A flat, permeable, self-winding membrane, composed of a matrix formed of collagen fibers in a predetermined cross-linked and flattened, said matrix self-coils in a predetermined form when it absorbs an aqueous fluid and is permeable to molecules that they have molecular weights of less than 1 x 106 daltons.Una membrana de tipo lámina plana, permeable, autoenrollable, compuesta por una matriz formada por fibras de colágeno reticuladas en una forma predeterminada y aplanadas, dicha matriz se autoenrolla en una forma predeter-minada cuando absorbe un fluido acuoso y es permeable a las moléculas que tienen pesos moleculares inferiores a 1 x 106 daltones.
