Abstract A comparatively thick sheet of a spongy hydrogel, made, e.g., by polymerizing ethylene glycol monomethacrylate in presence of less than 2 percent of a cross-linking agent and more than 60 percent of water, is laminated with a much thinner sheet of the same or similar, but homogeneous hydrogel, either from one side or from both sides. Alternatively, one external layer may be less hydrophilic or fully hydrophobic. The lamination is carried out so that the external thin layer is made on a glass or other smooth pad, either by polymerizing a cross-linked or linear polymer thereon, or by casting a thin layer of a dissolved linear polymer. Then a monomer mixture for spongy hydrogel is cast onto the first layer and polymerized. A sandwich structure is obtained if the monomer mixture for spongy hydrogel is cast between two pads provided with a thin homogeneous polymer layer. Hydrogel laminates and sandwich structures are useful, e.g., for surgical and cosmetic purposes, for filtering liquids, etc.
A LAMINATE PRODUCT COMPRISING AT LEAST (A) ONE PREFORMED FILM LAYER OF AN INITIALLY SOLUBLE NON-CROSSLINKED HOMOGENEOUS POLYMER FORMED FROM A SOLUTION OF A COPOLYMER OF ETHYLENE GLYCOL MONOMETHACRYLATE WITH ETHYLENE GLYCOL DIMETHACRYLATE AND ADHERE THERETO (B) A TICKER LAYER OF A SPONGY HYDROPHILIC HYDROGEL POLYMERIZED IN-SITU THEREON, SAID HYDROGEL BEING FORMED FROM A MIXTURE CONTAINING AT LEAST 60 PERCENT BY WEIGHT OF WATER AND A COPOLYMER OF A GLYCOL MONOMETHACRYLATE MONOMER SELECTED FROM THE GROUP CONSISTING OF ETHYLENE GLYCOL MONOMETHACRYLATE, DIETHYLENE GLYCOL MONOMETHACRYLATE, TRIETHYLENE GLYCOL MONOMETHACRYLATE AND MIXTURES THEREOF, PROPYLENE GLYCOL MONOMETHACRYLATE, AND COPOLY-CONDENSATES THEREOF WITH ETHYLENE GLYCOL WITH UP TO 2 CENT ETHYLENE GLYCOL DIMETHACRYLATE FORMED IN THE PERSENCE OF A POLYMERIZATION INITATOR, SAID TWO LAYERS BEING BOND TOGETHER AS A RESULT OF SAID POLYMERIZATION, SAID FILM LAYER (A) RENDERED SUBSTANTIALLY INSOLUBLE BY THE EXISTENCE OF CHEMICAL BONDS FORMED BY CROSS-LINKING DURING POLYMERIZATION OF THE MONOMER MIXTURE FOR SAID SPONGY HYDROGEL WITH SAID FILM LAYER
Claim 2
Dependent Claim
157 words
A LAMINATE PRODUCT COMPRISING AT LEAST (A) ONE PREFORMED FILM LAYER OF AN INITIALLY SOLUBLE NON-CROSSLINKED HOMOGENEOUS POLYMER FORMED FROM A SOLUTION OF A COPOLYMER OF ETHYLENE GLYCOL MONOMETHACRYLATE WITH ETHYLENE GLYCOL DIMETHACRYLATE AND ADHERE THERETO (B) A TICKER LAYER OF A SPONGY HYDROPHILIC HYDROGEL POLYMERIZED IN-SITU THEREON, SAID HYDROGEL BEING FORMED FROM A MIXTURE CONTAINING AT LEAST 60 PERCENT BY WEIGHT OF WATER AND A COPOLYMER OF A GLYCOL MONOMETHACRYLATE MONOMER SELECTED FROM THE GROUP CONSISTING OF ETHYLENE GLYCOL MONOMETHACRYLATE, DIETHYLENE GLYCOL MONOMETHACRYLATE, TRIETHYLENE GLYCOL MONOMETHACRYLATE AND MIXTURES THEREOF, PROPYLENE GLYCOL MONOMETHACRYLATE, AND COPOLY-CONDENSATES THEREOF WITH ETHYLENE GLYCOL WITH UP TO 2 CENT ETHYLENE GLYCOL DIMETHACRYLATE FORMED IN THE PERSENCE OF A POLYMERIZATION INITATOR, SAID TWO LAYERS BEING BOND TOGETHER AS A RESULT OF SAID POLYMERIZATION, SAID FILM LAYER (A) RENDERED SUBSTANTIALLY INSOLUBLE BY THE EXISTENCE OF CHEMICAL BONDS FORMED BY CROSS-LINKING DURING POLYMERIZATION OF THE MONOMER MIXTURE FOR SAID SPONGY HYDROGEL WITH SAID FILM LAYER