Methods and compositions for on-demand release of ClO2 gas from UV-activated chlorite ion

Patent metadata

Field	Value
Publication number	US-11590472-B2
Application number	US-201615753312-A
Country	US
Kind code	B2
Filing date	Aug 18, 2016
Priority date	Aug 18, 2015
Publication date	Feb 28, 2023
Grant date	Feb 28, 2023

Abstract

Compositions and methods for generating ClO 2 gas are disclosed. A composition that includes a chlorite salt is activated by exposure to ultraviolet light. After an optional storage period, the composition is then exposed to moisture, resulting in the generation of ClO 2 gas. Exemplary compositions include polymers in which the chlorite salt is dispersed. The polymers may be used to form films that can be used to package, e.g., food products, pharmaceutical products, medical devices, and/or laboratory devices. Upon exposure to ultraviolet light and moisture, the packaging releases controlled quantities of ClO 2 gas, which may disinfect and/or deodorize the packaged device or product.

First claim

We claim:

1. A method for generating chlorine dioxide from a composition comprising a polymer and a plurality of chlorite ions disposed in the polymer, the method comprising:
exposing the composition to ultraviolet (UV) light; and
exposing the composition to moisture, wherein exposing the composition to moisture comprises exposing the composition to humidified gas having a relative humidity within the range of 60% to 100%,
wherein the composition does not generate a significant amount of chlorine dioxide when exposed to the UV light alone and does not generate a significant amount of chlorine dioxide when exposed to the humidified gas alone.

2. A method according to claim 1 , wherein exposing the composition to ultraviolet light comprises exposing the composition to UV light having a wavelength in the range of about 240 nm to 280 nm.

3. A method according to claim 1 , wherein the composition comprises less than 10% by weight of an energy-activated catalyst and comprises 2% or less by weight of an acid-releasing agent.

4. A method according to claim 1 , wherein the composition comprises less than 5% by weight of an energy-activated catalyst and comprises 1% or less by weight of an acid-releasing agent.

5. A method according to claim 1 , wherein the composition comprises less than 2% by weight of an energy-activated catalyst and comprises 1% or less by weight of an acid-releasing agent.

6. A method according to claim 1 , wherein the plurality of chlorite ions are present in the composition in the form of a chlorite salt.

7. A method according to claim 6 , wherein the chlorite salt is sodium chlorite or potassium chlorite.

8. A method according to claim 6 , wherein the composition comprises a weight ratio of an energy-activated catalyst to chlorite salt of 1:5 or less and comprises a weight ratio of an acid-releasing compound to chlorite salt of 1:10 or less.

9. A method according to claim 6 , wherein the composition comprises a weight ratio of an energy-activated catalyst to chlorite salt of 1:10 or less and comprises a weight ratio of an acid-releasing compound to chlorite salt of 1:50 or less.

10. A method according to claim 1 , wherein the step of exposing the composition to UV light and the step of exposing the composition to moisture are performed simultaneously.

11. A method according to claim 1 , wherein the step of exposing the composition to UV light is performed prior to the step of exposing the composition to moisture.

12. A method according to claim 11 , wherein the step of exposing the composition to UV light and the step of exposing the composition to moisture are separated by an intervening period of time, wherein the intervening period of time is at least one minute.

13. A method according to claim 1 , further comprising drying the composition so that the composition has the moisture content of less than 500 ppm.

14. A method according to claim 13 , wherein the drying occurs prior to the step of exposing the composition to UV light.

15. The method of claim 1 , wherein the amount of chlorine dioxide generated from the composition upon exposure to moisture alone or UV light alone is at least 20 times less than when the composition is exposed to both UV light and moisture.

16. The method of claim 1 , wherein the amount of chlorine dioxide generated from the composition upon exposure to moisture alone or UV light alone is at least 50 times less than when the composition is exposed to both UV light and moisture.

17. The method of claim 1 , wherein the amount of chlorine dioxide generated from the composition upon exposure to moisture alone or UV light alone is at least 100 times less than when the composition is exposed to both UV light and moisture.

Assignees

• Wisconsin Alumni Res Found
• Bemis Co Inc

Inventors

• Abbott Nicholas
• Jain Rishabh
• Nelson Kevin
• Busche David
• Lynn David

Classifications

• B32B27/304

  comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF · CPC title

• B32B27/00

  Layered products comprising {a layer of} synthetic resin {(fibrous or filamentary layer made of a synthetic resin B32B5/02; particulate layer made of a synthetic resin B32B5/16; foamed layer made of a synthetic resin B32B5/18)} · CPC title

• B32B27/32 Primary

  comprising polyolefins {(comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30)} · CPC title

• B32B2264/10

  Inorganic particles · CPC title

• B65D1/00

  Rigid or semi-rigid containers having bodies formed in one piece, e.g. by casting metallic material, by moulding plastics, by blowing vitreous material, by throwing ceramic material, by moulding pulped fibrous material or by deep-drawing operations performed on sheet material (with curved or partially-curved cross-section made by winding or bending paper B65D3/00; with polygonal cross-section formed by folding B65D5/00; specially constructed to be opened by cutting, piercing or tearing of wall portions B65D17/00; rigid pallets with side walls B65D19/02) · CPC title