the medical device is coated with a thin coherent bond coat of acrylics , epoxies , acetals , ethylene copolymers , vinyl polymers containing hydroxyl , amine , carboxyl , amide or other reactive groups , and copolymers thereof . outer layers may be applied and remain adherent to the substrate in water for an extended period . the bond coat may comprise cross linkers such as urea resins , melamines , isocyanates , and phenolics . preferred polymers include vinylpyrrolidone - vinyl acetate , styrene acrylic polymer , ethylene acrylic acid copolymer , carboxyl function acrylic polymer , hydroxyl function acrylic polymer , and acrylic dispersion polymer . the coatings may be applied to inert metal or plastic surfaces of medical devices such as needles , guide wires , catheters , surgical instruments , equipment for endoscopy , wires , stents , angioplasty balloons , wound drains , arteriovenous shunts , gastroenteric tubes , urethral inserts , laparoscopic equipment , pellets , and implants . methods of coating and coating liquids are provided .