Method of manufacturing disposable cold pack and related disposable cold pack containing urea and ammonium chloride

A disposable cold pack for providing cold therapy to a portion of a body, the cold pack comprising:

• an outer pack formed of a water-tight sealed envelope, the outer pack having an outer surface configured for placement on skin or clothing covering the portion of the body;
• a mixture of urea and ammonium chloride contained inside the outer pack;
• and
• a water-tight frangible container disposed inside the outer pack, the water-tight frangible container containing water, the water-tight frangible container configured to release the water into the inside of the outer pack in response to an external force applied to the outer pack;
• relative proportions of the urea, the ammonium chloride, and the water selected to provide a target cooling effect to the portion of the body.

A disposable cold pack for providing cold therapy to a portion of a body, the cold pack comprising:

• an outer pack formed of a water-tight sealed envelope formed of at least one layer of plastic sheet that is heat-sealed at one or more heat-sealed seams, the plastic sheet having a fibre texture at an outer surface of the outer pack to configure the outer pack for placement in direct contact with skin of the portion of the body;
• a mixture of urea and ammonium chloride contained inside the outer pack, the mixture not containing a substantial amount of ammonium nitrate;
• and
• a water-tight frangible container disposed inside the outer pack, the water-tight frangible container including a heat-sealed plastic bag containing water, the water-tight frangible container configured to rupture and release the water into the inside of the outer pack in response to an external force applied to the outer pack;
• relative proportions of the urea, the ammonium chloride, and the water selected to provide a target cooling effect to the portion of the body, the relative proportions being between about 32-38% urea, between about 7-16.5% ammonium chloride, and between about 45.5-61% water, by weight.