Modified silicone rubber and its use as a material for optical lenses and optical lenses made from this material

Claim 2

Silicone rubber having hydrophilic properties and having main chains of the partial formula --OCONH--R.sup.1 --NHCO--OCH.sub.2 C(CH.sub.3).sub.2 CHOHCONH(CH.sub.2).sub.3 --O--CONH--R.sup.1 --NHCO--O--R.sup.2 -- in which R 1 is --(CH 2 ) w --, ##STR14## w being an integer from 2 to 16, and R 2 is ##STR15## where n is 3, 4 or 5, and with said main chains being crosslinked through methyl groups.

Claim 3

An optical lens wherein the whole of the lens body comprises a modified silicone rubber according to claim 1.

Claim 4

An optical lens according to claim 2 which is a contact lens.

Claim 5

An optical lens according to claim 2 which is an intraocular lens.

Claim 6

An optical lens wherein the surface of the lens body comprises a modified silicone rubber according to claim 1.

Claim 7

An optical lens according to claim 5 which is a contact lens.

Claim 8

An optical lens according to claim 5 which is an intraocular lens.

Claim 9

A process for the synthesis of a modified silicone rubber with hydrophilic properties which comprises (a) reacting a diisocyanate with pantothenol in a 2:1 molar ratio to form an adduct having terminal isocyanate groups, (b) then reacting the adduct product of step (a) with a dimethylsiloxane having hydroxyalkyl groups to obtain a polymer having dimethylsiloxane and urethane units, and (c) then causing said polymer to crosslink through said methyl groups.

Claim 10

A process for the synthesis of a modified silicone rubber with hydrophilic properties which comprises (a) reacting a diisocyanate with pantothenol in a 2:1 molar ratio to form an adduct having terminal isocyanate groups, (b) then reacting the adduct product of step (a) with a dimethylsiloxane having hydroxyalkyl groups to obtain a polymer having dimethylsiloxane and urethane units, and (c) then causing said polymer to crosslink through said methyl groups.

Claim 11

A process according to claim 8 in which the dimethylsiloxane is 1,3-bis(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane, 1-(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxane, 1,3-bis(6,7-dihydroxy-4-oxaheptyl)-1,1,3,3-tetramethyldisiloxane, 3,5-bis(3-hydroxypropyl)-1,1,1,3,5,7,7,7-octamethyltetrasiloxane, 1-(6,7-dihydroxy-4-oxaheptyl)-1,1,3,3-tetramethyldisiloxane, 2,4,6,8-tetrakis(3-hydroxypropyl)-2,4,6,8-tetramethylcyclotetrasiloxane, methylene-bis(1,4-cyclohexylene(carbamic acid)-3-[3-(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxanyl]-propyl ester, or hexamethylene-1,6-bis(carbamic acid)-3-[3-(3-hydroxypropyl)-1,1,3,3-tetramethyldisiloxanyl]-propyl ester.

Claim 12

A process according to claim 8 wherein rubber-forming initiators are used as crosslinking agents.

Claim 13

A process according to claim 10 in which the crosslinking agent is a peroxide.

Claim 14

A process according to claim 8 wherein the molar ratio of dimethylsiloxane to diisocyanate is 1:2.