Patent ID: 8748579

Claim:
A method for preparing a collagen-based matrix, the method comprising: spreading a first atelocollagen dispersion or an infection-suppressive atelocollagen dispersion for a porous layer over a Petri dish or a releasable plate to form a uniform membrane followed by lyophilization to give a porous membrane; spreading a second atelocollagen dispersion for a dense layer over a releasable plate; applying an additional pressure of 1˜20 p.s.i. directly to the spread dispersion by a dense porous absorbent plate in contact with the spread dispersion such that water leaches out and collagen particles are brought into contact with each other to form a dense membrane; partially drying the dense membrane at a room temperature for 10˜20 minutes; overlaying the porous membrane on the partially dried dense membrane; completely air-drying the partially dried dense membrane together with the porous membrane to form a bilayer structure in which the porous membrane is bound to the dense membrane; immersing the bilayer structure in a solution containing a crosslinking agent to generate crosslinking between the porous membrane and the dense membrane in the bilayer structure; washing the bilayer structure to remove the crosslinking agent therefrom; and lyophilizing the washed bilayer structure.