Patterned silicone coating

Abstract

A method of applying a patterned coating of a silicone adhesive to a substrate sheet, comprising the steps of pattern coating a silicone precursor composition onto the substrate, followed by thermally curing the precursor composition coated on the substrate. The precursor composition is a viscous fluid, and the pattern coating is performed by suitably modified block printing, intaglio printing or screen printing methods. Also provided are coated substrates obtainable by the methods of the invention, and wound dressings comprising such coated substrates.

What is claimed is: 
     
         1 . A wound dressing, comprising:
 a backing sheet comprising a semipermeable polyurethane film;   a pattern of silicone adhesive printed on a first surface of the backing sheet; and   an absorbent island adhered to the backing sheet by the pattern of silicone adhesive.   
     
     
         2 . The wound dressing of  claim 1 , wherein the absorbent island comprises a polyurethane foam. 
     
     
         3 . The wound dressing of  claim 1 , wherein the pattern of silicone adhesive comprises an open network of adhesive. 
     
     
         4 . The wound dressing of  claim 3 , wherein the open network of adhesive defines a plurality of regions of adhesive that are separated from one another by portions of the backing sheet along which no silicone adhesive is provided. 
     
     
         5 . The wound dressing of  claim 1 , wherein the pattern of silicone adhesive is printed directly on the first surface of the backing sheet such that the silicone adhesive directly contacts the polyurethane film. 
     
     
         6 . A wound dressing, comprising:
 a backing sheet comprising a film;   an absorbent island adhered to the lower surface of the backing sheet; and   a plurality of silicone adhesive structures printed on a lower surface of the backing sheet;   wherein each adhesive structure is separated from an adjacent silicone adhesive structure by a portion of the lower surface of the backing sheet along which no silicone adhesive is provided.   
     
     
         7 . The wound dressing of  claim 6 , wherein the silicone adhesive structures are bonded directly to the backing sheet. 
     
     
         8 . The wound dressing of  claim 6 , wherein the backing sheet comprises a hydrophilic material. 
     
     
         9 . The wound dressing of  claim 6 , wherein each silicone adhesive structure has a diameter of at least 2 mm. 
     
     
         10 . The wound dressing of  claim 6 , wherein the silicone adhesive structures are printed on the lower surface of the backing sheet such that a density of silicone adhesive along the lower surface of the backing sheet is from approximately 20 grams to approximately 350 grams of silicone adhesive per square meter. 
     
     
         11 . The wound dressing of  claim 6 , wherein the backing sheet has a surface area from approximately 1 cm2 to approximately 1000 cm2. 
     
     
         12 . The wound dressing of  claim 6 , wherein the entirety of an outer periphery of each adhesive structure is surrounded by portions of the lower surface of the backing sheet along which no silicone adhesive is provided. 
     
     
         13 . A wound dressing, comprising:
 a backing sheet having a first surface configured to be attached to a patient;   an absorbent layer; and   a pattern of silicone adhesive printed on the first surface of the backing sheet;   wherein the pattern of silicone adhesive is bonded to and directly contacts the first surface of the backing sheet.   
     
     
         14 . The wound dressing of  claim 13 , wherein the first surface of the backing sheet to which the pattern of silicone adhesive is bonded comprises a hydrophilic material. 
     
     
         15 . The wound dressing of  claim 13 , wherein the first surface of the backing sheet comprises a center portion that is free of adhesive. 
     
     
         16 . The wound dressing of  claim 15 , wherein the pattern of silicone adhesive defines a margin that extends between an outer periphery of the center portion and an outer perimeter of the backing sheet. 
     
     
         17 . The wound dressing of  claim 16 , wherein the margin extends about the entirety of the outer periphery of the center portion. 
     
     
         18 . The wound dressing of  claim 16 , wherein the margin has a width from approximately 1 cm to approximately 4 cm. 
     
     
         19 . The wound dressing of  claim 14 , wherein the hydrophilic material comprises a polyurethane or a hydrocolloid. 
     
     
         20 . The wound dressing of claim of  claim 13 , wherein prior to the wound dressing being attached to a patient, a cover sheet including a plurality of raised, folded tabs is adhered to the first surface of the backing layer by the silicone adhesive.