Classifications

• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/04—Optical elements characterised by the material of which they are made; Optical coatings for optical elements made of organic materials, e.g. plastics
  • G02B1/041—Lenses
  • G02B1/043—Contact lenses
• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
  • A61L27/00—Materials for grafts or prostheses or for coating grafts or prostheses
  • A61L27/14—Macromolecular materials
  • A61L27/18—Macromolecular materials obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F230/00—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal
  • C08F230/04—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing a metal
  • C08F230/08—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing a metal containing silicon
  • C08F230/085—Copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and containing phosphorus, selenium, tellurium or a metal containing a metal containing silicon the monomer being a polymerisable silane, e.g. (meth)acryloyloxy trialkoxy silanes or vinyl trialkoxysilanes

Definitions

• PROSTHESES PROSTHESES, CONTACT L ⁇ NSES, AND POLYMERS THEREFOR.
• This invention relates to polymers and to articles produced from such polymers including prostheses and contact lenses.
• siloxy-acrylate type monomers has been used to manufacture polymers for contact lenses. Such polymers however have frequently shown poor wettability and the prior art has employed numerous methods to improve the wettability of contact lenses fabricated from these polymers. Such treatments have included the deposition of hydrophilic polyelectrolyte complex coatings (e.g. U.K. Published Patent Application No.2012070A), the generation of hydrophilic (polar) groups on the lens surface by plasma glow discharge (e.g. U.S. Patent No.4143949), and the grafting of hydrophilic monomers to the lens surface.
• hydrophilic polyelectrolyte complex coatings e.g. U.K. Published Patent Application No.2012070A
• hydrophilic (polar) groups on the lens surface by plasma glow discharge e.g. U.S. Patent No.4143949
• a dimensionally stable, organosilicon polymer having pendant functional groups which groups are hydrolysable by means of biologically compatible aqueous liquids.
• a prosthesis or contact lens which is composed of an organosilicon polymer and which has a renewable wettable surface.
• a polymer which has hydrolysable functional groups, so that when a surface of the polymer is contacted by a biologically compatible aqueous liquid, e.g. water, the functional groups at the surface are hydrolysed thus to render the surface wettable.
• a biologically compatible aqueous liquid e.g. water
• Others of the functional groups which remain within the body of the polymer will not be hydrolysed so that, upon a fresh exposure of polymer (e.g. by cutting or polishing) to a said biologically compatible liquid further hydrolyzation will occur thus providing a renewable wettable surface.
• the functional groups may be provided in a siloxy monomer or prepolymer which is polymerised with any other suitable monomer or prepolymer to produce a polymer having desired characteristics, in such a way that the functional groups are not eliminated during the polymerization.
• the alkoxy groups are preferred, most particularly methoxy groups.
• a siloxy monomer or prepolymer (which may or may not contain hydrolysable functional groups of its own) may be copolymerized with one or more monomers or prepolymers which will provide the resultant polymer with the required hydrolysable functional groups.
• Suitable monomers are those including cyclic carboxylic anhydrides, amides esters and acetals as shown below:
• non-hydrolysable organo-silicon monomers which may be used with such hydrolysable monomers may be any of those used in prior art formulations. Examples of such monomers are disclosed, for example, in U.S. Patents Nos. 3808178,4120570 and 4216303, the contents of which are incorporated herein by reference.
• any hydrolysable silane containing poly merisable ethylenic bonds such as vinyl or acrylic may be employed to provide the hydrolysable functional groups.
• Preferred systems employ organo-silicon monomers or prepolymers of the following general formula I: wherein: each B, which may be the same as or different from each other, represents -OR 1 , R 1 being a C 1 -C 5 alkyl group or phenyl, t has a value of from 1 to 5 and R 2 is C 1 - C 5 alkyl, hydrogen or another organo siloxy group as defined in the general formula I.
• the compound is gamma methacry loxypropyl trimethoxy or triethoxy silane.
• Patents in the presence or absence of the aforesaid acrylic or methacrylic monomer, or in the presence or absence of one or more other organic monomers such as N-vinyl pyrrolidone or styrene.
• Preferred formulations incorporate gamma methacryloxypropyl trimethoxy silane, a said acrylic or methacrylic monomer, and a monomer or prepolymer of the following general formula II:
• n has a value of from 1 to 6
• n can be from 0 to an integer preferably less than or equal to 6
• a preferred compound of the general formula II is vinyl methyl siloxane prepolymer which may be considered to have the following formula
• Preferred monomer mixtures contain up to 30% by weight of the vinyl siloxane, up to 60% by weight of a monomer of general formula I and the balance being a said monomer derived from acrylic or methacrylic acid although, to increase the rigidity of the polymerized composition, a cross-linking agent may be incorporated in amounts which may be as high as 20 or 30% by weight of the total composition.
• the cross-linking agent may be selected from one or more of divinyl tetramethyl disiloxane ethylene glycol dimethacrylate allyl methacrylate and pentaerythritol tetraacrylate polyethylene glycol dimethacrylate triethylene glycol dimethacrylate tetraethylene glycol dimethacrylate divinyl benzene although any suitable cross-linking agent can be employed.
• compositions may be chemically polymerized or polymerized by electromagnetic irradiation, e.g. -irradiation, electron beam irradiation, etc.
• a free radical initiator or catalyst is generally added and the mixture subjected to controlled heat, preferably in a stepwise manner to ensure orderly and efficient incorporation of the monomers into the polymer.
• the temperatures selected are preferably from 40-90°C, the polymerization being effected preferably for not less than 3 days.
• Conventional free radical polymerization initiators may be employed such as azobis butyronitrile, benzoyl peroxide, tertiarybutyl peroxypivalate, chlorobenzyl peroxide,etc.
• the polymer can be cast into discs,rods or sheets for subsequent machining or directly into a lens shaped configuration. When polishing lenses prepared from such formulations it is generally advisable to use a water based polish.
• any suitable source may be employed, such as a Cobalt-60 source.
• the ⁇ -irradiation dosage is suitably from 2 to 5 Mega Pads.
• Methyl methacrylate 50% by weight The above constituents were weighed, thoroughly mixed in the proportions stated and then filtered and degassed at room temperature. Up to 1% by weight azobisbutyronitrile (AZBN) was added as a polymerization initiator and polymerization was effected at above ambient temperature with gentle stepwise heating to form a rod of polymer which was transparent, machinable, had good wettability and a water uptake after 3 days immersion of approximately 2.4% by weight.It had a renewable hydrolysable surface. The oxygen permeability was ascertained by a polarographic electrode technique to be 5.7DK x 10 -11 at 20° where DK has the following units:
• Example 2 By following the procedure of Example 1 a polymer was prepared from a mixture of 40 parts by weight gamma methacryloxypropyl trimethoxy silane 50 parts by weight methyl methacrylate, 10 parts by weight hydroxy ethyl methacrylate and 0.1 parts by weight AZBN.
• the resultant polymer was transparent, machinable and had a water uptake of 2.36%. It had a renewable hydrolysable surface.
• Example 2 By following the procedure of Example 1 a polymer was prepared from a mixture of 50 parts by weight gamma methacryloxypropyl trimethoxy silane, 30 parts by weight methyl methacrylate, 20 parts by weight diacetone acrylamide, 0.1 part by weight AZBN and 20 parts by weight of allyl methacrylate as cross-linker.
• the resultant polymer was transparent and had a renewable hydrolysable surface.
• Example 2 Following the procedure of Example 1 a polymer was prepared from a mixture of 17.5 parts by weight of vinyl methyl siloxane 54 parts by weight methyl methacrylate, 22.5 parts by weight of gamma methacryloxypropyl triethoxy silane, 0.1 part by weight AZBN and 10 parts by weight of allyl methacrylate as cross-linking agent.
• the resultant polymer was transparent with a refractive index of 1.45. It had a hardness of 80.46 (shore D) and a water uptake of 0.672%. It had a renewable hydrolysable surface, DK was 12.4 and the wetting angle was 62°.
• EXAMPLE 5 EXAMPLE 5
• a polymer was prepared exactly as in example 4 but using ethyl methacrylate instead of methyl methacrylate and gamma methacryloxypropyl trimethoxy siloxane in place of the triethoxy.
• the resultant polymer was transparent, machinable, had a water uptake of 0.92% and an oxygen permeability of 20.1 DK.
• the polymer had a renewable hydrolysable surface.
• a polymer was prepared exactly as in Example 5 but using 24 and 30 parts by weight respectively of ethyl and methyl methacrylate instead of ethyl methacrylate alone.
• the resultant polymer was transparent,machinable had a water uptake of 1.1% and a DK of 13.2.
• the polymer had a renewable hydrolysable surface.
• a polymer was prepared as in Example 1 using 7 parts by weight vinyl methyl siloxane, 18 parts of gamma methacryloxypropyl trimethoxy silane, 15 parts by weight hexyl methacrylate, 30 parts by weight methyl methacrylate, 10 parts by weight allyl methacrylate and 0.1 part by weight AZBN.
• the resultant polymer was transparent, machinable and had a water uptake of 1.34%.
• the polymer had a renewal hydroly sable surface. DK was 8.7 and the wetting angle was 70°.
• A. polymer was prepared following the procedures of Example 1 from a mixture of 16.5 parts by weight vinyl methyl siloxane, 41 parts by weight methyl methacrylate, 22.5 parts by weight gamma methacryloxypropyl trimethoxy silane, 0.1 part by weight AZBN and 20 parts by weight of ethyleneglycol dimethacrylate as a cross-linking agent.
• the resultant polymer was translucent and machinable, with a water uptake of 1.3% and a DK of 12.4.
• the polymer had a renewable hydrolysable surface.
• a polymer was prepared following the procedure of Example 1 but employing a mixture of 28 parts by weight of vinyl methyl siloxane, 48 parts by weight of methyl methacrylate, 18.9 parts by weight of gamma methacryloxypropyl trimethoxy silane
• the resultant polymer was transparent, machinable had a water uptake of 0.21% and a DK of 16.9.
• the polymer had a renewable hydrolysable surface (wetting angle 68°).
• a polymer was prepared according to the procedure of Example 1 but employing a mixture of 17.5 parts by weight vinyl methyl siloxane, 55 parts by weight methyl methacrylate, 22.5 parts by weight gamma methacryloxypropyl trimethoxy silane, 0.1 part by weight AZBN and 5-0 parts by weight of divinyl tetramethyl disiloxane as a cross-linking agent.
• the resultant polymer was transparent and machinable and had a water uptake of 1.49%.
• the polymer had a renewable hydrolysable surface.
• a polymer was prepared by ⁇ -irradiating a mixture containing 15 parts by weight of vinyl methyl siloxane, 60 parts by weight methyl methacrylate and 25 parts by weight of gamma methacryloxypropyl trimethoxy silane.
• the resultant polymer was transparent, machinable, had a water uptake of 0.5% and a DK of 5.11.
• the wetting angle was 62.5°.
• the present invention provides a polymer whose characteristics such as transparency, hardness (or softness), wettability and oxygen permeability can be tailored to meet a particular requirement.
• the present invention is capable of providing polymers suitable for contact lenses which can be eye-compatible, relatively bacter ilgically inert, scratch-resistant, machinable and polishable, hard or soft, transparent or opaque, and wettable.
• Preferred polymers are hard and transparent with low wetting angles and high oxygen permeability.
• the monomer of general formula I contributes to monomer solution/polymerization compatibility, to oxygen permeability and, importantly, to lens wettability (and hence to wearer comfort), due to the presence of the hydrolysable groups B, whilst the acrylic or methacrylic acid monomer, if present, contributes to the optical and cutting qualities.
• the compound of general formula II if present, contributes to oxygen permeability.
• colouring matter can be introduced into the monomer mixtures in order that tinted contact lenses can be produced.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Physics & Mathematics (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Epidemiology (AREA)
• General Physics & Mathematics (AREA)
• Optics & Photonics (AREA)
• Dermatology (AREA)
• Polymers & Plastics (AREA)
• Transplantation (AREA)
• Organic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Eyeglasses (AREA)
• Addition Polymer Or Copolymer, Post-Treatments, Or Chemical Modifications (AREA)
• Materials For Medical Uses (AREA)

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• 1983
  • 1983-08-29 IT IT22672/83A patent/IT1194382B/it active
  • 1983-08-30 EP EP83902999A patent/EP0116638A1/de not_active Withdrawn
  • 1983-08-30 WO PCT/GB1983/000213 patent/WO1984000969A1/en not_active Application Discontinuation
  • 1983-08-30 AU AU19443/83A patent/AU1944383A/en not_active Abandoned
• 1984
  • 1984-04-27 DK DK2141/84A patent/DK214184D0/da unknown

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