, for example, to accommodate rectangular pizzas or to cover the top or bottom of a square or rectangular pizza box. The composite material may also be integrated into any type of food packaging, for example, bags, trays, boxes, plates and other dishes, wrappers, foils, or cartoons. Further, although the discussion herein focuses on absorbing oil from pizza surfaces, it should be understood that the material described herein is equally well suited for absorbing oil and/or grease from other dishes, such as lasagna, fries, nachoes, burritos, tacos, fried rice, stir fry, macaroni and cheese, pasta, fried noodles, fried chicken, hot dogs, burgers, bbq, popcorn, and other messy foods.

[0070] FIG. 1 is a pizza-blotting embodiment 10 of the composite material having an absorbent layer 12 joined to a non-absorbent layer 14. As illustrated, the composite 10 has a perimeter edge 16, which results from the joining of the absorbent layer 12, and the non-absorbent layer 14. The layers 12, 14 may be joined by any suitable means, including, but not limited to, and adhesive, film lamination, seaming, embossing, quilting, and surface bonding. In embodiments with lamination, a degradable lamination may be applied to at least one surface of the absorbent layer, non absorbent layer, or both. The lamination layer may be placed between the absorbent layer and non aborbant layer or added to an exterior surface of the absorbent layer or non absorbent layer. The composite 10 is dimensioned to cover a substantial portion of a surface of a pizza or other take out food and, accordingly, may be provided in a number of different sizes to accommodate foods of different sizes.

[0071] The absorbent layer 12 may be made of any suitable material that is capable of absorbing oil or grease in significant quantities. Such materials include, but are not limited to, bi-component micro-fibers, biodegradable fibers, bleached fibers, cellulosic fibers, sulphite bleached fibers, and kraft bleached fibers. The material of the absorbent layer 12 may include materials that are oleophilic, meaning that they have an affinity for oils and grease but not water. The absorbent layer 12 is FDA approved for food contact applications including manufacturing, packaging, processing, preparing, treating, cooking, packing, transporting, or holding foods. The layer is low-linting, such that absorbent layer 12 does not leave lint on the food (e.g. pizza) after contact.

[0072] Inn one example, the absorbent layer 12 is a grade of crepe paper comprising a textured surface. The absorbent layer further is a 99% biobased material that is fluorine free, non-biotoxic, and safe for food contact applications. The surface of the absorbent layer is textured to absorb and trap liquid. In one example, the textured surface includes ridges and valleys. The ridges provide a capillary force for wicking liquid from food surfaces and the valleys trap absorbed liquid the absorbent layer and in a system of pockets between the absorbent layer and a lamination layer.

[0073] The paper material comprising the absorbent layer further meets the 99% biodegradable composition requirement of the ASTM D6868-11 compostability standard. The absorbent layer may comprise one or many sheets of 5 lbs to 55 lbs basis weight paper having a thickness of 1.0 mils to 7.0 mils and a Sheffield porosity of 150 to 300 units. The absorbent layer further has an auto ignition temperature greater than 400° F. and a moisture percentage between 5.0% and 7.5%. The low moisture percentage minimzes paper curl and the ignition temperature above 400° F. allows the material to be used in high temperature cooking applications.

[0074] The non-absorbent layer 14 (seen in FIG. 2) may be made of any suitable non-absorbent material that is not permeable by oils or grease. Such materials include oil and grease resistant papers (OGR), oleophobic fiber webs, polymeric films, and liquid barrier coatings. Advantageously, when the non-absorbent layer 14 is made of a flexible OGR paper, the composite 10 may have a desirable degree of malleability, such that the composite may be crumpled after use for convenient disposal without the user having to contact the oil-soaked absorbent layer 12.

[0075] In one example, the non-absorbent layer is and oil and grease resistant (OGR) material having a kit level between 2 and 9. The non-absorbent layer is further fluorine free, non-biotoxic, and safe for food contact applications. The non-absorbent layer has a flash point above 400° F. and repels fats, oil, and grease (FOG), water, and other liquids.

[0076] In a composite material, the non-absorbent layer is laminated to at least one surface of the absorbent layer to form a liquid barrier between the absorbent layer in contact with a food surface and the non-absorbent layer in contact with an external surface including a cooking surface, a customer holding food, or a recyclable material such as corrugated cardboard. The liquid barrier may repel water, polar liquids, oil, grease, organic liquids, and mixtures thereof. The liquid barrier allows a first portion of the composite material to absorb and trap liquid and a second portion to prevent liquid from seeping through the first portion.

[0077] In a preferred example, the non-absorbent layer is a compostable OGR paper material having over 90% biobased content paper. The non-absorbent layer meets the 99% biodegradable compostiion requirement of the ASTM D6868-11 compostability standard and contains no petroleum based polymers. In an another example, the non-absorbent layer is a liquid barrier coated material that repels OGR, water, and other liquids. The non-absorbent layer contains petroleum based polymer materials including, high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ultra low density polyethylene (ULDPE), polyhydroxyalkanoate (PHA), polyglycolic acid (PGA), polyethylene terephthalate (PET), polypropylene (PP), polystyrene, and polyvinyl chloride (PVC).

[0078] The lamination layer 18, joins the absorbent layer 12 to the non-absorbent 14 layer. The lamination layer provides a liquid barrier between the absorbent layer and the nonabsorbent or aborbant layers. The lamination layer comprises a non-biotoxic water based polymer emulsion coating with a flash point greater than 400° F. The lamination layer is applied as a surface coating to at least one of the absorbent layer or non-absorbent layer. In this example, the lamination layer forms a second liquid barrier between the absorbent layer and the non-absorbent layer. The additional liquid barrier enhances the composite material's ability to trap liquids in the absorbent layer by creating a system of pockets between the absorbent layer and the lamination layer. The composite material stores liquid in the pockets to prevent absorbed liquids from seeping through top layers of the composite material into the non-absorbent layer.

[0079] By bonding to the ridges on the surface of the absorbent layer, the lamination layer forms a seal over the space between the valleys and ridges on the lamination layer. This seal creates a network of pockets for holding absorbed liquid between the absorbent layer and the lamination layer. The liquid barrier prevents pooling by compressing liquid into the pockets between the sealed top surface of the ridges and the bottom surface of valleys in the absorbent layer. Additionally, by compressing absorbed liquid in the pockets, the liquid barrier formed by the lamination layer creates a wicking effect that draws absorbed liquids across the surface of the absorbent layer to unsaturated areas. The lamination layer allows the composite material of this invention to trap liquid in the absorbent layer better than conventional materials because it forms a second liquid barrier that prevents saturation and pooling in the absorbent layer and enhances the OGR properties of the non-absorbent layer.

[0080] Typical oil and grease and aqueous barrier coatings often use specialty petroleum based polymer(s), wax, and/or higher polymer binder level compared to conventional print and binder coatings. Such coatings contaminate recycling streams by rendering otherwise recyclable materials are not recyclable because of problems with repulping coated paper material. Complex, sticky polymer coatings are difficult to breakdown in conventional acidic pulping process. When in a strongly acidic environment, for example, in a solution with a pH lower than 2, the coatings tend to clump and form “stickies”, and other particles are larger than the acceptable size for paper making from recycled materials.

[0081] Conventional coatings comprising petroleum based polymers similarity contaminate composting streams because they do not readily disintegrate in industrial scale composting processes. The high content specialty polymers, for example, petroleum based polymer binder makes it is extremely challenging for conventional coatings and coated paper materials to meet the >1% non-biodegradable compostion requirement for the ASTM D6868-11 compostability standard.

[0082] “Blocking” is another problem associated with paper materials coated with conventional coatings. Blocking occurs when layers of coated paper material stick together either in the real or after being rewound into rolls. More particularly, blocking in the reel is especially problematic when residual heat from the dryers dissipates slowly because of the large mass of the reel. Higher temperatures resulting from residual heat on the reel in turn can cause conventional coatings to stick or even melt as a result of thermal instability.

[0083] The lamination layer described herein improves upon conventional liquid barrier coatings because it is non-blocking, recyclable, and compostable. The lamination material is made out of non-biotoxic materials that are safe for food contact applications and meet the >99% biodegradable composition requirement of the ASTM D6868-11 standard. When placed between an absorbent crepe paper and a non absorbent OGR paper the lamination layer causes absorbed oils to wick across the surface of the absorbent layer. This wicking effect is produced by applying an impermeable, semi-permeable, or oleophilic lamination layer to an absorbent layer with an uneven surface. In one example, the absorbent layer is a crepe paper with ridges, valleys, and other small structures proliferating from—and protruding into—the paper's surface to help wick absorbed liquid into the main portion of the paper.

[0084] When applied to a surface of the non-absorbent layer, the lamination layer adheres to the structures proliferating from the surface of the absorbent crepe paper, thereby leaving gaps between ridges and other small structures on the surface of absorbent layer and the valleys protruding into the main portion of the paper. As liquids are absorbed by the absorbent layer, the liquid barrier formed by the lamination layer compresses the oils against the main portion of the absorbent layer and the lamination layer. This compression force drives the absorbed oil across the surface of the absorbent crepe in order to avoid pooling and seepage. By distributing oil more evenly across a greater portion of a food package, the composite material prevents absorbed oils from spoiling the reusability of food packaging while also making greasy foods healthier and less messy by removing fat, oil, grease, cholesterol, sodium, and other high calorie nutrients.

[0085] The lamination layer may further contain a binding agent that increases the lamination strength of the lamination layer. Increasing the layer's lamination strength causes the laminated surface of the non-absorbent layer to better adhere to the absorbent layer. In one example, applying the lamination layer to the absorbent layer and waiting a period of one to five seconds before joining the non-absorbent layer, improves the thermal degradation properties of the composite material. This method of combining the layers into a composite gives the lamination layer time to fill in the valleys on the surface of the absorbent layer, thereby creating a uniform surface to join the non-absorbent layer. Pressing the non-absorbent layer to a smooth surface of lamination layer fortifies the bond between the layers of the composite thereby increasing the flash point of the composite and minimizing paper curl. The lamination layer may also be applied as a print coating or can otherwise serve as a substrate for ink printing.

[0086] In an exemplary embodiment, the absorbent layer 12 is a crepe paper comprising cellulosic fibers and the non-absorbent layer 14 is an OGR paper. More specifically, in one embodiment the absorbent layer 12 is a crepe paper made of four to six layers of cellulose wadding having a basis weight of 12 to 18 pounds. The material may be virgin material that is biodegradable and recyclable. The sheets of wadding may be “pinned” together initially in an embossing type process to form a friction connection that creates a self-supporting sheet of absorbent material. An example of such absorbent material is the cellulose sheeting sold by Pregis Corporation under the trademark “Cushion Pack”.

[0087] As described, the absorbent layer 12 is backed by the non-absorbent layer 14 and optionally coated by a lamination layer. The non-absorbent layer 14 may be a OGR paper or polymeric film, such as polyethylene, that is glued, attached by a lamination film, or otherwise affixed to the absorbent layer to form the composite 10. In one embodiment, the non-absorbent layer is laminated 10 to provide additional oil and grease resistance.

[0088] The sustainable compost paper may also disintegrate naturally and be biodegradable, non-toxic, and compostable under American Society for Testing and Materials (ASTM) or Biodegradable Products Institute (BPI) standards, for example the ASTM D6400 testing criteria for plastic and the ASTM D6868 testing criteria for coated paper products.

[0089] In use, the composite 10 is placed against a pizza or other food item from which oil or grease is to be blotted with the absorbent layer 12 in contact with the food item. The composite 10 may contact either an upper or lower surface of the food, as desired, to extract oil or grease without adversely affecting the food. In the case of pizza, which is commonly placed in a box for transportation, this leads to at least the following two potential positions of the composite 10 relative to the box.

[0090] FIG. 3 illustrates a pizza box assembly 30 that includes a pizza box 20 and the pizza-blotting composite 10 shown in FIGS. 1 and 2. The pizza box 20 is a standard collapsible box used commonly in the industry, having an inner cavity or receptacle 22 for holding the pizza and a top 24 of the box 20, such that the absorbent layer 12 faces the inner receptacle 22. The composite 10 may be attached to the interior top 24 of the box 20 by any suitable means, including adhesives. In one aspect, the composite 10 may be removed after use and the pizza box 20 may be recycled.

[0091] FIG. 4 illustrates an alternative arrangement of the composite 10 relative to the pizza box, wherein the composite is located within the inner receptacle 22 of the pizza box at a location beneath the pizza. When the pizza in the box is cut or “scored” oil and grease from the pizza is efficiently wicked to the underside by the absorbent layer 12 without disturbing the upper surface of the pizza as can occur when its upper surface is blotted. Therefore, the arrangement of FIG. 4 operates advantageously in a surprisingly efficient manner to extract undesired oil and grease.

[0092] When the composite 10 is used beneath the pizza in the configuration of FIG. 4, the pizza may be cut prior to or after being placed on the composite. Due to the durable nature of the composite, it is not normally severed when a rolling cutter is used on the pizza.

[0093] Placement of the composite beneath the pizza enables excess oil and grease to pass downwardly to the composite for efficient absorption by the absorbent layer 12. The oil and grease cannot pass beneath the composite 10, however, because the non-absorbent layer 14 acts as a barrier. The bottom of the pizza box 20 therefore remains oil and grease-free, enabling it to be recycled.

[0094] As illustrated in FIG. 4, the composite 10 may be square or any other suitable shape to cover the bottom of the pizza box. Particularly when the composite is placed beneath a pizza or other food item, it may be desirable to cover the entire bottom of the container in which the food item is placed. Alternatively, the composite 10 placed beneath a pizza may be circular and dimensioned to match the outline of the pizza.

[0095] In other instances, such as when pizza or other food items are consumed on the premises of a restaurant, the composite can still be used under the food to absorb the oil and grease. In any case, once the pizza is finished, the composite may be folded inwardly onto itself without touching the grease-saturated absorbent layer 12 by grasping the non-absorbent layer 14.

[0096] When the composite 10 is used to blot a pizza or other food item from above, the non-absorbent layer 14 may have a flexible tab, string, or other physical feature 32 enabling the user to lift the composite away from the food without touching the saturated absorbent layer 12. The weight of the absorbed oil and grease then causes the composite 10 to hang downwardly with the grease-impermeable non-absorbent layer 14 on the outside, facilitating disposal of the composite without getting oil or grease on the user's hands.

[0097] When the non-absorbent layer 14 is metallic, the composite 10 also serves an additional purpose of retaining heat within the pizza by reflection in either an up or down direction, depending on the position of the composite.

[0098] In another form, separate pieces of the composite 10 may be provided above and below a pizza with the absorbent layer 12 facing and in contact with the surfaces of the pizza to absorb oil and grease from both the top and the bottom of the pizza. Alternatively, the top and bottom layers of the composite 10 may comprise a single sheet of the composite that extends underneath the pizza and is folded over to also engage the top of the pizza to absorb oil and grease from the top and bottom of the pizza simultaneously.

[0099] The foldable nature of the composite 10 enables it to be packaged in a compact and inexpensive package 40 which may be in the form of a sealed plastic, paper or foil-backed pouch, as illustrated in FIG. 5. In this form, the composite is suitable for distribution with a take-out pizza or other food item for convenient use by the consumer in extracting oil and grease from the food item. In situations where a composite 10 is provided above or below a pizza in the box of FIG. 3 or FIG. 4, another composite 10 might also be provided for manual use by the consumer to further reduce the quantity of oil and/or grease consumed.

[0100] FIG. 6 is a picture of a baking sheet 100 that was used to cook bacon at 450° F. As shown, the baking sheet 100 is fitted with a liner comprising the composite material 200. The dark colored areas 150 on the surface of the composite material 200 illustrate the oil and grease consumed by the material during and after cooking the bacon. The light colored areas 250 correspond to portions of the composite material that are not saturated with absorbed grease.

Characterization

[0101] Samples of the embodiments described herein were tested for compostability and absorbance. The chemical composition of the sample embodiments was also discerned to evaluate the material's safety for food contact applications. Compostability tests were performed according to the American Society for Testing and Material (ASTM) International test for standard specification for labeling of end items that incorporate plastics and polymers as coatings or additives with paper and other substrates designed to be aerobically composted in municipal or industrial facilities or the ASTM 6868. Tests were performed under laboratory conditions at the University of Wisconsin-Stevens Point Institute for Sustainable Technology in Stevens Point, Wis.

[0102] The ASTM 6868 is a set of testing criteria used by the Biodegradable Products Institute (BPI) to certify compostable materials and products such as food packaging. BPI relies on the ASTM D6400 test for plastic and the ASTM 6868 test for coated paper products or paper materials polymer binding agents. To pass ASTM tests and become part of BPI's certified compostable program, a product must: i) disintegrate quickly leaving no visible residue that has to be screened out, ii) biodegrade fully or convert rapidly to carbon dioxide water and biomass, iii) result in compost that supports plant growth, and iv) not introduce high levels of regulated materials into the soil.

[0103] The ability of samples to absorb fat, calories, cholesterol, fatty acids, and sodium from the surface of cooked take-out pizzas was tested using pizzas obtained from PIZZA HUT, DOMINO's, PAPA JOHN's, LITTLE CAESARS, and SABARRO. Pizzas contacting samples included thin crust pizzas, thick crust pizzas, meat lovers pizzas, and veggie pizzas. Testing was performed under laboratory conditions by COVANCE LABORATORIES, INC. of Madison, Wis.

Compostability

[0104] Disintegration and biodegradation methodology for this experiment was based on a modified version of the ASTM method for compostability tested without humidified aeration and carbon dioxide capture (ASTM D5338). Industrial composition conditions were simulated in a laboratory incubator set to 58° C.±2° for 7 weeks in the Wisconsin Institute for Sustainable Technology Compostability Laboratory at the University of Wisconsin Stevens Point College of Natural Resources. The composting vessels were 2-liter KIMAX glass bottles closed at the top by a rubber stopper fitted with a hole running through the center. An air-tight rubber sleeve was fitted around the threaded mouth of the bottles to avoid sticky glass on rubber contacts between the bottle and stopper. A plastic tube was inserted through the stopper hole into the glass bottle to limit moisture loss while providing for controlled gas exchange during composting.

[0105] There were two treatments tested in this example: a paper composite material and untreated cellulose paper. A negative blank of mature compost was also tested as a control. The untreated cellulose paper and paper composite material were added to compost in a 6:1 or 16% paper to dry compost ratio. Each treatment and the control were replicated seven times with each vessel comprising a complete, distinct sampling unit. There were twenty one vessels at the beginning of the experiment, with three sampling units removed at the end of weeks 1,2,3,4,5,6, and 7. The vessels were placed in the incubator in a complete randomized design.

[0106] The compost in this experience is municipal, deciduous left compost (mature 2-4 months) sourced from Hsu's Compost and Soils in Wausau, Wis. Hsu's leaf compost is certified through the United States Composting Council (USCC) according to the Seal of Testing Assurance (STA) program. The compost was composed of tree leaves from municipal collection in the Wausau and Appleton, Wis. areas. Each 2-liter vessel required 615 g of as-received (moist) compost. The compost was sieved using an 8 mm sieve to remove large debris, which was then discarded. Mature compost was used based upon the D5338 method for coated paper disintegration.

[0107] The paper composite material was prepared using an absorbent crepe paper and a non-perfluorooctanoic acid (PFOA), non-perfluorooctane sulfuric acid (PFOO), non-perfluorinated carboxylic acid (PFCA), and non-perchlorate OGR paper from Expera Specialty Solutions in Moisinee, Wis. The papers laminated together using a non-hazardous water based polymer emulsion laminate supplied from—and applied by—Prolamina Flexible Packaging Solutions, a division of Proampac, in Neenah, Wis. The untreated cellulose paper was also obtained from Expera Specialty Solutions.

[0108] The paper treatments were incoproated into the compost by cutting the paper and paper composite material, by hand, into 2 cm×2 cm squares according to the ASTM D5338. The squares were then weighted in a beaker to discern the number of squares added to each vessel to achieve the desired 6:1 (615 g:98.4 g) compost to paper ratio. Compost (615 g) was weighed into each of the twenty one vessels and the pre-weighted paper was added. Distilled water was added to bring the entire compost and paper matrix up to 60%±2% moisture content. Between 101 mL and 110 mL of distilled water was added to each vessel and moisture content of the initial compost was determined gravimetrically by weighing samples from each vessel and drying for 48 hours in a 105° C. oven. The compost, paper, and water were mixed thoroughly using 2-pronged forks until a uniform matrix was produced. Each vessel was labeled with the week of its removal, the treatment, and the paper addition.

[0109] Each week during the 7 week active composting period, the compost vessels were removed from the incubator and weighed. Moisture was maintained between 50% and 60% throught the 7 week trial. Moisture additions were based on individal jar weight loss and visual observations of compost and paper structure. Moisture additions were made by adding distilled water to individual vessels based on weight and additional water was mixed in using a flat soil knife. Hand mixing was necessary to promote aeration and consistent moisture distribution throughout the compost matrix. Mixing occurred twice a week, once with moisture additions and once without.

[0110] During final sampling of vessels removed at various weeks, the paper was separated from the compost using a series of 3 brass sieves (8 mm, 4 mm, and 2 mm) and picked from the compost using tweezers. Paper too large to pass throughout the 2 mm sieve was weighted (including residual compost). Paper was further processed by washing with de-ionized water over a 2 mm sieve. With much of the residual compost removed, the paper was dried in an oven at 60° C. for 6 hours. Final paper mass was recorded once dry. Paper and compost, per vessel, from removed vessels, were stored separately in quart sized ZIPLOC freezer bags. The remaining vessels were returned to the incubator in a re-randomized order. Samples from removed vessels were frozen and stored in a 0° C. walk-in freezer.

[0111] Results of the compostability testing are shown below in Table 1.

TABLE-US-00001 TABLE 1 % Breakdown Material Start Weight Final Weight Theoretical Carbon Composite Material 98.4 g 19.1 g 80.6 Untreated Cellulose 98.4 g 19.9 g 79.8 Paper

[0112] After 5 weeks, the composite paper material and the untreated cellulose paper were both ahead of the 90% breakdown benchmark (72% breakdown). After 12 weeks, the % breakdown theoretical carbon of the composite material was over the ASTM D6868 90% benchmark for biodegradation and more than 90% of the original materilal was lost to disinigration.

[0113] FIG. 6 illustrates the % breakdown of the composite material and the untreated cellulose paper over the first 5 weeks of the compostability testing. As shown in the figure, after 10 days, the composite material was in-line with or exceeded the 90% breakdown benchmark. Furthermore, after 35 days, the composite material out performed both the 90% benchmark (by 8.6%) and the untreated cellulose paper (0.8%) in biodegradation and disinegration.

Nutrient Absorbance

[0114] The composite material was evaluated for its ability to absorb excess nutrients from the surface of greasy take out foods. Pads made from the composite material were placed in contact with pizzas obtained from five popular take out pizza chains—PIZZA HUT, DOMINO's, PAPA JOHN's, LITTLE CAESARS, and SABARRO in Madison, Wis. Pads weight ranged from 11.8 g to 7.3 g so that pads of various sizes could be evaluated for there ability to absorb nutrients from different types of take out pizza. Thin crust, thick crust, “meat lovers”, and veggie type pizzas were tested. Absorbance experiments were performed by Covance Laboratories, Inc. of Madison, Wis. Samples very prepared in the field in a mobile laboratory and nutrient extraction was performed under laboratory conditions using the Soxhlet extraction method.

[0115] Samples were prepared by applying pads to the top and bottom surfaces of the pizzas. Once in contact with the pizza, the composite material absorbed nutrients from the pizza surface into the pads. Soaked pads were stored on ice and transported to Covance Laboratories for nutrient extraction and absorbance analysis.

[0116] Nutrients were absorbed form the pizzas using this method: i) weigh composite paper material pad before use, ii) obtain a take out pizza in corrugated cardboard pizza box from a take out restaurant, iii) within 5 minutes of purchasing the pizza, insert the pad underneath the bottom surface of the pizza so that the pad is between the pizza surface and the cardboard box, iv) close the pizza box and weight 30 minutes, v) apply a second pad to the top surface of the pizza by pressing down lightly to assure contact between the pizza and the composite material, vi) remove both pads after 2 minutes of contact by the second pad, vii) remove any loose toppings of pizza material from the pads, and viii) weigh each pad separately immediately after use.

[0117] Nutrients were extracted from prepared samples using the Soxhlet extraction method. The extraction was conducted under laboratory conditions using the extraction method described in Official Methods of Analysis of AOAC INTERNATIONAL, Method 960.39 and 948.22 published by AOAC INTERNATIONAL of Gathersburg, Md. Excess nutrients were extracted from pads made from paper composite material by: i) obtain pads applied to take food in the field, ii) weigh pads into a cellulose thimble containing sea sand and dried to remove excess moisture, iii) extract nutrients from pads using pentene as a solvent for 5 hours, iv) evaporate pentene from the extract, v) dry and weigh the extract for analysis.

[0118] Upon extraction, the composition of extracted nutrients was determined by Inductively coupled plasma atomic emission spectroscopy (ICP-AES). This technique produces an inductively coupled plasma to excite atoms into emitting a electromagnetic radiation response that is characteristic of a particular element or combination of elements. Measured sodium and fat content of the extract absorbed by the composite paper material pads was then used to calculate the fat and sodium content of the nutrients absorbed by the pad from the pizzas. The percent of the pizza's total sodium and fat content absorbed by the composite material was determined using the nutrient content analysis to provide an estimate for the paper composite materials ability to remove fat and sodium from take out foods.

[0119] Results of the fat absorance analysis including are displayed below in Table 2.

TABLE-US-00002 TABLE 2 Absorbed Absorbed % Fat Sample Nutrients Absorbed Fat Calories Reduction Pad 1 11.80 g  10.49 g  94.4 Cal 9.5% Pad 2 9.60 g 9.09 g 81.8 Cal 8.8% Pad 3 9.10 g 8.12 g 73.1 Cal 7.4% Pad 4 10.60 g  7.97 g 71.8 Cal 6.1% Pad 5 11.10 g  9.42 g 84.8 Cal 8.1% Pad 6 8.60 g 6.88 g 61.9 Cal 5.6% Pad 7 8.60 g 6.48 g 58.3 Cal 5.0% Pad 8 9.60 g 8.70 g 78.3 Cal 8.0% Pad 9 7.30 g 6.77 g 60.9 Cal 6.4% Pad 10 8.90 g 8.29 g 74.6 Cal 7.9% Average 9.52 g 8.22 g 69.2 Cal 7.3%

[0120] Fat in this analysis includes saturated fatty acids, monounsaturated fatty acids, poloyunsaturated fatty acids, and trans fatty acids. The fatty acids measured in this analysis include, Butyric Acid, Caproic Acid, Caprylic Acid, Capic Acid, Lauric Acid, Myristic Acid, Myristoleic Acid, Pentadecanoic Acid, Pentadecenoic Acid, Palmitic Acid, Heptadecanoic Acid, Heptadecenoic Acid, Stearic Acid, Oleic Acid, Linoleic Acid, Arachidic Acid, Gamma Linolenic Acid, Elcosadienoic Acid, Behenic Acid, Erucic Acid, Elcosatrienoic Acid, Arachidonic Acid, Arachidonic Acid, and Lignoceric Acid. On average, 86.5% of all Absorbed Nutrients were Fat leaving only 13.5% for sodium, cholestoal, an other nutrients. % Total Fat was calculated assuming a pizza with 98 g fat per serving.

[0121] Results of the sodium absorbance analysis are shown below in Table 3.

TABLE-US-00003 TABLE 3 Absorbed Absorbed % Sodium % Daily Sample Nutrients % Sodium Sodium Reduction Value Pad 11 10.2 g 0.56% 57.6 mg  1.0%  1.6% Pad 12 15.6 g 0.10% 15.3 mg 0.27% 0.64% Pad 13 34.6 g 0.07% 25.5 mg 0.45% 1.06% Average 21.0 g 0.24% 32.8 mg 0.57%  1.1%

[0122] Sodium measured in this analysis includes chloride and sodium chloride salt. % Sodium Reduction was based on a total sodium value of 5,610 mg per serving and % Daily Value was calculated using a 3,400 mg sodium daily value.

Thermal Insulation

[0123] The composite material was evaluated for its ability to thermally insulate food. Specifically, the material's tendency to reduce heat loss from cooked food while inside conventional food packaging was evaluated relative to a control sample. Temperature data was gathered on large pizzas obtained from five popular take out pizza chains—PIZZA HUT, DOMINO's, PAPA JOHN'S, LITTLE CAESARS, and SABARRO in Madison, Wis. In order to isolate the thermal insulation character of the composite material, pizzas were kept in corrugated cardboard boxes throughout the experiment for both the control samples and the samples containing the composite material. Thermal insulation experiments were performed by COVANCE LABORATORIES, INC. of Madison, Wis. Samples were prepared and temperature data was collected in the field in a mobile laboratory using an infrared thermometer.

[0124] Samples containing the composite material were prepared by placing a first pad composed of the composite paper material under the pizza and a second pad over the top surface of the pizza 10 minutes after obtaining the pizza. Temperature measurements were made for the control samples 5 minutes after receiving the pizza and 30 minutes after receiving the pizza. The total time for the control experiment was 25 minutes. For the composite material samples, temperature measurements were made 5 minutes after obtaining the pizza (5 minutes before placing the sheet) and 30 minutes after applying the pads to the pizza. The total time for the composite material experiment was 35 minutes. To obtain the thermal insulation property, the initial temperature of the pizza was subtracted from the final temperature of the pizza. Each experiment was repeated seven times to collect data across multiple trials.

[0125] Results of the thermal insulation experiments for the control samples are displayed below in Table 4.

TABLE-US-00004 TABLE 4 Sample Initial Temperature Final Temperature Temp. Difference Control 1 58.9° C. 47.9° C. 11.0° C. Control 2 69.0° C. 58.8° C. 10.2° C. Control 3 69.9° C. 61.7° C.  8.2° C. Control 4 75.6° C. 63.2° C. 12.4° C. Control 5 69.3° C. 59.2° C. 10.1° C. Control 6 70.4° C. 54.2° C. 16.2° C. Control 7 69.5° C. 46.2° C. 23.3° C. Average 68.9° C. 55.9° C. 13.1° C.

[0126] Results of the thermal insulation experiment for the composite material samples are displayed below in Table 5

TABLE-US-00005 TABLE 5 Sample Initial Temperature Final Temperature Temp. Difference Pad 1 61.6° C. 54.4° C.  7.2° C. Pad 2 59.0° C. 54.4° C.  4.6° C. Pad 3 66.1° C. 59.5° C.  6.6° C. Pad 4 64.4° C. 53.1° C. 11.3° C. Pad 5 67.2° C. 53.8° C. 13.4° C. Pad 6 66.1° C. 54.4° C. 11.7° C. Pad 7 66.4° C. 47.3° C. 19.1° C. Average 64.4° C. 53.8° C. 10.6° C.

[0127] The preceding discussion merely illustrates the principles of the present pizza-blotting composites and pizza box assemblies containing such pizza-blotting composites. It will thus be appreciated that those skilled in the art may be able to devise various arrangements, which, although not explicitly described or shown herein, embody the principles of the inventions and are included within their spirit and scope. Furthermore, all examples and conditional language recited herein are principally and expressly intended to be for educational purposes and to aid the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions.

[0128] Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. Terms such as “upper”, “top”, and “lower” are intended only to aid in the reader's understanding of the drawings and are not to be construed as limiting the invention being described to any particular orientation or configuration.

[0129] This description of the exemplary embodiments is intended to be read in connection with the figures of the accompanying drawings, which are to be considered part of the entire description of the invention. The foregoing description provides a teaching of the subject matter of the appended claims, including the best mode known at the time of filing, but is in no way intended to preclude foreseeable variations contemplated by those of skill in the art.