Photo-curing of thermoplastic coatings

Abstract

The present invention relates to a method for the preparation of a medical device element by means of extrusion or injection moulding and to medical devices comprising such extruded or injection moulded medical device elements. The medical device elements (e.g. tubes, wires, lines, stents, catheters, guides, endodontic instruments, needles, trocars for e.g. laparoscopic surgery, laparoscopic accessories, surgical instruments, guide wires) are characterized by a prefabricated shaped article or a thermoplastic substrate polymer having thereon a layer of a covalently cross-linked coating composition of a thermoplastic matrix polymer and a hydrophilic polymer. The method involves a coating composition comprising a thermoplastic matrix polymer, a hydrophilic polymer, and one or more photo-initiator(s), e.g. covalently linked to molecules of the thermoplastic matrix polymer and/or to molecules of the hydrophilic polymer. The coating composition is irradiated with UV or visible light so as to covalently cross-link said coating composition.

1 - 23 . (canceled) 
   
   
       24 . A method for the preparation of a medical device element, said method comprising the steps of:
 (i) providing a prefabricated shaped article and/or a thermoplastic substrate polymer;   (ii) providing a coating composition comprising a thermoplastic matrix polymer, a hydrophilic polymer, and one or more photo-initiator(s);   (iii) extruding, injection moulding or powder coating the coating composition of step (ii) on the prefabricated shaped article and/or the thermoplastic substrate polymer of step (i) so as to provide the medical device element of said prefabricated shaped article and/or said substrate polymer having thereon a layer of said coating composition, wherein, when both of said prefabricated shaped article and said substrate polymer are present, said prefabricated shaped article has thereon a layer of said substrate polymer;   (iv) irradiating the coating composition with UV or visible light so as to covalently cross-link said coating composition.   
   
   
       25 . The method according to  claim 24 , wherein the one or more photo-initiator(s) is at least two different photo-initiators. 
   
   
       26 . The method according to  claim 24 , wherein one or more photo-initiator moieties are covalently linked to a polymer. 
   
   
       27 . The method according to  claim 24 , wherein said one or more photo-initiators are covalently linked to molecules of the thermoplastic matrix polymer and/or to molecules of the hydrophilic polymer. 
   
   
       28 . The method according to  claim 26 , wherein the one or more photo-initiator moieties are covalently linked to a polymer selected from the group consisting of polyurethanes, polyethylene glycols, poly(lactic acid)s, collagen, nylons, vinyl polymers, and polysaccharides. 
   
   
       29 . The method according to  claim 24 , wherein a plurality of photo-initiator moieties are covalently linked to a scaffold. 
   
   
       30 . The method according to  claim 24 , wherein the coating composition does not comprise (meth)acrylic monomers. 
   
   
       31 . The method according to  claim 24 , wherein the thermoplastic matrix polymer is selected from the group consisting of hydrophilic polyurethane polymers and amphiphilic block-copolymers. 
   
   
       32 . The method according to  claim 24 , wherein the hydrophilic polymer is a poly(ethylene oxide). 
   
   
       33 . The method according to  claim 24 , wherein a prefabricated shaped article is provided in step (i), and wherein step (iii) involves extruding, injection moulding or powder coating the coating composition of step (ii) on the prefabricated shaped article of step (i) so as to provide the medical device element of said prefabricated shaped article having thereon a layer of said coating composition. 
   
   
       34 . The method according to  claim 24 , wherein a thermoplastic substrate polymer is provided in step (i), and wherein step (iii) involves extruding or injection moulding the coating composition of step (ii) together with the thermoplastic substrate polymer of step (i) so as to provide the medical device element of said thermoplastic substrate polymer having thereon a layer of said coating composition. 
   
   
       35 . The method according to  claim 24 , wherein a prefabricated shaped article and a thermoplastic substrate polymer are provided in step (i), and wherein step (iii) involves extruding, injection moulding or powder coating the coating composition of step (ii) on the prefabricated shaped article together with the thermoplastic substrate polymer of step (i) so as to provide the medical device element of said prefabricated shaped article and said thermoplastic substrate polymer, said prefabricated shaped article having thereon a layer of said thermoplastic substrate polymer and said thermoplastic substrate polymer having thereon a layer of said coating composition. 
   
   
       36 . A medical device comprising a medical device element of a thermoplastic substrate polymer having thereon a layer of a covalently cross-linked coating composition of (a) a thermoplastic matrix polymer and (b) a hydrophilic polymer; wherein said coating composition is (co)extruded or injection moulded with said thermoplastic substrate polymer; and wherein the covalent cross-linking of the coating composition is the result of the presence of one or more photo-initiators in the coating composition and the exposure of the coating composition to UV or visible light. 
   
   
       37 . A medical device comprising a medical device element of a prefabricated shaped article having thereon a layer of a covalently cross-linked coating composition of (a) a thermoplastic matrix polymer and (b) a hydrophilic polymer; wherein said coating composition is extruded or injection moulded with said prefabricated shaped article; and wherein the covalent cross-linking of the coating composition is the result of the presence of one or more photo-initiators in the coating composition and the exposure of the coating composition to UV or visible light. 
   
   
       38 . A medical device comprising a medical device element of a prefabricated shaped article having thereon a layer of a thermoplastic substrate polymer, where said thermoplastic substrate polymer has thereon a layer of a covalently cross-linked coating composition of (a) a thermoplastic matrix polymer and (b) a hydrophilic polymer; wherein said coating composition is (co)extruded or injection moulded with said prefabricated shaped article and said thermoplastic substrate polymer; and wherein the covalent cross-linking of the coating composition is the result of the presence of one or more photo-initiators in the coating composition and the exposure of the coating composition to UV or visible light. 
   
   
       39 . The medical device according to  claim 36 , wherein one or more photo-initiator moieties are covalently linked to a polymer. 
   
   
       40 . The medical device according to  claim 37 , wherein one or more photo-initiator moieties are covalently linked to a polymer. 
   
   
       41 . The medical device according to  claim 38 , wherein one or more photo-initiator moieties are covalently linked to a polymer.