Patent ID: 6201042
Filing Date: 2001-03-13
Classification: C09J

Abstract:
In a method of making a repositionable pressure-sensitive adhesive of tacky elastomeric microspheres of an average particle diameter of 20 to 60 microns wherein the microspheres are polymerized and form an aqueous suspension partly of solids which includes a surfactant of ethoxylated oleyl alcohol, the improvement which comprisesa) adding to the suspension wash water to which some of the surfactant transfers,b) removing the wash water along with the transferred surfactant to leave a suspension of a greater amount of solids and a lesser amount of said surfactant,c) repeating the addition and removal of the wash water until a predetermined reduced amount of surfactant remains in the suspension, andd) thereafter adding a thickening agent to said aqueous suspension,e) said predetermined reduced amount of said surfactant in the aqueous suspension is 0.028 percent to 0.133 percent by weight on a mass basis of both solids and liquid before addition of the thickening agent and 0.020 percent to 0.093 percent by weight on a mass basis of both solids and liquid after addition of the thickening agent,f) whereby migration of said surfactant from the adhesive is at least substantially reduced.