MXPA97004917A - Vinyl telomeros nco-termina - Google Patents

Abstract

The present invention relates to vinyl telomers of the formula I: O = C = N-PI * _ (_ A-) p-Ra where PI * represents a bivalent radical of a photoinitiator, A represents a radical 1,2- substituted divalent ethylene, which is derived from a copolymerizable vinyl monomer by replacing the double bond of the vinyl with a single bond, each Ra, independently of each other, represents a univalent group, which is suitable to serve as a chain switch of a polymerization , and p represents an integer from 3 to 5

Description

NCO-TERMINAL VINYL TELEMERS The invention relates to novel NCO-terminal vinyl sheets, which are particularly suitable for surface modification and as a coating material, but also for the preparation of polymerizable compounds or segmented copolymers, which can be converted into polymers, or, in molded bodies; in addition to molded bodies containing this type of polymers, also to the use of polymers for the manufacture of molded bodies and the process for obtaining the polymers and molded bodies. Preferred moldings are ophthalmic lenses, particularly contact lenses. Vinyl telomeres are characterized, among other things, with respect to the known vinyl telomers, because they have a narrower distribution of the molecular weight of the respective chain lengths formed, of or of the vinyl monomers used, and because they are mono -functionalized with the isocyanate group particularly reactive. The OCN-terminal vinyl telomers according to the invention are compounds of the formula I, 0 = C = N-PI * _ (_ A-) p-Ra (I) where Pl * represents a bivalent radical of a photoinitiator, A represents a substituted bivalent 1,2-ethylene radical, which is derived from a monomer of copolymerizable vinyl replacing the vinyl double bond by a single bond, each Ra, independently of each other, represents a univalent group, which is suitable to serve as a chain switch of a polymerization, and p represents an integer from 3 to 500. The group - (A) p- in formula I, or the vinyl monomers used for their preparation, preferably do not contain any H-active group. The vinyl telomeres of the formula I, according to the invention, can be obtained by reacting a photoinitiator of the formula B, 0CN-PI * -Raa (B) wherein Pl * is defined as indicated above and Raa represents the part of a photoinitiator which, in a dissociation thereof, forms the less reactive radical, with a vinyl monomer in a manner known per se, which is incorporated as a component "A" in the vinyl telomere, where A is defined as indicated above. The chain interruption takes place, for example, by the less reactive radical of the Raa photoinitiator of formula B or by other suitable chain terminators, which are present in the reaction mixture under the reaction conditions, such as for example H radicals or OH radicals or radicals formed by solvents. The variable Ra is preferably the Raa component of the photoinitiator of formula B. The polymerizable compounds according to the invention are compounds of formula C, O Mono-Rx-C-NH-P -'- i-A-J-F-a ^ wherein mono represents a univalent radical of a vinyl monomer, of which the Rx-H group is separated, Rx, independently of each other, represents a bond, -O-, - NRN- or -S-, wherein RN represents hydrogen or lower alkyl, Pl * represents a bivalent radical of a photoinitiator, A represents a bivalent, substituted 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the vinyl double bond with a single bond, each Ra , independently of each other, represents a univalent group, which is suitable to serve as a chain switch of a polymerization, and p represents an integer from 3 to 500. The meaning of "link" for Rx is only relevant for the case where an OH group is present in the univalent radical of a vinyl monomer as a component of a COOH group. A COOH group reacts with an isocyanate group under dissociation of C02 and forms a "-CO-NH-" bond. Only in this case does Rx mean a bond in the product of the reaction, but not in a starting product that contains the group "Rx-H". The polymerizable compounds of the formula C, according to the invention, can be obtained by reacting a vinyl telomer of the formula I, as defined above, in a manner known per se, with a vinyl monomer containing at least one Rx group -H, where Rx is defined as indicated above, but is different from a link. The segmented copolymers according to the invention are non-crosslinked but, optionally, crosslinkable copolymers of the formula D, (D) wherein macro represents a m-valent radical of a macromer, of which the number of m groups Rx-H is separated, Rx, independently of each other, represents a bond, -O-, - NRN- or -S-, wherein RN represents hydrogen or lower alkyl, Pl * represents a bivalent radical of a photoinitiator, A represents a substituted bivalent 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the vinyl double bond with a single bond, each Ra, independently of each other, represents a univalent group, which is suitable to serve as a chain switch for a polymerization, p represents an integer from 3 to 500, and m represents an integer from 1 to 100. The meaning of "link" for Rx is only relevant for the case where an OH group is present in the macromer as a component of a COOH group. A COOH group reacts with an isocyanate group under CO cleavage and forms a "-CO-NH-" bond. Only in this case does Rx mean a bond in the product of the reaction, but not in a match product containing the group "Rx-H". By a segmented copolymer are meant block copolymers, graft copolymers according to the invention, particularly comb copolymers, or star copolymers.

The segmented copolymers of the formula D, according to the invention, can be obtained by reacting in a manner known per se a macromer of the formula A: Macro- (RxH) m (A) where Macro, Rx and m are defined as indicated above, but Rx is distinct from a bond, with a vinyl telomer of formula I, 0 = C = N-PI * _ (_ A-) p-Ra (I) where Pl *, A, Ra and p are defined as indicated above. The macromer of the formula A suitable according to the invention has a number m of -RxH groups, which are hydroxyl groups (also those which are a component of a carboxyl group -COOH), amino groups or lower alkylamino groups (also those which are component of an amide group -CONRN) or mercapto groups. These groups are coreactive with the isocyanate group of the photoinitiator of formula B. The foregoing is analogously valid for vinyl monomers which control the "mono" radical in a compound of formula C.

The index p preferably represents a number from 5 to 200, particularly a number from 10 to 100. The index m preferably represents a number from 2 to 15, particularly a number from 2 to 5. The polymers according to the invention are products of polymerization of a polymerization capable mixture containing the following components: a) a compound capable of polymerization of formula C as defined above, b) optionally a copolymerizable vinyl monomer, c) a copolymerizable crosslinker; or polymerization products of a polymerization capable mixture containing the following components: aa) a compound capable of polymerization of the formula D as defined above, wherein a reactive group, bb, is contained in the component - (A) p- ) optionally a copolymerizable vinyl monomer, ce) a crosslinker which is coreactive with the reactive group in the component - (A) p- of the compound of formula D. In the abovementioned polymerization-capable mixtures, a compound of formula C or D, if a copolymerizable vinyl monomer is used, preferably in an amount of 10 to 90% by weight, particularly 20 to 80% by weight; a copolymerizable vinyl monomer, preferably in an amount of 10 to 90% by weight, particularly of 20 to 80% by weight, is used, that is to say if present, these weight percentage indications referring to the amounts of components a) and b), or, aa) and bb) relatively to each other. A crosslinker c) or ce) is preferably used in an amount of up to 25% by weight, particularly in an amount of up to 12.5% by weight, based on the sum of components a) and b), or, aa) and bb). In the case of a c) copolymerizable crosslinker as mentioned in the previous paragraphIt is a typical oligovinyl crosslinker, as is known from the prior art. In the case of a crosslinker ce) as mentioned in the previous paragraph, it is an oligofunctional compound, which is coreactive with the reactive groups contained in the - (A) p- part. By a reactive group in the part - (A) p- is meant basically any reactive group which is inert, or of little reaction with respect to an isocyanate group, for example the isocyanate group or the epoxy group. A group of an oligofunctional compound coreactive with the above is, for example, the amino group or the hydroxyl group. Suitable oligofunctional compounds are, for example, diamines, diols or aminoalcohols, for example. Other examples are known to the person skilled in the art. The groups, of which, according to the meaning of the index m, are linked 1 to 100 to the macromer of the formula A, are either terminals or slopes or terminals and slopes. In a preferred embodiment, the macromer of formula A has two terminal RXH groups. A copolymer of the segmented formula D, according to the invention, formed from the latter, or else, a block copolymer of the formula D is also particularly preferred and is referred to in this invention as a triblock copolymer: the central block is formed basically by the macromer, to which two blocks of radical photoinitiator- (A) p-Ra are linked. In another preferred embodiment, the macromer of formula A presents only outstanding RXH groups. A copolymer of the segmented formula D, according to the invention, formed from the latter, or else, a graft copolymer of the formula D is also preferred and is referred to in this invention as a comb copolymer: the back or the rib of the comb is formed by the macromer, to which several photoinitiators are linked in a pending manner, the comb teeth or teeth are basically formed by bivalent radicals A, which are linked through the radical of the photoinitiator. In another preferred embodiment, a cyclic macromer of formula A exhibits pending RXH groups. A copolymer of the segmented formula D, according to the invention, formed from the latter, or else, a graft copolymer of the formula D, is also preferred and is referred to in this invention as a star copolymer: the central point of the star is formed by the macromer, to which several photoinitiators are linked; the rays of the star are basically formed by bivalent radicals A, which are linked through the radical of the photoinitiator. It is significant that the vinyl telomers according to the invention, the segmented copolymers or the polymerizable compounds obtainable therefrom and the crosslinked polymers obtained therefrom, differ in their characteristics surprisingly from the usual components. This is valid on the one hand because the chain length of the vinyl monomers (see - (A) p- in formula I) can be controlled to a large extent according to the invention, so that, for example, it can be achieved a comparatively narrow molecular weight distribution. In addition, the vinyl telomers of the formula I are surprisingly free, or at least substantially free of the homopolymers of the vinyl monomer respectively used, as well as of bis-OCN-terminated telomers and polymers, which, in other cases, are normally formed by secondary reactions. These advantageous characteristics, in the course of obtaining the polymerizable compounds of the formula C, of the segmented copolymers of the formula D and of the polymers mentioned, according to the invention, are transferred thereto. Furthermore, the vinyl telomeres according to the invention and the products thereof obtainable, as, for example, described above, present the advantages that can be obtained through a simple and rapid synthesis by UV polymerization, that, in obtaining it, there are few secondary reactions, of which the products are colorless in any case and can also be obtained starting from labile vinyl monomers. Practically no unfinished vinyl telomers are formed with the isocyanate group or consequent corresponding products by an eventual initiation of a homopolymerization of the vinyl monomer by the second radical fragment of the photoinitiator. Instead, the second, less reactive radical apparently shows during the photopolymerization a certain cage effect and acts as an efficient chain switch instead of initiating a homopolymerization of the vinyl monomer. Neither side reactions were observed leading to telomeres or a,? - difunctional polymers. The copolymers of the formula D according to the invention or the polymerizable compounds of the formula C can be converted into, or processed in, controlled products. It should be noted in particular the fact that the non-crosslinked compounds of the formula C or D can be incorporated in a simple manner into crosslinked polymers, for example, by carrying out the conversion of a compound of the formula C or D in the presence of a crosslinking agent. In addition to, or alternatively, crosslinking of this type, the compounds according to the invention of the formula C or D can be modified if, in the part - (A) p-, according to formula I, they have reactive groups. In the case of this type of reactive groups, it may be, for example, isocyanate or epoxy groups, which are derived from a vinyl isocyanate or a vinyl epoxide compound, such as, for example, 2-isocyanatoethyl methacrylate or glycidyl (meth) ) acrylate, which is further reacted with a hydroxy-lower alkyl- (meth) acrylate, for example 2-hydroxyethylmethacrylate or 3-hydroxypropylmethacrylate. The dc double bonds of a hydroxy-lower alkyl (meth) acrylate, which were incorporated in the manner thus described, allow crosslinking to obtain a polymer according to the invention and / or copolymerization with another vinyl monomer or monomer of divinyl Above and then, a "(meth) acrylate" formulation is used to abbreviate "methacrylate or acrylate". All the aforementioned characteristics make the polymers according to the invention suitable for a large number of applications as molded bodies of various types, namely as biomedical materials, for example, implants, ophthalmic lenses, particularly synthetic cornea, intraocular lenses or, very particularly preferred, contact lenses, or as medical instruments, apparatuses, membranes, drug delivery systems, or as coatings on materials inorganic or organic In addition, the non-crosslinked vinyl telomers of the formula I are suitable not only as starting materials for the polymers according to the invention, but also excellently for the production of modified surfaces, such as biomedical materials, ophthalmic lenses, particularly contact lenses, or implants, as well as for coatings on inorganic or organic materials. For this purpose, only the transformation of the highly reactive isocyanate group of the vinyl telomers of the formula I with H-active groups of the respective surface is required. With "A" hydrophilic components, block, comb or star amphiphilic polymers are obtained which have active surface characteristics and, for example, are suitable as emulsifiers. Therefore, the invention relates, inter alia, to molded bodies, particularly contact lenses of the segmented copolymers, polymerizable compounds or polymers mentioned. The invention also relates to the manufacture of molded bodies, particularly contact lenses, of the segmented copolymers, polymerizable compounds or polymers mentioned, as well as the use of the segmented copolymers, the polymerizable compounds or the aforementioned polymers for the manufacture of molded bodies, particularly of contact lenses, as well as the use of the vinyl telomers according to the invention for the manufacture of surfaces, or modified coatings, particularly contact lens surfaces. In the case of the macromers of the formula A, it is preferably oligomers or polymers with an average molecular weight of 300 to 10,000 Dalton and preferably contains at least 3, more preferably 3 to 50 and particularly preferred 5 to 20 units. structural The passage between oligomers and polymers is, as it is known, fluid and can not be precisely limited. The polymers may contain 50 to 10'000, more preferably 50 to 5'000 structural units and have an average molecular weight of 10'000 to 2'000'000, preferably 10'000 to 500'000. The oligomers and polymers can also contain up to 95 mol%, more preferably 5 to 90 mol% of comonomeric structural units without H-active groups (here, this term has the same meaning as "R? H groups", defined as indicated above, with the proviso that RX is, in this case, different from a link), referred to the polymer. In the case of oligomers and polymers with H-active groups, it can be natural or synthetic oligomers or polymers. Oligomers and natural polymers are, for example, oligo- and polysaccharides or their derivatives, proteins, glycoproteins, enzymes and growth factors. Some examples are peptides, cyclodextrin, starch, hyaluronic acid, deacetylated hyaluronic acid, chitosan, trehalose, cellobiose, maltotriose, maltohexaose, chytohexaose, agarose, chitin 50, amylose, glucans, heparin, xylan, pectin, galactane, poly-galactosamine, glycosaminoglycans, dextran, dextran amine, cellulose, hydroxyalkylcelluloses, carboxyalkylcelluloses, heparin, fucoidan, chondroitin sulfate, polysaccharides sulfates, mucopolysaccharides, gelatin, zein, casein, seidenfibroin, collagen, albumin, globulin, bilirubin, ovalbumin, keratin, fibronectin and vitronectin, pepsin, trypsin and lysosim. The synthetic oligomers and polymers can be substances containing the groups -COOH, -OH, -NH2 or -NHRN, wherein RN means lower alkyl, preferably alkyl having 1 to 6 carbon atoms. It can be treated, for example, of saponified polymers of esters or vinyl ethers (polyvinylalcohol), hydroxylated polydiolefins, such as polybutadiene, polyisoprene or chloroprene; polyacrylic acid and polymethacrylic acid as well as polyacrylates, polymethacrylates, polyacrylamides or polymethacrylamides with hydroxyalkyl or aminoalkyl radicals in the ester group or the amide group; polysiloxanes with hydroxyalkyl or aminoalkyl groups; polyether of epoxies or glycidyl compounds and diols; polyvinylphenols or copolymers of vinylphenol and olefinic comonomers; as well as copolymers of at least one monomer of the group vinylalcohol, vinylpyrrolidone, acrylic acid, methacrylic acid, anhydride of (meth) acrylic acid or acrylates containing hydroxyalkyl or aminoalkyl, methacrylates, or acrylamide or methacrylamide, or hydroxylated diolefins with ethylenically unsaturated comonomers , such as, for example, acrylonitrile, olefins, diolefins, vinyl chloride, vinylidene chloride, vinyl fluoride, vinylidene fluoride, styrene, α-methylstyrene, ethers and vinyl esters; or of polyoxaalklycenes with terminal OH or aminoalkyloxy groups. Preferred oligomers or polymers are, for example, cyclodextrins with in total 6 to 8 glucose structural units which form a ring or hydroxyalkyl or aminoalkyl derivatives or derivatives substituted with glucose or maltose, of which at least one structural unit corresponds to the formula (V), wherein R7, R8 and R9, independently of one another, represent alkyl having 1 to 4 carbon atoms, particularly methyl, acyl with 2 to 6 carbon atoms, particularly acetyl, hydroxyalkyl with 1 to 4 carbon atoms, particularly hydroxymethyl or -hydroxy-et-1-yl, aminoalkyl with 2 to 10 carbon atoms and particularly aminoalkyl with 2 to 4 carbon atoms, for example 2-amino-et-1-yl or 3-aminoprop-1-yl or 4- aminobut-l-yl, Xx means -O- or -NR1B-, wherein per unit of cyclodextrin in total 1 to 10 and preferably 1 to 6 X? they can mean -NRIB- and the remaining X¿ represent -O-, wherein R1B means hydrogen or lower alkyl. Other preferred oligomers and polymers are, for example, oligo- or polysiloxanes with OH or NH2 groups on the alkyl, alkoxyalkyl or aminoalkylene side groups or chains. It can be statistical oligomers of block or block polymers. Preferred oligomers and polymers are those containing a) 5 to 100 mol% of structural elements of the formula (VII) (b) 95 to 0 mol% of structural elements of the formula (VIII) referred to the oligomer or polymer, wherein R n means alkyl having from 1 to 4 carbon atoms, optionally partially or wholly substituted by F, lower alkenyl, cyano-lower alkyl or aryl, preferably methyl, ethyl, vinyl, allyl, cyanpropyl or trifluoromethyl, R12 means alkylene with 2 to 6 carbon atoms, preferably 1,3-propylene, - (CH2) z- (0-CH2-CHCH3-) z-, - (CH2) z- (0-CH2 -CH2) zo - (CH2) Z-NH- (CH2) Z-NH-, preferably - (CH2) 3- (0-CH2-CHCH3-) 2 or - (CH2) 3 ~ NH- (CH2) 2 -NH, where z is an integer from 2 to 4, R14 has the meaning of R ^ or represents -R12-X! -H or -R? 2- 1 -R15-H, x? represents -O- or -NH-, R13 represents a radical RxH and R15 represents a direct bond or a group -C (0) - (CH0H) r -CH2-0, where r represents 0 or an integer of 1 to 4. Oligomers or preferred polymers are also those of the formula (X) wherein R n means alkyl having 1 to 4 carbon atoms, optionally partially or fully substituted with F, vinyl, allyl or phenyl, preferably methyl, R 12 means alkylene with 2 to 6 carbon atoms, preferably 1,3 -propylene, Rj_ has the meaning of Rn or represents -R? - Xi-H or -R12-X1-R15-H, Xi represents -0- or -NH-, s represents an integer from 1 to 1 OOO and, preferably, from 1 to 150, and R13 represents a radical RXH and R15 represents a direct bond or a group -C ('O) - (CHOH) r-CH2-0, where r represents 0 or an integer from 1 to 4. X ^ represents here, preferably, -NH-. Other preferred oligomers and polymers are those based on oligo- and polyvinylalcohol. It can be homopolymers with structural units -CHCH (OH) or copolymers with other mono or bivalent olefin structural units. More preferred are those oligomers and polymers containing a) 5 to 100 mol% of structural units of the formula (XI) b) 95 to 0 mol% of structural units of the formula (XII) wherein R16 represents a radical RXH, R17 represents H, alkyl having 1 to 6 carbon atoms, -COOR20 or -COO ~, R18 represents H, F, Cl, CN or alkyl having 1 to 6 carbon atoms, and R19 represents H, OH, R? 0-H, F, Cl, CN, R20-O-, alkyl with 1 to 12 carbon atoms, -C00-, -COOR2? / -0C0-R2o / methylphenyl or phenyl, wherein Rio represents a direct bond, - (alkylene with 1 to 4 carbon atoms -O) - or - (alkylene with 2 to 10 carbon atoms -NH) - and R2o represents alkyl with 1 to 18 carbon atoms, cycloalkyl with 5 to 7 carbon atoms, (C 1-12 alkyl) -cycloalkyl with 5 to 7 carbon atoms, phenyl, (C 1-12 alkyl) phenyl, benzyl or (C 1-12 alkyl) I'm talking R 17 preferably represents H. If R 17 is alkyl, it is preferably methyl or ethyl. If R17 means -COOR 2 O R 20 preferably represents alkyl with 1 to 12 carbon atoms, particularly alkyl having 1 to 6 carbon atoms. If Ri8 means alkyl, it is preferably alkyl having 1 to 4 carbon atoms, for example methyl, ethyl, n-propyl or n-butyl. R18 preferably represents H, Cl or alkyl with 1 to 4 carbon atoms. If R9 means the group Ro ~ 0, R2o preferably represents alkyl with 1 to 12 carbon atoms, particularly with 1 to 6 carbon atoms. If R9 represents alkyl, it preferably contains 1 to 6, particularly 1 to 4, carbon atoms. If R? G means the group -COOR2Q, R2O preferably represents alkyl having 1 to 12 carbon atoms, particularly alkyl having 1 to 6 carbon atoms, cyclopentyl or cyclohexyl. If R19 means the group -OCO-R2? / R2? it preferably represents alkyl with 1 to 12 carbon atoms, particularly alkyl with 1 to 6 carbon atoms, phenyl or benzyl. In a preferred embodiment, R 17 means H, R 18 H, F, Cl, methyl or ethyl, and R 19 H, OH, F, Cl, CN, alkyl having 1 to 4 carbon atoms, alkoxy with 1 to 6 carbon atoms, hydroxyalkoxy with 1 to 6 carbon atoms, -COO-alkyl with 1 to 6 carbon atoms, -OOC-alkyl with 1 to 6 carbon atoms or phenyl. Particularly preferred are those oligomers and polymers in which R 17 is H, R 8 H or methyl and R 19 H, OH, CN, methyl, OCH 3, C) (CH 2) t 0 -COOCH 3, and t represents an integer from 2 to 6. Another preferred group of oligomers and polymers are oligo- or polyacrylates or -methacrylates, or -acrylamides or -methacrylamides partially or wholly hydroxyalkylated. They may contain, for example, 5 to 100% by mol of structural units of the formula (XIII) and 95 to 0 mol% of structural units of the formula (XIV) wherein R21 signifies H or methyl, X2 and X3, independently of each other, denote -O- or -NH-, R22 represents - (CH2) C and c is an integer from 2 to 12, preferably from 2 to 6, R23 means a radical of the formula RXH, R17 and R18 have the meaning indicated above, and R24 has the same meaning as R19 or means -C (O) X2R22X3H. For R17, R18 and R19 the preferences mentioned above are valid. For X2 and X3 the preferences indicated above are valid. Other preferred oligomers and polymers are those of polyalkylene oxides. It can be, for example, those of the formula (XV) with the same or different recurrent structural units ~ [CHCH (R26) -O] -, R25- [(CH2CH-O-) "] v- R27- 4-R2S (XV), R26 wherein R25 represents the group R28-X or the radical of an alcohol or polyol with 20 carbon atoms, the valence of this radical being 1 av, R2β is H, alkyl having 8 carbon atoms, preferably alkyl with 1 to 4 carbon atoms and particularly preferred methyl, R2, together with X4, represents a direct bond or R7 represents alkylene with 2 to 6 carbon atoms, preferably alkylene with 3 to 6 carbon atoms and particularly preferred 1.3 -propylene, X4 represents -0- or -NH-, R28 means a radical of the formula RXH, u is a number from 3 to 10000, preferably from 5 to 5000, particularly preferred from 5 to 100, and especially Preferred 5 to 100, and v represents an integer from 1 to 6, preferably 4. R25 can be a tetravalent univalent radical of an alcohol or polyol. If R25 is the radical of an alcohol, R25 preferably means alkyl with 3 to 20 carbon atoms, straight or branched, or alkenyl with 3 to 20 carbon atoms, straight or branched, cycloalkyl with 3 to 8 and particularly with 5 to 6 carbon atoms, -CH 2 - (cycloalkyl with 5 to 6 carbon atoms), aryl with 6 to 10 carbon atoms and, particularly, phenyl and naphthyl, aralkyl with 7 to 16 carbon atoms and, particularly, benzyl and -phenilet-2-yl. The cyclic or aromatic radicals can be substituted with alkyl having 1 to 18 carbon atoms or alkoxy with 1 to 18 carbon atoms.

If R25 is the radical of a diol, R25 preferably means alkylene or alkenylene with 3 to 20 carbon atoms, straight or branched, and more preferably alkylene with 3 to 12 carbon atoms, cycloalkylene with 3 to 8 and particularly 5 to 6 carbon atoms, -CH 2 - (cycloalkyl with 5 to 6 carbon atoms) -, -CH 2 - (cycloalkyl with 5 to 6 carbon atoms) -CH 2 -, aralkylene with 7 to 16 carbon atoms and, particularly, benzylene , -CH2- (aryl with 6 to 10 carbon atoms) -CH2- and, particularly xylylene. The cyclic or aromatic radicals can be substituted with alkyl having 1 to 12 carbon atoms or alkoxy with 1 to 12 carbon atoms. If R 5 is a trivalent radical, this is derived from aliphatic or aromatic triols, R 25 is preferably a trivalent aliphatic radical with 3 to 12 carbon atoms which is derived in particular from triols with, preferably, primary hydroxyl groups. Particularly preferably, R25 is -CH2 (CH-) CH2-, HC (CH2-) 3 or CH3C (CH2- If R25 is a tetravalent radical, this is preferably derived from aliphatic tetroles, R25 is in this case preferably C (CH 2 -) 4 R 25 preferably represents a radical, which is derived from Jeffamine (Texaco), a pluriol, a poloxamer (BASF) or poly (tetramethylene oxide).

Particularly preferred are homooligomers and block oligomers and homopolymers and block polymers with structural units of the formulas - [CH CH2-0] - or - [CH2CH (CH3) -0] -. Also suitable are fluorinated polyethers corresponding to formula (XVI) - [(CF2CF-O-) u] v-R2r_? 4 - R28 (XVI) R wherein R27, R28, X4, u and v have the meaning indicated above, R5 has the aforementioned meaning or means the univalent radical of a fluorinated alcohol partially or perfluorinated with 1 to 20, preferably 1 to 12 and particularly preferred 1 to 6 carbon atoms, or the bivalent radical of a partially fluorinated or perfluorinated diol with 2 to 6, preferably 2 to 4 and particularly preferably 2 or 3 carbon atoms, and Rd means F or perfluoroalkyl with 1 to 12, preferably 1 to 6 and particularly preferably 1 to 4 carbon atoms. R is particularly preferably -CF3. Other suitable oligomers and polymers are, for example, polyamines, such as, for example, polyvinylane or polyethyleneimines. Poly-e-lysine is also suitable. As a photoinitiator of formula B, basically any photoinitiator containing an isocyanate group is suitable. This type of photoinitiators have already been described, for example, in EP-A-632329. Suitable photoinitiators typically present the structural element (meaning the formulation "OH / NR'R" "that the doubtable carbon atom carries either an OH group or a group NR'R", where R 'and R ", independently of each other, mean linear or branched lower alkyl , which may be substituted by alkoxy with 1 to 4 carbon atoms, aryl lower alkyl or lower alkenyl, or R 1 and R "signify together - (CH 2) Z - Y n - (CH 2) 2 -, where Y n is a direct bond, -O-, -S- or -NR1B- and RIB is H or lower alkyl and z represents an integer from 2 to 4), which with the appropriate excitation forms two radicals, dissociating the bond between the benzoyl-carbon and the sp -carbon. Normally, the benzoyl radical is the most reactive, which in any case initiates a polymerization. The variable Pl * of formula B therefore corresponds, preferably, to a benzoyl radical of this type. This benzoyl radical, as is known from the prior art, is substituted and additionally contains an isocyanate group according to the invention. From the above it follows that the sp-carbon radical is the least reactive, which usually does not contribute to initiate a polymerization. Instead, it reacts preferably as a chain switch. The variable Raa of formula B therefore corresponds, preferably, to a sp-carbon radical of this type. Particularly preferred photoinitiators according to the invention are described below. The functional photoinitiators of the formula B, to be used according to the invention, are preferably compounds of the formulas lia or Ilb where Y means O, NH or NR? A; And it means O; Y2 means -0-, -0- (0) C-, -C (0) -0- or -0-C (0) -0-; the n, independently of each other, represent 0 or 1; R is H, alkyl with 1 to 12 carbon atoms, alkoxy with 1 to 12 carbon atoms or al? [Uils with 1 to 12 carbon atoms-NH-; Ri and R, independently of each other, represent H, linear or branched alkyl with 1 to 8 carbon atoms, hydroxyalkyl with 1 to 8 carbon atoms or aryl with 6 to 10 carbon atoms, or two groups R? - (Y ?) n ~ mean - (CH) X-, or the groups R? - (Y?) n- R2"(??) n ~ together form a radical of the formula \ / -CH2 R3 represents a direct bond or linear or branched alkylene with 1 to 8 carbon atoms, which is unsubstituted or substituted with -OH and / or, if appropriate, is interrupted with one or more groups -O-, -OC (O ) - or -oC (?) - O-; 4 represents alkylated branched with 3 to 18 carbon atoms, arylene with 6 to 10 carbon atoms, unsubstituted or substituted with alkyl with 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, or aralkylene with 7 to 18 carbon atoms, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, cycloalkylene with 3 to 8 carbon atoms, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, cycloalkylene with 3 to 8 carbon atoms-CyHy- unsubstituted or substituted with alkyl with 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, or -CyH2y- (cycloalkylene with 3 to 8 carbon atoms) -CyH2y-, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms; R5 independently has the same meaning as R "or represents linear alkylene with 3 to 18 carbon atoms; R1A represents lower alkyl; x represents integers from 3 to 5; and represents integers from 1 to 6; R, and Rb, independently of each other, mean H, alkyl with 1 to 8 carbon atoms, cycloalkyl with 3 to 8 carbon atoms, benzyl or phenyl; with the conditions that n in the groups - (??) n "R? be °» when R2 means H, that maximum two Yx of the groups - (Y p- mean 0 as well as n in the other groups - ( Y?) N- are 0, and that n in the group - (Y2) "- is 0, when R3 means a direct link, and where, in addition, X means -0- bivalent ,, -NH-, - S-, lower alkylene or Y10 represents -0- (CH2) v- or a direct bond, where y means integers from 1 to 6 and its terminal CH2 groups is linked to the neighboring X in the formula (IIb); R 100 represents H, alkyl having 1 to 12 carbon atoms, alkoxy with 1 to 12 carbon atoms, alkyl having 1 to 12 carbon atoms-NH- or -NR1AR1B, wherein R1A represents lower alkyl and R1B represents H or lower alkyl; R101 means linear or branched lower alkyl, lower alkylene or aryl-lower alkyl; R102, independently of R101, has the same meaning as this or represents aryl, or R? Oi and Ri02 mean together - (CH2) m-, where m means integers from 2 to 6; R Q3 and Ri04 »independently from each other, mean linear or branched lower alkyl, which may be substituted by alkoxy with 1 to 4 carbon atoms, aryl-lower alkyl or lower alkenyl; or R? 0 and Ri? 4 mean together - (CH2) 2-Yn- (CH2) 2, wherein Yn is a direct bond, -O-, -S- or -NRB and RB is H or lower alkyl and z means an integer from 2 to 4. In a preferred embodiment, Y means O. R? A as alkyl, it may represent, for example, methyl, ethyl, n- or i-propyl, n-, i- or t-butyl, pentyl or hexyl. Preferably, RIA means methyl. The group R contains, as alkyl, alkoxy or alkylNH-, preferably 1 to 6 and particularly preferably 1 to 4 carbon atoms. Some examples are methyl, ethyl, n-or i-propyl, n-, i- or t-butyl, pentyl, hexyl, octyl, decyl, dodecyl, methoxy, ethoxy, propoxy, butoxy and methylNH-. Particularly preferably, R means H. R 1, as alkyl, is preferably linear and preferably contains 1 to 4 carbon atoms. Some examples are methyl, ethyl, n- or i-propyl, n-, i- or t-butyl, pentyl, hexyl, heptyl and octyl. Particularly preferred Ri is methyl or ethyl. R1 t as aryl, can mean, for example, naphthyl and, particularly, phenyl. If both groups R? - (Y?) N ~ mean together - (CH2) X, x is preferably 4 and particularly preferred 5. Rj, as hydroxyalkyl, is preferably linear and preferably contains 1 to 4 carbon atoms. Some examples are hydroxymethyl and 2-hydroxyethyl-1-yl. The same preferences as for R2 are valid for R2. Particularly preferred R2 means H, methyl or ethyl. Ra and preferably represent, independently of one another, H or alkyl with 1 to 4 carbon atoms, for example methyl or ethyl. In a preferred subgroup, Ri means ethyl and, particularly preferred, methyl or the two groups R? - (Y;?) N-together pentamethylene, if n in the group - (Y?) N ~ R2 preferably represents 0, R2 represents preferably methyl, hydroxymethyl or H and R means H. In another preferred embodiment, in the group - (Y?) n ~ R2 Yl represents O, n 1 and R2 H. In particular, in this case n, in the R groups ? - (Y?) N "is °" R3, as alkylene, preferably contains 6 and particularly preferred 1 to 4 carbon atoms and is preferably linear, examples are methylene, ethylene, 1,2- or 1,3-propylene, 1,2-, 1,3- or 1,4-butylene, pentylene, hexylene, heptylene and octylene, methylene, ethylene, 1,3-propylene and 1,4-butylene are preferred. very particularly preferred, R3 represents ethylene, or a direct bond, where n, in the group - (Y2) n, is ° "In the case of R3 as alkylene substituted with hydroxyl, it can be treated, for example, in particular 2-hydroxy-l, 3-propylene or also of 2-hydroxy-l, 3- or 1,4-butylene. Alkylene interrupted with -O- and, optionally, substituted with -OH, is, for example, -CH2CH2-0-CH2CH2, CH2CH2-0-CH2CH2-0-CH2CH2, -CH2CH2-0-CH2CH2-0-CH2CH2- 0-CH2CH2, [-CH (CH3) CH2-0-CH (CH3) CH2-], -CH (CH3) CH2-0-CH2CH2-, -CH (C2H5) CH2-0-CH2CH2-, [-CH ( C2H5) CH2-0-CH (C2H5) CH2-] O -CH2CH2CH2CH2-0-CH2CH2CH2CH2- and -CH2CH (0H) CH2-0-CH2CH2-. Alkylene interrupted with -O-C (O) - or -C (0) -0- is, for example, CH2CH2-C (0) -0-CH2- or -CH2CH2-0-C (0) -CH2-. Alkylene interrupted with -0-C (0) -0- is, for example, -CH2CH2-0-C (0) -CH2CH2- or -CH2CH2-0-C (0) -0-CH2-. In the case of alkyl substituents with 1 to 4 carbon atoms and alkoxy with 1 to 4 carbon atoms, it is preferably methyl, ethyl, methoxy or ethoxy. R contains preferably branched alkylene 3 to 14 and particularly preferred 4 to 10 carbon atoms. Examples for alkylene are 1,2-propylene, 2-methyl- or 2,2-dimethyl-1,3-propylene, 1,2-, 1,3- and 2,3-butylene, 2-methyl- or 2-methyl. , 3-dimethyl-l, 4-butylene, 1,2-, 1,3- or 1,4-pentylene, 2-methyl- or 3-methyl- or 4-methyl- or 2,3-dimethyl-2 , 4-dimethyl or 3,4-dimethyl- or 2, 3, 4-trimethyl or 2,2,3-trimethyl- or 2, 2, 4-trimethyl- or 2, 2, 3, 3-tetramethyl- or 2 , 2,3,4-tetramethyl-1,5-pentylene, 1,2-, 1,3-, 1,4- or 1,5-hexylene, 2-methyl- or 3-methyl or 4-methyl- or 2,2-dimethyl- or 3,3-dimethyl- or 2,3-dimethyl- or 2,4-dimethyl- or 3,4-dimethyl- or 2, 2, 3-trimethyl- 0 2, 2, 4- trimethyl- or 2, 2, 5-trimethyl- or 2, 3, 4-trimethyl- or 2, 2,4,5-tetramethyl-1,6-hexylene. Other examples are disclosed in EP-A-632329. Some preferred branched alkylene radicals are 2,2-dimethyl-1,4-butylene, 2,2-dimethyl-1,5-pentylene, 2. 2.3- or 2, 2,4-trimethyl-l, 5-pentylene, 2, 2, dimethyl-l, 6-hexylene, 2,2,3- or 2,2,4- or 2, 2, 5-trimethyl -l, 6-hexylene, 2,2-dimethyl-l, 7-heptylene, 2,2,3- or 2,2,4- or 2,2,5- or 2,2,6-trimethyl-1, 7-heptylene, 2,2-dimethyl-l, 8-octylene, 2,2,3- or 2. 2.4- or 2,2,5- or 2,2,6- or 2,2,7-trimethyl-l, 8-octylene. When R 4 is arylene, it is preferably naphthylene and particularly preferred phenylene. When the arylene is substituted, a substituent is preferably in the ortho position with respect to an isocyanate group. Examples of substituted arylene are 1-methyl-2,4-phenylene, 1,5-dimethyl-2,4-phenylene, l-methoxy-2,4-phenylene and l-methyl-2,7-naphthylene. R 4 as aralkylene is preferably naphthylalkylene and, particularly preferred, phenylalkylene. The alkylene group in the aralkylene contains preferably 1 to 12, particularly preferred 1 to 6 and especially preferred 1 to 4 carbon atoms. Very particularly preferred, the alkylene group in the aralkylene represents methylene or ethylene. Some examples are 1,3- or 1,4-benzylene, naphth-2-yl-7-methylene, 6-methyl-l, 3- or 1,4-benzylene, 6-methoxy-l, 3- or l, 4-benzylene. When R 4 is cycloalkylene, it is preferably cycloalkylene having 5 or 6 carbon atoms, which is unsubstituted or substituted with methyl. Some examples are 1,3-cyclobutylene, 1,3-cyclopentylene, 1,3- or 1,4-cyclohexylene, 1,3- or 1,4-cycloheptylene, 1,3,3 or 1,4- or 1,5-cycloheptylene. cyclooctylene, 4-methyl-l, 3-cyclopentylene, 4-methyl-l, 3-cyclohexylene, 4,4-dimethyl-1,3-cyclohexylene, 3-methyl- or 3,3-dimethyl-1,4-cyclohexylene , 3, 5-dirrethyl-l, 3-cyclohexylene, 2,4-dimethyl-1,4-cyclohexylene. When R4 is cycloalkylene-CyHjy, it is preferably cyclopentylene-CyH ^ - and particularly cyclohexylene-CyH2y, which is unsubstituted or substituted with 1 to 3 C1-C4 alkyls, particularly preferably methyl. In the group -CyH2y-, and preferably represents integers from 1 to 4. More preferably, the group -CyH2y- represents ethylene and, particularly preferred, methylene. Some examples are cyclopent-l-yl-3-methylene, 3-methyl-cyclopent-l-yl-3-methylene, 3,4-dimethyl-cyclopent-l-yl-3-methylene, 3,4,4-trimethyl -cyclopent, -l-yl, 3-methylene, cyclohex-l-yl-3- or -4-methylene, 3- or 4- or 5-methyl-cyclohex-l-yl-3- or -4-methylene, , 4- or 3, 5-dimethyl, cyclohex-l-yl-3- or -4-methylene, 3,4,5- or 3,4,4- or 3, 5, 5-trimethyl-cyclohex-l- il-3-or -4-methylene. When R4 is -CyH2y-cycloalkylene-CyH2y-, it is preferably -CyHjy-cyclopentylene-CyHjy- and particularly -CyHjy-cyclohexylene-CyHjy-, which is unsubstituted or substituted with 1 to 3 alkyls with 1 to 4 carbon atoms, particularly preferred methyl. In the group -CyH2y-, and preferably represents integers from 1 to 4. More preferably, the group -CyH-jy- represents ethylene and, particularly preferred, methylene. Some examples are cyclopentan-1,3-dimethylene, 3-methyl-cyclopentan-1, 3-dimethylene, 3,4-dimethyl-cyclopentane-1,3-dimethyl, 3,4,4-trimethyl-cyclopentan-1, 3 -dimethylene, cyclohexane-1,3- or -1,4-dimethylene, 3- or 4- or 5-methyl-cyclohexane-1,3- or -1,4-dimethylene, 3,4- or 3,5 -dimethyl-cyclohexane-1,3- or -1,4-dimethylene, 3,4,5- or 3,4,4- or 3,5,5-trimethyl-cyclohexan-1, 3- or -1, 4 -dimethylene. When R5 has the same meaning as R4, the preferences indicated above are also valid. R5 contains as linear alkylene preferably 3 to 12 and particularly preferably 3 to 8 carbon atoms. Some examples for linear alkylene are 1,3-propylene, 1,4-butylene, 1,5-pentylene, 1,6-hexylene, 1,7-heptylene, 1,8-octylene, 1,9-nonylene, 1, 10-decylene, 1,11-undecylene, 1,12-dodecylene, 1,4-tetradecylene and 1,18-octadecylene. In a preferred meaning, X is -O-, -NH-, -S- or lower alkylene. More X is preferred as -0- or -S- and, particularly, as -0-. In a preferred meaning of Yio, the index y represents 1 to 5, more preferably 2 to 4 and extraordinarily preferred 2 to 3, so that YIQ, for example, means ethyleneoxy or propyleneoxy. In another preferred meaning, YIQ means a direct link, wherein X preferably represents or contains at least one hetero atom. The Rioo group contains as alkyl, alkoxy, alkylNH- or -NR? AR? B preferably 1 to 6 and particularly preferably 1 to 4 carbon atoms. Some examples are methyl, ethyl, n- or i-propyl, n-, i- or t-butyl, pentyl, hexyl, octyl, decyl, dodecyl, methoxy, ethoxy, propoxy, butoxy, N, N-dimethylamino and N- methylamino. Particularly preferred, R means H. A preferred meaning of -NRAR? B is N, N-dimethylamino, N-methylamino, N-methyl-N-ethylamino, N-ethylamino, N, N-diethylamino, N-isopropylamino or N, N-diisopropylamino. Rioi preferably means allyl, benzyl, linear alkyl with 1 to 4 carbon atoms, such as methyl or ethyl. Ri02 preferably has the same meaning as Rioi, more preferably is linear lower alkyl with 1 to 4 carbon atoms and, particularly preferably, 1 to 2 carbon atoms. R 2 or 2 # as aryl, can be, for example, naphthyl or particularly phenyl, which is unsubstituted or substituted by lower alkyl or lower alkoxy. When R? O? and Ri02 together represent - (CH2) m-, m is preferably 4 or 5 and particularly preferred 5. Ri03 preferably represents linear lower alkyl with 1 to 4 carbon atoms, benzyl or allyl, and more preferably methyl or ethyl. R104 preferably represents linear lower alkyl with 1 to 4 carbon atoms, and more preferably methyl or ethyl. When R? 03 and R104 mean together - (CH2) Z-Yn- (CH2) Z, Yii is preferably a direct bond, -O- or -N (CH) - and very particularly -0-; z is preferably 2 to 3 and particularly preferred 2. A preferred subgroup of compounds of the formula lia are those wherein, in the groups R? - (Y?) n ~ »n is 0,? 2 2 and i i in the group R- (Y?) N ~ are respectively O, n in the group R2- (Y?) N ~ means 0 or 1, Ri is alkyl with 1 to 4 carbon atoms or phenyl or the groups R? - (Y?) n ~ together represent tetramethylene or pentamethylene, R2 represents alkyl with 1 to 4 carbon atoms or H, R means hydrogen, n in the group - (Y2) -n represents 0 or 1, R3 is linear or branched alkylene, with 2 to 4 carbon atoms or in direct bond, wherein n in the group - (Y2) - n © s 0, R is branched alkylene with 5 to 10 carbon atoms, phenylene or substituted phenylene with 1 to 3 methyl groups, benzylene or benzylene substituted with 1 to 3 methyl groups, cyclohexylene or cyclohexylene substituted with 1 to 3 methyl groups, cyclohexyl-CyH2y- or -CyH2y-cyclohexyl-CyH2y- or cyclohexyl-CyH2y- or -CyHy- cyclohexyl-CyH and- substituted with 1 to 3 methyl groups, R5 has the indicated meanings for R or means linear alkylene with 3 to 10 carbon atoms, and represents 1 or 2. A preferred subgroup of compounds of the f formula are those in which, in the groups R? - (Y?) n ~ y ~ (? 2) ~ n / n is 0, Y, Y2 and i in the group R2- (Y?) n ~ are respectively O , n in the group R2- (Y?) n ~ means 0 or l, R2 is methyl or phenyl or the groups R? _ (Y?) n ~ represent pentamethylene together, R represents methyl or H, R means hydrogen, n in the group - (Y2) -n represents 1 and R3 is ethylene, on in the group - (Y2) -n is 0 and R3 is a direct bond, R4 is branched alkylene with 6 to 10 carbon atoms, phenylene or phenylene substituted with 1 to 3 methyl, benzylene or benzylene groups substituted with 1 to 3 methyl groups, cyclohexylene or cyclohexylene substituted with 1, 3 methyl groups, cyclohexyl-CH2- or cyclohexyl-CH2- substituted with 1 to 3 methyl groups, and R5 has the meanings indicated for R 4 or means linear alkylene with 5 to 10 carbon atoms. A preferred subgroup of compounds of formula IIb are those wherein R101 means linear lower alkyl, lower alkenyl or aryl-lower alkyl; R102, independently of R101, has the same meaning as this or means aryl; R103 and R104, independently of each other, represent straight or branched lower alkyl, which may be substituted by alkoxy with q to 4 carbon atoms, aryl-lower alkyl or lower alkenyl; or R103 and R104 mean together - (CH2), -Y- (CH2) z, wherein Y ^ is a direct bond, -0-, -S- or -NR1B and R1B means H or lower alkyl and z is a whole number from 2 to 4; and R5 means linear or branched alkylene with 3 to 18 carbon atoms, arylene with 6 to 10 carbon atoms, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or alkoxy with 4 carbon atoms, or aralkylene with 7 a 18 carbon atoms, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, arylenenalkarylene with 13 to 24 carbon atoms, unsubstituted or substituted with alkyl having 1 to 4 carbon atoms or C 1 -C 4 alkoxy, C 3 -C 8 cycloalkylene-CyHjy-, unsubstituted or substituted by C 4 -alkyl or C 1 -C 4 -alkoxy or -CyHjy- (cycloalkylene with 3 a 8 carbon atoms) -CyH ^ -, unsubstituted or substituted by alkyl with 1 to 4 carbon atoms or alkoxy with 1 to 4 carbon atoms, where y represents an integer from 1 to 6.

A preferred subgroup of compounds of the formula Ilb are those wherein X means -O- bivalent, -NH, --S- or - (CH2) and ~; Yio represents -0- (CH2) and or a direct bond, where y is an integer from 1 to 6 and whose terminal CH group is linked to the neighboring X in the formula (Ilb); Rioo is H, alkyl with 1 to 12 carbon atoms or alkoxy with 1 to 12 carbon atoms; Rioi represents linear lower alkyl, lower alkynyl or aryl-lower alkyl; R? O2r independently of Roi, has the same meaning as this or means aril, or Rioi and i02 mean together - (CH) m-, where m is an integer from 2 to 6; R3O3 and R4O4 * independently from each other, represent linear or branched lower alkyl, which may be substituted by alkoxy with 1 to 4 carbon atoms, aryl-lower alkyl or lower alkenyl; or R? 03 and R104 mean together - (CH2) Z-Yn ~ (CH2) z, where Yu is a direct bond, -O-, -S- or -NR1B and R1B is H or lower alkyl and z is a number whole from 2 to 4; and R5 represents branched alkylene with 6 to 10 carbon atoms, phenylene or phenylene substituted with 1 to 3 methyl, benzylene or benzylene groups substituted with 1 to 3 methyl groups, cyclohexylene or cyclohexylene substituted with 1 to 3 methyl groups, cyclohexyl-CH2- or cyclohexyl-CH2- substituted with 1 to 3 methyl groups. A particularly preferred subgroup of compounds of formula Ilb are those in which Rioi means methyl, allyl, toluylmethyl or benzyl, Ri02 means methyl, ethyl, benzyl or phenyl or RIQI and R102 together represent pentamethylene, 103 and Ri04c independently of each other, represent alkyl lower with up to 4 carbon atoms or R103 and Ri04 together signify -CH2CH2OCH2CH-, and R5 represents branched alkylene with 6 to 10 carbon atoms, phenylene or phenylene substituted with 1 to 3 methyl, benzylene or benzylene groups substituted with 1 to 3 groups methyl, cyclohexylene or cyclohexylene substituted with the 3 methyl groups, cyclohexyl-CH2- or cyclohexyl-CH2- substituted with 1 to 3 methyl groups. In the case of groups R4 and R5, they are particularly those which reduce the reactivity of the OCN group, which is basically achieved by steric hindrance or by electronic influences on at least one neighboring carbon atom. Therefore, R 4 and R 5 are preferably, among other things, non-symmetrical radicals, for example branched alkylene, in the - or in particular β position with respect to the OCN group, or hydrocarbon radicals, substituted as defined, in at least one position to. In the context of the present invention, a copolymerizable vinyl monomer is understood in particular as a monomer containing a vinyl group and which has already been mentioned in connection with copolymers which found application in contact lenses. By a vinyl group it is understood in this context not exclusively the vinyl group "-CH = CH2", but in general any grouping that has a carbon-carbon double bond. The especially preferred meanings of the textual component "vinyl" in vinyl monomers are obtained in the following explanations in relation to compounds of the formula III. In the sense of this invention, the copolymerizable vinyl monomers were already disclosed in EP-A-374, 752, EP-A-417, 235 and EP-A-455,587. In particular, the monomers from which the component A of the formula I is split for the vinyl telomers according to the invention, the block copolymers, the polymerizable compounds, the polymers or the contact lenses, are compounds of the Formula III, which, symbolized by the letter A, are incorporated into the vinyl telomer of formula I, in the form of a partial formula IV, wherein the substituents, X0, Y0 and z have the following meanings: three of these substituents mean hydrogen and the fourth substituent is selected from acyl, halogen, a heterocyclic or aryl radical, or two of these substituents are hydrogen, the third is lower alkyl and the fourth is chosen from acyl, halogen, a heterocyclic radical or aryl, or two of these substituents mean hydrogen and the other two together form a hydrocarbon bridge, which is uninterrupted or interrupted by one or two heteroatoms, the other two substituents mean, independently of each other, acyl. The monomers of formula III are either hydrophilic vinyl monomers or hydrophobic vinyl monomers. Preferably, those copolymerizable vinyl monomers used to obtain the vinyl telomers of the formula I do not have any H-active group, at least no deprotected H-active group. These are referred to below as vinyl monomers of group I. With respect to these, those vinyl monomers which are used for the preparation of polymerizable compounds of formula C, expressly have at least one H-active group. These are then referred to as vinyl monomers of group C. Aryl is particularly an aromatic hydrocarbon radical with 6 to 15 carbon atoms, such as phenyl or phenyl substituted by one or more, in particular up to three, radicals of the lower alkyl type , lower alkoxy, halogen, amino or hydroxyl. Examples are phenyl or tolyl. Halogen means particularly chlorine, bromine or fluorine, but can also represent iodine. A heterocyclic radical is in particular a 5- or 6-membered ring, aromatic or saturated, with one or two heteroatoms, such as oxygen or nitrogen atoms, in particular with one or two nitrogen atoms. In the above, lactams are also included. A hydrocarbon bridge, uninterrupted or interrupted by one or two heteroatoms, means in particular lower alkylene or lower alkylene interrupted by oxygen or nitrogen. The lower alkylene interrupted by nitrogen may also be substituted, for example, by lower alkyl. Examples are 1,3-propylene, 2-aza-l, 3-propylene or N-methyl-2-aza-l, 3-propylene. Acyl represents carboxyl, aroyl, cycloalkanoyl or alkanoyl and, particularly, carboxyl, unsubstituted or substituted aryloxycarbonyl, unsubstituted or substituted cycloalkyloxycarbonyl or unsubstituted or substituted alkoxycarbonyl. Aroyl means, for example, benzoyl or benzoyl substituted by one or more, particularly one to three, radicals of the lower alkyl, lower alkoxy, halogen or hydroxyl type, but can also mean phenylsulfonyl or phenyloxysulfonyl, as well as phenylsulfonyl or phenyloxysulfonyl substituted by lower alkyl , lower alkoxy halogen or hydroxyl. Alkanoyl preferably means lower alkanoyl and is, for example, acetyl, propanoyl or butanoyl. Cycloalkanoyl means preferably cycloalkyloxycarbonyl with up to 8 carbon atoms and means, for example, cyclohexyloxycarbonyl. Unsubstituted alkoxycarbonyl is preferably lower alkoxycarbonyl and means, for example, methoxycarbonyl, ethoxycarbonyl, propyloxycarbonyl, butoxycarbonyl, tertiary butoxycarbonyl, tertiary butylmethyloxycarbonyl or 2-ethylhexyloxycarbonyl. Unsubstituted aryloxycarbonyl is preferably phenyloxycarbonyl. Substituted alkoxycarbonyl is preferably phenyloxycarbonyl preferably substituted by one or more, in particular up to three, radicals of the lower alkyl, lower alkoxy, halogen or hydroxyl type. Substituted alkoxycarbonyl is preferably substituted by hydrophobic groups, such as halogen, for example, fluorine, siloxane groups or hydrophilic groups, such as hydroxyl, amino mono- or di-lower alkyl-amino, isocyanate or by a lower alkylene glycol. Other meanings of substituted alkoxycarbonyl, as well as substituted aryloxycarbonyl and substituted cycloalkyloxycarbonyl, are implicitly given by the following description of especially suitable vinyl monomers of formula III. The hydrophilic vinyl monomers to be used according to the invention, preferably acrylates and methacrylates of the formula III, wherein W and Y0 represent hydrogen, X0 represents hydrogen or methyl and Z means a group -Z1-Z2, wherein Z1 represents -C00-, which is bonded to Z2. through oxygen, and Z means a hydrocarbon radical with 1 to 10 carbon atoms, substituted once or several times by a group which achieves solubility in water, such as carboxyl, hydroxyl or non-tertiary, for example, lower alkylamino with 1 to 7 carbon atoms per lower alkyl group, a polyethylene oxide group with 2 to 100 repeating units, preferably with 2 to 40 repeating units, or a sulfate, phosphate, sulfonate or phosphonate group; such as, for example, a correspondingly substituted alkyl, cycloalkyl or phenyl radical or a combination of said radicals, such as phenylalkyl or alkylcycloalkyl; further acrylamides and methacrylamides of the formula III, wherein Y0 is hydrogen, X0 is hydrogen or methyl, and Z represents aminocarbonyl or di-lower alkyl-aminocarbonyl; the acrylamides and methacrylamides of the formula III, wherein W and Y0 signify hydrogen, X 0 signifies hydrogen or methyl and Z represents monosubstituted aminocarbonyl, which is substituted by a group Z 2 defined as indicated above or by lower alkyl; aleinates and fumarates of the formula III, wherein W and X0 (or W and Z) represent hydrogen, and Y0 and Z (or X0 and Y0), independently of each other, mean a group -Z -Z2, wherein Z1 and Z2 are defined as indicated above; crotonates of the formula III, wherein and X0 signify hydrogen, YQ signifies methyl and Z represents a group -Z1-Z 2, wherein Z1 and Z2 are defined as indicated above; vinyl ether of the formula III, wherein X0 and Y0 represent hydrogen and Z means a group -Z 1 -Z2, wherein Z 1 is oxygen and Z 2 is defined as indicated above; five or six membered heterocycles, vinylsubstituted, with one or two nitrogen atoms, as well as N-vinyllactams, such as N-vinyl-2-pyrrolidone, of the formula III, wherein W, X0 and Y0 mean hydrogen and Z represents a five or six membered heterocyclic radical, with one or two nitrogen atoms, as well as the radical of a lactam linked through nitrogen, for example that of 2-pyrrolidone; and vinyl unsaturated carboxylic acids of the formula III, with in total 3 to 10 carbon atoms, such as methacrylic acid, crotonic acid, fumaric acid or cinnamic acid. Preferred are, for example, alkyl (meth) acrylates with 2 to 4 carbon atoms, substituted by hydroxyl or amino, N-vinyllactams of five to seven members, N, N-di-alkyl (meth) acrylamides with 1 to 4. carbon atoms and vinyl unsaturated carboxylic acids with in total 3 to 5 carbon atoms. Among them, N-vinyl lactams of five to seven members and N, N-di-alkyl (meth) acrylamides with 1 to 4 carbon atoms are vinyl monomers of group I, while alkyl (meth) acrylates with 2 to 4 carbon atoms, substituted by hydroxyl or amino and the vinyl unsaturated carboxylic acids having in total 3 to 5 carbon atoms are vinyl monomers of group C. The difference of the vinyl monomers mentioned above and then in representatives of the type group I and of the type group C is not carried out here for all the representatives, since the differentiation can be easily found based on the criterion of whether there is an H-active group or not. Both groups of vinyl monomers are considered to be independently developed from each other based on this differentiation criterion. A water-soluble monomers which can be used belong: 2 - hydroxyethyl-, 2- and 3-hydroxypropyl, 2,3- dihydroxypropyl, and polyethoxypropylacrylates polietoxietil- and methacrylates, and the corresponding acrylamides and methacrylamides, acrylamide and methacrylamide, acrylamide and methacrylamide N-, bisaceton-acrylamide, 2- hydroxyethyl acrylamide, dimethylacrylamide and methacrylamide, methylolacrylamide and methacrylamide and N, N-dimethyl- and N, N-diethylaminoethyl acrylate and methacrylate, and the corresponding acrylamide and methacrylamide, N-tert-butylamino-ethyl methacrylate and methacrylamide-, 2- and 4-vinylpyridine, 4- and 2-methyl-5-vinylpyridine, N-methyl-4-vinylpiperidine, 1-vinyl- and 2 methyl-l-vinylimidazole, allylamine and dimethyl-methyldiallylamine and para-, meta- and ortho-aminostyrene, dimethyl aminoetilviniléter, N-vinylpyrrolidone and 2-pirrolidinoetilmetacrilato, acrylic and methacrylic acid, itaconic acid, cinnamic acid, crotonic acid, fumaric acid, acid maleic and its hydroxy-lower alkyl-mono- and -di-esters, such as 2-hydroxyethyl- and di- (2-hydroxy) -ethyl-fumarate, -maleinate and -itaconate, as well as 3-hydroxypropyl-butyl fumarate and di-poly -alcoxialquil-fumarates, maleates and itaconates, anhydrous maleic acid imide, N-methyl-maleic acid, sodium acrylate and methacrylate, 2-methacryloyloxyethylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-fosfatoetilmetacrilato, vinylsulfonic acid, phenylvinylsulfonate, sodium vinylsulfonate, p-styrenesulfonic acid, sodium-p-styrenesulfonate and allylsulfonic acid, N-vinylpyrrolidone, N-vinylpyridone, N-vinylcaprolactam, plus the quaternized derivatives of cationic monomers, which are obtained by quaternization with selected alkylating agents, for example, halogenated hydrocarbons such as methyl iodide, benzyl chloride or hexadecyl chloride, epoxies such as glycidol, epichloridrine or ethylene oxide, acrylic acid, dimethyl sulfate, methyl sulfate and propansulfone. A complete list in relation to the water soluble monomers, employable with this invention, is found in: R.H. Yocum and E.B. Nyquist, Functional Monomers (Functional Monomers), volume 1, pp. 424-440 (M. Dekker, N.Y. 1973). Preferred hydrophilic vinyl monomers are 2-hydroxyethylmethacrylate, 3-hydroxypropylmethacrylate, N-vinyl-2-pyrrolidone, polyethylene glycol methacrylate, particularly with a portion of ethylene glycol having a molecular weight of about 400, N, N-dimethylacrylamide, N, N-diethylamide Inethyl (meth) acrylate, as well as acrylic and methacrylic acid. Examples of hydrophobic vinyl monomers which can be used according to the invention are, for example, acrylates and methacrylates of the formula III, in which W and Y0 represent hydrogen, X0 represents hydrogen or methyl and Z represents a group -Z 1 -Z 3, wherein Z 1 represents -COO-, which is linked to Z through oxygen, and Z means an aliphatic, cycloaliphatic or aromatic, linear or branched group, with 1 to 21 carbon atoms, as for example a correspondingly substituted alkyl, cycloalkyl or phenyl radical, or a combination of said radicals, such as phenylalkyl or alkylcycloalkyl, which may contain the ether or thioether linkages, sulfoxide or sulfone groups or a carbonyl group; or Z is a heterocyclic group, which contains atoms of oxygen, sulfur or nitrogen and 5 or 6, or if it is bicyclic, up to 10 ring atoms, or a polypropylene oxide group or poly-n-butylene oxide with 2 to 50 recurring alkoxy units, or Z is an alkyl group with 1 to 12 carbon atoms, which contains halogen atoms, particularly fluorine atoms, or Z is a siloxane group with 1 to 6 Si atoms; acrylamides and methacrylamides of the formula III, wherein W and Y0 mean hydrogen, XQ means hydrogen or methyl and Z represents monosubstituted aminocarbonyl, which e > . is replaced by a group Z defined as indicated above; maleinates and fumarates of the formula III, where y X0 (or W and Z) represent hydrogen, and Y0 and Z (or X0 and Y0), independently of each other, mean a group -Z -Z3, where Z and Z are defined as indicated above; Itaconates of the formula III, wherein W and Y0 mean hydrogen, XQ means a group -Z1-Z3, wherein Z1 and Z3 they are defined as above and Z is a group -CH2-Z1-Z3, wherein Z1 and Z3 are defi ned as above; crotonates of the formula III, wherein W and X0 mean hydrogen, Me means methyl and Z represents a group -Z-Z 3, wherein Z1 and Z3 are defined as above; vinyl ester of the formula III, wherein, Y0 and Xo represent hydrogen and Z means a group -Z -Z, where Z is -C00-, which is bonded to Z through carbon, and Z is defined as indicated above; vinyl ether of the formula III, wherein, X0 and Y0 represent hydrogen and Z means a group -Z -Z, wherein 1 Z is oxygen and Z is defined as above. Particularly preferred are alkyl ester having 1 to 4 carbon atoms or cycloalkyl ester having 5 to 7 carbon atoms of vinyl unsaturated carboxylic acids with 3 to 5 carbon atoms. Examples of suitable hydrophobic monomers are: methyl-, ethyl-, propyl-, isopropyl-, butyl-, isobutyl-, tert.-butyl-, ethoxyethyl-, methoxyethyl-, benzyl-, phenyl-, cyclohexyl-, trimethylcyclohexyl-, isobornyl-, dicylopentadienyl-, norbornylmethyl-, cyclododecyl-, 1,1,3,3-tetramethylbutyl-, n-butyl, n-octyl, 2-ethylhexyl-, decyl-, dodecyl-, tridecyl-, octadecyl-, glycidyl- , ethylthioethyl-, furfuryl-, tri-, tetra- and pentasiloxanepropyl acrylates and -methacrylates, as well as the corresponding amides; N- (1, 1-dimethyl-3-oxobutyl) -acrylamide; mono- and dimethyl-f-arate, -maleate and -itaconate; diethyl fumarate; isopropyl- and diisopropyl fumarate and itaconate; mono- and diphenyl- and methylphenyl fumarate and itaconate; methyl- and ethylcrotonate; methyl vinyl ether and methoxyethyl vinyl ether; vinyl acetate, vinyl propionate, vinyl benzoate, acrylonitrile, vinylidene chloride, styrene, α-methylstyrene and tert-butylstyrene. Preferred hydrophobic vinyl monomers are methyl methacrylate, n-byl methyl methacrylate, isopropyl methacrylate, isobutyl methacrylate, cyclohexyl methacrylate or a mixture thereof. Among the aforementioned vinyl monomers, two special types of hydrophobic vinyl monomers, namely siloxanomonovinyl components and fluorine-containing vinyl compounds, should be mentioned particularly in the context according to the invention. Particularly preferred siloxanomonovinyl components are the compounds of formula III, wherein W and I mean hydrogen, X 0 signifies hydrogen or methyl and Z represents a group -Z 1 -Z 4, where Z 1 means -C00-, which is bonded to Z through oxygen, and wherein Z is a silyl-lower alkyl substituted one or several times, for example, three to nine times by tri-lower alkyl-silyloxy. By silyl-lower alkyl is meant in this context a lower alkyl radical substituted by one or more silicon atoms, whose free valences are saturated in the silicon atoms, in particular by tri-lower alkyl-silyloxy. The individual compounds to be especially emphasized are, for example, tris (tri-methylsiloxy) silylpropyl ethacrylate and tris (tris (trimethylsiloxy) siloxy) silylpropyl methacrylate. Particularly preferred fluorine-containing vinyl compounds are the compounds of formula III, wherein E means hydrogen, XQ means hydrogen or methyl, and Z is a group Z -Z, where Z means -COO-, which is bonded to Z through oxygen, and wherein Z means alkyl substituted by fluorine, particularly lower alkyl. The special axes of the foregoing are 2, 2, 2-trifluoroethylmethacrylate, 2,2,3,3-tetrafluoropropylmethacrylate, 2,2,3,3,4,4,5,5-octafluorpentyl methacrylate and hexafluorisopropylmethacrylate. As already mentioned, the polymers according to the invention are preferably obtained starting from a compound of the formula C or D, optionally a vinyl monomer, and in the presence of a crosslinker. Suitable vinyl crosslinkers are, in particular, oligoolefin monomers, particularly diolefin monomers, for example, allyl acrylate and methacrylate., ethylene glycol-, diethylene glycol-, triethylene glycol-, tetraethylene glycol- and in general diacrylates and glycol dimethylacrylates of polyethylene oxide, 1,4-butanediol- and glycol diacrylates and dimethylacrylates of poly-n-butylene oxide, thiodiethylene glycol diacrylates and dimethylacrylate, di- (2-hydroxyethyl) -sulfondiacrylate and dimethylacrylate, neopentylglycoldiacrylate and dimethylacrylate, trimethylolpropane-tri- and -tetraacrylate, pentaerythritol-tri- and -tetra-acrylate, divinylbenzene, divinyl ether, divinyl sulphone, disiloxanyl-bis-3-hydroxypropyl-diacrylate or-methacrylate and related compounds. Ethylene glycol dimethacrylate is preferred. Suitable crosslinkers are oligovinyl macromers, for example, divinyl macromers, as described, for example, in US-A-4,136,250. In addition, as crosslinking agents in the context according to the invention, oligovinylsiloxane compounds are also suitable, for example, bis (meth) -acyloxy-lower alkyl siloxanes with up to 10 silicon atoms. Examples thereof are 3,5-bis (3-methoxyloxypropyl) -3,5-bis (trimethylsiloxy) -1,1,7,7,7-hexamethyltetrasyl-oxane and 1,3-dimethacryloxypropyl-tetramethyldisiloxane. The starting materials which are used in the preparation of the vinyl telomers according to the invention, the segmented copolymers, the polymerizable compounds and the polymers, for example those of the formulas A, B, III and the crosslinking agents, are in themselves known and / or described in this document. The compounds of formula II can be obtained in a manner known per se by the conversion of diisocyanates with the corresponding H-acid photoinitiators. The compounds are obtained in high yields and purities, even when in the photoinitiator there are at the same time two different H-acid reactive groups, for example two OH groups. It is particularly advantageous to use diisocyanates with isocyanate groups of various reactivity, since the formation of isomers and diaducts can be greatly inhibited. The various reactivity can be achieved, for example, as described above, by a steric hindrance. The diverse reactivity can also be achieved by a decay of an isocyanate group in the diisocyanate, for example, with carboxylic acids or hydroxyamine. The compounds of the formula Ilia are known from EP-A-632329. The compounds of the formula (Ilb) can be obtained by reacting, preferably in an inert organic solvent, a compound of the formula wherein X, Y, R, Rlf R, R and R 4 have the meanings indicated above, with a diisocyanate of the formula lid or with a diisocyanate of this type, optionally mono-inked, OCN-R5-NCO Old), where R5 has the meaning indicated above. Decaying agents are known from urethane chemistry. It can be, for example, phenols (cresol, xyleneol), lactams (e-caprolactam), oximes (acetoxime, benzophenone oxime), methylene compounds H-active (diethylmalonate, ethylacetoacetate), pyrazoles or benztriazoles. The decapting agents are described, for example, by Z. icks, Jr. in Progress in Organic Coatings, 9 (1981), pp. 3-28. The educts of the type of the formula lie are known and are described in EP-A-284,561, EP-A-117,233 or EP-A-088,050. Suitable inert solvents are aprotic, apolar or polar solvents, such as hydrocarbons (petroleum ether, methylcyclohexane, benzene, toluene, xylene), halogenated hydrocarbons (chloroform, methylene chloride, trichlorethane, tetrachloroethane, chlorbenzene), ether (diethyl ether, dibutyl ether, ethylene glycol ethyl ether, diethylene glycol dimethyl ether, tetrahydrofuran (THF), dioxane), ketones (acetone, dibutyl ketone, methyl isobutyl ketone), carboxylic acid ester and lactones (acetic acid ethyl ester, butyrolactone, valerolactone), alkylated acid amides carboxylic (N, N-dimethylacetamide (DMA) or N, N-dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP)), nitriles (acetonitrile), sulfones and sulfoxides (dimethylsulfoxide (DMSO), tetramethylsulfone). Preferably, polar solvents are used. The reactants are advantageously used in equimolar amounts. The reaction temperature can be from 0 to 200SC. In case of using catalysts, the temperatures can conveniently be in the range of -200 to 602C and preferably in the range of -10a to 502C. Suitable catalysts are, for example, metal salts such as alkali metal salts of carboxylic acids, tertiary amines, for example (alkyl having 1 to 6 carbon atoms) 3N (triethylamine, tri-n-butylamine), N-methylpyrrolidine, N-Rethylmorpholine, N, N-dimethylpiperidine, pyridine and 1,4-diaza, bicyclooctane. Particularly effective are the tin compounds, particularly the alkyl-tin salts of carboxylic acids, such as, for example, dibutyltin dilaurate, or, for example, tin dioctoate. If in the compounds of the formula there are free NH groups, during the reaction with a diisocyanate, these can be protected first with suitable protecting groups and then, by dissociation of the protecting groups, they can be re-released. Suitable protecting groups are known to the person skilled in the art. Representative examples can be seen, for example, in T. Greene, "Protective Groups in Organic Synthesis", Wiley Interscience, 1981. The isolation and cleaning of the obtained compounds is carried out according to known procedures, such as for example extraction, crystallization, recrystallization or chromatographic cleaning methods. The compounds are obtained in high yields and purities. The returns in the case of a non-optimized procedure can be more than 85% of the theory. The transformation of a copolymerizable vinyl monomer, which is incorporated in the vinyl telomer as component "A", with a photoinitiator of the formula B, can be carried out in a manner known per se. Thus, a vinyl monomer, incorporated in the vinyl telomer as component "A", can be polymerized at room temperature or at a temperature up to the boiling point of the solvent optionally used, in the absence or presence of a suitable solvent. A suitable solvent is characterized in this context because it does not contain any H-active hydrogen atom that can react with the isocyanate group, and because it does not absorb UV light. Examples of them are, for example, a hydrocarbon, particularly cycloaliphatic, such as hexane, methylcyclohexane, benzene or toluene, a ketone, such as acetone, methylisopropyl ketone or cyclohexanone, an ester such as ethyl acetate, a fluorinated solvent such as hexafluoroacetone, an ether of cyclic preference, such as diethyl ether, dimethoxyethane, dioxane or tetrahydrofuran, or an amide, such as N-methylpyrrolidone or DMA, or dimethyl sulfoxide or acetonitrile, or a mixture of several of these solvents. The cleaning is carried out in a manner known per se. For the crosslinking reaction to obtain the polymers according to the invention, basically the same conditions can be used. It is advantageous to control the transformation in such a way that the vinyl telomeres that form are precipitated and can be continuously removed from the reaction mixture by continuous filtration. It is also advantageous when using solvents that exert a sensitizing or accelerating effect on the photopolymerization. An advantageous control of the reaction can be that it is converted only to a consumption of approximately 40% of vinyl monomer, to avoid by-products. This is particularly true when all the components are found from the start in the reaction mixture, because then, relatively quickly, a photoinitiator increase may occur, which favors the possibility of formation of non-NCO- homopolymers. terminal. Alternatively to the above, it may be advantageous to simultaneously dose a monomer solution as well as a solution of the photoinitiator during UV irradiation. The transformation of a vinyl telomer of the formula I with a vinyl monomer to obtain a compound of the formula C can be carried out in a simple manner and is known in the urethane chemistry. The above is also valid for the transformation of a vinyl telomer of the formula I with a macromer of the formula A. The preparation of the polymers according to the invention can be carried out in a manner known per se, for example, under the conditions indicated previously, it is not necessary at this stage of the process that the solvents are free of H-active groups. Suitable olefins of the graft polymerization are, for example, acrylamide, N, N-dimethylacrylamide, methacrylamide, hydroxyethyl methacrylate, glyceryl methacrylate, oligoethylene oxide mono and bisacrylate, ethylene glycol dimethyl acrylate, methylene bisacrylamide, vinyl caprolactam, acrylic acid, methacrylic acid, monovinyl ester of fumaric acid, vinyl trifluoroacetate and vinyl carbonate, it being possible, if appropriate, to subsequently hydrolyze the reactive esters. An acceleration of the photopolymerization can be achieved by adding photosensitizers, which either displace or extend the spectral sensitivity. These are in particular aromatic carbonyl compounds, such as, for example, thioxanthon-, anthraquinone and 3-acylcumarin derivatives, as well as 3- (aroylmethyl) thiozolines. The effectiveness of the photoinitiators can be raised by the addition of titanocene derivatives with fluororganic radicals, as described in EP-A-122,223 and EP-A-186,626, for example, in an amount of 1 to 20% . Examples of said titanocenes are bis (ethylcyclopentadienyl) -bis (2,3,6-trifluorophenyl) -titanium, bis (cyclopentadienyl) -bis- (4-dibutylamino-2, 3,5,6-tetrafluorophenyl) -titanium, bis (methylcyclopentadienyl) -2- (trifluoromethyl) phenyl-titanium-isocyanate, bis (cyclopentadienyl) -2- (trifluoromethyl) phenyl-titanium-trifluoroacetate or bis (methylcyclopentadienyl) -bis- (4-decyloxy-2, 3, 5, 6 -tetrafluor-phenyl) -titanium. Especially suitable for these samples are liquid a-amino ketones. In particular, molded bodies, in particular contact lenses, can be manufactured from the polymers according to the invention in a manner known per se. For this, for example, the polymers according to the invention are polymerized in a cylindrical mold, and the arras obtainable after molding, are divided into discs or buttons, which can be further processed mechanically, in particular by the rotation procedure. Furthermore, the shaped bodies according to the invention or the contact lenses can also be manufactured according to other methods known per se, such as casting in static molds, spin casting, pressing, deep drawing, hot forming, twisted or processed with laser. These steps of the process are known per se and therefore, for the person skilled in the art, do not require a detailed explanation. The production is preferably carried out under an inert atmosphere, if carried out in open molds. As is known, oxygen inhibits polymerization and leads to prolonged polymerization times. If closed molds are used for the polymerization formation, the molds are advantageously made of inert materials with low oxygen permeability and with anti-adhesion characteristics. Examples for suitable materials for molds are polytetrafluoroethylene, such as Teflon *, silicone rubber, polyethylene, polypropylene and polyester such as Mylar *. If a suitable molding agent is used, glass and metal molds can also be used.

Casting in static molds, for example if molds with internal and external curves are used, can lead directly to contact lenses. Thus, contact lenses can be manufactured directly by polymerization in suitable molds (full mold process) or with only one finished surface ("semi mold" process). Spin casting can also be applied according to the invention, by arranging a solution of the starting materials according to the invention in a mold for spin casting, and then the mold is rotated. In this way the solvent evaporates. The finished contact lens, whose dimensions can be controlled by the dimensions of the mold, the rotational speed and the viscosity of the introduced solution, remains in the mold. According to the invention, the pressing takes place, for example, by the compression molding of a sheet of the polymer according to the invention. A film of the polymer can be obtained in a manner known per se, for example by casting a solution. From a manufactured sheet, for example, as mentioned above, a contact lens can also be manufactured in a known manner by deep drawing or hot forming. Turning is offered as the last stage of the process for manufacturing contact lenses according to the invention. This is always valid when a raw part obtainable, for example, according to one of the aforementioned processes, requires further processing. By "turning" is meant the process of treatment with chip removal, as is known, of contact lens blanks. . The corresponding blanks, for example, by extruding round bars and their partitioning or casting, can be manufactured from a solution. Under the term blank piece contact lenses come in this context buttons (buttons) or semi-mold products, such as raw parts of internal curves. Typical blanks have thicknesses of 4 or 6 mm and a diameter of 10 to 17, for example 12 or 14 mm. For soft materials it may be necessary to freeze them before a corresponding processing, in particular below the softening point, and , if necessary, keep the temperatures required for processing during processing. The laser processing can also be applied according to the invention, starting from blanks or contact lenses manufactured according to one of the other methods, if they still require a fine processing of their surfaces. The coating of a surface with a vinyl telomer of the formula I is carried out in a manner known per se, the isocyanate group of the vinyl telomer reacting with H-active groups on the surface. The surface already contains corresponding H-active groups or these are first produced on the surface in a manner known per se, for example by plasma treatment (reference is made, for example, to WO 94/06485). The coating process according to the invention can be characterized by the following steps: a) the surface to be coated, if it does not already contain H-active groups, by means of a chemical or physical treatment, for example, a plasma treatment, is provided H-active groups which are coreactive with isocyanate groups, in particular R groups - H, where R, independientemente independently from each other, means -0 -, - NRH- or -S-, where RH represents hydrogen or lower alkyl, b) the surface containing H-active groups, which are coreactive with the isocyanate groups, is contacted with a vinyl telomer of the formula I, as described above, forming the isocyanate groups of the vinyl telomer , covalent bonds with the H-active groups of the surface. In the case of surfaces, it is preferably contact lens surfaces. The structure of the surface layers obtained corresponds to a so-called brush structure, which is very advantageous.

The following examples illustrate the object of the invention, but without limiting it, for example, to the scope of the examples. The percentages in the quantity indications are percentages by weight if it is not expressly indicated otherwise. In the following examples, the temperatures, if not otherwise indicated, are revealed in degrees centigrade, the molecular weights, as in the rest of this description, are average molecular weights (denomination: "Mw"), if not expressly indicated another thing. In this description of the invention, the vinyl telomers according to the invention are also referred to as phototelóeros.

Examples A: Obtaining OCN-functional photoinitiators Example Al: Obtaining In a 500 ml flask with reflux condenser, thermometer, stirrer and nitrogen inlet tube, under nitrogen, a solution of 11,125 g (0.05 mol) of freshly distilled isophorondiisocyanate (IPDI) in 50 ml of dry methylene chloride is mixed. , with a solution of 11.2 g (0.05 mol) of 4 • - (b-hydroxyethoxy) -2-hydroxyprop-2-yl-phenone (Darocure® 2959) in 300 ml of dry methylene chloride and, after adding 20 mg of dibutyltin dilaurate as catalyst, is stirred 48 hours at room temperature. The course of the reaction is followed by thin layer chromatography on silica gel plates (60 F254, Art. 5719 Merck) (eluent: toluene / acetonitrile 7: 3). The product that is formed, by column chromatography with silica gel 60 (eluant toluene / acetonitrile 7: 3), is released from small amounts of untransformed Darocure® 2959 and IPDI substituted twice. After concentrating the clean fractions on the rotary evaporator, a colorless oil is obtained which crystallizes slowly on cooling to -162C and then recrystallized from diethyl ether. 15.6 g of a white crystalline product are obtained (70% of the theory), which has a melting point of 76SC. The isocyanate content of the product is determined by titration with dibutylamine in toluene; calculated 2,242 mVal / g, found 2.25 mVal / g. The method is described in "Analytical Chemistry of Polyurethanes "(High Polymer Series XVI / Part III, D.S. David + H.B. Staley editors, Interscience Publishers, New York 1969, p.86).

Example A2: Obtaining Analogously to example Al, 10.5 g (0.05 mol) of 1,6-diisocyanato-2,2,4-trimethylhexane (TMDI) are reacted with 11.1 g (0.05 mol) of Darocure * 2959 in 400 ml of dry methylene chloride, at room temperature, under nitrogen, for 40 hours. 14.5 g (67% of theory) of a white, crystalline product of melting point 41-43 aq. Are obtained. NCO Titration: calculated 2.30 mVal / g, found 2.36 mVal / g.

Example A3: Obtaining In the apparatus described in Example Al, 1.74 g (0.01 mol) of toluylene-2,4-diisocyanate (TDI) are dissolved in 20 ml of dichloromethane with 2.24 g (0.01 mol) of Darocure 2959 and reacted in 60 ml. of dry dichloromethane. The reaction mixture, without adding any catalyst, is stirred for 48 hours at room temperature and i hour at 40 ° C., until no more unreacted Darocure 2959 can be found in the thin layer chromatogram. The product is isolated by precipitating the reaction solution in 180 ml of dry petroleum ether (bp 40-60 ° C) and then recrystallizing twice from dichloromethane / petroleum ether 1: 3. A white, crystalline product of melting point 124-1258C is obtained. Yield 17.2g, which corresponds to 87% of the theory. OCN titration: calculated 2.50 mVal / g, found 2.39 mVal / g.

Example A4: Obtaining the following compound: Into a 100 ml flask with reflux condenser, thermometer, stirrer and nitrogen introduction tube, 2.92 g (10 mmol) of 2-ethyl-2-dimethylamino-1- (4- (2-hydroxyethoxy) -phenyl) are dissolved. ) -pent-4-en-l-one in 30 ml of dry methylene chloride and mixed with 2.22 g (10 mmol) I PDI dissolved in 30 ml of dry methylene chloride. To this, 2 mg of the DBTDL catalyst is added and the mixture is stirred for 72 hours at room temperature. The course of the reaction is followed with DC (eluent: toluene / acetone 6: 1). Then the reaction solution is mixed in water. The organic phase is separated and washed twice more with water. The organic phase is dried through MgSO 4 and concentrated in the rotary evaporator. The remaining residue is cleaned by column chromatography (toluene / acetone 6: 1). 3.4 g (66%) of a yellow oil are obtained. The structure is verified with proton NMR, IR and elemental analysis. Obtaining 2-ethyl-2-dimethylamino-1- (4- (2-hydroxyethoxy) phenyl) -pent-4-en-l-one it is carried out with the support of the synthesis described in EP-A-284, 561, with a quantitative yield. Yellowish crystals of melting point 80-82ac are obtained.

Example A5: Analogously to Example A4, the following isocyanate is obtained from 1.17 g (4 mmol) of l- (4- (2-hydroxyethoxy) phenyl) -2-methyl-2-morpholino-propan-l- ona, 0.7 g (4 mmol) of 2,4-TDI with DBTDL as a catalyst in methylene chloride. After adding 50 ml of ether and 200 ml of petroleum ether to the reaction mixture, the target compound is precipitated in crystalline form. This is filtered, washed with petroleum ether and then dried under vacuum. The compound reproduced below is obtained, with a melting point of 97-102ac.

Obtaining 1- (4- (2-hydroxyethoxy) f-enyl) -2-methyl-2-morpholino-propan-l-one it is carried out based on the synthesis described in EP-A-088,050.

Example A6: Analogously to Example A4, the following compound Am is obtained. Analogously to Example A4, the following compound is obtained: Examples B: Example Bl: 3 g (6.72 x 10 - ~ 3 J mol) of the photoinitiator obtained in example Al and 7.5 g (6.72 x 10 mol) of freshly distilled N-vinylpyrrolidone are dissolved in 60 ml of dry acetone and placed in a DEMA-3H photoreactor, which features a high-pressure Hg immersion lamp. By evacuation and aerated three times with dry nitrogen, the solution in the reactor is then released from the oxygen. The solution thus prepared, under dry nitrogen as well as under vigorous stirring, is irradiated for 100 minutes with UV light. At this time a slightly yellowish solid is deposited on the walls of the vessel, which could be dissolved with dry DMSO, after having removed the acetone reaction solution. By precipitation of both solutions thus obtained in 10 times the volume of non-solvent (dry), two solids are obtained, product A and product B.

Product A: Solution in 50 ml DMSO precipitated in 500 ml of dry diethyl ether, quantity: 1.4 g of white powder, after drying in high vacuum through P05, 14 hours, content in OCN: 0.041 mVal / g, determined by titration , IR spectrum: clear OCN absorption band at 2145 cm ", molecular weight: calculated from the OCN content: Mn approximately 25'000 D, measured (vapor pressure osmometry) in DMF: Mn approximately 27 '600 + / - 3 '100 D, average degree of polymerization: calculated from molecular weight: DPn approximately 220.

Product B: Reaction solution in 50 ml of acetone precipitated in 500 ml of dry diethyl ether, amount: 1.6 g of white powder, OCN content: 0.191 mVal / g, IR spectrum: strong OCN absorption band at 2145 cm ~, weight molecular: calculated from the OCN content: Mn approximately 5 '260 D, measured (vapor pressure osmometry) in DMF: Mn approximately 5' 370 +/- 400 D, average degree of polymerization: DPn approximately 44.

Example B2: As described in Example Bl, 3 g of the functional photoinitiator and 7.5 g of N-vinylpyrrolidone are reacted with each other under analogous reaction conditions. However, first only 30 ml of acetone are first placed in the photoreactor. Then the solution of 3 g of photoinitiator in 20 ml of acetone as well as the solution of 7.5 g of NVP in 20 ml of acetone are added slowly by dripping, simultaneously for 5 hours under permanent UV irradiation. After another half hour of irradiation time, the product of the reaction, which in this case remained completely as a solution, is isolated by precipitation in 700 ml of dry diethyl ether and dried. Yield 5.63 (53.6% of theory), content in OCN: 0.266 mVal / g, molecular weight: Mn approximately 3 '760.

Examples B3 to B10: Analogously to Example B2, a series of other hydrophilic and hydrophobic vinyl monomers are transformed into OCN-functional phototelóeros: Example B3: 3g of photoinitiator of example Al, Vinyl monomer: 10 g of DMA Content in OCN (mVal / g): 0.236 Mn: 4'240 Example B4: 3 g of photoinitiator of Example A2, Vinyl monomer: 12 g of diethylene glycol monomethyl ether and letermet acrylate Content in OCN (mVal / g): 0.122 Mn: 8'200 Example B5: 3 g of photoinitiator of Example A3, Vinyl monomer: 12 g of 2- (N, N-dimethylaminoethyl) methacrylate Content in OCN (mVal / g): 0.568 Mn: 1'760 Example B6: 3g of photoinitiator of Example A4, Vinyl Monomer: 17g of TRIS Content in OCN (mVal / g): 0.444 Mn: 2'250 Example B7: 3g of photoinitiator from example Al, Vinyl monomer: 10g of MMA Content in OCN (mVal / g): 0.068 Mn: 14'700 Example B8: 3 g of photoinitiator of example Al, Vinyl monomer: 22 g of 2,2,3,4,4, 4-hexaf luorbutylmethacrylate Content in OCN (mVal / g): 0.30 Mn: 3'340 Example B9: 3g of photoinitiator of example Al, Vinyl monomer: 20 g of 3- (penta ethyldisilox?) Propyl methacrylate Content in OCN (mVal / g): 0.140 Mn: 7'160 Example B10: 3g of photoinitiator from example Al, Vinyl monomer: 15g of glycidylmethacrylate Content in OCN (mVal / g): 0.089 Mn: 11'200 Examples C: Surface modification by OCN phototelomers in films and flat substrates Examples C1-C4: Films of various polymeric materials, which have reactive groups, are wetted on the surface with the phototelomer solution obtained according to example Bl, in a solvent suitable (concentration approximately 20% by weight), used as a dip, spray and brush application technique. The films thus treated are heated under dry nitrogen for 24 hours at 60 ° C and then released by washing with acetone from the untransformed phototelomer. After drying under exclusion of light, the films are analyzed by the FTIR microscope.

Example Mn Film Solvent IR Bands (cm) polymer Cl Polyvinyl alcohol approx. 70O00 DMSO PVP: 1660 (OO) 1440-1470 (C-H) 12T0 (C-N) C2 Chitosan approx. 145O00 DMSO PVP: 1660 (C == 0) 1440-1470 (C-H) 1280 (C-N) C3 Collagen approx. 80O00 DMSO PVP: 1660 (OO) 1440-1470 (C-H) 1280 (C-N) C4 Polyvinyl alcohol - MEK + l% DMSO PVP: 1660 (OO) crosslinked with 1 * 1440-1470 (C-H) of TMDI • 1280 (C-N) TMDI = Trimethylhexandiisocyanate, MEK = Methyl ethyl ketone Example C5: The flat plates (5 x 5 x 0.5 cm) of a) polyurethane, b) glass and c) aluminum coated with capton-polyimide are subjected to a usual treatment with an argon plasma in the presence of n-heptylamine. By means of this procedure a film of some nanometers in thickness is created in the substrates, which presents reactive amino groups. As described in examples Cl to C4, the plates thus treated previously are treated with a solution of product A of example Bl in DMSO. In this way a hydrophilic coating of polyvinylpyrrolidone is created on the plates, which has a brush structure. The following contact angles are measured on these plates with a Krüss G40 instrument: Just a while to!; - -. R s t Angle of c_ "- a ct _ s i n t r at a m e [°] 7 R" Angle of contact with t ratami ent [°] 3fa Example C6: (plasma treated silicone film) A silicone rubber film, which was created by UV tempering of PS-2067 (Petrarch Hüls America Inc., Bristol USA) which was applied as a coating on a Folanorm film ( Folex, Zurich, Switzerland), heated to 80ac and 10 Torr. Next, the film is placed in a common commercial plasma reactor of a radio frequency of 13.6 megahertz, and the system is evacuated at 0.1 mbar. At this pressure, an oxygen flow of 10 standard cubic centimeters and 40 Watt electrical efficiency, the film is subjected to 30 seconds to an oxygen plasma. By turning off the plasma and aerating the reactor, the film is stored in the air.

Example C7: polybutadiene film, treated with plasma) On a Folanorm carrier sheet, of a THF solution of poly-l, 2-butadiene (syndiotactic polybutadiene, Polysciences Inc., product 16317), a film is poured under a nitrogen atmosphere. 0.5 mm thick. The film, as described in example C6, is subjected to oxygen plasma treatment.

Example C8 From a mixture of 92% of 2-hydroxyethylmethacrylate (HEMA), 7.7% of ethylene glycol dimethacrylate and 0.3% of Irgacure * 184 (0.3%) a film is poured onto a Folanorm carrier sheet and is usually tempered by UV irradiation.

Example C9: A solution of 10% DMSO of 99% polyvinylalcohol (PVA), Mn 72 '000 (Fluka AG, Switzerland) and 1% isophorone diisocyanate (Aldrich) is applied by brush on Folanorm a film and warmed by heating from two hours to 702C, at the end at 0.01 Torr. The film is released by washing with THF of the DMSO as well as of the excess IPDI and then, for 6 hours at 80ac and 0.001 Torr of the remaining solvent.

Examples CIO to C13: The following table shows the contact angles (Krüss G40) of polymer films as described in Examples C6 to C9, which were treated according to the method reproduced in example Cl with the photonomer NVP OCN-functional obtained in example B2.

Example Material (film) Angle cmtactc [°] iin t tan? »Nf n tia amient CÍO Siliror (Co) l ?? .4 r .5 Cll P_l? Butad? En-. IC7) 7. £ .3. _ C12 P: l? -HEMA ¡C? "6.4? -. £; 13 PVA (CO, 4" .1 &l '; E Example C14: Hi-drogel soft lenses (STD-CibasoftTM, Tefilcon, CIBA Vision, Atlanta, USA) released by salt wash and Freeze-dried, based on cross-linked poly-HEMA, are treated for 12 hours with a solution of a phototelomer (1 g in 10 ml of dry DMSO), which contains 10 mg of dibutyltin dilaurate as a catalyst. are described in the examples Bl (A), Bl (B), B3, B4 and B5, after which the lenses are carefully washed with acetone and water and dried in vacuo at 0.1 mbar The following table shows the contact angles of the lenses treated in this way and then autoclaved (1202C, 30 minutes) in physiological salt solution with phosphate buffer (pH 7.4) The data show that a hydrophilic surface was created on the lenses by the treatment .

Use of Contact Angle Phototelomer eg without treatment a) Bl! A ß 5 ^ b) Bl B? 46 c) B3 78 42 d) B4 78 36 e) B5 78 50 Example C15: Various contact lenses are conventionally subjected to a plasma treatment, in the presence of ammonia or n-heptylamine gas, to create reactive amino groups on the surface. The lenses thus treated previously are then treated, as described in example Cl, with a solution of the PVP phototelomer obtained in example B2. The contact angles (Instrument Krüss G40) shown in the following table show that contact lenses treated and then autoclaved have a hydrophilic surface.

Example Plasma gas material Angle of contact ["1 lens if treated"] with contact treatment a) Tefillon Ammonia - 32 b) Silicon * Amoniac: 104 52 c) Silicon * Heptilan na 104 48 d) Atlafilcon A Heptylamine - 37 * The silicone material used is a copolymer composed of 15% by weight of methyl methacrylate, 15% by weight of TRIS and 70% by weight of a polydimethylsiloxane macromer, with an average molecular weight Mn of ca. 4'000, which has two terminal hydroxybutyl groups, which were respectively terminated with isocyanatoethyl methacrylate.

Examples D: Example DI: Obtaining a comb polymer using an OCN-functional phototelomer In a 250 ml flask with reflux condenser, thermometer, agitator and nitrogen inlet tube, under dry nitrogen, a solution of 11.78 g (0.00224 mol) of the finished poly (N-vinylpyrrolidone) B OCN telomer is dissolved., described in Example Bl, in 100 ml of dry DMSO with 4.37 g of aminoalkyl-polydimethylsiloxane (0.515 mVal NH2 / g, Petrarch PS 813®: Mn about 3 '000, b = 3, a + c = 37) and it is reacted in 50 ml of dry dichloromethane. The reaction mixture is stirred for 2 hours at room temperature and then heated 1 hour at 402 ° C. After evaporation of the dichloromethane in the rotary evaporator, the viscous DMSO solution of the amphiphilic comb polymer PDMS-Poli-NVP is isolated by precipitation in 1000 ml of dry diethyl ether. After removing the solvent residues at the end of the high vacuum at 402 ° C and 4 ° Torr, 15.9 g (98% of the theory) of a viscous colorless product having surface activity characteristics is obtained. shows no OCN absorption.

Examples D2-D6: In a manner analogous to the DI example, other block and comb polymers are obtained from the described OCN-functional phototelomers, by transformation with aminofunctional macromers. The results are summarized in the following table, meaning in the structural formulas "Zx" the respective radical of the phototelomer bound through a urea bridge. The index "x" expresses the respective example number of the phototelomer of the series of examples B.

Table: Example Compound Macromer according to Structure Rendí ™; to unofficial to the e]. B1-B10 'Product) D2 X-22-lolc 12.63 g E1A at 19.e ^ (Shin Etsu, JP) (3.36 mmol) (36r 7.8g (0.43 mVal NH2 / g) M about 4' 60C D3 Jeffarnin® T 403 14.3 g 36 or 17.0 g (Texaco, USA) '6.36 mmcl) l 39. * 2.8g (ó.38 mVal NH: 3 i D4 Jeffamir, ® D20ÜC * • ¿, 3 £ - - l?. J ( Texaco, USA) < - ° ™ oi '! 9d * 4.0g (1 mVal NH: / g) D5 KF-6003 9.55g B3 i 13.? (S in Etsu, JF) (2.25 nmol) (93 * D6 X-22-161B, Og B5 e 6.35j (S in Etsu, JF (2.29 mmol) (95.44 '3.23g (0.693 mVal M ap ox, 2' 9uC c _ Zg - NH CH CH2- (O CH2 CH-) NH- Z ^ CH, CH, x: y = 27: 1 _ Zg- NH - (CHgJg- NH Zg wherein Zl, Z3, Z5, Z6 and Z8 mean the corresponding radicals of Examples Bl, B3, B5, B6 and B8.

EXAMPLE El: (Obtaining a polymerizable macromonomer) Using the reaction conditions indicated in example DI, 37.6 g (0.01 mol) of the photonomer PVP OCN-fnal described in Example B2 are reacted with 1.31 g of 2-hydroxyethylmethacrylate ( HEMA) in 250 ml of dry DMSO, adding 10 mg of dibutyltin dilaurate as a catalyst. After precipitation in dry diethyl ether and drying at 10 ° Torr, 38.8 g of a white, powder-like product are obtained.

Claims (15)

NOVELTY OF THE INVENTION Having described the foregoing invention, the content of the following is claimed as property: CLAIMS

1. Vinyl telomers of the formula I, 0 = C = N-PI * _ (_ A-) p-Ra (I) wherein Pl * represents a bivalent radical of a photoinitiator, A represents a substituted bivalent substituted 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the double bond of the vinyl with a single bond, each Ra, independently from yes, it represents a univalent group, which is suitable to serve as a chain switch of a polymerization, and p represents an integer from 3 to 500.

2. A process for obtaining a compound of the formula I according to claim 1 , characterized in that a photoinitiator of formula B, OCN-PI * -Raa (B) is reacted wherein Pl * is defined as indicated in claim 1 and Raa represents the part of a photoinitiator which, in a dissociation thereof, forms the less reactive radical, with a vinyl monomer in a manner known per se.

3. A process according to claim 2, characterized in that the reaction takes place under the effect of UV irradiation.

4. A method according to claim 3, characterized in that, during UV irradiation, a solution containing a photoinitiator of the formula B and a second solution containing a vinyl monomer are dosed simultaneously.

5. Polymerizable compounds of formula C, O Mono _R? -C-NH-PI * -μV -Ra (C) wherein mono represents a univalent radical of a vinyl monomer, of which the Rx-H group is separated, Rx, independently of each other, represents a bond, -0- "- NRN- or -S-, wherein RN represents hydrogen or lower alkyl, Pl * represents a bivalent radical of a photoinitiator, A represents a bivalent, substituted 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the vinyl double bond with a single bond, each Ra , independently of each other, represents a univalent group, which is suitable to serve as chain switch of a polymerization, and p represents an integer from 3 to 500.

6. A process for obtaining a compound of formula C, according to to claim 5, characterized in that a vinyl telomer of the formula I, defined as in claim 1, is reacted in a manner known per se with a vinyl monomer, which contains at least one Rx-H group, wherein R x represents -O-, -NRN- or -S-, wherein RN represents hydrogen or lower alkyl.

7. Block copolymers which are not crosslinked, but may be crosslinkable, of the formula D, O Macro -Ll C-NH-PI * - A-Ral () m where macro represents a m-valent radical of a macromer, of which the number of m groups Rx-H is separated, Rx, independently of each other, represents a bond, -O-, -NRN- or -S-, in where RN represents hydrogen or lower alkyl, Pl * represents a bivalent radical of a photoinitiator, A represents a bivalent, substituted 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the vinyl double bond with a bond simple, each Ra, independently of each other, represents a univalent group, which is suitable to serve as a chain switch of a polymerization, p represents an integer from 3 to 500, and represents an integer from 1 to 100.

8. A process for obtaining a compound of the formula D, according to claim 7, characterized in that a macromer of the formula A is reacted in a manner known per se: Macro- (RxH) m (A) wherein Macro, Rx and m are defined as in claim 7, without taking into account that Rx is other than a bond, with a vinyl telomer of the formula I, 0 = C = N-PI * _ (_ A-) p-Ra (I) wherein Pl *, A, Ra and p are defined as in claim 7.

9. Polymers, in which they are polymerization products of a mixture capable of polymerization, which contains the following components: a) a compound capable of polymerization of formula C as defined in claim 5, b) optionally, a copolymerizable vinyl monomer, c) a copolymerizable crosslinker.

10. Polymers, which are polymerization products of a mixture capable of polymerization, containing the following components: aa) a compound capable of polymerization of formula D as defined in claim 7, wherein in the component - (A) p- is a reactive group, bb) optionally a copolymerizable vinyl monomer, ce) a crosslinker which is coreactive with the reactive group in the component - (A) p- of the compound of the formula D

11. A process for obtaining a polymer according to claim 9 or 10, characterized in that components a), b) and c), defined as in claim 9, or components aa), bb) and ce), defined as in claim 10, they are polymerized in a manner known per se.

12. A molded body that basically contains a polymer according to claim 9 or 10.

13. A molded body according to claim 12, in which it is a contact lens.

14. The use of a vinyl telomer of formula I, defined as in claim 1, for coating surfaces.

15. The use according to claim 14, characterized in that, in the case of surfaces, it is the contact lens surfaces. SUMMARY OF THE INVENTION The invention relates to novel NCO-terminal vinyl telomers, which are particularly suitable for the modification of surfaces and as a coating material, but also for the preparation of polymerizable compounds or block copolymers, which can be converted into polymers, or, in molded bodies, particularly contact lenses. In the case of the OCN-terminal vinyl telomers, these are compounds of the formula I, 0 = C = N-PI * _ (_ A-) p-Ra (!) wherein Pl * represents a bivalent radical of a photoinitiator, A represents a substituted bivalent substituted 1,2-ethylene radical, which is derived from a copolymerizable vinyl monomer by replacing the double bond of the vinyl with a single bond, each Ra, independently from yes, it represents a univalent group, which is suitable to serve as a chain switch of a polymerization, and p represents an integer from 3 to 500. The OCN-functional vinyl telomers find application in obtaining macromers as well as copolymers of block, comb, star and graft, which are preferred for the manufacture of contact lenses. Furthermore, these telomeres are used to coat surfaces of different types, particularly contact lens surfaces.