Zein coated or impregnated paper straws and related tublar article

Abstract

The present invention comprises a method, process, and composition that enhances the performance of paper straws through the use of zein treatments which significantly enhance the wet strength of paper straws. Selection of the paper substrate found that Hanji paper displays remarkable durability, reinforcing performance of the straws even when exposed to water and high salinity. Furthermore, the present invention exhibits substantial effectiveness in curbing starch migration from the paper straws, creating a protective barrier against starch-based glues that might otherwise compromise beverage flavor and pose gluten-related concerns. Additionally, the present invention outlines a method for crafting spirally-wound straws using a biodegradable paper strip impregnated with the zein treatment. The straws of the present invention offer an adhesive-free, sustainable, and environmentally-friendly solution for making durable straws.

What is claimed is: 
     
         1 . A tubular article comprising a biodegradable and compostable substrate, which is coated with, impregnated with, or both coated and impregnated with, a biodegradable and compostable zein or mixtures of zein. 
     
     
         2 . The article of  claim 1 , wherein the zein includes a (alpha), R (beta), or both a (alpha) and R (beta) zein classes. 
     
     
         3 . The article of  claim 1 , wherein the substrate is paper, Hanji paper, Washi paper, Xuan paper, Kozo paper, or papers obtained from natural biomaterials, and the paper has a weight range of approximately 0.1-2000 gsm (gram per square meter). 
     
     
         4 . The article of  claim 3 , wherein the article formed from the substrate is a biodegradable and compostable zein coated paper straw. 
     
     
         5 . The article of  claim 1  wherein the article has at least one of following characteristics: enhanced mechanical properties; enhanced wet strength properties; restricted starch migration; increased salinity resistance; free of adhesive, starch, gluten and reduced and/or effectively eliminated PFAS compounds; improved performance, durability, and superior mechanical resilience; maintains firmness over time; or exhibits enhanced resistance to saltwater exposure. 
     
     
         6 . The article of  claim 1 , wherein as additional components in the zein component are plasticizers, inorganic colloidal particles, active agents, inorganic colloidal particles, spherical particles, carrier particles, food colorant, flavor agent, or combinations thereof. 
     
     
         7 . The article of  claim 1 , wherein the zein coated article has the following weight percentages of components based on the total article weight:
 (ii) 0.01-99 wt. % of a biodegradable and compostable mixture of zein;   (ii) 0.01-10 wt. % of water;   (iii) 0.00-15 wt. % of a plasticizer;   (iv) 0.00-5 wt. % of inorganic colloidal particles;   (v) 0.00-80 wt. % of an active agent;   (vi) 0.00-95 wt. % of spherical particles, optionally encapsulated; and   (vii) 0.01-5 wt. % of natural fibers; and   
       wherein the sum of the percentages of (i) to (vii) equals 100 percent. 
     
     
         8 . The article of  claim 1  wherein the article is a biodegradable and compostable zein coated article selected from a straw or tubular device having:
 i. controlled release properties from actives contained in the zein coating or within the tube space, optionally encapsulated; 
 j. coated spherical particles present in the interior of the tube; 
 k. coated disposable food-service items selected from tablecloths, napkins, or plates; 
 l. straws that are delivery devices for nicotine, caffeine or cannabinoids; 
 m. tubes as pest control tubes filled with actives or spheres coated with actives for targeted eradication; 
 n. tubes having spheres in their interior designed for controlled delivery of fertilizers in home gardening and agricultural applications; 
 o. tubes to deliver oral care products, toothpicks, or floss; 
 p. tubes as packaging materials for consumer use; or 
 q. tubes for industrial container and package applications. 
 
     
     
         9 . A process for preparing a zein coated article, comprising:
 (a) Preparing a zein powder containing zein polymer (10-99.9% by wt.), water (0.1-10% by wt.), and starch particles (0.01-80% by wt.), wherein all percentages are based on the total weight of the zein powder;   (b) Using the zein powder from step (a) in one or more of the following steps:
 (i) Grinding the zein powder with inorganic colloidal particles and sieving; 
 (ii) Preparing a zein solution by mixing the zein powder with a solvent or plasticizer or both; 
 (iii) Separating insoluble starch particles and contaminants using decantation or filtration; 
 (iv) Performing adsorptive filtration to remove color or odor; 
 (v) Adding soluble or insoluble active agents and/or crosslinking agents; and 
 (vi) Homogenizing and aging the solution at a temperature between 30-80° C. for 0.1 hour to 48 hours; 
   (c) Coating a pre-manufactured paper straw with the zein solution to create a zein-coated paper straw; or creating straws by spirally winding zein pre-impregnated paper strips;   (e) Drying the zein-coated paper straw at a temperature between 20-200° C. for a duration of about 1-180 minutes; and   (f) Cutting the zein-coated paper straw to a desired length as needed.   
     
     
         10 . The process of  claim 9  further comprising one or more of the following steps:
 (a) Packing the zein-coated paper straw with biodegradable, compostable, and/or environmentally inert spherical particles laden with active agent compositions and incorporating porous fiber layers; 
 (b) disinfecting and sterilizing the zein-coated paper straw using UV light, ozone, or non-thermal plasma; and 
 (c) Individually wrapping or packaging the zein-coated paper straw. 
 
     
     
         11 . The process for manufacturing an article of  claim 9 , including spirally winding a previously pre-impregnated paper strips around a core. 
     
     
         12 . The process for manufacturing an article of  claim 9 , using a paper selected from Hanji, Washi, or Xuan Paper. 
     
     
         13 . The process of  claim 11  wherein the paper is Hanji having a weight of approximately 0.1-2000 gsm. 
     
     
         14 . A method of using a zein coated article of  claim 1 , wherein the coated article has a zein film or particle having an active agent present either in the zein film or interior of the tubular article or both for application of the active agent to the desired site. 
     
     
         15 . The method of  claim 14 , wherein the zein coated article is a paper straw that is packed with spherical particles, wherein these particles are a carrier for active agents for use by a person for sipping from the straw. 
     
     
         16 . The method of  claim 14  wherein the zein coated tubular article contains, in either the zein coating on the tubular article or in the interior of the tubular article or both, one or more of a bioactive agent; medicinally active agent; hygienically active agent; cosmetically active agent; stimulating agents selected from the group consisting of nicotine and its salts, caffeine, and cannabinoids; essential oil; flavoring agent; sweetening agent; and pest control agents; or a combination thereof. 
     
     
         17 . The method of  claim 14 , wherein the particles have one or more spherical particles or beads, selected from glass beads, porous glass beads, hollow glass beads, granular activated carbons, spherical activated carbons, ion exchange polymers, spherical micro calcium carbonate particles, crosslinked biodegradable hydrogels, or spherical cellulose particles. 
     
     
         18 . The method of  claim 14 , wherein the spherical particles incorporate porous fiber stuffing within a zein coated paper straw to aid in retaining the particles within the straw. 
     
     
         19 . The method of  claim 14 , wherein a zein article paper straw is packed with encapsulated, active agent-loaded spherical particles, and enables water to be sipped by a person through the straw which releases the active agents to the person. 
     
     
         20 . The method of  claim 14 , additionally encompassing the actions of sipping, gargling, and spitting out active-loaded water or other liquids contained or delivered by use of the zein straw to an individual for the purpose of oral care. 
     
     
         21 . The method of  claim 14 , for the treatment of insect pests comprising the use of paper tubular articles, wherein both the tubular paper material itself and the carrier particles loaded with actives, can be carried away by pest insects for their targeted eradication. 
     
     
         22 . The method of  claim 14 , including the use of the paper tabular articles as a fertilizer tube placed in the soil, wherein the carrier particles loaded with actives serve as a means to release plant nutrition agents and antifungal and/or other known protective agents to the plant. 
     
     
         23 . A biodegradable and compostable zein coated article of  claim 1  comprising the articles' use as:
 a. Disposable food-service items, including paper straws, coffee stirrers, cups, plates, forks, knives, chopsticks, tablecloths, napkins, food picks, and food containers for fries, nuggets, and burgers; 
 b. Smoke-free tobacco and nicotine delivery paper straws; 
 c. Delivery paper straws for caffeine and cannabinoids; 
 d. Pest control devices for targeted eradication; 
 e. PFAS reduction tubular device; 
 f. Tubes designed for controlled delivery of fertilizers in home gardening and agricultural applications; 
 g. Oral care products; and 
 h. Packaging materials for both consumer and industrial purposes.