Uv-curable coating for medical device

Abstract

To provide a coating composition having hydrophobic polymers to be used as photoreactive basecoat for a medical device or implant.SOLUTION: A coating composition for a medical device or medical implant has polymers soluble in water or water-alcohol solution, where the polymer is made of (a) at least one monomer being photoradical generator having one or more of 4-methacryloxy-2-hydroxybenzophenone, 4-acryloxy benzophenone, 4-methacryloxy benzophenone and the like, and (b) one or more monomers having (i) an ethylenic monomer having at least one acidic group and (ii) at least one monomer having one or more or both of acrylate and acrylamide.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to ultraviolet curable coatings for medical devices and implants.

Background Art

[0002] The present invention relates to the field of non-thrombogenic and lubricious coatings applied to medical devices, particularly devices intended to be implanted temporarily or permanently for in-vivo and blood contact applications and for blood contact applications.

[0003] Among the many advances in recent medical practice are medical devices that supplement the skills of surgeons. Examples of these include vascular catheters and guidewires, which are used to treat remote areas of the circulatory system that were previously treatable only by surgery. Others include stents, which are devices that reinforce arterial walls and prevent occlusion after angioplasty. Others include intraocular lenses that restore the vision of the elderly suffering from cataracts. Furthermore, there are countless others such as heart valves, artificial pacemakers, orthopedic implants, and so on.

[0004] Nearly all of the above devices are composed of plastics and metals that are not intended to penetrate the human body and, in some cases, are not intended to be present in the human body for long periods of time. These generally have a hydrophilic, slippery, and non-biological surface that is not similar to the surface of human organs with excellent biocompatibility.

[0005] Equally important for devices that need to be inserted through body tissue and moved within the body is their lubricity. Many metals and plastics have low lubricity against body tissue, causing mechanical wear and discomfort when the device passes over body tissue.

[0006] The surfaces of devices designed and manufactured from such materials can have their biocompatibility, hydrophilicity, and slipperiness improved by a properly designed coating. Thus, a path has been opened for constructing medical devices from conventional plastics and metals having the specific physical properties required, and then applying a suitable coating to their surfaces to impart the desired properties.

[0007] Polymers with a low coefficient of friction when wet have been shown to be water-soluble polymers that are crosslinked or immobilized by other means and swell when contacted with water but do not dissolve. Polysaccharides have been shown to be useful for creating hydrophilic and lubricious coatings on substrates. Such coatings are described in U.S. Patent Nos. 4,801,000, 4,801,475, 5,023,114, 5,037,677, and 6,673,453 (the disclosures of which are incorporated herein by reference). Polysaccharide-based lubricious coatings exhibit excellent biocompatibility and lubricity, but have relatively low resistance to ionizing radiation.

[0008] For some applications, it is desirable to have a lubricious coating made of a synthetic polymer for the advantages of longer shelf life and stability to radiation sterilization. Hydrophilic synthetic polymers such as poly(acrylic acid) and its copolymers have often been proposed for creating lubricious hydrophilic coatings because of their ability to form a hydrated layer on the surface.

[0009] Attempts have been made to immobilize poly(acrylic acid) on surfaces for use as coatings for medical devices. The methods in U.S. Patent Nos. 4,642,267 and 4,990,357 involve physical mixing of a poly(acrylic acid) copolymer and a polyurethane dispersion. This method has the disadvantage that the polymer network that physically adheres the hydrophilic polymer to the substrate surface is often disrupted by prolonged turbulent flow or immersion, washing away the hydrophilic species, thereby rendering the lubricity of the article insufficient.

[0010] As other methods invented for utilizing poly(acrylic acid) as a hydrophilic coating on the surface, there are, for example, the radiation grafting of carboxylic acid monomers and their polymers described in U.S. Patent Nos. 2,999,056, 5,531,715, 5,789,018, and 6,221,061, and EP0669837, and also methods for fixing polyacrylic acid using primer layers containing isocyanate, aziridine, amine, and hydroxyl functional groups described in U.S. Patent Nos. 5,091,205, 5,509,899, 5,702,754, 6,048,620, 6,558,798, 6,709,706, 6,087,416, 6,534,559, and EP0379156, EP0480809, EP0728487, and EP0963761. The disclosure contents of all the above patents are incorporated herein by reference.

[0011] The above poly(acrylic acid) coating exhibits relatively insufficient lubricity and / or durability because the coating thickness of the hydrophilic polymer is insufficient and / or the binding force to the surface is insufficient. It is difficult to achieve a high-density surface coating by either grafting through photoinitiated polymerization or surface chemical attachment of the polymer. Although a coating process repeated multiple times may increase the thickness of the photoinitiated polymerization coating, it leads to a significant decrease in productivity and an increase in manufacturing costs.

[0012] The use of a crosslinking agent can significantly increase the thickness of the hydrophilic coating. The prior art includes methods of crosslinking polyacrylic acid coatings by light irradiation and by reaction of polyfunctional reactive compounds such as melamine and aziridine, as described in U.S. Pat. Nos. 5,531,715, 6,558,798, and EP533821. However, crosslinked hydrophilic coatings in the art often face a trade-off between lubricity and wear resistance, both of which are essential properties for hydrophilic coatings. Highly crosslinked coatings have poor lubricity due to low hydration ability and low mobility of polymer segments in the aqueous medium. Also, coatings with low crosslink density have a high swelling ratio and generally low wear resistance and weak mechanical strength.

[0013] U.S. Patent Application Publication No. 2011 / 0200828 teaches a two-layer coating comprising a base coat firmly adhering to a substrate and a top coat chemically grafted to the base coat. The top coat has a mixture of a water-soluble polymer containing carboxylic acid groups and a water-soluble chromium(III) compound. This coating is highly durable when wet and forms a lubricious layer. However, the carboxylate anions constituting this coating exhibit poor performance in thrombogenicity tests such as the partial thromboplastin time (PTT) test. The disclosure of the above-cited reference is incorporated herein by reference.

[0014] When blood contacts a foreign object having a plastic or metal surface, a complex series of thrombogenic reactions occur at the interface of the blood surface. Thromboembolism is a major complication associated with the clinical use of artificial devices such as catheters, guidewires, mechanical heart valves, ventricular assist devices, implantable artificial hearts, and artificial blood vessels. In particular, thromboembolism is an important complication associated with angiographic procedures, especially catheter and guidewire manipulations in proximity to the brachiocephalic artery.

[0015] Surface modification is commonly performed to make materials more blood-compatible while minimizing loss of mechanical properties. Two approaches are commonly used for surface modification. Suppression of non-specific protein adsorption using coatings of polyethylene oxide (PEO), a polymer that is neutral, hydrophilic, and highly flexible, and other hydrophilic polymers has been investigated for surface passivation. Non-specific protein adsorption occurs typically within seconds after a foreign object contacts blood and can initiate blood coagulation and the complement pathway.

[0016] The second approach was to use coatings that actively assist the anticoagulant activity of the surface. Specific plasma proteins, such as antithrombin (AT), which can inhibit thrombin and factor Xa (FXa), or heparin, a glycosaminoglycan that catalyzes the reaction of plasma AT, have been used for this purpose. Frech et al., in "A Simple Noninvasive Technique to Test Nonthrombogenic Surfaces," The American Journal of Roentgenology, vol. 113 (1971), p. 765-768, disclose coating guidewires with a benzalkonium-heparin complex. Ovitt et al., in "Guidewire Thrombogenicity and Its Reduction", Radiology, vol. 111 (1974), p. 43-46, report on Teflon-coated guidewires treated with benzalkonium heparin. U.S. Patent No. 4,349,467 (William) shows that heparin can be applied to a solid polymer resin substrate by immersing the substrate in a solution of an ammonium salt and contacting the substrate with a heparin salt solution.

[0017] In addition, many attempts have been made to invent hydrophilic polymers for applications such as electrophoresis, hair treatment, and paper treatment. As revealed by Albarghouthi et al. in "Poly-N-hydroxyethylacrylamide (polyDuramide): A novel, hydrophilic, self-coating polymer matrix for DNA sequencing by capillary electrophoresis", Electrophoresis, vol. 23 (2002), p. 1429-1440, nonionic monomers such as N-hydroxyethylacrylamide have excellent hydrophilicity.

[0018] The following documents, namely WO10041527A, W010041530A, W011125713A, JP2011046619A, JP2011046652A, JP2010126482A, and JP2010090049A, teach copolymers composed of 5 to 30 mol% carboxylic acid monomers and 70 to 95 mol% alcohol-containing acrylic monomers for use in hair treatment formulations. These patent applications do not disclose the lubricity, the usefulness of the copolymers as biocompatible coatings, and their resistance to ionizing radiation. JP2006176934A teaches copolymers from methacrylamide, hydroxyethylacrylamide, and ionic vinyl monomers for use as additives to enhance the strength of paper. The latter reference does not disclose the usefulness of the copolymers as lubricious biocompatible coatings and also does not disclose resistance to ionizing radiation.

[0019] There is a need for improved lubricious biocompatible coatings that are resistant to ionizing radiation.

[0020] Typically, in medical devices or implants, a base coat exists between the substrate and the lubricious coating. The base coat can improve the stability of the lubricious coating. In the art, there is a need for an improved base coat that binds more rapidly to the lubricious top coat. A base coat that binds to a hydrophilic top coat by ultraviolet (UV) curing meets this need. SUMMARY OF THE INVENTION

[0021] The present invention relates to coating compositions for medical devices or medical implants. These novel compositions include a hydrophobic base coat polymer and a hydrophilic top coat polymer.

[0022] In some embodiments, the present invention (a) at least one photoactive monomer that is a hydrogen atom abstracting agent in an amount of 1 to 12 mol%, and (b) one or more of acrylamide, methacrylamide, acrylate, methacrylate, and N-vinylpyrrolidone in an amount of 99 to 88 mol% and relates to a coating composition having a hydrophobic polymer for use as a photoreactive base coat for medical devices or implants, the polymer having a glass transition temperature (Tg) of less than 40°C.

[0023] In certain embodiments, the base coat further has a polyfunctional aziridine. (a) 95 to 99.8 wt% of the hydrophobic polymer described herein; and (b) 0.2 to 5 wt% of the polyfunctional aziridine based on the total weight of the base coat.

[0024] The present invention also relates to a medical device or implant having a photoreactive basecoat with the coating composition described herein. In a preferred composition, the basecoat is hydrophobic. In some embodiments, the device or implant includes a hydrophilic topcoat where the basecoat is present on the substrate and the topcoat is present on the basecoat. The hydrophilic topcoat composition may or may not contain a photoactive group.

[0025] In other embodiments, the present invention relates to a coating solution having the hydrophobic basecoat coating composition described herein and a solvent.

[0026] In other embodiments, the coating solution has a polymer soluble in water or a water-alcohol solution, and the polymer is made from monomers having (a) at least one monomer that is a photo radical generator, and (b) at least one monomer having one or both of (i) an ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide; the molar ratio of (i) the ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide to the photo radical generating group is from 20:1 to 500:1.

[0027] The present invention also relates to a coated substrate having a substrate and a lubricious coating made using the coating composition described herein.

[0028] Additional embodiments relate to coating the compositions described herein in an aqueous solution.

[0029] In yet another embodiment, the present invention relates to a method of coating a substrate. In some embodiments, both a base coat and a top coat are applied to the substrate. When both the base coat and the top coat are cured with UV light, it is either (a) applying and curing the base coat before applying the top coat, or (b) applying the base coat and allowing it to dry, applying the top coat, and then curing both the base coat and the top coat with UV light.

[0030] Still other embodiments include medical devices or implants in which the lubricious coating includes a pharmaceutical or antimicrobial agent incorporated into the coating composition.

DETAILED DESCRIPTION OF THE INVENTION

[0031] The requirements for a coating intended for use in a medical device are first defined and described. Then, how the present invention meets these requirements is described in the specification.

[0032] The coatings of the present invention are suitable for use in medical devices. The coatings of the present invention have the following properties. (1) The coating must be able to form a good continuous adhesive film on the surface of the material being coated when dry. This means that the minimum film-forming temperature of the coating solution must be lower than the drying temperature anticipated during device manufacture. (2) The formed polymer film must have flexibility and adhesion such that it conforms without breaking under bending and twisting of the coated device under the expected use conditions. (3) When the coated device is immersed in an aqueous medium such as human blood for an extended period of time, the film must not become weak or lose its integrity. (4) The coating must be non-cytotoxic and present a blood-compatible surface. When in contact with human blood, the coating must not initiate blood clotting and the complement pathway. (5) The coating must be firmly and securely bonded to the substrate so that particles, fragments, or leachable components do not contaminate an aqueous medium such as human blood. (6) The coating must withstand an acceptable form of sterilization without compromising integrity, durability, and biocompatibility.

[0033] A coating that meets the above requirements is manufactured as follows.

[0034] This disclosure may be more readily understood by reference to the following description taken in conjunction with the accompanying drawings and examples, all of which form a part of this disclosure. This disclosure is not limited to the specific products, methods, conditions or parameters described and / or shown herein, and it will be understood that the terms used herein are for the purpose of exemplifying particular embodiments and are not intended to limit the disclosure of any claim. Similarly, unless otherwise specified, any description regarding possible mechanisms or mechanisms of action or reasons for improvement is intended only as an illustration, and the invention herein should not be limited by the correctness or incorrectness of the mechanisms or mechanisms of action or reasons for improvement thus suggested. Throughout this specification, it is recognized that the description refers to both a method of operating an apparatus and system and an apparatus and system that provides said method. That is, when this disclosure describes and / or claims a coating composition, medical device, coating solution or method, it is understood that these descriptions and / or claims also describe and / or claim an apparatus, device, or system for achieving these methods.

[0035] In some embodiments, the present invention (a) at least one photoactive monomer that is a hydrogen atom abstracting agent in an amount of 1 to 12 mol%, and (b) one or more of acrylamide, methacrylamide, acrylate, methacrylate, and N-vinylpyrrolidone in an amount of 99 to 88 mol% It relates to a coating composition having a polymer made from monomers having a glass transition temperature (Tg) of less than 40 °C, the polymer being a hydrophobic polymer for use as a photo-reactive base coat for medical devices or implants.

[0036] Preferred hydrophobic polymers have a glass transition temperature of less than 40 °C, 20 °C, 15 °C or 10 °C.

[0037] In a preferred embodiment of the hydrophobic polymer, the photoactive monomer which is a hydrogen atom abstracting agent is a benzophenone compound. In certain embodiments, the photoactive monomer which is a hydrogen atom abstracting agent has one or more of 4-methacryloxy 2-hydroxybenzophenone, 4-acryloxybenzophenone, 4-methacryloxybenzophenone, acrylamide benzophenone, methacrylamide benzophenone, 2-hydroxy-4-acryloxyethoxybenzophenone, and 2-hydroxy-4-methacryloxyethoxybenzophenone.

[0038] 4-Methacryloxy 2-hydroxybenzophenone (MHB) can copolymerize with (meth)acrylate monomers to produce a hydrophobic photoactive polymer. This polymer functions as a tie layer for bonding the substrate and the hydrophilic topcoat layer by UV curing. The topcoat cured in the presence of this photoactive base coat binds well even when the topcoat does not contain a photoactive component.

Chemical formula

[0039] The monomers copolymerizing with the photoactive monomer may be one or more of acrylates, methacrylates, or other monomers known to copolymerize well therewith. In certain embodiments, the polymer has a methacrylate of the following structure,

Chemical formula

[0040] In certain embodiments, the monomer that contributes a low glass temperature to the hydrophobic polymer is C 4 -C 20 acrylate having an alkyl group, such as butyl acrylate and the like.

[0041] In yet another aspect, the present invention relates to a coating solution having 2 to 15 wt% of the hydrophobic polymer coating composition described herein. In other embodiments, the solution has 3 to 13 wt% or 4 to 12 wt% or 5 to 10 wt% of the coating composition described herein. In a preferred embodiment, the solution has an organic solvent. Preferred solvents include one or more of toluene, ethanol, acetone, isopropanol, ethyl acetate, dimethylformamide, tetrahydrofuran, butanol, N-methyl-2-pyrrolidone, n-butyl acetate, 1,2-propanediol monomethyl ether acetate, isobutyl acetate, isopropyl acetate, methyl acetate, 3-methyl-1-butanol, methyl ethyl ketone, 2-methyl-1-propanol, 1-pentanol, 2-propanol, propyl acetate, dichloromethane, dimethyl sulfoxide, methyl butyl ketone, and xylene.

[0042] In certain embodiments, the base coat further has a polyfunctional aziridine. In some embodiments, the coating composition has (a) 95 to 99.8 wt% of a hydrophobic polymer; and (b) 0.2 to 5 wt% of a polyfunctional aziridine. In other embodiments, the coating composition has (a) 98 to 99.5 wt% of a hydrophobic polymer; and (b) 0.5 to 2 wt% of a polyfunctional aziridine.

[0043] In some embodiments, the present invention relates to a hydrophilic polymer coating composition for a medical device or medical implant having a polymer soluble in water or a water-alcohol solution, the polymer comprising (a) at least one monomer that is a photoinitiator, and (b) at least one monomer having one or both of (i) an ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide, and is made from monomers having a molar ratio of the one or both of (i) the ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide to the photoinitiating group of 20:1 to 500:1.

[0044] The polymer may be packaged in water or a water-alcohol mixture. The alcohol is typically a C 1 -C 6 alcohol. Preferred alcohols include methanol, ethanol and isopropanol. The ratio of water to alcohol can be from 100:0 to 50:50.

[0045] Some preferred photoinitiators for hydrophobic polymers are benzophenone compounds. In some embodiments, the photoinitiator has one or more of 4-methacryloxy 2-hydroxybenzophenone, 4-acryloxybenzophenone, 4-methacryloxybenzophenone, acrylamide benzophenone, methacrylamide benzophenone, 2-hydroxy-4-acryloxyethoxybenzophenone, 2,4-dihydroxy-4'-vinylbenzophenone, and 2-hydroxy-4-methacryloxyethoxybenzophenone. One of the preferred photoinitiating groups has 4-methacryloxy 2-hydroxybenzophenone.

[0046] 4-Methacryloxy 2-hydroxybenzophenone (MHB) can copolymerize with polar acrylates such as acrylic acid and N-(2-hydroxyethyl)acrylamide to produce hydrophilic and photoactive polymers. By UV curing, this polymer functions as a lubricious topcoat. It can also be used by adding to other hydrophilic (non-photoactive) polymers to form a lubricious coating after UV curing. [Chemical formula]

[0047] To form hydrophilic polymers, various ethylenically unsaturated monomers can be used. In some embodiments, the monomer has at least one acidic group having acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides and half thioesters of maleic acid, fumaric acid, and itaconic acid, and mixtures thereof. In one embodiment, the ethylenically unsaturated monomer has N-(2-hydroxyethyl)acrylamide and acrylic acid. In a particular embodiment, the molar ratio of N-(2-hydroxyethyl)acrylamide to acrylic acid is from 2:1 to 5:1.

[0048] Preferred acrylates and acrylamides include acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl 3-hydroxy-2-methylenebutyrate, hydroxypropyl methacrylate, 2-allyloxyethanol, 3-allyloxy-1,2-propanediol, 1,4-butanediol vinyl ether, di(ethylene glycol) vinyl ether, ethylene glycol vinyl ether, N,N-1,2-dihydroxyethylene-bis-acrylamide, N,N-1,2-dihydroxyethylene-bis-methylacrylamide, N-hydroxymethyl methacrylamide, N-tri(hydroxymethyl)-methyl-methacrylamide, or any mixture thereof.

[0049] In some embodiments, the molar ratio of (i) an ethylenic monomer having at least one acidic group and (ii) one or both of one or more acrylates or acrylamides to a photoinitiator having at least one photopolymerizable group is from 40:1 to 200:1.

[0050] In certain embodiments, the hydrophilic polymer has a weight average molecular weight (Mw) of from 20,000 to 800,000 or from 20,000 to 400,000 or 50,000 and 400,000.

[0051] Some hydrophilic polymer coating compositions further have a second polymer that is soluble in water or a water-alcohol solution. In some embodiments, the second polymer has (i) an ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide. In the second polymer, the ethylenic monomer of the second polymer has at least one acidic group and has at least one of acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides, half thioesters of maleic acid, fumaric acid, itaconic acid, and any combination thereof. Further, in the second polymer, the acrylate or acrylamide is acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl 3-hydroxy-2-methylenebutyrate, hydroxypropyl methacrylate, 2-allyloxyethanol, 3-allyloxy-1,2-propanediol, 1,4-butanediol vinyl ether, di(ethylene glycol) vinyl ether, ethylene glycol vinyl ether, N,N-1,2-dihydroxyethylene-bis-acrylamide, N,N-1,2-dihydroxyethylene-bis-methylacrylamide, N-hydroxymethyl methacrylamide, N-tri(hydroxymethyl)-methyl-methacrylamide and any mixture thereof.

[0052] In some embodiments, the second polymer has a weight average molecular weight (Mw) of 50,000 to 800,000.

[0053] The present invention also relates to a coated substrate having a substrate and a lubricious coating made using the coating composition described herein. Preferred embodiments further have a base coat that contacts both the substrate and the lubricious coating composition. A preferred base coat is hydrophobic.

[0054] The present invention also relates to a medical device or implant having a photoreactive base coat having the coating composition described herein. In some embodiments, the base coat is present between the substrate and a hydrophilic top coat. Some preferred top coats have one or more of polyacrylate, polyvinylpyrrolidone, hyaluronic acid, and polyacrylamide. In other embodiments, the top coat has an N-(2-hydroxyethyl)acrylamide and acrylic acid copolymer. Some embodiments have a plurality of covalent crosslinks between the base coat and the hydrophilic top coat.

[0055] The coating can be used on any medical device or implant suitable for the use of the coating. In some embodiments, the substrate is plastic or metal.

[0056] Preferred coated substrates have a lubricity of friction less than 25 gf as measured by a pinch test and a durability of friction less than 50 gf.

[0057] The present invention also relates to medical devices and medical implants having the coated substrates described herein. In some embodiments, the medical device or medical implant is sterilized by at least one of gamma rays, E-beams, and ethylene oxide.

[0058] In additional embodiments, the coatings described herein include a pharmaceutical or an antibacterial agent incorporated into the coating composition.

[0059] Preferred medical devices include catheters and guidewires.

[0060] In some aspects, the present invention relates to a method of coating an article. Some methods include coating a substrate with a base coat having a coating composition described herein. The base coat may be cured by exposing the base coat to UV light. In some embodiments, the base coat may be coated with a hydrophilic top coat.

[0061] In still other embodiments, the coating method includes coating a substrate with a base coat having a coating composition described herein, coating the base coat with a hydrophilic top coat, and UV curing the base coat and the top coat. The hydrophilic top coat may be photoactive (i.e., include groups that absorb UV radiation and react when exposed to UV radiation), but it is not necessary for the top coat to have photoactive groups.

[0062] The present invention relates to at least the following aspects.

[0063] Aspect 1A. A coating composition having a hydrophobic polymer for use as a photo-reactive base coat for a medical device or implant, the polymer being made from a monomer having (a) at least one photoactive monomer that is a hydrogen atom abstracting agent in an amount of 1 to 12 mol% and (b) one or more of acrylamide, methacrylamide, acrylate, methacrylate, and N-vinylpyrrolidone in an amount of 99 to 88 mol%, the polymer having a glass transition temperature (Tg) of less than 40°C.

[0064] Aspect 1B. (a) At least one photoactive monomer that is a hydrogen atom abstracting agent in an amount of 1 to 5 mol%, and (b) one or more of acrylamide, methacrylamide, acrylate, methacrylate, and N-vinylpyrrolidone in an amount of 99 to 95 mol%, and having a polymer made from the monomers, the polymer having a glass transition temperature (Tg) of less than 40°C, a coating composition having a hydrophobic polymer for use as a photo-reactive base coat for medical devices or implants.

[0065] Aspect 2. A coating composition according to Aspect 1A - 1B, further comprising a polyfunctional aziridine.

[0066] Aspect 3. A coating composition according to Aspect 2, comprising (a) 95 to 99.8 wt% of the hydrophobic polymer; and (b) 0.2 to 5 wt% of the polyfunctional aziridine.

[0067] Aspect 4. A coating composition according to any one of Aspect 1A - 3, having the following structure

Chemical formula

[0068] Aspect 5. In the coating composition according to Aspect 4, R is one or more of methyl, ethylhexyl, isodecyl, dodecyl.

[0069] Aspect 6. In the coating composition according to Aspect 4, the hydrophobic polymer has hydroxyethyl methacrylate and N-vinylpyrrolidone.

[0070] Aspect 7. In the coating composition according to any one of Aspect 1A - 6, the hydrophobic polymer is C 4 -C 20A coating composition having an acrylate having an alkyl group.

[0071] Aspect 8. In the coating composition of any one of Aspects 1A to 7, the photoactive monomer which is the hydrogen atom abstracting agent has a benzophenone moiety, a coating composition.

[0072] Aspect 9. In the coating composition according to Aspect 8, the photoactive monomer which is the hydrogen atom abstracting agent has one or more of 4-methacryloxy 2-hydroxybenzophenone, 4-acryloxybenzophenone, 4-methacryloxybenzophenone, acrylamidebenzophenone, methacrylamidebenzophenone, 2-hydroxy-4-acryloxyethoxybenzophenone and 2-hydroxy-4-methacryloxyethoxybenzophenone, a coating composition.

[0073] Aspect 10. A coating composition according to any one of Aspects 1A to 9, having a Tg of less than 20°C, a coating composition.

[0074] Aspect 11. A medical device or implant having a photoreactive base coat having a coating composition according to any one of Aspects 1A to 10.

[0075] Aspect 12. In the medical device of Aspect 11, the base coat is present between a substrate and a hydrophilic top coat, a medical device.

[0076] Aspect 13. In the medical device of Aspect 12, the top coat has one or more of polyacrylate, polyvinylpyrrolidone, hyaluronic acid, and polyacrylamide, a medical device.

[0077] Aspect 14. In the medical device of Aspect 12, the top coat has a copolymer of N-(2-hydroxyethyl)acrylamide and acrylic acid, a medical device.

[0078] Aspect 15. A medical device according to Aspect 11, wherein the medical device is a catheter or a guide wire.

[0079] Aspect 16. A medical device according to Aspect 12, having a plurality of covalent crosslinks between the base coat and the hydrophilic top coat.

[0080] Aspect 17. A coating solution having a coating composition according to any one of Aspects 1 to 10 in an amount of 2 to 15 wt% in a solvent.

[0081] Aspect 18. The coating solution according to Aspect 17, wherein the solvent is an organic solvent.

[0082] Aspect 19. The coating solution according to Aspect 18, wherein the solvent has one or more of toluene, ethanol, acetone, isopropanol, ethyl acetate, dimethylformamide, tetrahydrofuran, butanol, N-methyl-2-pyrrolidone, n-butyl acetate, 1,2-propanediol monomethyl ether acetate, isobutyl acetate, isopropyl acetate, methyl acetate, 3-methyl-1-butanol, methyl ethyl ketone, 2-methyl-1-propanol, 1-pentanol, 2-propanol, propyl acetate, dichloromethane, dimethyl sulfoxide, methyl butyl ketone, and xylene.

[0083] Aspect 20. A method for forming a coated article, comprising the step of coating a substrate with a base coat having a coating composition according to any one of Aspects 1A to 10.

[0084] Aspect 21. The method according to Aspect 20, further comprising the step of curing the base coat by exposing the base coat to UV light.

[0085] Aspect 22. The method according to Aspect 21, further comprising the step of coating the base coat with a hydrophilic top coat.

[0086] Aspect 23. The method of Aspect 20, further comprising: (a) a step of coating the base coat with a hydrophilic top coat; and (b) a step of curing the base coat and the top coat with UV light.

[0087] Aspect 24. A coating composition for a medical device or medical implant having a polymer soluble in water or a water-alcohol solution, wherein the polymer is made from monomers comprising: (a) at least one monomer that is a photoinitiator having one or more of 4-methacryloxy 2-hydroxybenzophenone, 4-acryloxybenzophenone, 4-methacryloxybenzophenone, acrylamide benzophenone, methacrylamide benzophenone, 2-hydroxy-4-acryloxyethoxybenzophenone, 2,4-dihydroxy-4'-vinylbenzophenone, and 2-hydroxy-4-methacryloxyethoxybenzophenone; and (b) monomers comprising (i) at least one ethylenically unsaturated monomer having at least one acidic group and (ii) at least one monomer having one or both of acrylate or acrylamide. The at least one ethylenically unsaturated monomer having at least one acidic group includes acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides and half thioesters of maleic acid, fumaric acid and itaconic acid, and mixtures thereof. The acrylate or acrylamide includes acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl 3-hydroxy-2-methylenebutyrate, hydroxypropyl methacrylate, 2-allyloxyethanol, 3-allyloxy-1,2-propanediol, 1,4-butanediol vinyl ether, di(ethylene glycol) vinyl ether, ethylene glycol vinyl ether, N,N-1,2-dihydroxyethylene-bis-acrylamide, N,N-1,Those having 2-hydroxyethylene-bis-methylacrylamide, N-hydroxymethylmethacrylamide, N-tri(hydroxymethyl)-methyl-methacrylamide or any mixture thereof, wherein the molar ratio of (i) an ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide to the photo radical generating group is from 20:1 to 500:1, a coating composition.

[0088] Aspect 25. The coating composition according to aspect 24, wherein the photo radical generating group has 4-methacryloxy-2-hydroxybenzophenone.

[0089] Aspect 26. The coating composition according to aspect 24, wherein the ethylenic monomer has N-(2-hydroxyethyl)acrylamide and acrylic acid.

[0090] Aspect 27. The coating composition according to aspect 26, wherein the molar ratio of the N-(2-hydroxyethyl)acrylamide and the acrylic acid is from 2:1 to 5:1.

[0091] Aspect 28. The coating composition according to aspect 24, wherein the molar ratio of (i) an ethylenic monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide, to a photo radical generator having at least one photopolymerizable group is from 40:1 to 200:1.

[0092] Aspect 29. The coating composition according to aspect 24, wherein the polymer has a weight average molecular weight (Mw) of 20,000 to 800,000.

[0093] Aspect 30. The coating composition according to aspect 24, further having a second polymer soluble in water or a water-alcohol solution.

[0094] Aspect 31. A coating composition according to Aspect 30, having one or both of (i) an ethylenically unsaturated monomer having at least one acidic group and (ii) one or more of acrylate or acrylamide.

[0095] Aspect 32. The coating composition according to Aspect 31, wherein the ethylenically unsaturated monomer of the second polymer has at least one acidic group, and the ethylenically unsaturated monomer of the second polymer having at least one acidic group has one or more of acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides and half thioesters of maleic acid, fumaric acid, itaconic acid, and any combination thereof.

[0096] Aspect 33. The coating composition according to Aspect 31, wherein the acrylate or acrylamide of the second polymer is acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl 3-hydroxy-2-methylenebutyrate, hydroxypropyl methacrylate, 2-allyloxyethanol, 3-allyloxy-1,2-propanediol, 1,4-butanediol vinyl ether, di(ethylene glycol) vinyl ether, ethylene glycol vinyl ether, N,N-1,2-dihydroxyethylene-bis-acrylamide, N,N-1,2-dihydroxyethylene-bis-methylacrylamide, N-hydroxymethyl methacrylamide, N-tri(hydroxymethyl)-methyl-methacrylamide and any mixture thereof.

[0097] Aspect 34. A coating composition according to Aspect 31, wherein the second polymer has a weight average molecular weight (Mw) of 50,000 to 800,000.

[0098] Aspect 35. A coating composition according to Aspect 24, further comprising water or a water / alcohol mixture.

[0099] Aspect 36. A coated substrate having a substrate and a lubricating coating made using a coating composition according to any one of Aspects 24 to 35.

[0100] Aspect 37. A coated substrate according to Aspect 36, further comprising a base coat that contacts both the substrate and the lubricating coating composition.

[0101] Aspect 38. A coated substrate according to Aspect 37, wherein the base coat is hydrophobic.

[0102] Aspect 39. A coated substrate according to Aspect 36, wherein the substrate is plastic.

[0103] Aspect 40. A coated substrate according to Aspect 36, wherein the substrate is metal.

[0104] Aspect 41. A coated substrate according to any one of Aspects 36 to 40, wherein the coated substrate has lubricity of friction measured by a pinch test of less than 25 gf and durability of friction of less than 50 gf.

[0105] Aspect 42. A medical device or medical implant having a coated substrate according to any one of Aspects 36 to 41.

[0106] Aspect 43. A medical device or medical implant according to Aspect 42, wherein the medical device or medical implant is sterilized by at least one of gamma rays, E-beams, and ethylene oxide.

[0107] Aspect 44. A medical device or medical implant according to Aspect 42 or 43, wherein the lubricious coating comprises a pharmaceutical or antibacterial agent incorporated into the coating composition.

[0108] Examples The present invention is illustrated by the following non-limiting examples.

[0109] The following abbreviations are used in this document: MHB - 4-methacryloxy-2-hydroxybenzophenone was a monomer that imparted photoactivity to the copolymer. Purchased from Polysciences and Bimax. The purity was confirmed by nuclear magnetic resonance (NMR) performed using a Bruker 400 MHz NMR from UScience. BA - Butyl acrylate MMA - Methyl methacrylate HEMA - Hydroxyethyl methacrylate NVP - N-Vinylpyrrolidone EHMA - Ethylhexyl methacrylate iDMA - Isodecyl methacrylate DDMA - Dodecyl methacrylate AA - Acrylic acid HEAA - N-(2-Hydroxyethyl)acrylamide PVP - Polyvinylpyrrolidone HAP - Hydrophilic acrylic copolymer, a copolymer of AA and HEAA

[0110] The coating was applied to various substrates in the form of rods and tubes. The rods were made of stainless steel or PMMA and had a diameter of 0.125 inches. The Pebax (trademark) 35D and 55D plastic tubes had an outer diameter of 0.079 inches and a wall thickness of 0.005 inches. The tubes were placed on stainless steel rods to ensure stability before coating. The coating process involved wiping the rods with isopropyl alcohol, dip-coating them in the base coat solution at 0.2 in / second, drying them at 60 °C for 10 minutes, dip-coating them in the top coat solution at 0.2 in / second, and drying them at 60 °C for 10 minutes. After all the coatings were completed, the rods were exposed to UV irradiation.

[0111] UV curing was performed using a Uvitron IntelliRay model UV0832 UV Cure unit equipped with a UVA 600-watt metal halide lamp. The irradiance was measured using an EIT Uvicure Plus II radiometer purchased from INPRO Technologies. This one-channel UVA radiometer measures radiation from 320 to 390 nanometers (nm).

[0112] Two different methods were used to irradiate the rods with uniform radiation. In the first method, a hexagonal coupler was attached to the rod to provide a fixed shape for rotating the coated rod while curing. Next, the sample was rotated 6 times, allowing all surfaces to be exposed. The rotation pattern was 0°, 120°, 240°, 60°, 180°, 300°. The second method involved continuously rotating the rod by a motor at 20 rpm during UV curing.

[0113] Typical irradiation times in the examples are 2 to 30 minutes, and typical irradiation doses are 100 to 200 mW / cm2 (for 320 to 390 nm from a UVA metal halide lamp). It should be noted that not all of the irradiation from 320 to 390 nm is useful for photocrosslinking, and only the wavelengths actually absorbed by the photoactive groups can lead to the reaction. Also, it is understood that lower irradiances than those used in these examples can be compensated for by an increase in the irradiation time.

[0114] The friction of the coating was tested with a Chatillon CS225 Force Measurement Machine. It was equipped with a heated water bath and pinch pads that pressed against each other with a constant force. The water bath was filled with PBS solution and heated to 37°C. The pinch pads were submerged in water and pressed against each other with a force of 470 grams (g). Friction is measured as the grams of force required to push or pull the sample through the pad. Lubricity and durability are determined by averaging the grams of force when the sample is pulled through the pad. Lubricity is the average value for 1 to 3 cycles, and durability is the force for 30 cycles.

[0115] 4-methacryloxy 2-hydroxybenzophenone was copolymerized with a low glass transition temperature (meth)acrylate monomer to prepare a photoactive base coat. The synthesized photoactive base coat polymers are summarized in Table 1.

Table 1

[0116] Poly(methyl methacrylate) (PMMA) rods were coated with the base coat polymer BP-5 and a polyvinylpyrrolidone (PVP) top coat (Aldrich 1,300,000 molecular weight by light scattering method). The coated rods had 186 milliwatts (mW / cm per square centimeter 2) irradiance, and cured through each of the six rotations. After the pinch test, the rod was rinsed with cold tap water for 10 seconds, immersed in a 0.5% aqueous congo red solution, and rinsed again for 10 seconds. The presence of the bound PVP, indicated by a deep red color, indicates that grafting occurred between the photoactive base coat and the PVP top coat.

[0117] A PVP top coat with four different UV-curable base coat polymers was tested on PMMA substrate rods. UV curing was carried out at an irradiance of 166 mW / cm 2 dose, over 20 minutes for each of the six rotations. The samples showed considerable lubricity but only lasted for 10 - 20 cycles. The results are summarized in Table 2.

Table 2

Table 3

[0118] The results summarized in the above examples indicate that good lubricity and durability can be obtained with a photoactive base coat even without photoactivity in the top coat. The drawback of the UV curing process used in these examples is that it is necessary to stop the UV curing during curing and rotate the sample manually five times. To solve this, a motor was installed to continuously rotate the sample at 20 rpm during curing. It is expected that this will result in more uniform UV curing around the rod or tube. This method is not only highly convenient but also, as shown below, provides even better lubricity and durability with a shorter curing time.

[0119] Table 4 shows a comparison of several compositions using different monomer compositions and different amounts of photoactive monomers. The results indicate that lubricious and durable coatings can be provided using various low glass temperature monomers. In these examples, the topcoat does not contain a photoactive component.

Table 4

[0120] Incorporating a trifunctional aziridine such as trimethylolpropane tris(2-methyl-1-aziridinepropionate) (crosslinking agent CX-100) into the basecoat enables the obtaining of a coated rod with even better durability. Polyfunctional aziridines are known as crosslinking agents in the thermosetting process. The results in Table 5 indicate an improvement in durability.

Table 5

[0121] The foregoing examples have demonstrated that the combination of the photoactive base coat of the present invention and the hydrophilic top coat having no photoactivity brings about good lubricity and durability. The following examples show that even better performance can be obtained when photoactivity is incorporated into the top coat.

[0122] Poly(HEAA-co-AA) in Table 6. 29.79 g of N-(2-hydroxyethyl)acrylamide (HEAA) and 6.21 g of acrylic acid (AA) were reacted in 263 mL of water to prepare a polymer. The polymerization initiators were ammonium persulfate and sodium hydroxymethanesulfinate hydrate. 0.015 mL of 1% FeSO 4 solution was added to catalyze the reaction. The polymerization was carried out at 40 °C under N 2 atmosphere. The polymer was purified by dialysis or precipitation with acetone (similar to Example 1 of US2013 / 0323291 A1).

[0123] Poly(HEAA-co-AA-co-MHB) 1-4 in Table 6. 15.29 g of HEAA, 3.19 g of AA, 1.00 g, 0.50 g, or 0.25 g of MHB were reacted with 40 mL of IPA and 30 mL of water to prepare a photoactive polymer. 0.59 mL of a 50 mg / mL solution of azobisisobutyronitrile (AIBN) in THF was added to the monomer solution. After sparging this solution for 30 minutes to remove oxygen, it was heated at 60 °C for 24 hours. After the reaction was completed, the polymer was precipitated with 150 mL of ethyl acetate. The solvent was decanted off, and the polymer was dried in an oven at 60 °C, and the remaining solvent was removed under vacuum. The polymer was dissolved in a 50:50 mixture of IPA and water.

[0124] Polymers (HEAA-co-AA-co-MHB) 5 - 7 in Table 6. 15.29 g of HEAA, 3.19 g of AA, and 1.00 g, 0.50 g, or 0.25 g of MHB were reacted with 40 mL of ethanol and 30 mL of water to prepare a photoactive polymer. 0.245 mL of a 20 mg / mL solution of (AIBN) in THF was added to the monomer solution. The solution was sparged for 30 minutes to remove oxygen and then heated at 60 °C for 24 hours. After the reaction was complete, the polymer was precipitated with 150 mL of ethyl acetate. The solvent was decanted off, and the polymer was dried in an oven at 60 °C to remove the remaining solvent under vacuum. The polymer was dissolved in a 50:50 mixture of ethanol and water.

[0125] The molecular weights of these hydrophilic photoactive polymers were determined by SEC using a Waters 1515 isocratic high-performance liquid chromatography HPLC pump, a Waters 2489 UV / visible detector set at 276 nm and 290 nm, a Waters 2414 refractive index detector, and three columns (two Waters Ultrahydrogel 2000 and one Waters Ultrahydrogel 250). The molecular weights were calculated using Empower3 software by comparison with poly(acrylic acid) standards. [Table 6]

[0126] The coating was applied to Pebax (trademark) 55D plastic tubes by the dip coating method. The outer diameter of the Pebax (trademark) tube was 0.201 cm (0.079 inches), and the wall thickness was 0.0127 cm (0.005 inches). The tube was placed on a stainless-steel rod to ensure stability. First, the tube was dipped into the base coat, extracted at a speed of 0.508 cm (0.2 inches) per second, rotated in the UV chamber for 5 minutes, and set to the desired intensity. Next, the tube was dipped into the top coat, extracted at 0.508 cm (0.2 inches) per second, and rotated in the UV chamber for 5 minutes to set to the desired intensity.

[0127] UV curing was carried out using a Uvitron IntelliRay model UV0832 UV Cure unit equipped with a 600-watt UVA metal halide lamp. The irradiance was measured using an EIT Uvicure Plus II radiometer purchased from INPRO Technologies. This one-channel UVA radiometer measures radiation from 320 to 390 nm.

[0128] The friction of the coating was measured by performing a pinch test using a Tinius Olsen 5ST Electromechanical Testing Machine equipped with a 10 N load cell, and data was collected using Horizon software. The Tinius Olsen is equipped with a heated water bath and pinch pads that press against each other with a constant force. The water bath is filled with PBS solution and heated to 37 °C. The pinch pads are submerged in water and pressed against each other with a force of 450 g. Friction is measured in grams of force required to push or pull the sample through the pad. Lubricity and durability are determined by the average value in grams of force when the sample is pulled through the pad. Lubricity is the average value for 2 - 4 cycles, and durability is the average value for 28 - 30 cycles.

[0129] The base coat solution was made using the two aforementioned photoactive base coat polymers. The base coat polymers can be diluted with various solvents including isopropanol (IPA) and ethanol. Base coat A: A 10 wt% solution of a copolymer of 2-ethylhexyl methacrylate (EHMA), N-vinylpyrrolidone (NVP), (hydroxyethyl) methacrylate (HEMA), and MHB in propylene glycol methyl ether acetate, PMA, with a polyaziridine crosslinking agent added. Base coat B: A 10 wt% solution of a copolymer of butyl acrylate (BA), methyl methacrylate (MMA), NVP, HEMA, and MHB in PMA, with a polyaziridine crosslinking agent added.

[0130] The Pebax® 55D tube was coated with base coat A and, after 5 minutes of UV curing, this was coated in water with a top coat containing the photoactive polymer described in Table 6 together with 2% poly(HEAA-co-AA) and a surfactant. Table 7 shows the results of friction tests when different top coats were cured at different UV light intensities.

Table 7

[0131] Table 8 shows the results of friction tests for different top coats using base coat B. The photoactive top coats were poly(HEAA-co-AA-co-MHB), poly(HEAA-co-AA), and those containing a surfactant in water as described in Table 1.

Table 8

[0132] The examples in Table 9 show that the photoactive base coat functions well when applied directly to the substrate. That is, a hydrophobic base coat is not necessary for good lubricity and durability with a photoactive hydrophilic top coat. The photoactive top coat was applied twice and cured for 5 minutes after each application. As above, the top coat solution had one of the photoactive top coats from Table 6, poly(HEAA-co-AA), and a surfactant in water.

Table 9

[0133] In this specification, unless otherwise specified, words having the ordinary meaning as understood by those skilled in the relevant technical field are used. However, to avoid misunderstanding, the meaning of specific terms is specifically defined or clarified.

[0134] In this disclosure, the singular forms "a", "an", and "the" include plural references, and a reference to a particular numerical value includes at least that particular numerical value unless the context clearly indicates otherwise. Thus, for example, a reference to "a material" is a reference to at least one such material and its equivalents known to those skilled in the art.

[0135] It will be understood that the terms used herein are for the purpose of describing particular embodiments only and are not intended to be limiting. As used in this specification and the appended claims, the term "comprising" can include embodiments "consisting of" and "consisting essentially of". Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. A number of terms defined herein will be referred to in this specification and the appended claims that follow.

[0136] When values are represented as approximations by use of the descriptor "about", it will be understood that a particular value forms another embodiment. In general, the use of the term "about" may vary depending on the desired characteristics to be obtained by the disclosed subject matter and, based on its function, indicates an approximation to be interpreted in the particular context in which it is used. One of ordinary skill in the art will be able to interpret this routinely. In some cases, the number of significant figures used for a particular value may be one non-limiting way of determining the scope of the word "about". In other cases, the gradation used for a series of values can be used to determine the intended scope within which the term "about" can be used for each value.

[0137] In this case, all ranges are inclusive and combinable. That is, the values recited within a range include all values within that range, including the endpoint values.

[0138] When a list is presented, unless otherwise specified, each individual element of that list and all combinations of that list are to be understood as being interpreted as separate embodiments. For example, a list of embodiments presented as "A, B, or C" is to be interpreted as including the embodiments "A", "B", "C", "A and B", "A and C", "B and C", or "A, B, and C".

[0139] For the sake of clarity, it should be understood that certain features of the present invention described in the context of separate embodiments may also be provided in combination in a single embodiment. That is, unless clearly incompatible or explicitly excluded, individual embodiments are considered combinable with other possible embodiments, and such combinations are considered to be another embodiment. Conversely, for the sake of brevity, the various features of the present invention described in the context of a single embodiment may also be provided separately or in any partial combination. Furthermore, embodiments may be described as part of a series of steps or part of a more general structure, but each such step or part may also be considered an independent embodiment in itself.

[0140] As used herein, the terms "article" and "substrate" may be a layer, plurality of layers, or block of material having at least one surface modified by the coating composition described herein, and are not limited to any particular shape or size.

[0141] The glass transition temperature (Tg) is determined using Fox's equation and the literature values of the homopolymers. Fox's equation is as follows. TIFF2025087670000014.tif16153 Here, T g,mix and T g,i are the glass transition temperatures of the mixture / copolymer and the component in Kelvin units, respectively, and ω i is the mass fraction of component i. A low T g The monomer that forms the homopolymer has a low T gis required to produce a copolymer having '. Examples include butyl acrylate (Tg = -54 °C), 2-ethylhexyl methacrylate (-10), isodecyl methacrylate (-30), and dodecyl methacrylate (-65). The homopolymer Tg of some other monomers used are 100 °C for MMA, 20 °C for BMA, 120 °C for NVP, 105 °C for HEMA, 143 °C for MHB, and 105 °C for acrylic acid.

[0142] In the case of the two components A and B, the Fox equation decreases as follows. TIFF2025087670000015.tif18151

[0143] As used herein, the term "hydrophobic" refers to a polymer that does not dissolve in an aqueous solution. The crosslinked hydrophobic polymer does not swell significantly in water (< 50%).

[0144] The term "hydrophilic" refers to a polymer that is soluble in water or a water-alcohol solution. The crosslinked hydrophilic polymer swells significantly in an aqueous solution (> 100%). A "hydrophilic" substrate surface is made of a polymer in which the uncured or non-crosslinked polymer is soluble in water or a water-alcohol solution where the water is more than 50%.

[0145] Unless otherwise specified, all molecular weights are weight-average molecular weights (Mw).

Claims

1. 1. A coating composition for a medical device or medical implant having a polymer soluble in water or a water-alcohol solution, said polymer comprising: (a) at least one monomer that is a photoradical generator having one or more of 4-methacryloxy 2-hydroxybenzophenone, 4-acryloxybenzophenone, 4-methacryloxybenzophenone, acrylamide benzophenone, methacrylamide benzophenone, 2-hydroxy-4-acryloxyethoxybenzophenone, 2,4-dihydroxy-4′-vinyl benzophenone, and 2-hydroxy-4-methacryloxyethoxybenzophenone; and (b) (i) an ethylenic monomer having at least one acidic group, and (ii) at least one monomer having one or both of an acrylate or an acrylamide. and made from a monomer having the formula: The ethylenic monomer having at least one acidic group comprises acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides and half thioesters, fumaric acid and itaconic acid, and mixtures thereof; The acrylate or acrylamide comprises acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl 3-hydroxy-2-methylenebutyrate, hydroxypropyl methacrylate, 2-allyloxyethanol, 3-allyloxy-1,2-propanediol, 1,4-butanediol vinyl ether, di(ethylene glycol)vinyl ether, ethylene glycol vinyl ether, N,N-1,2-dihydroxyethylene-bis-acrylamide, N,N-1,2-dihydroxyethylene-bis-methylacrylamide, N-hydroxymethyl methacrylamide, N-tri(hydroxymethyl)-methyl-methacrylamide, or any mixture thereof; the molar ratio of one or both of (i) the ethylenic monomer having at least one acidic group, and (ii) the one or more of the acrylates or acrylamides to the photoradical generating group is from 20:1 to 500:1; Coating composition.

2. 2. The coating composition of claim 1, wherein the photoradical generating group comprises 4-methacryloxy-2-hydroxybenzophenone.

3. The coating composition of claim 1, wherein the ethylenic monomer comprises N-(2-hydroxyethyl)acrylamide and acrylic acid.

4. The coating composition of claim 3, wherein the molar ratio of said N-(2-hydroxyethyl)acrylamide and said acrylic acid is from 2:1 to 5:

1.

5. 2. The coating composition according to claim 1, wherein the molar ratio of one or both of (i) the ethylenic monomer having at least one acidic group and (ii) the one or more of acrylates or acrylamides to the photoradical generator having at least one photopolymerizable group is from 40:1 to 200:

1.

6. The coating composition of claim 1, wherein the polymer has a weight average molecular weight (Mw) of 20,000 to 800,000.

7. 10. The coating composition of claim 1 further comprising a second polymer that is soluble in water or a water-alcohol solution.

8. 8. The coating composition of claim 7, comprising one or both of: (i) an ethylenic monomer having at least one acidic group; and (ii) one or more of an acrylate or an acrylamide.

9. 9. The coating composition of claim 8, wherein the ethylenic monomer of the second polymer having at least one acidic group comprises one or more of acrylic acid, methacrylic acid, 2-ethylacrylic acid, 2-propylacrylic acid, acryloxypropionic acid, isocrotonic acid, maleic anhydride, maleic acid and half esters, half amides and half thioesters, fumaric acid, itaconic acid, and any combination thereof.

10. 9. The coating composition of claim 8, wherein the acrylate or acrylamide of the second polymer is selected from the group consisting of acrylamide, N-(2-hydroxyethyl)acrylamide, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, and N-(2-hydroxyethyl)methacrylamide, N-acryloylamide-ethoxyethanol, N-(hydroxymethyl)acrylamide, N-[tris(hydroxymethyl)methyl]acrylamide, 4-hydroxybutyl acrylate, hydroxypropyl acrylate, methyl and mixtures of any of these.

11. The coating composition of claim 8, wherein the second polymer has a weight average molecular weight (Mw) of 50,000 to 800,000.

12. The coating composition of claim 1 further comprising water or a water / alcohol mixture.

13. A substrate; A lubricious coating prepared using the coating composition of claim 1. having Coated substrate.

14. 14. The coated substrate of claim 13 further comprising a basecoat in contact with both the substrate and the lubricious coating composition.

15. 15. The coated substrate of claim 14, wherein the base coat is hydrophobic.

16. 14. The coated substrate of claim 13, wherein the substrate is plastic.

17. The coated substrate of claim 13, wherein the substrate is a metal.

18. 14. The coated substrate of claim 13, wherein the coated substrate has a lubricity of less than 25 gf of friction and a durability of less than 50 gf of friction as measured by a pinch test.

19. A medical device or medical implant comprising the coated substrate of claim 13.

20. 20. The medical device or medical implant of claim 19, wherein the medical device or medical implant is sterilized by at least one of gamma radiation, E-beam, and ethylene oxide.

21. 20. The medical device or medical implant of claim 19, wherein the lubricious coating comprises a pharmaceutical or antimicrobial agent incorporated into the coating composition.

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