Hydrogel materials for hot and cold therapy and method for forming same

• US 4,668,564 A
• Filed: 01/31/1986
• Issued: 05/26/1987
• Est. Priority Date: 12/26/1985
• Status: Expired due to Term

• Current Assignee: Nationsbank NA (Bank of America Corp.)
• Original Assignee: Spenco Medical
• Inventors: Orchard, Lewis P.
• Primary Examiner(s): VAN BALEN, WILLIAM
• Application Number:
  US06/824,492
• Time in Patent Office: 480 Days
• Field of Search: 128/155, 128/156, 428/68, 428/71, 428/76, 428/304.4, 428/306.6, 428/316.6, 428/246, 428/308.4, 524/767, 604/368, 604/369, 604/890, 604/896, 604/897, 264/46.4, 427/373
• US Class Current: 442/226
• CPC Class Codes: A61F 7/02 Compresses or poultices for effecting heating or cooling
• CPC Class Codes: A61K 47/34 Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds, e.g. polyesters, polyamino acids, polysiloxanes, polyphosphazines, copolymers of polyalkylene glycol or poloxamers A61K47/10 takes precedence
• CPC Class Codes: A61K 9/70 Web, sheet or filament bases ; Films; Fibres of the matrix type containing drug hollow drug-filled fibres A61K9/0092
• CPC Class Codes: A61L 15/26 Macromolecular compounds obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof A61L15/225 takes precedence
• CPC Class Codes: A61L 15/60 Liquid-swellable gel-forming materials, e.g. super-absorbents
• CPC Class Codes: A61L 26/0019 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 26/008 Hydrogels or hydrocolloids
• CPC Class Codes: B32B 2266/06 Open cell foam
• CPC Class Codes: B32B 2307/30 having particular thermal properties
• CPC Class Codes: B32B 5/18 characterised by features of a layer of foamed material
• CPC Class Codes: B32B 5/24 one layer being a fibrous or filamentary layer
• CPC Class Codes: B32B 5/245 another layer next to it being a foam layer
• CPC Class Codes: C08G 18/10 Prepolymer processes involving reaction of isocyanates or isothiocyanates with compounds having active hydrogen in a first reaction step
• CPC Class Codes: C08G 18/3206 aliphatic
• CPC Class Codes: C08G 18/4833 Polyethers containing oxyethylene units
• CPC Class Codes: C08G 2210/00 Compositions for preparing hydrogels
• CPC Class Codes: C08L 75/04 Polyurethanes
• CPC Class Codes: F25D 3/08 portable, i.e. adapted to be carried personally
• CPC Class Codes: Y10T 428/249953 Composite having voids in a component [e.g., porous, cellular, etc.]
• CPC Class Codes: Y10T 428/249958 Void-containing component is synthetic resin or natural rubbers
• CPC Class Codes: Y10T 428/249981 : Plural void-containing components
• CPC Class Codes: Y10T 442/3366 : Woven fabric is coated, impregnated, or autogenously bonded

Abstract

A hot or cold compress a layer of substituted urea/urethane hydrogel material bonded to a porous substrate. The hydrogel material is made up of a high molecular weight polyol, a toluene diisocyanate prepolymer and water. Generally, the water and polyol each comprises between about 40 to 50% by weight of the hydrogel, with the diisocyanate prepolymer making up the remaining 12-16% by weight. The hot or cold compresses of the present invention are formed by preparing the hydrogel material and then placing a porous substrate in contact with the hydrogel prior to the time that gel formation is complete. In this manner, the hydrogel becomes integrally bonded to the porous substrate. Other materials such as terrycloth can be bonded to the porous substrate prior to bonding the substrate to the hydrogel. Articles useful in therapy can then be formed by attaching the edges of the cloth/porous substrate to form the desired object.

Claims

1. A hot or cold compress comprising a layer of a substituted urea/urethane hydrogel material bonded to first side of a porous substrate and absent the opposing side of said substrate, said layer of hydrogel comprising between approximately 20 to 80% weight water, approximately 10 to 60% by weight of a weight polyol and approximately 10 to 20% by weight of a diisocyanate prepolymer.

2. The compress of claim 1 wherein said water is present in an amount of between about 40 to 50% by weight, said polyol is present in an amount of between about 10 to 50% by weight and said diisocyanate prepolymer is present in an amount between about 10 to 20% by weight.

3. The compress of claim 2 wherein said water and said polyol are present in an amount of between about 40 to about 50% by weight and said diisocyanate prepolymer is present in an amount of between about 12 to 16% by weight.

4. The compress of claim 3 wherein said water and said polyol are present in an amount of about 43% by weight and said diisocyanate prepolymer is present in an amount of about 14% by weight.

5. The compress of claim 1 wherein said porous substrate commprises a substantially open-celled foam material.

6. The compress of claim 1 wherein said porous substrate comprises a polyether-based, recticulated urethane foam.

7. The compress of claim 1 wherein said porous substrate comprises a polyester-based urethane foam.

8. The compress of claim 1 wherein said polyol is selected from the group comprising propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol or mixtures thereof.

9. The compress of claim 8 wherein the polyol is propylene glycol.

10. The compress of claim 1 wherein the diisocyanate prepolymer comprises a toluene diisocyanate prepolymer.

11. The compress of claim 1 wherein the porous substrate further comprises a layer of cloth bonded to said porous substrate.

12. The compress of claim 1 wherein said compress is configured in the shape of a stocking cap.

13. The compress of claim 1 wherein the compress is configured in the shape of a mitten.

14. The compress of claim 1 wherein said compress is a rectangular solid having means for attaching said compress to a head.

15. The compress of claim 1 wherein said hydrogel material is impregnated with medication.

16. The compress of claim 15 wherein said medication is methylsalycilate and wherein said substrate is configured in the shape of a strap useful for applying said compress to a portion of a wearer'"'"'s body.

17. A method for forming objects having a substituted urea/urethane hydrogel layer bonded to a first side of a layer of porous substrate and absent the opposing side of said substrate, comprising:

preparing said hydrogel material;

contacting said first side of porous substrate with said hydrogel material prior to complete gel formation of said hydrogel;

maintaining said layer of porous substrate in contact with said hydrogel material until gel formation is substantially complete, thereby bonding said porous substrate material to the hydrogel material; and

forming a desired object from said hydrogel bonded to said porous substrate.

18. The method of claim 17 further comprising introducing said hydrogel material into a mold having a desired shape prior to contacting said porous substrate with said hydrogel.

19. The method of claim 17 wherein said hydrogel is prepared by mixing between approximately 10 to 20% by weight of a diisocyanate prepolymer with approximately 10 to 60% by weight of a high molecular weight polyol, and then adding between approximately 20 to 80% by weight water to said diisocyanate/polyol mixture.

20. The method of claim 19 wherein said diisocyanate prepolymer is present in an amount of between about 10 to 20% by weight, said polyol is present in an amount of between about 10 to 50% by weight and said water is present in an amount of between about 40 to 50% by weight.

21. The method of claim 19 wherein said prepolymer is present in an amount of between about 12 to 15% by weight and said water and said polyol are present in an amount of between about 40 to 50% by weight.

22. The method of claim 19 wherein said prepolymer is present in an amount of about 14% by weight and said water and said polyol are present in an amount of approximately 43% by weight.

23. The method of claim 17 wherein said porous substrate comprises a substantially open-celled foam material.

24. The method of claim 17 wherein said porous substrate comprises a urethane foam.

25. The method of claim 17 wherein said porous substrate is a polyether-based, recticulated urethane foam.

26. The method of claim 17 wherein said porous substrate is a polyester-based urethane foam.

27. The method of claim 19 wherein said polyol is selected from the group comprising propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol, or mixtures thereof.

28. The method of claim 27 wherein said polyol is propylene glycol.

29. The method of claim 19 wherein said diisocyanate prepolymer comprises a toluene diisocyanate prepolymer.

30. The method of claim 17 wherein said porous substrate further comprises a cloth material bonded thereto.

31. The method of claim 30 wherein said cloth material is terrycloth.

32. The method of claim 17 wherein the desired object is a stocking cap.

33. The method of claim 17 wherein the object is a mitten.

34. The method of claim 17 wherein the object is a rectangular solid having means for attaching said rectangular solid to a head.

35. The method of claim 17 further comprising impregnating said hydrogel material with medication.

36. The method of claim 35 wherein said medication is methylsilicylate.

37. The product formed by the process recited in claim 17.

38. The product formed by the process recited in claim 19.

39. The product formed by the process recited in claim 22.

40. A method for bonding a substituted urea/urethane hydrogel material to a first side of a porous substrate material and absent the opposing side of said substrate comprising:

contacting said porous substrate material with said hydrogel material prior to the time that said hydrogel material has completely gelled; and

maintaining said porous substrate in contact with said hydrogel material until gel formation of the hydrogel is substantially complete, thereby bonding the porous substrate to the hydrogel material.

41. The method of claim 40 wherein said porous substrate material comprises a substantially open-celled foam.

42. The method of claim 40 wherein the porous substrate is a polyether-based, recticulated foam.

43. The method of claim 40 wherein the foam is a polyester-based urethane foam.

44. The method of claim 40 wherein said form has a layer of cloth material bonded thereto.

45. The method of claim 44 wherein said cloth material is flame bonded to said foam.