Title:
Bottle-brush type coatings with entangled hydrophilic polymer
Document Type and Number:
Kind Code:
A1

Abstract:
The invention relates to a process for coating a material surface comprising the steps of:

(a) providing an inorganic or organic bulk material having covalently bound to its surface initiator moieties for radical polymerization;

(b) graft polymerizing a hydrophilic ethylenically unsaturated macromonomer from the bulk material surface in the presence of a biocompatible hydrophilic polymer being devoid of polymerizable ethylenically unsaturated groups and thereby entrapping said hydrophilic polymer within the polymer matrix formed by the polymerization of the macromonomer.

Composite materials obtainable according to the process of the invention have desirable characteristics regarding adherence to the substrate, durability, hydrophilicity, wettability, biocompatibility and permeability and are thus useful for the manufacture of biomedical articles such as ophthalmic devices.

Inventors:
Chabrecek, Peter (Riehen, CH)
Leukel, Jorg (Freiburg, DE)
Lohmann, Dieter (Munchenstein, CH)
Application Number:
10/142300
Publication Date:
01/09/2003
Filing Date:
05/09/2002
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Referenced by:
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Primary Class:
427/2.100
Other Classes:
427/553, 427/558
International Classes:
(IPC1-7): A61L002/00; B05D003/06
Attorney, Agent or Firm:
Novartis Corporation, Thomas Hoxie (PATENT AND TRADEMARK DEPT, SUMMIT, NJ, 079011027)
Claims:
1. A process for coating a biomedical device, which comprises: (a) providing an inorganic or organic bulk material having covalently bound to its surface initiator moieties for radical polymerization; (b) graft polymerizing a hydrophilic ethylenically unsaturated macromonomer from the bulk material surface in the presence of a biocompatible hydrophilic polymer being devoid of polymerizable ethylenically unsaturated groups and thereby entrapping said hydrophilic polymer within the polymer matrix formed by the polymerization of the macromonomer.

2. A process according to claim 1, wherein the material surface is the surface of a biomedical device, particularly a contact lens, intraocular lens or artificial cornea.

3. A process according to claim 1 or 2, wherein the attachment of the initiator moieties to the bulk material comprises: (a) providing a bulk material surface with H-active groups; (b) reacting the bulk material surface with a functional polymerization initiator having a functional group that is co-reactive to said H-active groups.

4. A process according to claim 1 or 2, wherein the attachment of the initiator moieties to the bulk material comprises: (a) reacting the material surface with a compound of formula 22embedded image wherein R29 is C1-C4-alkyl, C1-C4-alkoxy, hydroxy, sulfo, nitro, trifluoromethyl or halogen, g is an integer from 0 to 2, L1 is a group, which functions as a triggerable precursor for carbene or nitrene formation, L2 is amino, C1-C4-alkylamino, hydroxy, glycidyl, carboxy or a derivative thereof, isocyanato or isothiocyanato, or is a radical of formula —[L3]h—(spacer)—L2′ (1a) L2′ is amino, C1-C4-alkylamino, hydroxy, carboxy or a derivative thereof, isocyanato, isothiocyanato, —O-glycidyl or —O—C(O)—(CH2)h1—X2, wherein h1 is from 1 to 4 and X2 is carboxy or a derivative thereof, L3 is —NH—, —NC1—C6-alkyl-, —O—, —C(O)O—, —C(O)NH—, —NHC(O)NH—, —NHC(O)O— or —OC(O)NH—; (spacer) is linear or branched C1-C200-alkylene which may be substituted by hydroxy and/or interrupted by —O— except for C1-alkyl, or is C3-C8-cycloalkylene, C3-C8-cycloalkylene-C1-C6-alkylene, C3-C8-cycloalkylene-C1-C2-alkylene-C3-C8-cycloalkylene or C1-C6-alkylene-C3-C8-cycloalkylene-C1-C6-alkylene; and h is the number 0 or 1; (b) reacting the so modified surface with a functional polymerization initiator having a functional group that is co-reactive to L2 or L2′.

5. A process according to any one of claims 1, 2 or 4, wherein step (a) comprises applying the compound of formula (1) to the material surface and fixing said compound of formula (1) onto the material surface using radiation, in particular UV or visible light.

6. A process according to any one of claims 1, 2, 4 and 5, wherein L1 is the radical of formula 23embedded image g is 0, and L2 is carboxy or a derivative thereof or is a radical of formula —L3—(spacer)—L2′, wherein L3 is —C(O)O— or —C(O)NH—, (spacer) is linear C2-C12-alkylene or —(C2-C3-alkylene)—O—(CH2CH2O)18-160—(C2-C3-alkylene)—, and L2′ is carboxy, a carboxy derivative or a radical —O—C(O)—(CH2)2—X2, wherein X2 is carboxy or a carboxy derivative.

7. A process according to any one of claims 1, 2, 4, 5 and 6, wherein L1 is the azide radical —N3, g is 0 or 1, R29 is methyl, methoxy, hydroxy or nitro, and L2 is amino, carboxy, a carboxy derivative, isocyanato, isothiocyanato or a radical of formula —L3—(spacer)—L2′, wherein L3 is —NH— —C(O)O— or —C(O)NH—, (spacer) is linear C2-C12-alkylene or —(C2-C3-alkylene)—O—(CH2CH2O)18-160—(C2-C3-alkylene)—, and L2′ is carboxy, a carboxy derivative or a radical —O—C(O)—(CH2)2—X2, wherein X2 is carboxy or a carboxy derivative.

8. A process according to claims 3 or 4, wherein the functional polymerization initiator is a photoinitiator of formula 24embedded image wherein Z is bivalent —O—, —NH— or —NR12—; Z1 is —O—, —O—(O)C—, —C(O)—O— or —O—C(O)—O—; R3 is H, C1-C12-alkyl, C1-C12-alkoxy or N—C1- C12-alkylamino; R4 and R5 are each independently of the other H, linear or branched C1-C8-alkyl, C1-C8-hydroxyalkyl or C6-C10-aryl, or the groups R4—(O)b1— and R4—(O)b2— together are —(CH2)c— wherein c is an integer from 3 to 5, or the groups R4—(O)b1—, R4—(O)b2— and R5—(O1)b3— together are a radical of the formula 25embedded image R2 is a direct bond or linear or branched C1-C8-alkylene that is unsubstituted or substituted by —OH and/or is uninterrupted or interrupted by one or more groups —O—, —O—C(O)— or —O—C(O)—O—; R1 is branched C3-C18-alkylene, unsubstituted or C1-C4-alkyl— or C1-C4-alkoxy-substituted C6-C10-arylene, or unsubstituted or C1-C4-alkyl- or C1-C4-alkoxy-substituted C7-C18-aralkylene, unsubstituted or C1-C4-alkyl- or C1-C4-alkoxy-substituted C3-C8-cycloalkylene, unsubstituted or C1-C4-alkyl- or C1-C4-alkoxy-substituted C3-C8-cyclo-alkylene-CyH2y— or unsubstituted or C1-C4-alkyl- or C1-C4-alkoxy-substituted —CyH2y—(C3-C8-cycloalkylene)—CyH2y— wherein y is an integer from 1 to 6; R6 independently has the same definitions as R1 or is linear C3-C18-alkylene; R12 is linear or branched C1-C6-alkyl; T is bivalent —O—, —NH—, —S—, C1-C8-alkylene or 26embedded image Z2 is a direct bond or —O—(CH2)d— or —(OCH2CH2)d— wherein d is an integer from 1 to 6 and the terminal CH2 group of which is each linked to the adjacent T in formula (3c); R8 is linear or branched C1-C8-alkyl, C2-C8-alkenyl or C6-C10-aryl-C1-C8-alkyl; R9 independently of R8 has the same definitions as R8 or is C6-C10-aryl, or R8 and R9 together are —(CH2)e— wherein e is an integer from 2 to 6; R10 and R11 are each independently of the other linear or branched C1-C8-alkyl that may be substituted by C1-C4-alkoxy, or C6-C10-aryl-C1-C8-alkyl or C2-C8-alkenyl; or R10 and R11 together are —(CH2)f1—Z3—(CH2)f2— wherein Z3 is a direct bond, —O—, —S— or —NR7—, and R7 is H or C1-C8-alkyl and f1 and f2 are each independently of the other an integer from 2 to 4; R13 and R13′ are each independently of the other H, C1-C8-alkyl, C3-C8-cycloalkyl, benzyl or phenyl; and a, a1, b1, b2 and b3 are each independently of the other 0 or 1; subject to the provisos that b1 and b2 are each 0 when R15 is H; that the total of (b1+b2+b3) is not exceeding 2; and that a is 0 when R12 is a direct bond.

9. A process according to any one of claims 1 to 8, wherein a macromonomer of formula 27embedded image is applied in step (b), wherein R32 is hydrogen, C1-C6-alkyl or a radical —COOR′; R, R′ and R32′ are each independently of the other hydrogen or C1-C6-alkyl; A is a direct bond or is a radical of formula —C(O)—(A1)n—X— (5a) or —(A2)m—NH—C(O)—X— (5b) or —(A2)m—X—C(O)— (5c) or —C(O)—NH—C(O)—X— (5d) or —C(O)—X1—(alk*)—X—C(O)— (5e) or A and R32, together with the adjacent double bond, are a radical of formula 28embedded image A1 is —O—C2-C12-alkylene which is unsubstituted or substituted by hydroxy, or is —O—C2-C12-alkylene—NH—C(O)— or —O—C2-C12-alkylene-O—C(O)—NH—R33—NH—C(O)— or —NH—(Alk*)—C(O)—, wherein (Alk*) is C1-C6-alkylene and R33 is linear or branched C1-C18-alkylene or unsubstituted or C1-C4-alkyl- or C1-C4-alkoxy-substituted C6-C10-arylene, C7-C18-aralkylene, C6-C10-arylene-C1-C2-alkylene-C6-C10-arylene, C3-C8-cycloalkylene, C3-C8-cycloalkylene-C1-C6-alkylene, C3-C8-cycloalkylene-C1-C2-alkylene-C3-C8-cycloalkylene or C1-C6-alkylene-C3-C8-cycloalkylene-C1-C6-alkylene; A2 is C1-C8-alkylene; phenylene or benzylene; m and n are each independently of the other the number 0 or 1; X, X1 and X′ are each independently of the other a bivalent group —O— or —NR″, wherein R″ is hydrogen or C1-C6-alkyl; (alk*) is C2-C12-alkylene; and (oligomer) denotes (i) the radical of a telomer of formula 29embedded image wherein (alk) is C2-C12-alkylene, Q is a monovalent group that is suitable to act as a polymerization chain-reaction terminator, p and q are each independently of another an integer from 0 to 350, wherein the total of (p+q) is an integer from 2 to 350, and B and B′ are each independently of the other a 1,2-ethylene radical derivable from a copolymerizable vinyl monomer by replacing the vinylic double bond by a single bond, at least one of the radicals B and B′ being substituted by a hydrophilic substituent; or (ii) the radical of an oligomer of the formula 30embedded image wherein R19 is hydrogen or unsubstituted or hydroxy-substituted C1-C12-alkyl, u is an integer from 2 to 250 and Q′ is a radical of a polymerization initiator; or (iii) the radical of formula 31embedded image wherein R19, X and u are as defined above, or (iv) the radical of an oligomer of formula 32embedded image wherein R20 and R20′ are each independently C1-C4-alkyl, An−is an anion, v is an integer from 2 to 250, and Q″ is a monovalent group that is suitable to act as a polymerization chain-reaction terminator; or (v) the radical of an oligopeptide of formula —(CHR21—C(O)—NH)t—CHR21—COOH (6d) or —CHR21—(NH—C(O)—CHR21)t—NH2 (6d′) wherein R21 is hydrogen or C1-C4-alkyl which is unsubstituted or substituted by hydroxy, carboxy, carbamoyl, amino, phenyl, o- , m-0 or p-hydroxyphenyl, imidazolyl, indolyl or a radical —NH—C(═NH)—NH2 and t is an integer from 2 to 250, or the radical of an oligopeptide based on proline or hydroxyproline; or (vi) the radical of a polyalkylene oxide of formula —(alk**—O)z—[CH2—CH2—O]r—[CH2—CH(CH3)—O]s—R34 (6e) wherein R34 is hydrogen or C1-C24-alkyl, (alk**) is C2-C4-alkylene, z is 0 or 1, r and s are each independently an integer from 0 to 250 and the total of (r+s) is from 2 to 250; or (vii) the radical of an oligosaccharide; subject to the provisos that A is not a direct bond if (oligomer) is a radical of formula (6a); A is a radical of formula (5a), (5b) or (5d) or A and R32, together with the adjacent double bond, are a radical of formula (5f) if (oligomer) is a radical of formula (6b), (6c), (6d) or (6e) or is the radical of an oligosaccharide; A is a direct bond if (oligomer) is a radical of formula (6b′); and A is a radical of formula (5c) or (5e) if (oligomer) is a radical of formula (6d′).

10. A process according to claim 9, wherein R is hydrogen or methyl, R32 and R32′ are each hydrogen, A is a radical of the formula (5a) and (oligomer) is a radical of formula (6a).

11. A process according to claim 9 or 10, wherein (oligomer) is a radical of formula 33embedded image wherein (alk) is C2-C4-alkylene, R25 and R25′ are each independently hydrogen or methyl, Q is a monovalent group that is suitable to act as a polymerization chain-reaction terminator, p and q are each independently an integer from 0 to 100 wherein the total of (p+q) is an integer from 5 to 100, and R26 and R26′, are each independently a radical —COOY, wherein Y is C1-C2-alkyl, C2-C3-alkyl, which is substituted by hydroxy, amino or N,N-di-C1-C2-alkyl-amino, or is a radical -C2-C4-alkylene-NH—C(O)—O—G wherein —Q—G is the radical of trehalose; a radical —CO—NY1Y2, wherein Y1 and Y2 are each independently of the other hydrogen or C1-C2-alkyl which is unsubstituted or substituted by hydroxy, or Y1 and Y2 together with the adjacent N-atom form a N—C1-C2-alkylpiperazino or morpholino ring; a heterocyclic radical selected from the group consisting of N-pyrrolidonyl, 2- or 4-pyridinyl, 2-methylpyridin-5-yl, 2-3- oder 4-hydroxypyridinyl, N-ε-caprolactamyl, N-imidazolyl, 2-methylimidazol-1-yl, N-morpholinyl and 4-N-methylpiperazin-1-yl; —COOH; —SO3H; o-, m- or p-sulfophenyl; o-, m- or p-sulfomethylphenyl; a radical —CONY5Y6 wherein Y5 is C2-C4-alkyl substituted by sulfo, and Y6 is hydrogen; C1-C4-alkyl which is substituted by —NR23R23′R23″+An− wherein R23, R23′ and R23″ are each independently of another hydrogen or C1-C4-alkyl and An− is an anion; a radical —C(O)OY7 wherein Y7 is C2-C4-alkyl, which is substituted by —NR23R23′R23″+An− and is further unsubstituted or substituted by hydroxy, wherein R23, R23′, R23″ and +An− are as defined; and a radical —C(O)O—CH2—CH(OY8)—CH2—O—PO2−—(CH2)2—N(CH3)3+, wherein Y8 is hydrogen or the acyl radical of a higher fatty acid.

12. A process according to any one of claims 1 to 11, wherein in step (b) a macromonomer of formula 34embedded image is applied, wherein R is hydrogen or methyl, (alk) is C2-C4-alkylene, R25 is hydrogen or methyl, p is an integer of 5 to 50, Q is a monovalent group that is suitable to act as a polymerization chain-reaction terminator, and R26 is a radical —CONH2, —CON(CH3)2 or 35embedded image

13. A process according to any one of claims 1 to 12, wherein the biocompatible hydrophilic polymer applied in step (b) is selected from the group consisting of hyaluronic acid, chondriotin sulfate, heparin, dextran and mucin.

14. A process according to any one of claims 1 to 12, wherein the biocompatible hydrophilic polymer applied in step (b) is selected from the group consisting of carboxymethylcellulose, carboxyalkylchitin and carboxyalkylchitosan.

15. A process according to any one of claims 1 to 12, wherein the biocompatible hydrophilic polymer applied in step (b) is selected from the group consisting of a polyoxyalkylene amine, polyethylene glycol, poly-HEMA, a crosslinked polyacrylic acid based polymer, polyacrylamide, polyvinylpyrrolidone and polyvinyalcohol.

16. A process according to claim 1, wherein in step (b) an additional bioactive compound, for example, a polyquat, is added.

17. A composite material obtainable by the process of any one of claims 1 to 16.

18. A composite material according to claim 17, which is a biomedical device, preferably an ophthalmic device such as a contact lens, intraocular lens or artificial cornea.

19. Use of a composite material according to claim 17 for the manufacture of an ophthalmic device, particularly for the manufacture of a contact lens, intraocular lens or artificial cornea.

Description:
[0001] The present invention relates to a process for coating articles, wherein the coating comprises a polymer having desirable characteristics regarding adherence to the substrate, durability, softness, hydrophilicity, lubricity, wettability, biocompatibility and permeability. More particular, the present invention relates to a process for coating an article, such as a biomedical material or article, especially a contact lens including an extended-wear contact lens, wherein the coating is composed of at least two individual hydrophilic polymer components. One of those hydrophilic components comprises polymer chains which are covalently bound to the substrate, whereas the second hydrophilic polymer is not covalently bound neither to the surface of the substrate nor to the polymer chains, but is being entrapped with said polymer chains.

[0002] Processes for preparing hydrophilic polymeric coatings on an “inert” hydrophobic substrate have been disclosed in the prior art. For example, WO 99/57581 discloses to first of all providing the article surface with covalently bound photoinitiator molecules, coating the modified surface with a layer of a polymerizable macromonomer and then subjecting it to a heat or radiation treatment whereby the macromonomer is graft polymerized thus forming the novel article surface. The covalent binding of the photoinitiator molecules to the article surface is created by first subjecting the article surface to a plasma treatment thereby providing the surface with functional groups, and then reacting said functional groups with co-reactive groups of a functional photoinitiator.

[0003] Surprisingly, it now has been found that articles, particularly biomedical devices such as contact lenses, with an even improved wettability, water-retention ability and biocompatibility are obtained by first of all providing the bulk material surface with covalently bound photoinitiator molecules, followed by grafting a hydrophilic ethylenically unsaturated macromonomer from the bulk material surface in the presence of a biocompatible hydrophilic polymer being devoid of polymerizable ethylenically unsaturated groups and thereby entrapping said biocompatible hydrophilic polymer within the polymer matrix formed by the polymerization of the macromonomer.

[0004] By this process, the macromonomer forms “bottle-brush” type tethered “hairy” chains on the bulk material surface having entangled a biocompatible hydrophilic polymer thereby forming a kind of semi-interpenetrating network (s-IPN) with the polymer chains of the macro-monomer.

[0005] The present invention therefore in one aspect relates to a process for coating a material surface comprising the steps of:

[0006] (a) providing an inorganic or organic bulk material having covalently bound to its surface initiator moieties for radical polymerization;

[0007] (b) graft polymerizing a hydrophilic ethylenically unsaturated macromonomer from the bulk material surface in the presence of a biocompatible hydrophilic polymer being devoid of polymerizable ethylenically unsaturated groups and thereby entrapping said hydrophilic polymer within the polymer matrix formed by the polymerization of the macromonomer.

[0008] Suitable bulk materials to be coated according to the invention are, for example, quartz, ceramics, glasses, silicate minerals, silica gels, metals, metal oxides, carbon materials such as graphite or glassy carbon, natural or synthetic organic polymers, or laminates, composites or blends of said materials, in particular natural or synthetic organic polymers or modified biopolymers which are known in large number. Some examples of polymers are polyaddition and polycondensation polymers (polyurethanes, epoxy resins, polyethers, polyesters, polyamides and polyimides); vinyl polymers (polyacrylates, polymethacrylates, polyacrylamides, polymethacrylamides, polystyrene, polyethylene and halogenated derivatives thereof, polyvinyl acetate and polyacrylonitrile); or elastomers (silicones, polybutadiene and polyisoprene).

[0009] A preferred group of materials to be coated are those being conventionally used for the manufacture of biomedical devices, e.g. contact lenses, in particular contact lenses for extended wear, which are not hydrophilic per se. Such materials are known to the skilled artisan and may comprise for example polysiloxanes, perfluoroalkyl polyethers, fluorinated poly(meth)acrylates or equivalent fluorinated polymers derived e.g. from other polymerizable carboxylic acids, polyalkyl (meth)acrylates or equivalent alkylester polymers derived from other polymerizable carboxylic acids, or fluorinated polyolefines, such as fluorinated ethylene or propylene, for example tetrafluoroethylene, preferably in combination with specific dioxols, such as perfluoro-2,2-dimethyl-1,3-dioxol. Examples of suitable bulk materials are e.g. lotrafilcon A, neofocon, pasifocon, telefocon, silafocon, fluorsilfocon, paflufocon, elastofilcon, fluorofocon or teflon AF materials, such as teflon AF 1600 or teflon AF 2400 which are copolymers of about 63 to 73 mol % of perfluoro-2,2-dimethyl-1,3-dioxol and about 37 to 27 mol % of tetrafluoroethylene, or of about 80 to 90 mol % of perfluoro-2,2-dimethyl-1,3-dioxol and about 20 to 10 mol % of tetrafluoroethylene.

[0010] Another group of preferred materials to be coated are amphiphilic segmented copolymers comprising at least one hydrophobic segment and at least one hydrophilic segment, which are linked through a bond or a bridge member. Examples are silicone hydrogels, for example those disclosed in PCT applications WO 96/31792 and WO 97/49740.

[0011] A particular preferred group of materials to be coated comprises organic polymers selected from polyacrylates, polymethacrylates, polyacrylamides, poly(N,N-dimethylacrylamides), polymethacrylamides, polyvinyl acetates, polysiloxanes, perfluoroalkyl polyethers, fluorinated polyacrylates or -methacrylates and amphiphilic segmented copolymers comprising at least one hydrophobic segment, for example a polysiloxane or perfluoroalkyl polyether segment or a mixed polysiloxane/perfluoroalkyl polyether segment, and at least one hydrophilic segment, for example a polyoxazoline, poly(2-hydroxyethylmethacrylate), polyacrylamide, poly(N,N-dimethylacrylamide), polyvinylpyrrolidone polyacrylic or polymethacrylic acid segment or a copolymeric mixture of two or more of the underlying monomers.

[0012] The material to be coated may also be any blood-contacting material conventionally used for the manufacture of renal dialysis membranes, blood storage bags, pacemaker leads or vascular grafts. For example, the material to be modified on its surface may be a polyurethane, polydimethylsiloxane, polytetrafluoroethylene, polyvinylchloride, Dacron™ or Silastic™ type polymer, or a composite made therefrom.

[0013] The form of the material to be coated may vary within wide limits. Examples are particles, granules, capsules, fibres, tubes, films or membranes, preferably moldings of all kinds such as ophthalmic moldings, for example intraocular lenses, artificial cornea or in particular contact lenses.

[0014] The bonding of the photoinitiator moieties according to step (a) may be accomplished

[0015] (i) according to the methods described in WO 99/57581, where the surface of the bulk material is first of all subjected to a plasma treatment thereby introducing reactive groups at the surface of the surface, followed by reaction of said reactive groups with an initiator moiety bearing co-reactive functional groups, or

[0016] (ii) by reaction of certain hetero-bifunctional compounds at the surface of the bulk material said compounds having a first highly reactive functional group, which is able to react with the “inert” bulk material surface, and a second functional group for further covalent attachment of the initiator moieties.

[0017] Said hetero-bifunctional compound is, for example, a compound of formula 1 embedded image

[0018] wherein R 29 is C 1 -C 4 -alkyl, C 1 -C 4 -alkoxy, amino, hydroxy, sulfo, nitro, trifluoromethyl or halogen,

[0019] g is an integer from 0 to 2,

[0020] L 1 is a group, which functions as a triggerable precursor for carbene or nitrene formation,

[0021] L 2 is amino, C 1 -C 4 -alkylamino, hydroxy, glycidyl, carboxy or a derivative thereof, isocyanato or isothiocyanato, or is a radical of formula

—[L 3 ] h —(spacer)—L 2 ′ (1a)

[0022] wherein L 2 ′ is amino, C 1 -C 4 -alkylamino, hydroxy, carboxy or a derivative thereof, isocyanato, isothiocyanato, —O-glycidyl or —O—C(O)—(CH 2 ) h1 —X 2 , wherein h1 is from 1 to 4 and X 2 is carboxy or a derivative thereof,

[0023] L 3 is —NH—, —NC 1 —C 6 -alkyl-, —O—, —C(O)O—, —C(O)NH—, —NHC(O)NH—, —NHC(O)O— or —OC(O)NH—;

[0024] (spacer) is linear or branched C 1 -C 200 -alkylene which may be substituted by hydroxy and/or interrupted by —O— except for C 1 -alkyl, or is C 3 -C 8 -cycloalkylene, C 3 -C 8 -cycloalkylene-C 1 -C 6 -alkylene, C 3 -C 8 -cycloalkylene-C 1 -C 2 -alkylene-C 3 -C 8 -cycloalkylene or C 1 -C 6 -alkylene-C 3 -C 8 -cycloalkylene-C 1 -C 6 -alkylene; and

[0025] h is the number 0 or 1.

[0026] L 1 in formula (1) is, for example, a group of formula 2 embedded image

[0027] or

—N 3 (2b)

[0028] wherein R 30 is an electron-withdrawing substituent, for example fluorinated C 1 -C 6 -alkyl, such as a radical —C 2 F 5 or preferably a radical —CF 3 .

[0029] R 29 is preferably C 1 -C 4 -alkoxy, nitro, C 1 -C 4 -alkyl, hydroxy, amino or sulfo. The variable g is, for example, 1 or preferably 0.

[0030] One group of suitable radicals of formula (1) are those wherein L 1 is a group 3 embedded image

[0031] and g is 0. A further group of suitable radicals of formula (1) are those wherein L 1 is a group —N 3 , and g is 1 or preferably 0.

[0032] Throughout the application the terms carboxy derivative, a derivative of carboxy and the like are to be understood as meaning, for example, a lactone, a carboxylic acid anhydride, halide, amide or ester, for example —C(O)Cl, —C(O)NH 2 , —C(O)C 1 -C 6 -alkyl, —C(O)-phenyl or in particular an activated ester such as carboxy having been reacted with an activating agent, for example with N-hydroxy succinimide (NHS) or sulfo-N-hydroxy succinimide. A particularly preferred carboxy derivative is an activated ester of formula 4 embedded image

[0033] wherein Ka + is a cation, for example Na + or K + .

[0034] The term glycidyl means a radical 5 embedded image

[0035] The bivalent radicals L 3 are always to be understood that the left bond is directed to the phenyl ring and the right bond is directed to the (spacer) radical.

[0036] According to one preferred embodiment of the invention, L 2 is amino, isocyanato, isothiocyanato, carboxy or a derivative thereof, and in particular amino, isocyanato, carboxy, or an activated carboxylic acid ester as mentioned above.

[0037] L 3 in formula (1a) is preferably a bivalent group —O—, —NH—, —C(O)O—, —C(O)NH— or —NHC(O)NH—, and is most preferably a radical —NH—, —C(O)O— or —C(O)NH—. h is preferably the number 1.

[0038] (spacer) in formula (1a) is preferably linear or branched, optional hydroxy-substituted, C 1 -C 24 -alkylene or C 4 -C 160 -alkylene which is interrupted by —O—, more preferably C 1 -C, 6 -alkylene or C 8 -C 160 -alkylene which is interrupted by —O— and most preferably C 2 -C 12 -alkylene or —(alk′)—O—(CH 2 CH 2 O) 18-160 —(alk′)—, wherein (alk′) is, for example, C 1 -C 6 -alkylene, preferably C 1 -C 4 -alkylene, more preferably C 1 -C 3 -alkylene and in particular 1,2-ethylene. If (spacer) is a cycloalkylene or mixed alkylene/cycloalkylene radical, the meanings and preferences given below for R 33 apply.

[0039] L 2 ′ is preferably amino, isocyanato, carboxy, a carboxy derivative, or a radical —O—C(O)—(CH 2 ) 2 —X 2 , wherein X 2 is carboxy or a derivative thereof. Particularly preferred meanings of L 2 ′ are amino, carboxy and an activated carboxylic acid ester as mentioned above.

[0040] A further preferred embodiment of the invention relates to the use of a compound of formula (1), wherein L 2 is a radical of formula (1a), L 3 is —NH—, —C(O)O— or—C(O)NH—, h is 1, (spacer) is linear C 2 -C 12 -alkylene or —(C 2 -C 3 -alkylene)—O—(CH 2 CH 2 O) 18-160 —(C 2 -C 3 -alkylene)—, and L 2 ′ is carboxy, a carboxy derivative or a radical —O—C(O)—(CH 2 ) 2 —X 2 , wherein X 2 is carboxy or an activated carboxylic acid ester as mentioned above.

[0041] Preferably, L 1 is a group of formula 6 embedded image

[0042] g is 0, and L 2 is carboxy, a carboxy derivative, or a radical of formula (1a) above, wherein the above-given meanings and preferences apply.

[0043] According to another preferred embodiment, L 1 is a group —N 3 , g is 1 or preferably 0, R 29 is methyl, methoxy, hydroxy or nitro, and L 2 is amino, carboxy, a carboxy derivative, isocyanato, isothiocyanato or a radical of formula (1a) above, wherein the above-mentioned meanings and preferences apply, in particular amino.

[0044] The compounds of formula (1) may be applied to the material surface according to processes known per se. For example, the bulk material is immersed in a solution of a compound of formula (1), or a layer of a compound of formula (1) is first of all deposited on the bulk material surface to be modified, for example, by dipping, spraying, printing, spreading, pouring, rolling, spin coating or vacuum vapor deposition, with dipping or spraying being preferred. Most preferably, a solution comprising one or more different compounds of the formula (1) is sprayed onto the bulk material surface, which may be dry or preferably wet. The compound of formula (1) may be applied to the material surface in one cycle or in repeated cycles.

[0045] Suitable solvents useful as solvents of the compounds of formula (1) are, for example, water, C 1 -C 4 -alkanols such as methanol, ethanol or iso-propanol, nitrites such as acetonitrile, tetrahydrofuran (THF), aqueous solutions comprising an alkanol, THF or the like, ketones, for example acetone or methylethyl ketone, and also hydrocarbons, for example halogenated hydrocarbons such as methylene chloride or chloroform. The concentration of the compound of formula (1) in the spray solution depends on the specific compound used but is in general in the range of from 0.1 to 100 g/l, preferably 0.5 to 50 g/l, more preferably 0.5 to 25 g/l and in particular 1 to 10 g/l.

[0046] The fixation of the compounds of formula (1) on the bulk material surface then may be initiated, for example, by irradiation, particularly by irradiation with UV or visible light. Suitable light sources for the irradiation are known to the artisan and comprise for example mercury lamps, high pressure mercury lamps, xenon lamps, carbon arc lamps or sunlight. Sensitizers may be used to shift the irradiation wavelength. In addition, a suitable filter may be used to limit the irradiation to a specific wavelength range. Preferably, the bulk material surface to which the compound(s) of formula (1) have been previously applied, is irradiated with light of a wavelength≧250 nm and preferably≧300 nm. The time period of irradiation is not critical but is usually in the range of up to 30 minutes, preferably from 10 seconds to 10 minutes, and more preferably from 15 seconds to 5 minutes, and particularly preferably from 20 seconds to 1 minute. The irradiation may be carried out under ambient conditions or in an atmosphere of inert gas. Masks can be used for the generation of specific surface patterns of functional groups. Following the fixation reaction, any non-covalently bound compounds can be removed, for example by treatment, e.g. extraction, with suitable solvents, for example water, C 1 -C 4 -alkanols, water/C 1 -C 4 -alkanol mixtures or acetonitrile.

[0047] Depending on the desired concentration of functional groups L 2 on the material surface, the above outlined process cycle, (i) contacting, i.e. spraying or dipping, the surface with the compound(s) of formula (1) and (ii) fixing the compound(s) of formula (1) on the surface, i.e. by irradiation, may be carried out once or, preferably, several times. For example, 1 to 100, preferably 1 to 50 and in particular 5 to 25, different layers of one or more compounds of formula (1) are added and fixed on the material surface.

[0048] A polymerization initiator according to step (a) is typically one that is initiating a radical polymerization of ethylenically unsaturated compounds. The radical polymerization may be induced thermally, or preferably by irradiation.

[0049] Initiators for the thermal polymerization are particularly functional initiators having an initiator part such as a peroxide, hydroperoxide, persulfate or azo group and in addition a functional group that is co-reactive with the functional groups L 2 of the modified bulk material surface obtainable, for example, as described above or as disclosed in WO 99/57581. Suitable functional groups that are co-reactive with L 2 are, for example, a carboxy, amino, hydroxy, epoxy or isocyanato group.

[0050] Initiators for the radiation-induced polymerization are particularly functional photoinitiators having a photoinitiator part and in addition a functional group that is co-reactive with the functional groups introduced to the bulk material surface by a plasma treatment according to step (i), or that is co-reactive with the functional groups L 2 of the bulk material surface modified according step (ii). The photoinitiator part may belong to different types, for example to the thioxanthone type and preferably to the benzoin type. Suitable functional groups that are co-reactive with L 2 are, for example, a carboxy, amino, hydroxy, epoxy or isocyanato group.

[0051] Preferred polymerization initiators for use in the present invention are the photoinitiators of formulae (I) and (Ia) as disclosed in U.S. Pat. No. 5,527,925, those of the formula (I) as disclosed in PCT application WO 96/20919, or those of formulae II and III including formulae IIa-IIy and IIIg as disclosed in EP-A-0281941, particularly formulae IIb, IIi, IIm, IIn, IIp, IIr, IIs, IIx and IIIg therein.

[0052] The polymerization initiator moieties are preferably derived from a functional photoinitiator of the formula 7 embedded image

[0053] wherein b1 and b2 are each 0, Z and Z 1 are each bivalent —O—, b3 is 0 or 1; R 4 is methyl or phenyl, or both groups R 4 together are pentamethylene; R 5 is methyl or H; R 3 is hydrogen; a is 1 and R 2 is ethylene, or a is 0 and R 2 is a direct bond; a1 is 0 or 1; and R 1 is branched C 6 -C 10 -alkylene, phenylene or phenylene substituted by from 1 to 3 methyl groups, benzylene or benzylene substituted by from 1 to 3 methyl groups, cyclohexylene or cyclohexylene substituted by from 1 to 3 methyl groups, cyclohexyl-CH 2 — or cyclohexyl-CH 2 — substituted by from 1 to 3 methyl groups,

[0054] T is bivalent —O—; Z 2 is —O—(CH 2 ) y — wherein y is an integer from 1 to 4 and the terminal CH 2 group of which is linked to the adjacent T in formula (3c); R 3 is H; R 8 is methyl, allyl, tolylmethyl or benzyl, R 9 is methyl, ethyl, benzyl or phenyl, or R 8 and R 9 together are pentamethylene, R 10 and R 11 are each independently of the other C 1 -C 4 -alkyl or R 10 and R 11 together are —CH 2 CH 2 OCH 2 CH 2 —, and R 6 is branched C 6 -C 10 -alkylene, phenylene or phenylene substituted by from 1 to 3 methyl groups, benzylene or benzylene substituted by from 1 to 3 methyl groups, cyclohexylene or cyclohexylene substituted by from 1 to 3 methyl groups, cyclohexylene-CH 2 — or cyclohexylene-CH 2 — substituted by from 1 to 3 methyl groups.

[0055] Photoinitiators of formula (3a) and (3b) are particularly preferred.

[0056] Some examples of especially preferred functional photoinitiators are the compounds of formulae 8 embedded image

[0057] or

OCN—CH 2 —C(CH 3 ) 2 —CH 2 —CH(CH 3 )—CH 2 —CH 2 —NH—C(O)—O—R 22 (3d 3 )

[0058] wherein R 22 is a radical 9 embedded image

[0059] The reactions of radicals on the material surface that are derived from a compound of formula (1) having a carboxy, carboxy derivative, isocyanato or isothiocyanato group L 2 with a functional polymerisation initiator having an amino or hydroxy group, or vice versa, are well-known in the art and may be carried out as desribed in textbooks of organic chemistry. For example, the reaction of a radical derived from a compound of formula (1), wherein L 2 is an isocyanato or isothiocyanato group with an amino- or hydroxy-functionalized polymerisation initiator, or vice versa the reaction of an amino- or hydroxy group L 2 with an isocyanato or isothiocyanato functionalized polymerisation initiator, may be carried out in an inert organic solvent such as an optionally halogenated hydrocarbon, for example petroleum ether, methylcyclohexane, toluene, chloroform, methylene chloride and the like, or an ether, for example diethyl ether, tetrahydrofurane, dioxane, or a more polar solvent such as DMSO, DMA, N-methylpyrrolidone or even a lower alcohol, at a temperature of from 0 to 100° C., preferably from 0 to 50° C. and particularly preferably at room temperature, optionally in the presence of a catalyst, for example a tertiary amine such as triethylamine or tri-n-butylamine, 1,4-diazabicyclooctane, or a tin compound such as dibutyltin dilaurate or tin dioctanoate. It is advantageous to carry out the above reactions under an inert atmosphere, for example under a nitrogen or argon atmosphere.

[0060] In case that the radicals on the material surface are derived from a compound of formula (1) having a carboxy group L 2 , the reaction of the carboxy group with an amino or hydroxy group functionalized photoinitiator, or vice versa the reaction of an amino or hydroxy group L 2 with a carboxy functionalized polymerisation initiator, may be carried out under the conditions that are customary for ester or amide formation, for example in an aprotic medium at a temperature from about room temperature to about 100° C. It is further preferred to carry out the esterification or amidation reaction in the presence of an activating agent, for example N-ethyl-N′-(3-dimethylaminopropyl)carbodiimide (EDC), N-hydroxy succinimide (NHS), sulfo-N-hydroxy succinimide or N,N′-dicyclohexyl carbodiimide (DCC) or in the presence of an o-(benztriazole)-uronium salt such as o-(benztriazol-1-y-)-N,N,N,N-tetramethyluronium hexafluorophosphate. Most preferably, the carboxy group L 2 is previously converted to an activated ester using one of the above-mentioned activating agents, and the activated ester is then further reacted with the hydroxy or preferably amino groups of the surface.

[0061] In a preferred embodiment of the invention, L 2 comprises amino, alkylamino or hydroxy, particularly amino, as reactive group and the co-reactive group of the polymerization initiator is an isocyanato group. A preferred polymerization initiator of this embodiment is a photoinitiator of the above formula (3b), (3c), (3d 1 ), (3d 2 ) or (3d 3 ).

[0062] According to another preferred embodiment of the invention, L 2 comprises carboxy, a carboxy derivative, isocyanato or isothiocyanato as reactive group, and the co-reactive group of the polymerization initiator is a hydroxy, amino, alkylamino or thiol group, particularly an amino group. A preferred polymerization initiator of this embodiment is a photoinitiator of the above formula (3a).

[0063] Hydrophilic ethylenically unsaturated macromonomers for graft polymerization from the bulk material surface according to step (b) of the process of the present invention are known, for example, from WO 99/57581. A suitable macromonomer is, for example of formula 10 embedded image

[0064] wherein R 32 is hydrogen, C 1 -C 6 -alkyl or a radical —COOR′;

[0065] R, R′ and R 32 ′ are each independently of the other hydrogen or C 1 -C 6 -alkyl;

[0066] A is a direct bond or is a radical of formula

—C(O)—(A 1 ) n —X— (5a)

[0067] or

—(A 2 ) m —NH—C(O)—X— (5b)

[0068] or

—(A 2 ) m —X—C(O)— (5c)

[0069] or

—C(O)—NH—C(O)—X— (5d)

[0070] or

—C(O)—X 1 —(alk*)—X—C(O)— (5e)

[0071] or

[0072] A and R 32 , together with the adjacent double bond, are a radical of formula 11 embedded image

[0073] A 1 is —O—C 2 -C 12 -alkylene which is unsubstituted or substituted by hydroxy, or is —O—C 2 -C 12 -alkylene-NH—C(O)— or —O—C 2 -C 12 -alkylene-O—C(O)—NH—R 33 —NH—C(O)— or —NH—(Alk*)—C(O)—, wherein (Alk*) is C 1 -C 6 -alkylene and R 33 is linear or branched C 1 -C 18 -alkylene or unsubstituted or C 1 -C 4 -alkyl- or C 1 -C 4 -alkoxy-substituted C 6 -C 10 -arylene, C 7 -C 18 -aralkylene, C 6 -C 10 -arylene-C 1 -C 2 -alkylene-C 6 -C 10 -arylene, C 3 -C 8 -cycloalkylene, C 3 -C 8 -cycloalkylene-C 1 -C 6 -alkylene, C 3 -C 8 -cycloalkylene-C 1 -C 2 -alkylene- C 3 -C 8 -cycloalkylene or C 1 -C 6 -alkylene-C 3 -C 8 -cycloalkylene-C 1 -C 6 -alkylene

[0074] A 2 is C 1 -C 8 -alkylene; phenylene or benzylene;

[0075] m and n are each independently of the other the number 0 or 1;

[0076] X, X 1 and X′ are each independently of the other a bivalent group —O— or —NR″, wherein R″ is hydrogen or C 1 -C 6 -alkyl;

[0077] (alk*) is C 2 -C 12 -alkylene;

[0078] and (oligomer) denotes

[0079] (i) the radical of a telomer of formula 12 embedded image

[0080] wherein (alk) is C 2 -C 12 -alkylene,

[0081] Q is a monovalent group that is suitable to act as a polymerization chain-reaction terminator,

[0082] p and q are each independently of another an integer from 0 to 350, wherein the total of (p+q) is an integer from 2 to 350,

[0083] and B and B′ are each independently of the other a 1,2-ethylene radical derivable from a copolymerizable vinyl monomer by replacing the vinylic double bond by a single bond, at least one of the radicals B and B′ being substituted by a hydrophilic substituent; or

[0084] (ii) the radical of an oligomer of the formula 13 embedded image

[0085] wherein R 19 is hydrogen or unsubstituted or hydroxy-substituted C 1 -C 12 -alkyl, u is an integer from 2 to 250 and Q′ is a radical of a polymerization initiator; or

[0086] (iii) the radical of formula 14 embedded image

[0087] wherein R 19 , X and u are as defined above, or

[0088] (iv) the radical of an oligomer of formula 15 embedded image

[0089] wherein R 20 and R 20 ′ are each independently C 1 -C 4 -alkyl, An − is an anion, v is an integer from 2 to 250, and Q″ is a monovalent group that is suitable to act as a polymerization chain-reaction terminator; or

[0090] (v) the radical of an oligopeptide of formula

—(CHR 21 —C(O)—NH) t —CHR 21 —COOH (6d)

[0091] or

—CHR 21 —(NH—C(O)—CHR 21 ) t —NH 2 (6d′)

[0092] wherein R 21 is hydrogen or C 1 -C 4 -alkyl which is unsubstituted or substituted by hydroxy, carboxy, carbamoyl, amino, phenyl, o- , m- or p-hydroxyphenyl, imidazolyl, indolyl or a radical —NH—C(═NH)—NH 2 and t is an integer from 2 to 250, or the radical of an oligopeptide based on proline or hydroxyproline; or

[0093] (vi) the radical of a polyalkylene oxide of formula

—(alk ** —O) z —[CH 2 —CH 2 —O] r —[CH 2 —CH(CH 3 )—O] s —R 34 (6e)

[0094] wherein R 34 is hydrogen or C 1 -C 24 -alkyl, (alk ** ) is C 2 -C 4 -alkylene, z is 0 or 1, r and s are each independently an integer from 0 to 250 and the total of (r+s) is from 2 to 250; or

[0095] (vii) the radical of an oligosaccharide;

[0096] subject to the provisos that

[0097] A is not a direct bond if (oligomer) is a radical of formula (6a);

[0098] A is a radical of formula (5a), (5b) or (5d) or A and R 32 , together with the adjacent double bond, are a radical of formula (5f) if (oligomer) is a radical of formula (6b), (6c), (6d) or (6e) or is the radical of an oligosaccharide;

[0099] A is a direct bond if (oligomer) is a radical of formula (6b′); and

[0100] A is a radical of formula (5c) or (5e) if (oligomer) is a radical of formula (6d′).

[0101] The following preferences apply to the variables contained in the definition of the macromonomer of formula (4):

[0102] R′ is preferably hydrogen or C 1 -C 4 -alkyl, more preferably hydrogen or C 1 -C 2 -alkyl and particularly preferably hydrogen.

[0103] R 32 is preferably hydrogen, methyl or carboxyl, and particularly preferably hydrogen.

[0104] R is preferably hydrogen or methyl.

[0105] X is preferably a bivalent group —O— or —NH—. X is particularly preferably the group —NH— if (oligomer) is a radical of formula (6a); (6c) or (6d), and is particularly preferably the group —O— if (oligomer) is a radical of formula (6b) or (6e) or is the radical of an oligosaccharide. X′ is preferably —O— or —NH— and more preferably —NH—. X 1 is preferably —O— or —NH—.

[0106] The radical R 33 has a symmetrical or, preferably, an asymmetrical structure. R 33 is preferably linear or branched C 6 -C 10 alkylene; cyclohexylene-methylene or cyclohexylene-methylene cyclohexylene each unsubstituted or substituted in the cyclohexyl moiety by from 1 to 3 methyl groups; or phenylene or phenylene-methylene-phenylene each unsubstituted or substituted in the phenyl moiety by methyl. The bivalent radical R 33 is derived preferably from a diisocyanate and most preferably from a diisocyanate selected from the group isophorone diisocyanate (IPDI), toluylene-2,4-diisocyanate (TDI), 4,4′-methylenebis(cyclohexyl iso-cyanate), 1,6-diisocyanato-2,2,4-trimethyl-n-hexane (TMDI), methylenebis(phenyl isocyanate), methylenebis(cyclohexyl-4-isocyanate) and hexamethylene diisocyanate (HMDI).

[0107] Preferred meanings of A 1 are unsubstituted or hydroxy-substituted —O—C 2 -C 8 -alkylene or a radical —O—C 2 -C 6 -alkylene—NH—C(O)— and particularly —O—(CH 2 ) 2-4 —, —O—CH 2 —CH(OH)—CH 2 — or a radical —O—(CH 2 ) 2-4 —NH—C(O)—. A particularly preferred meaning of A 1 is the radical —O—(CH 2 ) 2 —NH—C(O)—.

[0108] A 2 is preferably C 1 -C 6 -alkylene, phenylene or benzylene, more preferably C 1 -C 4 -alkylene and even more preferably C 1 -C 2 -alkylene.

[0109] n is an integer of 0 or preferably 1. m is preferably an integer of 1.

[0110] R 32 ′ is preferably hydrogen or methyl and particularly preferably hydrogen.

[0111] In case that (oligomer) is a radical of formula (6a), (6b), (6c), (6d) or (6e) or is the radical of an oligosaccharide, is A preferably a radical of formula (5a) or (5b) and particularly preferably a radical of formula (5a), wherein the above given meanings and preferences apply for the variables contained therein.

[0112] A preferred group of hydrophilic macromonomers according to the invention comprises compounds of the above formula (4), wherein R is hydrogen or methyl, R 32 is hydrogen, methyl or carboxyl, R 32 ′ is hydrogen, A is a radical of the formula (5a) or (5b) and (oligomer) is a radical of formula (6a), (6b), (6c), (6d) or (6e) or is the radical of an oligosaccharide. An even more preferred group of hydrophilic macromonomers comprises compounds of the above formula (4), wherein R is hydrogen or methyl, R 32 and R 32 ′ are each hydrogen, A is a radical of the formula (5a) and (oligomer) is a radical of formula (6a). A further group of preferred macromonomers comprises compounds of formula (4), wherein A is a radical of formula (5e) above and (oligomer) is a radical of formula (6a).

[0113] (Alk*) is preferably methylene, ethylene or 1,1-dimethyl-methylene, in particular a radical —CH 2 — or —C(CH 3 ) 2 —. (alk) and (alk*) are each independently preferably C 2 -C 8 -alkylene, more preferably C 2 -C 6 -alkylene, even more preferably C 2 -C 4 -alkylene and particularly preferably 1,2-ethylene. The alkylene radicals (alk) and (alk*) may be branched or preferably linear alkylene radicals.

[0114] Q is for example hydrogen.

[0115] The total of (p+q) is preferably an integer from 2 to 150, more preferably from 5 to 100, even more preferably from 5 to 75 and particularly preferably from 10 to 50. In a preferred embodiment of the invention q is 0 and p is an integer from 2 to 250, preferably from 2 to 150, more preferably from 5 to 100, even more preferably from 5 to 75 and particularly preferably from 10 to 50.

[0116] Suitable hydrophilic substituents of the radicals B or B′ are those described in WO 99/57581 on pages 16 to 24.

[0117] A group of preferred non-ionic substituents of B or B′ comprises C 1 -C 2 -alkyl, which is unsubstituted or substituted by —OH or —NR 23 R 23 ′, wherein R 23 and R 23 ′ are each independently of the other hydrogen or C 1 -C 2 -alkyl; a radical —COOY wherein Y is C 1 -C 4 -alkyl; C 2 -C 4 -alkyl which is substituted by —OH, —NR 23 R 23 ′ wherein R 23 and R 23 ′ are each independently of another hydrogen or C 1 -C 2 -alkyl, or Y is a radical —C 2 -C 4 -alkylene—NH—C(O)—O—G wherein —O—G is the radical of a saccharide; a radical —C(O)—NY 1 Y 2 , wherein Y 1 and Y 2 are each independently of the other hydrogen or C 1 -C 6 -alkyl which is unsubstituted or substituted by hydroxy, or Y 1 and Y 2 together with the adjacent N-atom form a heterocyclic 6-membered ring having no further heteroatom or having one further N- or O-atom; a radical —OY 3 , wherein Y 3 is hydrogen, C 1 -C 4 -alkyl which is unsubstituted or substituted by —NH 2 or —N(C 1 -C 2 -alkyl) 2 , or is a group —C(O)C 1 -C 2 -alkyl; or a 5- or 6-membered heteroaromatic or heteroaliphatic radical having one N-atom and in addition no further heteroatom or an additional N- , O- or S-heteroatom, or a 5 to 7-membered lactame.

[0118] A group of more preferred non-ionic substituents of B or B′ comprises a radical —COOY, wherein Y is C 1 -C 2 -alkyl, C 2 -C 3 -alkyl, which is substituted by hydroxy, amino or N,N-di-C 1 -C 2 -alkylamino, or is a radical -C 2 -C 4 -alkylene—NH—C(O)—O—G wherein —O—G is the radical of trehalose; a radical —CO—NY 1 Y 2 , wherein Y 1 and Y 2 are each independently of the other hydrogen or C 1 -C 4 -alkyl which is unsubstituted or substituted by hydroxy, or Y 1 and Y 2 together with the adjacent N-atom form a N—C 1 -C 2 -alkylpiperazino or morpholino ring; or a heterocyclic radical selected from the group consisting of N-pyrrolidonyl, 2- or 4-pyridinyl, 2-methylpyridin-5-yl, 2-, 3- oder 4-hydroxypyridinyl, N-ε-caprolactamyl, N-imidazolyl, 2-methylimidazol-1-yl, N-morpholinyl and 4-N-methylpiperazin-1-yl.

[0119] A particularly preferred group of non-ionic substituents of B or B′ comprises the radicals —CONH 2 , —CON(CH 3 ) 2 , 16 embedded image

[0120] —CONH—(CH 2 ) 2 —OH, —COO—(CH 2 ) 2 —N(CH 3 ) 2 , and —COO(CH 2 ) 2-4 —NHC(O)—O—G wherein —O—G is the radical of trehalose.

[0121] Particularly preferred anionic substituents of B or B′ are —COOH, —SO 3 H, o-, m- or p-sulfophenyl, o-, m- or p-sulfomethylphenyl or a radical —CONY 5 Y 6 wherein Y 5 is C 2 -C 4 -alkyl substituted by sulfo, and Y 6 is hydrogen.

[0122] A preferred cationic substituent of B or B′ is a radical —C(O)OY 7 wherein Y 7 is C 2 -C 4 -alkyl, which is substituted by —N(C 1 -C 2 -alkyl) 3 + An − and is further substituted by hydroxy, and An − is an anion, for example the radical —C(O)O—CH 2 —CH(OH)—CH 2 —N(CH 3 ) 3 + An − .

[0123] A preferred group of zwitter-ionic substituents —R 24 —Zw corresponds to the formula

—C(O)O—(alk′″)—N(R 23 ) 2 + —(alk′)—An −

[0124] or

—C(O)O—(alk″)—O—PO 2 —(O) 0-1 —(alk′″)—N(R 23 ) 3 +

[0125] wherein R 23 is hydrogen or C 1 -C 6 -alkyl; An + is an anionic group —COO − , —SO 3 − , —OSO 3 − or —OPO 3 H − , preferably —COO − or —SO 3 − and most preferably —SO 3 − , alk′ is C 1 -C 12 -alkylene, (alk″) is C 2 -C 24 -alkylene which is unsubstituted or substituted by a radical —OY 8 , Y 8 is hydrogen or the acyl radical of a carboxylic acid, and (alk′″) is C 2 -C 8 -alkylene.

[0126] (alk′) is preferably C 2 -C 8 -alkylene, more preferably C 2 -C 6 -alkylene and most preferably C 2 -C 4 -alkylene. (alk″) is preferably C 2 -C 12 -alkylene, more preferably C 2 -C 6 -alkylene and particularly preferably C 2 -C 3 -alkylene which is in each case unsubstituted or substituted by hydroxy or by a radical —OY 8 . (alk′″) is preferably C 2 -C 4 -alkylene and more preferably C 2 -C 3 -alkylene. R 23 is hydrogen or C 1 -C 4 -alkyl, more preferably methyl or ethyl and particularly preferably methyl. A preferred zwitterionic substituent of B or B′ is of formula

—C(O)O—CH 2 —CH(OY 8 )—CH 2 —O—PO 2 − —(CH 2 ) 2 —N(CH 3 ) 3 +

[0127] wherein Y 8 is hydrogen or the acyl radical of a higher fatty acid.

[0128] B denotes for example a radical of formula 17 embedded image

[0129] wherein R 25 is hydrogen or C 1 -C 4 -alkyl, preferably hydrogen or methyl; R 26 is a hydrophilic substituent, wherein the above given meanings and preferences apply; R 27 is C 1 -C 4 -alkyl, phenyl or a radical —C(O)OY 9 , wherein Y 9 is hydrogen or unsubstituted or hydroxy-substituted C 1 -C 4 -alkyl; and R 28 is a radical —C(O)Y 9 ′ or —CH 2 —C(O)OY 9 ′ wherein Y 9 ′ independently has the meaning of Y 9 .

[0130] R 27 is preferably C 1 -C 2 -alkyl, phenyl or a group —C(O)OY 9 . R 28 is preferably a group —C(O)OY 9 ′ or —CH 2 —C(O)OY 9 ′ wherein Y 9 and Y 9 ′ are each independently of the other hydrogen, C 1 -C 2 -alkyl or hydroxy-C 1 -C 2 -alkyl. Particularly preferred —CHR 27 —CHR 28 — units according to the invention are those wherein R 27 is methyl or a group —C(O)OY 9 and R 28 is a group —C(O)OY 9 ′ or —CH 2 —C(O)OY 9 ′ wherein Y 9 and Y 9 ′ are each hydrogen, C 1 -C 2 -alkyl or hydroxy-C 1 -C 2 -alkyl.

[0131] B′ independently may have one of the meanings given above for B.

[0132] If (oligomer) is a radical of formula (6a), the radical —(alk)—S—[B] p —[B′] q —Q preferably denotes a radical of formula 18 embedded image

[0133] even more preferably of the formula

[0134] wherein for R 25 , R 26 , Q, p and q the above-given meanings and preferences apply, for R 25 ′ independently the meanings and preferences given before for R 25 apply, and for R 26 ′ independently the meanings and preferences given before for R 26 apply.

[0135] A preferred group of suitable hydrophilic macromonomers according to step (b) of the invention comprises compounds of formula 19 embedded image

[0136] wherein R is hydrogen or methyl, A 1 is —O—(CH 2 ) 24 —, —O—CH 2 —CH(OH)—CH 2 — or a radical —O—(CH 2 ) 2-4 —NH—C(O)—, X is —O— or —NH—, (alk) is C 2 -C 4 -alkylene, Q is a monovalent group that is suitable to act as a polymerization chain-reaction terminator, p is an integer from 5 to 50, R 25 and R 25 ′ are each independently of the other hydrogen or methyl, and for R 26 and R 26 ′ each independently the above given meanings and preferences apply.

[0137] A particularly preferred embodiment of the invention relates to hydrophilic macromonomers of the formula 20 embedded image

[0138] wherein for R, R 25 , R 26 , Q, (alk) and p the above-given meanings and preferences apply. A particularly preferred group of hydrophilic macromonomers are compounds of the above formula (4b) wherein R is hydrogen or methyl, (alk) is C 2 -C 4 -alkylene, R 25 is hydrogen or methyl, p is an integer of 5 to 50, Q is as defined before, and for R 26 the above given meanings and preferences apply; in particular R 26 of this embodiment is a radical —CONH 2 , —CON(CH 3 ) 2 or 21 embedded image

[0139] If (oligomer) is a radical (ii) of formula (6b), Q′ in formula (6b) is for example C 1 -C 12 -alkyl, phenyl or benzyl, preferably C 1 -C 2 -alkyl or benzyl and in particular methyl. R 19 is preferably unsubstituted or hydroxy-substituted C 1 -C 4 -alkyl and in particular methyl. u is preferably an integer from 2 to 150, more preferably from 5 to 100, even more preferably from 5 to 75 and particularly preferably from 10 to 50.

[0140] If (oligomer) is a radical of formula (6b′), the above given meanings and preferences apply for the variables R 19 and u contained therein. X in formula (6b′) is preferably hydroxy or amino.

[0141] If (oligomer) denotes a radical (iv) of formula (6c), R 20 and R 20 ′ are each preferably ethyl or in particular methyl; v is preferably an integer from 2 to 150, more preferably from 5 to 100, even more preferably from 5 to 75 and particularly preferably from 10 to 50; Q″ is for example hydrogen; and An − is as defined before.

[0142] If (oligomer) denotes an oligopeptide radical (v) of formula (6d) or 6d′), R 21 is for example hydrogen, methyl, hydroxymethyl, carboxymethyl, 1-hydroxyethyl, 2-carboxyethyl, isopropyl, n-, sec. or iso-butyl, 4-amino-n-butyl, benzyl, p-hydroxybenzyl, imidazolylmethyl, indolylmethyl or a radical —(CH 2 ) 3 —NH—C(═NH)—NH 2 . t is preferably an integer from 2 to 150, more preferably from 5 to 100, even more preferably from 5 to 75 and particularly preferably from 10 to 50.

[0143] If (oligomer) denotes a polyoxyalkylene radical (vi) of formula (6e), R 34 is preferably hydrogen or C 1 -C 18 -alkyl, more preferably hydrogen or C 1 -C 12 -alkyl, even more preferably hydrogen, methyl or ethyl, and particularly preferably hydrogen or methyl. (alk **) is preferably a C 2 -C 3 -alkylene radical. z is preferably 0. r and s are each independently preferably an integer from 0 to 100 wherein the total of (r+s) is 5 to 100. r and s are each independently more preferably an integer from 0 to 50 wherein the total of (r+s) is 8 to 50. In a particularly preferred embodiment of the polyoxyalkylene radicals (oligomer), r is an integer from 8 to 50 and particularly 9 to 25, and s is 0. (oligomer) as the radical of an oligosaccharide (vii) may be, for example, a di- or polysaccharide including carbohydrate containing fragments from a biopolymer. Examples are the radical of a cyclodextrin, trehalose, cellobiose, maltotriose, maltohexaose, chitohexaose or a starch, hyaluronic acid, deacetylated hyaluronic acid, chitosan, agarose, chitin 50, amylose, glucan, heparin, xylan, pectin, galactan, glycosaminoglycan, mucin, dextran, aminated dextran, cellulose, hydroxyalkylcellulose or carboxyalkylcellulose oligomer, each of which with a molecular weight average weight of, for example, up to 25,000 Da, preferably up to 10,000 Da. Preferably the oligosaccharide according to (vii) is the radical of a cyclodextrin with a maximum of 8 sugar units.

[0144] Formulae (6a), (6a′) or (6e) are to be understood as a statistic description of the respective oligomeric radicals, that is to say, the orientation of the monomers and the sequence of the monomers (in case of copolymers) are not fixed in any way by said formulae. The arrangement of B and B′ in formula (6a) or of the ethyleneoxide and propyleneoxide units in formula (6e) thus in each case may be random or blockwise.

[0145] The weight average molecular weight of the hydrophilic macromonomer according to step (b) depends principally on the desired properties and is for example from 300 to 25000 Da, preferably from 300 to 12,000 Da, more preferably from 300 to 8000 Da, even more preferably from 300 to 5000 Da, and particularly preferably from 500 to 4000 Da.

[0146] The macromonomers of formula (4) may be prepared by methods known per se, as described in, for example, WO 99/57581.

[0147] A wide variety of structurally different polymers are suitable for use in step (b) of the present invention subject to the condition that said polymers lack polymerizable ethylenically unsaturated groups and are hydrophilic and biocompatible. Suitable biocompatible hydrophilic polymers comprise, for example, biopolymers, modified biopolymers and synthetic polymers.

[0148] The weight average molecular weight M w of biocompatible hydrophilic polymers according to step (b) depends principally on the desired properties and is from 1000 to 5,000,000 Da, preferably from 10,000 to 1,000,000 Da, and particularly preferably from 100,000 to 500,000 Da.

[0149] Examples of suitable biopolymers are polysaccharides, for example, hyaluronic acid, chondriotin sulfate, dextran, 1,3-glucan, fucoidan; glycoproteins, for example, mucin, fibronectin; glucosamines, for example chitin, chitosan, heparin; polypeptides, for example, lysozyme, collagen; proteins, for example albumen, immunoglobulines.

[0150] Examples of suitable modified biopolymers are, for example, carboxyalkylcellulose, for example carboxymethylcellulose, carboxyalkylchitin, carboxyalkylchitosan.

[0151] Examples of suitable synthetic polymers are bis-aminoalkylene-polyalkylene glycols of various average molecular weights, for example a Jeffamine® polyoxyalkylene amines; polyethyleneglycols, poly(hydroxyethyl methacrylate (poly-HEMA), high molecular weight, crosslinked, acrylic acid based polymers, for example, Carbopol® polymers and Noveon® Polycarbophils; polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol.

[0152] Preferred biocompatible hydrophilic polymers are highly branched and/or possess molecular weights>40,000 Da. Especially preferred are hyarulonic acid, dextran, heparin, chondriotin sulfate, mucin, polyvinylpyrrolidone or a Polycarbophil or Carbopol® polymer.

[0153] The biocompatible hydrophilic polymer is not covalently bonded to the polymer chains of the macromonomer. Chain entanglement, hydrogen bonds, Van der Waals forces and charge interactions are among the most important interactions between the hydrophilic macromonomers grafted from the bulk material and the biocompatible hydrophilic polymer. These forces stabilize the entangled biocompatible hydrophilic polymer and prevent it's rapid leaching from the interpenetration mixture under physiological conditions. Preferably, the biocompatible hydrophilic polymers contribute significantly to specific advantageous features of the s-IPN-structured coating. Among those are for example: lubrication, water retention and stabilization of aqueous surface layers, biocompatibility, reversible attraction of biomolecules (e.g. mucins) from biological fluids, prevention of irreversible deposition of proteins, lipids and salts and inhibition of microbial adhesion. Controlled low rate leaching of entangled biocompatible hydrophilic polymers out of the contact lens coatings can enhance lubricity and comfort, and in addition can favour a continuous renewal of the lens surface.

[0154] Additional components can be included within the s-IPN. They can either be uncrosslinked polymers, oligomers or low molecular weight components with their leaching rates from the s-IPN naturally increasing with descreasing molecular masses. An additional component is preferably a bioactive material or a bioactive polymer. In a particular embodiment of the invention an additional component can be an enzyme, an antibody, an antimicrobial peptide, a polyquat or a growth factor. It is characteristic for additional components that they slowly release from the coating under physiological conditions.

[0155] The practical use of devices and articles carrying coatings according to the disclosed technology can be seen in technical, in biological and in environmental systems. Applications in the biomedical field are preferred: in particular, coatings for ophthalmic devices and implants, such as contact lenses, ocular drug delivery systems, intraocular lenses and artificial corneas.

[0156] In addition, s-IPN coatings of the present invention are outstanding with regard to their capability of lubricating contact lens surfaces and thus reducing the blinking frequency and the overall wearing comfort of contact lens users. By lubricating the cornea surface (via leachables) contact lens coatings of the present invention can improve the on-eye mobility of contact lens. All this is of particular importance with regard to extended wear contact lenses. These advantageous effects can be caused or be enhanced by leaching of B and/or C. The surface coatings of the invention can also be applied to ophthalmic implants. In technical applications coatings of the present invention can prevent befouling of separation membranes and can reduce friction, calcification, scale and drag phenomena in hydrodynamic systems.

[0157] The mixture of hydrophilic macromonomers and biocompatible hydrophilic polymer may be applied to the initiator-modifi