Thermally insulating products for footwear and other apparel
View Patent ↗Articles of apparel comprising insulating components having insulating structures with low thermal conductivity. Preferred insulating components for use in apparel have an insulating structure comprising a gas impermeable envelope and a porous material contained within the envelope where the insulating structure has a thermal conductivity of less than or equal to 25 mW/m K.
1. A method of insulating a boot comprising
providing a boot having a toe cap area, a boot upper and a boot sole;
providing a mixture comprising a porous material selected from fumed metal oxide and aerogel;
compressing the mixture to form a structure material,
placing more than one section of the structure material in a gas impermeable envelope,
evacuating air from the envelope at reduced pressure, and sealing the envelope, to form a flat insulating structure comprising more than one section of structure material within the envelope;
sealing the envelope between sections of the structure material within the envelope to provide flexibility to the flat insulating structure for shaping;
shaping the flat insulating structure from a flat structure into the form of a shaped insulating structure; and
inserting the shaped insulating structure into the boot, the shaped insulating structure having a thermal conductivity of less than or equal to 25 mW/m K at 25° C.
2. The method of claim 1 , wherein the boot comprises inner and outer boot layers and the shaped insulating structure is positioned between the layers.
3. The method of claim 1 , wherein the shaped insulating structure is affixed to an inner boot layer and adjacent a wearer of the boot.
4. The method of claim 1 , wherein the flat insulating structure is shaped into the form of a curved shaped insulating structure that corresponds to the toe cap area of the boot.
5. The method of claim 1 , wherein the gas impermeable envelope is under a vacuum pressure of up to about 10,000 Pa.
6. The method of claim 1 , wherein the gas impermeable envelope is under a vacuum pressure of about 1,000 Pa or less.
7. The method of claim 1 , wherein the method comprises forming the flat insulating structure having a thickness of less than 3 mm.
8. The method of claim 1 , wherein the method comprises forming the flat insulating structure having a thickness of 2 mm or less.
9. A method of insulating a boot comprising
providing a boot having a toe cap area, a boot upper and a boot sole;
providing a mixture comprising a porous material selected from fumed metal oxide and aerogel;
compressing the mixture to form a structure material,
placing more than one section of the structure material in a gas impermeable envelope,
evacuating and sealing the envelope at reduced pressure, to form a flat insulating structure comprising more than one section of structure material within the envelope;
sealing the envelope between sections of the structure material within the envelope to provide flexibility to the flat insulating structure for shaping;
shaping the flat insulating structure from a flat insulating structure into a form of a shaped insulating structure; and
inserting the shaped insulating structure into the toe cap area of the boot, the shaped insulating structure having a thermal conductivity of less than or equal to 25 mW/m K at 25° C.
10. The method of claim 9 , wherein the flat insulating structure has a loss of thickness of 20% or less at a pressure of 1 atmosphere.
11. The method of claim 9 , wherein the flat insulating structure has a loss of thickness of 10% or less at a pressure of 1 atmosphere.
12. The method of claim 9 , wherein the porous material is a fumed metal oxide.
13. The method of claim 9 , wherein the porous material is fumed silica.
14. The method of claim 9 , wherein the porous material is fumed alumina.
15. The method of claim 9 , wherein the flat insulating structure is shaped into the form of a curved shaped insulating structure that corresponds to the toe cap area of the boot.
16. The method of claim 9 , wherein the gas impermeable envelope is under a vacuum pressure of up to about 10,000 Pa.
17. The method of claim 9 , wherein the gas impermeable envelope is under a vacuum pressure of about 1,000 Pa or less.
18. The method of claim 9 , wherein the boot comprises inner and outer boot layers, and the method further comprises positioning the insulating component between the inner and outer boot layers.
19. The method of claim 9 , wherein boot comprises an inner boot layer, and the method further comprises affixing the insulating component to the inner boot layer adjacent a wearer of the boot.
20. The method of claim 9 , wherein the method comprises forming the flat insulating structure having a thickness of less than 3 mm.
21. The method of claim 9 , wherein the method comprises forming the flat insulating structure having a thickness of 2 mm or less.