Occlusive wound care dressing

Claim 2

An occlusive dressing for care of skin wounds, which includes a skin contacting barrier layer and an overlying backing layer adhesively united thereto; said backing layer being formed from a thin sheet which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.5 pounds per inch of width, said barrier layer being formed from a composition composed essentially of: (a) an elastomeric phase integrated by a cross-linked polymer network; and (b) a particulate water-absorbing hydrocolloid phase dispersed in said cross-linked elastomeric phase, sufficient hydrocolloid being present to provide said barrier layer with a water absorbing capacity of from 3 to 12 grams per gram of barrier, said barrier layer swelling progressively as it absorbs aqueous fluid while remaining integrated and when saturated having substantially no adherence to the skin, whereby the portion of said barrier layer over the wound enlarges by stretching the backing sheet as it absorbs wound exudate and thereafter is removable in one piece with minimal irritation of the wound area.

Claim 3

The occlusive dressing of claim 1 in which said barrier layer contains an elastomeric copolymer of ethylene and vinyl acetate which has been cross-linked by gamma irradiation to provide said polymer network.

Claim 4

The occlusive dressing of claim 1 in which said backing layer is a foam material which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.0 pounds per inch of width.

Claim 5

An occlusive dressing for care of skin wounds, which includes a skin-contacting barrier layer and an overlying backing layer adhesively united thereto, said backing layer being formed from a thin sheet which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.2 pounds per inch of width, said barrier layer being formed from a composition composed essentially of: (a) an elastomeric phase integrated by a cross-linked polymer network; and (b) a particulate water-absorbing hydrocolloid phase dispersed in said cross-linked elastomeric phase, sufficient hydrocolloid being present to provide said barrier layer with a water absorbing capacity of from 4 to 8 grams per gram of barrier, said barrier layer swelling progressively as it absorbs aqueous fluid while remaining integrated and when saturated having substantially no adherence to the skin, whereby the portion of said barrier layer over the wound enlarges by stretching the backing sheet as it absorbs wound exudate and thereafter is removable in one piece with minimal irritation of the wound area.

Claim 6

An occlusive dressing for care of skin wounds, which includes a skin-contacting barrier layer and an overlying backing layer adhesively united thereto, said backing layer being formed from a thin sheet which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.2 pounds per inch of width, said barrier layer being formed from a composition composed essentially of: (a) an elastomeric phase integrated by a cross-linked polymer network; and (b) a particulate water-absorbing hydrocolloid phase dispersed in said cross-linked elastomeric phase, sufficient hydrocolloid being present to provide said barrier layer with a water absorbing capacity of from 4 to 8 grams per gram of barrier, said barrier layer swelling progressively as it absorbs aqueous fluid while remaining integrated and when saturated having substantially no adherence to the skin, whereby the portion of said barrier layer over the wound enlarges by stretching the backing sheet as it absorbs wound exudate and thereafter is removable in one piece with minimal irritation of the wound area.

Claim 7

The occlusive dressing of claim 3 in which the elastomeric phase of said barrier layer is primarily of a mixture of polyisobutylene (PIB) and said EVA copolymer.

Claim 8

The occlusive dressing of claim 3 in which said backing layer is an essentially closed cell foam material which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.0 pounds per inch of width.

Claim 9

The occlusive dressing of claim 3 in which said backing layer is a partially open cell foam material which permits the transmission of water vapor therethrough and which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress not over 1.0 pounds per inch of width.

Claim 10

An occlusive dressing for care of skin wounds, which includes a skin-contacting barrier layer and an overlying backing layer adhesively united thereto, said backing layer being formed from a thin sheet which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.0 pounds per inch of width, said barrier layer being formed from a composition composed essentially of: (a) an elastomeric phase composed primarily of a mixture of polyisobutylene (PIB) and a copolymer of ethylene and vinyl acetate (EVA) from 0.2 to 0.8 parts of said EVA being present per part of said PIB, said EVA having been cross-linked by gamma irradiation; and (b) a particulate water-absorbing hydrocolloid phase dispersed in said elastomeric phase, sufficient hydrocolloid being present to provide said barrier layer with a water absorbing capacity of from 4 to 8 grams of water per gram of barrier, said barrier layer swelling progressively as it absorbs aqueous fluid while remaining integrated up to saturation and having substantially no wet tack at saturation, whereby the portion of said barrier layer over the wound enlarges by stretching the backing sheet as it absorbs wound exudate, and when saturated is removable in one piece with minimal irritation of the wound area.

Claim 11

An occlusive dressing for care of skin wounds, which includes a skin-contacting barrier layer and an overlying backing layer adhesively united thereto, said backing layer being formed from a thin sheet which is stretchable to the extent that a 50% elongation without rupture is produced by a tensioning stress of not over 1.0 pounds per inch of width, said barrier layer being formed from a composition composed essentially of: (a) an elastomeric phase composed primarily of a mixture of polyisobutylene (PIB) and a copolymer of ethylene and vinyl acetate (EVA) from 0.2 to 0.8 parts of said EVA being present per part of said PIB, said EVA having been cross-linked by gamma irradiation; and (b) a particulate water-absorbing hydrocolloid phase dispersed in said elastomeric phase, sufficient hydrocolloid being present to provide said barrier layer with a water absorbing capacity of from 4 to 8 grams of water per gram of barrier, said barrier layer swelling progressively as it absorbs aqueous fluid while remaining integrated up to saturation and having substantially no wet tack at saturation, whereby the portion of said barrier layer over the wound enlarges by stretching the backing sheet as it absorbs wound exudate, and when saturated is removable in one piece with minimal irritation of the wound area.

Claim 12

The occlusive dressing of claim 8 in which said backing layer is a closed cell polyvinyl chloride foam having a thickness of from 25 to 35 mils.

Claim 13

The occlusive dressing of claim 8 in which said backing layer is a partially open cell polyurethane foam having a thickness of from 25 to 35 mils, said foam backing layer permitting the transmission of water vapor therethrough.

Claim 14

The occlusive dressing of claim 6 in which said backing sheet is a polyurethane film having a thickness of from 0.5 to 1.5 mils.

Claim 15

The occlusive dressing of claim 7 in which said backing sheet is a latex rubber film having a thickness of 2 to 15 mils.