Recyclable and compostable eating utensils and other products made from crop-based resin & method of manufacture

This application is a continuation of International Patent Application No. PCT/US2006/046994, filed Dec. 11, 2006, which claims the benefit under 35 USC 119(e) of U.S. Provisional Patent Application No. 60/749,441, entitled “RECYCLABLE AND COMPOSTABLE EATING UTENSILS AND OTHER PRODUCTS MADE FROM CROP-BASED RESIN & METHOD OF MANUFACTURE,” filed Dec. 12, 2005, and U.S. Provisional Patent Application No. 60/846,059, entitled “RECYCLABLE AND COMPOSTABLE EATING UTENSILS AND OTHER PRODUCTS MADE FROM CROP-BASED RESIN & METHOD OF MANUFACTURE,” filed Sep. 20, 2006. All of these related applications are incorporated herein by reference and made a part of this application. If any conflict arises between the disclosure of the invention in this continuation application and that in the related provisional applications, the disclosure in this continuation application shall govern. Moreover, the inventors incorporate herein by reference any and all U.S. patents, U.S. patent applications, and other documents, hard copy or electronic, cited or referred to in this application.

The words “comprising,” “having,” “containing,” and “including,” and other forms thereof, are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items, or meant to be limited to only the listed item or items.

“triangular” shall mean shaped somewhat like a triangle.

“pentagonal” shall mean shaped somewhat like a pentagon.

“hexagonal” shall mean shaped somewhat like a hexagon.

“rectangular” includes square.

“substantially clean room conditions” shall mean under sanitary conditions, but not necessarily sterile conditions.

It is highly desirable to make products that may be recycled and turned into compost for fertilizer in either commercial or non-commercial composting facility. Most government certified commercial composting facilities have the ability to convert biodegradable material having a thickness of about 19 millimeters or less into compost within less than about 90 days. Petroleum based plastic products ordinarily are not biodegradable and cannot be converted into compost.

Products made from resins that are biodegradable frequently cannot withstand elevated temperatures and lose their rigidity. This is an acute problem in attempting to make rigid products such as eating utensils that can withstand the elevated temperatures encountered during shipping or use under certain conditions. Eating utensils such as chopsticks typically use wood for their superior heat-resistance and rigidity. The destruction of forests, some 40 million trees per year, require new innovation. In order to avoid the destruction of the vast number of trees currently used to make wooden chopsticks, it would be highly desirable to make chopsticks from a moldable resin comprising an annually renewable agricultural resource. In making chopsticks, the wood is typically cut into an elongated segment with a rectangular cross-sectional configuration.

This invention has one or more features as discussed subsequently herein. After reading the following section entitled “DETAILED DESCRIPTION OF SOME EMBODIMENTS OF THIS INVENTION,” one will understand how the features of this invention provide its benefits. These benefits include, but are not limited to: (a) the product\'s ability to withstand elevated temperatures without deforming and losing rigidity, (b) the product\'s ability to be virtually non-heat conducting so it acts as an insulator, (c) the product\'s strength and impact resistance so it won\'t shatter when struck or dropped, (d) the product\'s non-toxicity so it may be used as an eating utensil, (e) the eating utensil product\'s water and heat resistance so it is dishwasher safe, (f) the product\'s ability to be recycled, and (g) the product\'s ability to be converted into environmentally-safe compost.

Without limiting the scope of this invention as expressed by the claims that follow, some, but not necessarily all, of its features are:

One, this invention is a recyclable, biodegradable, rigid product formed from a crop-based resin. The crop-based resin may be derived from wheat and it may be heat treated to control its moisture content so that it contains substantially from 0 to 3 weight percent water when used to form the product of this invention. It may also be substantially entirely a carbohydrate polymer, but it may include synthetic constituents. Crop-based resins may also include resins produced by microorganism fed on vegetable matter, even grass or other cellulose material. Suitable crop-based resins that may be used to form the products of this invention are disclosed in U.S. Pat. Nos. 5,321,064 and 5,446,078.

Two, the recyclable, biodegradable, rigid products of this invention are sized so that an individual product\'s maximum thickness dimension is 19 millimeters. A host of products may thus come within the scope of this invention, including but not limited to, eating utensils such as, for example, chopsticks, knives, forks, spoons, sporks, coasters, stirring devices for hot drinks, insulating sleeves for cups, etc. One product of this invention is an eating utensil that meets ASTM D6400-04 published standard. The eating utensil may be fully colorized by incorporating a non-toxic dye therein during its formation. It may be marked during its formation with an advertisement. It may be dishwasher-safe and may be capable of being reused and washed repeatedly.

Three, the products of this invention decompose into a compost within 120 days or less. Consequently, the products of this invention may be buried in a landfill with naturally occurring microorganisms present so the microorganisms convert the products into compose within 120 days or less. The products of this invention may also be decomposed in a certified commercial composting facility within at least 90 days to produce an environmentally-safe compost.

Four, the products of this invention are heat resistant being able to remain in hot water at a temperature of at least 190 degrees Fahrenheit for at least 15 minutes without any substantial loss in rigidity.

Five, the products of this invention, in particular the eating utensils, may be contained within a sealed package of a thin film comprising a crop-based resin that decomposes into a compost within 120 days or less.

These features are not listed in any rank order nor is this list intended to be exhaustive.