Method for applying an exothermic coating to a substrate

• US 7,338,516 B2
• Filed: 12/23/2004
• Issued: 03/04/2008
• Est. Priority Date: 12/23/2004
• Status: Expired due to Fees

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Schorr, Phillip A., Quincy, Roger Bradshaw III
• Primary Examiner(s): Piziali; Andrew T
• Application Number:
  US11/022,299
• Publication Number:
  US 20060141882A1
• Time in Patent Office: 1,167 Days
• Field of Search: 442/152, 442/164, 442/172, 607/96, 752/28
• US Class Current: 607/96
• CPC Class Codes: A61F 7/034 Flameless
• CPC Class Codes: C09K 5/18 Non-reversible chemical reactions
• CPC Class Codes: D06N 3/0063 Inorganic compounding ingredients, e.g. metals, carbon fibres, Na2CO3, metal layers; Post-treatment with inorganic compounds
• CPC Class Codes: F24V 30/00 Apparatus or devices using heat produced by exothermal chemical reactions other than combustion
• CPC Class Codes: Y02P 70/62 related technologies for production or treatment of textile or flexible materials or products thereof, including footwear
• CPC Class Codes: Y10T 442/2762 Coated or impregnated natural fiber fabric [e.g., cotton, wool, silk, linen, etc.]
• CPC Class Codes: Y10T 442/2861 Coated or impregnated synthetic organic fiber fabric
• CPC Class Codes: Y10T 442/2926 Coated or impregnated inorganic fiber fabric

Abstract

A substrate that is capable of generating heat upon activation is provided. Specifically, the substrate is applied with an exothermic coating that may be formed from a variety of different components, including oxidizable metals, carbon components, binders, electrolytic salts, moisture-retaining particles, and so forth. The oxidizable metal is capable of undergoing an exothermic reaction in the presence of oxygen and water to generate heat. To reduce the likelihood of premature activation prior to use, the exothermic coating is anhydrous, i.e., generally free of water. The coated substrate may be employed in a wide variety of articles, such as absorbent articles, thermal blankets, drapes, heating pads etc.

Claims

1. A substrate that contains an exothermic coating at a solids add-on level of from about 20% to about 5000%, said exothermic coating comprising an oxidizable metal powder in an amount of from about 40 wt. % to about 95 wt. % of said coating, a carbon component in an amount from about 0.01 wt. % to about 20 wt. % of said coating, a binder in an amount from about 0.01 wt. % to about 20 wt. % of said coating, an electrolytic salt in an amount from about 0.01 wt. % to about 10 wt. % of said coating, and moisture-retaining particles in an amount from about 0.01 wt. % to about 30 wt. % of said coating, wherein the binder comprises a polymer latex, wherein the polymer latex is sufficiently crosslinked to be substantially insoluble in water, wherein said exothermic coating is capable of activation in the presence of oxygen and moisture to generate heat, and wherein said exothermic coating is generally free of water prior to activation.

2. The substrate of claim 1, wherein said metal powder contains iron, zinc, aluminum, magnesium, or combinations thereof.

3. The substrate of claim 1, wherein said carbon component is activated carbon.

4. The substrate of claim 1, wherein said binder further comprises a nonionic cellulosic ether.

5. The substrate of claim 1, wherein said electrolytic salt is a metal halide.

6. The substrate of claim 1, wherein said moisture-retaining particles include calcium carbonate.

7. The substrate of claim 1, wherein the solids add-on level is from about 100% to about 1200%.

8. The substrate of claim 1, wherein said metal powder constitutes from about 50 wt. % to about 90 wt. % of said exothermic coating.

9. The substrate of claim 1, wherein said carbon component constitutes from about 0.1 wt. % to about 15 wt. % of said exothermic coating.

10. The substrate of claim 1, wherein said binder constitutes from about 0.1 wt. % to about 10 wt. % of said exothermic coating.

11. The substrate of claim 1, wherein said electrolytic salt constitutes from about 0.5 wt. % to about 5 wt. % of said exothermic coating.

12. The substrate of claim 1, wherein the substrate contains a nonwoven fabric, woven fabric, knit fabric, paper web, film, foam, or combination thereof.

13. The substrate of claim 1, wherein the substrate contains a nonwoven web.

14. The substrate of claim 1, wherein said moisture-retaining particles are porous.

15. The substrate of claim 1, wherein said moisture-retaining particles have a size of less than about 100 micrometers.

16. The substrate of claim 1, wherein said moisture-retaining particles constitute from about 0.1 wt. % to about 20 wt. % of said coating.