Hydrogel Wound Covering with Stretchability and Exudate Absorption

The patent uses a composite structure combining polyurethane film (for stretchability) with hydrophilic colloid particles (for absorbency). The hydrogel layer contains both the elastic polyurethane matrix and water-absorbing hydrophilic colloid, creating a material that simultaneously provides stretchability and exudate absorption capability, resolving the contradiction between these two properties.

The patent applies different functional properties to different components of the composite material: the polyurethane film provides mechanical stretchability and elasticity, while the hydrophilic colloid particles provide absorbency. Each component performs its specific function locally within the composite structure, allowing both stretchability and absorbency to coexist without compromising either property.

The patent maintains transparency by using a hydrogel formulation where the hydrophilic colloid particles are dispersed within a transparent polyurethane matrix. The hydrogel layer itself remains transparent while the hydrophilic particles provide absorbency, allowing the wound surface to be observed through the material without compromising absorbency capability.

The patent controls the concentration and size parameters of hydrophilic colloid particles within the hydrogel to maintain transparency. By optimizing these parameters, the material achieves sufficient absorbency while keeping the overall structure transparent, preventing gel-like residues from forming on the wound surface.

The patent modifies the tackiness parameter by adjusting the composition and concentration of hydrophilic colloid particles within the hydrogel. By optimizing these parameters, the material achieves appropriate absorbency while controlling tackiness to a level that does not cause pain or damage to regenerated skin during replacement.

The patent distributes hydrophilic colloid particles throughout the polyurethane matrix, creating a uniform structure where absorbency is provided locally by the particles while the overall material properties (including tackiness) are controlled by the matrix composition. This local distribution prevents excessive tackiness concentration that would cause skin damage.

The patent creates a composite hydrogel material combining PVA hydrogel (for moisture maintenance and transparency) with hydrophilic colloid particles (for enhanced tackiness). This composite structure provides both the moisture-maintaining properties of PVA hydrogel and the improved tackiness needed for fixation without requiring additional bandages or surgical tapes.

The patent merges the functions of moisture maintenance and enhanced tackiness into a single integrated hydrogel material. By combining PVA hydrogel with hydrophilic colloid particles, the material simultaneously provides moisture-maintaining ability and sufficient tackiness for fixation, eliminating the need for separate fixation members.

The patent uses a composite structure where alginate gel particles are dispersed within a polyurethane hydrogel matrix. This composite provides the absorbency and hemostatic effects of alginate while the polyurethane matrix provides structural integrity and moisture maintenance without requiring additional film covering, as the hydrogel itself maintains the moist environment.

The patent creates a multi-functional hydrogel material that simultaneously provides absorbency, hemostatic effect, and moisture maintenance in a single material. The alginate particles provide absorbency and hemostasis, while the hydrogel matrix provides moisture maintenance, eliminating the need for separate film covering and reducing overall device complexity.