Article of footwear with lightweight sole assembly

• US 7,941,938 B2
• Filed: 05/23/2007
• Issued: 05/17/2011
• Est. Priority Date: 05/26/2006
• Status: Active Grant

• Current Assignee: Nike, Inc.
• Original Assignee: Nike, Inc.
• Inventors: DeSpain, Daniel, Avar, Eric P., Schiller, Denis, Hoffer, Kevin W., Yu, Sui-Chieh, Jones, David Patrick
• Primary Examiner(s): PATTERSON, MARIE D
• Application Number:
  US11/752,348
• Publication Number:
  US 20080244926A1
• Time in Patent Office: 1,455 Days
• Field of Search: 36/28, 36/31, 36/30.R, 36/30.A, 36/25.R
• US Class Current: 36/25.00R
• CPC Class Codes: A43B 13/04 Plastics, rubber or vulcanised fibre
• CPC Class Codes: A43B 13/125 characterised by the midsole or middle layer
• CPC Class Codes: A43B 13/186 Differential cushioning region, e.g. cushioning located under the ball of the foot resilient heel not included in the sole A43B21/26; resilient supports for the heel of the foot A43B21/32
• CPC Class Codes: A43B 13/187 Resiliency achieved by the features of the material, e.g. foam, non liquid materials
• CPC Class Codes: A43B 13/188 Differential cushioning regions
• CPC Class Codes: A43B 7/1415 characterised by the location under the foot
• CPC Class Codes: C08J 2309/02 Copolymers with acrylonitrile
• CPC Class Codes: C08J 2323/02 not modified by chemical after treatment
• CPC Class Codes: C08J 2333/20 Homopolymers or copolymers of acrylonitrile C08J2355/02 takes precedence
• CPC Class Codes: C08J 2409/02 Copolymers with acrylonitrile
• CPC Class Codes: C08J 2423/02 not modified by chemical after treatment
• CPC Class Codes: C08J 2423/08 Copolymers of ethene C08J2423/16 takes precedence
• CPC Class Codes: C08J 2433/20 Homopolymers or copolymers of acrylonitrile C08J2455/02 takes precedence
• CPC Class Codes: C08J 9/0061 characterized by the use of several polymeric components
• CPC Class Codes: C08L 15/005 Hydrogenated nitrile rubber
• CPC Class Codes: C08L 2203/14 used for foams
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 2205/025 containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure
• CPC Class Codes: C08L 23/00 Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 2312/00 : Crosslinking
• CPC Class Codes: C08L 2666/02 : Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/24 : Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
• CPC Class Codes: C08L 53/02 : of vinyl-aromatic monomers and conjugated dienes
• CPC Class Codes: C08L 53/025 : modified
• CPC Class Codes: C08L 9/02 : Copolymers with acrylonitrile

Abstract

An article of footwear includes an upper and a sole assembly secured to the upper. The sole assembly includes a first portion having a lower ground engaging surface, an upper surface, and a recess formed in the upper surface. The upper surface of the first portion is in contact with the upper. A second portion is seated in the recess in the first portion and has an upper surface, with the upper surface of the second portion being in contact with the upper. The second portion comprises a foam material having a density less than 0.25 g/cm³.

Claims

1. An article of footwear comprising, in combination:

an upper;

a sole assembly secured to the upper and comprising;

a first portion having a lower ground engaging surface, an upper surface, and a recess formed in the upper surface, the upper surface of the first portion in contact with the upper; and

a second portion seated in the recess in the first portion and having an upper surface, the upper surface of the second portion in contact with the upper,

wherein the second portion is formed from a first foam material comprising a reaction product of about 10 to about 100 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, 0 to about 40 phr modified hydrogenated acrylonitrile butadiene copolymer, and 0 to about 90 phr alpha olefin copolymer, and at least one additive in an amount suitable to form the foam material;

wherein the hardness of the first foam material is 25 to 45 Asker C and the density of the first foam material is less than about 0.15 g/cm³.

2. The article of footwear of claim 1, wherein the first foam material comprises about 30 to about 90 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, about 5 to about 30 phr modified hydrogenated acrylonitrile butadiene copolymer, and about 20 to about 40 phr alpha olefin copolymer.

3. The article of footwear of claim 1, wherein the modified hydrogenated acrylonitrile butadiene copolymer is modified with zinc oxide, zinc diacrylate, or both.

4. The article of footwear of claim 1, wherein the alpha olefin copolymer is a copolymer of ethylene and an alpha olefin having 3 to 20 carbon atoms.

5. The article of footwear of claim 4, wherein the alpha olefin copolymer is selected from copolymers of ethylene and 1-octane.

6. The article of footwear of claim 1, wherein the first foam material has a hardness of 25 to 35 Asker C.

7. The article of footwear of claim 1, wherein the first foam material has a hardness of 35 to 45 Asker C.

8. The article of footwear of claim 1, wherein the first portion has a density greater than a density of the second portion.

9. The article of footwear of claim 1, wherein the first portion comprises ethylene vinyl acetate or a blend of ethylene vinyl acetate and rubber.

10. The article of footwear of claim 1, wherein the first portion comprises a second foam material comprising a reaction product of about 10 to about 100 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, 0 to about 40 phr modified hydrogenated acrylonitrile butadiene copolymer, and 0 to about 90 phr alpha olefin copolymer, and at least one additive in an amount suitable to form the foam material;

wherein the density of the second foam material is greater than the density of the first foam material.

11. The article of footwear of claim 1 wherein the density of the second foam material is greater than 0.10 g/cm³.

12. The article of footwear of claim 1, wherein the upper surface of the first portion is secured to the upper.

13. The article of footwear of claim 1, wherein the upper surface of the second portion is secured to the upper.

14. The article of footwear of claim 1, wherein the recess extends across all but a peripheral portion of the first portion.

15. The article of footwear of claim 1, wherein the first portion comprises a heel portion, a midfoot portion and a forefoot portion, the recess extending from a rear of the heel portion to a front of the forefoot portion.

16. The article of footwear of claim 1, wherein the lower ground engaging surface includes a plurality of projections.

17. The article of footwear of claim 1, further comprising a plurality of grooves formed in the lower ground engaging surface, each groove extending about a periphery of a corresponding projection.

18. The article of footwear of claim 1, further comprising a plurality of ribs extending substantially horizontally along a sidewall of the sole assembly.

19. The article of footwear of claim 1 wherein the ribs extend outwardly from the first portion.

20. An article of footwear comprising, in combination:

an upper;

a sole assembly secured to the upper and comprising;

a first portion having a lower ground engaging surface, an upper surface, a recess formed in the upper surface, the upper surface of the first portion being secured to the upper, and being formed of a material having a first density; and

a second portion seated in the recess in the first portion, having an upper surface secured to the upper, and being formed of a material having a second density, the second density being less than the first density,

wherein the second portion is a foam material comprising a reaction product of about 10 to about 100 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, 0 to about 40 phr modified hydrogenated acrylonitrile butadiene copolymer, and 0 to about 90 phr alpha olefin copolymer, and at least one additive in an amount suitable to form the foam material;

wherein the hardness of the first foam material is 25 to 45 Asker C and the density of the foam material is less than about 0.15 g/cm³.

21. The article of footwear of claim 20, wherein the first foam material has a hardness of 25 to 35 Asker C.

22. The article of footwear of claim 20, wherein the first foam material has a hardness of 35 to 45 Asker C.

23. A sole assembly comprising:

a first portion having a lower ground engaging surface, an upper surface, and a recess formed in the upper surface; and

a second portion seated in the recess in the first portion and having an upper surface,

wherein the second portion is formed from a first foam material comprising a reaction product of about 10 to about 100 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, 0 to about 40 phr modified hydrogenated acrylonitrile butadiene copolymer, and 0 to about 90 phr alpha olefin copolymer, and at least one additive in an amount suitable to form the foam material;

wherein the hardness of the first foam material is 25 to 45 Asker C and the density of the first foam material is less than about 0.15 g/cm³.

24. The article of footwear of claim 23, wherein the first foam material has a compression set less than 50% and a resiliency greater than 40%.

25. The sole assembly of claim 23, wherein the first portion has a density greater than a density of the second portion.

26. The sole assembly of claim 23, wherein the first portion is formed from a first foam material comprising a reaction product of about 10 to about 100 phr hydrogenated or non-hydrogenated acrylonitrile butadiene copolymer, 0 to about 40 phr modified hydrogenated acrylonitrile butadiene copolymer, and 0 to about 90 phr alpha olefin copolymer, and

at least one additive in an amount suitable to form the foam material;

wherein the density of the second foam material is greater than the first foam material.

27. The sole assembly of claim 23, wherein the recess extends across all but a peripheral portion of the first portion.

28. The sole assembly of claim 23, wherein the first portion comprises a heel portion, a midfoot portion and a forefoot portion, the recess extending from a rear of the heel portion to a front of the forefoot portion.

29. The sole assembly of claim 23, wherein the lower ground engaging surface includes a plurality of projections.

30. The sole assembly of claim 23, further comprising a plurality of grooves formed in the lower ground engaging surface, each groove extending about a periphery of a corresponding projection.

31. The sole assembly of claim 23, further comprising a plurality of ribs extending substantially horizontally along a sidewall of the sole assembly.

32. The sole assembly of claim 23, wherein the ribs extend outwardly from the first portion.

33. The sole assembly of claim 23, wherein the first foam material has a hardness of 25 to 35 Asker C.

34. The sole assembly of claim 23, wherein the first foam material has a hardness of 35 to 45 Asker C.