Skin-contact product having moisture and microclimate control

Abstract

Skin-contact products with a transpiration function such as medical devices or medicinal products, of which face masks, aspirators, ventilators, breast pumps or wound dressings are examples are described especially a skin-contact product with a transpiration function with an improved microclimate at a patient interface material-skin contact area. In an embodiment a material system (10, 20, 30) is described that comprises a hydrophobic silicone base material (11, 21, 31) and a hydrophilic silicone material (12, 22, 32) that is combined with the hydrophobic base material (11, 21, 31). At least a part of the hydrophilic material (12, 22, 32) is in contact with a moist surface (50). The hydrophobic base material (11, 21, 31) provides mechanical and dynamical stability of the material system (10, 20, 30). The hydrophilic material (12, 22, 32) allows for uptake or for diffusion of moisture away from moist surface (50). The material system (10, 20, 30) is utilized to fabricate a patient interface material (41) and forehead pad (42) of a user or patient interface, such as face mask (40), for example, a patient interface mask for positive air pressure therapy. Furthermore, a novel composition for the preparation of hydrophilic silicone materials, suitable for use in the material system (10, 20, 30), is disclosed.

Description

FIELD OF THE INVENTION[0001]The present invention relates to skin-contact products with moisture and microclimate control such as medical devices or medicinal products, especially user or patient interface devices of which face masks, respiratory masks, aspirators, ventilators, breast pumps or wound dressings are examples and, more particularly, to a skin-contact product with a transpiration function with an improved microclimate at a patient interface-skin contact area.BACKGROUND OF THE INVENTION[0002]There are many medical applications which require gas exchange, e.g. pressure to be applied to the skin of a human or other animal over a long period of time where a microclimate is created that may be uncomfortable for the wearer. Examples are patient interface devices, respiratory masks, aspirators, ventilators, breast pumps, and wound dressings.[0003]An exemplary medical application relates to a patient interface device used for ventilation for positive air pressure or oxygen deliv...

AI Technical Summary

Benefits of technology

The present invention provides a skin-contact product with moisture and microclimate control that prevents moisture accumulation and stratum corneum hyper-hydration, which can lead to a decrease in skin strength. The use of a special material system for the product reduces the risk of skin damage and improves the comfort of the patient interface device. This material system can be used to fabricate the patient interface mask for positive air pressure therapy of obstructive sleep apnea. The hydrophobic silicone base material provides mechanical and dynamical stability while the hydrophilic silicone material allows for uptake and diffusion of moisture away from the patient interface device-skin interface.

Problems solved by technology

Many people find wearing the patient interface device uncomfortable to such an extent that use of the device is discontinued.

Wearing a patient interface device, patients are reporting skin irritation, red marks and skin breakdown.

The recovery time varies from minutes to hours but in extreme cases, longer-lasting skin damage and pressure sores can occur.

These skin problems result in low patient compliance with patient interface devices and CPAP therapy.

The root causes for formation of red marks in the face of a person wearing a patient interface device are manifold and not yet fully understood.

Common factors reported in tissue breakdown are excessive mechanical skin load by pressure, shear and friction.

Reperfusion injury: after unloading, accumulated free radicals are released and cause inflammation and cell damage.

Lymphatic function impairment: occlusion and damage of the lymph vessels prevents the removal of metabolic waste, leading to tissue necrosis.

Moisture accumulation in the skin due to coverage of the skin decreases the skin strength to damage.

These materials are intrinsically hydrophobic and have very low water permeability, and, thus, do not provide a suitable environment for growth of bacteria and harmful bio-films.

While a tight seal is desired, the hydrophobic materials are not very suitable to allow transport of moisture and sweat, which attributes to the red mark formation and discomfort.

Accordingly, this material does not allow for the uptake of moisture or diffusion of moisture through the material and moisture can, thus, not be removed effectively from a contact area.

More generally, many commercial polymers are not skin friendly as they do not absorb water or sweat from the skin.

However alpha-olefin sulfonate surfactants, although having a vinyl functional group, do not easily mix with the monomer of commercial polymers like polyethylene (PE), polypropylene (PP), polybutadiene, polyisoprene, polystyrene (PS), polyacetonitrile (PAN), silicones, poly(meth)acrylates, polyacrylonitrile, acrylonitrile-butadiene-styrene copolymers (ABS) and styrene-acrylonitrile copolymers (SAN).

This incompatibility can be due to differences in boiling points, making these non volatile surfactants nearly impossible to use in gas phase polymerizations.

Even under liquid phase polymerization conditions, it is difficult to mix a hydrophilic surfactant containing a sulfonic acid salt with a hydrophobic monomer or pre-polymer.

However polyvinyl chloride is not regarded as a skin-compatible polymer.

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