Patent ID: 7741476

Claim:
Process of preparing a cross-linked polymer comprising 1) forming a mixture of a first hyaluronic acid salt product having a first molecular weight and a second hyaluronic acid salt product having a second molecular weight greater than the first molecular weight, wherein the first hyaluronic acid salt product and the second hyaluronic acid salt product are two separate pre-existing products prior to the forming step; and 2) cross-linking the mixture of step 1) in an aqueous solvent in the presence of an effective and non-excessive amount of at least one cross-linking agent, such that the degree of cross-linking, defined by the ratio: 100×(total number of reactive groups in said cross-linking agent/total number of disaccharide units in the first hyaluronic acid salt and second hyaluronic acid salt), is theoretically between 0.5 and 70%.