Ozone adhesion process for insulating container manufacture
View Patent ↗Systems and methods for improving adhesion of an insulating foam to a molded polymeric insulating structure through use of ozone gas for functionalization of molded polymeric surfaces of an internal cavity of the insulating structure.
1. A method of manufacturing an insulating container, comprising:
molding an external structure of the insulating container from a polymer, the external structure comprising:
an inner trough;
an outer shell coupled to the inner trough by a top edge surface;
an internal cavity spaced between the inner trough and the outer shell and extending around four sides and a base of the external structure;
a first opening extending into the internal cavity at a first corner of a base surface of the outer shell;
a second opening extending into the internal cavity at a second corner, opposite the first corner, of the base surface of the outer shell;
positioning the external structure such that the second opening is above the first opening;
injecting an ozone gas containing 5-7.5% ozone into the first opening;
filling at least 80% of the cavity with the ozone gas to displace a mass of air out through the second opening;
flushing the cavity with air to remove ozone gas from the cavity; and
filling the cavity with an insulating foam.
2. The method of claim 1 , wherein a volume flow rate of the ozone gas into the first opening is such that a volume of the cavity is filled in at least 4 minutes.
3. The method of claim 1 , wherein a volume flow rate of the ozone gas into the first opening is such that a volume of the cavity is filled in at most 10 minutes.
4. The method of claim 1 , wherein the flushing the cavity with air further comprises flushing for at least 2 minutes.
5. The method of claim 1 , wherein the flushing the cavity with air to remove ozone gas comprises removing at least 95% of the ozone gas from the cavity.
6. The method of claim 1 , wherein the flushing the cavity with air to remove ozone gas comprises removing at least 97% of the ozone gas from the cavity.
7. The method of claim 1 , wherein the flushing the cavity with air to remove ozone gas comprises removing at least 99% of the ozone gas from the cavity.
8. The method of claim 1 , wherein the molding of the external structure utilizes a rotational molding process.
9. The method of claim 1 , wherein the polymer is polyethylene.
10. The method of claim 1 , wherein the insulating foam is polyurethane.
11. The method of claim 1 , wherein the ozone gas is injected at room temperature.
12. The method of claim 1 , wherein the outer shell has a substantially cuboidal shape.
13. A method for producing an insulating structure, comprising:
(a) molding an outer shell of the insulating structure from a polymer, the outer shell comprising:
an internal cavity;
a first opening extending into the internal cavity;
a second opening extending into the internal cavity;
(b) positioning the outer shell such that the second opening is above the first opening;
(c) injecting an ozone gas containing 5-7.5% ozone into the first opening;
(d) filling the cavity with the ozone gas to displace a mass of air out through the second opening;
(e) at a time after step (d), filling the cavity with a gas to remove at least 97% of the ozone gas from the cavity; and
(f) injecting an insulating foam into the cavity.
14. The method of claim 13 , wherein a volume flow rate of the ozone gas into the first opening is such that a volume of the cavity is filled in at least 4 minutes.
15. The method of claim 13 , wherein a volume flow rate of the ozone gas into the first opening is such that a volume of the cavity is filled in approximately 4-10 minutes.
16. The method of claim 13 , wherein step (e) begins approximately 4 to 10 minutes after step (c) began.
17. The method of claim 13 , wherein step (e) is completed within no more than two minutes after step (e) began.
18. The method of claim 13 , wherein step (d) of filling the cavity with the ozone gas to displace a mass of air out through the second opening comprises filling at least 90% of the cavity with ozone gas.
19. The method of claim 13 , wherein step (d) of filling the cavity with the ozone gas to displace a mass of air out through the second opening comprises filling at least 95% of the cavity with ozone gas.
20. The method of claim 13 , wherein the molding of the outer shell utilizes a rotational molding process.
21. The method of claim 13 , wherein the polymer is polyethylene.
22. The method of claim 13 , wherein the gas is air.
23. The method of claim 13 , wherein the first opening is adjacent a bottom portion of the internal cavity and the second opening is adjacent a top portion of the internal cavity.
24. A method for manufacturing a cooler, comprising:
(a) molding an external structure of the cooler from polyethylene, the external structure comprising:
an inner trough;
an outer shell coupled to the inner trough by a top edge surface;
an internal cavity spaced between the inner trough and the outer shell and extending around four sides and a base of the external structure;
a first opening extending into the internal cavity at a first corner of a base surface of the outer shell;
a second opening extending into the internal cavity at a second corner, opposite the first corner, of the base surface of the outer shell;
(b) positioning the external structure such that the second opening is above the first opening;
(c) injecting an ozone gas containing 5-7.5% ozone into the first opening;
(d) filling at least 90% of the cavity with the ozone gas in at least four minutes to displace a mass of air out through the second opening;
(e) flushing the cavity with air for at least two minutes to remove ozone gas from the cavity; and
(f) filling the cavity with polyurethane insulating foam.
25. The method of claim 24 , wherein the outer shell has a substantially cuboidal shape.