Abstract: Method for the formation of hydrophilic layers on the surface of objects made from polymeric esters and/or nitriles of acrylic acid and/or methacrylic acid by means of hydrolysis caused by stron acids at elevated temperature, where the solubility of polymer in warm acid is reduced by addition of a salt which alone does not react with the polymer, advantageously of a salt of the used acid. The thickness of the hydrophilic layer may be controlled by changing the concentration of salt and the survace layer containing hydroxyl groups may be at the same time or subsequently thickened by treatment with a multifunctional primary or secondary alcohol, whereas the alcohol groups may be previosuly, at least in part, esterified with an acid which is weaker than is the acid used for hydrolysis.

Abstract: Contact lens or intraocular lens from lightly crosslinked polymer of 2-hydroxyethyl methacrylate or from such its copolymer, where the 2-hydroxyethyl methacrylate component prevails over the second nonhydrophilic component, which contains a hydrophilic swellable transparent surface layer and an inner portion of lower swellability than the surface layer, whereby the swellability of the surface layer decreases continuously from the exterior of the surface layer towards the inner portion to the swellability level of the inner portion.The swellability of the exterior of the surface layer is at the surface layer of up to 98% and the thickness of the surface layer is at utmost 100 .mu.m.The finally shaped lense is treated with an alkaline reacting solution of a salt, in which the lens does not swell and the lens is then freed of all soluble substances by washing.

Abstract: The invention pertains to a new design of contact lenses and to the method of their manufacturing. The contact lens comprising a carrier portion and a hydrophilic supporting portion mediating the contact of the lens with the eye surface, wherein both these parts are made from different materials, with the supporting portion being divided into two or more independent pieces protruding above the concave surface of the lens and lead from the lens circumference towards the lens center which is left free, with gaps being provided between individual pieces. The supporting part is made from a water-swelling synthetic crosslinked hydrogel which has, in the state of full swelling with physiological saline, a swelling capacity of about 40 to 95 percent, whereas the carrier optical portion is made from a transparent material having a modulus of elasticity at least twice that of the modulus of elasticity of the supporting portion. The supporting portion forms a gap of at least 0.

Abstract: The invention relates to a synthetic intraocular lens swellable in physiologic saline which is made from a polymer or a copolymer, at least one component of which is hydrophylic and the other one may be hydrophobic, crosslinked or non-crosslinked, whereas the content of swelling agent in it is below the equilibrium state whereby its glass-transition temperature T.sub.g is between -5.degree. C. and 45.degree. C. The lens is deformed above T.sub.g into a form suitable for surgical insertion, cooled below T.sub.g, and stored and surgically applied at the temperature below T.sub.g, and then relaxed in eye by post-swelling and heating. The lens may be incompletely swollen, instead in physiologic saline or water, in another physiologically harmless liquid, advantageously in glycerol.

Abstract: A method and apparatus for the polymerization cast molding of lenses from hydrophilic gels. A hydrophobic liquid which is essentially immiscible with a hydrophilic polymerization mixture is introduced into a mold having a hydrophobic surface, followed by dosing of the hydrophilic monomer mixture which is allowed to polymerize to form a drop which is pressed, while polymerizing, into the mold with a punch having a hydrophobic molding surface. The polymerizing monomer mixture is maintained under the pressure of the punch until the end of the polymerization. Any overflow of the two liquids is allowed to escape between the mold and the punch. The apparatus comprises a concave mold with an inner hydrophobic, rotation-symmetrical surface, and a punch with a hydrophobic molding surface which when placed in relationship to the mold has an overflow space formed between the mold and the punch.

Abstract: Hydrophilic silicones composite contain 10 to 150 wt. parts of a powdered hydrogel filler with particle size 10.sup.-6 to 10.sup.-1 mm on 100 parts by weight of crosslinked silicone polymer which forms a continuous matrix of the composite. The used hydrogel filler is formed made of physically or chemically crosslinked polymers or copolymers of polyol or dihydroxyether monomethacrylates, amides of methacrylic or acrylic acid or their N-monosubstituted and N,N-disubstituted derivatives, or a multiblock copolymer of acrylonitrile with acrylamide and/or acrylic acid. The hydrogel filler is mixed into the non-crosslinked silicone rubber, which is, after shaping, crosslinked by the known procedure of silicone rubber vulcanization at temperatures ranging from 15.degree. to 200.degree. C. These composites are substantially stronger, more plastic, and absorb more water than expected. Tensile strength and shape memory are improved. The composites are useful as biomaterials.